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arXiv · 1604.01494

Sommerfeld enhancement of invisible dark matter annihilation in galaxies and galaxy clusters

Man Ho Chan
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Abstract

Recent observations indicate that core-like dark matter structures exist in many galaxies, while numerical simulations reveal a singular dark matter density profile at the center. In this article, I show that if the annihilation of dark matter particles gives invisible sterile neutrinos, the Sommerfeld enhancement of the annihilation cross-section can give a sufficiently large annihilation rate to solve the core-cusp problem. The resultant core density, core radius, and their scaling relation generally agree with recent empirical fits from observations. Also, this model predicts that the resultant core-like structures in dwarf galaxies can be easily observed, but not for large normal galaxies and galaxy clusters.

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Man Ho Chan. 2016-04-06. Sommerfeld enhancement of invisible dark matter annihilation in galaxies and galaxy clusters. https://doi.org/10.1016/j.astropartphys.2016.03.005

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