Accelerating Composite Dark Matter Discovery with Nuclear Recoils and the Migdal Effect

Abstract

Large composite dark matter states source a scalar binding field that, when coupled to Standard Model nucleons, provides a potential under which nuclei recoil and accelerate to energies capable of ionization, radiation, and thermonuclear reactions. We show that these dynamics are detectable for nucleon couplings as small as g n ∼ 10 −17 at dark matter experiments, where the greatest sensitivity is attained by considering the Migdal effect. We also explore Type-Ia supernovae and planetary heating as possible means to discover this type of dark matter.

Scattering searches for dark matter in subhalos: neutron stars, cosmic rays, and old rocks

“…[17], of higher mass composite DM in Refs. [64][65][66][67][68][69][70], and similar sensitivities with ancient minerals in Refs. [71][72][73].…”

Can sub-GeV dark matter coherently scatter on the electrons in the atom?

“…Then the ionized electrons drift into the gaseous xenon layer at the top of the detector in presence of an external electric field, which produces a proportional scintillation light, namely the S2 signal. In the theoretical studies, such ionization signals can come from the DM-electron scattering [6][7][8][9][10][11][12][13][14][15][16][17] or the DM-nucleus scattering through the Migdal effect that originates from the non-instantaneous movement of electron cloud during a nuclear recoil event [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35].…”

Direct Detection of Spin-Dependent Sub-GeV Dark Matter via Migdal Effect

“…Then the ionized electrons drift into the Gaseous Xenon layer at the top of the detector in presence of an external electric field, and then collide with the xenon atoms, which produces a proportional scintillation light, namely the S2 signal. In theory, such ionization signals can come from the DM-electron scattering [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] or the DM-nucleus scattering through the Migdal effect that originates from non-instantaneous movement of electron cloud during a nuclear recoil event [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39]. The Migdal scattering is usually sub-dominant to the conventional nuclear scattering, but can take place in a very low energy nuclear recoil, which has been used to improve the sensitivity of the DM-nucleus interactions in the low DM mass region [40][41][42].…”