Related papers: A viable $L_e-L_\mu$ model with $\mu\to e$ violati…
We propose a two-loop induced Zee-Babu type neutrino mass model at the TeV scale. Although there is no dark matter candidate in the original Zee-Babu model, that is contained in our model by introducing an unbroken discrete $Z_2$ symmetry.…
We present two recent developments on lepton flavour violation in the MSSM. 1) The supersymmetric seesaw mechanism can be realized through the exchange of heavy SU(2)_W-triplet states, rather than `right-handed' neutrinos. In this scenario…
Global analysis of neutrino oscillation data slightly favors normal mass ordering. In this work, we investigate an extended scalar sector that naturally gives rise to a type I + II seesaw mechanism after spontaneous symmetry breaking and…
Charged lepton flavor violation arises in the Standard Model Effective Field Theory at mass dimension six. The operators that induce neutrinoless muon and tauon decays are among the best constrained and are sensitive to new-physics scales…
It is known that the model based on U(1)$_{L_\mu-L_\tau}$ gauge symmetry can explain not only the discrepancy between the measured value of muon $g-2$ and the theoretical prediction, but also the structure of the neutrino mass and mixings.…
By extending the standard gauge group to $SU(3)_c \times SU(2)_L \times U(1)_Y \times U(1)_X$ with $X$ charges carried only by the third family we accommodate the LEP measurement of $R_b$ and predict a potentially measurable discrepancy in…
The inclusion of an additional $U(1)$ gauge symmetry is a common feature in many extensions of the Standard Model, revealing the intricate connections between particle physics and cosmology. The $L_{\mu} - L_{\tau}$ model stands as a…
Standard Model may allow an extended gauge sector with anomaly-free flavored gauge symmetries, such as $L_{i} - L_{j}$, $B_{i} - L_{j}$, and $B - 3L_{i}$, where $i,j=1,2,3$ are flavor indices. We investigate phenomenological implications of…
We develop a minimal and fully anomaly-free realization of a universal leptophilic $U(1)'_{\ell}$ gauge symmetry, under which all Standard-Model leptons carry a common charge while quarks remain neutral. Gauge consistency is restored by…
The quartic scalar coupling $\lambda_5$ term, which violates the lepton-number by two units in the Ma-model, is phenomenologically small when the model is applied to the lepton-flavor violation (LFV) processes. In order to dynamically…
The small neutrino mass observed in neutrino oscillations is nicely explained by the seesaw mechanism. Rich phenomenology is generally expected if the heavy neutrinos are not much heavier than the electroweak scale. A model with this…
The proposed work is an extension of the Standard Model, where we have introduced two gauge symmetries, i.e., $U(1)_{B-L}$ and $U(1)_{L_e-L_\mu}$ to study neutrino phenomenology, muon, and electron $(g-2)$ as well as leptogenesis using the…
The difference between baryon number B and lepton number L is the only anomaly-free global symmetry of the Standard Model, easily promoted to a local symmetry by introducing three right-handed neutrinos, which automatically make neutrinos…
We construct simple renormalizable extensions of the standard model where the leading baryon number violating processes have $\Delta B = \pm \Delta L = -2$. These models contain additional scalars. The simplest models contain a color…
A broad class of supersymmetric extensions of the standard model predict a Z' vector boson whose mass is naturally in the range 250 GeV < M_Z' < 2 TeV. To avoid unacceptably large mixing with the Z, one requires either a discrete tuning of…
The present work introduces two possible extensions of the Standard Model Higgs sector. In the first case, the Zee-Babu type model for the generation of neutrino mass is augmented with a scalar triplet and additional singly charged scalar…
We show that lepton number violating muon decays, \mu^+ -> e^+ + \nu_e-bar + \nu_i-bar (i=e, \mu or \tau), can consistently explain the neutrino anomaly reported by the LSND experiment. Two effective operators in the Standard Model are…
A new anomaly-free gauged $U(1)_\ell$ lepton-number model is studied. Two standard model lepton generations acquire the same but oppositive sign $U(1)_\ell$ charges, while four exotic chiral leptons cancel the anomalies of the remaining…
A recent model of dark energy and dark matter was proposed, involving a new gauge group $SU(2)_Z$ whose coupling grows strong at a scale $\Lambda_Z \sim 10^{-3} eV$, a result which is obtained from a simple assumption that its initial value…
The singly charged $SU(2)_L$ singlet scalar is one of the very interesting new particles, as it can generate neutrino masses at loop level, produce contributions to various flavour observables. We study the possibility of detecting this…