Spin of Neon-21

The spin of neon-21 has been shown to be $\frac{3}{2}$ by the atomic beam magnetic resonance method utilizing the metastable $2p^{5}3s{}_{}{}^3{}_{}{}^{}P_2^{}{}_{}{}^{}$ state of neon. The assignment is made from a comparison of Zeeman frequencies in neon-20 and neon-21 at the same magnetic field.