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Glossary of VSA attributes

This Glossary alphabetically lists all attributes used in the VSAv20110218 database(s) held in the VSA. If you would like to have more information about the schema tables please use the VSAv20110218 Schema Browser (other Browser versions).
A B C D E F G H I J K L M
N O P Q R S T U V W X Y Z

Y

NameSchema TableDatabaseDescriptionTypeLengthUnitDefault ValueUnified Content Descriptor
y combo17CDFSSource COMBO17 y-coordinate on image cdfs_r.fit real 4 pix    
y svNgc253Detection VSASVNGC253 Y coordinate of detection {catalogue TType keyword: Y_coordinate}
Intensity-weighted isophotal centre-of-gravity in Y.		 real 4 pixels   POS_PLATE_Y
y svOrionDetection VSASVORION Y coordinate of detection {catalogue TType keyword: Y_coordinate}
Intensity-weighted isophotal centre-of-gravity in Y.		 real 4 pixels   POS_PLATE_Y
y ultravistaDetection VSAUltraVISTA Y coordinate of detection (SE: Y_IMAGE) {catalogue TType keyword: Y_coordinate}
Intensity-weighted isophotal centre-of-gravity in Y.		 real 4 pixels   POS_PLATE_Y
y ultravistaDetection, videoDetection VSAQC Y coordinate of detection (SE: Y_IMAGE) {catalogue TType keyword: Y_coordinate}
Intensity-weighted isophotal centre-of-gravity in Y.		 real 4 pixels   POS_PLATE_Y
y ultravistaListRemeasurement VSAUltraVISTA Y coordinate of detection {catalogue TType keyword: Y_coordinate}
Intensity-weighted isophotal centre-of-gravity in Y.		 real 4 pixels   POS_PLATE_Y
y ultravistaListRemeasurement, vhsDetection, vhsListRemeasurement, videoListRemeasurement, vikingDetection, vikingListRemeasurement, vmcDetection, vmcListRemeasurement, vvvDetection, vvvListRemeasurement VSAQC Y coordinate of detection {catalogue TType keyword: Y_coordinate}
Intensity-weighted isophotal centre-of-gravity in Y.		 real 4 pixels   POS_PLATE_Y
Y_BJ grs_ngpSource, grs_ranSource, grs_sgpSource TWODFGRS Plate y_bj in 8 micron pixels real 4      
y_coadd twomass_xsc 2MASS y (in-scan) position (coadd coord.). real 4 arcsec   INST_POS
Y_IMAGE mgcDetection MGC Object y position real 4 pixel    
Y_OFF mgcGalaxyStruct MGC Y offset of Galaxy Centre real 4   99.99  
Y_OFFm mgcGalaxyStruct MGC Y offset error (-) real 4   99.99  
Y_OFFp mgcGalaxyStruct MGC Y offset error (+) real 4   99.99  
Y_R spectra SIXDF y position of object from R frame int 4      
Y_V spectra SIXDF y position of object from V frame int 4      
yAperMag1 vmcSynopticSource VSAQC Extended source Y aperture corrected mag (0.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag1 vmcSynopticSource VSAVMC Extended source Y aperture corrected mag (0.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag1 vvvSource VSAQC Extended source Y aperture corrected mag (0.7 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag1 vvvSource VSAVVV Extended source Y aperture corrected mag (0.7 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag1Err vmcSynopticSource VSAQC Error in extended source Y mag (0.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag1Err vmcSynopticSource VSAVMC Error in extended source Y mag (0.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag1Err vvvSource VSAQC Error in extended source Y mag (1.4 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag1Err vvvSource VSAVVV Error in extended source Y mag (1.4 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag2 vmcSynopticSource VSAQC Extended source Y aperture corrected mag (1.4 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag2 vmcSynopticSource VSAVMC Extended source Y aperture corrected mag (1.4 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag2Err vmcSynopticSource VSAQC Error in extended source Y mag (1.4 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag2Err vmcSynopticSource VSAVMC Error in extended source Y mag (1.4 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag3 svNgc253Source VSASVNGC253 Default point/extended source Y aperture corrected mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 svOrionSource VSASVORION Default point/extended source Y aperture corrected mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 ultravistaSource VSAUltraVISTA Default point/extended source Y mag, no aperture correction applied
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 ultravistaSource, videoSource VSAQC Default point/extended source Y mag, no aperture correction applied
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 vhsSource VSAVHS Default point source Y aperture corrected mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 vhsSource, vikingSource, vmcSource VSAQC Default point source Y aperture corrected mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 vmcSynopticSource VSAQC Default point/extended source Y aperture corrected mag (2.0 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 vmcSynopticSource VSAVMC Default point/extended source Y aperture corrected mag (2.0 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 vvvSource VSAQC Default point/extended source Y aperture corrected mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3 vvvSource VSAVVV Default point/extended source Y aperture corrected mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMag3Err svNgc253Source VSASVNGC253 Error in default point/extended source Y mag (2.0 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag3Err svOrionSource VSASVORION Error in default point/extended source Y mag (2.0 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag3Err ultravistaSource VSAUltraVISTA Error in default point/extended source Y mag (2.0 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag3Err ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource, vmcSynopticSource, vvvSource VSAQC Error in default point/extended source Y mag (2.0 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag4 svNgc253Source VSASVNGC253 Extended source Y aperture corrected mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4 svOrionSource VSASVORION Extended source Y aperture corrected mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4 ultravistaSource VSAUltraVISTA Extended source Y mag, no aperture correction applied real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4 ultravistaSource, videoSource VSAQC Extended source Y mag, no aperture correction applied real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4 vhsSource VSAVHS Point source Y aperture corrected mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4 vhsSource, vikingSource, vmcSource VSAQC Point source Y aperture corrected mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4 vmcSynopticSource VSAVMC Extended source Y aperture corrected mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4 vmcSynopticSource, vvvSource