J/A+A/479/1 Redshifts and morphology in A3667 (Johnston-Hollitt+, 2008)
The optical morphology of A3667 re-examined.
Johnston-Hollitt M., Hunstead R.W., Corbett E.
<Astron. Astrophys. 479, 1 (2008)>
=2008A&A...479....1J 2008A&A...479....1J
ADC_Keywords: Clusters, galaxy ; Galaxies, optical ; Spectroscopy ; Redshifts
Keywords: galaxies: clusters -
galaxies: distances and redshifts -
cosmology: large-scale structure of Universe
Abstract:
The galaxy cluster A3667 was observed using the Two-degree Field (2dF)
multifibre spectroscopic system on the Anglo-Australian Telescope in
a program designed to examine the velocity structure in the region.
Specifically, we sought evidence from the optical data for the putative
cluster merger believed to be responsible for the observed radio and
X-ray emission. We present 184 new redshifts in the region, of which
143 correspond to member galaxies of A3667. We find the cluster
velocity distribution to be well modelled by a single Gaussian in
agreement with previous results. In addition, new redshift-selected
isodensity plots significantly reduce the prominence of the previously
reported subgroup to the north-west of the main cluster. Instead, we
find the galaxy distribution to be elongated and well mixed, with a high
velocity dispersion and no significant evidence for substructure. These
results are consistent with the axis of the proposed merger being close
to the plane of the sky.
Description:
Spectroscopic redshifts for 143 galaxies found in the cluster A3667
and falling in the redshift range 0.044<z<0.068. For each galaxy we
give the catalogue ID, Right ascension and Declination in J2000
coordinates, the blue magnitude, the redshift determined by
absorption, the redshift determined by emission, the average redshift
between absorption and emission features, any previously published
spectroscopic redshift value and finally the morphological type
determined by the best correlation to the spectral templates listed in
Colless et al. (2001MNRAS.328.1039C 2001MNRAS.328.1039C).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 63 143 Spectroscopic parameters for 143 galaxies in A3667
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See also:
J/MNRAS/259/233 : Cluster SC2008-57(A3667) (Sodre+ 1992)
VII/250 : The 2dF Galaxy Redshift Survey (2dFGRS) (2dFGRS Team, 1998-2003)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- ID Source identification number used in paper
5- 6 I2 h RAh Right ascension (J2000.0)
8- 9 I2 min RAm Right ascension (J2000.0)
11- 15 F5.2 s RAs Right ascension (J2000.0)
17 A1 --- DE- Declination sign (J2000.0)
18- 19 I2 deg DEd Declination (J2000.0)
21- 22 I2 arcmin DEm Declination (J2000.0)
24- 27 F4.1 arcsec DEs Declination (J2000.0)
29- 33 F5.2 --- Bmag Blue magnitude
35- 40 F6.4 --- z(abs) ? Redshift determined by absorption features
42- 47 F6.4 --- z(em) ? Redshift determined by emission features
49- 54 F6.4 --- z(ave) ? Average redshift between z(abs) & z(em)
56- 61 F6.4 --- z(lit) ? Previously published redshift
63 I1 --- Type [1,5] Morphological Type: See Note (1)
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Note (1): This is the morphological type as determined by the best
correlation to the spectral templates listed in Colless et al.
(2001MNRAS.328.1039C 2001MNRAS.328.1039C): 1=E 2=cD 3=Sbc 4=Sc 5=Sm/Ir
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Acknowledgements:
Melanie Johnston-Hollitt <Melanie.JohnstonHollitt(at)gmail.com>
(End) Melanie Johnston-Hollitt [University of Tasmania] 20-Aug-2008