gamma-ray linear polarization measurements and (g(9/2))(-3) neutron alignment in Ru-91

Creative Commons License

Zheng Y., de France G., Clement E., Dijon A., Cederwall B., Wadsworth R., ...More

PHYSICAL REVIEW C, vol.87, no.4, 2013 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 87 Issue: 4
  • Publication Date: 2013
  • Doi Number: 10.1103/physrevc.87.044328
  • Journal Name: PHYSICAL REVIEW C
  • Journal Indexes: Science Citation Index Expanded, Scopus


Linear polarization measurements have been performed for gamma rays in Ru-91 produced with the Ni-58(Ar-36,2p1n gamma)Ru-91 reaction at a beam energy of 111 MeV. The EXOGAM Ge clover array has been used to measure the gamma-gamma coincidences, gamma-ray linear polarization, and gamma-ray angular distributions. The polarization sensitivity of the EXOGAM clover detectors acting as Compton polarimeters has been determined in the energy range 0.3-1.3 MeV. Several transitions have been observed for the first time. Measurements of linear polarization and angular distribution have led to the firm assignments of spin differences and parity of high-spin states in Ru-91. More specifically, calculations using a semiempirical shell model were performed to understand the structures of the first and second (21/2(+)) and (17/2(+)) levels. The results are in good agreement with the experimental data, supporting the interpretation of the nonyrast (21/2(+)) and (17/2(+)) states in terms of the J(max) and J(max) - 2 members of the seniority-three nu(g(9/2))(-3) multiplet. DOI: 10.1103/PhysRevC.87.044328