VSAQC Extended source Y aperture corrected mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag4Err svNgc253Source VSASVNGC253 Error in extended source Y mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag4Err svOrionSource VSASVORION Error in extended source Y mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag4Err ultravistaSource VSAUltraVISTA Error in extended source Y mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag4Err ultravistaSource, videoSource, vmcSynopticSource, vvvSource VSAQC Error in extended source Y mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag4Err vhsSource VSAVHS Error in point/extended source Y mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag4Err vhsSource, vikingSource, vmcSource VSAQC Error in point/extended source Y mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag5 vmcSynopticSource VSAQC Extended source Y aperture corrected mag (4.0 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag5 vmcSynopticSource VSAVMC Extended source Y aperture corrected mag (4.0 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag5Err vmcSynopticSource VSAQC Error in extended source Y mag (4.0 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag5Err vmcSynopticSource VSAVMC Error in extended source Y mag (4.0 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag6 svNgc253Source VSASVNGC253 Extended source Y aperture corrected mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag6 svOrionSource VSASVORION Extended source Y aperture corrected mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag6 ultravistaSource VSAUltraVISTA Extended source Y mag, no aperture correction applied real 4 mag -0.9999995e9 PHOT_MAG
yAperMag6 ultravistaSource, videoSource VSAQC Extended source Y mag, no aperture correction applied real 4 mag -0.9999995e9 PHOT_MAG
yAperMag6 vhsSource VSAVHS Point source Y aperture corrected mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag6 vhsSource, vikingSource, vmcSource VSAQC Point source Y aperture corrected mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMag6Err svNgc253Source VSASVNGC253 Error in extended source Y mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag6Err svOrionSource VSASVORION Error in extended source Y mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag6Err ultravistaSource VSAUltraVISTA Error in extended source Y mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag6Err ultravistaSource, videoSource VSAQC Error in extended source Y mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag6Err vhsSource VSAVHS Error in point/extended source Y mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMag6Err vhsSource, vikingSource, vmcSource VSAQC Error in point/extended source Y mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 ERROR
yAperMagNoAperCorr3 vhsSource VSAVHS Default extended source Y aperture mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMagNoAperCorr3 vhsSource, vikingSource, vmcSource VSAQC Default extended source Y aperture mag (2.0 arcsec aperture diameter)
If in doubt use this flux estimator		 real 4 mag -0.9999995e9 PHOT_MAG
yAperMagNoAperCorr4 vhsSource VSAVHS Extended source Y aperture mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMagNoAperCorr4 vhsSource, vikingSource, vmcSource VSAQC Extended source Y aperture mag (2.8 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMagNoAperCorr6 vhsSource VSAVHS Extended source Y aperture mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yAperMagNoAperCorr6 vhsSource, vikingSource, vmcSource VSAQC Extended source Y aperture mag (5.7 arcsec aperture diameter) real 4 mag -0.9999995e9 PHOT_MAG
yaStratAst videoVarFrameSetInfo VSAVIDEO Strateva parameter, a, in fit to astrometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
yaStratAst videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Strateva parameter, a, in fit to astrometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
yaStratPht videoVarFrameSetInfo VSAVIDEO Strateva parameter, a, in fit to photometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
yaStratPht videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Strateva parameter, a, in fit to photometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
yAverageConf svNgc253Source VSASVNGC253 average confidence in 2 arcsec diameter default aperture (aper3) Y real 4   -99999999 CODE_MISC
yAverageConf svOrionSource VSASVORION average confidence in 2 arcsec diameter default aperture (aper3) Y real 4   -99999999 CODE_MISC
yAverageConf vhsSource VSAVHS average confidence in 2 arcsec diameter default aperture (aper3) Y real 4   -99999999 CODE_MISC
yAverageConf vhsSource, vikingSource, vmcSource, vmcSynopticSource VSAQC average confidence in 2 arcsec diameter default aperture (aper3) Y real 4   -99999999 CODE_MISC
ybestAper videoVariability VSAVIDEO Best aperture (1-6) for photometric statistics in the Y band int 4   -9999  
Aperture magnitude (1-6) which gives the lowest RMS for the object. All apertures have the appropriate aperture correction. This can give better values in crowded regions than aperMag3 (see Irwin et al. 2007, MNRAS, 375, 1449)
ybestAper videoVariability, vikingVariability, vmcVariability VSAQC Best aperture (1-6) for photometric statistics in the Y band int 4   -9999  
Aperture magnitude (1-6) which gives the lowest RMS for the object. All apertures have the appropriate aperture correction. This can give better values in crowded regions than aperMag3 (see Irwin et al. 2007, MNRAS, 375, 1449)
ybStratAst videoVarFrameSetInfo VSAVIDEO Strateva parameter, b, in fit to astrometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ybStratAst videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Strateva parameter, b, in fit to astrometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ybStratPht videoVarFrameSetInfo VSAVIDEO Strateva parameter, b, in fit to photometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
ybStratPht videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Strateva parameter, b, in fit to photometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
ychiSqAst videoVarFrameSetInfo VSAVIDEO Goodness of fit of Strateva function to astrometric data in Y band real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ychiSqAst videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Goodness of fit of Strateva function to astrometric data in Y band real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ychiSqpd videoVariability VSAVIDEO Chi square (per degree of freedom) fit to data (mean and expected rms) real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ychiSqpd videoVariability, vikingVariability, vmcVariability VSAQC Chi square (per degree of freedom) fit to data (mean and expected rms) real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ychiSqPht videoVarFrameSetInfo VSAVIDEO Goodness of fit of Strateva function to photometric data in Y band real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
