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Related papers: Limits on Neutrino Mixing with new Heavy Particles

200 papers

A limit on the tau neutrino mass is obtained using all the $Z^{0} \to \tau^{+} \tau^{-}$ data collected at LEP by the DELPHI detector between 1992 and 1995. In this analysis events in which one of the taus decays into one charged particle,…

High Energy Physics - Experiment · Physics 2019-08-16 Davide Perego

We reconsider neutrino decay as an explanation for atmospheric neutrino observations. We show that if the mass-difference relevant to the two mixed states \nu_\mu and \nu_\tau is very small (< 10^{-4} eV^2), then a very good fit to the…

High Energy Physics - Phenomenology · Physics 2009-09-25 V. Barger , J. G. Learned , P. Lipari , M. Lusignoli , S. Pakvasa , T. J. Weiler

Evidence of massive neutrinos in the pi --> e nu decay spectrum was sought with the background pi --> mu --> e decay chain highly suppressed. Upper limits (90% C.L.) on the neutrino mixing matrix element |U_ei|^2 in the neutrino mass region…

Many experiments are being planned to measure the neutrino mixing parameter $\theta_{13}$ using reactor as well as accelerator neutrino beams. In this note, the theoretical significance of a high precision measurement of this parameter is…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. N. Mohapatra

We study the framework of $U(1)_X$ models with kinetic mixing and/or mass mixing terms. We give general and exact analytic formulas and derive limits on a variety of $U(1)_X$ models that induce new physics contributions to neutrino-electron…

High Energy Physics - Phenomenology · Physics 2018-11-02 Manfred Lindner , Farinaldo S. Queiroz , Werner Rodejohann , Xun-Jie Xu

Possible maximal mixing seen in the oscillations of the atmospheric neutrinos has led to postulate of a $\mu$-$\tau$ symmetry which interchanges $\nu_\mu$ and $\nu_\tau$. We argue that such symmetry need not be special to neutrinos but can…

High Energy Physics - Phenomenology · Physics 2008-11-26 Anjan S. Joshipura

Sterile neutrinos with masses $\sim 0.1$ eV or higher would play an important role in astrophysics and cosmology. We explore possible signatures of such sterile neutrinos at long baseline experiments. We determine the neutrino conversion…

High Energy Physics - Phenomenology · Physics 2008-11-26 Amol Dighe , Shamayita Ray

Elastic neutrino-electron scattering represents a powerful tool to investigate key neutrino properties. In view of the recent results released by the LUX-ZEPLIN collaboration, we provide a first determination of the limits achievable on the…

High Energy Physics - Phenomenology · Physics 2023-03-03 M. Atzori Corona , W. M. Bonivento , M. Cadeddu , N. Cargioli , F. Dordei

We investigate the sensitivity of some weak processes to the simplest extension of the Standard Model with Majorana neutrinos mixing in the leptonic sector. Values for mixing angles and masses compatible with several experimental…

High Energy Physics - Phenomenology · Physics 2009-10-31 O. L. G. Peres , L. P. Freitas , R. Zukanovich Funchal

The combined requirements, of (i) a natural solution to the fermion mass hierarchy problem and (ii) an explanation of both the atmospheric and solar neutrino problems, lead to an essentially unique picture of neutrino masses and mixing…

High Energy Physics - Phenomenology · Physics 2009-10-30 C. D. Froggatt , M. Gibson , H. B. Nielsen

General lowest order perturbations to hermitian squared mass matrices of leptons are considered away from the tribimaximal (TBM) limit in which a weak flavor basis with mass diagonal charged leptons is chosen. The three measurable TBM…

High Energy Physics - Phenomenology · Physics 2015-06-22 Biswajoy Brahmachari , Probir Roy

Naturally small neutrino masses can arise in some grand unified models. The mechanism of neutrino mass generation in these models typically requires the existence of neutral heavy leptons. We study the low-energy phenomenology of these new…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ivan Melo

We present a new constraint on a lepton mixing matrix $V$ from lepton-flavor violating (LFV) processes in supersymmetric standard models with massive neutrinos. Here, we assume Yukawa-coupling unification $f_{\nu 3}\simeq f_{\rm top}$, in…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. Sato , K. Tobe , T. Yanagida

The discovery of new, flavor-dependent neutrino interactions would provide compelling evidence of physics beyond the Standard Model. We focus on interactions generated by the anomaly-free, gauged, abelian lepton-number symmetries,…

High Energy Physics - Phenomenology · Physics 2023-09-13 Sanjib Kumar Agarwalla , Mauricio Bustamante , Sudipta Das , Ashish Narang

Light sterile neutrinos can be excited by oscillations with active neutrinos in the early universe. Their properties can be constrained by their contribution as extra-radiation, parameterized in terms of the effective number of neutrino…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Alessandro Mirizzi , Gianpiero Mangano , Ninetta Saviano , Enrico Borriello , Carlo Giunti , Gennaro Miele , Ofelia Pisanti

The combined effect of neutrino flavor oscillations and neutrino magnetic moment on neutrino-electron scattering is discussed. It is shown, that if the tau neutrino has a (large) magnetic moment and can oscillate into a neutrino of another…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. N. Gninenko

New physics beyond the Standard Model can lead to extra matter effects on neutrino oscillation if the new interactions distinguish among the three flavors of neutrino. In a previous paper, we argued that a long-baseline neutrino oscillation…

High Energy Physics - Phenomenology · Physics 2007-08-07 Minako Honda , Yee Kao , Naotoshi Okamura , Alexey Pronin , Tatsu Takeuchi

If the atmospheric and the solar neutrino problem are both explained by neutrino oscillations, and if there are only three light neutrinos, then all mass-squared differences between the neutrinos are known. In such a case, existing…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sven Bergmann , Yuval Grossman

A new flavor changing electron neutrino interaction with matter would always dominate the nu_e oscillation probability at sufficiently high neutrino energies. Being suppressed by theta_{13}, the energy scale at which the new effect starts…

High Energy Physics - Phenomenology · Physics 2009-11-07 Mario Campanelli , Andrea Romanino

Light hypothetical particles with masses up to $\mathcal{O}(100)\ {\rm MeV}$ can be produced in the core of supernovae. Their subsequent decays to neutrinos can produce a flux component with higher energies than the standard flux. We study…

High Energy Physics - Phenomenology · Physics 2024-07-12 Kensuke Akita , Sang Hui Im , Mehedi Masud , Seokhoon Yun