Deep, multi-epoch Chandra observations of the nearby, gas poor ellipticals NGC 3379 and NGC 4278 have revealed non-uniform spatial distributions of low mass X-ray binaries (LMXB). Comparisons of these populations to their optical morphology indicates that the LMXB distributions are inconsistent with that of their old stellar population. In NGC 3379 the distribution of the LMXB population appears as a prolate disk, whilst in NGC 4278 a loop of LMXBs has been identified on one side of this galaxy. In addition to these X-ray data, both systems have been observed with WFPC2 on-board HST, providing information about the globular cluster (GC) population within each galaxy.
Here I will discuss the correlations identified between the LMXBs and GCs within the context of their spatial distribution, focusing particularly on the loop feature within NGC 4278. In this region ~70% of the LMXBs are coincident with a GC, with color information indicating that these LMXBs predominately reside within red (metal-rich) systems. Such a correlation could suggest that the non-uniform X-ray source distribution arises from the GC system and I will present N-body simulations to explore such a scenario and suggest evolutionary paths that could lead to these observed anisotropies.
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