Right-handed neutrino pair production via second-generation leptoquarks

TL;DR

This paper explores how second-generation leptoquarks can produce right-handed neutrino pairs at the LHC, offering a new way to probe these particles and their couplings, with detailed analysis of production channels and detection prospects.

Contribution

It introduces a comprehensive study of LQ-induced right-handed neutrino production, including pair, single, and t-channel processes, in the inverse seesaw framework, filling a gap in experimental searches.

Findings

Potential for significant RHN production via LQ decays and t-channel exchange.

Analysis of monolepton and dilepton final states for detection.

Estimated discovery reach at the high-luminosity LHC.

Abstract

No direct experimental constraints exist on Leptoquark (LQ) couplings with quarks and right-handed neutrinos (RHNs). If a LQ dominantly couples to RHNs, it can leave unique signatures at the LHC. The RHNs can be produced copiously from LQ decays as long as they are lighter than the LQs. LQ-induced RHN production has never been searched for in experiments. This channel can act as a simultaneous probe for RHNs and LQs that dominantly couple to RHNs. In this paper, we consider all possible charge-$2/3$ and $1/3$ scalar and vector LQs that dominantly couple to second-generation quarks and RHN. We study the pair and single productions of TeV-scale LQs and their subsequent decay to sub-TeV RHNs, realised in the inverse seesaw framework. We also consider RHN pair production through a $t$-channel LQ exchange. The single LQ production and $t$-channel contributions can be significant for large LQ-RHN-quark couplings. We systematically combine events from these processes leading to a pair of RHNs plus jets to study the prospects of LQ-assisted RHN pair production. We analyse the monolepton and opposite-sign dilepton final states and estimate the discovery reach at the high-luminosity LHC.