Majorana fermion dark matter in minimally extended left-right symmetric model

Abstract

Abstract We present a minimal extension of the left-right symmetric model based on the gauge group SU(3) c × SU(2) L × SU(2) R × U(1) B−L × U(1) X , in which a vector-like fermion pair (ζ L and ζ R ) charged under the U(1) B−L × U(1)X symmetry is introduced. Associated with the symmetry breaking of the gauge group SU(2) R × U(1) B−L × U(1) X down to the Standard Model (SM) hypercharge U(1) Y , Majorana masses for ζ L,R are generated and the lightest mass eigenstate plays a role of the dark matter (DM) in our universe by its communication with the SM particles through a new neutral gauge boson “X”. We consider various phenomenological constraints of this DM scenario, such as the observed DM relic density, the LHC Run-2 constraints from the search for a narrow resonance, and the perturbativity of the gauge couplings below the Planck scale. Combining all constraints, we identify the allowed parameter region which turns out to be very narrow. A significant portion of the currently allowed parameter region will be tested by the High-Luminosity LHC experiments.

Keywords

• Beyond Standard Model
• Cosmology of Theories beyond the SM
• GUT