J/AJ/127/704 Low surface brightness galaxies in SDSS (Kniazev+, 2004)
Low surface brightness galaxies in the Sloan Digital Sky Survey.
I. Search method and test sample.
Kniazev A.Y., Grebel E.K., Pustilnik S.A., Pramskij A.G., Kniazeva T.F.,
Prada F., Harbeck D.
<Astron. J., 127, 704-727 (2004)>
=2004AJ....127..704K 2004AJ....127..704K
ADC_Keywords: Galaxies, photometry ; Photometry, SDSS ; Photometry, surface
Keywords: galaxies: fundamental parameters - galaxies: irregular -
galaxies: photometry - galaxies: spiral - galaxies: structure -
methods: data analysis
Abstract:
In this paper we present results of a pilot study to use imaging data
from the Sloan Digital Sky Survey (SDSS) to search for low surface
brightness (LSB) galaxies. For our pilot study we use a test sample of
92 galaxies from the Impey et al. catalog distributed over 93 SDSS
fields of the Early Data Release (EDR, J/AJ/123/567). Many galaxies
from the test sample are either LSB or dwarf galaxies. To deal with
the SDSS data most effectively, a new photometry software was created,
which is described in this paper. We present the results of the
selection algorithms applied to these 93 EDR fields. Two galaxies from
the Impey et al. (1996, J/ApJS/105/209) test sample are very likely
artifacts, as confirmed by follow-up imaging. With our algorithms we
were able to recover 87 of the 90 remaining test sample galaxies,
implying a detection rate of ∼96.5%. The three missed galaxies fall
too close to very bright stars or galaxies. In addition, 42 new
galaxies with parameters similar to the test sample objects were found
in these EDR fields (i.e.,∼47% additional galaxies). We present the
main photometric parameters of all identified galaxies and carry out
first statistical comparisons. We tested the quality of our photometry
by comparing the magnitudes for our test sample galaxies and other
bright galaxies with values from the literature. All these tests
yielded consistent results. We briefly discuss a few unusual galaxies
found in our pilot study, including an LSB galaxy with a two-component
disk and 10 new giant LSB galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 124 129 The general parameters of large-angular-size
galaxies identified in the fields of the
test subsample
table2.dat 108 129 Total magnitudes and model-independent parameters
of large-angular-size galaxies identified in the
test fields
table3.dat 144 110 Model-dependent photometric parameters of
large-angular-size galaxies identified in the
test fields
table4.dat 110 14 Model-dependent photometric parameters of
large-angular-size galaxies with Sersic profiles
identified in the test fields
table5.dat 74 6 The photometric repeatability
table6.dat 54 11 Giant LSB spiral galaxies from our sample
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See also:
J/AJ/123/567 : SDSS quasar catalog, I: Early Data Release (Schneider+, 2002)
J/ApJS/105/209 : Low surface brightness galaxies. I. The catalog (Impey+ 1996)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Running identification number
5- 8 A4 --- --- [SDSS]
10- 23 A14 --- SDSS SDSS name (1)
25- 33 A9 --- ISI96 Impey et al. (1996, J/ApJS/105/209) name (2)
35- 36 I2 h RAh Hour of Right Ascension (J2000)
38- 39 I2 min RAm Minute of Right Ascension (J2000)
41- 45 F5.2 s RAs Second of Right Ascension (J2000)
47 A1 --- DE- Sign of the Declination (J2000)
48- 49 I2 deg DEd Degree of Declination (J2000)
51- 52 I2 arcmin DEm Arcminute of Declination (J2000)
54- 58 F5.2 arcsec DEs Arcsecond of Declination (J2000)
60- 62 I3 --- SDSSrun SDSS image run number
64 I1 --- SDSScol SDSS image column
66- 68 I3 --- SDSSfield SDSS image field
70- 74 F5.2 mag Bmag Apparent B band magnitude (3)
76- 79 F4.2 mag e_Bmag Error in Bmag (3)
81- 84 F4.2 mag B-V (B-V) color (4)
86- 91 F6.2 mag BMAG ? Absolute B band magnitude (5)
93- 97 I5 km/s HRV ? Heliocentric velocity (6)
99-104 A6 --- MType Morphological classification (7)
106-123 A18 --- OName Other NED names
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Note (1): Based on the equatorial coordinates for equinox J2000.
