Complementarity of experiments in probing the non-relativistic effective theory of dark matter-nucleon interactions

Abstract

The non-relativistic effective theory of dark matter-nucleon interactions depends on 28 coupling strengths for dark matter spin up to 1/2. Due to the vast parameter space of the effective theory, most experiments searching for dark matter interpret the results assuming that only one of the coupling strengths is non-zero. On the other hand, dark matter models generically lead in the non-relativistic limit to several interactions which interfere with one another, therefore the published limits cannot be straightforwardly applied to model predictions. We present a method to determine a rigorous upper limit on the dark matter-nucleon interaction strength including all possible interferences among operators. We illustrate the method to derive model independent upper limits on the interaction strengths from the null search results from XENON1T, PICO-60 and IceCube. For some interactions, the limits on the coupling strengths are relaxed by more than one order of magnitude. We also present a method that allows to combine the results from different experiments, thus exploiting the synergy between different targets in exploring the parameter space of dark matter-nucleon interactions.

Enhanced prospects for direct detection of inelastic dark matter from a non-galactic diffuse component

“…The dotted lines represent the limits obtained considering the galactic dark matter (described by the SHM) as the only contribution to the dark matter flux, while the solid lines were obtained including also the contributions to the flux from the non-galactic diffuse component in the Solar System. In the upper left plot, we show the limits for a Majorana dark matter candidate in the "isoscalar" scenario, and in the upper right plot, the most conservative limit for the Majorana dark matter, without making assumptions on the coupling strengths, derived following the approach of [55]. Lastly, in the lower plot we show the limits for a scenario where the dark matter interacts with the nucleus via the exchange of a Z-boson.…”