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Notes for object ABELL 2634

6 note(s) found in NED.


1. 2005ApJ...622..187M
Re:ABELL 2634
5.6. A2634
The XMM-Newton observation of A2634 was plagued by long periods of
high X-ray background, which did not allow us to extract as much
spectroscopic information as would have otherwise been possible for
this bright cluster. The radio source 3C 465 coincides with the
central galaxy (Owen & Rudnick 1976; Sakelliou & Merrifield 1999); it
exhibits a powerful jet that interacts the X-ray-emitting gas as far
out as 100 kpc from the cluster center. For this reason, our entropy
and pressure profiles miss the central section of the cluster
entirely.

2. 2002ApJ...567..202E
Re:ABELL 2634
2.2. Abell 2634
Abell 2634 is a richness class 1, Rood-Sastry cD cluster. It has a mean
z = 0.0313 (Pinkney et al. 1993), which corresponds to 35.2 kpc arcmin^-1^.
Its dynamics and structure have been studied by Pinkney et al. and by
Scodeggio et al. (1995). While the dynamical situation is not totally clear,
both papers agree on the most likely picture. The cluster itself does not
show any evidence of substructure, either in velocity or physical space.
The cluster sits in a complex area of the sky that also contains the lower
redshift Pisces-Perseus supercluster. Two groups of galaxies sit ~1deg to the
east, one high-velocity and low-velocity relative to A2634. When these
groups are excluded, the velocity and spatial structure of A2634 are
consistent with a relaxed cluster. Thus, based on the velocity field there
is no evidence that A2634 is currently undergoing a major merger.
The X-ray image of this cluster is more complex than the optical data
would suggest. On large scales the isophotes are more or less regular, but
on small scales a striking central elongation appears. Figure 2 shows the
image from the ROSAT PSPC, together with the central radio galaxy (Eilek
et al. 1984; see also Schindler & Prieto 1996, who present inner X-ray
isophotes). The distorted central X-ray distribution has no counterpart in
the optical image. Although Schindler & Prieto (1996) argue against this
distortion being caused by a merger, Roettiger, Loken, & Burns (1997) find
that such structures can indeed occur in the later stages of a merger. They
find density elongations and bulk flows along the merger axis. As with
Abell 400, there is no significant evidence of a cooling core in A2634
(White et al. 1997, who agree with earlier work).
The central galaxy also has a double nucleus (Lauer 1988). One of the
nuclei gives rise to a large, tailed radio galaxy, 3C 465 (Eilek et al. 1984).
The radio tails can be detected to ~7' ~250 kpc at 327 MHz. They bend to the
southwest, toward (and around) the X-ray elongation. Our RM map, again based
on high frequencies, covers only the inner region, extending to ~230" ~135 kpc.

3. 2002ApJ...567..202E
Re:ABELL 2634
Abell 2634 contains 3C 465, a wide-angle tail radio source. The spectrum can
be described by a single power law, {alpha} ~ 0.8 (KPTW). Eilek et al. (1984)
present radio images and the Einstein data; the Faraday data and ROSAT data
are discussed in the present paper. In section 4 we take the typical
T~1.5 keV. This cluster has a broad gas core, making it a noncooling cluster,
but also has a weak central X-ray excess, which may be a small cooling core.

4. 2002AJ....123.2159B
Re:ABELL 2634
A2634.This is one of the most distant clusters in the ENEARc
sample (cz ~ 9000 km s^-1^) and has a large peculiar velocity
(it is more than 2{sigma} from the mean defined by our full
sample). We have no measurements of our own for this cluster.
Lucey et al. (1997) reobserved some of its galaxies and
concluded that the original values of the central velocity
dispersion were underestimated. This partially accounts for
its large infall velocity. Here the peculiar velocity was
determined using the Lucey et al. (1997) estimates, converted
to our system. Although our value (approximately -1787 km s^-1^)
is smaller than the number reported in Faber et al. (1989) and
Lucey et al. (1991) (-3400 +/- 600 km s^-1^), it also disagrees
with the more recent estimate from Lucey et al. (1997) and the
estimate from the SCI sample of cluster spirals (G97). The
Lucey et al. (1997) value is significantly smaller
(<~-700 km s^-1^) than ours, with the actual value depending on
the distance relation used (FP or D_n-{sigma}_ ). In the SCI
sample this cluster is nearly at rest relative to the Hubble
flow. Hudson et al. (1997), using a subsample of the
Lucey et al. (1997) data set and the FP relation in their
paper, also find a small infall. However, using the slope of
their D_n-{sigma}_ relation and a zero point derived from the
peculiar velocities of the other two clusters we have in common
with them, A347 and 7S 21 (because the zero point of the D_n-{sigma}_
relation is not reported in that paper), yields a peculiar
velocity of -1582 +/- 635 km s^-1^ for A2634, comparable to our
value. We also note that A2634 has a nearby companion (A2166)
at approximately the same redshift, which may affect membership
assignment and may explain the large variations in its measured
peculiar velocity.

5. 1999MNRAS.306..857C
Re:ABELL 2634
The observed galaxy (NGC 7720) is associated with 3C 465.

6. 1997ApJ...482...41G
Re:ABELL 2634
A2634-2666.-The MS sample includes both A2634 and the tiny cluster A2666
(S1) and a further substructure (S2). We identify A2634 with the MS - S1
- S2 sample, i.e., the MS sample after the rejection of A2666 and S2,
which are both unbound to the remaining galaxies. The "identified
cluster" main properties are: center 1950 ({alpha}, {delta}) =
23^h^36^m^06.9^s^, +26^deg^45'41"; N= 216, R_max_ = 5.64; v^bar^ = 9136
km s^-1^; P_w_ < 0.1%; {sigma} = 886. Scodeggio et al. (1995) did not
find any evidence of substructures in the central cluster region. The
{sigma} of the MS - S1 - S2 sample is in good agreement with the T at
about 1 h^-1^ Mpc, and an increase in the outer region is likely because
of the presence of some remaining interlopers. The T of A2666 is much
higher than our value of {sigma}, but we note that this T is estimated
from X-ray luminosity.


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