Description
This analysis addresses the viability of \textit {Dirac phase leptogenesis}, in a scenario where the light Majorana neutrinos acquire masses by the inverse seesaw (ISS) mechanism. We show that, a successful leptogenesis in the ISS driven by the Dirac CP phase can be achieved with the involvement of an unorthodox form of the rotational matrix $R = e^{i{\bf A}} \,\,\,(e^{{\bf A}})$ in the Casas-Ibarra parametrisation. This particular form of $R$ turns out to be an artefact in explaining the observed baryon asymmetry of the Universe in a pure ISS scenario. We report that, with these choices of rotational matrix an adequate amount of lepton asymmetry can be obtained subject to a sizeable range of the $R$ matrix parameter space. We have shown analytically how the scale of the right handed neutrinos are decided by the choice of the $R$ matrix parameter space in a generic ISS scenario. Following which we perform the relevant analysis for the branching ratios of the LFV decay channel $\mu \rightarrow e\gamma$. Finally we have reported the existence of an accessible parameter space for both leptogenesis and lepton flavor violation which is otherwise unprecedented in the ISS. The appealing feature of these forms of $R$ matrix have been emerged in extracting the ISS parameter space to have an appropriate control over the lepton asymmetry generation and the amount of washout, to finally account for the observed baryon asymmetry of the Universe. We also report here that, for $R = e^{i{\bf A}}$ choice leptogenesis demands the Dirac CP phase ($\delta _{\rm CP}$ to oscillate around $\pi/2$, although for the later choice the constraint on $\delta^{\rm CP}$ is much relaxed.
