IC 1262 has rich substructure within its core. However, beyond the central 60
kpc radius, it appears symmetrical and relaxed. Its surface brightness profile
shows a sharp break at ~ 200 kpc. Unlike 3C 442A and A2462, its radio source is
faint. However, this may be caused by past AGN activity, which was also
suggested to explain the rich structures in the group core by Trinchieri et al.
(2007). The sharp temperature decline beyond 200 kpc also supports this
scenario, as the regions between 80 and 200 kpc radius may have been recently
heated (Figure 4). The adiabatic sound speed in ~ 1.9 keV gas is ~ 700 km s^-1^.
Thus, a Mach 1.5 shock will travel to the current position in ~ 200 Myr, which
is consistent with the typical duty cycle of radio AGN.
A large number of galaxies near