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arXiv · 1605.06458

An asteroseismic constraint on the mass of the axion from the period drift of the pulsating DA white dwarf star L19-2

Alejandro H. Córsico·Alejandra D. Romero·Leandro G. Althaus·Enrique García-Berro·Jordi Isern·S. O. Kepler·Marcelo M. Miller Bertolami·Denis J. Sullivan·Paul Chote
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Abstract

We employ an asteroseismic model of L19-2, a relatively massive ($M_{\star} \sim 0.75 M_{\sun}$) and hot ($T_{\rm eff} \sim 12\,100$ K) pulsating DA (H-rich atmosphere) white dwarf star (DAV or ZZ Ceti variable), and use the observed values of the temporal rates of period change of its dominant pulsation modes ($Π\sim 113$ s and $Π\sim 192$ s), to derive a new constraint on the mass of the axion, the hypothetical non-barionic particle considered as a possible component of the dark matter of the Universe. If the asteroseismic model employed is an accurate representation of L19-2, then our results indicate hints of extra cooling in this star, compatible with emission of axions of mass $m_{\rm a} \cos^2 β\lesssim 25$ meV or an axion-electron coupling constant of $g_{\rm ae} \lesssim 7 \times 10^{-13}$.

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Alejandro H. Córsico, Alejandra D. Romero, Leandro G. Althaus, Enrique García-Berro, Jordi Isern, S. O. Kepler, Marcelo M. Miller Bertolami, Denis J. Sullivan, Paul Chote. 2016-07-12. An asteroseismic constraint on the mass of the axion from the period drift of the pulsating DA white dwarf star L19-2. https://doi.org/10.1088/1475-7516%2F2016%2F07%2F036

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