Towards Superheavies: Spectroscopy of 94 < Z < 98, 150 < N < 154 Nuclei

• Main Authors: Chowdhury, P., Hota, S. S., Qiu, Y, Ahmad, I., Carpenter, M. P., Greene, J. P., Janssens, R. V. F., Khoo, T. L., Kondev, F. G., Lauritsen, T., Lister, C. J., Seweryniak, D., Zhu, S.
• Format: Conference Proceeding
• Language: English
• Subjects: Angular momentum; Nuclear reactions; Nuclear structure; Nuclei (nuclear physics)
• ISSN: 2100-014X; 2101-6275; 2100-014X
• DOI: 10.1051/epjconf/201612302003

The heaviest nuclei where excitations above the ground state can be studied lie near Z ~ 100. These nuclear structure studies are important testing grounds for theoretical models that aim to describe superheavy nuclei. To study the highest neutron orbitals (150 ≤ N ≤ 154), we have populated high angular momentum states in a series of Pu (Z = 94), Cm (Z = 96) and Cf (Z = 98) nuclei, via inelastic and transfer reactions, with heavy beams on long-lived radioactive actinide targets. Multiple collective excitation modes and structures were identified, and their configurations deduced. Quasiparticle alignments are mapped, with odd-A band structures helping identify specific orbital contributions via blocking arguments. Higher-order multipole shapes are observed to play a significant role in disentangling competing neutron and proton alignments. The N > 152 data provide new perspectives on physics beyond the N = 152 sub-shell gap.