The reactions {sup 25}Mg({alpha},n){sup 28}Si, {sup 26}Mg({alpha},n){sup 29}Si and their possible impact on nucleosynthesis

Journal Article · Wed Jan 28 04:00:00 EST 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3087033· OSTI ID:21255428

Falahat, S; Couder, M; Goerres, J; Stech, E; Wiescher, M ^[1]; Kratz, K -L; Ott, U ^[2]; O'Brien, S ^[1]; Pignatari, M ^[3]

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1. University of Notre Dame, Department of Physics, Nuclear Science Laboratory, Notre Dame, IN, 46556 (United States)
2. Max-Planck-Institut fuer Chemie, Mainz, 55128 (Germany)
3. Astrophysics Group, Keele University, Keele, Staffordshire ST5 5BG (United Kingdom)

At the time neon burning is activated in massive stars, large amounts of {sup 25}Mg and {sup 26}Mg have been accumulated from the previous evolutionary phases. In particular, at typical temperatures for neon shell burning, the reactions {sup 25}Mg({alpha},n){sup 28}Si and {sup 26}Mg({alpha},n){sup 29}Si become efficient providing additional neutron fluxes and affecting the nucleosynthesis distribution. Good knowledge of the reaction rates is required to study their effect on nucleosynthesis during neon shell burning conditions (T{sub 9} > or approx. 1.5, where T{sub 9} is the temperature in gigakelvin). At the Nuclear Science Laboratory, University of Notre Dame, IN, USA we developed a neutron detector to investigate the {sup 25}Mg({alpha},n){sup 28}Si and {sup 26}Mg({alpha},n){sup 29}Si reactions as possible neutron sources during neon shell burning. In the present paper we briefly describe the experimental procedures developed to measure those reactions. Finally, we discuss the impact of {sup 25}Mg({alpha},n){sup 28}Si and {sup 26}Mg({alpha},n){sup 29}Si on the s-process nucleosynthesis for the barium isotopes.

• OSTI ID: 21255428
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1090; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALPHA REACTIONS
BARIUM ISOTOPES
MAGNESIUM 25
MAGNESIUM 25 TARGET
MAGNESIUM 26
MAGNESIUM 26 TARGET
NEON
NEUTRON DETECTION
NEUTRON DETECTORS
NEUTRON FLUX
NEUTRON SOURCES
NEUTRONS
NUCLEOSYNTHESIS
REACTION KINETICS
S PROCESS
SHELL MODELS
SILICON 28
SILICON 29
STARS