ychiSqPht videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Goodness of fit of Strateva function to photometric data in Y band real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
yClass svNgc253Source VSASVNGC253 discrete image classification flag in Y smallint 2   -9999 CLASS_MISC
yClass svOrionSource VSASVORION discrete image classification flag in Y smallint 2   -9999 CLASS_MISC
yClass ultravistaSource VSAUltraVISTA discrete image classification flag in Y smallint 2   -9999 CLASS_MISC
yClass ultravistaSource, ultravistaSourceRemeasurement, vhsSource, vhsSourceRemeasurement, videoSource, videoSourceRemeasurement, vikingSource, vikingSourceRemeasurement, vmcSource, vmcSourceRemeasurement, vmcSynopticSource, vvvSource, vvvSourceRemeasurement VSAQC discrete image classification flag in Y smallint 2   -9999 CLASS_MISC
yClassStat svNgc253Source VSASVNGC253 N(0,1) stellarness-of-profile statistic in Y real 4   -0.9999995e9 STAT_PROP
yClassStat svOrionSource VSASVORION N(0,1) stellarness-of-profile statistic in Y real 4   -0.9999995e9 STAT_PROP
yClassStat ultravistaSource VSAUltraVISTA S-Extractor classification statistic in Y real 4   -0.9999995e9 STAT_PROP
yClassStat ultravistaSource, videoSource, vvvSource VSAQC S-Extractor classification statistic in Y real 4   -0.9999995e9 STAT_PROP
yClassStat ultravistaSourceRemeasurement VSAUltraVISTA N(0,1) stellarness-of-profile statistic in Y real 4   -0.9999995e9 STAT_PROP
yClassStat ultravistaSourceRemeasurement, vhsSource, vhsSourceRemeasurement, videoSourceRemeasurement, vikingSource, vikingSourceRemeasurement, vmcSource, vmcSourceRemeasurement, vmcSynopticSource, vvvSourceRemeasurement VSAQC N(0,1) stellarness-of-profile statistic in Y real 4   -0.9999995e9 STAT_PROP
ycStratAst videoVarFrameSetInfo VSAVIDEO Strateva parameter, c, in fit to astrometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ycStratAst videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Strateva parameter, c, in fit to astrometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ycStratPht videoVarFrameSetInfo VSAVIDEO Strateva parameter, c, in fit to photometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
ycStratPht videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Strateva parameter, c, in fit to photometric rms vs magnitude in Y band, see Sesar et al. 2007. real 4   -0.9999995e9  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
yDeblend ultravistaSource VSAUltraVISTA placeholder flag indicating parent/child relation in Y int 4   -99999999 CODE_MISC
yDeblend ultravistaSource, ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSource, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSource, vvvSourceRemeasurement VSAQC placeholder flag indicating parent/child relation in Y int 4   -99999999 CODE_MISC
yEll svNgc253Source VSASVNGC253 1-b/a, where a/b=semi-major/minor axes in Y real 4   -0.9999995e9 PHYS_ELLIPTICITY
yEll svOrionSource VSASVORION 1-b/a, where a/b=semi-major/minor axes in Y real 4   -0.9999995e9 PHYS_ELLIPTICITY
yEll ultravistaSource VSAUltraVISTA 1-b/a, where a/b=semi-major/minor axes in Y real 4   -0.9999995e9 PHYS_ELLIPTICITY
yEll ultravistaSource, ultravistaSourceRemeasurement, vhsSource, vhsSourceRemeasurement, videoSource, videoSourceRemeasurement, vikingSource, vikingSourceRemeasurement, vmcSource, vmcSourceRemeasurement, vmcSynopticSource, vvvSource, vvvSourceRemeasurement VSAQC 1-b/a, where a/b=semi-major/minor axes in Y real 4   -0.9999995e9 PHYS_ELLIPTICITY
yeNum svNgc253MergeLog VSASVNGC253 the extension number of this Y frame tinyint 1     NUMBER
yeNum svOrionMergeLog VSASVORION the extension number of this Y frame tinyint 1     NUMBER
yeNum ultravistaMergeLog VSAUltraVISTA the extension number of this Y frame tinyint 1     NUMBER
yeNum ultravistaMergeLog, vhsMergeLog, videoMergeLog, vikingMergeLog, vmcMergeLog, vmcSynopticMergeLog, vvvMergeLog VSAQC the extension number of this Y frame tinyint 1     NUMBER
yErr svNgc253Detection VSASVNGC253 Error in Y coordinate {catalogue TType keyword: Y_coordinate_err}
Estimate of centroid error.		 real 4 pixels   ERROR
yErr svOrionDetection VSASVORION Error in Y coordinate {catalogue TType keyword: Y_coordinate_err}
Estimate of centroid error.		 real 4 pixels   ERROR
yErr ultravistaDetection VSAUltraVISTA Error in Y coordinate (SE: ERRY2_IMAGE½) {catalogue TType keyword: Y_coordinate_err}
Estimate of centroid error.		 real 4 pixels   ERROR
yErr ultravistaDetection, videoDetection VSAQC Error in Y coordinate (SE: ERRY2_IMAGE½) {catalogue TType keyword: Y_coordinate_err}
Estimate of centroid error.		 real 4 pixels   ERROR
yErr ultravistaListRemeasurement VSAUltraVISTA Error in Y coordinate {catalogue TType keyword: Y_coordinate_err}
Estimate of centroid error.		 real 4 pixels   ERROR
yErr ultravistaListRemeasurement, vhsDetection, vhsListRemeasurement, videoListRemeasurement, vikingDetection, vikingListRemeasurement, vmcDetection, vmcListRemeasurement, vvvDetection, vvvListRemeasurement VSAQC Error in Y coordinate {catalogue TType keyword: Y_coordinate_err}
Estimate of centroid error.		 real 4 pixels   ERROR
YERR_R spectra SIXDF error on Y_R position int 4      
YERR_V spectra SIXDF error on Y_V position int 4      
yErrBits svNgc253Source VSASVNGC253 processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
Apparently not actually an error bit flag, but a count of the number of zero confidence pixels in the default (2 arcsec diameter) aperture.
yErrBits svOrionSource VSASVORION processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
Apparently not actually an error bit flag, but a count of the number of zero confidence pixels in the default (2 arcsec diameter) aperture.
yErrBits ultravistaSource VSAUltraVISTA processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
This uses the FLAGS attribute in SE. The individual bit flags that this can be decomposed into are as follows:
Bit FlagMeaning
1The object has neighbours, bright enough and close enough to significantly bias the MAG_AUTO photometry or bad pixels (more than 10% of photometry affected).
2The object was originally blended with another
4At least one pixel is saturated (or very close to)
8The object is truncated (too close to an image boundary)
16Object's aperture data are incomplete or corrupted
32Object's isophotal data are imcomplete or corrupted. This is an old flag inherited from SE v1.0, and is kept for compatability reasons. It doesn't have any consequence for the extracted parameters.
