J/MNRAS/369/1375 Dwarf galaxies in NGC 1407 Group (Trentham+, 2006)
Dwarf galaxies in the dynamically evolved NGC 1407 Group.
Trentham N., Tully R.B., Mahdavi A.
<Mon. Not. R. Astron. Soc., 369, 1375-1391 (2006)>
=2006MNRAS.369.1375T 2006MNRAS.369.1375T
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Radial velocities
Keywords: galaxies: clusters: individual: NGC 1407 Group -
galaxies: luminosity function, mass function - galaxies: photometry
Abstract:
The NGC 1407 Group stands out among nearby structures by its
properties that suggest it is massive and evolved. It shares
properties with entities that have been called fossil groups: the 1.4m
differential between the dominant elliptical galaxy and the second
brightest galaxy comes close to satisfying the definition that has
been used to define the fossil class. There are few
intermediate-luminosity galaxies, but a large number of dwarfs in the
group. We estimate there are 250 group members to the depth of our
survey. The slope of the faint end of the luminosity function
(reaching MR=12) is alpha=-1.35. Velocities for 35 galaxies
demonstrate that this group with one dominant galaxy has a mass of
7x1013M☉ and M/LR=340M☉/L☉. Two galaxies in
close proximity to NGC 1407 have very large blueshifts. The most
notable is the second brightest galaxy, NGC 1400, with a velocity of
1072km/s with respect to the group mean. We report the detection of
X-ray emission from this galaxy and from the group.
Description:
Imaging observations were made with the CFHT 12 K CCD camera in queue
mode over six photometric nights between 2002 November 8 and
2002 December 6.
Spectroscopic observations were made using the blue side of the
Low-Resolution Imaging Spectrograph on the Keck I 10-m telescope, on
2003 November 27.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 98 268 The NGC 1407 Group sample
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See also:
J/MNRAS/335/712 : R magnitude of cluster of galaxies (Trentham+, 2002)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [TTM2006] Sequential number
5- 31 A27 --- Name Name
33- 37 A5 --- MType Morphological type
40 I1 --- Mm [0/5]? Rating that describes our assessment
of the membership probability (1)
41 A1 --- n_Mm [*] *: rated from Subaru data
43- 46 I4 km/s HV ? Heliocentric velocity
48- 49 I2 h RAh Right ascension (J2000)
51- 52 I2 min RAm Right ascension (J2000)
54- 58 F5.2 s RAs Right ascension (J2000)
60 A1 --- DE- Declination sign (J2000)
61- 62 I2 deg DEd Declination (J2000)
64- 65 I2 arcmin DEm Declination (J2000)
67- 68 I2 arcsec DEs Declination (J2000)
70- 74 F5.2 --- R300 ? Central surface brightness (luminosity in a
300pc=2.5arcsec radius aperture)
76- 80 F5.2 mag Rmag ? R magnitude
82- 87 F6.2 mag RMAG ? Absolute R magnitude
89- 90 I2 --- [TT2002] ? Identification number, [TT2002] NGC 1407 NN
in Simbad, from TT2 (2)
92 I1 --- MmT [0/4]? Membership code from TT2 (2) (3)
94- 98 F5.2 --- RmagT ? Total R apparent magnitude from TT2 (2)
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Note (1): Membership codes as follows:
0 = membership confirmed from optical or HI spectroscopic data
1 = probable member, but no spectroscopic or HI detection in the
literature
2 = possibly a member, but conceivably background
3 = plausibly a member
4 = passes ICP/OCP surface brightness test but almost certainly
background given the morphology of the galaxy and the properties
of the background fields studied at various stages during this project
5 = fails ICP/OCP surface brightness test. The vast majority (several
thousand with R<25) of galaxies were rated 5
Note (2): Data from Trentham & Tully, 2002, Cat. J/MNRAS/335/712
Note (3): Membership probability as follows:
0 = membership confirmed from optical spectroscopic or HI data
1 = probable member, but no spectroscopic or HI detection in the
literature
2 = possibly a member, but conceivably background
3 = probably background, but conceivably a member
4 = almost certainly background given the properties of the background
fields studied in Trentham et al., 2001MNRAS.325..385T 2001MNRAS.325..385T
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Jan-2007