Co-SIMP Miracle

Abstract

We present a new mechanism for thermally produced dark matter, based on a semi-annihilationlike process, χ + χ + SM → χ + SM, with intriguing consequences for the properties of dark matter. First, its mass is low, 1 GeV (but 5 keV to avoid structure-formation constraints). Second, it is strongly interacting, leading to kinetic equilibrium between the dark and visible sectors, avoiding the structure-formation problems of χ + χ + χ → χ + χ models. Third, in the 3 → 2 process, one dark matter particle is consumed, giving the standard-model particle a monoenergetic recoil. We show that this new scenario is presently allowed, which is surprising (perhaps a "minor miracle"). However, it can be systematically tested by novel analyses in present and near-term experiments.

Boosted Dark Matter Interpretation of the XENON1T Excess

“…Finally, we highlight that our BDM signals enjoy a daily modulation. Such a unique feature can be used to distinguish the signal proposed here from various backgrounds, as well as many other new physics interpretations of this excess [22][23][24][25]. Furthermore, the phase and the amplitude of the modulation can be used to extract crucial information about the BDM, e.g.…”

Dark Matter and the XENON1T electron recoil excess

“…Since DM exists, it is interesting to study whether the Xenon1T anomaly can be explained in some DM scenario. A narrow peak in the recoil energy E R can be provided by absorption of a light bosonic DM particle [1,12] or by DM DM e → DM e semi-absorption [13]. Scatterings of DM particles provide a broader structure, but cold DM particles are too slow, even when taking into account a Maxwellian-like tail of their velocity dis-tribution around or above the cut-off due to the escape velocity from the Milky Way, 0.0015 < v esc < 0.002 [14] in natural units.…”

Xenon1T excess from electron recoils of non-relativistic Dark Matter

“…Ref. [7]) suffer of LEE and thus lower their statistical preference with respect to the Standard Model.…”