Revised Primordial Helium Abundance Based on New Atomic Data
We have derived a primordial helium abundance of Yp=0.2477+/-0.0029, based on new atomic physics computations of the recombination coefficients of He I and of the collisional excitation of the H I Balmer lines together with observations and photoionization models of metal-poor extragalactic H II regions. The new atomic data increase our previous
Peimbert, Manuel et al.
Fecha de publicación:
9
2007