J/MNRAS/418/2054 Recession velocities for fossil galaxy groups (Proctor+, 2011)
On the mass-to-light ratios of fossil groups. Are they simply dark clusters?
Proctor R.N., Mendes De Oliveira C., Dupke R., Lopes De Oliveira R.,
Cypriano E.S., Miller E.D., Rykoff E.
<Mon. Not. R. Astron. Soc., 418, 2054-2073 (2011)>
=2011MNRAS.418.2054P 2011MNRAS.418.2054P
ADC_Keywords: Clusters, galaxy ; Radial velocities ; Photometry, SDSS
Keywords: galaxies: clusters: general - galaxies: groups: general -
X-rays: galaxies: clusters
Abstract:
Defined as X-ray bright galaxy groups with large differences between
the luminosities of their brightest and second brightest galaxies,
"fossil groups" are believed to be some of the oldest galaxy
systems in the Universe. They have therefore been the subject of much
recent research.
In this work we present a study of 10 fossil group candidates with an
average of 33 spectroscopically confirmed members per group, making
this the deepest study of its type to date. We also use these data to
perform an analysis of the luminosity function of our sample of fossil
groups.
Description:
The Magellan Baade telescope multi-object spectroscopy of five
candidate fossil groups selected from the maxBCG catalogue was carried
out on the f/2 camera of the IMACS instrument in 2009 February.
The Gemini GMOS spectroscopic observations of RX J1256.0+2556 were
carried out on Gemini North on 2006 June 24. Observations of
RX J1331.5+1108 were carried out on Gemini North on 2005 March 7.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 58 10 Group properties
tableb.dat 65 307 *Recession velocity and apparent magnitudes
for systems with new data
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Note on tableb.dat: Galaxies are identified as
<[PMD2011] JHHMMSS.ss+DDMMSS.s> in Simbad.
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Group name (1)
17- 22 F6.4 --- z Redshift
24 A1 --- l_logLx Limit flag on logLx
25- 29 F5.2 [10-7W] logLx Log of X-ray luminosity (2)
31- 34 F4.2 keV kTx ? X-ray temperature (2)
36- 39 F4.2 Mpc R200S R200 used in the selection of the target
systems
41- 44 F4.2 Mpc R200X R200 derived from the X-ray data (3)
45 A1 --- f_R200X [*] Flag for SDSS J0906+0301 (4)
47- 51 F5.2 [Msun] logM200X Mass (5)
52 A1 --- f_logM200X [*] Flag for SDSS J0906+0301 (4)
54- 57 F4.2 [Msun] e_logM200X logM200X uncertainty
58 A1 --- felogM200X [*] Flag for SDSS J0906+0301 (4)
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Note (1): For groups with prefix SDSS (the SDSS sample), X-ray data are the
Chandra data of Miller et al. (2012ApJ...747...94M 2012ApJ...747...94M). For the systems
in the RXJ sample the Chandra data of Khosroshahi et al.
(2007MNRAS.377..595K 2007MNRAS.377..595K) are presented.
Note (2): X-ray luminosities and temperatures are specified for an aperture
equal in size to R200.
Note (3): R200,X was calculated from the X-ray temperature using equation (2).
Note (4): For SDSS J0906+0301, which was undetected in the X-ray, the R200,X
is assumed to be 1.0Mpc based on its dynamical properties
(see Section 5.2).
Note (5): Group masses derived using equation (3).
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Byte-by-byte Description of file: tableb.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Group name (1)
17 A1 --- Ref [MGS] Source of spectroscopic data (2)
19- 20 I2 h RAh Right ascension (J2000)
22- 23 I2 min RAm Right ascension (J2000)
25- 29 F5.2 s RAs Right ascension (J2000)
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 41 F4.1 arcsec DEs Declination (J2000)
43- 47 I5 km/s RV Recession velocity (0 for the BCG galaxy)
49- 53 F5.2 mag gmag ?=- g magnitude
55- 59 F5.2 mag rmag ?=- r magnitude
61- 65 F5.2 mag imag ?=- i magnitude
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Note (1): Studied groups are SDSS J0906+0301, SDSS J1045+0420, SDSS J1136+0713,
SDSS J0856+0553, SDSS J1017+0156, RX J1256.0+2556 and RX J1331.5+1108.
Note (2): Source of spectroscopic data used to derive recession velocities
as follows:
M = Magellan telescope
G = Gemini telescope
S = SDSS database
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 16-Nov-2012