II/306 The SDSS Photometric Catalog, Release 8 (Adelman-McCarthy+, 2011)
The SDSS Photometric Catalog, Release 8
Adelman-McCarthy J.K. et al.
<To be published>
=2011yCat.2306....0A 2011yCat.2306....0A
ADC_Keywords: Surveys; Photometry, SDSS ; Redshifts
Keywords: atlases - catalogs - surveys
Abstract:
Description:
Official SDSS-III Acknowledgement
We request that the following be added to the acknowledgement section
of any paper using data from the SDSS-III.
Funding for SDSS-III has been provided by the Alfred P. Sloan
Foundation, the Participating Institutions, the National Science
Foundation, and the U.S. Department of Energy Office of Science. The
SDSS-III web site is http://www.sdss3.org/.
SDSS-III is managed by the Astrophysical Research Consortium for the
Participating Institutions of the SDSS-III Collaboration including the
University of Arizona, the Brazilian Participation Group, Brookhaven
National Laboratory, University of Cambridge, University of Florida,
the French Participation Group, the German Participation Group, the
Instituto de Astrofisica de Canarias, the Michigan State/Notre
Dame/JINA Participation Group, Johns Hopkins University, Lawrence
Berkeley National Laboratory, Max Planck Institute for Astrophysics,
New Mexico State University, New York University, Ohio State
University, Pennsylvania State University, University of Portsmouth,
Princeton University, the Spanish Participation Group, University of
Tokyo, University of Utah, Vanderbilt University, University of
Virginia, University of Washington, and Yale University.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sdss8.sam 977 125 *Sample output of the SDSS photometric catalog
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Note on sdss8.sam: a sample close to the point (0,0) is given in "sdss8.sam".
The catalog described here is a subset of the full SDSS catalog
available from http://www.sdss3.org/dr8/ restricted to primary and
secondary photo objects, and with a selection of the columns of the
full catalog. Column names (labels) frequently differ from their
original names, in which case the original name is added to the
description of the original column.
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
http://www.sdss.org/ : The SDSS Home Page
http://www.sdss3.org/dr8/ : The Eighth SDSS Data Release Home Page (2011)
Byte-by-byte Description of file: sdss8.sam
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Bytes Format Units Label Explanations
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1- 19 I19 --- objID SDSS unique object identifier (2)
21- 30 F10.6 deg RAdeg Right Ascension of the object (ICRS) (ra)
32- 41 F10.6 deg DEdeg Declination of the object (ICRS) (dec)
43- 43 I1 --- mode [1,2] 1: primary (469,053,874 sources),
2: secondary (324,960,076 sources).
45- 45 A1 --- q_mode [+] '+' indicates clean photometry
(105,969,748 sources with mode 1+)
47- 47 I1 --- cl Type (class) of object (3=galaxy, 6=star) (1)
49- 67 A19 --- SDSS8 SDSS-DR8 name, based on J2000 position
69- 69 A1 --- m_SDSS8 [*] The asterisk indicates that 2 different SDSS
objects share the same SDSS8 name
71- 71 I1 --- R [8] Release inclusion (all observations were
reprocessed, value is always 8)
73- 92 A20 --- SDSS-ID [0-9 -] SDSS object identifier (2)
94-112 I19 --- SpObjID Pointer to the spectrum of object, or 0 (7)
114-132 I19 --- parentID Pointer to parent (if object deblended)
134-153 I20 --- flags Photo Object Attribute flags (3)
155-157 I3 --- Status Hexadecimal status (4)
159-166 F8.3 arcsec e_RAdeg Mean error on RAdeg (raErr)
168-175 F8.3 arcsec e_DEdeg Mean error on DEdeg (decErr)
177-185 F9.4 yr ObsDate Mean Observation date
187-187 I1 --- Q Quality of the observation (0=unknown):
