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arXiv · astro-ph/0507222

Galaxy Cluster Masses Without Non-Baryonic Dark Matter

Abstract

We apply the modified acceleration law obtained from Einstein gravity coupled to a massive skew symmetric field, F_{μνλ}, to the problem of explaining X-ray galaxy cluster masses without exotic dark matter. Utilizing X-ray observations to fit the gas mass profile and temperature profile of the hot intracluster medium (ICM) with King beta-models, we show that the dynamical masses of the galaxy clusters resulting from our modified acceleration law fit the cluster gas masses for our sample of 106 clusters without the need of introducing a non-baryonic dark matter component. We are further able to show for our sample of 106 clusters that the distribution of gas in the ICM as a function of radial distance is well fit by the dynamical mass distribution arising from our modified acceleration law without any additional dark matter component. In previous work, we applied this theory to galaxy rotation curves and demonstrated good fits to our sample of 101 LSB, HSB and dwarf galaxies including 58 galaxies that were fit photometrically with the single parameter (M/L)_{stars}. The results there were qualitatively similar to those obtained using Milgrom's phenomenological MOND model, although the determined galaxy masses were quantitatively different and MOND does not show a return to Keplerian behavior at extragalactic distances. The results here are compared to those obtained using Milgrom's phenomenological MOND model which does not fit the X-ray galaxy cluster masses unless an auxiliary dark matter component is included.

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BibTeXRIS

J. R. Brownstein, J. W. Moffat. 2005-07-08. Galaxy Cluster Masses Without Non-Baryonic Dark Matter. https://doi.org/10.1111/j.1365-2966.2006.09996.x

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