Limits from the grave: resurrecting Hitomi for decaying dark matter and forecasting leading sensitivity for XRISM
Abstract
The Hitomi X-ray satellite mission carried unique high-resolution spectrometers that were set to revolutionize the search for sterile neutrino dark matter (DM) by looking for narrow X-ray lines arising from DM decays. Unfortunately, the satellite was lost shortly after launch, and to-date the only analysis using Hitomi for DM decay used data taken towards the Perseus cluster. In this work we present a significantly more sensitive search from an analysis of archival Hitomi data towards blank sky locations, searching for DM decaying in our own Milky Way. The soon-to-be-launched XRISM satellite will have nearly identical soft-X-ray spectral capabilities to Hitomi; we project the full-mission sensitivity of XRISM for analyses of their future blank-sky data, and we find that XRISM will have the leading sensitivity to decaying DM for masses between roughly 1 to 20 keV, with important implications for sterile neutrino and heavy axion-like particle DM scenarios.
- Publication:
-
arXiv e-prints
- Pub Date:
- May 2023
- DOI:
- 10.48550/arXiv.2305.17160
- arXiv:
- arXiv:2305.17160
- Bibcode:
- 2023arXiv230517160D
- Keywords:
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- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - High Energy Astrophysical Phenomena;
- High Energy Physics - Phenomenology
- E-Print:
- 7+6 pages, 3+8 figures, supplementary data at https://github.com/bsafdi/Hitomi_BSO_for_DM, video abstract at https://youtu.be/EXBo-WHwwMw