Questions via youtube chat
Prospects for Dark Matter Detection in Dwarf Irregular Galaxies with Gamma Rays
INFN, Trieste & SISSA
Alejandro de la Puente
We investigate rotationally supported dwarf irregular (dIrr) galaxies as new targets for dark matter indirect search with gamma-ray telescopes. Differently from pressure supported objects, their dynamic provides to well constrain the DM distribution in the halo. We present the astrophysical factor for a sample of 36 dIrr galaxies. The range of values spreads out over 10¹⁴ – 10¹⁸ GeV²cm⁻⁵ turning out to be comparable with the astrophysical factor of well known dwarf spheroidal galaxies, that is 10¹² – 10²⁰ GeV²cm⁻⁵. The existence of the star forming region in dIrrs constitutes an extra background, that is instead negligible in dwarf spheroidal galaxies. On the one hand, such unresolved gamma-ray emission may represent a component of the diffuse isotropic gamma-ray background. On the other, we show that it may be masked or neglected with the intent of DM search in the extended halo. The detection of an extended DM component would constitute a smoking gun for DM particle annihilation. We individuate IC10 and WLM as the best candidates in our sample of galaxies. We get the first constraints for the DM annihilation cross-section with the current and next generation of gamma-ray telescopes.