Note (2): If not from Impey et al. (1996, J/ApJS/105/209),
this entry is blank.
Note (3): Recalculated from g* and r* integrated magnitudes using of
equations from Smith et al. (2002AJ....123.2121S 2002AJ....123.2121S).
Note (4): Calculated from g* and r* magnitudes using the respective
equations from Smith et al. (2002AJ....123.2121S 2002AJ....123.2121S).
Note (5): Calculated from Bmag in the previous column and the distance derived
from the known heliocentric velocities, assuming a Hubble flow with
H0=75km/s/Mpc, with no corrections for the motion of the Sun
and Local Group. No corrections have been made for Galactic
foreground extinction.
Note (6): Taken from Impey et al. (1996, J/ApJS/105/209), from the SDSS EDR
(J/AJ/123/567) database and the NASA/IPAC Extragalactic Database (NED)
Note (7): In the system of de Vaucouleurs et al. (1991, VII/155). This
classification was based on that suggested in Impey et al. (1996,
J/ApJS/105/209) and NED, where applicable. However, accounting for
the superb quality of the SDSS images relative to most of the
previously available data, we have checked the classification for all
sample galaxies and revised it in a number of cases. For the
remaining galaxies the classification was also done by the authors.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Running identification number
5- 8 A4 --- --- [SDSS]
10- 23 A14 --- SDSS SDSS name (G1)
25- 29 F5.2 mag u*mag ? SDSS u* band integrated magnitude
31- 34 F4.2 mag e_u*mag ? Error in u*mag
36- 40 F5.2 mag g*mag SDSS g* band integrated magnitude
42- 45 F4.2 mag e_g*mag Error in g*mag
47- 51 F5.2 mag r*mag SDSS r* band integrated magnitude
53- 56 F4.2 mag e_r*mag Error in r*mag
58- 62 F5.2 mag i*mag SDSS i* band integrated magnitude
64- 67 F4.2 mag e_i*mag Error in i*mag
69- 73 F5.2 mag z*mag SDSS z* band integrated magnitude
75- 78 F4.2 mag e_z*mag Error in z*mag
80- 83 F4.2 --- b/a Axis ratio
85- 87 I3 deg PA [-90/90] Position angle
89- 92 F4.1 arcsec Reff r band effective radius
94- 97 F4.1 mag/arcsec2 mueff(r) r band mean surface brightness inside Reff
99-101 F3.1 --- CI r band concentration index
103-107 F5.1 arcsec A26.2 r band size at SB=26.2mag/arcsec2
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- SDSS SDSS name (G1)
16- 20 F5.2 mag/arcsec2 mu0d(g*) g* band disk surface brightness
22- 25 F4.2 mag/arcsec2 e_mu0d(g*) Error in mu0d(g*)
27- 31 F5.2 arcsec alphad(g*) g* band disk scale length
33- 36 F4.2 arcsec e_alphad(g*) Error in alphad(g*)
38- 42 F5.2 mag/arcsec2 mu0b(g*) ? g* band bulge surface brightness
44- 47 F4.2 mag/arcsec2 e_mu0b(g*) ? Error in mu0b(g*)
49- 52 F4.2 arcsec alphab(g*) ? g* band bulge scale length
54- 57 F4.2 arcsec e_alphab(g*) ? Error in alphab(g*)
59- 63 F5.2 mag/arcsec2 mu0d(r*) r* band disk surface brightness
65- 68 F4.2 mag/arcsec2 e_mu0d(r*) Error in mu0d(r*)
70- 74 F5.2 arcsec alphad(r*) r* band disk scale length
76- 79 F4.2 arcsec e_alphad(r*) Error in alphad(r*)
81- 85 F5.2 mag/arcsec2 mu0b(r*) ? r* band bulge surface brightness
