Beta decay properties of [sup 67,68]Se and the astrophysical [ital rp]-process path

Journal Article · Mon Aug 01 00:00:00 EDT 1994 · Physical Review, C (Nuclear Physics); (United States)

DOI:https://doi.org/10.1103/PhysRevC.50.1180· OSTI ID:7015146

Baumann, P; Bounajma, M; Huck, A; Klotz, G; Knipper, A; Walter, G ^[1]; Marguier, G ^[2]; Richard-Serre, C ^[3]; Ravn, H ^[4]; Hagebo, E; Hoff, P; Steffensen, K ^[5]

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1. Centre de Recherches Nucleaires, Universite Louis Pasteur, 67037 Strasbourg (France) the Isolde Collaboration, CERN, 1211 Geneva 23 (Switzerland)
2. Institut de Physique Nucleaire, Universite Claude Bernard, 69622 Villeurbanne (France) the Isolde Collaboration, CERN, 1211 Geneva 23 (Switzerland)
3. Institut National de Physique Nucleaire et de Physique des Particules, 75781 Paris (France) the Isolde Collaboration, CERN, 1211 Geneva 23 (Switzerland)
4. CERN, PPE Division/Isolde, 1211 Geneva 23 (Switzerland)
5. Department of Chemistry, University of Oslo, Blindern, 0315 Oslo (Norway) the Isolde Collaboration, CERN, 1211 Geneva 23 (Switzerland)

The [sup 67]Se and [sup 68]Se isotopes near the proton drip line were produced by spallation of zirconium with 600 MeV protons at CERN. Beta decay properties were determined for the first time using the selectivity of molecular ion beams at the on-line mass separator ISOLDE. Chemically selective production was obtained through separation of the molecular ion COSe[sup +]. The half-lives of [sup 67]Se and [sup 68]Se were measured as 107[plus minus]35 ms and 35.5[plus minus]0.7 s respectively. From [beta]-[gamma] and [gamma]-[gamma] coincidences, and conversion-electron measurements, a decay scheme was obtained for [sup 68]Se. For the [sup 68]As ground state and several excited states, spin and parity are unambiguously determined from [beta]-decay rates and electromagnetic multipolarity assignments. In addition to the strong Fermi branch between the mirror ground states of [sup 67]Se and [sup 67]As [[ital J][sup [pi]]=(5/2)[sup [minus]],[ital T][sub [ital z]]=[plus minus]1/2], a GT branch to an excited state in [sup 67]As is observed. Implications of [sup 67]Se and [sup 68]Se properties in the [ital rp]-process path are considered.

• OSTI ID: 7015146
• Journal Information: Physical Review, C (Nuclear Physics); (United States), Vol. 50:2; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ARSENIC 68
ENERGY LEVELS
SELENIUM 68
BETA-PLUS DECAY
SELENIUM ISOTOPES
CORRELATIONS
GAMMA CASCADES
HALF-LIFE
MEV RANGE 100-1000
PARITY
PROTON REACTIONS
SPALLATION
SPIN
ZIRCONIUM 80
ANGULAR MOMENTUM
ARSENIC ISOTOPES
BARYON REACTIONS
BETA DECAY
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CHARGED-PARTICLE REACTIONS
DAYS LIVING RADIOISOTOPES
DECAY
ENERGY RANGE
EVEN-EVEN NUCLEI
HADRON REACTIONS
INTERMEDIATE MASS NUCLEI
ISOTOPES
MEV RANGE
MINUTES LIVING RADIOISOTOPES
NUCLEAR CASCADES
NUCLEAR DECAY
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
ODD-ODD NUCLEI
PARTICLE PROPERTIES
RADIOISOTOPES
YEARS LIVING RADIOISOTOPES
ZIRCONIUM ISOTOPES
663210* - Ground-State Radioactivity- (1992-)
663220 - Electromagnetic Transitions- (1992-)
663550 - Nuclear Mass Ranges- A=59-89- (1992-)