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تسجيل مستخدم جديدExploring $0 ubetabeta$ and Leptogenesis in the Alternative Left-Right Model
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We investigate the possibility of neutrinoless double beta decay ($0 ubetabeta$) and leptogenesis within the Alternative Left-Right Model (ALRM). Unlike the usual left-right symmetric model, ALRM features a Majorana right-handed neutrino which does not carry any charge. Further, in this picture the down-type quark and the charged leptons receive mass through the additional left-handed scalar field, rather than the usual doublet. Together, these features conspire to generate significant contributions to the $0 ubetabeta$ through vector-scalar ($WH$) mediation. For moderate masses of the relevant charged Higgs boson ($M_{H_1^pm}sim 200$ GeV), the half-life of $T_{frac{1}{2}}^{WH}$ is $sim 3times 10^{26}~{rm yrs}$ for both the case of $^{76}$Ge and $^{136}$Xe, well within the sensitivity expected by future experiments. Invoking the resonant leptogenesis, CP violation arising from the right-handed neutrino decay could be the required order to generate the correct baryogenesis, $epsilonsim 10^{-6}$, for small Dirac phases and without any fine tuning.
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