CLUSTERS OF GALAXIES Cluster Mergers and Cold Fronts.

CLUSTERS OF GALAXIES

Cluster Mergers and Cold Fronts

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Structure Formation

Cluster Formation

GasDark Matter

X-rayTemp

We discuss some of the physical processes that occurs during cluster merger

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Cluster Mergers

Cluster MergerDensity Entropy

1E0657Markevitch et al 2001.

1E0657

Cold Fronts In Merger Clusters

CHANDRA OBSERVATION OF A2142

M. Markevitch et al. 2000, ApJ, 541, 542

CHANDRA OBSERVATION OF A3667

A. Vikhlinin, M. Markevitch, S. S. Murray 2000, ApJ, 551, 160

The most natural explanation is that A3667 hosts a moving dense, cold gas cloud

Interpretation for the Cold Front

The ratio between the pressure in region 0 and 1 gives the cloud speed

The cold front is the contact surface

The external gas slows down at leadingedge but reaccelerates as it is squeezed to the sides