Nuclear deformation and the two neutrino double-β decay in ^(124,126)Xe,^(128,130)Te, ^(130,132)Ba and ¹⁵⁰Nd isotopes

The two neutrino double beta decay of $^{124,126}$Xe,$^{128,130}$Te, $ ^{130,132}$Ba and $^{150}$Nd isotopes is studied in the Projected Hartree-Fock-Bogoliubov (PHFB) model. Theoretical 2$\nu $ $\beta^{-}\beta ^{-}$ half-lives of $^{128,130}$Te, and $^{150}$Nd isotopes, and 2$\nu \beta^{+}\beta^{+}$, 2$\nu $ $\beta^{+}EC$ and 2$\nu $ $ECEC$ for $ ^{124,126}$Xe and $^{130,132}$Ba nuclei are presented. Calculated quadrupolar transition probabilities B(E2: $0^+\to 2^+$), static quadrupole moments and $g$ factors in the parent and daughter nuclei reproduce the experimental information, validating the reliability of the model wave functions. The anticorrelation between nuclear deformation and the nuclear transition matrix element $M_{2\nu} $ is confirmed.