Constraining Dark Matter Self-interactions: Hints of the Dark Force and Beyond
by
Oindrila Ghosh(Institute of Mathematical Sciences Chennai)
→
Europe/Berlin
67/10 (DESY Hamburg)
67/10
DESY Hamburg
Description
Abstract:
Velocity dependent self-interacting dark matter (vdSIDM) offers resolution to the
anomalies in the small-scale structure of the universe, the missing satellite problem,
the “too big to fail” problem and even the cusp vs. core problem. Although baryonic
feedbacks may account for some of these problems, in part or completely, the
self-interaction of dark matter preserves the success of the collisionless dark matter
in larger scales and is shown to be consistent with the halo shape observations and
Bullet cluster constraints. Motivated by the threefold advantages of vdSIDM, we
look beyond the standard cold collisionless regime. In this talk I will explore
non-relativistic self-interaction mediated by a dark photon like vector boson described
by a Yukawa potential and discuss the behavior of the momentum-transfer cross section
σ/m χ for self-scattering in different scales such as dwarfs, Milky Way and galactic clusters
for both symmetric and asymmetric dark matter. In the light of recent results from
Chandra and Hubble Space Telescopes, collisions between galactic clusters could confine
the parameter space for vdSIDM in a very stringent manner.
