II/267 The SDSS Photometric Catalog, Release 4 (Adelman-McCarthy+, 2006)
The SDSS Photometric Catalog, Release 4
Adelman-McCarthy J.K. et al.
<Astrophys. J. Suppl. Ser., 162, 38 (2006)>
=2006ApJS..162...38A 2006ApJS..162...38A
ADC_Keywords: Surveys; Photometry, SDSS
Keywords: atlases - catalogs - surveys
Description:
The present catalog is a subset of the data release 4 of the Sloan
Digital Sky Survey (SDSS), restricted to primary and secondary photo
objects (i.e. objects from PhotoPrimary of PhotoSecondary tables) and
restricted to the columns described in the "Byte-by-Byte" description
below. The complete SDSS data release 4 catalog is available from
http://www.sdss.org/dr4/
The Sloan Digital Sky Survey (SDSS) will map in detail one-quarter of
the entire sky, determining the positions and absolute brightnesses
of more than 100 million celestial objects. It will also measure the
distances to more than a million galaxies and quasars. Apache Point
Observatory, site of the SDSS telescopes, is operated by the
Astrophysical Research Consortium (ARC).
Funding for the SDSS has been provided by the Alfred P. Sloan
Foundation, the Participating Institutions, the National Aeronautics
and Space Administration, the National Science Foundation, the U.S.
Department of Energy, the Japanese Monbukagakusho, the Max Planck
Society, and the Higher Education Funding Council for England.
The SDSS is a joint project of The University of Chicago, Fermilab,
the Institute for Advanced Study, the Japan Participation Group, The
Johns Hopkins University, the Korean Scientist Group, Los Alamos
National Laboratory, the Max-Planck-Institute for Astronomy (MPIA),
the Max-Planck-Institute for Astrophysics (MPA), New Mexico State
University, University of Pittsburgh, University of Portsmouth,
Princeton University, the United States Naval Observatory, and the
University of Washington.
All details about ADSS at http://www.sdss.org/dr4/
Acknowledging SDSS:
The usage of the SDSS should be acknowledged, see
http://www.sdss.org/collaboration/credits.html
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sdss4.sam 903 1000 *Sample output of the SDSS-DR4 photometric catalog
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Note on sdss4.sam: a sample close to the zero point is given here.
The catalog described here is a subset of the full SDSS-DR4 catalog
available from http://www.sdss.org/dr4/ 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:
http://www.sdss.org/ : The SDSS Home Page
http://www.sdss.org/dr4/ : The SDSS Data Release 4 Home Page
Byte-by-byte Description of file: sdss4.sam
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Bytes Format Units Label Explanations
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1- 18 I18 --- objID [0-9] SDSS unique object identifier (2)
20- 29 F10.6 deg RAdeg Right Ascension of the object (J2000)
31- 40 F10.6 deg DEdeg Declination of the object (J2000)
42- 42 I1 --- mode [1,2] 1: primary, 2: secondary 3: family object (not here)
44- 44 I1 --- cl Type (class) of the object (type) (1)
46- 64 A19 --- SDSS Recommended SDSS name, based on J2000 position
66- 66 A1 --- m_SDSS [*] The asterisk indicates that 2 different SDSS objects share the same SDSS name
68- 68 I1 --- R [3] Release: blank for new, '3' included in DR3
70- 84 A15 --- SDSS-ID [0-9.] SDSS object identifier (2)
86-103 I18 --- SpObjID Pointer to the spectrum of object, or 0
105-122 I18 --- parentID Pointer to parent (if object deblended)
124-125 I2 --- rerun [40,44] Re-run number (2)
127-142 A16 --- flags Photo Object Attribute flags (3)
144-147 I4 --- Status Hexadecimal status (4)
149-156 F8.3 arcsec e_RAdeg Mean error on RAdeg
158-165 F8.3 arcsec e_DEdeg Mean error on DEdeg
167-171 F5.2 --- ccPos Correlation between e_RAdeg and e_DEdeg
173-181 F9.4 yr ObsDate Observation date
183-183 I1 --- Q Quality of the observation: 1=bad 2=acceptable 3=good 4=missing 5=hole
185-190 F6.3 mag umag ?Model magnitude in u filter (5)
192-196 F5.3 mag e_umag ?Mean error on umag
198-203 F6.3 mag gmag ?Model magnitude in g filter (5)
205-209 F5.3 mag e_gmag ?Mean error on gmag
211-216 F6.3 mag rmag ?Model magnitude in r filter (5)
218-222 F5.3 mag e_rmag ?Mean error on rmag
