Abstract
A new Chandra observation of the northwest region of the galaxy cluster A1367 reveals four cool galaxy coronae (0.4-1.0 keV) embedded in the hot (5-6 keV) intracluster medium (ICM). While the large coronae of NGC 3842 and NGC 3837 appear symmetric and relaxed, the galaxy coronae of the ≲L* galaxies (NGC 3841 and CGCG 97090) are disturbed and being stripped. Massive galaxies, generally with dense cooling cores, are better able to resist ram pressure stripping and survive in rich environments than ≲L* galaxies, whose galactic coronae are generally much less dense. The survival of these cool coronae implies that thermal conduction from the hot surrounding ICM has to be suppressed by a factor of at least 60 at the corona boundary. Within the galaxy coronae of NGC 3842 and NGC 3837, stellar mass loss or heat conduction with the Spitzer value may be sufficient to balance radiative cooling. Energy deposition at the ends of collimated jets may heat the outer coronae but allow the survival of a small, dense gas core (e.g., NGC 3842 in A1367 and NGC 4874 in the Coma Cluster). The surviving X-ray coronae become significantly smaller and fainter with the increasing ambient pressure.
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