Harvard Plate Collection Metcalf Telescope

DASCH
Digital Access to a Sky Century @ Harvard
A New Look at the Temporal Universe

Database Overview

The DASCH project data is currently organized in three MySQL databases: the scanner database, the photometry database, and the auxscanner database. The scanner database contains the logbook information and keeps track of the scanning and processing of plates. The photometry database stores the results of the photometry pipeline, which is implemented using tab-delimited ASCII Starbase Data Tables, and enables lightcurve plotting and statistical analysis of the photometry data. The auxscanner database contains miscellaneous secondary data derived from other tables and files to improve overall processing performance.

Scanner Database

The scanner database contains the following tables for management of the scanning process, support of the photometry pipeline, and support of this website.

globalContains global constants, control variables, and a time stamp.
locationsContains observatory latitudes, longitudes, and elevations.
ranges Associates plate series numbers with observatory locations and the expected time type (UT, EST, SAST,...) . Handles duplicate plate numbers.
series Contains a list all of the telescopes and their characteristics
classes Contains a lists all known plate classes
plates Contains a list of all known plates. Contains a record of low resolution photographs of the plates and the plate jackets. Contains an overall plate quality flag.
exposuresContains a list of all exposures and their characteristics as derived from the logbooks
catalog Contains transcriptions of the plate stacks card catalog. This data is being replaced by more detailed data from the logbooks themselves.
logbook Contains transcriptions of logbook data
lograngesContains the ranges of plate numbers in each logbook volume. This table is used in the verification of logbook transcriptions.
platerenameContains a table of renamed plates (deprecated)
scanPatternsContains a table of plate scan patterns executed by the digitizer.
scanLocations Contains a table of individual scan tile patterns for each scan pattern in the scanPatterns table
scans Contains a table of all plate scans executed by the digitizer
mosaics Contains a table of all mosaics generated from digitizer plate scans. This table contains World Coordinate Systems coefficients of each plate for the automated searches implemented by this website.
fithistory Contains a record of WCS fitting attempts (deprecated)
astromfithistory Contains the history of WCS fitting attempts after the transition to astrometry.net

Photometry Database

The database replaces a collection of tab-delimited ASCII Starbase Data Tables generated by the photometry pipeline. The intent of the photometry database is to provide rapid access to any lightcurve in the DASCH database. As currently designed, the photometry database contains the tables listed below. The primary spatial index into the database is a gsc_bin_index which divides the sky into 168,966,386 bins of height 1/64 degree in declination and approximately 1/64 degree in right ascension. This index is similar to the hierarchical triangle index developed for the SDSS, but optimized for rapid raster searches of the GSC2.3.2 star catalog. The illustration on the left shows how the tables are used to generate lightcurves.

photglobalContains global constants, control variables, and a time stamp.
photversionsContains version strings and identifiers in recognition of continuing development of the photometry pipeline. The versions are used to recognize and purge stale data from the other tables.
photseriesContains a copy of the series table index from the scanner database for more efficient MySQL queries
starsContains the star index based on either location or GSC2.3.2 reference ID and the GSC2.3.2 magnitude and color.
stars1Contains the star index based on either location or Kepler Input Catalog reference ID and the Kepler Input Catalog magnitude and color.
stars2Contains the star index based on either location or APASS Catalog reference ID and APASS magnitude and color.
photplatesContains a list of all plates processed by the photometry pipeline and global plate parameters, such as the plate scale, mosaic size, and Sextractor THRESHOLD level.
spatialbinContains derived parameters for the nine annular bins for each plate analyzed. These parameters include number of stars analyzed, limiting magnitude, upper limits, colorterm values, and bin rms.
localbinContains derived parameters for the 50x50 grid of local correction bins for each plate analyzed. These parameters include altitude in the sky; plate extinction; local calibration correction, number of stars, and correction rms value; and astrometry error measurements.
magnitudesContains values for each image on the plates. These values include GSC2.3.2 reference ID, plate coordinates, processing flags, magnitude, magnitude error, Heliocentric Julian date, and Sextractor shape parameters. This table is too large for efficient processing by MySQL and now consists of a series of binary files indexed by the gsc_bin_index.
starsummaryContains lightcurve statistics such as the number of points, DASCH magnitude and rms, clipped DASCH magnitude and rms, year range, and magnitude ranges. These statistics provide the basis for a search for interesting variable stars.
starsummary1Contains statistics of stars in the stars1 table processed with the Kepler Input Catalog instead of the GSC2.3.2 catalog
starsummary2Contains statistics of stars in the stars1 table processed with the APASS catalog instead of the GSC2.3.2 catalog
calibrationContains the relationship between SExtractor instrumental magnitude and GSC2.3.2 catalog magnitude for each plate and annular bin and the estimated RMS error for this relationship.
calibration1Contains the relationship between SExtractor instrumental magnitude and Kepler Input Catalog magnitude for each plate and annular bin and the estimated RMS error for this relationship.
calibration2Contains the relationship between SExtractor instrumental magnitude and APASS Catalog magnitude for each plate and annular bin and the estimated RMS error for this relationship.

Auxscanner Database

The auxscanner database contains tables which do not require periodic backup either because they are generated from text files or from other database tables.

loglinks Contains a linked list of all logbook page photographs for use by the logbook browser on this website.
logindexnew Contains the logbook volume and page number for all plates. Used by the logbook browser on this website.
coverage Contains a list of all plates indexed by one degree square regions of the sky. Used by the lightcurve generator.
disks Contains a list of all disks and raid arrays used by the DASCH project.
variables Contains the list of database variables listed in the Database Variables table below. Used for generation of VOTables

Database Variables

The remainder of this page contains reference tables useful mostly to the DASCH pipeline developers and to researchers who have been provided with DASCH photometry results.

