Multicomponent multiscatter capture of Dark Matter

Abstract

In recent years, the usefulness of astrophysical objects as Dark Matter (DM) probes has become more and more evident, especially in view of null results from direct detection and particle production experiments. The potentially observable signatures of DM gravitationally trapped inside a star, or another compact astrophysical object, have been used to forecast stringent constraints on the nucleon-Dark Matter interaction cross section. Currently, the probes of interest are: at high redshifts, Population III stars that form in isolation, or in small numbers, in very dense DM minihalos at z ∼ 15 − 40, and, in our own Milky Way, neutron stars, white dwarfs, brown dwarfs, exoplanets, etc. Of those, only neutron stars are single-component objects, and, as such, they are the only objects for which the common assumption made in the literature of single-component capture, i.e. capture of DM by multiple scatterings with one single type of nucleus inside the object, is valid. In this paper, we present an extension of this formalism to multi-component objects and apply it to Pop III stars, thereby investigating the role of He on the capture rates of Pop III stars. As expected, we find that the inclusion of the heavier He nuclei leads to an enhancement of the overall capture rates, further improving the potential of Pop III stars as Dark Matter probes.

Heavy dark matter in white dwarfs: multiple-scattering capture and thermalization

“…In figure 3, we compare our approach with that of ref. [17] which addresses multi-target multiple-scattering capture in stars, neglecting the stellar structure. We consider a 0.94M ⊙ WD, which is composed mainly of carbon and oxygen.…”

“…As in the previous section, we assume the D1 EFT operator, since ref. [17] only deals with the case of constant DM-nucleon cross section. As we can see, the difference between the two approaches is not as striking as that observed in figure 2, with capture rates from ref.…”

“…Analytical approaches in the literature that deal with capture of heavy DM via multiple scattering in stars [5,[15][16][17] are based on Gould's seminal work for capture in the Earth [18]. It is worth noting that in the case of the Earth, the main contribution comes from the scattering of DM with iron nuclei.…”

Improved Treatment of Dark Matter Capture in Neutron Stars III: Nucleon and Exotic Targets

“…In Figs. 13 and 14, we compare our results for the QMC EoS with those for the BSk24 functional for NSs of the same mass, namely M = 1M and M = 1.5M 4 , assuming neutron targets. Note that we do not compare heavier NS configurations, since BSk24 is a minimal EoS that does not consider the presence of exotic matter in the inner core.…”

“…The basic framework for the capture of DM in stars is well established, built on the original formalism of Gould [1,2] and others [3][4][5][6]. It has primarily been applied in the context of the Sun [7][8][9][10] and stars [11][12][13]. Observable consequences of DM accumulation in the Sun include modifications to thermal transport in the solar interior [14][15][16][17], or signals arising from the annihilation of the accumulated DM, in the form of high energy neutrinos [18][19][20][21][22][23] or cosmic and gamma ray fluxes [24][25][26][27][28][29][30].…”