224-229 F6.3 mag imag ?Model magnitude in i filter (5)
231-235 F5.3 mag e_imag ?Mean error on imag
237-242 F6.3 mag zmag ?Model magnitude in z filter (5)
244-248 F5.3 mag e_zmag ?Mean error on zmag
250-265 A16 --- uFlags [0-9A-F] Detection flags, u band (flags_u)(3)
267-267 I1 --- us [0-2] 0=notStar, 1=Star in u band (probPSF_u)
269-269 I1 --- uc [0,9] Phototype in u band, 6=Star (type_u) (1)
271-279 F9.4 yr uDate Date of observation in u band
281-286 F6.3 mag u'mag ? Model magnitude in u filter (= umag) (5)
288-293 F6.3 mag e_u'mag ? Mean error on u'mag (= e_umag)
295-300 F6.3 mag upmag ? PSF magnitude in u band (psfMag_u)
302-307 F6.3 mag e_upmag ? Mean error on upmag (psfMagErr_u)
309-314 F6.3 mag uPmag ? Petrosian magnitude in u band (petroMag_u)
316-321 F6.3 mag e_uPmag ? Mean error on uPmag (petroMagErr_u)
323-329 F7.3 arcsec uPrad ? Petrosian radius in u band (petroRad_u)
331-337 F7.3 arcsec e_uPrad ? Mean error in uPrad (petroRadErr_u)
339-344 F6.2 arcsec uoRA ? Offset of u position along RA (offsetRa_u)
346-352 F7.2 arcsec uoDE ? Offset of u position along Dec (offsetDec_u)
354-362 F9.3 arcsec uisoA ? Isophotal major diameter in u band (isoA_u)
364-372 F9.3 arcsec uisoB ? Isophotal minor diameter in u band (isoB_u)
374-380 F7.1 deg uPA ? Position angle of uisoA in u band (isoPhi_u)
382-397 A16 --- gFlags [0-9A-F] Detection flags, g band (flags_g)(3)
399-399 I1 --- gs [0-2] 0=notStar, 1=Star in g band (probPSF_g)
401-401 I1 --- gc [0,9] Phototype in g band, 6=Star (type_g) (1)
403-411 F9.4 yr gDate Date of observation in g band
413-418 F6.3 mag g'mag ? Model magnitude in g filter (= gmag) (5)
420-425 F6.3 mag e_g'mag ? Mean error on g'mag (= e_gmag)
427-432 F6.3 mag gpmag ? PSF magnitude in g band (psfMag_g)
434-439 F6.3 mag e_gpmag ? Mean error on gpmag (psfMagErr_g)
441-446 F6.3 mag gPmag ? Petrosian magnitude in g band (petroMag_g)
448-453 F6.3 mag e_gPmag ? Mean error on gPmag (petroMagErr_g)
455-461 F7.3 arcsec gPrad ? Petrosian radius in g band (petroMagErr_g)
463-469 F7.3 arcsec e_gPrad ? Mean error in gPrad (petroMagErr_g)
471-476 F6.2 arcsec goRA ? Offset of g position along RA (offsetRa_g)
478-484 F7.2 arcsec goDE ? Offset of g position along Dec (offsetDec_g)
486-494 F9.3 arcsec gisoA ? Isophotal major diameter in g band (isoA_g)
496-504 F9.3 arcsec gisoB ? Isophotal minor diameter in g band (isoB_g)
506-512 F7.1 deg gPA ? Position angle of gisoA in g band (isoPhi_g)
514-529 A16 --- rFlags [0-9A-F] Detection flags, r band (flags_r)(3)
531-531 I1 --- rs [0-2] 0=notStar, 1=Star in r band (probPSF_r)
533-533 I1 --- rc [0,9] Phototype in r band, 6=Star (type_r) (1)
535-543 F9.4 yr rDate Date of observation in r band
545-550 F6.3 mag r'mag ? Model magnitude in r filter (= rmag) (5)
552-557 F6.3 mag e_r'mag ? Mean error on r'mag (= e_rmag)
559-564 F6.3 mag rpmag ? PSF magnitude in r band (psfMag_r)
566-571 F6.3 mag e_rpmag ? Mean error on rpmag (psfMagErr_r)
573-578 F6.3 mag rPmag ? Petrosian magnitude in r band (petroMag_r)
580-585 F6.3 mag e_rPmag ? Mean error on rPmag (petroMagErr_r)
587-593 F7.3 arcsec rPrad ? Petrosian radius in r band (petroMagErr_r)
595-601 F7.3 arcsec e_rPrad ? Mean error in rPrad (petroMagErr_r)
603-606 F4.2 arcsec roRA ? Offset of r position along RA (offsetRa_r)
608-611 F4.2 arcsec roDE ? Offset of r position along Dec (offsetDec_r)
613-621 F9.3 arcsec risoA ? Isophotal major diameter in r band (isoA_r)
623-631 F9.3 arcsec risoB ? Isophotal minor diameter in r band (isoB_r)
633-639 F7.1 deg rPA ? Position angle of risoA in g band (isoPhi_r)
641-656 A16 --- iFlags [0-9A-F] Detection flags, i band (flags_i)(3)
658-658 I1 --- is [0-2] 0=notStar, 1=Star in i band (probPSF_i)
660-660 I1 --- ic [0,9] Phototype in i band, 6=Star (type_i) (1)
662-670 F9.4 yr iDate Date of observation in i band
672-677 F6.3 mag i'mag ? Model magnitude in i filter (= imag) (5)
679-684 F6.3 mag e_i'mag ? Mean error on i'mag (= e_imag)
686-691 F6.3 mag ipmag ? PSF magnitude in i band (psfMag_i)
693-698 F6.3 mag e_ipmag ? Mean error on ipmag (psfMagErr_i)
700-705 F6.3 mag iPmag ? Petrosian magnitude in i band (petroMag_i)
707-712 F6.3 mag e_iPmag ? Mean error on iPmag (petroMagErr_i)
714-720 F7.3 arcsec iPrad ? Petrosian radius in i band (petroMagErr_i)
