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arXiv · 1705.00426

Constraints on dark matter models from the observation of Triangulum-II with the Fermi Large Area Telescope

Sayan Biswas·Pooja Bhattacharjee·Pratik Majumdar·Subinoy Das·Mousumi Das·Parthasarathi Joarder
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Abstract

Triangulum-II, a newly discovered dwarf spheroidal galaxy, is a strong candidate for the indirect search of dark matter through the detection of $\gamma$-ray emission that could originate from the pair- annihilation of weakly interacting massive particles (WIMPs). We here report on the analysis of almost seven years Fermi Gamma-Ray Space Telescope data of Triangulum-II which was taken during its all sky survey operation mode. No excess $\gamma$-ray emission has been detected above 100 MeV from Triangulum-II. We derive the upper limits on $\gamma$-ray flux assuming both the power-law spectra and the spectra related to WIMP annihilation. In this work, we have considered several theoretical WIMP (neutralinos here) models envisioning both thermal and non-thermal production of WIMPs, and put limits on pair-annihilation cross-section of WIMPs to constrain the parameter space related to those theoretical models.

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Sayan Biswas, Pooja Bhattacharjee, Pratik Majumdar, Subinoy Das, Mousumi Das, Parthasarathi Joarder. 2017-05-01. Constraints on dark matter models from the observation of Triangulum-II with the Fermi Large Area Telescope. https://doi.org/10.1088/1475-7516%2F2017%2F11%2F003

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