and mixing followed by super-WIMP dark matter phenomenology in section \[sec3\]. We finally conclude in section \[sec4\].

$A_4$ Model with TBM mixing {#sec:model}
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In this section we outline the flavour model based on non-Abelian discrete group $A_4$ augmented by a $Z_4$ symmetry for dark sector. A brief summary of $A_4$ group, its representations and product rules are given in appendix \[appen1\]. The particle content of the model, relevant for discussing the lepton sector and dark matter sector is shown in table \[tab:a\]. Apart from the SM lepton doublets and charged lepton singlets, there are three right handed neutrinos required for implementing the type I seesaw mechanism [@Minkowski:1977sc; @GellMann:1980vs; @Mohapatra:1979ia; @Schechter:1980gr]. In addition to the usual SM Higgs doublet, there exist three additional Higgs doublets required to generate Dirac mass term for neutrinos. There also exists two more scalar fields responsible for generating the desired right handed neutrino mass matrix and also to break the $A_4$ flavour symmetry spontaneously. Two more fields one scalar and one fermion, both charged under the $Z_4$ symmetry are included in order to achieve the desired DM phenomenology.

    Fields          $L_e, L_{\mu}, L_{\tau}$        $e_{{\mbox{\tiny$R$}}}, \mu_{{\mbox{\tiny$R$}}}, \tau_{{\mbox{\tiny$R$}}}$        $H$             $H_T$        $\phi_N$   $\xi$   $N_{R}$   $\psi$       $\eta$
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