Dark Matter Annihilation in 21cm Signal at Cosmic Dawn

          @misc{ scivideos_PIRSA:24020042,
            doi = {10.48660/24020042},
            url = {https://pirsa.org/24020042},
            author = {Hou, Liqiang},
            keywords = {Cosmology},
            language = {en},
            title = {Dark Matter Annihilation in 21cm Signal at Cosmic Dawn},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2024},
            month = {feb},
            note = {PIRSA:24020042 see, \url{https://scivideos.org/index.php/pirsa/24020042}}
          }
          

Abstract

We will present our study of the interaction of dark matter (DM) annihilation with primordial gas during cosmic dawn, emphasizing its impact on the thermal environment of nearby dark matter halos. Utilizing a semi-analytic model, we analyze DM annihilation across redshifts $z=20 to 40$, uncovering its role in altering baryon history and impeding gas collapse and cooling in mini-halos, which affects PopIII star formation. Our study also integrates streaming velocity effects to simulate the 21-cm hydrogen line signal using the 21cmvFAST code. This approach offers a detailed view of astrophysical processes in the early universe. We will present findings demonstrating DM annihilation's significant influence on early star formation and the observable characteristics of the neutral hydrogen line. Our presentation aims to enhance our understanding of baryon physics in the cosmic dawn and provide insights into dark matter models and early galactic and stellar formation.