Evidence of antimagnetic rotation in an odd-odd nucleus: The case of 142Eu

Abstract

The present Rapid Communication reports conclusive evidence for an antimagnetic rotational band in the odd-odd $^{142}\mathrm{Eu}$ nucleus. The parity of the states of a quadrupole sequence in this nucleus is identified firmly from polarization measurements using the Indian National Gamma Array, and lifetimes of some of the states in the same structure are measured using the Doppler-shift attenuation method. The decreasing trends of the deduced quadrupole transition strength $B(E2)$ with spin in the sequence along with the increasing ${J}^{(2)}/B(E2)$ values conclusively establish the origin of these states as arising from antimagnetic rotation. The results are well reproduced by numerical calculations within the framework of a semiclassical geometric model.