相关论文: Low-Energy Direct Capture in the 16O(alpha,gamma)2…
The astrophysical reaction rates of the 16O(a,g)20Ne capture reaction and its inverse 20Ne(g,a)16O photodisintegration reaction are given by the sum of several narrow resonances and a small direct capture contribution at low temperatures.…
The radiative capture cross sections of $^{12}$C($\alpha$,$\gamma$)$^{16}$O and derived reaction rates are calculated from the direct capture potential model. The resulting $S$-factor at low energies is found to be dominated by $E$2…
During the slow neutron capture process in massive stars, reactions on light elements can both produce and absorb neutrons thereby influencing the final heavy element abundances. At low metallicities, the high neutron capture rate of 16-O…
The $\mathrm{^{20}Ne(p, \gamma)^{21}Na}$ reaction is the slowest in the NeNa cycle and directly affects the abundances of the Ne and Na isotopes in a variety of astrophysical sites. Here we report the measurement of its direct capture…
The cross sections of the 8Li(n,gamma)9Li and 8B(p,gamma)9C capture reactions have been analyzed using the direct capture model. At low energies which is the astrophysically relevant region the capture process is dominated by E1 transitions…
The reaction $^{17}$O$(p,\gamma)^{18}$F influences hydrogen-burning nucleosynthesis in several stellar sites, such as red giants, asymptotic giant branch (AGB) stars, massive stars and classical novae. In the relevant temperature range for…
The cross section of the $^{9}$Be(n,$\gamma$)$^{10}$Be reaction was calculated in the direct capture model. All parameters of the calculations were adjusted to properties of the $^{9}$Be + n system at thermal energies. The calculated cross…
$^{13}$N($p,\gamma$)$^{14}$O is one of the key reactions in the hot CNO cycle which occurs at stellar temperatures around $T_9$ $\geq$ 0.1. Up to now, some uncertainties still exist for the direct capture component in this reaction, thus an…
The astrophysical S-factor of the 4He-12C radiative capture is calculated in the potential model at the energy range 0.1-2.0 MeV. Radiative capture 12C(\alpha,\gamma)16O is extremely relevant for the fate of massive stars and determines if…
The 15N(p,g)16O reaction represents a break out reaction linking the first and second cycle of the CNO cycles redistributing the carbon and nitrogen abundances into the oxygen range. The reaction is dominated by two broad resonances at Ep =…
A potential model is applied for the analysis of the astrophysical direct nuclear capture process $^{16}$O(p,$\gamma)^{17}$F. The phase-equivalent potentials of the Woods-Saxon form for the p$-^{16}$O interaction are examined which…
The photodisintegration of $^{16}$O is predicted to be dominated by $E$2 excitation in the vicinity of the $\alpha$-particle threshold. The reaction rates of $^{12}$C($\alpha$,$\gamma$)$^{16}$O are expected to be determined from this…
We investigate the low-temperature reaction rates for radiative capture processes of three particles. We compare direct and sequential capture mechanisms and rates using realistic phenomenological parametrizations of the corresponding…
The $^{22}$Ne($p,\gamma$)$^{23}$Na reaction, part of the neon-sodium cycle of hydrogen burning, may explain the observed anticorrelation between sodium and oxygen abundances in globular cluster stars. Its rate is controlled by a number of…
We investigate the energy dependence of the astrophysical S factors for the reactions 7Be(p,gamma)8B, the primary source of high-energy solar neutrinos in the solar pp chain, and 16O(p,gamma)17F, an important reaction in the CNO cycle. Both…
We have evaluated the electron capture rates on $^{20}$Ne, $^{20}$F, $^{24}$Mg, $^{24}$Na and the $\beta$ decay rates for $^{20}$F and $^{24}$Na at temperature and density conditions relevant for the late-evolution stages of stars with…
The $^{14}\textrm{N(p,}\gamma\textrm{)}^{15}\textrm{O}$ reaction is the slowest reaction of the carbon-nitrogen cycle of hydrogen burning and thus determines its rate. The precise knowledge of its rate is required to correctly model…
A semi-microscopic model for the low-energy photodisintegration of the 9Be nucleus is constructed, and the experimental data are analyzed with its help. The older radioactive isotope data are supported by this analysis. The theoretical…
The reaction 13C(alpha,n) is considered to be the main source of neutrons for the s-process in AGB stars. At low energies the cross section is dominated by the 1/2+ 6.356 MeV sub-threshold resonance in 17O whose contribution is determined…
The astrophysical $S$ factor and reaction rates of the direct capture process $^{6}$Li(p,$\gamma)^{7}$Be are estimated within a two-body single-channel potential model approach. Central potentials of the Gaussian-form in the $^2P_{3/2}$ and…