arXiv subjects

Marek Zralek

Publications and source records attributed to Marek Zralek.

9 recordsLinked to original sources

arXiv2022

A method to explore flavor symmetries of the 3HDM and their implications on lepton masses and mixing

We present a method to identify symmetry groups of the Yukawa sector of the three-Higgs-doublet model and to determine the implication that the symmetry has on the lepton masses and mixing. The method can accommodate different hypotheses about the group representation assignments, and thus support the exploration of candidate symmetry groups. For one particular representation selection scheme we apply the computer-implemented method to scan all discrete groups of order less than 1035. It can be proven that none of these groups defines a flavor symmetry that implies masses and neutrino mixing angles consistent with the experimental lepton data, although several cases are found that are partially or approximately consistent.

hep-ph↗

arXiv2013

New Physics in Neutron Beta Decay

Limits on parameters describing physics beyond the Standard Model are presented. The most general Lorentz invariant effective Hamiltonian at the quark-lepton level involving vector, scalar and tensor operators has been used. The fits have been done using the most precise and up to date experimental data for correlation coefficients measured in free neutron beta decay as well as the Fierz term measured in superallowed Fermi decays.

nucl-ex↗

arXiv2012

Oscillation of Dirac and Majorana neutrinos from muon decay in the case of a general interaction

We analyse the possibility of distinguishing Dirac and Majorana neutrinos in future neutrino factory experiments in which neutrinos are produced in muon decay when, in addition to a vector type as in the SM, there are also scalar interactions. We check this possibility in an experiment with a near detector, where the observed neutrinos do not oscillate, and in a far detector, after the neutrino oscillations. Neglecting higher-order corrections, even neutrino observation in the near detector does not give a chance to differentiate their character. However, this possibility appears in the leading-order after the neutrino oscillations observed in far detector.

hep-ph↗

arXiv2012

Majorana neutrino mass matrix with CP symmetry breaking

From the new existing data with not vanishing theta13 mixing angle we determine the possible shape of the Majorana neutrino mass matrix. We assume that CP symmetry is broken and all Dirac and Majorana phases are taken into account. Two possible approaches "bottom-up" and "top down" are presented. The problem of unphysical phases is examined in detail.

hep-ph↗

arXiv2012

Physics Beyond Standard Model in Neutron Beta Decay

Limits from neutron beta decay on parameters describing physics beyond the Standard Model are presented. New Physics is described by the most general Lorentz invariant effective Hamiltonian involving vector, scalar and tensor operators and Standard Model fields only. Two-parameter fits to the decay parameters measured in free neutron beta decay have been done, in some cases indicating rather big dependence of the results on g_A/g_V ratio of nucleon form factors at zero four-momentum transfer.

hep-ph↗

arXiv2010

50 Years of Neutrino Physics

Some important topics from history of neutrino physics over the last fifty years are discussed. History of neutrinos is older, at 4th December 2010 it will be eightieth anniversary of the "neutrino birth". In that day W. Pauli wrote the famous letter to participants of the physics conference at Tubingen with the suggestion that "there could exist in the nuclei electrically neutral particle". We will concentrate mostly on the 50 years of neutrino history just to show the long tradition of the Zakopane Theoretical School.

hep-ph↗

arXiv2010

Neutrino production states and NSI

The problems of neutrino production states, prepared to the oscillation process, in the case of non standard interactions, are briefly discussed. Quantum neutrino states are determined from the dynamics of a production process. We show, that even in models where only left-handed neutrinos are introduced, the standard adopted procedure is valid only approximately. Entanglement between neutrino masses or between masses, flavour and spins cause, that their quantum states are mixed.

hep-ph↗

arXiv2007

Neutrino production states in oscillation phenomena - are they pure or mixed?

General quantum mechanical states of neutrinos produced by mechanisms outside the Standard Model are discussed. The neutrino state is described by the Maki-Nakagawa-Sakata-Pontecorvo unitary mixing matrix only in the case of relativistic neutrinos and Standard Model left-handed charge current interaction. The problem of Wigner spin rotation caused by Lorentz transformation from the rest production frame to the laboratory frame is considered. Moreover, the mixture of the neutrino states as a function of their energy and parameters from the extension of the Standard Model are investigated. Two sources of mixture, the appearance of subdominant helicity states, and mass mixing with several different mixing matrices are studied.

hep-ph↗

arXiv2005

Conditions for detecting CP violation via neutrinoless double beta decay

Neutrinoless double beta decay data together with information on the absolute neutrino masses obtained from the future KATRIN experiment and/or astrophysical measurements give a chance to find CP violation in the lepton sector with Majorana neutrinos. We derive and discuss necessary conditions which make discovery of such CP violation possible for the future neutrino oscillation and mass measurements data.

hep-ph↗