Revealing new structures in odd–odd 54Mn nucleus

• Published in: The European physical journal. A, Hadrons and nuclei Vol. 59; no. 10
• Main Authors: Basu, S., Mukherjee, G., Nandi, S., Nayak, S. S., Bhattacharyya, S., Bhattacharya, Soumik, Dar, Shabir, Das, Sneha, Basak, S., Kumar, D., Paul, D., Banerjee, K., Roy, Pratap, Manna, S., Kundu, Samir, Rana, T. K., Pandey, R., Chatterjee, S., Raut, R., Ghugre, S. S., Samanta, S., Banik, R., Karmakar, A., Chattopadhyay, S., Gupta, S. Das, Pallav, P., Rajbanshi, S., Ali, S., Pai, H.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 16.10.2023
• Subjects: Hadrons; Heavy Ions; Nuclear Fusion; Nuclear Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Regular Article – Experimental Physics
• ISSN: 1434-601X
• DOI: 10.1140/epja/s10050-023-01147-9

The excited states of odd–odd 54 Mn ( Z = 25 , N = 29 ) nucleus have been investigated using the fusion evaporation reaction 55 Mn( α , α n) 54 Mn at the beam energy of 34 MeV. A new and improved level scheme of 54 Mn has been proposed in this work with the placement of 22 new γ -ray transitions. Spin and parity (J π ) of most of the levels in the revised level scheme have been firmly assigned. The placement of some of the already known γ rays in the level scheme and J π assignments of some of the levels reported earlier have also been revised. The new level scheme, which has been extended up to ∼ 6 MeV, provides new insight and interesting structural aspects of the generation of high angular momentum in this odd–odd Mn isotope with neutron number ( N = 29 ) just above the N = 28 shell gap. Three octupole-phonon-coupled negative parity states have been identified for the first time in this nucleus. E 3 transitions have also been observed to decay from these states. Shell model calculations with two different interactions i.e. kb3gpn and gx1pn have been performed which well reproduced the low-lying, few-particle states but fail to reproduce the higher-lying multi-particle states. These higher-lying states have been understood as resulting from collective excitations. An oblate minimum obtained from the Total Routhian Surface calculations provides support to this conjecture.