Prospects for Indirect Detection of Sneutrino Dark Matter with IceCube

TL;DR

This paper assesses IceCube's ability to detect right-handed sneutrino dark matter via neutrino signals from the Sun, considering model constraints and different velocity distributions, finding potential detectability especially from the Sun.

Contribution

It introduces a detailed analysis of sneutrino dark matter detection prospects at IceCube within a $U(1)_{B-L}$ extended MSSM, highlighting the impact of velocity distributions on detection rates.

Findings

Muon event rates from the Sun can reach detectable levels (~100 km$^{-2}$ yr$^{-1}$).

Earth muon event rates are generally too small unless velocity distributions are modified.

Detection prospects depend strongly on velocity distribution assumptions and model parameters.

Abstract

We investigate the prospects for indirect detection of right-handed sneutrino dark matter at the IceCube neutrino telescope in a $U(1)_{B-L}$ extension of the MSSM. The capture and annihilation of sneutrinos inside the Sun reach equilibrium, and the flux of produced neutrinos is governed by the sneutrino-proton elastic scattering cross section, which has an upper bound of $8 \times 10^{-9}$ pb from the $Z^{\prime}$ mass limits in the $B-L$ model. Despite the absence of any spin-dependent contribution, the muon event rates predicted by this model can be detected at IceCube since sneutrinos mainly annihilate into leptonic final states by virtue of the fermion $B-L$ charges. These subsequently decay to neutrinos with 100% efficiency. The Earth muon event rates are too small to be detected for the standard halo model irrespective of an enhanced sneutrino annihilation cross section that can explain the recent PAMELA data. For modified velocity distributions, the Earth muon events increase substantially and can be greater than the IceCube detection threshold of 12 events $\mathrm{km}^{-2}$ $\mathrm{yr}^{-1}$. However, this only leads to a mild increase of about 30% for the Sun muon events. The number of muon events from the Sun can be as large as roughly 100 events $\mathrm{km}^{-2}$ $\mathrm{yr}^{-1}$ for this model.