Table of Variables Used in the Photometry Database
variableNamedatatypeunitvariableDescription
A2FLAGSintAdditional photometry warning flags
adjacentburstdipintctA measure of the number of adjacent nburst3/4 and ndip3/4 points in a lightcurve
adjacentburstdip2intctA measure of the number of >5 adjacent nburst3/4 and ndip3/4 points in a lightcurve
adjacentburstdip3intctA measure of the number of >7 adjacent points 2-sigma above or below the median value of a lightcurve
AFLAGSintPhotometry warning flags
AFLAGSBitscharListing of bits set in the photometry warning flags
AFLAGS_1intPhotometry warning flags
AFLAGS_2intPhotometry warning flags
aLengthdoublepixImage long semi-axis in pixels
aLength_1doublepixImage long semi-axis in pixels
aLength_2doublepixImage long semi-axis in pixels
alternateDatecharY-M-D,h:m:sAlternate dark, flatfield, or linearity test for failed test
altitudedoubledegHeight of the object above the horizon in degrees
ANALYSIS_THRESHOLDdoubleDetection threshold above background. See sextractor manual.
aperturedoublemTelescope aperture in meters. Some series, notably mb, contain plates from serveral telescopes.
arraysizeintctLength of a variable character string
aveADUintctAverage ADU level for all of the tile
aveLengthRatiodoublepixAverage aLength/bLength SExtractor images in a candidate scratch chain
aveNeighborCtdoublectAverage number of neighbering matched SExtractor images in a candidate scratch chain
aveTileSaturationintctAverage number of saturated pixels per tile
B2FLAGSintAdditional photometry processing flags
BACKGROUNDdoublectBackground at centroid position
BACKGROUND_1doublectBackground at centroid position
BACKGROUND_2doublectBackground at centroid position
background_ratiodoublect(Image filtered background background)/(filtered background RMS)
BFLAGSintPhotometry processing flags
BFLAGSBitscharListing of bits set in the photometry processing flags
BFLAGS_1intPhotometry processing flags
BFLAGS_2intPhotometry processing flags
binningintBinning (1x1 or 16x16) of the mosaic used for WCS fitting
bin_countintctNumber of images in a spatial bin.
BlendedmagdoublemagFor case B and BD objects, the effective magnitude of all of the GSC2.3.2 objects within the blend.
Blendedmag_1doublemagFor case B and BD objects, the effective magnitude of all of the GSC2.3.2 objects within the blend.
Blendedmag_2doublemagFor case B and BD objects, the effective magnitude of all of the GSC2.3.2 objects within the blend.
bLengthdoublepixImage short semi-axis in pixels
bLength_1doublepixImage short semi-axis in pixels
bLength_2doublepixImage short semi-axis in pixels
bmag0doublemagedge of magnitude bin for magnitude-dependent calibration
borderintpixCrop border in pixels. WCStools 'imwcs' input parameter.
bottomMarginintpixBottom margin in pixels
boundenumbitBound 'b' or unbound 'u' logbooks
bright_magcor_errordoublemagmagcal_local_error for brightest two magnitudes
bright_magcor_localdoublemagmagcor_local for brightest two magnitudes
bright_npoints_localintctnpoints_local for brightest two magnitudes
BTmagdoublemagGSC2.3.2 Tycho2 blue magnitude
BTminusVTmagdoublemagTycho2 BT-VT color
calcTimeTypecharCalculated Date Type: (EST, LST, UT, SAST, ...)
calibrationDatecharY-M-D,h:m:sDate of dark, flatfield, or linearity test
calibrationStatussetcalibration test status: acquired, processed, failed, or deleted
calibrationTypesetcalibration test type: dark, flat, or linearity
CAL_FLAGintDeprecated, now part of BFLAGS
cal_localintbitIf 1, local calibration was used; otherwise 0; becomes part of BFLAGS
capacityintbyte9Disk capacity in gigabytes
catalogenumFitting catalog 'imwsky2k' or 'imwty2'. WCStools 'imwcs' input parameter.
catalogDistDifferentMagintctHistogram of the distances of DASCH objects from nearby catalog objects differing by more than 2 magnitudes
catalogDistSimilarMagintctHistogram of the distances of DASCH objects from nearby catalog objects within 2 magnitudes
catalogDistTotalintctHistogram of the distances of DASCH objects from nearby catalog objects
catalogmagdoublemagMagnitude from variable star or galaxy catalog. Miscellaneous filters.
catalognamecharThe GSC2.3.2 ID.
catalogNumberintctCalibration Catalog 0 = gsc2.3.2, 1 = KIC, 2 = APASS, 3 = experimental
catdecdoubledegCatalog J2000 Declination in degrees
catradoubledegCatalog J2000 Right Ascension in degrees
cd1_1doubledeg/pixChange in RA---TAN along X axis
cd1_2doubledeg/pixChange in RA---TAN along Y axis
cd2_1doubledeg/pixChange in DEC--TAN along X axis
cd2_2doubledeg/pixChange in DEC--TAN anong Y axis
cdecdoubledegSearch center or plate center Declination in degrees
centerintctAverage position: center of the magnet for the plate washer
centerDriftintpixCenter drift of solution in pixels
centerSourceenumSource of J2000 RA and DEC 'Catalog', 'Logbook','imWCS' or 'WCS'
chnintKepler satellite CCD channel
classintGSC2.3.2 object type 0 = star 3 = non-star; also synonym for plateClass
classDescriptioncharDescription of plate class
class_1intGSC2.3.2 object type 0 = star 3 = non-star; also synonym for plateClass
class_2intGSC2.3.2 object type 0 = star 3 = non-star; also synonym for plateClass
clip_median_localdoublemagMedian DASCH magnitude of clipped dataset
clip_ngoodintctClipped number of points to compute the clipped median DASCH magnitude
clip_rms_localdoublemagDASCH magnitude RMS of the clipped dataset
coldoubleKepler satellite CCD column
colordoublemagmagj-magf
colorflagenumColor correction flag 'linear', 'metropolis' or 'copy'
colortermdoubleColor correction term, multiply by color and subtract to convert locally calibrated magnitudes to catalog color system
color_1doublemagmagj-magf
color_2doublemagmagj-magf
commentscharDisk event comments
convolutionAreaintpix2Correlation area
convolutionRadiusintpixCorrelation radius
correlationLimitintpixWCS fitting correlation limit in pixels. WCStools 'imwcs' input parameter.
countintctCount of good stars in the summary file or count of mosaics for dxmedian and dymedian
count2intctCount of images in a declination band above a particular galactic latitude
count3intctCount of images in a declination band
count_limitdoublectMinimum significant correlation bin count
count_meddoublectMedian correlation bin count
count_rmsdoublectRMS of the correlation bin count
coverage_bin_indexintCoverage bin index (approximately 1 square degree of sky)
cradoubledegSearch center or plate center Right Ascension in degrees
crpix1doublepixX-axis reference pixel
crpix2doublepixY-axis reference pixel
crval1doubledegX-axis coordinate value
crval2doubledegY-axis coordinate type
ctype1charX-axis coordinate type
ctype2charY-axis coordinate type
currentVersionintLatest version of the photometry database
damonBlueRmsdoublemagRMS of good lightcurve magnitudes in dnb and dsb plates
Damon_factordoublemagdifference in clipped DASCH median magnitude for the dnb and dsb series and all non-Damon plates
daschProcessorintctserver on which the photometry pipeline has been executed for this plate.
datatypeenumVariable datatype ('char', 'double', 'int', 'short', 'enum', 'set' or 'long')
datecharY-M-D,h:m:sGeocentric exposure date (See ExposureDate for Date)
Date_1doubleJDGeocentric Julian date of plate or Heliocentric Julian date of an image
Date_2doubleJDGeocentric Julian date of plate or Heliocentric Julian date of an image
ddecdoublearcsec(image - catalog) declination in arcseconds, catalog corrected for proper motion.
dDeclinationdoubledegDecimal J2000 declination in degrees
ddecMediandoublearcsecMedian declination error in arcsec per smoothing bin (tnx fitting quality in filterblended)
ddecMedian2doublearcsecMedian declination error in arcsec per smoothing bin (final tnx adjustment in recover_points)
ddecRMSdoublearcsecRMS declination error in arcsec per smoothing bin (tnx fitting quality in filterblended)
ddecRMS2doublearcsecRMS declination error in arcsec per smoothing bin (final tnx adjustment in recover_points)
ddec_1doublearcsec(image - catalog) declination in arcseconds, catalog corrected for proper motion.
ddec_2doublearcsec(image - catalog) declination in arcseconds, catalog corrected for proper motion.
decdoubledegDeclination in degrees
decimalPlacesintVariable field precision
declinationdoubledegSynonym for dec to avoid MySQL keyword
declinationStringchardegSynonym for dec to avoid MySQL keyword
decPixelsdoublepixOffset in declination pixels from the previous exposure
DecPMdoublemas/yrDeclination proper motion in mas/yr
DecPMSigmadoublemas/yrDeclination proper motion error in mas/yr
decrmsdoubledegStandard deviation of lightcurve dec
DecSigmaPMdoublemas/yrDeclination proper motion error in mas/yr
dec_1doubledegImage declination from sextractor
dec_1_1doubledegImage declination from sextractor
dec_1_2doubledegImage declination from sextractor
dec_2doubledegCatalog star declination, precessed to current epoch
dec_2_1doubledegCatalog star declination, precessed to current epoch
dec_2_2doubledegCatalog star declination, precessed to current epoch
Dec_TCdoubledegWeighted Declination in degrees of the lightcurve points in the selected transient window. Synonym for peakDec
defectFlagintbitSExtractor image is a plate defect
degDraddoubledegdifference between GSC2.3.2 and Kepler Input Catalog positions in degrees
descriptioncharDescription of pattern, or telescope
diskLocationintDisk raid array number containing the scan tiles or mosaic
diskStatusenumDisk status 'InService', 'Spare', 'Failed' or 'Returned'
dixintx bin index in calculation of dxmedian and dymedian
diyinty bin index in calculation of dxmedian and dymedian
dmagdoublemagdifference in magnitude
dmagcatalogdoublemagThe differences between catalog magnitude and median magnitude in the plates
dmag_isodoublemagdifference between the lowess-fitted magnitude and catalog magnitude
dmag_localdoublemagdifference between locally corrected calibrated isophotal magnitude and the catalog magnitude
dnxintctNumber of horizontal bins in calculation of dxmedian and dymedian
dnyintctNumber of vertical bins in calculation of dxmedian and dymedian
dradoublearcsec(image - catalog) right ascension in arcseconds, catalog corrected for proper motion
draddoublearcsecdifference between catalog and image position in arcseconds
dradAveragedoublearcsecThe average astrometric mismatch error for a local bin in arcseconds.
dradBdoublearcsecRMS uncertainty in arcsec for good points, defects, low altitude, uncertain date, and second quality plates
dradRMS2doublearcsecRMS positional error in arcsec per smoothing bin (final tnx adjustment in recover_points)
dradRMS2_1doublearcsecRMS positional error in arcsec per smoothing bin (final tnx adjustment in recover_points)
dradRMS2_2doublearcsecRMS positional error in arcsec per smoothing bin (final tnx adjustment in recover_points)
drad_1doublearcsecdifference between catalog and image position in arcseconds
drad_2doublearcsecdifference between catalog and image position in arcseconds
drad_bin_countintctNumber of stars used to compute draMedian and ddecMedian (tnx fitting quality in filterblended)
drad_bin_count2intctNumber of stars used to compute draMedian and ddecMedian (final tnx adjustment in recover_points)
drad_bin_sizeintctNumber of smoothing bins used to compute draMedian and ddecMedian (tnx fitting quality in filterblended)
drad_bin_size2intctNumber of smoothing bins used to compute draMedian and ddecMedian (final tnx adjustment in recover_points)
drad_reject_countintctStars rejected for high drad (tnx fitting quality in filterblended)
drad_reject_count2intctStars rejected for high drad (final tnx adjustment in recover_points)
draMediandoublearcsecMedian Right Ascension error in arcsec per smoothing bin (tnx fitting quality in filterblended)
draMedian2doublearcsecMedian Right Ascension error in arcsec per smoothing bin (final tnx adjustment in recover_points)
draRMSdoublearcsecRMS Right Ascension error in arcsec per smoothing bin (tnx fitting quality in filterblended)
draRMS2doublearcsecRMS Right Ascension error in arcsec per smoothing bin (final tnx adjustment in recover_points)
dra_1doublearcsec(image - catalog) right ascension in arcseconds, catalog corrected for proper motion
dra_2doublearcsec(image - catalog) right ascension in arcseconds, catalog corrected for proper motion
dRightAscensiondoubledegJ2000 Right ascension in degrees
dxmediandoublepixmedian x-axis angular difference in pixels between TNX and TAN fits.
dxrmsdoublepixRMS of the x-axis angular difference in pixels between TNX and TAN fits.
dxvaldoublepixx-axis angular difference in pixels between TNX and TAN fits
dymediandoublepixmedian y-axis angular difference in pixels between TNX and TAN fits.
dyrmsdoublepixRMS of the y-axis angular difference in pixels between TNX and TAN fits.
dyvaldoublepixy-axis angular difference in pixels between TNX and TAN fits.
eixintx position of an extinction bin (0-49)
eiyintx position of an extinction bin (0-49)
elevationdoublemElevation above sea level in meters
ELLIPTICITYdoubleSee sextractor manual. (1 - B_IMAGE/A_IMAGE)
ELLIPTICITY_1doubleSee sextractor manual. (1 - B_IMAGE/A_IMAGE)
ELLIPTICITY_2doubleSee sextractor manual. (1 - B_IMAGE/A_IMAGE)
enableFindWCSenumbitSet to 'no' to abort FindWCS or AstronmetryWCS execution; otherwise 'yes'
enxintNumber of horizontal bins in an extinction table
enyintNumber of vertical bins in an extinction table
epochdoubleyrDatabase epoch
equinoxdoubleyrDatabase equinox
ERRA_IMAGEdoublepixRMS position error along major axis. See sextractor manual
ERRA_WORLDdoubledegWorld RMS position error along major axis. See sextractor manual.
ERRB_IMAGEdoublepixRMS position error along minor axis. See sextractor manual.
ERRB_WORLDdoubledegWorld RMS position error along minor axis. See sextractor manual.
errorcolordoubleRMS Error in the color correction term
errorCountintctNumber of plates in error
errorTypesetLogbook error type
error_bar_factordoubleError bar factor: min(1.0,the median RMS of the lightcurve divided by the median zero-based RMS of the local calibration RMS of all of the individual points in the lightcurve)
