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Date and Time of the Query: 2019-06-15 T16:24:42 PDT
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Notes for object ABELL 0697

3 note(s) found in NED.


1. 2005MNRAS.357..518J
Re:ABELL 0697
3.4 A697 - A697 was observed with the ROSAT HRI on 1995 November 6 with a live
time of 28.1 ks. We also observed it using ASCA during 1996 April to determine
its temperature. Analysing both the Gas Imaging Spectrometer (GIS) and the
Solid-State Imaging Spectrometer (SIS) data using standard xspec tools, we find
a temperature of 8.0^+0.6^_-0.4_ keV (68 per cent confidence), with a
metallicity of 0.24 +/- 0.07 solar. By fitting to the ROSAT HRI data, we find
the parameters given in Table 2. The HRI image, model and residuals are shown in
Fig. 2.
We observed A697 with the RT on 42 occasions between 1994 August 6 and 1996
April 27. The map of all the data is shown in Fig. 3. The bright source to the
northwest is extended, but can be successfully modelled as three point sources.
Fitting simultaneously to the sources and SZ decrement gives a good fit with the
source parameters listed in Table 3. Fitting the source-subtracted data to the
model derived from the X-ray data (Fig. 4), and applying the relativistic and
flux-scale corrections, we find H_0_= 52^+8^_-6_ km s^-1^ Mpc^-1^ (errors from
SZ fitting only). Including the other random errors, dominated by the X-ray
temperature (^+14^_-10_ per cent) and ellipticity (+/-30 per cent), we find
H_0_= 52^+18^_-14_ km s^-1^ Mpc^-1^. For a {LAMBDA}CDM cosmology with
{OMEGA}_M_= 0.3 and {OMEGA}_{LAMBDA}_= 0.7, this becomes H_0_= 59^+21^_-16_ km
s^-1^ Mpc^-1^.

2. 2002ApJS..139..313D
Re:ABELL 0697
5.9. A697 This is one of the most massive clusters in our sample.
The halo of the central cD galaxy in this cluster has a peculiar
disturbed morphology, indicative of a recent merger. There are
two arc candidates in this cluster, discovered by Metzger & Ma
(2000). The positions of the peaks in the mass, light, and
number density distributions coincide very well, although the
mass distribution is more elongated than the latter two. The
mass distribution is elongated along the major axis of the
faint, outer parts of the cD halo (which shows strongly twisting
isophotes), and this may indicate a recent head-on collision of
two mass clumps along this axis. The central cD galaxy has a
double nucleus, which also supports the merger hypothesis. An
X-ray image from a 28 ks ROSAT HRI exposure shows an elliptical
X-ray luminosity distribution with a position angle similar to
that of the dark matter. A comparison of the mass and light maps
in Figure 24 clearly shows that A697 has an unusually high
mass-to-light ratio (see also H. Dahle et al. 2002c, in
preparation). A697 also has the lowest SZ-derived gas mass
fraction of the 18 clusters measured by Grego et al. (2001),
raising the interesting possibility that this is an unusually
"baryon-poor" cluster.

3. 2001ApJ...548..639K
Re:ABELL 0697
A697. - The diffuse emission is located in the cluster center and
extends to the northwest. The peak of the emission is roughly coincident
with the X-ray centroid of the cluster. The absence of point sources in
this region in the FIRST survey and the lack of bright ellipticals in the
DSS suggest that the diffuse emission is in fact real, despite its low
flux. Because of the large uncertainties in its flux, however, we will
consider it to be uncertain until deeper, more detailed observations can
be made.


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