Can we overcome the neutrino floor at high masses?

Abstract

The neutrino floor is a barrier in the parameter space of weakly interacting massive particles (WIMPs) below which discovery is impeded due to an almost irreducible background of neutrinos. Directional gas time projection chambers could discriminate against Solar neutrinos, relevant for WIMP masses 10 GeV, but would require prohibitively large volumes to go beyond the neutrino floor due to atmospheric neutrinos for masses 100 GeV. Here we combine all potential methods of subtracting the neutrino background to determine how much of this difficult to reach, but wellmotivated, parameter space it is feasible to reach. Most notably, we quantify whether a proposed directional signal in xenon and argon experiments called "columnar recombination" can help in this task. We find that even if the strength of this effect is amplified beyond current experimental results, the quantity of directional information contained in the recombination signal is too low to realistically discriminate against the atmospheric neutrino background. Instead, exploiting future complementarity with neutrino experiments such as DUNE will be the most practical means to push direct WIMP searches below the neutrino floor.

Exploring the Origin of Supermassive Black Holes with Coherent Neutrino Scattering

“…The extent to which CEνNS inhibits DM searches has been discussed extensively in the literature within the context of an irreducible neutrino background constituting a "neutrino floor" (e.g. [36,[59][60][61]). This question is often posed in the following manner: What exposure is required in order for an experiment to identify a particular DM candidate (with a well-defined mass and scattering cross section) at the statistical confidence level of Xσ (where X is often taken to be 3)?…”

Detecting CNO solar neutrinos in next-generation xenon dark matter experiments

“…For spin-independent dark matter-nucleus interactions, the nuclear recoil spectrum from a ∼ 6 GeV dark matter particle with cross section 10 −45 cm 2 mimics the spectrum from the 8 B component of the solar neutrino flux. The detailed sensitivity to solar neutrinos has been the subject of several studies, from the perspective of both a neutrino signal and a background to dark matter detection [1,2,[8][9][10][11]. For atmospheric neutrinos, a ∼ 100 GeV dark matter particle with cross section 10 −48 cm 2 will mimic the recoil spectrum from atmospheric neutrinos.…”

Constraining Light Mediators via Detection of Coherent Elastic Solar Neutrino Nucleus Scattering

“…The CEνNS detection has not only provided a unique probe to the nuclear neutron density distributions [6][7][8][9][10][11], but also offered a precision test of the physics beyond the Standard Model (SM), including the weak mixing angle [12,13], the neutrino electromagnetic properties [14][15][16], the nonstandard neutrino interactions [17][18][19][20][21] and the light mediators [22][23][24][25]. On the other hand, the observation of the CEνNS process have important implications on the neutrino floor [26][27][28][29][30][31] in the Dark Matter (DM) direct detection and the observation of astrophysical neutrino fluxes from the supernovae [32][33][34][35][36][37], the collapsing supermassive stars [38] and the primordial black holes [39]. In addition to the observation at spallation neutron sources [40,41], there are also intensive interests in the CEνNS detection from man-made reactor neutrinos [42][43][44][45].…”