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I'm looking for something to cite about galaxy mergers in clusters of galaxies.

I need numbers on the frequency of mergers in the outer parts of galaxy clusters vs. the cluster center. In the center number densities are higher but so is the velocity dispersion.

Are mergers of galaxies more likely to occur in the outskirts or the central region of galaxy cluster?

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Do you have a preference on simulation vs. observational based evidence of galaxy merger rates? –  Aaron Aug 27 at 15:45
+1 good question. I cannot provide an answer, but in general merging in clusters is rather rare (because the galaxies' mutual velocity is $\sim1000$km/s, much higher than their own velocity dispersion), in contrast to galaxy groups. On the other hand, the central cluster galaxy is almost certainly a merger remnant, but may have merged before the cluster was established. Minor merging activity onto the central cluster galaxy is presumably common. –  Walter Aug 27 at 15:48
Well clusters form hierarchical, and galaxy do fall in in pairs and small groups so the velocity dispersion is not really an argument. Mergers are more frequent than one might think (Mihos 03, Gnedin 03, McGee 09, Berrier 09, DeLucia 12), but still by no means a common event. All the papers mentioned have touched on the subject one way or another but not quiet what I was looking for. –  con-f-use Aug 28 at 12:03
@Aaron: Both are interesting. –  con-f-use Aug 28 at 12:31

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