Probe of the shell crossing at A = 40 via beta decay: Experiment and theory

Journal Article · Mon Sep 01 04:00:00 EDT 1986 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.34.1031· OSTI ID:5312387

Warburton, E K; Alburger, D E; Becker, J A; Brown, B A; Raman, S

The ..beta../sup -/ decays of /sup 35/P, /sup 37/S, /sup 38/S, and /sup 38/Cl were studied both experimentally and via shell-model calculations. The four decaying nuclei were formed by bombardment of 81% enriched /sup 36/S by triton and deuteron beams. Gamma-ray spectroscopy was carried out with Ge detectors, either bare or surrounded by a Compton suppression NaI(Tl) shield. One new Gamow-Teller decay was observed in /sup 35/P decay, and one new first-forbidden decay was observed in /sup 38/S decay. Otherwise ..gamma..-ray measurements of E/sub ..gamma../ and I-/sub ..gamma../ (and limits on I/sub ..gamma../ for unobserved transitions) were improved significantly over previous results. Shell-model studies were undertaken in order to bring these beta decay results to bear on an understanding of the shell structure in the (sd) to (fp) transition region at A = 40. An interaction was constructed in the 1d/sub 5/2/, 1d/sub 3/2/, 2s/sub 1/2/, 1f/sub 7/2/, 1f/sub 5/2/, 1p/sub 3/2/, 1p/sub 1/2/ model space. This interaction started from the Wildenthal ''USD'' (sd) interaction and the van Hees-Glaudemans (fp) interaction, which were connected by the cross-shell Millener-Kurath interaction. Certain important two-body matrix elements and single-particle energies were adjusted to fit experimental binding energies in A = 40, 41, 42. This interaction was then used to calculate level spectra for the daughter nuclei /sup 35/S, /sup 37/Cl, /sup 38/Cl, and /sup 38/Ar as well as Gamow-Teller and unique first-forbidden beta decays leading to these nuclei. The techniques used in these relatively large scale calculations are discussed in detail, as are the results.

• Research Organization: Brookhaven National Laboratory, Upton, New York 11973
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5312387
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 34:3; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651422* -- Nuclear Properties & Reactions
A=20-38
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651423 -- Nuclear Properties & Reactions
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73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ARGON 38
ARGON ISOTOPES
BETA DECAY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY
BETA-MINUS DECAY RADIOISOTOPES
BINDING ENERGY
CHARGED-PARTICLE REACTIONS
CHLORINE 37
CHLORINE 38
CHLORINE ISOTOPES
DAUGHTER PRODUCTS
DAYS LIVING RADIOISOTOPES
DECAY
DEUTERON REACTIONS
ENERGY
ENERGY LEVELS
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
GAMMA SPECTROSCOPY
HOURS LIVING RADIOISOTOPES
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LIGHT NUCLEI
MATHEMATICAL MODELS
MINUTES LIVING RADIOISOTOPES
NUCLEAR MODELS
NUCLEAR REACTIONS
NUCLEI
NUCLEON-NUCLEON POTENTIAL
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
PARTICLE MODELS
PHOSPHORUS 35
PHOSPHORUS ISOTOPES
POTENTIALS
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
SHELL MODELS
SINGLE-PARTICLE MODEL
SPECTROSCOPY
STABLE ISOTOPES
SULFUR 35
SULFUR 36 TARGET
SULFUR 37
SULFUR 38
SULFUR ISOTOPES
TARGETS
TRITON REACTIONS