Given the particle content of the standard model without and with a right-handed neutrino, the requirement that all anomalies cancel singles out a set of possible global symmetries which can be ...gauged. I review this topic and propose a new gauge symmetryB — 3LT in the context of the minimal standard model consisting of the usual three families of quarks and leptons plus just onevR. The many interesting phenomenological consequences of this hypothesis are briefly discussed.
Leptoquark-Higgs interactions induce mixing between leptoquark states with different chiralities once the electro-weak symmetry is broken. In such LQ models Majorana neutrino masses are generated at ...1-loop order. Here we calculate the neutrino mass matrix and explore the constraints on the parameter space enforced by the assumption that LQ-loops explain current neutrino oscillation data. LQs will be produced at the LHC, if their masses are at or below the TeV scale. Since the fermionic decays of LQs are governed by the same Yukawa couplings, which are responsible for the non-trivial neutrino mass matrix, several decay branching ratios of LQ states can be predicted from measured neutrino data. Especially interesting is that large lepton flavour violating rates in muon and τ final states are expected. In addition, the model predicts that, if kinematically possible, heavier LQs decay into lighter ones plus either a standard model Higgs boson or a Z0/W± gauge boson. Thus, experiments at the LHC might be able to exclude the LQ mechanism as explanation of neutrino data.
Provider: - Institution: - Data provided by Europeana Collections- Göttingen, Georg-August Universität, Diss., 2015- All metadata published by Europeana are available free of restriction under the ...Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
The hypothesis of Lorentz violation in the neutrino sector has intrigued scientists for the last two to three decades. A number of theoretical arguments support the emergence of such violations, ...first and foremost for neutrinos, which constitute the “most elusive” and “least interacting” particles known to mankind. It is of obvious interest to place stringent bounds on the Lorentz-violating parameters in the neutrino sector. In the past, the most stringent bounds have been placed by calculating the probability of neutrino decay into a lepton pair, a process made kinematically feasible by Lorentz violation in the neutrino sector, above a certain threshold. However, even more stringent bounds can be placed on the Lorentz-violating parameters if one takes into account, additionally, the possibility of neutrino splitting, i.e., of neutrino decay into a neutrino of lower energy, accompanied by “neutrino-pair Čerenkov radiation.” This process has a negligible threshold and can be used to improve the bounds on Lorentz-violating parameters in the neutrino sector. Finally, we take the opportunity to discuss the relation of Lorentz and gauge symmetry breaking, with a special emphasis on the theoretical models employed in our calculations.
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