J/ApJS/261/11 SMUDGes. III. The Southern catalog (Zaritsky+, 2022)
Systematically Measuring Ultra-Diffuse Galaxies (SMUDGes).
III. The Southern SMUDGes catalog.
Zaritsky D., Donnerstein R., Karunakaran A., Barbosa C.E., Dey A.,
Kadowaki J., Spekkens K., Zhang H.
<Astrophys. J. Suppl. Ser., 261, 11 (2022)>
=2022ApJS..261...11Z 2022ApJS..261...11Z
ADC_Keywords: Photometry, ugriz; Galaxy catalogs; Morphology; Extinction;
Surveys
Keywords: Low surface brightness galaxies ; Galaxy structure
Abstract:
We present a catalog of 5598 ultra-diffuse galaxy (UDG) candidates
with effective radius re>5.3" distributed throughout the southern
portion of the DESI Legacy Imaging Survey covering ∼15000deg2. The
catalog is most complete for physically large (re>2.5kpc) UDGs lying
in the redshift range 1800≲cz/km.s-1≲7000, where the lower bound
is defined by where incompleteness becomes significant for large
objects on the sky and the upper bound by our minimum angular size
selection criterion. Because physical size is integral to the
definition of a UDG, we develop a method of distance estimation using
existing redshift surveys. With three different galaxy samples, two of
which contain UDGs with spectroscopic redshifts, we estimate that the
method has a redshift accuracy of ∼75% when the method converges,
although larger, more representative spectroscopic UDG samples are
needed in order to fully understand the behavior of the method. We are
able to estimate distances for 1079 of our UDG candidates (19%).
Finally, to illustrate some uses of the catalog, we present both
distance-independent and distance-dependent results. In the latter
category, we establish that the red sequence of UDGs lies on the
extrapolation of the red sequence relation for bright ellipticals and
that the environment-color relation is at least qualitatively similar
to that of high surface brightness galaxies. Both of these results
challenge some of the models proposed for UDG evolution.
Description:
We report the results of our analysis of all images obtained with
DECam at the CTIO 4m, or Blanco telescope, which are included in Data
Release 9 (DR9) of the DESI Legacy Imaging Surveys
(Dey+ 2019AJ....157..168D 2019AJ....157..168D).
To keep our simulation pipeline identical to our science pipeline, we
include all 5760 candidates in our catalog, with those visually
identified as false positives flagged. See Section 4.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 365 5760 The catalog
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See also:
J/ApJS/225/11 : Subaru-UDGs in the Coma cluster (Yagi+, 2016)
J/ApJ/842/133 : HI-bearing ultra-diffuse ALFALFA galaxies (Leisman+, 2017)
J/ApJ/857/104 : Low surface brightness galaxies from HSC-SSP (Greco+, 2018)
J/ApJS/240/1 : SMUDGes. I. First results in the Coma Cluster (Zaritsky+, 2019)
