R-parity Violating Supersymmetric Explanation of the Anomalous Events at ANITA

TL;DR

This paper proposes a beyond Standard Model explanation for ANITA's anomalous upgoing events using R-parity violating supersymmetry, involving long-lived binos produced via resonant slepton/squark interactions, consistent with existing constraints.

Contribution

It introduces a novel RPV SUSY model with GeV-scale binos to explain ANITA's events, addressing the survival of particles through Earth and reconciling with IceCube data.

Findings

ANITA events can be explained with GeV-scale binos and specific RPV couplings.

Anisotropic neutrino flux is required for the model to fit observations.

The model is testable at LHC, Belle II, ANITA-IV, and IceCube.

Abstract

The ANITA balloon experiment has observed two EeV-energy, upgoing events originating from well below the horizon. This is puzzling, because (i) no Standard Model (SM) particle is expected to survive passage through Earth at such energies and incident angles, and (ii) no such events were reported by IceCube. In this paper, we address both these issues by invoking a beyond SM interpretation of the EeV events as due to the decay of a long-lived bino in the R-parity violating (RPV) supersymmetry. In particular, a TeV-scale slepton/squark can be resonantly produced through the interaction of the EeV neutrino with electrons/nucleons inside Earth, that decays to a light, long-lived bino, which survives the propagation through Earth matter before decaying back to neutrinos, leptons and/or quarks, thus producing upgoing air showers in the atmosphere near ANITA. We find that the ANITA events can be explained with a GeV-scale bino and ${\cal O}(0.1)$ RPV couplings, which are consistent with all existing high and low-energy constraints. We also find that an isotropic neutrino flux is inadequate for a beyond the SM explanation of this kind, and an anisotropic flux must be invoked. Finally, we also address the apparent tension of these observations with IceCube. Various aspects of our interpretation are testable in the near future at different frontiers, such as by the LHC, Belle II, ANITA-IV and IceCube.