Constraining strong baryon–dark-matter interactions with primordial nucleosynthesis and cosmic rays

Abstract

Self-interacting dark matter (SIDM) was introduced by Spergel & Steinhardt to address possible discrepancies between collisionless dark matter simulations and observations on scales of less than 1 Mpc. We examine the case in which dark matter particles not only have strong self-interactions but also have strong interactions with baryons. The presence of such interactions will have direct implications for nuclear and particle astrophysics. Among these are a change in the predicted abundances from big bang nucleosynthesis (BBN) and the flux of γ-rays produced by the decay of neutral pions which originate in collisions between dark matter and Galactic cosmic rays (CR).From these effects we constrain the strength of the baryon-dark matter interactions through the ratio of baryon -dark matter interaction cross section to dark matter mass, s. We find that BBN places a weak upper limit to this ratio < ∼ 10 8 cm 2 g −1 . CR-SIDM interactions, however, limit the possible DM-baryon cross section to < ∼ 5 × 10 −3 cm 2 g −1 ; this rules out an energy-independent interaction, but not one which falls with center-of-mass velocity as s ∝ 1/v or steeper.

Constraints on the interactions between dark matter and baryons from the x-ray quantum calorimetry experiment

“…9. Measurements of primordial element abundances give an upper limit of σ Dn /m dm ∼ < 4 × 10 −16 cm 2 GeV −1 [49]. Since this upper bound lies well beyond the upper bound from disk stability, we do not include it in Fig.…”

“…9. We also do not display the constraints from cosmic rays [49] because they are derived from inelastic interactions that are model-dependent.…”

Dark Matter 2017

“…Moreover the effect of stable heavy baryons with mass m B 10 GeV/c 2 on the BBN is determined essentially by the inelastic cross section of the heavy baryon with the deuterium nuclei for T B ≤ 2.2 MeV. The D/H abundance uncertainty sets a very weak limit to this cross section in the region of many barns [15,69].…”

Dark matter phenomenology of high-speed galaxy cluster collisions

“…Dark matter (DM) has been described conventionally using the Cold Dark Matter (CDM) model, where the primary candidate for DM is a e-mail: crji@ncsu.edu an extremely massive (m DM ≈ 10-1000 GeV) particle interacting exclusively via the weak interaction -the so-called weakly interacting massive particle (WIMP) [1,2]. In recent years, observations began to suggest that DM can be interacting with the cross sections large enough to influence the formation of small-scale cosmological structures, the so-called self-interacting dark matter (SIDM) [3][4][5][6][7][8][9][10][11][12]. Recent theoretical works put forth various models of such self-interacting DM including mirror DM [13], flavor-oscillating DM [14], SIDM [15][16][17][18], etc.…”

“…The summary and conclusions follow in Sect. 4. In Appendix A, we provide the summary of the algorithms used in this work.…”