erroutdoublemagLocal correction error
ERRTHETA_IMAGEdoubledegRMS position error along minor axis. See sextractor manual.
ERRTHETA_J2000doubledegJ2000 error ellipse pos. angle (east of north)
ERRTHETA_WORLDdoubledegWorld RMS position error along major axis. See sextractor manual.
EstDecPMdoublemas/yrEstimated declination proper motion in mas/yr
EstDecPMRMSdoublemas/yrStandard Deviation of the estimated declination proper motion in mas/yr
EstRaPMdoublemas/yrEstimated Right Ascension proper motion in mas/yr
EstRaPMRMSdoublemas/yrRMS of the estimated Right Ascension proper motion in mas/yr
eventDatecharY-M-D,h:m:sDisk event date
expansionRadiusdoublepixaverage background calculation bin radius
exposurecharminLogbook exposure time, normally in minutes but may be qualified by other units
ExposureDatedoubleJDGeocentric Julian date of plate or Heliocentric Julian date of an image
exposureNumberintctThe zero-based exposure number listed in the logbooks, or -1 if WCS fitting finds more solutions than logbook entries.
exposuresintctNumber of exposures fitted for this plate
extinctiondoublemagExtinction estimate for an image.
extinction_1doublemagExtinction estimate for an image.
extinction_2doublemagExtinction estimate for an image.
fatalErrorintterminating condition of the photometry pipeline for this plate.
fatalSolutionintctterminating solutionNumber of the photometry pipeline for this plate
fileExistsint1 if the drad file associated with a plate exists; 0 otherwise
fileObsoleteint1 if the drad file associated with a plate is obsolete; 0 otherwise
fileOffsetintByte position offset of the gsc bin into a photometry database file
filingReleaseFieldintctFiling location release field (DR1-DR12)
FILTERED_BACKGROUNDdoublectHigh-pass filtered background at centroid position
firstPlateintInitial plate number in the range
fittedPlateScaledoublearcsec/m-3Average plate scale from available WCS fits in arc seconds per mm
FitWCSsetWCS fitting and pipeline status
flagdoublePlotting flag.
flaggridintcalibration table entry type 0 = too bright, 1 = valid, -1 = too dim
FLAGSintPhotometry flag defined by sextractor. See sextractor manual.
flag_MAG_ISOintbitSExtractor image is brighter than the estimated limiting MAG_ISO
flatLinearityJDdoubleJDJulian Date of the last flatfield prior to the scan
FLUXERR_AUTOdoublectRMS error for AUTO flux. See sextractor manual.
FLUXERR_ISOdoublectRMS error for isophotal flux. See sextractor manual.
FLUX_AUTOdoublectFlux within a Kron-like elliptical aperture. See sextractor manual.
FLUX_ISOdoublectIsophotal flux. See sextractor manual.
FLUX_ISO_1doublectIsophotal flux. See sextractor manual.
FLUX_ISO_2doublectIsophotal flux. See sextractor manual.
FLUX_MAXdoublectPeak flux above background. See sextractor manual.
FLUX_MAX_1doublectPeak flux above background. See sextractor manual.
FLUX_MAX_2doublectPeak flux above background. See sextractor manual.
focusdoublemmFocus position in mm
fractiondoubleFractional extra stars used for WCS fitting. WCStools 'imwcs' input parameter.
FWHM_IMAGEdoublepixFWHM assuming a gaussian core. See sextractor manual.
FWHM_IMAGE_1doublepixFWHM assuming a gaussian core. See sextractor manual.
FWHM_IMAGE_2doublepixFWHM assuming a gaussian core. See sextractor manual.
FWHM_WORLDdoubledegFWHM assuming a gaussian core. See sextractor manual.
FWHM_WORLD_1doubledegFWHM assuming a gaussian core. See sextractor manual.
FWHM_WORLD_2doubledegFWHM assuming a gaussian core. See sextractor manual.
galacticbinintctGalactic Bin Sequence for Scanning
galaxyflagintctType of record in the limiting magnitude or nearby object databases
galaxytypecharType of variable (in GCVS) or origin of galaxy reference
galaxyversionintctVersion format of the nearby objects table
GclassintGSC2.3.2 object type 0 = star 3 = non-star; also synonym
GcolordoublemagGSC magj-magf
GdecdoubledegGSC Declination in degrees
GDecPMdoublemas/yrGSC Declination proper motion in mas/yr
geoJulianDatedoubleJDGeocentric Julian date of plate
gmagdoublemagSDSS g magnitude
GMAGFlagintGSC2.3.2 magnitude origin
gminusrmagdoublemagsdss g-r color
goodBinsintctnumber of local smoothing bins without any error flags set
goodDradBinsintctnumber of local smoothing bins with acceptable positional errors
goodLocalBinsintctnumber of local smoothing bins with local smoothing correction values
goodMedianBinsintctnumber of local smoothing bins where the median Stdmag is less than the ((median limiting_mag) + 0.5) magnitudes
goodZoutBinsintctnumber of local smoothing bins with acceptable local smoothing corrections
GradoubledegGSC Right Ascension in degrees
GRaPMdoublemas/yrGSC Right Ascension proper motion in mas/yr
GREFcharThe GSC2.3.2 ID.
griderrdoublemaglowess fit error in the calibration table
groupintThe number of each group of unmatched catalog images associated with a single source
groupCountintctThe count of unmatched catalog images associated with a single source
gsc2_idcharGSC2 star ID, becomes REF in subsequent tables
GSCBlendFlagintbitIf 1, the unmatched image is too close to a bright GSC2.3.2 catalog star; 0 otherwise
gscclassintGSC2.3.2 star class 0 = star; 3 = non-star
gsccolordoublemagGSC (JpgMag - FpgMAG) also expressed as ( magj-magf)
gsc_bin_indexintA spatial index of approximately 1/4096 degree used to sort images in the input star catalog and the photometry database.
gsc_bin_index_1intA spatial index of approximately 1/4096 degree used to sort images in the input star catalog and the photometry database.
gsc_bin_index_2intA spatial index of approximately 1/4096 degree used to sort images in the input star catalog and the photometry database.
GStdmagdoublemagGSC2.3.2 GSC magj magnitude
GVFlagintbitIf nonzero, the GSC catalog star is has an uncertin magnitude.
heightJPEGintpixLength of the y axis of the CameraPC image
hJDdoubleJDHeliocentric Julian Day
hourAnglecharHH:MM:SSLogbook hour angle
hoursdoublectUnrelated to astronomy
imagbintctmagnitude index for magnitude-dependent calibration
iMAG_ISOintStandard sextractor MAG_ISO bin index. There are 220 bins between MAG_ISO = -22 and MAG_ISO = 0.0
indexintgsc bin offset into a photometry database file. Add to the base index to get gsc_bin_index
inventoryenumbitIf 'yes' disk found during inventory; otherwise 'no'
ISO0intpix2Isophotal area at level 0. See sextractor manual.
ISO0_1intpix2Isophotal area at level 0. See sextractor manual.
ISO0_2intpix2Isophotal area at level 0. See sextractor manual.
ISO1intpix2Isophotal area at level 1. See sextractor manual.
ISO1_1intpix2Isophotal area at level 1. See sextractor manual.
ISO1_2intpix2Isophotal area at level 1. See sextractor manual.
ISO2intpix2Isophotal area at level 2. See sextractor manual.
ISO2_1intpix2Isophotal area at level 2. See sextractor manual.
ISO2_2intpix2Isophotal area at level 2. See sextractor manual.
ISO3intpix2Isophotal area at level 3. See sextractor manual.
ISO3_1intpix2Isophotal area at level 3. See sextractor manual.
ISO3_2intpix2Isophotal area at level 3. See sextractor manual.
ISO4intpix2Isophotal area at level 4. See sextractor manual.
ISO4_1intpix2Isophotal area at level 4. See sextractor manual.
ISO4_2intpix2Isophotal area at level 4. See sextractor manual.
ISO5intpix2Isophotal area at level 5. See sextractor manual.
ISO5_1intpix2Isophotal area at level 5. See sextractor manual.
ISO5_2intpix2Isophotal area at level 5. See sextractor manual.
ISO6intpix2Isophotal area at level 6. See sextractor manual.
ISO6_1intpix2Isophotal area at level 6. See sextractor manual.
ISO6_2intpix2Isophotal area at level 6. See sextractor manual.
ISO7intpix2Isophotal area at level 7. See sextractor manual.
ISO7_1intpix2Isophotal area at level 7. See sextractor manual.
ISO7_2intpix2Isophotal area at level 7. See sextractor manual.
ISOAREA_IMAGEdoublepix2Isophotal area above Analysis threshold. See sextractor manual.
ISOAREA_WORLDdoubledeg2Isophotal image area in square degrees. See sextractor manual.
ISOAREA_WORLD_1doubledeg2Isophotal image area in square degrees. See sextractor manual.
ISOAREA_WORLD_2doubledeg2Isophotal image area in square degrees. See sextractor manual.
isogriddoublemagisophotal magnitude in calibration table
ixintx position of a local calibration bin (0-49)
ixbintctx index for magnitude-dependent calibration
iyinty position of a local calibration bin (0-49)
iybintcty index for magnitude-dependent calibration
jacketJPEGenumbitIf 'yes' a plate jacket JPEG image is available, otherwise 'no'
julianDatecharJDJulian Date from logbook
KclassintKepler object type 0 = star 3 = non-star; also synonym
KcolordoublemagKepler magj-magf
KdecdoubledegKepler Declination in degrees
KDecPMdoublemas/yrKepler Declination proper motion in mas/yr
keepaliveenumbitSet to 'no' when aborting a photometry database update, otherwise 'yes'
keplerFieldenumbitIf 'yes', object is on a Kepler CCD chip. Otherwise 'no'
kmagbintctNumber of magnitude bins for magnitude-dependent calibration
KMAGFlagintKepler magnitude origin
KradoubledegKepler Right Ascension in degrees
KRaPMdoublemas/yrKepler Right Ascension proper motion in mas/yr
KREFcharThe Kepler ID.
KRON_RADIUSdoubleKron apertures in units of A or B. See sextractor manual.
KRON_RADIUS_1doubleKron apertures in units of A or B. See sextractor manual.
KRON_RADIUS_2doubleKron apertures in units of A or B. See sextractor manual.
KStdmagdoublemagKepler magj magnitude
KVFlagintbitIf nonzero, the Kepler catalog star has an uncertain magnitude.
kxbintctNumber of x bins for magnitude-dependent calibration
kybintctNumber of y bins for magnitude-dependent calibration
lastPlateintLast plate number in the range.
latdoubledegCatalog star galactic latitude
latitudedoubledegObservatory latitude in degrees
leftMarginintpixLeft margin in pixels
lightcurveCountintctNumber of lightcurves on this plate
lightcurverms1doublemag5-sigma clipped RMS of good lightcurve points
lightcurverms2doublemag5-sigma clipped RMS of good lightcurve points after detrending (smooth(x,y,0.4,'lowess'))
lightcurverms3doublemag5-sigma clipped RMS of good lightcurve points after detrending (smooth(y,0.8,'lowess'))
lightcurverms4doublemag5-sigma clipped RMS of good lightcurve points after detrending (smooth(y,10,'sgolay'))
lightcurverms5doublemag5-sigma clipped rms of good lightcurve points after detrending (smooth(y,15,'loess'))
limiting_isodoublemagInstrumental isophotal magnitude which corresponds to the lowess limiting magnitude
limiting_magdoublemaglowess limiting magnitude
limiting_mag_localdoublemagLocally corrected limiting magnitude
limiting_mag_local_1doublemagLocally corrected limiting magnitude
limiting_mag_local_2doublemagLocally corrected limiting magnitude
lineintLine number of the logbook transcription
listNamecharFilename containing a list of plates
local_binshortLocal calibration bin number (ix + (nx * iy))
local_bin_1shortLocal calibration bin number (ix + (nx * iy))
local_bin_2shortLocal calibration bin number (ix + (nx * iy))
local_bin_indexshortLocal calibration bin number (ix + (nx * iy))
locationIdintTelescope location index
logPagecharLogbook volume and page
logRemarkenumbitIf 'Y' a logbook remark is present, otherwise 'N'. Deprecated.
logTimeTypecharDate type given in the logbook ('EST', 'LST', 'UT', 'SASE' ...)
londoubledegCatalog star galactic longitude
M0doublemagmagnitude range for magnitude-dependent calibration
magcal_isodoublemagmagnitude estimate from lowess fitting
magcal_iso_1doublemagmagnitude estimate from lowess fitting
magcal_iso_2doublemagmagnitude estimate from lowess fitting
magcal_iso_errordoublemag- plate overall rms error between the lowess and catalog magnitude.
magcal_iso_rmsdoublemagerror in the lowess fitting algorithm
magcal_iso_rms_1doublemagerror in the lowess fitting algorithm
magcal_iso_rms_2doublemagerror in the lowess fitting algorithm
magcal_localdoublemaglocally corrected magnitude
magcal_local_1doublemaglocally corrected magnitude
magcal_local_2doublemaglocally corrected magnitude
magcal_local_errordoublemag(ERROUT in contour_plot_clip_smooth_correct2.f) rms of the needed median magnitude correction
magcal_local_error_1doublemag(ERROUT in contour_plot_clip_smooth_correct2.f) rms of the needed median magnitude correction
magcal_local_error_2doublemag(ERROUT in contour_plot_clip_smooth_correct2.f) rms of the needed median magnitude correction
magcal_local_rmsdoublemagError of the locally corrected magnitude.
magcal_local_rms_1doublemagError of the locally corrected magnitude.
magcal_local_rms_2doublemagError of the locally corrected magnitude.
magcal_magdepdoublemagmagnitude-dependent corrected magnitude
magcal_magdep_1doublemagmagnitude-dependent corrected magnitude
magcal_magdep_2doublemagmagnitude-dependent corrected magnitude
magcal_magdep_rmsdoublemagError of the magnitude-dependent correction
magcal_magdep_rms_1doublemagError of the magnitude-dependent correction
magcal_magdep_rms_2doublemagError of the magnitude-dependent correction
magcor_localdoublemag(ZOUT in contour_plot_clip_smooth_correct2.f) median magnitude correction needed in a given plate ragion
magcor_local_rangedoublemagDeprecated. Range in magcor_local within a smoothing bin.
magcor_rmsbrightdoublemagDeprecated. magcor_local_rms of the 30 brightest stars in a local smoothing bin.
magcor_rmsdimdoublemagDeprecated. magcor_local_rms of the 30 dimmest stars in a local smoothing bin.
magdep_binintMagnitude-dependent calibration bin number (ixb + (kxb*iyb) * (kxb*kyb*imagb))
magdep_bin_1intMagnitude-dependent calibration bin number (ixb + (kxb*iyb) * (kxb*kyb*imagb))
magdep_bin_2intMagnitude-dependent calibration bin number (ixb + (kxb*iyb) * (kxb*kyb*imagb))
magdep_bin_edgedoublemagDimmest GSC2.3.2 magj minimum magnitude in a magnitude correction bin
magdep_bin_magcordoublemagmedian magnitude magnitude-dependent correction
magdep_bin_mediandoublemagMedian GSC2.3.2 magj median magnitude in a magnitude correction bin
magdep_bin_qualitydoublemagMagnitude dependent bin quality measure (magdep_bin_magcor * sqrt(nstar_magdep))/magcal_magdep_rms
magdep_bin_sizeintctBin expansion factor for magnitude-dependent correction
