Abstract Details
| Name: Siddhant Manna Affiliation: IIT Hyderabad Conference ID: ASI2025_344 Title : Search for Dark Matter Annihilation to gamma-rays from SPT-SZ selected Galaxy Clusters Authors and Co-Authors : Siddhant Manna , Shantanu Desai Abstract Type : Poster Abstract Category : High Energy Phenomena, Fundamental Physics and Astronomy Abstract : We search for dark matter annihilation from galaxy clusters in the energy range from 1-300 GeV using nearly 16 years of Fermi-LAT data. For this purpose, we use 350 galaxy clusters selected from the 2500 deg2 SPT-SZ survey. We model the dark matter distribution using the NFW profile for the main halo along with the Einasto profile for the substructure. The largest signal is seen for the cluster SPT-CL J2021-5257 with a significance of around 3σ. The best-fit dark matter mass and annihilation cross-section for this cluster are equal to (60.0±11.8) GeV and ⟨σv⟩=(6.0±0.6)×10^−25 cm^3 s^−1 for the b¯b annihilation channel. However, this central estimate is in conflict with the limits on annihilation cross-section from dwarf spheroidal galaxies, and hence cannot be attributed to dark matter annihilation. Three other clusters show significance between 2−2.5σ, whereas all the remaining clusters show null results. The most stringent 95\% c.l. upper limit for the WIMP annihilation cross-section among all the clusters is from SPT-CL J0455-4159, viz. ⟨σv⟩=6.44×10^−26 cm^3 s^−1 for m_χ=10 GeV and bb¯ annihilation channel. |