J/ApJS/247/46 : Opt. phot. of SMUDGes ultra-diffuse galaxies (Barbosa+, 2020)
J/ApJ/923/257 : Ultra-diffuse gal. with spectroscopic obs. (Kadowaki+, 2021)
J/ApJS/252/18 : Low-surface-brightness galaxies from DES Y3 (Tanoglidis+, 2021)
J/ApJS/257/60 : SMUDGes. II. Expanded survey & Stripe 82 cat. (Zaritsky+, 2021)
http://www.legacysurvey.org/ : DESI Legacy Imaging Surveys home page
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SMDG]
5- 18 A14 --- SMDG Galaxy name in SMDG catalog
(HHMMSSs+DDMMSS; J2000)
20- 28 F9.5 deg RAdeg Right Ascension (J2000)
30- 38 F9.5 deg DEdeg [-65.6/34.8] Declination (J2000)
40- 45 F6.2 arcsec Re [5/125] Effective radius in angular
units
47- 52 F6.2 arcsec B_ReBias [-7.1/12]?=-99.99 The 1σ upper
limit in ReBias (1)
54- 59 F6.2 arcsec ReBias [-6.3/8.4]?=-99.99 Bias; angular;
corrected Re=Re-ReBias
61- 66 F6.2 arcsec b_ReBias [-1.3/20]?=-99.99 The 1σ lower
limit in ReBias (1)
68 I1 --- f_Re [0/1] Flag on Re: 0=good;
1=extrapolated
70- 73 F4.2 --- b/a [0.37/1] Minor to major axis ratio
75- 80 F6.2 --- B_b/aBias [-0.2/0.3]?=-99.99 The 1σ upper
limit in b/aBias (1)
82- 87 F6.2 --- b/aBias [-0.05/0.08]?=-99.99 Bias; corrected
b/a=b/a-b/aBias
89- 94 F6.2 --- b_b/aBias [-0.08/0.3]?=-99.99 The 1σ lower
limit in b/aBias (1)
96 I1 --- f_b/a [0/1] Flag on b/a: 0=good;
1=extrapolated
98- 101 F4.2 --- n [0.12/1.95] Sersic index
103- 108 F6.2 --- B_nBias [-0.02/1.2]?=-99.99 The 1σ upper
limit in nBias (1)
110- 115 F6.2 --- nBias [-0.6/0.6]?=-99.99 Bias; corrected
n=n-nBias
117- 122 F6.2 --- b_nBias [-0.5/0.7]?=-99.99 The 1σ lower
limit in nBias (1)
124 I1 --- f_n [0/1] Flag on n: 0=good;
1=extrapolated
126- 131 F6.2 deg PA [-90/90] Position angle of major axis
measured N to E
133- 138 F6.2 deg B_PABias [-12/58]?=-99.99 The 1σ upper
limit in PABias (1)
140- 145 F6.2 deg PABias [0]?=-99.99 Bias; corrected
PA=PA-PABias (always "0")
147- 152 F6.2 deg b_PABias [-98/55]?=-99.99 The 1σ lower
limit in PABias (1)
154 I1 --- f_PA [0/1] Flag on PA: 0=good;
1=extrapolated
156- 161 F6.2 mag/arcsec2 mu0g [24/28.96]?=-99.99 Central surface
brightness in g, AB mag (2)
163- 168 F6.2 mag/arcsec2 B_mu0gBias [-0.3/0.52]?=-99.99 The 1σ upper
limit in mu0gBias (1)
170- 175 F6.2 mag/arcsec2 mu0gBias [-0.4/0.64]?=-99.99 Bias; corrected
mu0g=mu0g-mu0gBias
177- 182 F6.2 mag/arcsec2 b_mu0gBias [0.03/1.52]?=-99.99 The 1σ lower
limit in mu0gBias (1)
184 I1 --- f_mu0g [0/1] Flag on mu0g: 0=good;
1=extrapolated
186- 191 F6.2 mag/arcsec2 mu0r [23/28.8]?=-99.99 Central surface
brightness in r, AB mag (2)
193- 198 F6.2 mag/arcsec2 B_mu0rBias [-0.15/0.7]?=-99.99 The 1σ upper
limit in mu0rBias (1)
200- 205 F6.2 mag/arcsec2 mu0rBias [-0.4/0.8]?=-99.99 Bias; corrected
mu0r=mu0r-mu0rBias
207- 212 F6.2 mag/arcsec2 b_mu0rBias [0.04/1.43]?=-99.99 The 1σ lower
limit in mu0rBias (1)
214 I1 --- f_mu0r [0/1] Flag on mu0r: 0=good;
1=extrapolated
216- 221 F6.2 mag/arcsec2 mu0z [13/27.43]?=-99.99 Central surface
