Decay Spectroscopy for Nuclear Astrophysics: {beta}-delayed Proton Decay

Journal Article · Wed Nov 30 00:00:00 EST 2011 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3664152· OSTI ID:22003891

Trache, L; Simmons, E; Spiridon, A; McCleskey, M; Roeder, B T; Tribble, R E ^[1]; Saastamoinen, A; Jokinen, A; Aysto, J ^[2]; Davinson, T; Woods, P J ^[3]; Pollacco, E; Kebbiri, M ^[4]; Pascovici, G ^[5]

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1. Texas A and M University, College Station, TX 77845 (United States)
2. University of Jyvaskyla, Jyvaskyla (Finland)
3. University of Edinburgh, Edinburgh (United Kingdom)
4. CEA/IRFU Saclay (France)
5. IKP, Universitaet zu Koeln (Germany)

Decay spectroscopy is one of the oldest indirect methods in nuclear astrophysics. We have developed at TAMU techniques to measure beta- and beta-delayed proton decay of sd-shell, proton-rich nuclei. The short-lived radioactive species are produced in-flight, separated, then slowed down (from about 40 MeV/u) and implanted in the middle of very thin Si detectors. These allowed us to measure protons with energies as low as 200 keV from nuclei with lifetimes of 100 ms or less. At the same time we measure gamma-rays up to 8 MeV with high resolution HPGe detectors. We have studied the decay of {sup 23}Al, {sup 27}P, {sup 31}Cl, all important for understanding explosive H-burning in novae. The technique has shown a remarkable selectivity to beta-delayed charged-particle emission and works even at radioactive beam rates of a few pps. The states populated are resonances for the radiative proton capture reactions {sup 22}Na(p,{gamma}){sup 23}Mg(crucial for the depletion of {sup 22}Na in novae), {sup 26m}Al(p,{gamma}){sup 27}Si and {sup 30}P(p,{gamma}){sup 31}S(bottleneck in novae and XRB burning), respectively. More recently we have radically improved the technique using a gas based detector we call AstroBox.

• OSTI ID: 22003891
• Journal Information: AIP Conference Proceedings, Vol. 1409, Issue 1; Conference: 4. international conference on proton emitting nuclei and related topics, Bordeaux (France), 6-10 Jun 2011; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALUMINIUM 23
ASTROPHYSICS
BETA DECAY
CAPTURE
CHLORINE 31
DELAYED PROTONS
HIGH-PURITY GE DETECTORS
KEV RANGE
LIFETIME
MAGNESIUM 23
NOVAE
NUCLEOSYNTHESIS
PHOSPHORUS 27
PHOSPHORUS 30
PROTON-EMISSION DECAY
SHELL MODELS
SILICON 27
SODIUM 22