87- 90 F4.2 mag/arcsec2 e_mu0b(r*) ? Error in mu0b(r*)
92- 95 F4.2 arcsec alphab(r*) ? r* band bulge scale length
97-100 F4.2 arcsec e_alphab(r*) ? Error in alphab(r*)
102-106 F5.2 mag/arcsec2 mu0d(i*) i* band disk surface brightness
108-111 F4.2 mag/arcsec2 e_mu0d(i*) Error in mu0d(i*)
113-117 F5.2 arcsec alphad(i*) i* band disk scale length
119-122 F4.2 arcsec e_alphad(i*) Error in alphad(i*)
124-128 F5.2 mag/arcsec2 mu0b(i*) ? i* band bulge surface brightness
130-133 F4.2 mag/arcsec2 e_mu0b(i*) ? Error in mu0b(i*)
135-138 F4.2 arcsec alphab(i*) ? i* band bulge scale length
140-143 F4.2 arcsec e_alphab(i*) ? Error in alphab(i*)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- SDSS SDSS name (G1)
16- 20 F5.2 mag/arcsec2 mu0(g*) g* band surface brightness
22- 25 F4.2 mag/arcsec2 e_mu0(g*) rms uncertainty on mu0(g*)
27- 31 F5.2 arcsec alpha(g*) g* band scale length
33- 36 F4.2 arcsec e_alpha(g*) rms uncertainty on alpha(g*)
38- 41 F4.2 --- n(g*) g* band Sersic number
43- 46 F4.2 --- e_n(g*) rms uncertainty on n(g*)
48- 52 F5.2 mag/arcsec2 mu0(r*) r* band surface brightness
54- 57 F4.2 mag/arcsec2 e_mu0(r*) rms uncertainty on mu0(r*)
59- 63 F5.2 arcsec alpha(r*) r* band scale length
65- 68 F4.2 arcsec e_alpha(r*) rms uncertainty on alpha(r*)
70- 73 F4.2 --- n(r*) r* band Sersic number
75- 78 F4.2 --- e_n(r*) rms uncertainty on n(r*)
80- 84 F5.2 mag/arcsec2 mu0(i*) i* band surface brightness
86- 89 F4.2 mag/arcsec2 e_mu0(i*) rms uncertainty on mu0(i*)
91- 95 F5.2 arcsec alpha(i*) i* band scale length
97-100 F4.2 arcsec e_alpha(i*) rms uncertainty on alpha(i*)
102-105 F4.2 --- n(i*) i* band Sersic number
107-110 F4.2 --- e_n(i*) rms uncertainty on n(i*)
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
6- 19 A14 --- SDSS SDSS name (G1)
21- 25 F5.2 mag u*mag u* magnitude
27- 30 F4.2 mag e_u*mag rms uncertainty on u*mag
32- 36 F5.2 mag g*mag g* magnitude
38- 41 F4.2 mag e_g*mag rms uncertainty on g*mag
43- 47 F5.2 mag r*mag r* magnitude
49- 52 F4.2 mag e_r*mag rms uncertainty on r*mag
54- 58 F5.2 mag i*mag i* magnitude
60- 63 F4.2 mag e_i*mag rms uncertainty on i*mag
65- 69 F5.2 mag z*mag z* magnitude
71- 74 F4.2 mag e_z*mag rms uncertainty on u*mag
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
6- 19 A14 --- SDSS SDSS name (G1)
21- 29 A9 --- ISI96 Impey et al. (1996, J/ApJS/105/209) name
31- 36 F6.2 mag BMAGd Disk absolute B magnitude
38- 42 F5.2 mag/arcsec2 mu0c(B) Central Surface brightness in B band
44- 48 F5.2 kpc alpha Scale length
50- 54 F5.2 --- DIndex Diffuseness index [mu0c(B)+5log(alpha)]
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Global notes:
Note (G1): Based on the equatorial coordinates for equinox J2000.
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History:
* 19-May-2004: from electronic version of the journal
* 25-Mar-2006: table1, records #72 and 98, column OName:
VV635 is a misprint for VV 655, UGC8784 is a misprint for UGC8474
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 19-May-2004