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Two opposite parity dipole sequences (DB I and DB II) in 142Eu have been investigated using the Indian National Gamma Array (INGA), and heavy-ion induced fusion-evaporation reaction, 116Cd(31P, 5n) at ELab = 148 MeV. The Configurations of these bands are assigned on the basis of tilted axis cranking covariant density functional theory (TAC-CDFT) calculations. The measured B(M1) and B(E2) rates of the DB I and DB II, have been well reproduced within the shears mechanism with the principal axis cranking model (SPAC) calculations leading to the conclusion that these bands have been based on the shears mechanism. The large B(E1) transition rates between DB I and DB II indicate the existence of octupole correlation in 142Eu that has also been corroborated through microscopic multidimensionally-constrained covariant density functional theory (MDC-CDFT) calculations. Thus, the present investigation leads to the novel observation of the presence of octupole correlation between two shears band. Keywords: Lifetime measurement, Tilted axis rotation, Principal axis rotation, Octupole correlation, 142Eu

Lifetimes of the states in the quadrupole structure in 143Eu have been measured using the Doppler shift attenuation method and the parity of the states in the sequence has been firmly identified from polarization measurements using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B(E2) with spin, along with increasing J(2)/B(E2) values before the band crossing, conclusively establish the origin of these states as arising from antimagnetic rotation. The abrupt increase in the B(E2) values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may possibly indicate the crossing of different shears configurations resulting in the re-opening of a shears structure. The results are reproduced well by numerical calculations within the framework of a semi-classical geometric model.