Helium content in the solar convective envelope from helioseismology

Using measured frequencies of the solar p-modes we determined the fractional mass content of helium in the Sun's envelope. We found that its value lies between 0.23 and 0.24. This result appears to be unaffected by the uncertainties in the treatment of the atmosphere and the outer convective zone, but it relies in a sensitive way on calculation of thermodynamical quantities. (author)