Nukleárny seminár - Nițescu Ovidiu (28.4.2021)

v stredu 28.4.2021 o 14:00 hod. online formou

22. 04. 2021 15.35 hod.
Od: Jaroslav Staníček

Pozývame Vás na Nukleárny seminár Katedry jadrovej fyziky a biofyziky FMFI UK, Slovenskej fyzikálnej spoločnosti a Slovenskej nukleárnej spoločnosti 

 Dr. Nițescu Ovidiu 

Názov: Improved description of the 2νββ-decay

Termín: 28.4.2021, 14:00 hod., MS Teams 

Several next-generation double-beta experiments with a variety of suitable isotopes are in different stages of construction or preparation and planning. Their main goal is the observation of 0νββ-decay. An important by-product of these experimental searches will be a precise measurement of the 2νββ-decay with high statistics. The study of this process is important on its own and represents a research program with many important questions waiting for an answer. There is a possibility of exploring new physics beyond SM with 2νββ-decay. It covers the search for the right-handed neutrino interactions without having to assume their nature, neutrino self-interactions, sterile neutrinos with masses up to Q-value of the process, the bosonic neutrino component, violation of the Lorentz invariance, the 0νββ-decay with Majoron(s) emission and the quadruple-β decay. The 2νββ-decay also provides insights into the nuclear structure of nuclear systems under consideration, which can then be used in a reliable calculation of the nuclear matrix elements for 0νββ-decay, necessary to extract the particle physics parameters responsible for the lepton number violation or in fixing the effective value of the axial-vector coupling constant.

By considering the effect of lepton energies in the energy denominators of nuclear matrix elements, we present an improved formalism of the 2νββ-decay. The energy and angular distributions of the emitted electrons, which might offer clues of the fundamental properties and interactions of the neutrinos, are now presented with a free parameters theory. Those parameters can be determined experimentally through shape analyzes of the single and summed energy distribution and from the measurement of the angular correlation factor. Some possible applications of extended formalism are also discussed.