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Copyright of Congreso Internacional de Investigacion Academia Journals is the property of PDHTech, LLC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Congreso Internacional de Investigacion Academia Journals is the property of PDHTech, LLC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The carbon fusion reaction is crucial in stellar evolution. Despite six decades of studies, there is still a large uncertainty in the reaction rate which limits our understanding of various stellar objects, such as massive stars, type Ia supernovae, and superbursts. In this paper, we review the experimental and theoretical studies of the carbon fusion reaction at sub-barrier energies. An outlook for future studies is also presented. [ABSTRACT FROM AUTHOR]

Abstract. Heavy ion fusion reactions play important roles in a wide variety of stellar burning scenarios. 12C+12C, 12C+16O and 16O+16O are the principle reactions during the advance burning stages of massive star. 12C+12C also triggers the happening of superburst and Type Ia supernovae. The heavy ion fusion reactions of the neutron-rich isotopes such as 24O are the major heating source in the crust of neutron star. In this talk, I will review the challenges and the recent progress in the study of these heavy ion fusion reactions at stellar energies. The outlook for the studies of the astrophysical heavy-ion fusion reactions will also be presented. [ABSTRACT FROM AUTHOR]

Copyright of CISTI (Iberian Conference on Information Systems & Technologies / Conferência Ibérica de Sistemas e Tecnologias de Informação) Proceedings is the property of Conferencia Iberica de Sistemas Tecnologia de Informacao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The 12C+12C reaction is one of the single most important nuclear reactions in astrophysics. It strongly influences late evolution of massive stars as well as the dynamics of type Ia supernovae and x-ray superbursts. An accurate estimation of the cross section at relevant astrophysical energies is extremely important for modeling these systems. However, the situation is complicated by the unpredictable resonance structure observed at higher energies. Two recent studies at Notre Dame have produced results which help reduce the uncertainty associated with this reaction. The first uses correlations with the isotope fusion systems, 12C+13C and 13C+13C, to establish an upper limit on the resonance strengths in 12C+12C. The other focuses on the specific channel 12C+12C→23Mg+n and its low-energy measurement and extrapolation which is relevant to s-process nucleosynthesis. The results from each provide important constraints for astrophysical models. [ABSTRACT FROM AUTHOR]

The 12C+12C fusion reaction is investigated in a multichannel folding model, using the density-dependent DDM3Y nucleon-nucleon interaction. The 12C(01+, 2+, 02+, 3-) states are included, and their densities are taken from a microscopic cluster calculation. Absorption to fusion channels is simulated by a short-range imaginary potential and the model does not contain any fitting parameter. We compute elastic and fusion cross sections simultaneously. The role of 12C+12C inelastic channels and, in particular, of the 12C(01+)+12C(02+ ) channel involving the Hoyle state is important even at low energies. [ABSTRACT FROM AUTHOR]

The carbon fusion project at Notre Dame is aimed towards measuring the 12C+12C fusion cross section and its decay branches relevant to astrophysics down to the lowest possible energies. To complement this approach, we are also exploring new techniques for providing more reliable extrapolations of the cross sections in the energy ranges where experimental data are unavailable. In this paper, we report two recent results: 1) an upper limit for the 12C+12C fusion cross section, and 2) a new measurement of 12C(12C,n) along with an improved extrapolation technique based on the mirror reaction channel, 12C(12C,p). The outlook for astrophysical heavy-ion fusion studies at Notre Dame is also discussed. [ABSTRACT FROM AUTHOR]

The set of fusion reactions 12C+12C play a critical role in several astrophysical processes. In a recent experiment, the fusion reactions 12C+12C have been studied at ECM = 2.10 to 4.75 MeV by γ-ray spectroscopy using a C target of ultra-low hydrogen contamination. The deduced astrophysical S(E) factor exhibits previously unknown resonances at E<=3.0 MeV, in particular a strong and narrow resonance at E = 2.14 MeV, the high-energy tail of the Gamow peak. Current extrapolations of the reaction rate, which assume that the astrophysical S(E) factor varies smoothly with energy within the Gamow window, are thus subject to significant uncertainty. [ABSTRACT FROM AUTHOR]

A parameterization of the spectroscopic factor is presented which almost matches the ones obtained via the microscopic SU(3) model of the nucleus. A short introduction of the algebraic model (the Semimicroscopic Algebraic Cluster Model, SACM) is given. The parameterization of the spectroscopic factor is explained, justified and compared, for light nuclei, to the microscopic SU(3) model. The applications concern the calculation of the total fusion cross section of 12C+12C. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A parameterization of spectroscopic factors is presented that matches perfectly the ones obtained via the microscopic SU(3) model of the nucleus. The model used is the Semimicroscopic Algebraic Cluster Model (SACM) which inlcudes the Pauli-exclusion principle. The parameterization of the spectroscopic factors is given and applied to the fusion cross section of 12C+12C. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]