J/ApJS/186/427 Detailed morphology of SDSS galaxies (Nair+, 2010)
A catalog of detailed visual morphological classifications for 14,034 galaxies
in the Sloan Digital Sky Survey.
Nair P.B., Abraham R.G.
<Astrophys. J. Suppl. Ser., 186, 427-456 (2010)>
=2010ApJS..186..427N 2010ApJS..186..427N
ADC_Keywords: Galaxy catalogs ; Morphology ; Photometry, SDSS ; Redshifts
Keywords: catalogs - galaxies: fundamental parameters - galaxies: photometry
galaxies: structure
Abstract:
We present a catalog of detailed visual classifications for 14034
galaxies in the Sloan Digital Sky Survey (SDSS) Data Release 4 (DR4,
Cat. II/267). Our sample includes nearly all spectroscopically
targeted galaxies in the redshift range 0.01<z<0.1 down to an apparent
extinction-corrected limit of g<16mag. In addition to T-Types, we
record the existence of bars, rings, lenses, tails, warps, dust lanes,
arm flocculence, and multiplicity. This sample defines a comprehensive
local galaxy sample which we will use in future papers to study
low-redshift morphology. It will also prove useful for calibrating
automated galaxy classification algorithms. In this paper, we describe
the classification methodology used, detail the systematics and biases
of our sample, and summarize the overall statistical properties of the
sample, noting the most obvious trends that are relevant for general
comparisons of our catalog with previously published work.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 421 14034 T-Type classification schemes
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See also:
VII/155 : Bright Galaxies Third Reference (RC3) (de Vaucouleurs+ 1991)
II/294 : SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/AJ/134/579 : SDSS DR3 Morphologically classified galaxies (Fukugita+, 2007)
J/AJ/128/163 : Galaxy morphological classification (Lotz+, 2004)
http://sdss.physics.nyu.edu/vagc/ : The NYU Value-Added Galaxy catalog site
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- SDSS SDSS name (JHHMMSS.ss+DDMMSS.ss)
22- 28 F7.3 deg RAdeg Right Ascension in decimal degrees, J2000
29- 30 A2 --- --- [0 ]
32- 38 F7.3 deg DEdeg Declination in decimal degrees, J2000
39- 40 A2 --- --- [0 ]
42- 46 F5.3 --- zs Spectroscopic redshift
47- 48 A2 --- --- [0 ]
50- 54 F5.3 --- q_zs [0.301/1] Confidence level in zs
56- 61 F6.3 mag g'mag ?=99. SDSS g' band magnitude;
extinction corrected
63- 68 F6.3 mag r'mag SDSS r' band magnitude;
extinction corrected
70- 76 F7.3 mag g'MAG ?=999. Absolute SDSS g' band magnitude (1)
78- 83 F6.3 [solLum] logLg' ?=99. Log of SDSS g' band luminosity
85- 90 F6.3 kpc Rp Petrosian radius
(Petrosian, 1976ApJ...209L...1P 1976ApJ...209L...1P)
91 A1 --- --- [0 ]
93- 99 F7.4 kpc Rp50 ?=99. Petrosian half light radius from SDSS
101-106 F6.3 kpc Rp90 ?=99. Petrosian 90% light radius from SDSS
108-121 A14 --- spID SDSS spectra ID (Plate-MJD-Fiber)
123-128 F6.3 [solMass] log(M) ?=99. Log of the mass (Kauffmann et
al., 2003MNRAS.341...33K 2003MNRAS.341...33K)
130-135 F6.3 Gyr Age ?=99. Age (Kauffmann et al.,
2003MNRAS.341...33K 2003MNRAS.341...33K)
136 A1 --- --- [0 ]
138-143 F6.3 mag g'-r' ?=99. SDSS (g'-r') color index
144-145 A2 --- --- [0 ]
147-153 F7.3 solMass/yr SFRT ?=999. Total star formation rate (2)
154-155 A2 --- --- [0 ]
157-163 F7.3 yr-1 SFRM ?=999. Total star formation rate per unit
