J/AJ/132/1796 Spectroscopy in nearby group cores (Carrasco+, 2006)
The dwarf galaxy population in nearby groups: the data.
Carrasco E.R., Mendes De Oliveira C., Infante L.
<Astron. J., 132, 1796-1817 (2006)>
=2006AJ....132.1796C 2006AJ....132.1796C
ADC_Keywords: Clusters, galaxy ; Radial velocities ; Photometry, CCD
Keywords: galaxies: clusters: general -
galaxies: clusters: individual (HCG 42, IC 4765, NGC 5846, NGC 6868) -
galaxies: dwarf - galaxies: fundamental parameters -
galaxies: photometry
Abstract:
We used V and I CCD photometry to search for low surface brightness
dwarf galaxies in the central (<0.5h-1Mpc) region of the groups
NGC 6868, NGC 5846, HCG 42, and the poor cluster IC 4765. We used
the exponential profile fit parameters to identify 80 low surface
brightness dwarf galaxy candidates with 17mag<V<22mag
(-16.7>MV>-11.4), V-I<1.5mag, µ0>22.5Vmag/arcsec2, h>1.5",
and diameters larger than 1.2h-1kpc. Twenty of these galaxies are
extended low surface brightness galaxies that were detected only on
smoothed images, after masking all high surface brightness objects.
The completeness in the sample detection is ∼80% for V~<20 and
22.5Vmag/arcsec2<µ0<24.5Vmag/arcsec2. For galaxies with
V>20mag and µ0>24.5Vmag/arcsec2, the completeness is below 50%
but increases to ∼80% when we search for galaxies in smoothed images.
Description:
The four groups studied were selected from the catalog of Garcia
(1993, Cat.J/A+AS/100/47). The groups vary in richness and density,
with galaxy populations that differ widely in morphological fractions.
Some of their characteristics are described below.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 57 4 Group parameters
table4.dat 102 474 Galaxy radial velocities
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See also:
J/A+AS/100/47 : Lyon Groups of Galaxies (Garcia 1993)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Group Group name
10- 11 I2 h RAh Right ascension (J2000)
13- 14 I2 min RAm Right ascension (J2000)
16- 19 F4.1 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign (J2000)
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 30 I2 arcsec DEs Declination (J2000)
32- 35 F4.1 Mpc Dist Assumed distance to HCG 42 (in h-1Mpc)
37- 39 I3 km/s sigma Velocity dispersion
41 A1 --- l_logLX [~] Limit flag on logLX
42- 46 F5.2 [10-7W] logLX X-ray luminosity (in h-2erg/s)
47 A1 --- r_logLX [bcd] logLX reference (1)
49- 52 F4.2 mag AV Absorption in V-band (2)
54- 57 F4.2 mag AI Absorption in I-band (2)
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Note (1): logLX reference as follows:
b = Mulchaey et al. (2003ApJS..145...39M 2003ApJS..145...39M)
c = Jones & Forman (1999, Cat. J/ApJ/511/65)
d = Beuing et al. (1999MNRAS.302..209B 1999MNRAS.302..209B)
Note (2): Absorption corrections determined from the reddening maps of
Schlegel et al. (1998ApJ...500..525S 1998ApJ...500..525S)
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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- 15 A15 --- [CMI2006b] Galaxy identification
17 A1 --- n_[CMI2006b] [a-d] Note on [CMI2006b] (1)
19- 20 I2 h RAh Hour of Right Ascension (J2000)
22- 23 I2 min RAm Minute of Right Ascension (J2000)
25- 28 F4.1 s RAs Second of Right Ascension (J2000)
30 A1 --- DE- Sign of the Declination (J2000)
31- 32 I2 deg DEd Degree of Declination (J2000)
34- 35 I2 arcmin DEm Arcminute of Declination (J2000)
37- 38 I2 arcsec DEs Arcsecond of Declination (J2000)
40- 44 F5.2 mag Vmag Total V band magnitude
46- 50 F5.2 mag V-I ? The 3" aperture (V-I) color index
52- 57 I6 km/s czh Heliocentric radial velocity
59- 61 I3 km/s e_czh The 1σ error in czh
63- 66 F4.1 --- R ? Tonry-Davis correlation value (6)
68- 69 I2 --- o_czh ? Number of lines used to calculate czh
71 I1 --- n_czh [0/1] value included for cz computation (2)
73- 78 I6 km/s cz Final radial velocity (3)
80- 82 I3 km/s e_cz The 1σ error in cz (4)
84- 88 A5 --- Ref References (5)
90-102 A13 --- Name Name of the galaxy in the reference
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Note (1): Note as follows:
a = Galaxy observed in two different masks
b = Background galaxy selected as LSBD
c = LSBD galaxy in the background of the group NGC 6868
d = LSBD galaxy member of the group
Note (2): For galaxies with multiple measurements:
0 = value has been discarded
1 = value has been included in the calculation of the final
radial velocity (cz)
Note (3): For galaxies with multiple measurements, these values are the
mean weighted velocity (see text).
Note (4): Error yielded by the RVSAO/RVIDLINE packages and by the error of
the weighted mean velocity in the case of multiple measurements.
Note (5): References as follows:
R96 = Ramella et al. (1996, Cat. J/A+A/312/745)
MKV92 = Malamuth et al. (1992AJ....104..495M 1992AJ....104..495M)
S96 = Stein (1996, Cat. J/A+AS/116/203)
G93 = Garcia (1993, Cat. J/A+AS/100/47)
ZM98 = Zabludoff & Mulchaey (1998, Cat. J/ApJ/496/39)
ZM00 = Zabludoff & Mulchaey (2000, Cat. J/ApJ/539/136)
dC97 = de Carvalho et al. (1997, Cat. J/ApJS/110/1)
NED = NASA/IPAC Extragalactic database (http://nedwww.ipac.caltech.edu/)
Note (6): Correlation from Tonry & Davis (1979AJ.....84.1511T 1979AJ.....84.1511T). For R>4,
the template that gave the lowest error was used to derive the radial
velocity, and for R≤4 line-by-line Gaussian fitting was used.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 26-Sep-2008