The s - process weak component : uncertainties due to convective overshooting
نویسنده
چکیده
Using a new s-nucleosynthesis code coupled with the stellar evolution code Star2003, simulations have been performed to study the impact of the convection treatment on the s-process during core He-burning of a 25 M⊙ star (ZAMS mass) with an initial metallicity of Z=0.02. Particular attention has been devoted to the impact of the extent of overshooting on the s-process efficiency. The results show enhancements of about a factor 2-3 in s-process efficiency (measured as the average overproduction factor of the 6 s-only nuclear species with 60 . A . 90) with overshooting parameter values in the range 0.01-0.035, compared to results obtained with the same model but without overshooting. The impact of these results on the p-process model based on type II supernovae is discussed.
منابع مشابه
The s - process weak component : uncertainties due to convection theory
Using a new s-nucleosynthesis code coupled with the stellar evolution code Star2003, simulations have been performed to study the impact of convection treatment on the s-process during core He-burning of a 25 M⊙ star (ZAMS mass) with initial solar metallicity. A diffusive approach, with the diffusion constant proportional to the convective velocity obtained from the mixing length theory, has be...
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