1=bad 2=acceptable 3=good 4=missing 5=hole (6)
189-196 F8.5 --- zsp ? Spectroscopic redshift (when SpObjID>0) (7)
198-204 F7.5 --- e_zsp ? Mean error on zsp (7)
206-211 F6.3 mag umag ? Model magnitude in u filter, AB scale (u) (5)
213-217 F5.3 mag e_umag ? Mean error on umag (err_u)
219-224 F6.3 mag gmag ? Model magnitude in g filter, AB scale (g) (5)
226-230 F5.3 mag e_gmag ? Mean error on gmag (err_g)
232-237 F6.3 mag rmag ? Model magnitude in r filter, AB scale (r) (5)
239-243 F5.3 mag e_rmag ? Mean error on rmag (err_r)
245-250 F6.3 mag imag ? Model magnitude in i filter, AB scale (i) (5)
252-256 F5.3 mag e_imag ? Mean error on imag (err_i)
258-263 F6.3 mag zmag ? Model magnitude in z filter, AB scale (z) (5)
265-269 F5.3 mag e_zmag ? Mean error on zmag (err_z)
271-290 I20 --- uFlags Detection flags, u band (flags_u)(3)
292-292 I1 --- us [0,1] 0=notStar, 1=Star in u band (probPSF_u)
294-294 I1 --- uc [0,9] Phototype in u band, 6=Star (type_u) (1)
296-304 F9.4 yr uDate Date of observation in u band (6)
306-311 F6.3 mag u'mag ? Model magnitude in u filter (= umag) (5)
313-318 F6.3 mag e_u'mag ? Mean error on u'mag (= e_umag)
320-325 F6.3 mag upmag ? PSF magnitude in u band (psfMag_u)
327-332 F6.3 mag e_upmag ? Mean error on upmag (psfMagErr_u)
334-339 F6.3 mag uPmag ? Petrosian magnitude in u band (petroMag_u)
341-346 F6.3 mag e_uPmag ? Mean error on uPmag (petroMagErr_u)
348-354 F7.3 arcsec uPrad ? Petrosian radius in u band (petroRad_u)
356-362 F7.3 arcsec e_uPrad ? Mean error in uPrad (petroRadErr_u)
364-372 F9.2 arcsec uoRA ? Offset of u position along RA (offsetRa_u)
374-380 F7.2 arcsec uoDE ? Offset of u position along Dec (offsetDec_u)
382-388 F7.3 arcsec udVrad ? de Vaucouleurs fit radius, u band (deVRad_u)
390-394 F5.3 arcsec udVell ? de Vaucouleurs fit ellipt, u band (1-deVAB_u)
396-400 F5.1 deg uPA ? Position angle of dVrad in u band (deVPhi_u)
402-421 I20 --- gFlags Detection flags, g band (flags_g)(3)
423-423 I1 --- gs [0,1] 0=notStar, 1=Star in g band (probPSF_g)
425-425 I1 --- gc [0,9] Phototype in g band, 6=Star (type_g) (1)
427-435 F9.4 yr gDate Date of observation in g band (6)
437-442 F6.3 mag g'mag ? Model magnitude in g filter (= gmag) (5)
444-449 F6.3 mag e_g'mag ? Mean error on g'mag (= e_gmag)
451-456 F6.3 mag gpmag ? PSF magnitude in g band (psfMag_g)
458-463 F6.3 mag e_gpmag ? Mean error on gpmag (psfMagErr_g)
465-470 F6.3 mag gPmag ? Petrosian magnitude in g band (petroMag_g)
472-477 F6.3 mag e_gPmag ? Mean error on gPmag (petroMagErr_g)
479-485 F7.3 arcsec gPrad ? Petrosian radius in g band (petroMagErr_g)
487-493 F7.3 arcsec e_gPrad ? Mean error in gPrad (petroMagErr_g)
495-501 F7.2 arcsec goRA ? Offset of g position along RA (offsetRa_g)
503-509 F7.2 arcsec goDE ? Offset of g position along Dec (offsetDec_g)
511-517 F7.3 arcsec gdVrad ? de Vaucouleurs fit radius, g band (deVRad_g)
519-523 F5.3 arcsec gdVell ? de Vaucouleurs fit ellipt, g band (1-deVAB_g)
525-529 F5.1 deg gPA ? Position angle of dVrad in g band (deVPhi_g)
531-550 I20 --- rFlags Detection flags, r band (flags_r)(3)
552-552 I1 --- rs [0,1] 0=notStar, 1=Star in r band (probPSF_r)
554-554 I1 --- rc [0,9] Phototype in r band, 6=Star (type_r) (1)
556-564 F9.4 yr rDate Date of observation in r band (6)
566-571 F6.3 mag r'mag ? Model magnitude in r filter (= rmag) (5)
573-578 F6.3 mag e_r'mag ? Mean error on r'mag (= e_rmag)
580-585 F6.3 mag rpmag ? PSF magnitude in r band (psfMag_r)
587-592 F6.3 mag e_rpmag ? Mean error on rpmag (psfMagErr_r)
594-599 F6.3 mag rPmag ? Petrosian magnitude in r band (petroMag_r)
601-606 F6.3 mag e_rPmag ? Mean error on rPmag (petroMagErr_r)
608-614 F7.3 arcsec rPrad ? Petrosian radius in r band (petroMagErr_r)
