Imprints of Left-Right Symmetry breaking in Gravitational Wave Spectroscopy: A non-minimal case study

Abstract

We investigate the dynamics of cosmological phase transition in the framework of a non-minimal version of Left-Right symmetric gauge model. At a high energy scale, this framework having the symmetry $SU(2)_L \otimes SU(2)_{R} \otimes U(1)_R \otimes U(1)_L$, is stemmed out from the Grand Unifying group $E_6$. Rich scalar sector of this model offers interesting opportunity for studying first order phase transition which can be the source of stochastic gravitational waves. Taking into account the theoretical and experimental constraints applicable to this model, we look for benchmark parameters where first order phase transition could be observed during the breaking of $SU(2)_{R} \otimes U(1)_R \otimes U(1)_L$ down to $U(1)_Y$, at an energy scale of tens of TeVs or higher. Our investigation reveals the possibility of strong first order phase transition over a large region of parameter space. We also discuss the production of stochastic gravitational waves arising from such strong first order phase transition. Our results present clear, testable predictions that fall directly within the sensitivity bands of ongoing and next-generation gravitational-wave observatories like LISA, DECIGO, AEDGE and $μ$ARES.