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We discuss the possible origin of non-zero reactor mixing angle $\theta_{13}$and Dirac CP phase $\delta_{CP}$ in the leptonic sector from a combination oftype I and type II seesaw mechanisms. Type I seesaw contribution to neutrinomass matrix is of tri-bimaximal (TBM) type which gives rise to vanishing$\theta_{13}$ leaving the Dirac CP phase undetermined. If the Dirac neutrinomass matrix is assumed to take the diagonal charged lepton type structure, sucha TBM type neutrino mass matrix originating from type I seesaw corresponds toreal values of Dirac Yukawa couplings in the terms $Y_{ij} \bar{L_i} H N_j$.This makes the process of right handed heavy neutrino decay into a lightneutrino and Higgs $(N \rightarrow \nu H)$ CP preserving ruling out thepossibility of leptogenesis. Here we consider the type II seesaw term as thecommon origin of non-zero $\theta_{13}$ and $\delta_{CP}$ by taking it as aperturbation to the leading order TBM type neutrino mass matrix. First, wenumerically fit the type I seesaw term by taking oscillation as well ascosmology data and then compute the predictions for neutrino parameters afterthe type II seesaw term is introduced. We consider a minimal structure of thetype II seesaw term and check whether the predictions for neutrino parameterslie in the $3\sigma$ range. We also compute the predictions for baryonasymmetry of the Universe by considering type II seesaw term as the only sourceof CP violation and compare it with the latest cosmology data.

Type II Seesaw Origin of Non-zero $\theta_{13}, \delta_{CP} $ and Leptogenesis