The primordial helium abundance and the number of neutrino families

Bibcode
2016RMxAA..52..419P
Luridiana, V.; Peimbert, M.; Peimbert, A.
Bibliographical reference

Revista Mexicana de Astronomía y Astrofísica Vol. 52, pp. 419--424 (2016)

Advertised on:
10
2016
Number of authors
3
IAC number of authors
1
Citations
87
Refereed citations
70
Description
Based on observations of HII regions and on the new computations of the recombination coefficients of the HeI lines by Porter el al. we obtain a primordial helium abundance by mass of Y_P = 0.2446 ± 0.0029. We consider thirteen sources of error for the Y_P determination; some of them are mainly due to systematic effects, while the rest are mainly due to statistical effects. We compare our results with other determinations of Y_P present in the literature. Combining our Y_P value with computations of primordial nucleosynthesis we find a number of neutrino species {N_{eff}=2.90± 0.22}, and a neutron mean life τ_{ν}=872± 14s.
Type
Refereed
Early universe
Galaxies
H II regions

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