A search for parity mixtures in nuclear states

Abstract

The gamma radiation emitted from nuclear states which are polarized by beta decay can show a 90 degree asymmetry if parity conservation in nuclear states does not hold strictly. A beta-gamma angular-correlation experiment yields linearly the quantity R F , where F is the relative amplitude of the irregular wave functon with respect to the regular one and R is the matrix-element ratio of the gamma transitions. The measurement are performed with the beta-gamma decays of A 41 → K 41, Xe 133 → Cs 133, and Lu 177 → Hf 177 and result in the following upper limits for F : 6 × 10 − for A 41, 2 × 10 −4 to 8 × 10 −6 for Xe 133, and 3 × 10 −3 for Lu 177.