Neutrinoless double Beta-decay in See-saw Mechanism

In the standard model the total lepton number is conserved.Thus the neutrinoless double beta decay ,in which lepton number violated by 2 units is a probe of Physics beyond the Standard Model.Here we first discuss about the Standard Model and then we discuss about the Seesaw mechanism to generate the small Majorana mass of the neutrinos , in which the lepton number is violated by 2 units. After a brief summary we discuss then about the neutrino masses and mixing i.e.Cabbibo-Kobayashi- Maskawa ( CKM ) matrix and PMNS matrix, normal and inverted hierarchy , the absolute scale of neutrino masses ,effective Majorana mass.After brief discussion we plot the graphs for normal and inverted hierarchy and find out the range of the normal and inverted spectrum and we discuss a little bit about the Majorana phases and we plot the graphs between two Majorana phases.In the next portion we discuss about the theory of neutrinoless double beta decay.In this case at first we calculate the matrix element, then the decay rate of the neutrinoless double beta decay and finally we calculate the half life-time of this process. Then we plot the half life-time vs lightest mass graphs for normal and inverted hierarchy and make some conclusion

Neutrino mass and charged lepton flavor violation in an extended left-right symmetric model

We consider an $U(1)_{L_\mu -L_\tau}$ extended left-right symmetric gauge theory where the neutrino masses are generated through inverse seesaw mechanism. In this model the muon $(g-2)$ anomaly is accounted for by the mediation of $Z_{\mu\tau}$, the gauge boson of $U(1)_{L_\mu - L_\tau}$ symmetry. The symmetries of the model require the light neutrino mass matrix to have a particular two-zero texture, which leads to non-trivial constraints in the minimum neutrino mass. In addition, the model predicts observable charged lepton flavor violation in $\mu-\tau$ sector.Comment: 21 pages, 2 figures, 2 tables, Version accepted in Nucl. Phys.

Collider Signatures of WRW_R boson in the Alternative Left-Right Model

Alternative Left-Right Models offer an attractive option to left-right models. Emerging from $E_6$ grand unification, these models are consistent with light scalars which do not induce flavour-changing neutral currents due to the presence of exotic quarks. Here we investigate the signature at the LHC collider of the charged $W_R$ boson, which can be lighter than in left-right models. We include constraints from collider data and show that $W_R$ can be produced in pairs, or in conjunction with a light charged Higgs boson. The final decay products involve leptons or jets. We explore all production and decay possibilities and indicate which ones are most promising to be observed at the colliders. Our analysis shows that signals of $W_R$ bosons can be observed at the LHC at 27 TeV, some for lower luminosity, and under most favourable conditions, even at 13 TeV.Comment: 10 figures, 10 table

Dark matter in the Alternative Left Right model

Abstract The Alternative Left-Right Model is an attractive variation of the usual Left-Right Symmetric Model because it avoids flavour-changing neutral currents, thus allowing the additional Higgs bosons in the model to be light. We show here that the model predicts several dark matter candidates naturally, through introduction of an R-parity similar to the one in supersymmetry, under which some of the new particles are odd, while all the SM particles are even. Dark matter candidates can be fermionic or bosonic. We present a comprehensive investigation of all possibilities. We analyze and restrict the parameter space where relic density, direct and indirect detection bounds are satisfied, and investigate the possibility of observing fermionic and bosonic dark matter signals at the LHC. Both the bosonic and fermionic candidates provide promising signals, the first in LHC at 300 fb −1, the second at higher luminosity, 3000 fb −1. Signals from bosonic candidates are indicative of the presence of exotic d′ quarks, while fermionic candidates imply the existence of charged Higgs bosons, all with masses in the TeV region