magdiffdoublemagMagnitude difference between GSC JpgMag and SDSS gmag
MAGERR_APERdoublemagRMS error vector for fixed aperture mag.
MAGERR_AUTOdoublemagRMS error for AUTO magnitude
MAGERR_ISOdoublemagRMS error for isophotal magnitude
magfdoublemagGSC2 red magnitude.In subsequent tables color = magj - magf
MAGFlagintGSC2.3.2 magnitude origin
MAGFlag_1intGSC2.3.2 magnitude origin
MAGFlag_2intGSC2.3.2 magnitude origin
maggriddoublemagbest lowess fit magnitude in calibration table
magjdoublemagGSC2 blue magnitude, becomes Stdmag in subsequent tables
magnitudeFileenumbitIf 'yes' magnitudes are in a file, if 'no' magnitudes are in a MySQL table.
magvsdeccorrdoublemagCorrelation coef. between lightcurve magnitude and dec
magvslimitingcorrdoublemagcorrelation coef. between lightcurve magnitude and limiting magnitude
magvsracorrdoublemagCorrelation coef. between lightcurve magnitude and ra
MAG_APERdoublemagFixed aperture magnitude vector. See sextractor manual.
MAG_APER_1doublemagFixed aperture magnitude vector. See sextractor manual.
MAG_APER_2doublemagFixed aperture magnitude vector. See sextractor manual.
MAG_AUTOdoublemagKron-like elliptical aperture magnitude. See sextractor manual.
MAG_AUTO_1doublemagKron-like elliptical aperture magnitude. See sextractor manual.
MAG_AUTO_2doublemagKron-like elliptical aperture magnitude. See sextractor manual.
MAG_ISOdoublemagSee sextractor manual. isophotal magnitude
MAG_ISO_1doublemagSee sextractor manual. isophotal magnitude
MAG_ISO_2doublemagSee sextractor manual. isophotal magnitude
MAG_ISO_meddoublemagSee sextractor manual. median isophotal magnitude
MAG_ISO_rmsdoublemagSee sextractor manual. rms of the isophotal magnitude
Malmquist_factordoublemagclipped median DASCH magnitude of 20 deepest plates - clipped median DASCH magnitude of 20 shallowest plates using good points
Malmquist_factorBdoublemagclipped median DASCH magnitude of 20 deepest plates - clipped median DASCH magnitude of 20 shallowest plates using good points, defects, low altitude, uncertain date, and second quality plates
maskAreaintpix2Area of the mask
maskAreaRatiodoublectMedian correlation bin count
maskCenterDistancedoublectMedian correlation bin count
maskCenterFlagintctNonzero if the mask covers the plate center
maskCountintctNumber of masked regions in the plate
maskIndexintctIndex (one-based) of this mask
maskNumberintLast plate number in the mask pseudo-series
maskXMaxintpixMaximum x value of the mask
maskXMinintpixMinimum x value of the mask
maskYMaxintpixMaximum Y value of the mask
maskYMinintpixMinimum y value of the mask
matchCountintctNumber of catalog matches on this plate
matchRatiodoubleFraction of images on this plate which have been matched to a catalog
MATCH_NUMBERintThe sextractor image NUMBER that a Pickering Wedge ghost image is associated with
maxBinCountintctMaximum correlation bin count
maxBinSNRdoublectmaxBinCount divided by count_rms
maxDist1doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 1
maxDist2doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 2
maxDist3doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 3
maxDist4doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 4
maxDist5doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 5
maxDist6doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 6
maxDist7doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 7
maxDist8doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 8
maxDist9doublepixMaximum difference in pixels between TNX and TAN fits for spatial_bin 9
maxIxintctHighest x bin (along width) of the emulsion area
maxIyintctHighest y bin (along height) of the emulsion area
maxmagintmagMaximum bin magnitude in the summary file.
maxmagdiffdoublemagmaximum magnitude difference between spatial bins for a given MAG_ISO
maxSpatialBinsintMaximum number of annular bins, normally 9
maxTileSaturationintctMaximum number of saturated pixels in any tile
max_bright_isodoublemagIsophotal magnitude corresponding to the brightest reliable magnitude in a spatial bin.
max_bright_magdoublemagBrightest reliable lowess magnitude in a spatial bin.
max_draddoublearcsecMaximum difference between catalog and image position in arcseconds for good points
max_dradBdoublearcsecMaximum difference between catalog and image position in arcseconds for good points, defects, low altitude, uncertain date, and second quality plates
max_localdoublemagDimmest locally corrected magnitude for a lightcurve
max_local2doublemagSecond dimmest locally correccted magnitude for a lightcurve
measurementCountintctNumber of photometry measurements on this plate
medDamonBluedoublemagMedian of good lightcurve magnitudes in dnb and dsb plates
mediandoublemagMedian RMS in the summary file
medianStdmagdoublemagThe median magnitude of GSC2.3.2 images rejected by matchstars and filterblended because there are not enough sextractor images to match them with
median_draddoublearcsecMedian astrometric error in arcseconds within a spatial bin.
median_isodoublemagMedian lowess magnitude in a lightcurve
median_localdoublemagMedian locally corrected magnitude in a lightcurve
medNonDamonBluedoublemagMedian of good lightcuve magnitudes excluding dnb and dsb plates
memberCountintctNumber of SExtractor images in a candidate scratch chain
milesdoublectUnrelated to astronomy
minIxintctLowest x bin (along width) of the emulsion area
minIyintctLowest y bin (along height) of the emulsion area
minmagintmagMinimum bin magnitude in the summary file.
minVersionIdintMinimum valid versionId
min_localdoublemagBrightest locally corrected magnitude in a lightcurve
min_local2doublemagSecond brightest locally corrected magnitude in a lightcurve
missingFlagintctIf 1, the plate is marked as missing in the stacks database
modelcharDisk model from manufacturer
mosaiccharSynonym for plate or Plate
mosaicBinningsetBinning of available mosaics
mosaicCommentcharMosaic comment
mosaicDatecharY-M-D,h:m:sDate mosaic was generated
mosaicHeightintpixMosaic height in pixels
mosaicNumberintctMosaic number for this plate
mosaicWidthintpixWidth of this mosaic
multipleFlagintctIf 1, the plate has multiple exposures
n1intctTotal points read by annular9.m for a lowess fit attempt.
n2intctActual number of points used by annular9.m for a lowess fit attempt.
namecharName of the observing station
naxis1intpixLength of the x axis of the image in pixels (width)
naxis2intpixLength of the y axis of the image in pixels (height)
nblendintctNumber of blended lightcurve points
nburstintctNumber of good lightcurve points 0.8 mag above the median value
nburst2intctNumber of good lightcurve points 0.5 mag above the median value
nburst3intctNumber of good lightcurve points 0.4 mag above the median value
nburst4intctNumber of good lightcurve points 3-sigma above the median value
nDamonBlueintctNumber f good lightcurve points in dnb and dsb plates
ndev2intctNumber of good lightcurve points 2-sigma from the median value
ndev3intctNumber of good lightcurve points 3-sigma from the median value
ndipintctNumber of good lightcurve points 0.8 mag below the median value
ndip2intctNumber of good lightcurve points 0.5 mag below the median value
ndip3intctNumber of good lightcurve points 0.4 mag below the median value
ndip4intctNumber of good lightcurve points 3-sigma below the median value
nearbyObjectscharNearby object of interest @ distance in arcsec
nearbyREFflagintctIf 1, a nearby catalog star is within one half the smallest full width half maximum image size and dimmer than the catalog magnitude - 0.5 mag.
nearbyVSXcharNearby VSX object of interest @ distance in arcsec
nearestREFcharThe ID of a catalog star closest to an unmatched image.
nearestREFarcsecdoublearcsecThe distance in arcsec between an unmatched image and the closest catalog star
nextboundenumbitNext bound ('b') or unbound ('u') logbook in logbook browser linked list
nextpageintNext logbook page number in logbook linked list
nextseriescharNext logbook series in logbook linked list
nextvolumeintNext logbook volume in logbook linked list
ngoodintctNumber of good points in a lightcurve. (AFLAGS = 0 with ra and dec filtering)
ngoodBintctNumber lightcurve points with good points, defects, low altitude, uncertain date, and second quality plates.
nlocalintctNumber of good images in a local correction bin.
nmatchintctNumber of stars matched during WCS fitting. WCStools 'imwcs' result.
nNonDamonBlueintctNumber of good lightcurve points excluding dnb and dsb plates
nominalPlateScaledoublearcsec/m-3Nominal plate scale in arc seconds per mm
nonDamonBluermsdoublemagRMS of good lightcurve magnitudes excluding dnb and dsb plates
normadjacentburstdip2doublectNormalized adjacentburstdip2: Number of good lightcurve points 3-sigma above the median value divided by number of lightcurves with valid adjacentburstdip2 values
normnburst3doublectNormalized nburst3: Number of good lightcurve points 3-sigma above the median value divided by number of lightcurves with valid nburst3 values
normnburst4doublectNormalized nburst4: Number of good lightcurve points 3-sigma above the median value divided by number of lightcurves with valid nburst4 values
notescharLogbook transcription comment
nplotintctNumber of default points plotted in a lightcurve.
npointsintctTotal number of points, good and bad, in a lightcurve.
npoints_localintct(NPOUT in contour_plot_clip_smooth_correct2.f) number of stars used for the median magnitude correction
npoints_local_1intct(NPOUT in contour_plot_clip_smooth_correct2.f) number of stars used for the median magnitude correction
npoints_local_2intct(NPOUT in contour_plot_clip_smooth_correct2.f) number of stars used for the median magnitude correction
npoutintctnumber of stars used for the median magnitude correction
Npts_exintctNumber of points outside the selected points of a transient candidate lightcurve peak. Synonym for peakExtra.
Npts_TCintctNumber of images in a transient candidate lightcurve peak. Synonym for peakCount.
nslope_60intctNumber points in a lightcurve used to calculate slope_60.
nslope_allintctNumber of points used to calculate slope_all.
nstar0doublectstars in magnitude bin for magnitude-dependent calibration
nstar_magdepintctnumber of bin stars used for the magnitude-dependent correction
NUMBERintSextractor object number in an image. See sextractor manual.
numfakeintctNumber of images not matching GSC2.3.2 objects during defect filtering
numrealintctNumber of images matching GSC2.3.2 objects during defect filtering.
numTilesintctNumber of tiles in the scan pattern
nxintNumber of horizontal bins in a local calibration table
nyintNumber of verticalbins in a local calibration table
objectsCutoffintctIf fewer sextractor objects than this amount, consider the bin empty
oldNumbercharOriginal plate number for renamed plates
orientationenumSeries plate orientation North Forward or Left, Mirrored (deprecated)
outlierCountintctNumber of outlier images on this plate
outlierRatiodoubleFraction of images on this plate which are outliers
pageintLogbook page number synonym for logPage
passBitsintPass identifier. Unused, only bit 1 GSC2.3.2 pass1 is recognized
pathCountintctNumber of SExtractor images in the longest path of the candidate scratch chain
patrolGroupintctPatrol filing group (1-4)
patrolPlateintctPatrol plate flag 0 = wide field telescope (fittedPlateScale less than 350 arcsec/mm), 1 = patrol telescope (fittedPlateScale greater than 350 arcsec/mm)
patternIDintScan pattern
peakCountintctNumber of images in a transient candidate lightcurve peak. Synonym for Npts_TC
peakCountNFintctNumber of good lightcurve points inside the selected transient window from narrow field telescopes
peakCountWFintctNumber of good lightcurve points inside the selected transient window from wide field telescopes
peakDaysdoubledDuration of a transient candidate lightcurve peak
peakDecdoubledegWeighted Declination in degrees of the lightcurve points in the selected transient window. Synonym for Dec_TC
peakDefectCountintctThe number of lightcurve defects in the selected transient window
peakDradRMSdoublearcsecRMS positional error of selected points of a transient candidate lightcurve peak
peakDradRMS2doublearcsecdradRMS2 pointed added in quadrature for selected points of a transient candidate lightcurve peak
peakDradRMS3doublearcsecRMS positional error referred to peakRA and peakDec of selected points of a transient candidate lightcurve peak
peakEventCountintctThe number of peaks in the lightcurve that meet the event criteria
peakEventCount2intctThe number of peaks in the lightcurve eliminating multiple peaks for each transient
peakEventCount3intctThe total number of peaks in the lightcurve, valid or now
peakExtraintctNumber of points outside the selected points of a transient candidate lightcurve peak. Synonym for Npts_ex.
peakMagdoublemagBrightness of the transient candidate lightcurve peak
peakMaxMagdoublemagBrightest magnitude of the transient
peakMinMagdoublemagDimmest magnitude of the transient
peakMultipleCountintctThe number of lightcurve points in the selected transient window from multiple exposure plates
peakNearbyDistancedoublearcsecdistance to nearby stars that are within 2 magnitudes of the brightest or average magnitude of the transient candidate
peakNumberintctOrder of brightness of the selected peak. The brightest peak is 1, the 10th brightest peak is 10
peakOutsideintctNumber of good lightcurve points outside the selected transient window (ngood - peakCount)
peakOutsideNFintctNumber of good lightcurve points outside the selected transient window from narrow field telescopes
peakOutsideWFintctNumber of good lightcurve points outside the selected transient window from wide field telescopes
peakRAdoubledegWeighted Right Ascension in degrees of the lightcurve points in the selected transient window. Synonym for RA_TC
peakRMSdoublemagResidual error after linear lightcurve fitting
peakSlopedoublemag/dSlope of the transient candidate lightcurve after peak
peakSlopeRMSdoublemag/dSlope uncertainty of the transient candidate lightcurve after peak
peakUpperCountintctThe number of points brighter than (peakMaxMag+peakMinMag)/2