64Memory overflow occurred during deblending
128Memory overflow occurred during extraction

yErrBits ultravistaSource, videoSource VSAQC processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
This uses the FLAGS attribute in SE. The individual bit flags that this can be decomposed into are as follows:
Bit FlagMeaning
1The object has neighbours, bright enough and close enough to significantly bias the MAG_AUTO photometry or bad pixels (more than 10% of photometry affected).
2The object was originally blended with another
4At least one pixel is saturated (or very close to)
8The object is truncated (too close to an image boundary)
16Object's aperture data are incomplete or corrupted
32Object's isophotal data are imcomplete or corrupted. This is an old flag inherited from SE v1.0, and is kept for compatability reasons. It doesn't have any consequence for the extracted parameters.
64Memory overflow occurred during deblending
128Memory overflow occurred during extraction

yErrBits ultravistaSourceRemeasurement VSAUltraVISTA processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
yErrBits ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSourceRemeasurement VSAQC processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
yErrBits vhsSource VSAVHS processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
Apparently not actually an error bit flag, but a count of the number of zero confidence pixels in the default (2 arcsec diameter) aperture.
yErrBits vhsSource, vikingSource, vmcSource, vmcSynopticSource, vvvSource VSAQC processing warning/error bitwise flags in Y int 4   -99999999 CODE_MISC
Apparently not actually an error bit flag, but a count of the number of zero confidence pixels in the default (2 arcsec diameter) aperture.
yEta svNgc253Source VSASVNGC253 Offset of Y detection from master position (+north/-south) real 4 arcsec -0.9999995e9 POS_EQ_DEC_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
yEta svOrionSource VSASVORION Offset of Y detection from master position (+north/-south) real 4 arcsec -0.9999995e9 POS_EQ_DEC_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
yEta ultravistaSource VSAUltraVISTA Offset of Y detection from master position (+north/-south) real 4 arcsec -0.9999995e9 POS_EQ_DEC_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
yEta ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource, vmcSynopticSource, vvvSource VSAQC Offset of Y detection from master position (+north/-south) real 4 arcsec -0.9999995e9 POS_EQ_DEC_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
yexpML videoVarFrameSetInfo VSAVIDEO Expected magnitude limit of frameSet in this in Y band. real 4   -0.9999995e9  
yexpML videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Expected magnitude limit of frameSet in this in Y band. real 4   -0.9999995e9  
yExpRms videoVariability VSAVIDEO Rms calculated from polynomial fit to modal RMS as a function of magnitude in Y band real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yExpRms videoVariability, vikingVariability, vmcVariability VSAQC Rms calculated from polynomial fit to modal RMS as a function of magnitude in Y band real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yGausig svNgc253Source VSASVNGC253 RMS of axes of ellipse fit in Y real 4 pixels -0.9999995e9 MORPH_PARAM
yGausig svOrionSource VSASVORION RMS of axes of ellipse fit in Y real 4 pixels -0.9999995e9 MORPH_PARAM
yGausig ultravistaSource VSAUltraVISTA RMS of axes of ellipse fit in Y real 4 pixels -0.9999995e9 MORPH_PARAM
yGausig ultravistaSource, ultravistaSourceRemeasurement, vhsSource, vhsSourceRemeasurement, videoSource, videoSourceRemeasurement, vikingSource, vikingSourceRemeasurement, vmcSource, vmcSourceRemeasurement, vmcSynopticSource, vvvSource, vvvSourceRemeasurement VSAQC RMS of axes of ellipse fit in Y real 4 pixels -0.9999995e9 MORPH_PARAM
yHlCorSMjRadAs svNgc253Source VSASVNGC253 Seeing corrected half-light, semi-major axis in Y band real 4 arcsec -0.9999995e9 EXTENSION_RAD
yHlCorSMjRadAs ultravistaSource VSAUltraVISTA Seeing corrected half-light, semi-major axis in Y band real 4 arcsec -0.9999995e9 EXTENSION_RAD
yHlCorSMjRadAs ultravistaSource, vhsSource, videoSource, vikingSource VSAQC Seeing corrected half-light, semi-major axis in Y band real 4 arcsec -0.9999995e9 EXTENSION_RAD
yIntRms videoVariability VSAVIDEO Intrinsic rms in Y-band real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yIntRms videoVariability, vikingVariability, vmcVariability VSAQC Intrinsic rms in Y-band real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yjiWS vmcVariability VSAQC Welch-Stetson statistic between Y and J. This assumes colour does not vary much and helps remove variation due to a few poor detections real 4   -0.9999995e9  
The Welch-Stetson statistic is a measure of the correlation of the variability between two bands. We use the calculation in Welch D.L. and Stetson P.B. 1993, AJ, 105, 5, which is also used in Sesar et al. 2007, AJ, 134, 2236. We use the aperMag3 magnitude when comparing between bands.
yjiWS vmcVariability VSAVMC Welch-Stetson statistic between Y and J. This assumes colour does not vary much and helps remove variation due to a few poor detections real 4   -0.9999995e9  
The Welch-Stetson statistic is a measure of the correlation of the variability between two bands. We use the calculation in Welch D.L. and Stetson P.B. 1993, AJ, 105, 5, which is also used in Sesar et al. 2007, AJ, 134, 2236. We use the aperMag3 magnitude when comparing between bands.
