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arXiv · 2402.07976

First Result for Dark Matter Search by WINERED

Abstract

The identity of dark matter has been a mystery in astronomy, cosmology, and particle theory for about a century. Bessho, Ikeda, and Yin (2022), three of the current authors, proposed using the state-of-the-art infrared spectrographs, including WINERED at $6.5$m Magellan Clay telescope and NIRSpec at James Webb Space Telescope, as efficient detectors for the indirect detection of dark matter with the mass around eV by measuring the line photons from the dark matter two body decays. Applying this concept, we have performed spectrographic observations of dwarf spheroidal galaxies (dSphs) Leo V and Tucana II using WINERED by utilizing an object-sky-object nodding observation technique for background subtraction. We present the first result from this dark matter search. Employing zero consistent flux data after the sky subtraction, we have established one of the most stringent limits to date on dark matter decaying into line photons in the mass range of $1.8-2.7\,$eV. Our data can also be applied to constrain other spectra of photons from the dSphs.

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Wen Yin, Taiki Bessho, Yuji Ikeda, Hitomi Kobayashi, Daisuke Taniguchi, Hiroaki Sameshima, Noriyuki Matsunaga, Shogo Otsubo, Yuki Sarugaku, Tomomi Takeuchi, Haruki Kato, Satoshi Hamano, Hideyo Kawakita. 2024-02-12. First Result for Dark Matter Search by WINERED. https://arxiv.org/abs/2402.07976

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