peakYeardoubleyrYear of the transient candidate lightcurve peak
PendingFlagintctstack processing pending flag yes: plate has not been found; no, plate has been processed.
PlatecharHCO plate designation (series and number within series)
plateClasscharPlate class
plateCommentcharSpecial scanning status of the plate
plateCountintctNumber of square plates
plateJPEGenumbitIf plate JPEG exists, 'yes'; otherwise 'no'
plateNumberintThe sequential number assigned to a plate in a given plate series from a single telescope or lens
plateReleaseFieldintctPlate Center Release field (DR1-DR12)
plateVersionIdintVersion Id from the photplates table
plate_ddecdoubledegdeclination distance in degrees from the plate center
plate_distdoubledegdistance in degrees from the plate center
plate_dist_1doubledegdistance in degrees from the plate center
plate_dist_2doubledegdistance in degrees from the plate center
plate_dradoubledegright ascension distance in degrees from the plate center
PolyDecRMSdoublepixRMS declination error in pixel from SCAMP polynomial fitting
PolyRARMSdoublepixRMS Right Ascension error in pixels from SCAMP polynomial fitting
PolyRefStarsintctNumber of reference stars used for SCAMP polynomial fitting
portcharDisk drive raid array port
precessionCorrectedenumbitIf 'yes', precession error has been corrected, otherwise 'no'. Deprecated
prevboundenumbitPrevious bound ('b') or unbound ('u') volume in logbook linked list
prevpageintPrevious page in the logbook linked list
prevseriescharPrevious series in the logbook linked list
prevvolumeintPrevious volume in the logbook linked list
Q0intctADU level in quadrant 0 (upper left)
Q1intctADU level in quadrant 1 (upper right)
Q2intctADU level in quadrant 2 (lower left)
Q3intctADU level in quadrant 3 (lower right)
qualifiercharSource of the plate class information
qualityintPlate quality flags
qualitybitscharListing of bits set in plate quality flags
radoubledegRight Ascension in degrees
radiusdoublearcsecRadius of a catlog galaxy in arcsec
raidArrayintRaid array number of which the disk is part of
raidDiskcharLocation in the disk raid array (one-based)
range_isodoublemagThe magnitude range of the lowess magnitude in a lightcurve
range_localdoublemagThe magnitude range of the locally corrected magnitude in a lightcurve
range_local2doublemagThe magnitude range from the second brightest to the second dimmest magnitude in a lightcurve
raPixelsdoublepixOffset in Right Ascension pixels from the previous exposure
RaPMdoublemas/yrRight Ascension proper motion in mas/yr
RaPMSigmadoublemas/yrRight Ascension proper motion error in mas/yr
rarmsdoubledegStandard deviation of lightcurve ra
RaSigmaPMdoublemas/yrRight Ascension proper motion error in mas/yr
ratio1doubleIn defect filtering, the number of images flagged as real divided by the number of images matching the GSC2.3.2 catalog
ratio2doubleIn defect filtering, the number of images flagged as not real divided by the number of images not matching the GSC2.3.2 catalog
ratio3doubleIn defect filtering, the ratio of images matching the GSC2.3.2 catalog and the images not matching the GSC2.3.2 catalog.
ra_1doubledegImage Right Ascension from sextractor
ra_1_1doubledegImage Right Ascension from sextractor
ra_1_2doubledegImage Right Ascension from sextractor
ra_2doubledegCatalog star Right Ascension, precessed to plate epoch
ra_2_1doubledegCatalog star Right Ascension, precessed to plate epoch
ra_2_2doubledegCatalog star Right Ascension, precessed to plate epoch
RA_TCdoubledegWeighted Right Ascension in degrees of the lightcurve points in the selected transient window. Synonym for peakRA.
recordIdintUnique MySQL table index
REFcharThe GSC2.3.2 ID.
referenceintPage reference in History of the Plate Series by Martha Hazen
refmagdoublemagSynonym for the Stdmag, the GSC2.3.2 magnitude.
REFNumberlongStar reference designation expressed as an integer
refstarsintctNumber of reference stars to use for WCS fitting. WCStools 'imwcs' input parameter.
REF_1charThe GSC2.3.2 ID.
REF_2charThe GSC2.3.2 ID.
rejectFlagintLocal calibration bin rejection reason.
reject_countintctNumber of images rejected because of high drad in a spatial bin.
reject_reasonintLightcurve rejection reason.
reject_reason1intUnmasked reject_reason for a lightcurve image
reject_reason2intMasked reject_reason for a lightcurve image
releaseFieldintctDASCH release field (1-12)
rightAscensioncharHH:MM:SSJ2000 Right Ascension
rightMarginintpixRight margin in pixels
rmagdoublemagGSC2.3.2 sdss r magnitude
rmsdoublemagThe average locally corrected magnitude rms error for an entire spatial bin.
rmsdradrms2doubledegStandard deviation of lightcurve dradRMS2
rms_factordoublemagRMS of the lightcurve divided by the median error; valid variables have a larger rms_factor
rms_localdoublemagIn annular9.m, the RMS of the locally corrected good magnitudes in a lightcurve.
rootFlagintIf nonzero, the observation is selected as the root observation of a Transient Candidate
rotationintdegAngle in degrees between original mosaic and mosaic with North up.
rowdoubleKepler satellite CCD row
rowCutoffintctIf greater than equal to this number of empty bins, consider the row empty
scaledoublearcsec/pixPlate scale in arcsec per pixel
scale1doublearcsec/pixFitted scale in arcsec per pixel, first coordinate. WCStools 'imwcs' result.
scale2doublearcsec/pixFitted scale in arcsec per pixel, second coordinate WCStools 'imwcs' result.
scaleDriftdoubleScale drift during WCS fitting. (1- ratio of scales).
scalexdoublearcsec/pixx-axis arcseconds per pixel
scaleydoublearcsec/pixy-axis arcseconds per pixel
scanCommentcharScan comment
scanDatecharY-M-D,h:m:sDate scanned
scanExposuredoubles-3Scanner exposure time in milliseconds
scanJDdoubleJDJulian Date of the plate scan
scanLinearityJDdoubleJDJulian Date of the last linearity test prior to the scan
scanNumberintScan number for this plate
scratchFlagintbitSExtractor image is a plate scratch
sdsscolordoublemagSDSS g - r color
selectedintbitEntry has been selected.
sensorIndexintctMagnetic sensor on the plate washer
separationdoublepixFitting separation in pixels (obsolete use in arcsec in fithistory). WCStools 'imwcs' result.
sequenceintMeasurement position within a lightcurve graph
serialcharDisk serial number
seriescharPlate series indicating the telescope or lens used to photograph the plate
seriesIdintIndex into the plate series table
Sextractor_BlenddoublectNumber of good points with the sextractor blend or neighbors bits set
SEXTRNUMBERintSynonym for NUMBER to avoid MySQL keyword
SFLAGSintFLAGS bits from sextractor
Sig_TCdoublearcsecMaximum value of peakDradRMS2 and peakDradRMS3
slope_60doublemag-3/yrlightcurve slope for points before 1960
slope_60_errdoublemag-3/yrlightcurve slope standard deviation for points before 1960
slope_alldoublemag-3/yrlightcurve slope
slope_all_errdoublemag-3/yrlightcurve slope standard deviation
SMOOTH_BACKGROUNDdoublectSmoothed background at centroid position (deprecated)
solutionHeaderenumbitIf 'no', the exposureNumber column is really the solutionNumber; otherwise 'yes'
solutionNumberintThe zero-based exposure number in the order found by astrometry.wcs in a multiple exposure image
sourceenumSource of plates table entry 'Catalog','Logbook', or 'JPEG' expanded with 'logindex','estimate', or 'noknownlog' in logindexnew
spatial_binshortbyteannular ring on the plate where the star appears (1 = centermost, 9 = outermost)
spatial_bin_1shortbyteannular ring on the plate where the star appears (1 = centermost, 9 = outermost)
spatial_bin_2shortbyteannular ring on the plate where the star appears (1 = centermost, 9 = outermost)
speeddoublectUnrelated to astronomy
squareBorderenumbitIf 'yes' solution used a square region; otherwise 'no'. WCStools 'imwcs' input parameter.
squareCountintctNumber of square emulsion plates
squareCutoffintctValue of maxIy-minIy. If less than equal the plate is square
src_namecharSearch query source name
stackFilingBinintctPlate Stack Filing Location (1-226)
stackLocationcharLocation in the plate stacks
starCountintctNumber of images in for the gsc bin in a photometry database file
startcharHH:MM:SSLogbook time of exposure start
startupJDdoubleJDJulian Date of the scanner software startup
stationIndexintctUnrelated to astronomy
statusenumbitWCS fit result 'succeeded' or 'failed'
std2doublectRatio of bin 9 clipped and 3 sigma clipped ADU to the median ADU
StdmagdoublemagGSC2.3.2 magj magnitude
Stdmag_1doublemagGSC2.3.2 magj magnitude
Stdmag_2doublemagGSC2.3.2 magj magnitude
stopcharHH:MM:SSLogbook time of exposure end
suffixcharSuffix for duplicate plate numbers
suffixBaseintSuffix base for duplicate plate numbers. Original plateNumber is (plateNumber - suffixBase)
THETA_IMAGEdoubledegPosition angle (CCW/x) determined by sextractor
THETA_J2000doubledegImage angle in degrees East of North. See sextractor manual.
THETA_J2000_1doubledegImage angle in degrees East of North. See sextractor manual.
THETA_J2000_2doubledegImage angle in degrees East of North. See sextractor manual.
THRESHOLDdoublectDetection threshold above background. See sextractor manual.
THRESHOLD_1doublectDetection threshold above background. See sextractor manual.
THRESHOLD_2doublectDetection threshold above background. See sextractor manual.
tileintTile position number in the scan pattern. Actual tiles have name Exposure_'tile'.fit
tileJDdoubleJDJulian Date of a flatfield tile
timeAccuracydoubledAccuracy of logbook time in days
timeSourceenumbitExposure time source, either 'Catalog' or 'Logbook'
timeSpentintsSeconds used for WCS fitting
timeStampcharY-M-D,h:m:sTime of last write to the database
timeTypecharKnown date type ('EST', 'LST', 'UT', 'SASE' ...)
toleranceintpixWCS fitting tolerance in pixels. WCStools 'imwcs' input parameter.
topMarginintpixTop plate margin in pixels
transformsetTransform between scan and mosaic 'Flip' and/or 'Mirror'. Used with 'rotation' to match raw tiles with positions in the final mosaic.
turnOffForwardintctMagnetic turn off position in the forward direction on the plate washer
turnOffReverseintctMagnetic turn off position in the reverse direction on the plate washer
turnOnForwardintctMagnetic turn on position in the forward direction on the plate washer
turnOnReverseintctMagnetic turn on position in the reverse direction on the plate washer
typecharThe GSC2.3.2 ID.
ucdcharUnified Content Descriptor
unboundenumbitLogbook volume is bound if 'b' otherwise 'u'
uncertainenumbitIf 'yes', there is uncertainty in the location
unitcharVariable physical unit
unmatchedintctNumber of good (AFLAGS == 0) images unmatched to the catalog for a plate
updateflagenumbitIf 'yes' then the star summary data needs to be updated; otherwise 'no'
upper_limitdoublemagupper limit: limiting_mag - 2*error, where the error is the overall RMS in the annular9.m photom fitting
variableDescriptioncharDescription of variable
variableFlagintctIf 1, object is in the AAVSO VSX database
variableNamecharVariable name in this table
verifiedenumbitObservatory location is approximate if 'no'; otherwise 'yes';
versioncharY-M-D,h:m:sDate logbook transcription was last edited
versionDatecharY-M-D,h:m:sPhotometry data version date
versionIdintIndex into the photometry version table for GSC2.3.2 stars
versionId1intIndex into the photometry version table for Kepler Input Catalog stars
versionId2intIndex into the photometry version table for APASS catalog stars
versionNamecharPhotometry data version name
VFlagintbitIf nonzero, the catalog star has an uncertain magnitude.
VFlag_1intbitIf nonzero, the catalog star has an uncertain magnitude.
VFlag_2intbitIf nonzero, the catalog star has an uncertain magnitude.
volumeintLogbook volume numbers
VTmagdoublemagGSC2.3.2 Tycho2 visual magnitude
wcsnrefintctNumber of stars used for WCS matching
WCSSourceenumbitSource of the WCS fit, either 'Logbook' or 'imWCS'
widthintpixMosaic width
widthJPEGintpixLength of the x axis of the CameraPC image
wLongitudedoubledegWest Longitude of the observatory in degrees
xAutoExposeTabledoublem-3Aerotech X-axis Auto-expose position
xbinsintNumber of horizontal smoothing bins (normally 50)
xcoorddoublepixMosaix x-axis of the bin center for magnitude-dependent calibration
xcoord_magdepdoublepixx-axis center of the magnitude-dependent correction bin
xPixJPEGintpixX-axis brightest selected spot on the CameraPC image
xPosdoublem-3Aerotech X position for the tile
xvaldoublepixx-axis position in pixels for calculation of dxmedian and dymedian.
X_IMAGEdoublepixMosaic x-axis pixel position of the image. See sextractor manual.
X_IMAGE_1doublepixMosaic x-axis pixel position of the image. See sextractor manual.
X_IMAGE_2doublepixMosaic x-axis pixel position of the image. See sextractor manual.
X_WORLDdoubledegBarycenter position along world x axis. See sextractor manual.
yAutoExposeTabledoublem-3Aerotech Y-axis Auto-expose position
ybinsintNumber of vertical smoothing bins (normally 50)
ycoorddoublepixMosaic y-axis of the bin center for magnitude-dependent calibration
ycoord_magdepdoublepixy-axis center of the magntiude-dependent correction bin
yeardoubleyrCalendar year of an image
yPixJPEGintpixY-axis brightest selected spot on the CameraPC image
yPosdoublem-3Aerotech Y position for the tile
yrbegindoubleyrBeginning calendar year of a lightcurve
yrenddoubleyrEnding calendar year of a lightcurve
yvaldoublepixy-axis position in pixels for calculation of dxmedian and dymedian
Y_IMAGEdoublepixMosaix y-axis pixel position of the image. See sextractor manual.
Y_IMAGE_1doublepixMosaix y-axis pixel position of the image. See sextractor manual.
Y_IMAGE_2doublepixMosaix y-axis pixel position of the image. See sextractor manual.
Y_WORLDdoubledegbarycenter position along world y axis. See sextractor manual.
Zfinaldoublemagdmag correction for magnitude-dependent calibration
zoutdoublemagmedian magnitude correction needed in a given plate ragion
Zrms1doublemaginitial rms before correction for magnitude-dependent calibration
Zrms2doublemagfinal rms after correction for magnitude-dependent calibration