yMag ultravistaSourceRemeasurement VSAUltraVISTA Y mag (as appropriate for this merged source) real 4 mag -0.9999995e9 PHOT_MAG
yMag ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSourceRemeasurement VSAQC Y mag (as appropriate for this merged source) real 4 mag -0.9999995e9 PHOT_MAG
yMagErr ultravistaSourceRemeasurement VSAUltraVISTA Error in Y mag real 4 mag -0.9999995e9 ERROR
yMagErr ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSourceRemeasurement VSAQC Error in Y mag real 4 mag -0.9999995e9 ERROR
yMagMAD videoVariability VSAVIDEO Median Absolute Deviation of Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yMagMAD videoVariability, vikingVariability, vmcVariability VSAQC Median Absolute Deviation of Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yMagRms videoVariability VSAVIDEO rms of Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yMagRms videoVariability, vikingVariability, vmcVariability VSAQC rms of Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ymaxCadence videoVariability VSAVIDEO maximum gap between observations real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ymaxCadence videoVariability, vikingVariability, vmcVariability VSAQC maximum gap between observations real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
yMaxMag videoVariability VSAVIDEO Maximum magnitude in Y band, of good detections real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yMaxMag videoVariability, vikingVariability, vmcVariability VSAQC Maximum magnitude in Y band, of good detections real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ymeanMag videoVariability VSAVIDEO Mean Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ymeanMag videoVariability, vikingVariability, vmcVariability VSAQC Mean Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ymedCadence videoVariability VSAVIDEO median gap between observations real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ymedCadence videoVariability, vikingVariability, vmcVariability VSAQC median gap between observations real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ymedianMag videoVariability VSAVIDEO Median Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ymedianMag videoVariability, vikingVariability, vmcVariability VSAQC Median Y magnitude real 4 mag -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ymfID svNgc253MergeLog VSASVNGC253 the UID of the relevant Y multiframe bigint 8     ID_FRAME
ymfID svOrionMergeLog VSASVORION the UID of the relevant Y multiframe bigint 8     ID_FRAME
ymfID ultravistaMergeLog VSAUltraVISTA the UID of the relevant Y multiframe bigint 8     ID_FRAME
ymfID ultravistaMergeLog, vhsMergeLog, videoMergeLog, vikingMergeLog, vmcMergeLog, vmcSynopticMergeLog, vvvMergeLog VSAQC the UID of the relevant Y multiframe bigint 8     ID_FRAME
yminCadence videoVariability VSAVIDEO minimum gap between observations real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
yminCadence videoVariability, vikingVariability, vmcVariability VSAQC minimum gap between observations real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
yMinMag videoVariability VSAVIDEO Minimum magnitude in Y band, of good detections real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yMinMag videoVariability, vikingVariability, vmcVariability VSAQC Minimum magnitude in Y band, of good detections real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ymj ultravistaSourceRemeasurement VSAUltraVISTA Default colour Y-J (using appropriate mags) real 4 mag   PHOT_COLOR
ymj ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSourceRemeasurement VSAQC Default colour Y-J (using appropriate mags) real 4 mag   PHOT_COLOR
ymjErr ultravistaSourceRemeasurement VSAUltraVISTA Error on colour Y-J real 4 mag   ERROR
ymjErr ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSourceRemeasurement VSAQC Error on colour Y-J real 4 mag   ERROR
ymjExt svNgc253Source VSASVNGC253 Extended source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExt svOrionSource VSASVORION Extended source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExt ultravistaSource VSAUltraVISTA Extended source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExt ultravistaSource, videoSource, vvvSource VSAQC Extended source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExt vhsSource VSAVHS Extended source colour Y-J (using aperMagNoAperCorr3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExt vhsSource, vikingSource, vmcSource VSAQC Extended source colour Y-J (using aperMagNoAperCorr3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExtErr svNgc253Source VSASVNGC253 Error on extended source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExtErr svOrionSource VSASVORION Error on extended source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExtErr ultravistaSource VSAUltraVISTA Error on extended source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjExtErr ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource, vvvSource VSAQC Error on extended source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPnt svNgc253Source VSASVNGC253 Point source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPnt svOrionSource VSASVORION Point source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPnt ultravistaSource VSAUltraVISTA Point source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPnt ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource, vmcSynopticSource, vvvSource VSAQC Point source colour Y-J (using aperMag3) real 4 mag -0.9999995e9 PHOT_COLOR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPntErr svNgc253Source VSASVNGC253 Error on point source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPntErr svOrionSource VSASVORION Error on point source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPntErr ultravistaSource VSAUltraVISTA Error on point source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
ymjPntErr ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource, vmcSynopticSource, vvvSource VSAQC Error on point source colour Y-J real 4 mag -0.9999995e9 ERROR
Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
yndof videoVariability VSAVIDEO Number of degrees of freedom for chisquare smallint 2   -9999  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yndof videoVariability, vikingVariability, vmcVariability VSAQC Number of degrees of freedom for chisquare smallint 2   -9999  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ynDofAst videoVarFrameSetInfo VSAVIDEO Number of degrees of freedom of astrometric fit in Y band. smallint 2   -9999  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ynDofAst videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Number of degrees of freedom of astrometric fit in Y band. smallint 2   -9999  
The best fit solution to the expected RMS position around the mean for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated.
ynDofPht videoVarFrameSetInfo VSAVIDEO Number of degrees of freedom of photometric fit in Y band. smallint 2   -9999  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
ynDofPht videoVarFrameSetInfo, vikingVarFrameSetInfo, vmcVarFrameSetInfo VSAQC Number of degrees of freedom of photometric fit in Y band. smallint 2   -9999  
The best fit solution to the expected RMS brightness (in magnitudes) for all objects in the frameset. Objects were binned in ranges of magnitude and the median RMS (after clipping out variable objects using the median-absolute deviation) was calculated. The Strateva function $\zeta(m)>=a+b\,10^{0.4m}+c\,10^{0.8m}$ was fit, where $\zeta(m)$ is the expected RMS as a function of magnitude. The chi-squared and number of degrees of freedom are also calculated. This technique was used in Sesar et al. 2007, AJ, 134, 2236.
