Double-Cascade Events from New Physics in Icecube

Shedding new light on sterile neutrinos from XENON1T experiment

The XENON1T collaboration recently reported the excess of events from recoil electrons, possibly giving an insight into new area beyond the Standard Model (SM) of particle physics. We try to explain this excess by considering effective interactions between the sterile neutrinos and the SM particles. In this paper, we present an effective model based on one-particle-irreducible interaction vertices at low energies that are induced from the SM gauge symmetric four-fermion operators at high energies. The effective interaction strength is constrained by the SM precision measurements, astrophysical and cosmological observations. We introduce a novel effective electromagnetic interaction between sterile neutrinos and SM neutrinos, which can successfully explain the XENON1T event rate through inelastic scattering of the sterile neutrino dark matter from Xenon electrons. We find that sterile neutrinos with masses around 90 keV and specific effective coupling can fit well with the XENON1T data where the best fit points preserving DM constraints and possibly describe the anomalies in other experiments.

New Opportunities at the Next-Generation Neutrino Experiments (Part 1: BSM Neutrino Physics and Dark Matter

With the advent of a new generation of neutrino experiments which leverage high-intensity neutrino beams for precision neutrino oscillation parameter and for CP violation phase measurements, it is timely to explore physics topics beyond the standard neutrino-related physics. Given that beyond the standard model (BSM) physics phenomena have been mostly sought at high-energy regimes, such as the LHC at CERN, the exploration of BSM physics in neutrino experiments will enable complementary measurements at the energy regimes that balance that of the LHC. This is in concert with new ideas for high-intensity beams for fixed target and beam-dump experiments world-wide. The combination of the high intensity beam facilities and large mass detectors with highly precise track and energy measurements, excellent timing resolution, and low energy thresholds will help make BSM physics reachable even in low energy regimes in accelerator-based experiments and searches for BSM phenomena from cosmogenic origin. Therefore, it is conceivable that BSM topics could be the dominant physics topics in the foreseeable future. In this spirit, this paper provides a review of the current theory landscape theory in neutrino experiments in two selected areas of the BSM topics - dark matter and neutrino related BSM - and summarizes the current results from existing neutrino experiments for benchmark. This paper then provides a review of upcoming neutrino experiments and their capabilities to set the foundation for potential reach in BSM physics in the two themes. One of the most important outcomes of this paper is to ensure theoretical and simulation tools exist to perform studies of these new areas of physics from the first day of the experiments, such as DUNE and Hyper-K. Tasks to accomplish this goal, and the time line for them to be completed and tested to become reliable tools in a timely fashion are also discussed.