Back and forth from cool core to non-cool core: clues from radio-halos

Details Back and forth from cool core to non-cool core: clues from radio-halos Back and forth from cool core to non-cool core: clues from radio-halos

2011-06-22

arxiv.org/abs/1106.4563v1

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

Accepted for publication in A&A

Scientific paper

X-ray astronomers often divide galaxy clusters into two classes: "cool core" (CC) and "non-cool core" (NCC) objects. The origin of this dichotomy has been the subject of debate in recent years, between "evolutionary" models (where clusters can evolve from CC to NCC, mainly through mergers) and "primordial" models (where the state of the cluster is fixed "ab initio" by early mergers or pre-heating). We found that in a well-defined sample (clusters in the GMRT Radio halo survey with available Chandra or XMM-Newton data), none of the objects hosting a giant radio halo can be classified as a cool core. This result suggests that the main mechanisms which can start a large scale synchrotron emission (most likely mergers) are the same that can destroy CC and therefore strongly supports "evolutionary" models of the CC-NCC dichotomy. Moreover combining the number of objects in the CC and NCC state with the number of objects with and without a radio-halo, we estimated that the time scale over which a NCC cluster relaxes to the CC state, should be larger than the typical life-time of radio-halos and likely shorter than about 3 Gyr. This suggests that NCC transform into CC more rapidly than predicted from the cooling time, which is about 10 Gyr in NCC systems, allowing the possibility of a cyclical evolution between the CC and NCC states.

Affiliated with

Also associated with

No associations

Rating

Back and forth from cool core to non-cool core: clues from radio-halos does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Back and forth from cool core to non-cool core: clues from radio-halos, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Back and forth from cool core to non-cool core: clues from radio-halos will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-468865