616-622 F7.3 arcsec e_rPrad ? Mean error in rPrad (petroMagErr_r)
624-627 F4.2 arcsec roRA ? Offset of r position along RA (offsetRa_r)
629-632 F4.2 arcsec roDE ? Offset of r position along Dec (offsetDec_r)
634-640 F7.3 arcsec rdVrad ? de Vaucouleurs fit radius, r band (deVRad_r)
642-646 F5.3 arcsec rdVell ? de Vaucouleurs fit ellipt, r band (1-deVAB_r)
648-652 F5.1 deg rPA ? Position angle of dVrad in r band (deVPhi_r)
654-673 I20 --- iFlags Detection flags, i band (flags_i)(3)
675-675 I1 --- is [0,1] 0=notStar, 1=Star in i band (probPSF_i)
677-677 I1 --- ic [0,9] Phototype in i band, 6=Star (type_i) (1)
679-687 F9.4 yr iDate Date of observation in i band (6)
689-694 F6.3 mag i'mag ? Model magnitude in i filter (= imag) (5)
696-701 F6.3 mag e_i'mag ? Mean error on i'mag (= e_imag)
703-708 F6.3 mag ipmag ? PSF magnitude in i band (psfMag_i)
710-715 F6.3 mag e_ipmag ? Mean error on ipmag (psfMagErr_i)
717-722 F6.3 mag iPmag ? Petrosian magnitude in i band (petroMag_i)
724-729 F6.3 mag e_iPmag ? Mean error on iPmag (petroMagErr_i)
731-737 F7.3 arcsec iPrad ? Petrosian radius in i band (petroMagErr_i)
739-745 F7.3 arcsec e_iPrad ? Mean error in iPrad (petroMagErr_i)
747-753 F7.2 arcsec ioRA ? Offset of i position along RA (offsetRa_i)
755-761 F7.2 arcsec ioDE ? Offset of i position along Dec (offsetDec_i)
763-769 F7.3 arcsec idVrad ? de Vaucouleurs fit radius, i band (deVRad_i)
771-775 F5.3 arcsec idVell ? de Vaucouleurs fit ellipt, i band (1-deVAB_i)
777-781 F5.1 deg iPA ? Position angle of dVrad in i band (deVPhi_i)
783-802 I20 --- zFlags Detection flags, z band (flags_z)(3)
804-804 I1 --- zs [0,1] 0=notStar, 1=Star in z band (probPSF_z)
806-806 I1 --- zc [0,9] Phototype in z band, 6=Star (type_z) (1)
808-816 F9.4 yr zDate Date of observation in z band (6)
818-823 F6.3 mag z'mag ? Model magnitude in z filter (= zmag) (5)
825-830 F6.3 mag e_z'mag ? Mean error on z'mag (= e_zmag)
832-837 F6.3 mag zpmag ? PSF magnitude in z band (psfMag_z)
839-844 F6.3 mag e_zpmag ? Mean error on zpmag (psfMagErr_z)
846-851 F6.3 mag zPmag ? Petrosian magnitude in z band (petroMag_z)
853-858 F6.3 mag e_zPmag ? Mean error on zPmag (petroMagErr_z)
860-866 F7.3 arcsec zPrad ? Petrosian radius in z band (petroMagErr_z)
868-874 F7.3 arcsec e_zPrad ? Mean error in zPrad (petroMagErr_z)
876-882 F7.2 arcsec zoRA ? Offset of z position along RA (offsetRa_z)
884-890 F7.2 arcsec zoDE ? Offset of z position along Dec (offsetDec_z)
892-898 F7.3 arcsec zdVrad ? de Vaucouleurs fit radius, z band (deVRad_z)
900-904 F5.3 arcsec zdVell ? de Vaucouleurs fit ellipt, z band (1-deVAB_z)
906-910 F5.1 deg zPA ? Position angle of dVrad in z band (deVPhi_z)
912-916 I5 mas/yr pmRA ? Proper motion along RightAscension (pmRa) (8)
918-920 I3 mas/yr e_pmRA ? Mean error on pmRA (pmRaErr) (8)
922-926 I5 mas/yr pmDE ? Proper motion along Declination (pmDec) (8)
928-930 I3 mas/yr e_pmDE ? Mean error on pmDE (pmDecErr) (8)
932-936 F5.3 arcsec sigRA ? RMS residual of proper motion fit in RA (8)
938-943 F6.3 arcsec sigDE ? RMS residual of proper motion fit in Dec (8)
945-945 I1 --- M Number of USNO-B objects matched within 1arcsec (match) (8)
947-947 I1 --- N Number of detections used in the pm fit, including SDSS (nFit) (8)
949-952 F4.1 mag g(O) ? Magnitude from O plate recalibrated to g (8)
954-957 F4.1 mag r(E) ? Magnitude from E plate recalibrated to r (8)
959-962 F4.1 mag g(J) ? Magnitude from J plate recalibrated to g (8)
964-967 F4.1 mag r(F) ? Magnitude from F plate recalibrated to r (8)
969-972 F4.1 mag i(N) ? Magnitude from N plate recalibrated to i (8)
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Note (1): the type (class) is numbered as follows:
0 = Unknown: Object type is not known.