ynFlaggedObs videoVariability VSAQC Number of detections in Y band flagged as potentially spurious by videoDetection.ppErrBits int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynFlaggedObs videoVariability VSAVIDEO Number of detections in Y band flagged as potentially spurious by videoDetection.ppErrBits int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynFlaggedObs vikingVariability VSAQC Number of detections in Y band flagged as potentially spurious by vikingDetection.ppErrBits int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynFlaggedObs vikingVariability VSAVIKING Number of detections in Y band flagged as potentially spurious by vikingDetection.ppErrBits int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynFlaggedObs vmcVariability VSAQC Number of detections in Y band flagged as potentially spurious by vmcDetection.ppErrBits int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynFlaggedObs vmcVariability VSAVMC Number of detections in Y band flagged as potentially spurious by vmcDetection.ppErrBits int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynGoodObs videoVariability VSAVIDEO Number of good detections in Y band int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynGoodObs videoVariability, vikingVariability, vmcVariability VSAQC Number of good detections in Y band int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
yNgt3sig videoVariability VSAVIDEO Number of good detections in Y-band that are more than 3 sigma deviations smallint 2   -9999  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yNgt3sig videoVariability, vikingVariability, vmcVariability VSAQC Number of good detections in Y-band that are more than 3 sigma deviations smallint 2   -9999  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ynMissingObs videoVariability VSAVIDEO Number of Y band frames that this object should have been detected on and was not int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ynMissingObs videoVariability, vikingVariability, vmcVariability VSAQC Number of Y band frames that this object should have been detected on and was not int 4   0  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
yPA svNgc253Source VSASVNGC253 ellipse fit celestial orientation in Y real 4 Degrees -0.9999995e9 POS_POS-ANG
yPA svOrionSource VSASVORION ellipse fit celestial orientation in Y real 4 Degrees -0.9999995e9 POS_POS-ANG
yPA ultravistaSource VSAUltraVISTA ellipse fit celestial orientation in Y real 4 Degrees -0.9999995e9 POS_POS-ANG
yPA ultravistaSource, ultravistaSourceRemeasurement, vhsSource, vhsSourceRemeasurement, videoSource, videoSourceRemeasurement, vikingSource, vikingSourceRemeasurement, vmcSource, vmcSourceRemeasurement, vmcSynopticSource, vvvSource, vvvSourceRemeasurement VSAQC ellipse fit celestial orientation in Y real 4 Degrees -0.9999995e9 POS_POS-ANG
yPetroMag svNgc253Source VSASVNGC253 Extended source Y mag (Petrosian) real 4 mag -0.9999995e9 PHOT_MAG
yPetroMag svOrionSource VSASVORION Extended source Y mag (Petrosian) real 4 mag -0.9999995e9 PHOT_MAG
yPetroMag ultravistaSource VSAUltraVISTA Extended source Y mag (Petrosian) real 4 mag -0.9999995e9 PHOT_MAG
yPetroMag ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource VSAQC Extended source Y mag (Petrosian) real 4 mag -0.9999995e9 PHOT_MAG
yPetroMagErr svNgc253Source VSASVNGC253 Error in extended source Y mag (Petrosian) real 4 mag -0.9999995e9 ERROR
yPetroMagErr svOrionSource VSASVORION Error in extended source Y mag (Petrosian) real 4 mag -0.9999995e9 ERROR
yPetroMagErr ultravistaSource VSAUltraVISTA Error in extended source Y mag (Petrosian) real 4 mag -0.9999995e9 ERROR
yPetroMagErr ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource VSAQC Error in extended source Y mag (Petrosian) real 4 mag -0.9999995e9 ERROR
yPixSize CurrentAstrometry VSASVNGC253 Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize CurrentAstrometry VSASVORION Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize CurrentAstrometry VSAUltraVISTA Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize CurrentAstrometry VSAVHS Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize CurrentAstrometry VSAVIDEO Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize CurrentAstrometry VSAVIKING Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize CurrentAstrometry VSAVMC Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize CurrentAstrometry VSAVVV Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPixSize ultravistaCurrentAstrometry, vhsCurrentAstrometry, videoCurrentAstrometry, vikingCurrentAstrometry, vmcCurrentAstrometry, vvvCurrentAstrometry VSAQC Angular size of pixels in Y real 4 Arcseconds -0.9999995e9 POS_ANG_DIST_GENERAL
yPos nvssSource NVSS Y position (Dec direction) of the radio source real 4 pixels   POS_CCD_Y
yppErrBits svNgc253Source VSASVNGC253 additional WFAU post-processing error bits in Y int 4   0 CODE_MISC
Post-processing error quality bit flags assigned to detections in the archive curation procedure for survey data. From least to most significant byte in the 4-byte integer attribute byte 0 (bits 0 to 7) corresponds to information on generally innocuous conditions that are nonetheless potentially significant as regards the integrity of that detection; byte 1 (bits 8 to 15) corresponds to warnings; byte 2 (bits 16 to 23) corresponds to important warnings; and finally byte 3 (bits 24 to 31) corresponds to severe warnings:
ByteBitDetection quality issue Threshold or bit mask Applies to
DecimalHexadecimal
0 4 Deblended 16 0x00000010 All VDFS catalogues
0 6 Bad pixel(s) in default aperture 64 0x00000040 All VDFS catalogues
2 16 Close to saturated 65536 0x00010000 All VDFS catalogues
2 17 Photometric calibration probably subject to systematic error 131072 0x00020000 VVV only
2 22 Lies within a dither offset of the stacked frame boundary 4194304 0x00400000 All catalogues
2 23 Lies within the underexposed strip (or "ear") of a tile 8388608 0x00800000 All catalogues from tiles

In this way, the higher the error quality bit flag value, the more likely it is that the detection is spurious. The decimal threshold (column 4) gives the minimum value of the quality flag for a detection having the given condition (since other bits in the flag may be set also; the corresponding hexadecimal value, where each digit corresponds to 4 bits in the flag, can be easier to compute when writing SQL queries to test for a given condition). For example, to exclude all Ks band sources in the VHS having any error quality condition other than informational ones, include a predicate ... AND kppErrBits ≤ 255. See the SQL Cookbook and other online pages for further information.
yppErrBits svOrionSource VSASVORION additional WFAU post-processing error bits in Y int 4   0 CODE_MISC
Post-processing error quality bit flags assigned to detections in the archive curation procedure for survey data. From least to most significant byte in the 4-byte integer attribute byte 0 (bits 0 to 7) corresponds to information on generally innocuous conditions that are nonetheless potentially significant as regards the integrity of that detection; byte 1 (bits 8 to 15) corresponds to warnings; byte 2 (bits 16 to 23) corresponds to important warnings; and finally byte 3 (bits 24 to 31) corresponds to severe warnings:
ByteBitDetection quality issue Threshold or bit mask Applies to
DecimalHexadecimal
0 4 Deblended 16 0x00000010 All VDFS catalogues
0 6 Bad pixel(s) in default aperture 64 0x00000040 All VDFS catalogues
2 16 Close to saturated 65536 0x00010000 All VDFS catalogues
2 17 Photometric calibration probably subject to systematic error 131072 0x00020000 VVV only
2 22 Lies within a dither offset of the stacked frame boundary 4194304 0x00400000 All catalogues
2 23 Lies within the underexposed strip (or "ear") of a tile 8388608 0x00800000 All catalogues from tiles

In this way, the higher the error quality bit flag value, the more likely it is that the detection is spurious. The decimal threshold (column 4) gives the minimum value of the quality flag for a detection having the given condition (since other bits in the flag may be set also; the corresponding hexadecimal value, where each digit corresponds to 4 bits in the flag, can be easier to compute when writing SQL queries to test for a given condition). For example, to exclude all Ks band sources in the VHS having any error quality condition other than informational ones, include a predicate ... AND kppErrBits ≤ 255. See the SQL Cookbook and other online pages for further information.
