The s-process that occurs in the shell carbon-burning phase of a typical massive star of 25 solar masses is examined. It is shown that neutron captures during shell C-burning can significantly change the s-abundances. The composition of the s-processed material ejected by a 25 solar mass model is evaluated, and the contributions of massive stars to the chemical enrichment of the Galaxy in s-isotopes are estimated. The s-contributions to the solar composition from low-mass stars are then taken into account, and possibility of matching the solar distribution of the s-isotopes produced by the weak component is investigated. It is found that the s-process in massive stars can completely account for the weak component observed in the solar system and can put important constraints on the scenario of the chemical evolution of the Galaxy.
S-process nucleosynthesis in massive stars and the weak component. II - Carbon burning and galactic enrichment
BUSSO, Maurizio Maria;
1991
Abstract
The s-process that occurs in the shell carbon-burning phase of a typical massive star of 25 solar masses is examined. It is shown that neutron captures during shell C-burning can significantly change the s-abundances. The composition of the s-processed material ejected by a 25 solar mass model is evaluated, and the contributions of massive stars to the chemical enrichment of the Galaxy in s-isotopes are estimated. The s-contributions to the solar composition from low-mass stars are then taken into account, and possibility of matching the solar distribution of the s-isotopes produced by the weak component is investigated. It is found that the s-process in massive stars can completely account for the weak component observed in the solar system and can put important constraints on the scenario of the chemical evolution of the Galaxy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
