Experimental study of {beta}-delayed proton decay of {sup 23}Al for nucleosynthesis in novae

Journal Article · Fri Apr 15 00:00:00 EDT 2011 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.83.045808· OSTI ID:21499634

Saastamoinen, A; Aeystoe, J ^[1]; Trache, L; Banu, A; Hardy, J C; Iacob, V E; McCleskey, M; Roeder, B T; Simmons, E; Tabacaru, G; Tribble, R E ^[2]; Bentley, M A ^[3]; Davinson, T; Woods, P J ^[4]

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1. Department of Physics, University of Jyvaeskylae, P.O. Box 35 (YFL), FI-40014 Finland (Finland)
2. Cyclotron Institute, Texas A and M University, College Station, Texas 77843-3366 (United States)
3. Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)
4. School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom)

The {beta}-delayed {gamma} and proton decay of {sup 23}Al has been studied with an alternative detector setup at the focal plane of the momentum achromat recoil separator MARS at Texas A and M University. We could detect protons down to an energy of 200 keV and determine the corresponding branching ratios. Contrary to results of previous {beta}-decay studies, no strong proton intensity from the decay of the isobaric analog state (IAS) of the {sup 23}Al ground state at E{sub x}=7803 keV in {sup 23}Mg was observed. Instead we assign the observed low-energy group E{sub p,c.m.}=206 keV to the decay from a state that is 16 keV below the IAS. We measured both proton and gamma branches from the decay of this state at E{sub x}=7787 keV in {sup 23}Mg, which is a very rare case in the literature. Combining our data with its measured lifetime, we determine its resonance strength to be {omega}{gamma}=1.4{sub -0.4}{sup +0.5} meV. The value is in agreement with older direct measurements, but disagrees with a recent direct measurement. This state is the most important resonance for the radiative proton capture {sup 22}Na(p,{gamma}){sup 23}Mg in some astrophysical environments, such as novae.

• OSTI ID: 21499634
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 83, Issue 4; Other Information: DOI: 10.1103/PhysRevC.83.045808; (c) 2011 American Institute of Physics; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALUMINIUM 23
ASTROPHYSICS
BETA DECAY
BRANCHING RATIO
CAPTURE
DELAYED PROTONS
GAMMA DECAY
GROUND STATES
ISOBARIC ANALOGS
KEV RANGE 100-1000
LIFETIME
MAGNESIUM 23
MEV RANGE
NOVAE
NUCLEOSYNTHESIS
PROTON REACTIONS
RECOILS
RESONANCE
SIMULATION
SODIUM 22 TARGET
ALKALINE EARTH ISOTOPES
ALUMINIUM ISOTOPES
BARYON REACTIONS
BARYONS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BINARY STARS
CHARGED-PARTICLE REACTIONS
DECAY
DIMENSIONLESS NUMBERS
ELEMENTARY PARTICLES
ENERGY LEVELS
ENERGY RANGE
ERUPTIVE VARIABLE STARS
EVEN-ODD NUCLEI
FERMIONS
HADRON REACTIONS
HADRONS
ISOTOPES
KEV RANGE
LIGHT NUCLEI
MAGNESIUM ISOTOPES
MILLISECONDS LIVING RADIOISOTOPES
NUCLEAR DECAY
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
NUCLEONS
ODD-EVEN NUCLEI
PHYSICS
PROTONS
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
STARS
SYNTHESIS
TARGETS
VARIABLE STARS