Parameters

Select which parameters you want to examine:

Object parameters (e.g. - 'P001', 'P002', etc. tables)
POSS I Field parameters ('plates' table)
Astrometric Fit Parameters ('astrom' table)
Photometric Fit Parameters ('photom' table)
Photometric Standards ('standards' table)
POSS I scanned data removed from MAPS Catalog ('cuts' table)
All the parameters in the MAPS Catalog database (list all of the above)

'object' Table Parameters:

Object data is broken up into 632 database tables, each with the name of the POSS I field the objects are on (e.g. 'P001', 'P002', etc). The following parameters are stored for each of the over 89 million objects in the MAPS Catalog:

Field Name	Definition
plateid	MAPS POSS I Field Number
starnumO, starnumE	Image raster number for the O and E plates respectively. The plateid combined with starnumO uniquely identifies an object in the MAPS Catalog and thus the official IAU designation for objects in the MAPS Catalog is "MAPS Pplateid-starnumO" (e.g. - The object with starnumO '34256' and plateid '1' would have the IAU designation 'MAPS P001-0034256'). NON-UNIQUENESS WARNING: First of all, because of the nature of the POSS I survey, a single object in the sky can appear on multiple POSS I plates if they overlap in their sky coverage. So a single object in the sky can have mutliple MAPS Catalog records. Furthermore, the E raster number may not be unique for a given POSS I field. Object matching was done from O to E, so sometimes a single E plate object was the closest counterpart to two O plate images. Such (rare) cases are flagged in the dupl parameter (see below).
ra	Right Ascension (equatorial B1950.0 coordinates on the FK4 system). Stored internally as a 1000*seconds integer.
decl	Declination (equatorial B1950.0 coordinates on the FK4 system). Stored internally as a 1000*arcseconds integer.
raJ	Right Ascension (ecliptic J2000.0 coordinates on the FK5 system). Stored internally as a 1000*seconds integer.
declJ	Declination (ecliptic J2000.0 coordinates on the FK5 system). Stored internally as a 1000*arcseconds integer.
l	Galactic Longitude (l^II system). Stored internally as a 1000*arcseconds integer.
b	Galactic Latitude (l^II system). Stored internally as a 1000*arcseconds integer.
Ebv_S	E(B-V) for this position based on the bilinear interpolation of the dust maps from Schlegel, Finkbeiner, & Davis (1998). If we combine the UV - NIR extinction law from Cardelli, Clayton and Mathis 1989, ApJ, 345, 245 with conversion of E(B-V) to A_V by assuming A_V = 3E(B-V), then the extinction corrections in the POSS I bandpasses becomes: A_O = 1.4646 A_V = 1.4646 * 3E(B-V) A_E = 0.8120 A_V = 0.8120 * 3*E(B-V)
magiO, magiE	Integrated magnitude for this object on the O and E plates respectively. This magnitude is appropriate for extended objects.
magdO, magdE	"stellar" magnitude (determined from the diameter-magnitude relation) for this object on the O and E plates respectively. This magnitude is appropriate for point sources.
colori	O-E color for this object (computed using integrated magnitudes)
colord	O-E color (computed using "stellar" magnitudes)
mean_sbO, mean_sbE	Mean Surface Brightness (in magnitudes/arcsec^2) for this object on the O and E plates respectively.
diaO, diaE	Major-axis diameter for this object on the O and E plates respectively (in arcseconds). NOTE: Diameters of 0.00 may be stored for some objects where the ellipticity was listed as 1.00 or -0.001. All these objects have flagO or flagE denoting the reason for disregarding the validity of the data.
ellO, ellE	The ellipticity (based on a moments analysis of the entire image) for this object on the O and E plates respectively. NOTE: Cases where the ellipticity could not be determined are listed as having ellipticity -0.001. And ellipticity of greater than 0.95 likely means the object is a scratch or crossed a striped boundary in the MAPS scans. The flagO and flagE fields note stripe crossing objects, but not scratches.
thetaO, thetaE	The position angle (based on a moments analysis of the entire image) for this object on the O and E plates respectively. This is measured in degrees East of North in B1950.0 coordinates. NOTE: A position angle of 0.00 may be stored for some objects where the ellipticity was listed as 1.00 or -0.001. This value is invalid in these cases. To eliminate all non-real 0.00 position angles from your sample, check that flagO and/or flagE also equal 0.
thetaJO, thetaJE	Same as thetaO or thetaE except this is measured in J2000.0 coordinates and computed based on thetaO or thetaE. NOTE: If the position angle in B1950.0 (thetaO or thetaE) equals 0.00, be sure to check that the corresponding flagO and/or flagE also equal 0 to be sure thetaJO and/or thetaJE is valid.
thetaGO, thetaGE	Same as thetaO or thetaE except this is measured in Galactic coordinates and computed based on thetaO or thetaE. NOTE: If the position angle in B1950.0 (thetaO or thetaE) equals 0.00, be sure to check that the corresponding flagO and/or flagE also equal 0 to be sure thetaGO and/or thetaGE is valid.
galnodO, galnodE	An estimate of the probability that object is a galaxy based on the O and E plate images respectively. For determining if a object is a galaxy, the O plate galnod value is the more appropriate value as the images were generally better on the O plates.
reffO, reffE	The half-light radius for this object on the O and E plates respectively (in arcseconds)
mir1O, mir2O, mir1E, mir2E	The first and second moments of the flux in this object's image on the O and E plates respectively. This is measured in degrees East of North.
psatO, psatE	The percentage saturation of this image on the O and E plates respectively. One of the major problems with photographic plates is that when all the silver halides in the emulsion have reacted with incoming light, additional light can no longer be detected. That is, the image has saturated. The more saturated an image is, the more difficult it can be to extract accurate photometric parameters for the object.
c32O, c42O, c32E, c42E	The C(r₇₅/r₅₀) [c₃₂] and C(r₁₀₀/r₅₀) [c₄₂] concentration indices for this object on the O and E plates respectively. The concentration index is a measure of how centrally concentrated the light in a object is.
tavgO, tskyO, tavgE, tskyE	The average transmittance and sky transmittance for this object on the O and E plates respectively.
XsctO, YsctO, XsctE, YsctE	The X and Y position for the centroid of this object (and the region around it) on the O and E plates respectively. Measured in units of EREs (1 ERE = 0.366μ, 0".0245).
flagO, flagE	This is a flag for bad image data for this object on the O and E plates respectively. The flags have the following meanings: 0 - OK (no problems noted) 1 - Moments analysis error 2 - Image classifier error 3 - Preprocessing ell suggests this is a scratch 4 - Clipped image on scanning stripe boundary 5 - There is no background scan coverage of image 6 - Negative sky intensity estimate This is the same value as recorded in the 'photom' table for this field and emulsion.
dupl	The number of times this starnumE was matched to a starnumO. In most cases this should be "1" (a unique cross-identification).