Mar. 16/01/2018 14:00 Grande Ourse, Bâtiment 13, Etage 1
LOPEZ-HONOREZ Laura (Universite Libre de Bruxelles)
The 21cm window on particle dark matter
(LUPM/Interactions fondamentales, Astroparticules et Cosmologie)
Cosmology provide complementary probes of the nature of dark matter compared to particle physics experiments. This is for example the case with Planck constraints on the dark matter annihilation cross-section. Future dedicated radio interferometers, including HERA and SKA, are very promising tools that aim to study the epoch of reionization and beyond via measurements of the 21 cm signal from neutral hydrogen. In my talk, I will discuss how dark matter (DM) annihilations into SM particles can change the thermal history of the Universe and, as a consequence, affect the 21 cm signal. In addition, if time permits, I will also discuss the case of non cold dark matter scenarios, giving rise to suppressed structure formation on small scales with respect to the cold dark matter case, reduce the number of low-mass halos and the fraction of ionized gas at high redshifts and thus, delaying reionization. This has an impact on the ionization history of the Universe and measurements of the optical depth to reionization, of the evolution of the global fraction of ionized gas and of the thermal history of the intergalactic medium, can be used to set constraints on the mass of the dark matter particle.
Pour plus d'informations, merci de contacter Lavalle J.