The Decay of the T=1 Isospin Triplet in A=12 Systems: IV. The Energy Dependence of the Asymmetry Coefficients αᵦ_∓ of the Beta-Ray Angular Distribution in Aligned ¹²B and ¹²N and the Induced Pseudotensor Interaction

Abstract

The asymmetry parameters αᵦ_∓ of the beta-ray emitted from aligned ¹²B and ¹²N are evaluated as a function of the energy. The agreement with experimental differential data is excellent for both αᵦ₋ (W) and αᵦ₊ (W). This work confirms, using available nuclear model information, that no induced pseudotensor (IPT) interaction is required for a correct theoretical interpretation of the data. An upper limit for the IPT coupling constant f_T is determined from a simultaneous fit of αᵦ₋ (W) and αᵦ₊ (W).