Searching for physics beyond the Standard Model in an off-axis DUNE near detector

Abstract

Next generation neutrino oscillation experiments like DUNE and T2HK are multi-purpose observatories, with a rich physics program beyond oscillation measurements. A special role is played by their near detector facilities, which are particularly well-suited to search for weakly coupled dark sector particles produced in the primary target. In this paper, we demonstrate this by estimating the sensitivity of the DUNE near detectors to the scattering of sub-GeV DM particles and to the decay of sub-GeV sterile neutrinos (“heavy neutral leptons”). We discuss in particular the importance of the DUNE-PRISM design, which allows some of the near detectors to be moved away from the beam axis. At such off-axis locations, the signal-to-background ratio improves for many new physics searches. We find that this leads to a dramatic boost in the sensitivity to boosted DM particles interacting mainly with hadrons, while for boosted DM interacting with leptons, data taken on-axis leads to marginally stronger exclusion limits. Searches for heavy neutral leptons perform equally well in both configurations.

Searches for new physics at SND@LHC

“…Depending on the model, there are various signatures of new physics in processes with LDM or mediators. Examples are: LDM scattering off electrons or protons (an incomplete list of studies is [15, [18][19][20][21][22][23][24][25][26][27][28][29]); rare neutrino scattering events induced by new physics, as the trident reaction ν + n → p + χ + l with missing transverse momentum [30,31], or the process ν + Z → ν + Z + l + l [32]; an excess of charged current (CC) ν τ events, such as in models with neutrinophilic mediators coupled exclusively to τ lepton flavor [33].…”

Extending the Reach of Leptophilic Boson Searches at DUNE and MiniBooNE with Bremsstrahlung and Resonant Production

“…Another result of our work is that the existing data collected in the beam dump mode of MiniBooNE [12] provides already competitive bounds. We note that experiments such as DUNE and MiniBooNE will have sensitivity to a variety of BSM physics, including heavy neutral leptons [13][14][15][16][17], axionlike particles [18,19], dark matter [15,[20][21][22][23][24][25][26], and millicharged particles [27]. Finally, we note that additional, complementary signatures of Z s can arise from modifications to the neutrino scattering cross section [28,29].…”

Light, Long-Lived $B-L$ Gauge and Higgs Bosons at the DUNE Near Detector

“…The DUNE capability, specifically using its gaseous argon near detector (immediately downstream of the liquid argon near detector) to identify final-states of particles decaying in flight has been detailed in Refs. [31,[42][43][44][45][46][47]. We will use the results of these works and consider that a background-free search for these final states is possible.…”