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arXiv · 0704.0381

The collision velocity of the bullet cluster in conventional and modified dynamics

Garry W. Angus·Stacy S. McGaugh
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Abstract

We consider the orbit of the bullet cluster 1E 0657-56 in both CDM and MOND using accurate mass models appropriate to each case in order to ascertain the maximum plausible collision velocity. Impact velocities consistent with the shock velocity (~ 4700km/s) occur naturally in MOND. CDM can generate collision velocities of at most ~ 3800km/s, and is only consistent with the data provided that the shock velocity has been substantially enhanced by hydrodynamical effects.

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Garry W. Angus, Stacy S. McGaugh. 2007-09-02. The collision velocity of the bullet cluster in conventional and modified dynamics. https://doi.org/10.1111/j.1365-2966.2007.12403.x

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