Suzaku Observations of the X-ray Brightest Fossil Group ESO 3060170
  "Fossil" galaxy groups, each dominated by a relatively isolated giant
elliptical galaxy, have many properties intermediate between groups and
clusters of galaxies. We used the {\sl Suzaku} X-ray observatory to observe the
X-ray brightest fossil group, ESO 3060170, out to $R_{200}$, in order to better
elucidate the relation between fossil groups, normal groups, and clusters. We
determined the intragroup gas temperature, density, and metal abundance
distributions and derived the entropy, pressure and mass profiles for this
group. The entropy and pressure profiles in the outer regions are flatter than
in simulated clusters, similar to what is seen in observations of massive
clusters. This may indicate that the gas is clumpy and/or the gas has been
redistributed. Assuming hydrostatic equilibrium, the total mass is estimated to
be $\sim1.7\times10^{14}$ $M_{\odot}$ within a radius $R_{200}$ of $\sim1.15$
Mpc, with an enclosed baryon mass fraction of 0.14. The integrated iron
mass-to-light ratio of this fossil group is larger than in most groups and
comparable to those of clusters, indicating that this fossil group has retained
the bulk of its metals. A galaxy luminosity density map on a scale of 25 Mpc
shows that this fossil group resides in a relatively isolated environment,
unlike the filamentary structures in which typical groups and clusters are
embedded.
