Effect of the neutron quadrupole distribution in the TaO${}^{+}$ cation

Abstract

We estimate the effect of the tensor parity nonconserving (PNC) interaction in the ${}^{181}$TaO${}^{+}$ molecular cation. It can be used to probe the unknown quadrupole distribution of the neutrons inside the Ta nucleus. To this end, we evaluate the constant which characterizes this interaction using the relativistic Fock space coupled cluster theory for electronic structure modelling. The ${}^3{\Delta }_1$ state of the TaO${}^{+}$ cation which can be used to measure the PNC effect is found to be the ground one in agreement with the previous theoretical study.