Esra Bulbul, Randall Smith, Adam Foster, Jean Cottam, Michael Loewenstein, Richard Mushotzky, Richard Shafer
We examine high signal to noise XMM-Newton EPIC and RGS observations to
determine the physical characteristics of the gas in the cool core and
outskirts of the nearby rich cluster A3112. The XMM-ESAS data reduction and
background modeling methods were used to analyze the XMM- Newton EPIC data.
From the EPIC data we find that the iron and silicon abundance gradients show
significant increase towards the center of the cluster while the oxygen
abundance profile is centrally peaked but has a shallower distribution than
that of iron. The X-ray mass modeling is based on the temperature and
deprojected density distributions of the intra-cluster medium determined from
EPIC observations. The total mass of A3112 obeys the M-T scaling relations
found using XMM-Newton and Chandra observations of massive clusters at R500.
The gas mass fraction at R500, is also consistent with the 7-year WMAP results.
The comparisons of line fluxes and flux limits on the Fe XVII and Fe XVIII
lines obtained from high resolution RGS spectra indicate that there is no
spectral evidence for cooler gas with temperature below 1.0 keV in the central
< 38" (~52 kpc) region of A3112. High resolution RGS spectra also yields an
upper limit to the turbulent motions in compact core of A3112 (185 km/s). We
find that the energy contribution of turbulence to total energy is less than 5
per cent. This upper limit is consistent with the amount of energy contribution
measured in recent high resolution simulations of relaxed galaxy clusters.
View original:
http://arxiv.org/abs/1110.4422
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