Jared Diks | Searcharxiv

arXiv2024

Constraining Asymmetric DM Properties by Black Hole Formation in Neutron Stars and Population III Stars

In this work we explore the potential for Neutron Stars (NSs) at the Galactic center and Population~III stars to constrain bosonic Asymmetric Dark Matter (ADM). We demonstrate that for NSs in an environment of sufficiently high DM density ($\rho_\chi\gtrsim10^{9}\text{GeV/cm}^3$), the effects of both multiscatter capture and DM evaporation cannot be neglected. Conversely, for Pop~III stars, we find they are excellent at probing low-mass ADM. For instance, the most easily observable Population III stars could be highly effective at constraining high-$\sigma$ low-$m_\chi$ DM, maintaining efficacy below $m_\chi=10^{-15}\text{GeV}$ (assuming a Bose Einstein Condensate(BEC) forms) thanks to their far lower value of $m_\chi$ at which capture saturates to the geometric limit. Finally, we derive closed-form approximations for the evaporation rate of DM from arbitrary polytropic objects and from DM particles in a BEC state.

astro-ph.CO↗

arXiv2023

The effectiveness of exoplanets and Brown Dwarfs as sub-GeV Dark Matter detectors

In this work we demonstrate that Dark Matter (DM) evaporation severely hinders the effectiveness of exoplanets and Brown Dwarfs as sub-GeV DM probes. Moreover, we find useful analytic closed form approximations for DM capture rates for arbitrary astrophysical objects, valid in four disticnt regions in the $\sigma-m_X$ parameter space. As expected, in one of those regions the Dark Matter capture saturates to its geometric limit, i.e. the entire flux crossing an object. As a consequence of this region, which for many objects falls within the parameter space not excluded by direct detection experiments, we point out the existence of a DM parameter dependent critical temperature ($T_{crit}$), above which astrophysical objects lose any sensitivity as Dark Matter probes. For instance, Jupiters at the Galactic Center have a $T_{crit}$ ranging from $700$ K (for a $3 M_J$ Jupiter) to $950$ K (for $14 M_J$). This limitation is rarely (if ever) considered in the previous literature of indirect Dark Matter detection based on observable signatures of captured Dark Matter inside celestial bodies.

astro-ph.CO↗