$Z'$ Portal Dark Matter in $B-L$ Scotogenic Dirac Model

TL;DR

This paper analyzes the phenomenology of $Z'$ portal scalar and Dirac fermion dark matter within a $B-L$ scotogenic Dirac model, exploring collider signatures, relic density, and detection prospects, especially near the resonance region.

Contribution

It introduces a $B-L$ scotogenic Dirac neutrino mass model with unconventional charges and thoroughly studies its dark matter phenomenology and experimental constraints.

Findings

Resonance region $M_{DM} \,\sim\, M_{Z'}/2$ is viable for dark matter.

Current data constrains TeV-scale dark matter in this model.

Future experiments can probe the parameter space near the resonance.

Abstract

In this paper, we perform a detail analysis on the phenomenology of $Z'$ portal scalar and Dirac fermion dark matter in $B-L$ scotogenic Dirac model. Unconventional $B-L$ charge $Q$ is assigned to the right-handed neutrino $\nu_R$ in order to realise scotogenic Dirac neutrino mass at one-loop level, where three typical value $Q=-\frac{1}{4},-4,\frac{3}{2}$ are chosen to illustrate. Observational properties involving dilepton signature at LHC, relativistic degrees of freedom $N_\text{eff}$, dark matter relic density, direct and indirect detections are comprehensively studied. Combined results of these observables for the benchmark scenarios imply that the resonance region $M_\text{DM}\sim M_{Z'}/2$ is the viable parameter space. Focusing on the resonance region, a scanning for TeV-scale dark matter is also performed to obtain current allowed and future prospective parameter space.