yppErrBits ultravistaSource VSAUltraVISTA additional WFAU post-processing error bits in Y int 4   0 CODE_MISC
yppErrBits ultravistaSource, ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSource, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSource, vvvSourceRemeasurement VSAQC additional WFAU post-processing error bits in Y int 4   0 CODE_MISC
yppErrBits vhsSource VSAVHS additional WFAU post-processing error bits in Y int 4   0 CODE_MISC
Post-processing error quality bit flags assigned to detections in the archive curation procedure for survey data. From least to most significant byte in the 4-byte integer attribute byte 0 (bits 0 to 7) corresponds to information on generally innocuous conditions that are nonetheless potentially significant as regards the integrity of that detection; byte 1 (bits 8 to 15) corresponds to warnings; byte 2 (bits 16 to 23) corresponds to important warnings; and finally byte 3 (bits 24 to 31) corresponds to severe warnings:
ByteBitDetection quality issue Threshold or bit mask Applies to
DecimalHexadecimal
0 4 Deblended 16 0x00000010 All VDFS catalogues
0 6 Bad pixel(s) in default aperture 64 0x00000040 All VDFS catalogues
2 16 Close to saturated 65536 0x00010000 All VDFS catalogues
2 17 Photometric calibration probably subject to systematic error 131072 0x00020000 VVV only
2 22 Lies within a dither offset of the stacked frame boundary 4194304 0x00400000 All catalogues
2 23 Lies within the underexposed strip (or "ear") of a tile 8388608 0x00800000 All catalogues from tiles

In this way, the higher the error quality bit flag value, the more likely it is that the detection is spurious. The decimal threshold (column 4) gives the minimum value of the quality flag for a detection having the given condition (since other bits in the flag may be set also; the corresponding hexadecimal value, where each digit corresponds to 4 bits in the flag, can be easier to compute when writing SQL queries to test for a given condition). For example, to exclude all Ks band sources in the VHS having any error quality condition other than informational ones, include a predicate ... AND kppErrBits ≤ 255. See the SQL Cookbook and other online pages for further information.
yppErrBits vhsSource, vikingSource, vmcSource, vmcSynopticSource VSAQC additional WFAU post-processing error bits in Y int 4   0 CODE_MISC
Post-processing error quality bit flags assigned to detections in the archive curation procedure for survey data. From least to most significant byte in the 4-byte integer attribute byte 0 (bits 0 to 7) corresponds to information on generally innocuous conditions that are nonetheless potentially significant as regards the integrity of that detection; byte 1 (bits 8 to 15) corresponds to warnings; byte 2 (bits 16 to 23) corresponds to important warnings; and finally byte 3 (bits 24 to 31) corresponds to severe warnings:
ByteBitDetection quality issue Threshold or bit mask Applies to
DecimalHexadecimal
0 4 Deblended 16 0x00000010 All VDFS catalogues
0 6 Bad pixel(s) in default aperture 64 0x00000040 All VDFS catalogues
2 16 Close to saturated 65536 0x00010000 All VDFS catalogues
2 17 Photometric calibration probably subject to systematic error 131072 0x00020000 VVV only
2 22 Lies within a dither offset of the stacked frame boundary 4194304 0x00400000 All catalogues
2 23 Lies within the underexposed strip (or "ear") of a tile 8388608 0x00800000 All catalogues from tiles

In this way, the higher the error quality bit flag value, the more likely it is that the detection is spurious. The decimal threshold (column 4) gives the minimum value of the quality flag for a detection having the given condition (since other bits in the flag may be set also; the corresponding hexadecimal value, where each digit corresponds to 4 bits in the flag, can be easier to compute when writing SQL queries to test for a given condition). For example, to exclude all Ks band sources in the VHS having any error quality condition other than informational ones, include a predicate ... AND kppErrBits ≤ 255. See the SQL Cookbook and other online pages for further information.
