
TY  - JOUR
A1  - Flynn, Chris 
T1  - Cosmic Helium Production
JF  - Publications of the Astronomical Society of Australia
JO  - Publ. Astron. Soc.  Aust.
Y1  - 2004
VL  - 21
IS  - 2
SP  - 126
EP  - 128
KW  - Galaxy: abundances &#8212; Galaxy: evolution
UR  - https://doi.org/10.1071/AS04015 
N2  - K-dwarfs are very long lived, slowly evolving stars, so that their present day helium Y and metal content (metallicity Z) is essentially the same as when they were born. K-dwarfs thus contain a fossil record of the amount of helium and metals which has been produced in successive stellar generations over the lifetime of the Galaxy. We here estimate the amount of helium compared to the amount of metals produced via stellar fusion (&#916; Y/&#916;Z). We use K-dwarfs in the Hipparcos catalogue for which accurate metallicities and luminosities are available. By including recently measured K-dwarfs with super-solar metallicities we are able to obtain a very significant improvement on previous studies. The best fitting value is &#916;Y/&#916;Z = 2.4 &#177; 0.4 at the 68% confidence level. Values as low as 1 or as high as 4 are excluded with more than 99&percnt; confidence. 
ER  -

