相关论文: Suppression of Excited-State Contributions to Stel…
It is shown that a Coulomb suppression of the stellar enhancement factor occurs in many endothermic reactions at and far from stability. Contrary to common assumptions, reaction measurements for astrophysics with minimal impact of stellar…
It is commonly assumed that reaction measurements for astrophysics should be preferably performed in the direction of positive Q value to minimize the impact of the stellar enhancement factor, i.e. the difference between the laboratory rate…
Fundamental differences in the prediction of reaction rates with intermediate and heavy target nuclei compared to the ones with light nuclei are discussed, with special emphasis on stellar modifications of the rates. Ground and excited…
Nucleosynthesis processes involve reactions on several thousand nuclei, both close to and far off stability. The preparation of reaction rates to be used in astrophysical investigations requires experimental and theoretical input. In this…
Multi-electron screening effects encountered in laboratory astrophysical reactions are investigated by considering the reactants Thomas-Fermi atoms. By means of that model, previous studies are extended to derive the corresponding screening…
We report a significant improvement of an approximate method of including electron Coulomb distortion in electron induced reactions at momentum transfers greater than the inverse of the size of the target nucleus. In particular, we have…
The reaction rates of the key stellar reaction of $^{14}$O($\alpha$,p)$^{17}$F have been reexamined. The previous conclusion, the 6.15-MeV state ($J^{\pi}$=1$^-$) dominating this reaction rate, has been overthrown by a careful reanalysis of…
The reaction rates of the key stellar reaction of $^{14}$O($\alpha$,p)$^{17}$F have been reevaluated. It is thought that the previous 1$^-$ assignment for the 6.15-MeV state is incorrect by a careful reanalysis of the previous experimental…
The contribution of rescattering to final state interactions in the (e,e'p) cross section is studied using a semiclassical model. This approach considers a two-step process with the propagation of an intermediate nucleon and uses Glauber…
Modern models of s-process nucleosynthesis in stars require stellar reaction rates with high precision. Most of the neutron capture cross sections in the s-process have been measured and for an increasing number of reactions the required…
The steep power-law dependence of element abundance enhancements on the mass-to-charge ratios [A/Q] of the ions in impulsive solar energetic-particle (SEP) events causes these enhancements to reflect the temperature-dependent pattern of Q…
We reexamine the weak interaction nuclei having largest contribution to the lepton to baryon fraction Ye by coupling the stellar weak rates and mass abundances for post silicon burning conditions during the presupernova evolution of massive…
The enhancement factor of the resonant thermonuclear reaction rates is calculated for the extremely dense stellar plasmas in the liquid phase. In order to calculate the enhancement factor we use the screening potential which is deduced from…
We calculated the contribution of Coulomb energy to the spacing between the ground and first excited state of $^{229}$Th nucleus as a function of the deformation parameter $\delta$. We show that despite the fact that the odd particle is a…
Purpose: We have investigated the cross section around the lowest direct coincident gamma-particle measurements, where previously only limits could be established with the aim of obtaining a detailed description of the excitation function.…
We propose an "extended Schmidt law" with explicit dependence of the star formation efficiency (SFE=SFR/Mgas) on the stellar mass surface density. This relation has a power-law index of 0.48+-0.04 and an 1-sigma observed scatter on the SFE…
The Gamow-Teller strength distribution from ${}^{88}$Sr was extracted from a $(t,{}^{3}\text{He}+\gamma)$ experiment at 115 MeV/$u$ to constrain estimates for the electron-capture rates on nuclei around $N=50$, between and including…
In dense stars the nuclear reaction rates are influenced by screening effects arising from both ions and electrons. In this paper we calculate the enhancement factors due to electron polarization in the high-density, degenerate and…
The energy density functional (EDF) method is very widely used in nuclear physics, and among the various existing functionals those based on the relativistic Hartree (RH) approximation are very popular because the exchange contributions…
In nuclear physics, it is well known that the electromagnetic (Coulomb) interaction between final state products can drastically effect particle reaction rates. Near thresholds, for example, nuclear alpha decay is suppressed while nuclear…