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Session 37 - Clusters of Galaxies - X-Rays.
Display session, Tuesday, January 14
Metropolitan Ballroom,

[37.08] Abell 754: The Evolution of an Off-axis Merger.

K. Roettiger (GSFC/UMd), J. M. Stone (U. Maryland), R. F. Mushotzky (GSFC)

A754 is a well-observed cluster of galaxies which exhibits a variety of morphological peculiarities including a bar of X-ray emission that is offset significantly from the galaxy distribution, an elongated X-ray surface brightness distribution extending between two distinct peaks in the galaxy distribution, and an extremely non-isothermal and asymmetric ICM temperature morphology. Using these observational constraints, we present a high resolution numerical Hydro/N-body model of A754 in which two clusters (2.5:1 mass ratio) have merged nearly in the plane of the sky less than 0.5 Gyrs ago with an impact parameter of \sim150 kpc. This model allows us to study the current dynamical state of the X-ray emitting gas in this system making possible detailed predictions for future high resolution X-ray spectroscopic observations (e.g. ASTRO-E). In this analysis, we discuss the origin of A754's peculiar X-ray and temperature morphologies, the underlying hydrodynamical processes that shape them, and their future evolution. We also address the role of mergers in the mixing of gas components within the ICM.


Program listing for Tuesday