arXiv subjects

Adrian Palcu

Publications and source records attributed to Adrian Palcu.

22 records · Page 2Linked to original sources

arXiv2007

Conserving the lepton number $L_{e}-L_μ-L_τ$ in the exact solution of a 3-3-1 gauge model with right-handed neutrinos

In this paper we consider a plausible scenario with conserved lepton number \textbf{$L=L_{e}-L_μ-L_τ$} within the framework of the exact solution of a particular 3-3-1 gauge model. We discuss what are the consequences of conserving this global leptonic symmetry from the viewpoint of the neutrino mass matrix constructed via special Yukawa terms (involving tensor products among Higgs triplets). We prove that the actual experimental data can naturally be reproduced by our scenario since soft breaking terms with respect to this lepton symmetry are properly introduced. As a consequence, our solution predicts for the neutrino sector the correct mass splitting ratio ($Δm_{12}^{2}/Δm_{23}^{2}\simeq0.033$), the inverted mass hierarchy, the correct values for the observed mixing angles ($\sin^{2}θ_{23}\simeq0.5$ and $\sin^{2}θ_{12}=0.31$)and the absolute mass of the lightest neutrino ($m_{0}\sim0.001$eV)independent of the breakung scale of the model.

hep-ph↗

arXiv2006

Implementing Canonical Seesaw Mechanism in a 3-3-1 Gauge Model without Exotic Electric Charges

We prove that - even at a low TeV scale - the canonical seesaw mechanism can be naturally implemented in the exact solution of a particular 3-3-1 gauge model, since a very small alteration $ε$ in the parameter matrix of the Higgs sector is taken into account. Therefore, this new parameter can act as an appropriate mass source for neutrinos, while - due to the main parameter $a$ - all the previously achieved results in the exact solution of the model are recovered. Moreover, this mathematical artifice does separate the boson mass spectrum from the neutrino mass issue, hence giving more flexibility in tuning the model. Possible phenomenological results and their implications - such as dark matter plausible candidates that can occur - are also briefly discussed.

hep-ph↗

arXiv2006

Neutrino Mass Squared Differences in the Exact Solution of a 3-3-1 Gauge Model without Exotic Electric Charges

The mass splittings for the Majorana neutrinos in the exact solution of a particular 3-3-1 gauge model are computed here in detail. Since both $\sin^{2}θ_{13}\simeq0$ and the mass splittings ratio $r_Δ\simeq0.033$ are taken into account, the analytical calculations seem to predict an inverted mass hierarchy and a mixing matrix with a texture based on a very close approximation to the bi-maximal mixing. The resulting formulas for the mass squared differences can naturally accomodate the available data if the unique free parameter ($a$) gets very small values ($\sim10^{-15}$). Consequently, the smallness of the parameter requires (according to our method) a large breaking scale $<ϕ>\sim10^{6}-10^{7}$ TeV in the model. Hence, the results concerning the neutrino mass splittings may lead to a more precise tuning in the exact solution of the 3-3-1 model of interest, being able - at the same time - to recover all the Standard Model phenomenology and predict the mass spectrum of the new gauge bosons $Z^{\prime},X,Y$ in accordance with the actual data. The minimal absolute mass in the neutrino sector is also obtained - $m_{0}\simeq0.0035$ eV - in the case of our suitable approximation for the bi-maxcimal mixing.

hep-ph↗

arXiv2006

Neutrino mass as a consequence of the exact solution of 3-3-1 gauge models without exotic electric charges

The unjustly neglected method of exactly solving generalized electro-weak models - with an original spontaneous symmetry breaking mechanism based on the gauge group $SU(n)_{L}\otimes U(1)_{Y}$ - is applied here to a particular class of chiral 3-3-1 models. This procedure enables us - without resorting to any approximation - to express the boson mass spectrum and charges of the particles involved therein as a straightforward consequence of both a proper parametrization of the Higgs sector and a new generalized Weinberg transformation. We prove that the resulting values can be accommodated to the experimental ones just by tuning a sole parameter. Furthermore, if we take into consideration both the left-handed and right-handed components of the neutrino (included in a lepton triplet along with their corresponding left-handed charged partner) then we are in the position to propose an original method for the neutrino to acquire a very small but non-zero mass without spoiling the previously achieved results in the exact solution of the model. In order to be compatible with the existing phenomenological data, the range of that sole parameter imposes in our method a large order of magnitude for the VEV $<ϕ>\sim10^{6}$ TeV. Consequently, the new bosons of the model have to be very massive. PACS numbers: 14.60.St; 12.60.Cn; 12.60.Fr

hep-th↗