| |
Record |
Links |
|
Author  |
Escrig, S. et al; Morales, A.I. |
|
| |
Title |
Persistence of the Z=28 shell gap in A=75 isobars: Identification of a possible (1/2(-)) μs isomer in Co-75 and beta decay to Ni-75 |
Type |
Journal Article |
| |
Year |
2021 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
| |
Volume |
103 |
Issue |
6 |
Pages |
064328 - 12pp |
|
| |
Keywords |
|
|
| |
Abstract |
Background: The evolution of shell structure around doubly magic exotic nuclei is of great interest in nuclear physics and astrophysics. In the 'southwest' region of Ni-78, the development of deformation might trigger a major shift in our understanding of explosive nucleosynthesis. To this end, new spectroscopic information on key close-lying nuclei is very valuable. Purpose: We intend to measure the isomeric and beta decay of Co-75, with one-proton and two-neutron holes relative to Ni-78, to access new nuclear structure information in Co-75 and its beta-decay daughters Ni-75 and Ni-74. Methods: The nucleus Co-75 is produced in relativistic in-flight fission reactions of U-238 at the Radioactive Ion Beam Factory in the RIKEN Nishina Center. Its isomeric and f decay are studied exploiting the BigRIPS and EURICA setups. Results: We obtain partial beta-decay spectra for Ni-75 and Ni-74, and report a new isomeric transition in Co-75. The energy [E-gamma = 1914(2) keV] and half-life [t(1/2) = 13(6) μs] of the delayed gamma ray lend support for the existence of aJ(pi) = (1/2(-)) isomeric state at 1914(2) keV. A comparison with PFSDG-U shell-model calculations provides a good account for the observed states in Ni-75, but the first calculated 1/2(-) level in Co-75, a prolate K = 1/2 state, is predicted about 1 MeV below the observed (1/2(-)) level. Conclusions: The spherical-like structure of the lowest-lying excited states in Ni-75 is proved. In the case of Co-75, the results suggest that the dominance of the spherical configurations over the deformed ones might be stronger than expected below Ni-78. Further experimental efforts to discern the nature of the J(pi) = (1/2(-)) isomer are necessary. |
|
| |
Address |
[Escrig, S.; Morales, A., I] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46071 Valencia, Spain, Email: Samuel.Escrig@csic.es; |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2469-9985 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000669040500001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
4887 |
|
| Permanent link to this record |