722-728 F7.3 arcsec e_iPrad ? Mean error in iPrad (petroMagErr_i)
730-735 F6.2 arcsec ioRA ? Offset of i position along RA (offsetRa_i)
737-743 F7.2 arcsec ioDE ? Offset of i position along Dec (offsetDec_i)
745-753 F9.3 arcsec iisoA ? Isophotal major diameter in i band (isoA_i)
755-763 F9.3 arcsec iisoB ? Isophotal minor diameter in i band (isoB_i)
765-771 F7.1 deg iPA ? Position angle of iisoA in g band (isoPhi_i)
773-788 A16 --- zFlags [0-9A-F] Detection flags, z band (flags_z)(3)
790-790 I1 --- zs [0-2] 0=notStar, 1=Star in z band (probPSF_z)
792-792 I1 --- zc [0,9] Phototype in z band, 6=Star (type_z) (1)
794-802 F9.4 yr zDate Date of observation in z band
804-809 F6.3 mag z'mag ? Model magnitude in z filter (= zmag) (5)
811-816 F6.3 mag e_z'mag ? Mean error on z'mag (= e_zmag)
818-823 F6.3 mag zpmag ? PSF magnitude in z band (psfMag_z)
825-830 F6.3 mag e_zpmag ? Mean error on zpmag (psfMagErr_z)
832-837 F6.3 mag zPmag ? Petrosian magnitude in z band (petroMag_z)
839-844 F6.3 mag e_zPmag ? Mean error on zPmag (petroMagErr_z)
846-852 F7.3 arcsec zPrad ? Petrosian radius in z band (petroMagErr_z)
854-860 F7.3 arcsec e_zPrad ? Mean error in zPrad (petroMagErr_z)
862-867 F6.2 arcsec zoRA ? Offset of z position along RA (offsetRa_z)
869-875 F7.2 arcsec zoDE ? Offset of z position along Dec (offsetDec_z)
877-885 F9.3 arcsec zisoA ? Isophotal major diameter in z band (isoA_z)
887-895 F9.3 arcsec zisoB ? Isophotal minor diameter in z band (isoB_z)
897-903 F7.1 deg zPA ? Position angle of zisoA in g band (isoPhi_z)
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Note (1): the type (class) is numbered as follows:
0 = Unknown: Object type is not known.
1 = Cosmic-ray track (not used).
2 = Defect (not used)
3 = Galaxy: An extended object composed of many stars and other matter.
4 = Ghost: Object created by reflected or refracted light. (not used)
5 = KnownObject: Object came from some other catalog (not yet used)
6 = Star: A a self-luminous gaseous celestial body.
7 = Trail: A satellite or asteroid or meteor trail. (not yet used)
8 = Sky: Blank sky spectrogram (no objects in this arcsecond area).
9 = NotAType
Note (2): the SDSS identifier is composed of the skyVersion number,
run, rerun, camcol, field and object number. The SDSS-ID
is written run.cam.field.obj (4 numbers and 3 separator dots).
The objID is also combined from these numbers:
objID = skyVersion≪59 + rerun≪48 + run≪32
+ camcol≪29 + field≪16 + obj
Note (3): flags written in hexadecimal, full description available at
http://cas.sdss.org/astro/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.
1000000000000000 = OBJECT2DEBLENDPEEPHOLE Deblend modified by peephole
2000000000000000 = GROWN_MERGED Growing led to a merger
4000000000000000 = HAS_CENTER Object has a canonical center
8000000000000000 = RESERVED Not used
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Note (4): status flags written in hexadecimal, full description available at
http://cas.sdss.org/astro/en/help/browser/enum.asp?n=PhotoStatus
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00000001 = SET Object status has been set in reference to its own run
00000002 = GOOD Object is good -- absence implies bad.
00000004 = DUPLICATE Duplicate detections in an adjacent field
00000010 = OK_RUN Object is usable
00000020 = RESOLVED Object has been resolved against other runs.
00000040 = PSEGMENT Object Belongs to a PRIMARY segment.
00000100 = FIRST_FIELD Object belongs to the first field in its segment.
00000200 = OK_SCANLINE Object lies within valid nu range for its scanline.
00000400 = OK_STRIPE Object lies within valid eta range for its stripe.
00001000 = SECONDARY This is a secondary survey object.
00002000 = PRIMARY This is a primary survey object.
00004000 = TARGET This is a spectroscopic target.
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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/dr4/instruments/imager/index.html
The central wavelength and FWHM are:
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(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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History:
* 23-Oct-2024: format migration (CDS)
(End) Francois Ochsenbein [CDS] 27-Dec-2005