Orateur
Dr
Javier Menéndez
(Technical University Darmstadt)
Description
Neutrinoless double beta (0nbb) decay is a unique process because, if
detected, it will imply the Majorana nature of neutrinos. Moreover,
once an experimental lifetime will be measured, with the nuclear
matrix elements (NMEs) very important information about the hierarchy
an absolute masses of the neutrinos will be known.
Therefore, a reliable calculation of the NMEs is crucial. Those can be
obtained with the Shell Model (SM) for most 0nbb decay candidates,
which lie in nuclear mass regions where the SM is able to give a very
good spectroscopic description.
I will present some details of these calculations, including the
pairing and deformation effects on the NMEs.
I will then explore the problem of the value of the axial-vector
coupling g_A, which needs to be quenched in Gamow-Teller and
two-neutrino double beta decay calculations, using weak currents based
on chiral effective field theory (chiral EFT).
This theory also gives nuclear forces that can be used in nuclear
structure calculations.
Author
Dr
Javier Menéndez
(Technical University Darmstadt)