2 research outputs found
A note on the primordial abundance of stau NLSPs
In scenarios with a gravitino LSP, there exist strong BBN constraints on the
abundance of a possible stau NLSP. We find that in settings with substantial
left-right mixing of the stau mass eigenstates these constraints can be evaded
even for very long-lived staus.Comment: 17 pages, 5 figures, discussion on vacuum stability adde
The Number Density of a Charged Relic.
We investigate scenarios in which a charged, long-lived scalar particle
decouples from the primordial plasma in the Early Universe. We compute the
number density at time of freeze-out considering both the cases of abelian and
non-abelian interactions and including the effect of Sommerfeld enhancement at
low initial velocity. We also discuss as extreme case the maximal cross section
that fulfils the unitarity bound. We then compare these number densities to the
exotic nuclei searches for stable relics and to the BBN bounds on unstable
relics and draw conclusions for the cases of a stau or stop NLSP in
supersymmetric models with a gravitino or axino LSP.Comment: 45 page