Number of database variables: 791

Notes on Database Variables

Plate Selection

Plates are referenced by a plate series which usually identifies individual telescopes; and a plate number, which usually increases monotonically for every plate exposed at the telescope. Any disk files related to a plate have the extended designation:
{series}{plateNumber}_{mosaicNumber}_{binning}{rotationString}ww{solutionString}{qualifierString}{fileSuffix}
where
rotationString is null for zero degrees and r{rotation} for other angles
solutionString is null for the first solution and _s{solutionNumber} for successive solutions of a multiple-exposure plate
qualifierString is null for the primary GSC2.3.2-calibrated database stream, _{qualifier} for alternate streams such as 'kepler' for photometry data calibrated with the Kepler Input Catalog and 'apass' for data calibrated with the APASS catalog)
fileSuffix defines the type of file.

Observatory Location

Telescopes did not necessary remain at one location but were moved between observatories worldwide

Plate Class

The plate class serves to identify the kind of exposure that was taken and is useful in filtering out plates that may require special techniques for analysis or for selecting plates taken with particular filters or gratings.

Plate Jacket Photographs

Prior to scanning, a photograph was taken of every plate jacket to capture standard plate information and additional notations that may have been made by observers or researchers

Plate Annotation Photographs

Many researchers made ink annotations on the rear of plates to identify objects. If such annotations were found prior to scanning, they were photographed and then the annotations were cleaned from the plate. The emulsion side of the plates was never cleaned.

Fitted Plate Scale

Average plate scale from available WCS fits in arc seconds per mm. This column can not be comprehensive because of the following anomalies: These anomalies are currently hard-coded in the database access software.

Exposure Information

Many of the plates have multiple exposures to increase the dynamic range of the emulsion, include calibration fields, or look for short-period brightness changes. For each exposure, the Right Ascension and Declination are calculated for the center of the plate.

Geocentric and Heliocentric Dates

The time of the exposure is expressed as a geocentric date. The corresponding heliocentric date is calculated with reference to the right ascension and declination of the center of the plate. Since some plate series contain plates which cover wide areas of the sky, the heliocentric date may vary significantly from the value at the center of the plate. If the user specifies a specific location or object in the search page, then the Julian Date result will show the heliocentric date for that object in the search page results table.

Plate Center Source and Date Source

The initial digitization effort involved typing in the card catalog for the stacks. Approximately 129,000 catalog entries were digitized prior to the availability of initial results from the plate scanner. At this point, the scanner results showed that the Julian Date information available in the card catalog was not of sufficient accuracy for the discovery of objects such as eclipsing binaries. The decision was then made to photograph and digitize the logbooks which were the source of the card catalog data. Information from the card catalog is still designated as Catalog and this information will be eventually replaced by information from the logbooks which are designated by Logbook. Because the logbook plate centers have a median error of about 0.5 degrees, these logbook plate centers will eventually be replaced with the results of wcs fitting to star catalogs which are designated by imWCS or WCS. For the source of the exposure time, only Catalog and Logbook apply.

Exposure Notes

The digitized card catalog information contains a remarks field which is preserved in the database.

Nearby Objects

This list consists of a series of nearby objects followed by their distance in arcseconds. The list is valid only to within 0.5 degrees of a given search center. The list consists of one of each of the following three object types:

Time Accuracy

There are a number of automated checks possible on the digitized logbook data. The results of these checks is a time accuracy estimate to give researchers an indication of the reliability of the quoted time. Time accuracy is not available for catalog entries. A default value of -1 is used for an unknown time accuracy.

Logbook Information

The database contains images of 663 bound logbook volumes and approximately 500 loose leaf logbooks. Some of the data has been digitized at Harvard and in India, but currently the data is being digitized by volunteers at the American Museum of Natural History in New York City. We appreciate the assistance of Dr Michael Shara, Curator, Dept. of Astrophysics, Holly Klug, Supervisor of Explainer Programs, Dept. of Volunteer Services and their team of volunteers. All of these photographs are available for browsing.

Exposure Start and Stop Times

Exposure start and stop times were generally recorded in Local Sidereal Time, but in some cases Eastern Standard Time or Universal Time was used. The time type in use can usually be determined from the plate center right ascension and the hour angle. The final reported exposure time in the plate exposure information table is the average of the start and stop times. These times are given to a varying number of significant digits and are used to initialze the time accuracy entry.

Hour Angle

The hour angle was reported not only in the standard sense of increasing time West of the meridian, but sometimes the opposite. Occasionally errors in the sign of the angle can be detected from the context of the rest of the observation.

Logbook Remark

Because comments entered into the logbooks have no defined formats, the typists were instructed to enter either Y or N. Some transcriptions, however, do have transcriptions of the original logbook remark. If this field is blank, the logbook remark was not transcribed or may appear in the notes column.

Logbook Notes

Entries are usually entered at Harvard for certain targets of opportunity. These notes contain the reason for transcription.

Errors Detected by Automated Checks

A number of automatic checks of the logbook data is possible. If one of these checks fail, then the reported time accuracy is reduced accordingly or simply set to 1 day if the actual error magnitude is not obvious. The following definition list shows the error check flags that appear in the database should one of these tests fail. The versions referred to below are used to differentiate new logbook data being entered into the database from previously existing logbook data.

