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Centro de Astrofísica da Universidade do Porto

Asteroseismic estimate of helium abundance of 16 Cyg A,B

K. Verma, J. P. S. Faria, H. M. Antia, S. Basu, A. Mazumdar, M. J. P. F. G. Monteiro, T. Appourchaux, W. J. Chaplin, R. A. García, T. S. Metcalfe

Abstract
The helium ionization zone in a star leaves a characteristic signature on its oscillation frequencies, which can be used to estimate the helium content in the envelope of the star. We use the oscillation frequencies of 16 Cyg A and B, obtained using 2.5 years of Kepler data, to estimate the envelope helium abundance of these stars. We find the envelope helium abundance to lie in the range 0.231–0.251 for 16 Cyg A and 0.218–0.266 for 16 Cyg B.

The Space Photometry Revolution
(Eds.) R.A. García, J. Ballot

EPJ Web of Conferences
Vol. 101, Page 06066
2015

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