Left-Right Symmetric Models at the High-Intensity Frontier

TL;DR

This paper evaluates the potential of the SHiP experiment to detect heavy neutrinos in Left-Right Symmetric models through meson decay searches, showing it surpasses other methods like neutrinoless double beta decay and LHC dilepton searches in the GeV mass range.

Contribution

It provides a detailed analysis of SHiP's sensitivity to heavy neutrinos in Left-Right Symmetric models, highlighting its advantages over existing experimental approaches.

Findings

SHiP can effectively probe heavy neutrinos in the GeV mass range.

Resonant enhancement occurs when heavy neutrinos are on-shell in meson decays.

SHiP outperforms neutrinoless double beta decay and LHC dilepton searches for certain parameter spaces.

Abstract

We study constraints on Left-Right Symmetric models from searches of semileptonic decays of $D$, $D_{s}$, $B$ mesons, mediated by heavy neutrinos $N$ with masses $m_N\sim $ GeV that go on their mass shell leading to a resonant enhancement of the rates. Using these processes we examine, as a function of $m_N$ and $M_{W_R}$, the physics reach of the recently proposed high-intensity beam dump experiment SHiP, which is expected to produce a large sample of $D_s$ mesons. We compare these results with the corresponding reach of neutrinoless double beta decay experiments, as well as like-sign dilepton searches with displaced vertices at the LHC. We conclude that the SHiP experiment has clear advantages in probing the Left-Right Symmetric models for heavy neutrinos in the GeV mass range.