We calculate nuclear spin-dependent parity non-conserving $E1$-amplitudes for optical transition $6p_{ 1/2,F} -> 6p_{ 3/2,F'}$ and for hyperfine transition $6p_{ 1/2,F} -> 6p_{ 1/2,F'}$ in Tl. Experimental limit on the former amplitude placed by Vetter et al. [PRL, 74, 2658 (1995)] corresponds to the anapole moment constant $\kappa_a = -0.26 \pm 0.27$. Experiment on the hyperfine transition can give direct measurement of the spin-dependent amplitude, because spin-independent amplitude turns to zero.
Categories: physics.atom-ph