Triple-α Reaction Research Articles

Fast-neutron spectrometry using the triple-α reaction in the CR-39 detector

The “sensitivity” of CR-39 has been measured for the registration of triple-α tracks in particular, and all charged particle tracks in general, resulting from the interaction of fast neutrons (of energies ranging from ∼ 12 MeV to 19 MeV) with the nuclear constituents of the plastic. The triple-α events result from the reaction 12 C (n,n') 3α, with a Q value of - 7.265 MeV. These sensitivities (i.e. efficiencies in terms of events or tracks per incident neutron) have been measured as functions of the etching time and neutron energy, and also for both the front and the back surface of the detector. The triple-α production efficiency passes through a broad maximum with increasing etching time. The measured efficiency broadly follows the shape of the energy-dependent cross section curve σ(E) for the triple-α reaction.

Unconventional C-12 production in population III stars

view Abstract Citations (12) References (13) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Unconventional C-12 production in population III stars Mitalas, R. Abstract The production of 12C by unconventional nuclear reactions is investigated. The reactions of α-particles with minor constituents of the p-p chain, 7Be and 8B, establish equilibrium abundances of 11B and 11C. For ρ = 10 g cm-3 and (X, Z) = (0.739, 0) the carbon-producing reactions 11B(p, γ)12C and 11C(p, γ)12N(e+ν)12C dominate the triple-α reaction for T6 < 76; the nonresonant triple-α reaction dominates the triple-α reaction for T6 < 61. The relative importance of these reactions in massive Population III stars is discussed. Publication: The Astrophysical Journal Pub Date: March 1985 DOI: 10.1086/162981 Bibcode: 1985ApJ...290..273M Keywords: Carbon Stars; Computational Astrophysics; Main Sequence Stars; Nuclear Fusion; Abundance; Hertzsprung-Russell Diagram; Reaction Kinetics; Temperature Dependence; Astrophysics full text sources ADS |