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Structure of 30Mg explored via in-beam γ-ray spectroscopy

Journal Article · · Physical Review C
 [1];  [2];  [3];  [4];  [5];  [5];  [4];  [4];  [4];  [6];  [4];  [3];  [7];  [4];  [5];  [4];  [8];  [4];  [5];  [5] more »;  [4];  [4];  [9];  [3];  [10];  [4];  [5] « less
  1. Univ. of Tokyo, Saitama (Japan); Michigan State University
  2. Univ. of Tokyo (Japan); Central Michigan Univ., Mount Pleasant, MI (United States); Michigan State Univ., East Lansing, MI (United States); Instituto de Estructura de la Materia, Madrid (Spain)
  3. Univ. of Tokyo, Saitama (Japan)
  4. Michigan State Univ., East Lansing, MI (United States)
  5. Central Michigan Univ., Mount Pleasant, MI (United States)
  6. Univ. of Guelph, ON (Canada)
  7. Technische Univ. Darmstadt (Germany)
  8. Central Michigan Univ., Mount Pleasant, MI (United States); Michigan State Univ., East Lansing, MI (United States)
  9. Univ. of Surrey (United Kingdom)
  10. Japan Atomic Energy Agency, Ibaraki (Japan); Univ. of Tokyo, Saitama (Japan)
+ Show Author Affiliations
In the island of inversion, ground states of neutron-rich sd-shell nuclei exhibit strong admixtures of intruder configurations from the fp shell. The nucleus 30Mg, located at the boundary of the island of inversion, serves as a cornerstone to track the structural evolution as one approaches this region. Spin-parity assignments for excited states in 30Mg, especially negative-parity levels, have yet to be established. In the present work, the nuclear structure of 30Mg was investigated by in-beam gamma-ray spectroscopy mainly focusing on firm spin-parity determinations. High-intensity rare-isotope beams of 31Mg, 32Mg, 34Si, and 35P bombarded a Be target to induce nucleon removal reactions populating states in 30Mg. Gamma rays were detected by the state-of-the-art gamma-ray tracking array GRETINA. For the direct one-neutron removal reaction, final-state exclusive cross sections and parallel momentum distributions were deduced. Multi-nucleon removal reactions from different projectiles were exploited to gain complementary information. With the aid of the parallel momentum distributions, an updated level scheme with revised spin-parity assignments was constructed. Spectroscopic factors associated with each state were also deduced. Results were confronted with large-scale shell-model calculations using two different effective interactions, showing excellent agreement with the present level scheme. Furthermore, a marked difference in the spectroscopic factors indicates that the full delineation of the transition into the island of inversion remains a challenge for theoretical models.
Research Organization:
Michigan State Univ., East Lansing, MI (United States)
Sponsoring Organization:
National Science Foundation (NSF); USDOE Office of Science (SC), Nuclear Physics (NP)
Grant/Contract Number:
AC02-05CH11231; SC0020451
OSTI ID:
1712950
Journal Information:
Physical Review C, Journal Name: Physical Review C Journal Issue: 5 Vol. 102; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

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Related Subjects

20 ≤ A ≤ 38
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
Direct reactions
Energy levels & level densities
Nuclear fragmentation
Nuclear spin & parity
Nuclear structure & decays
Radioactive beams
Shell model
Spectroscopic factors & electromagnetic moments