First isomeric quadrupole moment measured in fragmentation reactions: The case of {sup 61}Fe{sup m}(9/2{sup +})

• Published in: Physical review. C, Nuclear physics Nuclear physics, 2007-05, Vol.75 (5)
• Main Authors: Vermeulen, N., Yordanov, D. T., Neyens, G., Chamoli, S. K., Hass, M., Goldring, G., Singh, B. S. Nara, Daugas, J. M., Delaroche, J. P., Girod, M., Goutte, H., Morel, P., Perru, O., Peru, S., Roig, O., Balabanski, D. L., Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 1784 Sofia, Oliveira-Santos, F. de, Grevy, S., Perrot, L., Stefan, I.
• Format: Article
• Language: English
• Subjects: ELECTRONS; FRAGMENTATION; IRON 61; KEV RANGE 100-1000; MEAN-FIELD THEORY; MONOCRYSTALS; NEUTRONS; NICKEL 64; NUCLEAR PHYSICS AND RADIATION PHYSICS; QUADRUPOLE MOMENTS; S QUARKS; SPIN
• ISSN: 0556-2813; 1089-490X
• DOI: 10.1103/PHYSREVC.75.051302

This paper demonstrates the feasibility of quadrupole moment measurements on isomeric levels populated in projectile fragmentation reactions. The neutron-rich {sup 61}Fe(9/2{sup +}) [E*= 861 keV, T{sub 1/2}= 239(5) ns] isomer was produced and spin aligned by the intermediate energy fragmentation of a {sup 64}Ni beam and implanted in a Cd single crystal. Its spectroscopic quadrupole moment |Q{sub s}|=41(6) e fm{sup 2} agrees with mean-field based calculations using the finite-range Gogny force, suggesting a moderately deformed shape characterized by an intrinsic charge quadrupole moment Q{sub 0}=-85 e fm{sup 2} or Q{sub 0}=+115 e fm{sup 2}. The present measurement paves the way for future determinations of isomeric quadrupole moments in more exotic nuclei.