Complementary studies of T=2 {sup 30}Al and the systematics of intruder states

Journal Article · Sat Mar 15 04:00:00 EDT 2008 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.77.034305· OSTI ID:21189823

Hinners, T A; Tripathi, Vandana; Tabor, S L; Volya, A; Bender, P C; Hoffman, C R; Lee, Sangjin; Perry, M; Mantica, P F; Davies, A D; Liddick, S N; Mueller, W F; Stolz, A; Tomlin, B E ^[1]

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1. Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States)

Low-spin states were studied in {sup 30}Al following the {beta} decay of {sup 30}Mg produced in the fragmentation of 140-MeV/AMU {sup 48}Ca. Analysis of the {beta}-{gamma} and {beta}-{gamma}-{gamma} coincidences revealed a new 1{sup +} state at 2413 keV, confirmation of the level scheme, and a more accurate half-life measurement of 315(6) ms for the {sup 30}Mg ground state. Higher-spin states were investigated in the reaction of {sup 14}C on {sup 18}O at 22 MeV. Protons and deuterons were detected in a segmented E-{delta}E Si telescope in coincidence with one or two {gamma} rays in the FSU Ge detector array. A comparison of the resulting level and decay scheme with predictions of the sd shell model shows good agreement with all but six of the states in both excitation energy and {gamma}-decay branching ratios. The root-mean-square deviations in energy of these states using the older USD and newer USDA and USDB interactions were 265, 176, and 173 keV, respectively. The remaining six states are well described as 4{sup -} to 7{sup -} states, similar in relative energy to those in {sup 28}Al but shifted down by about 1200 keV. These states also agree well with the predictions of shell-model calculations using the WBP interaction. A comparison of the lowest 4{sup -} states in even A Na, Al, and P isotopes shows a systematic decrease in energy with increasing N and with decreasing Z. The energies of the 4{sup -} states are almost identical in nuclei with the same N-Z values.

• OSTI ID: 21189823
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 3 Vol. 77; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALUMINIUM 28
ALUMINIUM 30
BETA DECAY
BRANCHING RATIO
CALCIUM 48
CARBON 14
COMPARATIVE EVALUATIONS
DEUTERONS
ENERGY RANGE
EXCITATION
FRAGMENTATION
GAMMA DECAY
GAMMA RADIATION
GE SEMICONDUCTOR DETECTORS
GROUND STATES
HALF-LIFE
MAGNESIUM 30
OXYGEN 18
SHELL MODELS
SPIN