Effect of nuclear quadrupole moments on parity nonconservation in atoms
AbstractNuclei with spin I≥1 have a weak quadrupole moment which leads to tensor contribution to the parity nonconserving interaction between nuclei and electrons. We calculate this contribution for atoms of current experiment interest Yb+, Fr, and Ra+. We have also performed order of magnitude estimates and found strong enhancement of the weak quadrupole effects due to the close levels of opposite parity in many lanthanoids (e.g., Nd, Gd, Dy, Ho, Er, Pr, Sm) and Ra. Another possibility is to measure the parity-nonconservation (PNC) transitions between the hyperfine components of the ground state of Bi. Since nuclear weak charge is dominated by neutrons this opens a way of measuring quadrupole moments of neutron distribution in nuclei.