Error CodeDescription
Discrepancy Discrepancy between India and Cambridge transcriptions. (Deprecated because of exposure number uncertainty for multiple exposures)
E vs W Fixed E Hour angle mistaken for W or vice-versa. Automatically corrected
Bad Date Fixed Bad date fixed from nearby data (Not yet implemented)
Bad Date Bad date which has not been corrected
12H Fixed 12 Hour LST error Fixed
Exposure Times Disagree Exposure Times Disagree
Non-Numeric Exposure Non-numeric exposure time
Daylight Exposure Exposure while sun is up
Bad Volume Number Volume numbers disagree
HA not LST minus RA Error in Hour Angle
Field Length Exceeded Field Length Exceeded
Bad Remark Remark field not "Y" or "N", corrected to "N"
Bad Multiple (OLD) Multiple exposures on different pages - compared with old version
Bad Multiple (NEW) Multiple exposures on different pages - compared with current version
Decreasing plateNumber Plate number not monotonically increasing
Unknown Time Type Unable to determine if time is LST, UT, or EST because longitide is missing
Below Horizon The telescope is apparently pointing below the horizon
Bad Page Error decoding the logbook volume and page
Bad Time Type Best type type is not the expected time type
Unrecognized Time Type Can not decode the time type in the transcription
Unexpected Time Type Transcription time type disagrees with the ranges table
Bad RA Right Ascension less than 0 hours or greater than 24 hours. NOTE: In some cases, the Right Ascension was deliberately written greater than 24 hours. For these cases, 24 hours should be subtracted from the Right Ascension.
Bad Declination Declination less than -90 degrees or greater than +90 degrees. Note: In some cases, the Declination was deliberately written greater than 90 degrees or less than 90 degrees. For these cases, subtract positive declinations from 180 and negative declinations from -180 and add 12H to the hour angle.
Incomplete Julian Day Julian Day fractional part is missing
Julian Day Mismatch Transcribed Julian Day does not match calculated Julian Day
Time Decreasing Exposure time not monotonically increasing

Scan and Mosaic Information

Scan Number If a plate is scanned multiple times, the scan number keeps track of individual scans.

Mosaic Number

If a second mosaic must be created from a single scan using a new mosaic algorithm, the mosaic number identifies the algorithm. If available, a new mosaic number is assigned with the corresponding scan number. If not available, new mosaic numbers are assigned from unused scan and mosaic numbers. Afterwards, a new scan number will not be assigned an existing scan or mosaic number.

Scan Date

The scan date is important for identifying early scans which are likely to be of lower quality while the scanner was being tested. Because of the mutually exclusive means of assigning scan and mosaic numbers, the scan date is a better way to determine the order of scanning.

Average Tile ADU

Tiles are individual exposures of the scanner camera which are later combined into a mosaic. Since the scanner camera has a 12 bit CCD readout, the average tile ADU will range from the bias level of 50 ADU to the maximum level of 4095 ADU.

Average and Maximum Tile Saturation

In order to improve the dynamic range for dark plates, the scanner exposure time is automatically adjusted. However, pixels imaging film defects and other areas of missing emulsion will saturate. The saturation count is the number of pixels at 4095 ADU on a per tile basis. Since there are 16M pixels per exposure, this is the upper limit of saturation.

Scan Comment

If the average and maximum tile saturation levels reach preset amounts, the scanner software will automatically enter Saturation Error in this field. The scanner operator is free to add any additional comments describing the state of the plate or the reason for the scan.

Mosaic Comment

If a special issue arises with the creation of the mosaic, a comment will be entered here. Currently, the only comment for some mosaics is Linearity Bug which means that the mosaic should be rejected because of a bug in the early version of the mosaic algorithm.

Mosaic Binning

Normally, the mosaic algorithm generates two mosaics simultaneously. These are the full size mosaics with 1 in this field and a 16 x 16 binned mosaic with 16 in this field. Some other binning factors for early mosaics are also present, but the binning factor must be a power of two.

WCS Fit Solution

This entry indicates whether the stars on a mosaic have been fitted to a standard catalog so that an accurate plate center is known.

Mosaic Rotation

If a WCS fit solution is available, this entry indicates how much the original mosaic must be rotated in a clockwise direction so that North is up.

Photometry Pipeline Information

Plotting Symbols

The following plotting symbols are used. These symbols are defined for the WIP Plotting Software Package. The plotting codes appear in the flags database column listed above.

SymbolPlotting CodeDescription
Solid circle17for a good point
Small solid circle17.5for a good point at the edge of the plate
Open circle22for a large error point
Small open circle22.5for a large error point at the edge of the plate
Arrow pointing down31for not found at the indicated limiting magnitude
Small arrow pointing down31.5for not found at the edge of the plate
Asterisk 3 for a suspected plate defect
Triangle 7 for a high astrometric error object
Open square 6 for a Pickering Wedge object
Solid square 16 for an object with high or unknown extinction
Arrow pointing up 30 for an object too bright for the photometric algorithm
Diamond 11.5 for a blended object
Cusped square 10.5 for a high local correction object
Letter b 98.5 for an object considered blended by sextractor, but not by the pipeline because of the low threshold we used in running sextractor
Letter c 99.5 for a good object without color correction
Letter q 13.5 for a good object in a plate with: multiple exposures, gratings, red or yellow filters, Pickering Wedge, spectra, fails colorterm metropolis algorithm, or fails colorterm limits.

AFLAGS

This field is a bitmap of photometry pipeline warnings which exclude a magnitude measurement from being included in the summary statistics for a star. Bits 16-18 come from the GSC2.3.2 class field, but only the code for a non-star is currently defined. Bits 20-23 are cases of blended stars. A case B blend is a single image that covers multiple GSC2.3.2 stars. A case C blend is a single GSC2.3.2 star that can be matched to multiple images. A case D blend is multiple GSC2.3.2 stars matching multiple images. Processing of this blend involves subdividing it into smaller groups of matches with the above blend designations: i.e. DA, DB, and DC. The showflags utility can decode the AFLAGS field into its constituent bits. Bits marked with an asterisk below are not used to filter measurements when computing overall lightcurve RMS values on the website home page.

Bit PositionDecimal ValueHexadecimal ValueDescription
6 64 40 *Object has a high background level
7 128 80 *Plate fails quality criterion
8 256 100 Unmatched object on a multiple-exposure plate
9 512 200 *Object has more than 1.1 hour time uncertainty preventing an accuracte extinction calculation
10 1024 400 *Object is a multiple exposure blend
11 2048 800 Maximum isophotonic rms exceeded
12 4096 1000 Maximum locally smoothed rms exceeded
13 8192 2000 Star too close to the limiting magnitude
14 16384 4000 Star is in bin 9
15 32768 8000 Object rejected because bin has unknown drad.
16-18 65536 10000 Galaxy (not in GSC 2.3.2)
16-18 131072 20000 Blend (not in GSC 2.3.2)
16-18 196608 30000 Object is Non-star
16-18 262144 40000 Unclassified (not in GSC 2.3.2)
16-18 327680 50000 *Defect (not in GSC 2.3.2)
16-18 458752 70000 Duplicate Star (Added for DASCH project)
19 524288 80000 *Uncertain catalog magnitude (In the APASS catalog all Tycho2 and GSC2.3.2 objects are marked variable to remove them from the magnitude calculation algorithms.)
20 1048576 100000 *Case B - blended
21 2097152 200000 Case C - overlapping Sextractor hits for one GSC star
22 4194304 400000 Case D - mixture of cases B and C
23 8388608 800000 Object has a drad three times the bin drad or is in a bad spatial bin or local bin
24 16777216 1000000 *Object is a Pickering Wedge object
25 33554432 2000000 Object fails the defect filter
26 67108864 4000000 *Copy of the Sextractor blended flag
27 134217728 8000000 Rejected blended object - avoid plotting a limiting magnitude.
28 268435456 10000000 Rejected because of high smoothing correction
29 536870912 20000000 Object is too bright for accurate magnitudes
30 1073741824 40000000 *Object is within 23.5 degrees of horizon

BFLAGS

This field is a bitmap of photometry pipeline conditions which provide additional information concerning how the image was processed. Bits 12-15 are GSC2.3.2 magnitude substitution flags which depend on the setting of bit 23. The showflags utility can decode the BFLAGS field into its constituent bits. Note that bits 12-15 now contain the definitions defined in MAGFlags below.

Bit PositionDecimal ValueHexadecimal ValueDescription
0 1 1 Object has neighbors
1 2 2 Object was blended with another
2 4 4 At least one pixel is saturated
3 8 8 Object is too close to the image boundary
4 16 10 Object aperture data incomplete or corrupted
5 32 20 Object isophotal data incomplete or corrupted
6 64 40 Memory overflow during deblending
7 128 80 Memory overflow during extraction
8 256 100 Magnitude adjusted for a blended star (currently unused)
9 512 200 Object has low drad but it is in a high drad bin (currently unused)
10 1024 400 Object PSF considered saturated (ISO5/ISO4 > 0.7) and ((BACKGROUND+FLUX_MAX) > 7500)
11 2048 800 Magnitude-dependent calibration has been applied.
12 4096 1000 JMag substituted for JpgMag (deprecated)
13 8192 2000 BMag substituted for JpgMag (deprecated)
14 16384 4000 RMag substituted for FpgMag (deprecated)
15 32768 8000 VMag substituted for FpgMag (deprecated)
16 65536 10000 Good star processed by the pipeline
17 131072 20000 Star has been calibrated with the lowess fit
18 262144 40000 Star has been locally calibrated
19 524288 80000 Magnitude has been corrected for extinction
20 1048576 100000 Magnitude calibration not possible because the star is too bright
21 2097152 200000 Bin has a valid color correction
22 4194304 400000 Color correction used the metropolis algorighm
23 8388608 800000 Interpret bits 12-15 as Kepler Input Catalog Source bits;
24 16777216 1000000 Match at end of pipeline.
25 33554432 2000000 High proper motion uncertainty
27 134217728 8000000 Spatial bin fails QUALITY_COLORTERM
28 268435456 10000000 Ra and dec have been adjusted by the bin medians
29 536870912 20000000 This plate has an uncertain Julian Date
30 1073741824 40000000 Catalog position corrected for proper motion

FitWCS

This field is a bitmap of status flags which summarize the state of pipeline processing for the mosaic.

NameDecimal ValueDescription
Selected 1 Selected for fitting
MikeShawFit 2 Previously fitted by Mike Shaw (deprecated)
Completed 4 Fitting process successful
Copied 8 Fit results copied to head cluster (deprecated)
MultFailedAstrometry 16 Fit results failed AstrometryWCS for next exposure
MultFailedSeparation 32 Fit results failed the separation criteria for the next exposure
MultSucceeded 64 Fit results succeeded for the next exposure
StaleSolution 128 Better astrometry invalidates this solution
StaleExposureNumber 256 The exposure number of this solution has been changed
Wedge 512 This is a Pickering Wedge plate
FilterBlendedTimeout 1024 The filterblended routine timed out
NoAllObjects 2048 The allobjects file for this solution is missing
DuplicateREFCount 4096 This solution shares the same stars with a previous solution
ColortermCrash 8192 The colorterm.m script has crashed and needs to be rerun
InaccuratePV 16384 The SCAMP polynomial fit has significant inaccuracy
NoneFile 32768 The {}_none.db file produced by filter_multiple is present. NOTE: this entry is an internal software flag that does not appear in database files.

MAGFlag

This variable contains flags used in the processing of the GSC2.3.2 catalog. These flags are necessary because the GSC2.3.2 catalog contains magnitudes from multiple source catalogs which used different color filters. Furthermore, there are bugs in the GSC2.3.2 catalog which generate multiple entries for certain bright sources. The goal to put all of the GSC2.3.2 objects on a single color system became possible with the availability of the Kepler Input Catalog. Initially, bits 1-4 were used to identify simple substitutions of JMag or BMag for an unavailable JpgMAG; and RMag or VMag for an unavailable FpgMAG. These definitions are now deprecated. Bits 5-6 are used to eliminate duplicate references to a star and then cleared once this goal has been accomplished. When the Kepler Input Catalog became available, color transformations are now used to put all of the six different populations in the GSC2.3.2 catalog into the reference system of the Kepler Input Catalog and then into the JpgMAG/FpgMAG reference system of the majority of GSC2.3.2 stars. The labels beginning with COLOR identify these six populations. These labels were chosen so as not to create a conflict with the older definitions during pipeline processing. For the Kepler Input Catalog, definitions preceded by KEPLER_CQ designate the source of the Kepler catalog object. This variable is currently unused for the APASS catalog.

