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arXiv · 1507.04744

Dark Matter Velocity Spectroscopy

Eric G. Speckhard·Kenny C. Y. Ng·John F. Beacom·Ranjan Laha
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Abstract

Dark matter decays or annihilations that produce line-like spectra may be smoking-gun signals. However, even such distinctive signatures can be mimicked by astrophysical or instrumental causes. We show that velocity spectroscopy-the measurement of energy shifts induced by relative motion of source and observer-can separate these three causes with minimal theoretical uncertainties. The principal obstacle has been energy resolution, but upcoming experiments will reach the required 0.1% level. As an example, we show that the imminent Astro-H mission can use Milky Way observations to separate possible causes of the 3.5-keV line. We discuss other applications.

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Eric G. Speckhard, Kenny C. Y. Ng, John F. Beacom, Ranjan Laha. 2015-07-31. Dark Matter Velocity Spectroscopy. https://doi.org/10.1103/physrevlett.116.031301

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