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arXiv · 2208.12271

Constraining Sterile Neutrino Dark Matter in the Milky Way Halo with Swift-XRT

Dominic Sicilian·Dannell Lopez·Massimo Moscetti·Esra Bulbul·Nico Cappelluti
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Abstract

We present a search for sterile neutrino dark matter decay signals in the Milky Way's dark matter halo by considering the entirety of the Swift-XRT data archive. After filtering the raw archive, we analyze a $\sim$77 Ms data set containing the full field of view, as well as a $\sim$41 Ms data set with point-sources excised using the Swift-XRT Point Source catalog. We report non-detections of emission lines across the 3--6 keV continuum in both data sets, including at and around 3.5 keV. The point-sources excised data set is found to have higher sensitivity to faint dark matter decay signals due to its freedom from point-source contamination and is thus used to set constraints. Non-detections across the total data set's continuum are used to constrain the sterile neutrino dark matter parameter space, marginally strengthening existing X-ray constraints. Non-detections at $\sim$3.5 keV in data subsets grouped by angular distance from the galactic center are used to constrain the 3.5 keV line's galactic intensity profile, providing the strongest constraints to date across $\sim$1/4 of the galaxy.

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Dominic Sicilian, Dannell Lopez, Massimo Moscetti, Esra Bulbul, Nico Cappelluti. 2022-08-25. Constraining Sterile Neutrino Dark Matter in the Milky Way Halo with Swift-XRT. https://doi.org/10.3847/1538-4357/ac9fcf

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