brightness in z, AB mag (2)
223- 228 F6.2 mag/arcsec2 B_mu0zBias [-0.6/0.44]?=-99.99 The 1σ upper
limit in mu0zBias (1)
230- 235 F6.2 mag/arcsec2 mu0zBias [-0.12/0.95]?=-99.99 Bias; corrected
mu0z=mu0z-mu0zBias
237- 242 F6.2 mag/arcsec2 b_mu0zBias [0.03/1.58]?=-99.99 The 1σ lower
limit in mu0zBias (1)
244 I1 --- f_mu0z [0/1] Flag on mu0z: 0=good;
1=extrapolated
246- 251 F6.2 mag gmag [15.47/22.5]?=-99.99 Total apparent g
mag, AB mag (2)
253- 258 F6.2 mag B_gmagBias [-0.7/0.4]?=-99.99 The 1σ upper
limit in gmagBias (1)
260- 265 F6.2 mag gmagBias [-0.42/0.9]?=-99.99 Bias; corrected
gmag=mmag-gmagBias
267- 272 F6.2 mag b_gmagBias [-0.3/1.4]?=-99.99 The 1σ lower
limit in gmagBias (1)
274 I1 --- f_gmag [0/1] Flag on gmag: 0=good;
1=extrapolated
276- 281 F6.2 mag rmag [12.67/21.84]?=-99.99 Total apparent r
mag, AB mag (2)
283- 288 F6.2 mag B_rmagBias [-0.3/0.77]?=-99.99 The 1σ upper
limit in rmagBias (1)
290- 295 F6.2 mag rmagBias [-0.53/0.8]?=-99.99 Bias; corrected
rmag=rmag-rmagBias
297- 302 F6.2 mag b_rmagBias [-0.3/1.52]?=-99.99 The 1σ lower
limit in rmagBias (1)
304 I1 --- f_rmag [0/1] Flag on rmag: 0=good;
1=extrapolated
306- 311 F6.2 mag zmag [10.47/21.86]?=-99.99 Total apparent z
mag, AB mag (2)
313- 318 F6.2 mag B_zmagBias [-0.7/0.68]?=-99.99 The 1σ upper
limit in zmagBias (1)
320- 325 F6.2 mag zmagBias [-0.6/0.98]?=-99.99 Bias; corrected
zmag=zmag-zmagBias
327- 332 F6.2 mag b_zmagBias [-0.51/1.8]?=-99.99 The 1σ lower
limit in zmagBias (1)
334 I1 --- f_zmag [0/1] Flag on zmag: 0=good;
1=extrapolated
336 I1 --- VC [0/2] Visual classification; 0=good;
1=rejected (146 occurrences);
2=disagreement (16 occurrences)
338- 341 F4.2 --- SFD [0/0.07] Optical depth at location
from Schlegel+ maps for DECaLS filters
343- 346 F4.2 mag Ag [0.01/0.24] Corresponding extinction
in g band
348- 351 F4.2 mag Ar [0.01/0.16] Corresponding extinction
in r band
353- 356 F4.2 mag Az [0/0.09] Corresponding extinction in z
band
358- 363 F6.2 --- comp [-0.33/0.58]?=-99.99 Fractional
completeness
365 I1 --- f_comp [0/2] Flag on comp: 0=good,
1=extrapolated completness, 2=biases
extrapolated
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Note (1): Uncertainties bounds are to be applied relative to the
measured value but describe the bias-corrected uncertainty interval.
Note (2): Magnitudes not extinction corrected.
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History:
From electronic version of the journal
References:
Zaritsky et al. Paper I. 2019ApJS..240....1Z 2019ApJS..240....1Z Cat. J/ApJS/240/1
Zaritsky et al. Paper II. 2021ApJS..257...60Z 2021ApJS..257...60Z Cat. J/ApJS/257/60
Zaritsky et al. Paper III. 2022ApJS..261...11Z 2022ApJS..261...11Z This catalog
Zaritsky et al. Paper V. 2023ApJS..267...27Z 2023ApJS..267...27Z Cat. J/ApJS/267/27
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 21-Sep-2022