par Palacios, Ana 
;Arnould, Marcel ;Meynet, Georges
Référence Astronomy & astrophysics, 443, 1, page (243-250)
Publication Publié, 2005-11
;Arnould, Marcel ;Meynet, Georges Référence Astronomy & astrophysics, 443, 1, page (243-250)
Publication Publié, 2005-11
Article révisé par les pairs
| Résumé : | New models of rotating and non-rotating stars are computed for initial masses between 25 and 120 M⊙ and for metallicities Z = 0.004, 0.008, 0.020, and 0.040 with the aim of reexamining the wind contribution of Wolf-Rayet (WR) stars to the 19F enrichment of the interstellar medium. Models with an initial rotation velocity vi = 300 km s -1 are found to globally eject less 19F than the non-rotating models. We compare our new predictions with those of Meynet & Arnould (2000, A&A, 355, 176), and demonstrate that the 19F yields are very sensitive to the still uncertain 19F(α, p) 22Ne rate and to the adopted mass loss rates. Using the recommended mass loss rate values that take into account the clumping of the WR wind and the NACRE reaction rates, when available, we obtain WR 19F yields that are significantly lower than predicted by Meynet & Arnould (2000, A&A, 355, 176) and that would make WR stars non-important contributors to the galactic 19F budget. In view, however, of the large nuclear and mass loss rate uncertainties, we consider that the question of the WR contribution to the galactic 19F remains quite open. © ESO 2005. |
