On the accuracy of helioseismic determination of solar helium abundance
نویسندگان
چکیده
The Helium abundance in the solar envelope is one of the most important seismic observables. We investigate the accuracy of its determination taking into account uncertainties in the data and in the inversion procedure. Our best value for the helium abundance in the photosphere is Y = 0.248. The estimated uncertainty of 0.002 is dominated by uncertainties in the inversion. This does not account for possibly larger inaccuracies in the thermodynamical data.
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