Bibcode
Luridiana, V.; Peimbert, A.; Peimbert, M.
Bibliographical reference
The Eight Texas-Mexico Conference on Astrophysics (Eds. M. Reyes-Ruiz & E. Vázquez-Semadeni) Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias) Vol. 18, pp. 56-59 (2003) (http://www.astroscu.unam.mx/~rmaa/)
Advertised on:
9
2003
Citations
0
Refereed citations
0
Description
We discuss the effects of collisional enhancement of Balmer lines on the
determination of the primordial helium abundance. To this aim, we
present a photoionization model of the metal-poor extragalactic H 0
region SBS 0335-052. We show that the derived helium abundance (Y) of
this H 0 region depends on the amount of collisional excitation
affecting the Balmer lines, both directly (through an underestimation of
the actual He/H ratio) and indirectly (through an overestimation of the
interstellar reddening). We detail how each of these effects affects the
derived value of Y.