http://arxiv.org/abs/1711.02556
The absence of any confirmative signals from extensive DM searching motivates us to go beyond the conventional WIMPs scenario. The feebly interacting massive particles (FIMPs) paradigm provides a good alternative which, despite of its feebly interaction with the thermal particles, still could correctly produce relic abundance without conventional DM signals. The Infrared-FIMP based on the renormalizable operators is usually suffering the very tiny coupling drawback, which can be overcome in the UltraViolet-FIMP scenario based on high dimensional effective operators. However, it is sensitive to the history of the very early Universe. The previous works terminates this sensitivity at the reheating temperature $T_{RH}$. We, motivated by its UV-sensitivity, investigate the effects from the even earlier Universe, reheating era. We find that in the usual case with $T_{RH}\gg m_{\rm DM}$, the production rate during reheating is very small as long as the effective operators dimension $d \leq 8$. Besides, we consider the contribution from the mediator, which may be produced during reheating. Moreover, we study the situation when $T_{RH}$ is even lower than $m_{\rm DM}$ and DM can be directly produced during reheating if its mass does not exceed $T_{MAX}$.
S. Chen and Z. Kang
Wed, 8 Nov 17
14/84
Comments: 17 pages, no figures
You must be logged in to post a comment.