Sterile Neutrinos at MAPP in the B-L Model

TL;DR

This paper explores the potential of the MAPP detector at MoEDAL to detect right-handed neutrinos via B-L gauge interactions, achieving sensitivities to very small active-sterile mixing angles.

Contribution

It introduces a novel search strategy for right-handed neutrinos at MAPP through B-L and Z boson portals, with sensitivity estimates near current experimental limits.

Findings

MAPP can detect active-sterile mixing as low as 10^{-12}

Sensitivity is comparable via B-L and SM Z boson portals

Effective mixing can be probed down to 0.002

Abstract

The possibility of searching for right-handed neutrinos at the MoEDAL's Apparatus for Penetrating Particles (MAPP) detector is investigated in this work. In particular, pair-production of right-handed (RH) neutrinos $N$ from either a $B-L$ gauge boson $Z'$, as well as Standard Model (SM) $Z$ boson are considered. Under a no-background assumption, we show that the MAPP detector can be sensitive to active-sterile neutrino mixing strengths as low as $V_{\mu N}^2 \approx 10^{-12}$ for multiple choices of $m_N / m_{Z'}$ values, when taking the $B-L$ gauge coupling $g_{B-L} = 10^{-3}$ near its current limit. The SM $Z$ boson portal can reach a similar sensitivity, when the effective mixing between the $B-L$ and SM gauge boson is $\alpha \approx 0.002$.