Post-Sphaleron baryogenesis and $n-\bar{n}$ oscillation in non-SUSY SO(10) GUT with gauge coupling unification and proton decay

Abstract

Post-sphaleron baryogenesis, a fresh and profound mechanism of baryogenesis accounts for the matter-antimatter asymmetry of our present universe in a framework of Pati-Salam symmetry. We attempt here to embed this mechanism in a non-SUSY SO(10) grand unified theory by reviving a novel symmetry breaking chain with Pati-Salam symmetry as an intermediate symmetry breaking step and as well to address post-sphaleron baryogenesis and neutron-antineutron oscillation in a rational manner. The Pati-Salam symmetry based on the gauge group $SU(2{)}_L\times SU(2{)}_R\times SU(4{)}_C$ is realized in our model at $10^5-10^6$ GeV and the mixing time for the neutron-antineutron oscillation process having $\Delta B=2$ is found to be ${\tau }_{n-\bar{n}}\simeq 10^8-10^{10}\text{mbox}secs$ with the model parameters which is within the reach of forthcoming experiments. Other novel features of the model includes low scale right-handed $W_R^{\pm }$, $Z_R$ gauge bosons, explanation for neutrino oscillation data via gauged inverse (or extended) seesaw mechanism and most importantly TeV scale color sextet scalar particles responsible for observable $n-\bar{n}$ oscillation which can be accessible to LHC. We also look after gauge coupling unification and estimation of proton life-time with and without the addition of color sextet scalars.

Comments: v2: 28 pages, matches the version to be published in European Physical Journal C