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Probing the gravitational potential of a nearby lensing cluster Abell 2104

H. Liang·L. Lemonon·I. Valtchanov·M. Pierre·G. Soucail
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Abstract

The cluster Abell 2104 is one of the lowest redshift clusters (z=0.153) known to have a gravitational lensing arc. We present detailed analysis of the cluster properties such as the gravitational potential using the X-ray data from ROSAT (HRI) and ASCA, as well as optical imaging and spectroscopic data from the CFHT. The cluster is highly luminous in the X-ray with a bolometric luminosity of Lx ~3x10^{45} ergs/s and a high gas temperature of ~10.4 keV. The X-ray emission extending out to at least a radius of 1.46 Mpc, displays significant substructure. The total mass deduced from the X-ray data under the assumption of hydrostatic equilibrium and isothermal gas, is found to be M_tot(r<1.46Mpc) ~(8.0 +/- 0.8)x10^{14} solar mass. The gas fraction within a radius of 1.46 Mpc is ~5-10%. The cluster galaxy velocity distribution has a dispersion of 1200 +/- 200 km/s with no obvious evidence for substructure. The total mass within 1.46 Mpc, deduced from Jean's equation using the observed galaxy number density distribution and velocity dispersion, is found to be \~6.8x10^{14} solar mass to ~2.6x10^{15} solar mass marginally consistent with the X-ray deduced total mass.

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H. Liang, L. Lemonon, I. Valtchanov, M. Pierre, G. Soucail. 2000-10-16. Probing the gravitational potential of a nearby lensing cluster Abell 2104. https://arxiv.org/abs/astro-ph/0010297

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