yprobVar videoVariability VSAVIDEO Probability of variable from chi-square (and other data) real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yprobVar videoVariability, vikingVariability, vmcVariability VSAQC Probability of variable from chi-square (and other data) real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yPsfMag svNgc253Source VSASVNGC253 Point source profile-fitted Y mag real 4 mag -0.9999995e9 PHOT_MAG
yPsfMag svOrionSource VSASVORION Point source profile-fitted Y mag real 4 mag -0.9999995e9 PHOT_MAG
yPsfMag ultravistaSource VSAUltraVISTA Not available in SE output real 4 mag -0.9999995e9 PHOT_MAG
yPsfMag ultravistaSource, videoSource VSAQC Not available in SE output real 4 mag -0.9999995e9 PHOT_MAG
yPsfMag vhsSource VSAVHS Point source profile-fitted Y mag real 4 mag -0.9999995e9 PHOT_MAG
yPsfMag vhsSource, vikingSource, vmcSource VSAQC Point source profile-fitted Y mag real 4 mag -0.9999995e9 PHOT_MAG
yPsfMagErr svNgc253Source VSASVNGC253 Error in point source profile-fitted Y mag real 4 mag -0.9999995e9 ERROR
yPsfMagErr svOrionSource VSASVORION Error in point source profile-fitted Y mag real 4 mag -0.9999995e9 ERROR
yPsfMagErr ultravistaSource VSAUltraVISTA Not available in SE output real 4 mag -0.9999995e9 ERROR
yPsfMagErr ultravistaSource, videoSource VSAQC Not available in SE output real 4 mag -0.9999995e9 ERROR
yPsfMagErr vhsSource VSAVHS Error in point source profile-fitted Y mag real 4 mag -0.9999995e9 ERROR
yPsfMagErr vhsSource, vikingSource, vmcSource VSAQC Error in point source profile-fitted Y mag real 4 mag -0.9999995e9 ERROR
ySeqNum svNgc253Source VSASVNGC253 the running number of the Y detection int 4   -99999999 ID_NUMBER
ySeqNum svOrionSource VSASVORION the running number of the Y detection int 4   -99999999 ID_NUMBER
ySeqNum ultravistaSource VSAUltraVISTA the running number of the Y detection int 4   -99999999 ID_NUMBER
ySeqNum ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource, vmcSynopticSource, vvvSource VSAQC the running number of the Y detection int 4   -99999999 ID_NUMBER
ySeqNum ultravistaSourceRemeasurement VSAUltraVISTA the running number of the Y remeasurement int 4   -99999999 ID_NUMBER
ySeqNum ultravistaSourceRemeasurement, vhsSourceRemeasurement, videoSourceRemeasurement, vikingSourceRemeasurement, vmcSourceRemeasurement, vvvSourceRemeasurement VSAQC the running number of the Y remeasurement int 4   -99999999 ID_NUMBER
ySerMag2D svNgc253Source VSASVNGC253 Extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 PHOT_MAG
ySerMag2D svOrionSource VSASVORION Extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 PHOT_MAG
ySerMag2D ultravistaSource VSAUltraVISTA Not available in SE output real 4 mag -0.9999995e9 PHOT_MAG
ySerMag2D ultravistaSource, videoSource VSAQC Not available in SE output real 4 mag -0.9999995e9 PHOT_MAG
ySerMag2D vhsSource VSAVHS Extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 PHOT_MAG
ySerMag2D vhsSource, vikingSource, vmcSource VSAQC Extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 PHOT_MAG
ySerMag2DErr svNgc253Source VSASVNGC253 Error in extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 ERROR
ySerMag2DErr svOrionSource VSASVORION Error in extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 ERROR
ySerMag2DErr ultravistaSource VSAUltraVISTA Not available in SE output real 4 mag -0.9999995e9 ERROR
ySerMag2DErr ultravistaSource, videoSource VSAQC Not available in SE output real 4 mag -0.9999995e9 ERROR
ySerMag2DErr vhsSource VSAVHS Error in extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 ERROR
ySerMag2DErr vhsSource, vikingSource, vmcSource VSAQC Error in extended source Y mag (profile-fitted) real 4 mag -0.9999995e9 ERROR
ySize MultiframeDetector VSASVNGC253 Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize MultiframeDetector VSASVORION Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize MultiframeDetector VSAUltraVISTA Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize MultiframeDetector VSAVHS Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize MultiframeDetector VSAVIDEO Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize MultiframeDetector VSAVIKING Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize MultiframeDetector VSAVMC Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize MultiframeDetector VSAVVV Y-axis size of image {catalogue extension keyword:  NYOUT} int 4   -9999  
ySize ultravistaMultiframeDetector, vhsMultiframeDetector, videoMultiframeDetector, vikingMultiframeDetector, vmcMultiframeDetector, vvvMultiframeDetector VSAQC Y-axis size of image int 4   -9999  
yskewness videoVariability VSAVIDEO Skewness in Y band (see Sesar et al. 2007) real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yskewness videoVariability, vikingVariability, vmcVariability VSAQC Skewness in Y band (see Sesar et al. 2007) real 4   -0.9999995e9  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
ytotalPeriod videoVariability VSAVIDEO total period of observations (last obs-first obs) real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
ytotalPeriod videoVariability, vikingVariability, vmcVariability VSAQC total period of observations (last obs-first obs) real 4 days -0.9999995e9  
The observations are classified as good, flagged or missing. Flagged observations are ones where the object has a ppErrBit flag. Missing observations are observations of the part of the sky that include the position of the object, but had no detection. All the statistics are calculated from good observations. The cadence parameters give the minimum, median and maximum time between observations, which is useful to know if the data could be used to find a particular type of variable.
yVarClass videoVariability VSAVIDEO Classification of variability in this band smallint 2   -9999  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yVarClass videoVariability, vikingVariability, vmcVariability VSAQC Classification of variability in this band smallint 2   -9999  
The photometry is calculated for good observations in the best aperture. The mean, rms, median, median absolute deviation, minMag and maxMag are quite standard. The skewness is calculated as in Sesar et al. 2007, AJ, 134, 2236. The number of good detections that are more than 3 standard deviations can indicate a distribution with many outliers. In each frameset, the mean and rms are used to derive a fit to the expected rms as a function of magnitude. The parameters for the fit are stored in VarFrameSetInfo and the value for the source is in expRms. This is subtracted from the rms in quadrature to get the intrinsic rms: the variability of the object beyond the noise in the system. The chi-squared is calculated, assuming a non-variable object which has the noise from the expected-rms and mean calculated as above. The probVar statistic assumes a chi-squared distribution with the correct number of degrees of freedom. The varClass statistic is 1, if the probVar>0.9 and intrinsicRMS/expectedRMS>3.
yXi svNgc253Source VSASVNGC253 Offset of Y detection from master position (+east/-west) real 4 arcsec -0.9999995e9 POS_EQ_RA_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
yXi svOrionSource VSASVORION Offset of Y detection from master position (+east/-west) real 4 arcsec -0.9999995e9 POS_EQ_RA_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
yXi ultravistaSource VSAUltraVISTA Offset of Y detection from master position (+east/-west) real 4 arcsec -0.9999995e9 POS_EQ_RA_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
yXi ultravistaSource, vhsSource, videoSource, vikingSource, vmcSource, vmcSynopticSource, vvvSource VSAQC Offset of Y detection from master position (+east/-west) real 4 arcsec -0.9999995e9 POS_EQ_RA_OFF
When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 1.0 arcseconds is used. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the VHS, you might wish to insist that the offsets in the selected sample are all below 0.5 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.


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21/02/2011