mass (solMass/yr/solMass) (2)
165-170 F6.3 mag/arcsec2 mug Surface brightness in g band (3)
172-178 F7.3 solMass/kpc2 muM ?=999. Surface mass density
180-185 F6.3 Sun M/L ?=99. Mass to light ratio in g band
186-187 A2 --- --- [0 ]
189-195 F7.3 arcsec2 Area ?=999. Galaxy area
197-201 F5.3 --- b/a ?=9. Axis ratio
202-203 A2 --- --- [0 ]
205-208 F4.2 arcsec Seeing Seeing in g band
209 A1 --- --- [0 ]
214-220 I7 --- NYU-ID Object tag from NYU database (4)
224-228 F5.3 --- ng Single component Sersic g band index (5)
229 A1 --- --- [0 ]
231-235 F5.3 --- nr Single component Sersic r band index (5)
237-245 F9.3 --- chi2g The χ2 for ng (6)
247-255 F9.3 --- chi2r The χ2 for nr (6)
257-262 F6.3 --- R50n Single component Sersic g band half
light radius (5)
263-264 A2 --- --- [0 ]
265-270 F6.3 --- R90n Single component Sersic g band 90%
light radius (5)
272-278 F7.3 km/s sigma ?=600 SDSS velocity dispersion
280-286 F7.3 km/s e_sigma ?=-3 Error in sigma
288-292 F5.3 --- V/Vmax Maximum physical volume in which a
galaxy can be detected in DR4 (7)
293-294 A2 --- --- [0 ]
296 I1 --- AGN1 [0/3]?=9 AGN type using Kauffmann et al.
2003MNRAS.346.1055K 2003MNRAS.346.1055K, demarcation (8)
298 I1 --- AGN2 [0/3]?=9 AGN type using Kewley et al.,
2001ApJ...556..121K 2001ApJ...556..121K, demarcation (8)
300-305 I6 --- GrID ?=999999 Group ID from Yang et al.,
2007ApJ...671..153Y 2007ApJ...671..153Y (YA07) (9)
307-309 I3 --- Ngr ?=999 Number of galaxies group (in YA07)
311 I1 --- BiG ?=9 Flag indicating if galaxy is
most massive in group YA07 (10)
313 I1 --- LiG ?=9 Flag indicating if galaxy is
most luminous in group YA07 (10)
315-320 F6.3 [solLum] log(Lgr) ?=99 YA07 group log luminosity
322-327 F6.3 [solMass] log(Mgr) ?=99 YA07 group log mass
329-334 F6.3 [solMass] log(Mh1) ?=99 YA07 group halo mass estimate
336-341 F6.3 [solMass] log(Mh2) ?=99 YA07 group halo mass estimate
343-348 F6.3 --- rhoNYU ?=99 Environmental over-density (11)
350-355 F6.3 --- ?=99 Average environmental
over-density (12)
356-357 A2 --- --- [0 ]
359-364 F6.3 --- rho4 ?=99 4th neareast neighbor
environment estimate (13)
365-366 A2 --- --- [0 ]
368-373 F6.3 --- rho5 ?=99 5th neareast neighbor
environment estimate (13)
374-375 A2 --- --- [0 ]
377-378 I2 --- TT ?=99 T-Type classification using the
modified RC3 classifiers
380-381 I2 --- Bar Bar type (14)
383-385 I3 --- Ring Ring type (15)
387-388 I2 --- f_Ring Ring flag (16)
390-391 I2 --- Lens Lens Type (17)
393 I1 --- TTq T-Type flag (18)
395-396 I2 --- Pair Pair flag (19)
398-400 I3 --- f_Pair Pair type flag (20)
402-405 I4 --- Int Interaction type (21)
407-408 I2 --- Nt Number of tails (22)
410-416 A7 --- RC3 Full visual RC3 classification
418-421 F4.1 --- Tt ?=99. Fukugita et al., 2007,
Cat. J/AJ/134/579 Tt classification
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Note (1): Corrected to z=0 using the kcorrect code of Blanton et al.,
2007AJ....133..734B 2007AJ....133..734B
Note (2): Brinchmann et al., 2004MNRAS.351.1151B 2004MNRAS.351.1151B
Note (3): Corrected for galactic extinction and internal extinction as
prescribed by RC3, Cat. VII/155.
Note (4): From the NYU value added galaxy catalog (VAGC) for the DR4
release (Blanton et al., 2005AJ....129.2562B 2005AJ....129.2562B; recent version at
http://sdss.physics.nyu.edu/vagc/). This is provided to aid catalog
matching with the NYU database.
