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

CÓRSICO, A. H.; GARCÍA-BERRO, E.; MILLER BERTOLAMI, M. M.; ROMERO, A. D.; ISERN, J.; SULLIVAN, D. J.; ALTHAUS, L. G.; KEPLER, S. O.; CHOTE, P.

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2016 vol. 2016

1475-7516

We employ an asteroseismic model of L19-2, a relatively massive (M ~ 0.75 M⊙) and hot (Teff ~ 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 ~ 113 s and Π ~ 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 ma cos2β  25 meV or an axion-electron coupling constant of gae  7 × 10−13.