25 = Cosmic-ray track (not used).
26 = Defect (not used)
27 = Galaxy: An extended object composed of many stars and other matter.
28 = Ghost: Object created by reflected or refracted light. (not used)
29 = KnownObject: Object came from some other catalog (not yet used)
30 = Star: A a self-luminous gaseous celestial body.
31 = Trail: A satellite or asteroid or meteor trail. (not yet used)
32 = Sky: Blank sky spectrogram (no objects in this arcsecond area).
33 = NotAType
Note (2): the SDSS identifier is composed of the 5 numbers run, rerun
(301), camcol (1-6), field (11-1001) and object (1-4000). The SDSS-ID
is written run-rerun-cam-field-obj (5 numbers and 4 dashes). The objID
is also combined from these numbers (the ≪n operator represents the
left shift of n bits, i.e. a multiplication by 2n):
objID = skyVersion≪59 + rerun≪48 + run≪32 + camcol≪29
+ field≪16 + obj
(in the case of DR8, skyVersion=2 and rerun=301, i.e. objID is in the
range 1237645472596754432-1237926947573465087
(hexa 112d000000000000-112dffffffffffff).
Note (3): flags written in hexadecimal, full description available at
http://skyserver.sdss3.org/dr8/en/help/browser/enum.asp?n=PhotoFlags
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0000000000000001 = CANONICAL_CENTER Measurements used the center in r*
0000000000000002 = BRIGHT Object detected in bright object-finding
0000000000000004 = EDGE Object is too close to edge of frame
0000000000000008 = BLENDED Multiple peaks detected
0000000000000010 = CHILD Product of deblending a BLENDED object.
0000000000000020 = PEAKCENTER Position of peak pixel rather than ML
0000000000000040 = NODEBLEND No deblending attempted on BLENDED object
0000000000000080 = NOPROFILE Radial profile could not be estimated
0000000000000100 = NOPETRO No valid Petrosian radius found
0000000000000200 = MANYPETRO More than one Petrosian radius found.
0000000000000400 = NOPETRO_BIG Petrosian radius beyond radial profile.
0000000000000800 = DEBLENDTOOMANY_PEAKS More than 25 peaks in this object
0000000000001000 = COSMIC_RAY Contains a pixel part of a cosmic ray.
0000000000002000 = MANYR50 More than one 50% light radius.
0000000000004000 = MANYR90 More than one 90% light radius.
0000000000008000 = BAD_RADIAL Some points in radial profile S/N<0
0000000000010000 = INCOMPLETE_PROFILE Petrosian radius intersects frame edge
0000000000020000 = INTERP Pixel(s) determined by interpolation.
0000000000040000 = SATURATED Saturated pixel(s)
0000000000080000 = NOTCHECKED Not checked for local peaks
0000000000100000 = SUBTRACTED BRIGHT object, wings subtracted
0000000000200000 = NOSTOKES No measured Stokes params
0000000000400000 = BADSKY Sky level so bad that highest pixel <0.
0000000000800000 = PETROFAINT Petrosian radius(es) rejected for low SB
0000000001000000 = TOO_LARGE Object too large to measure its profile
0000000002000000 = DEBLENDEDASPSF Deblender treated obj as PSF
0000000004000000 = DEBLEND_PRUNED At least one child was removed
0000000008000000 = ELLIPFAINT Object center fainter than the isophote
0000000010000000 = BINNED1 Object detected in 1x1 binned image
0000000020000000 = BINNED2 Object detected in 2x2 binned image
0000000040000000 = BINNED4 Object detected in 4x4 binned image
0000000080000000 = MOVED Possibly moving object
0000000100000000 = DEBLENDEDASMOVING A MOVED object treated as moving.
0000000200000000 = NODEBLEND_MOVING A MOVED object not treated as moving.
0000000400000000 = TOOFEWDETECTIONS Too few detections to deblend as moving.
0000000800000000 = BADMOVINGFIT Moving fit too poor to be believable.