Note (5): Calculated by NYU-VAGC group (Blanton et al.,
2005AJ....129.2562B 2005AJ....129.2562B, 2003ApJ...594..186B 2003ApJ...594..186B).
Note (6): Calculated by NYU-VAGC group (Blanton et al., 2003ApJ...594..186B 2003ApJ...594..186B)
Note (7): Vmax is the maximum physical volume in which each galaxy can be
detected in the SDSS DR4 survey (which depends on the absolute
magnitude of the galaxy, its physical size, and its surface
brightness). However, in most cases our Vmax is defined by our upper
redshift limit of 0.1 rather than by the detection limit. V is the
volume the galaxy was detected in.
Note (8): Flags as follows:
0 = Star forming galaxy for AGN1; not AGN for AGN2
1 = Transition/mixed AGN,
2 = Seyfert only,
3 = LINER only.
Note (9): Briefly, Yang et al. (2007ApJ...671..153Y 2007ApJ...671..153Y) use an iterative
halo-based group finder on the NYU-VAGC SDSS catalog identifying
tentative group members using a modified friends-of-friends algorithm.
The group members were used to determine the group center, size, mass,
and velocity dispersion. New group memberships were determined
iteratively based on the halo properties.
Note (10): Flag as follows:
1 = most massive/luminous galaxy.
2 = satellite galaxy.
It is important to note that groups with only 1 member have the
luminous galaxy flag set (see Yang et al., 2007ApJ...671..153Y 2007ApJ...671..153Y).
Note (11): Estimated by NYU-VAGC group (Hogg et al., 2004ApJ...601L..29H 2004ApJ...601L..29H;
Blanton et al., 2005ApJ...629..143B 2005ApJ...629..143B). For each galaxy, neighbors
within a cylinder of 1h-1Mpc and a comoving half-length of 8h-1
are counted and the results divided by the mean predicted from the
luminosity function' (Blanton et al., 2003ApJ...592..819B 2003ApJ...592..819B).
Note (12): It is defined as Σ=N/(πdN2), where dN is the
projected comoving distance (in Mpc) to the Nth nearest neighbour
(within ±1000km/s if a spectroscopic redshift was available or
else with photometric redshift errors within the 95 percent confidence
limit). A best estimate density (to account for spectroscopic
incompleteness) was obtained by calculating the average density for
N=4 and N=5 with spectroscopically confirmed members only and with
the entire sample.
Note (13): From Baldry et al. (2006MNRAS.373..469B 2006MNRAS.373..469B).
Note (14): Encoded as {Sum}2i where i flags the following possible values:
1 = strong bar,
2 = intermediate,
3 = weak bar,
4 = ansae,
5 = peanut,
6 = nuclear bar
7 = bar unsure.
Thus if a large scale strong bar and a nuclear bar is present the bar
type will be 21+26=66.
Note (15): Encoded as {Sum}2i where i flags the following possible values:
1 = nuclear ring,
2 = inner ring,
3 = outer ring.
Note (16): Encoded as {Sum}2i where i flags the following possible values:
1 = partial ring,
2 = pseudo outer ring R1,
3 = pseudo outer ring R2.
Note (17): Encoded as {Sum}2i where i flags the following possible values:
1 = inner lens is present,
2 = outer lens is present.
Note (18): T-Type flags as follows:
0 = No flag set,
1 = Doubtful,
2 = Highly Doubtful,
3 = Unknown,
4 = peculiar.
Note (19): Encoded as {Sum}2i where i flags the following possible values:
1 = Close Pair,
2 = Projected Pair,
3 = Adjacent Pair,
4 = Overlapping Pair.
Note (20): Encoded as {Sum}2i where i flags the following possible values:
1 = Star,
2 = Compact object (small spheroid like),
3 = small fuzzy blob (morphology unclear),
4 = Elliptical/S0 galaxy,
5 = Disk galaxy,
6 = Irregular/Peculiar galaxy.
Note (21): Encoded as {Sum}2i where i flags the following possible values:
1 = No Interaction Signature,
2 = Disturbed,
3 = Warp,
4 = Shells,
5 = Short Tail,
6 = Medium Tail,
7 = Long Tail,
8 = Bridge.
Note (22): 1 Tail, 2 Tails, 3+Tails, Bunny.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 22-Apr-2010