LabelBitDecimal ValueHexadecimal ValueDescription
COLOR_JPGMAG_FPGMAG x 0 0 No substitutions
COLOR_BMAG_FOR_JPGMAG x 3 3 BMag substituted for JpgMag
COLOR_VMAG_FOR_FPGMAG x 4 4 VMag substituted for FpgMag
COLOR_VMAG_BMAG_FOR_JPGMAG_FPGMAG x 5 5 BMag substituted for JpgMag and VMag substituted for FpgMag
COLOR_TYCHO x 6 6 This is a Tycho Source
COLOR_SKYMAP x 7 7 This is a Skymap Source
JMAG_FOR_JPGMAG 1 1 1 JMag substituted for JpgMag (deprecated)
BMAG_FOR_JPGMAG 2 2 2 BMag substituted for JpgMag (deprecated)
RMAG_FOR_FPGMAG 3 4 4 RMag substituted for FpgMag (deprecated)
VMAG_FOR_FPGMAG 4 8 8 VMag substituted for FpgMag (deprecated)
SAME_LOCATION 5 16 10 Rejected because location (RA and DEC) is identical (INTERNAL)
SAME_ENTRY 6 32 20 Rejected because all fields are identical. (INTERNAL)
DUPLICATE_PAIR 7 64 40 Part of a pair of location identical objects. Reject only objects with bit 6 set (INTERNAL)
TYCHO_SOURCE 8 128 80 This is a Tycho source (INTERNAL)
SKYMAP_SOURCE 9 256 100 This is a Skymap source (INTERNAL)
KEPLER_CQ_SCP 0 Kepler Catalog Source, valid when BFLAGS bit 23 is set
KEPLER_CQ_2MASS 1 Kepler Catalog Source, valid when BFLAGS bit 23 is set
KEPLER_CQ_PHOTO 2 Kepler Catalog Source, valid when BFLAGS bit 23 is set
KEPLER_CQ_TYBV 3 Kepler Catalog Source, valid when BFLAGS bit 23 is set
KEPLER_CQ_UNCAL 4 Kepler Catalog Source, valid when BFLAGS bit 23 is set
KEPLER_CQ_NOCAL 5 Kepler Catalog Source, valid when BFLAGS bit 23 is set

quality

On December 11, 2009, Sumin Tang made the following request to eliminate common causes of outliers in her search for interesting variables: Only use the very good points AND(not blends, not defects, not high drad, not within 23.5 degrees of horizon, not in bin 9, not within 0.5 mag of the limiting magnitude, not high iso rms, not high local smoothing rms, not Pickering wedge object) in good blue plates AND(colorterm between -0.5 and 0.25 in the bin, colorflag==2, not dny plates, not dnr plates, not multiple exposures, not Pickering wedge plates) for the calculation of min_local, max_local, range_local, min_local2, max_local2, range_local2, median_local, rms_local, ngood, clip_median_local, clip_rms_local, clip_ngood, median_iso, range_iso in the ID table. For individual images, most of these conditions are handled by selecting only magntiudes with AFLAGS equal to zero. The remaining conditions are handled by this plate quality flag which marks plates that are second quality. Note that the colorterm flag does not appear in the database because this condition is dependent on the annular_bin that the image appears in. The colorterm limits were shifted to -0.067 to 0.283 when the recalibrated GSC2.3.2 catalog was introduced in January, 2010. These new colorterm limits represent the 5% and 95% tails of the new colorterm distribution for blue plates in the M44 region. Colorterm limits were revised again in November, 2012 after over 30,000 plates were scanned and additional calibration catalogs came into use. For the GSC2.3.2 catalog, the colorterm bit is set when the colorterm is outside the -0.097 to 0.410 range; for the Kepler Input Catalog, the range is -0.102 to 0.409; and the APASS calibration, the range is -0.146 to 0.195.

NOTE: in the following table, bits 10 and 11 are not in all data tables provided by the website. These bits appear only in some of the tables provided by the website lightcurve plotter and may appear only if specifically requested by the user.

NameBit PositionDecimal ValueDescription
multiple 0 1 Multiple exposure plate
grating 1 2 Grating plate
color 2 4 Color filter used for plate
colorterm 3 8 Image fails colorterm limits
wedge 4 16 Pickering Wedge plate
spectra 5 32 Spectra plate
saturated 6 64 Saturated Images (ISO5/ISO4 > 0.7) and ((BACKGROUND+FLUX_MAX) > 7500)
nomagdep 7 128 Image not Magnitude-dependent Corrected
patrol 8 256 Wide-Field Patrol Telescopes
nonpatrol 9 512 Narrow Field Telescopes
limiting 10 1024 Show Limiting Magnitudes
undetected11 2048 Plot plates where the object was not detected
trailed 12 4096 Image trailed (ELLIPTICITY exceeds 0.6)

REFNumber

In order to reduce disk space, GSC2.3.2, Kepler, APASS, and DASCH designations were replaced with a sixty-four bit integer. To convert from the catalog reference (REF) to the integer (REFNumber), the following rules apply:

CatalogConversion
Unmatched objects Replace NONEwith 0
GSC2.3.2 Replace N with 11 and S with 12. Be sure to retain any leading zeroes in the numeric part of the GSC2.3.2 identification.
Kepler Input Catalog Replace K with 2
DASCH DASCH and APASS designations are similar to SDSS designations which are based on Right Ascension and declination. DASCH Jhhmmss.sSddmmss becomes 3hhmmsssSddmmss where S is 1 for positive declination and 2 for negative declination. For example, DASCH J083039.3+140709 becomes 308303931140709. The only difference with APASS designations is that a 4 prefix replaces the 3 prefix.

rejectFlag

These flags are set whenever the collection of images in the local bin do not meet overall quality requirements for the local bin. Such flagged images are not used in statistical analyses.

NameDecimal ValueDescription
DMAG_REJECT_HIZOUT 1 local correction bin rejected because the local correction is out of range
DMAG_REJECT_MEDIAN 2 local correction bin rejected because median brightness dimmer than the limiting magnitude
DMAG_REJECT_DRAD 4 local correction bin rejected because majority of stars have high drad

reject_reason

The lightcurve plotter compiles summaries of the reasons why individual magntiude measurements should be rejected from consideration. These flags are compiled mostly from AFLAGS with some additional error conditions.

Bit Name Bit PositionDecimal ValueHexadecimal ValueDescription
ERROR 0 1 1 Error processing this Plate
OFFPLATE 1 2 2 Object not on plate
BINFAILURE 2 4 4 No data for this spatial bin
UNDETECTED 3 8 8 Object undetected on this plate
WEDGE 4 16 10 Object is a Pickering wedge
DRAD 5 32 20 Object has high DRAD
DEFECT 6 64 40 Object failed the defect filter
HIZOUT 7 128 80 Object in bad spatial bin
BLEND_NOMATCH 8 256 100 Object in glare of brighter object
BLEND 9 512 200 Object is blended
BIN9 10 1024 400 Object is in bin 9
LOCAL_RMS 11 2048 800 Object has high locally calibrated RMS
LIMITING_MAG 12 4096 1000 Object within 0.75 mag of the limiting magnitude
TOO_BRIGHT 13 8192 2000 Object is too bright
LOW_ALTITUDE 14 16384 4000 Object is too close to the horizon
ISO_RMS 15 32768 8000 Object has high lowess RMS
DRADBIN 16 131072 20000 Object is in a bin with too high RMS drad
COMPLEX_BLEND 17 262144 40000 Object has a case c or d blend
MULTIPLE_BLEND 18 524288 80000 Object is a multiple blend
UNCERTAIN_DATE 19 1048576 100000 Object has an uncertain date for extinction calculation
MULTIPLE_NONE 20 2097152 200000 Unmatched object on a multiple exposure plate
QUALITY 21 4194304 400000 Plate fails quality criterion - see quality
SATURATED 22 8388608 800000 Object is saturated
NOMAGDEP 23 167772161000000 Object has no magnituded-dependent correction.
BACKGROUND 24 335544322000000 Object has a high background level.

fatalError

These error codes are generated by the CheckProgress routine which is used to ensure completeness when the pipeline is rerun for all plates because of major revisions. Codes less than 100 indicate completed execution. Codes between 99 and 1000 indicate incomplete execution. Codes greater than or equal to 999 are software consistency checks.

NameDecimal ValueDescription
FATAL_NO_MATCHFILE 1 No match file found
FATAL_NO_ALLOBJECTS 2 recover_points failed
FATAL_ASTROMETRY 3 find_astrometry2 failed
FATAL_ASTROMETRY2 4 find_astrometry2 failed. None file does not exist
FATAL_MAX_SOLUTION 5 Too many solutions
FATAL_ASTROMETRYWCS_FAIL 6 AstrometryWCS failed
FATAL_MULT_FAILED_SEPARATION 7 Second solution is too close to the first
FATAL_MISSING_ALLOBJECTS 8 Allobjects missing for higher order solution
FATAL_NO_FILTER_MULTIPLE 100 filter_multiple did not run
FATAL_NO_ASTROMETRY 200 find_astrometry2 did not run
FATAL_STALE_FILTER_MULTIPLE 300 Latest summary allobjects file not later than individual solution allobject file
FATAL_NO_SUMMARY_ALLOBJECTS 400 Summary allobjects file does not exist
FATAL_NO_WCSHISTORY 500 No AstrometryWCS history available
FATAL_STALE_ALLOBJECTS 600 Allobjects stale for higher order solution - run filter_multiple
FATAL_STALE_ALLOBJECTS2 700 Allobjects stale for higher order solution - run rest of pipeline
FATAL_MISSING_MATCHFILE 800 matchfile missing for higher order solution
FATAL_STALE_MATCHFILE 900 stale matchfile for higher order solution
FATAL_NO_NEXT_MOSAIC 10000 MULTSUCCEEDED without a mosaic
FATAL_UNKNOWN_MOSAIC_STATE 20000 Unknown mosaic state
FATAL_NO_LAST_MOSAIC 30000 Could not get the last mosaic
FATAL_ORPHAN_NEXT_MOSAIC 40000 Have next mosaic but no astromfithistory
FATAL_ORPHAN_NEXT_MOSAIC2 50000 Have next mosaic but no find_astrometry
FATAL_ORPHAN_NEXT_MOSAIC3 60000 Have next mosaic but no none file
FATAL_ORPHAN_LAST_SUCCESS 70000 Have successful next mosaic but no astromfithistory
FATAL_ORPHAN_LAST_SUCCESS2 80000 Have successful next mosaic but no find_astrometry
FATAL_ORPHAN_LAST_SUCCESS3 90000 Have successful next mosaic but no none file
FATAL_ORPHAN_GOOD_ASTROMFITHISTORY 100000 Have good astromfithistory but no find_astrometry
FATAL_ORPHAN_GOOD_ASTROMFITHISTORY2 110000 Have good astromfithistory but no none file
FATAL_ORPHAN_SUCCESS_FILE 120000 Have an astrometry success file, but no none file

magcal_local_rms

This is the estimated error of the locally corrected magnitude measurement. Since adding the spatial bin rms and local correction bin rms in quadrature produces errors which are higher than the rms of the final lightcurve for constant stars, the following procedure recalculates the error based on stars of similar magnitude in the spatial bin.

  1. For each spatial bin, take all of the images which have successfully completed local calibration and sort them by magcal_magdep, the locally corrected and magnitude-dependent corrected magnitude.
  2. After sorting, divide the images into magnitude bins with 20 stars per bin. Within each bin find the 3-sigma clipped rms of (magcal_magdep - Stdmag) where Stdmag is the catalog magnitude adjusted by extinction. Since the mean and median values of this rms are expected to be zero, the rms calculation is zero-based rather than based on the mean.
  3. For every image within the spatial bin and magnitude bin, use the rms calculated in step 2. Images dimmer the limiting magnitude will have the rms set to 99.0 and images brighter than the brightest magnitude will use the rms of the brightest magnitude bin.