0000001000000000 = STATIONARY Object consistent with being stationary.
0000002000000000 = PEAKSTOOCLOSE Some peaks merged into a single peak.
0000004000000000 = MEDIAN_CENTER Center given is of median-smoothed image.
0000008000000000 = LOCAL_EDGE Center too close to an edge.
0000010000000000 = BADCOUNTSERROR Too few good pixels, error underestimated
0000020000000000 = BADMOVINGFIT_CHILD Moving child's velocity fit too poor
0000040000000000 = DEBLENDUNASSIGNEDFLUX After deblending flux not assigned
0000080000000000 = SATUR_CENTER Center is close to saturated pixel(s)
0000100000000000 = INTERP_CENTER Center is close to interpolated pixel(s)
0000200000000000 = DEBLENDEDATEDGE Object close to edge was deblended
0000400000000000 = DEBLEND_NOPEAK No detected peak within this child
0000800000000000 = PSFFLUXINTERP PSF flux from interpolated pixels > 20%
0001000000000000 = TOOFEWGOOD_DETECTIONS Too few good detections
0002000000000000 = CENTEROFFAIMAGE At least one peak's center lay off image
0004000000000000 = DEBLEND_DEGENERATE Identical candidate children, 1 retained
0008000000000000 = BRIGHTESTGALAXYCHILD Brightest member classified as galaxy
0010000000000000 = CANONICAL_BAND Band chosen as 'Canonical', generally r
0020000000000000 = AMOMENT_FAINT Object too faint to measure moments
0040000000000000 = AMOMENT_SHIFT Centroid shift too large
0080000000000000 = AMOMENT_MAXITER Maximum number of iterations exceeded
0100000000000000 = MAYBE_CR Object could actually be a cosmic ray
0200000000000000 = MAYBE_EGHOST Object could actually be a ghost
0400000000000000 = NOTCHECKED_CENTER Object center in a region not searched
0800000000000000 = OBJECT2HASSATUR_DN Trails included in estimated flux.
1000000000000044 = OBJECT2DEBLENDPEEPHOLE Deblend modified by peephole
2000000000000044 = GROWN_MERGED Growing led to a merger
4000000000000044 = HAS_CENTER Object has a canonical center
8000000000000044 = RESERVED Not used
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Note (4): status flags written in hexadecimal, full description available at
http://skyserver.sdss3.org/dr8/en/help/browser/enum.asp?n=ResolveStatus
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00000001 = RUN_PRIMARY Object status set in reference to its own run
00000002 = RUN_RAMP Object in what would be the overlap area of a field
00000004 = RUN_OVERLAPONLY Object only appears in the overlap between 2 fields
00000008 = RUN_IGNORE Bright or parent object that should be ignored
00000010 = RUN_EDGE Object near lowest or highest column
00000020 = RUN_DUPLICATE Duplicate measurements of same pixels in 2 fields
00000100 = SURVEY_PRIMARY Primary observation within survey (mode=1)
00000200 = SURVEY_BEST Best observation in full survey, but not primary.
00000400 = SURVEY_SECONDARY Repeat (independent) observation (mode=2)
00000800 = SURVEY_BADFIELD In field with score=0
00001000 = SURVEY_EDGE Not kept as secondary
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Note (5):
The response curves of the SDSS filters (u g r i z) can be found on
the SDSS pages: http://www.sdss.org/dr5/instruments/imager/index.html
The central wavelength and FWHM are:
-----------------------------------------------
(nm) u' g' r' i' z'
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lambda 354.3 477.0 623.1 762.5 913.4
FWHM 56.7 138.7 137.3 152.6 95.0
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Note that the ugriz magnitudes are not exactly on the AB scale
for the u-band (uAB=umag-0.04) and z-band (zAB=zmag+0.02)
(http://www.sdss.org/DR7/algorithms/fluxcal.html)
Note (6): column from the "Fields" table.
Dates of the observations for each colour, and their average.
Note (7): column from the "SpecObjAll" table. The "SpObjID" is composed
of plate + mjd + fiber + run2d with formula (the ≪n operator
represents the left shift of n bits, i.e. a multiplication by 2n):
SpObjID = (plate≪50)+((mjd-50000)≪24)+(fiber≪38)+(run2d≪10)
Note (8): column from the "ProperMotions" table.
Acknowledgements:
It is a pleasure to thank Aniruddha R. Thakar, who prepared the
huge files to build this catalog.
History:
* 26-Nov-2025: format migration (CDS)
(End) Francois Ochsenbein [CDS] 28-Sep-2011