Dark matter searches for monoenergetic neutrinos arising from stopped meson decay in the Sun

Abstract

Dark matter can be gravitationally captured by the Sun after scattering off solar nuclei. Annihilations of the dark matter trapped and accumulated in the centre of the Sun could result in one of the most detectable and recognizable signals for dark matter. Searches for high-energy neutrinos produced in the decay of annihilation products have yielded extremely competitive constraints on the spin-dependent scattering cross sections of dark matter with nuclei. Recently, the low energy neutrino signal arising from dark-matter annihilation to quarks which then hadronize and shower has been suggested as a competitive and complementary search strategy. These high-multiplicity hadronic showers give rise to a large amount of pions which will come to rest in the Sun and decay, leading to a unique sub-GeV neutrino signal. We here improve on previous works by considering the monoenergetic neutrino signal arising from both pion and kaon decay. We consider searches at liquid scintillation, liquid argon, and water Cherenkov detectors and find very competitive sensitivities for few-GeV dark matter masses.

Dark matter in the Sun: scattering off electrons vs nucleons

“…Since then, this is one of the existing strategies to indirectly detect DM, which is in turn complementary to DM direct searches, given that in both cases the signal would be proportional to the DM elastic scattering cross section. Indeed, numerous studies have evaluated the prospects of detection of the potential high-energy neutrino flux and of that of neutrinos in the O(10-100) MeV range [72][73][74][75] using neutrino detectors/telescopes [76][77][78][79][80][81][82][83][84][85][86][87][88][89]. All these works have focused on DM-nucleon interactions.…”

New Dark Matter Search Strategies at DUNE

“…The blue band represents the combined sensitivities from the electron-only and muon-only analysis. Also shown are previous sensitivities from DUNE [19], Super-K [20], and Hyper-K [21,22] when directional information is not used, as found in [4]. We also show the exclusion regions based on IceCube data [23,24] computed with nulike [25, 23,26], on PICO-60 [27,28] and on PICO-2L [29], and the region favored by DAMA/LIBRA (at 90%/3σ/5σ/7σ CL) [30].…”

“…Typically, one focuses on searching for a continuous spectrum of high-energy neutrinos, produced by dark matter annihilation, above the atmospheric neutrino background. In this proceedings contribution, we will describe a different possibility [4,5]; we will find that there is a broad class of models in which dark matter annihilation in the Sun produces sub-GeV monoenergetic neutrinos, and find that neutrino detectors with excellent energy resolution (such as DUNE) can resolve this type of line signal. We will also find that detectors with good angular resolution can resolve the direction of the incoming neutrino, despite its low energy.…”

Enhanced Neutrino Emissivities in Pseudoscalar-mediated Dark Matter Annihilation in Neutron Stars

“…A DM particle will be gravitationally captured by the Sun if, in scattering against solar nuclei, it falls below the local escape velocity. This accumulation mechanism can lead to a local stellar DM density higher than that of the galactic halo where it resides, potentially providing us with an opportune region in which to search for visible signatures (Kouvaris 2008;Rott et al 2015;Vincent et al 2015). Additionally, low density environments in solartype stars could yield interesting features in the neutrino channel (Palomares-Ruiz & Pascoli 2008;Aartsen et al 2017).…”