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New insights on pulsating white dwarfs from 3D radiation-hydrodynamical simulations

Published online by Cambridge University Press:  27 October 2016

Pier-Emmanuel Tremblay ,
Gilles Fontaine ,
Hans-Günter Ludwig ,
Alexandros Gianninas  and
Mukremin Kilic
Pier-Emmanuel Tremblay
Affiliation:
Department of Physics, University of Warwick, Gibbet Hill Rd., Coventry, CV4 7AL, UK email: P-E.Tremblay@warwick.ac.uk
Gilles Fontaine
Affiliation:
Département de Physique, Université de Montréal, C. P. 6128, Succursale Centre-Ville, Montréal, QC H3C 3J7, Canada
Hans-Günter Ludwig
Affiliation:
Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, D-69117 Heidelberg, Germany
Alexandros Gianninas
Affiliation:
Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK, 73019, USA
Mukremin Kilic
Affiliation:
Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK, 73019, USA
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Abstract

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We have recently computed a grid of 3D radiation-hydrodynamical simulations for the atmosphere of pure-hydrogen DA white dwarfs in the range 5.0 < log g < 9.0. Our grid covers the full ZZ Ceti instability strip where pulsating DA white dwarfs are located. We have significantly improved the theoretical framework to study these objects by removing the free parameters of 1D convection, which were previously a major modeling hurdle. We present improved atmospheric parameter determinations based on spectroscopic fits with 3D model spectra, allowing for an updated definition of the empirical edges of the ZZ Ceti instability strip. Our 3D simulations also precisely predict the depth of the convection zones, narrowing down the internal layers where pulsation are being driven. We hope that these 3D effects will be included in asteroseismic models in the future to predict the region of the HR diagram where white dwarfs are expected to pulsate.

Keywords

White DwarfsConvectionHydrodynamicsAsteroseismology
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 11 , General Assembly A29B: Astronomy in Focus , August 2015 , pp. 667 - 672
Copyright
Copyright © International Astronomical Union 2016 

References

Allard, N. F., Kielkopf, J. F., & Loeillet, B. 2004, A&A, 424, 347 Google Scholar
Althaus, L. G., Córsico, A. H., Isern, J., & García-Berro, E. 2010, A&AR, 18, 471 Google Scholar
Böhm-Vitense, E. 1958, ZAp, 46, 108 Google Scholar
Böhm, K. H. & Cassinelli, J. 1971, A&A, 12, 21 Google Scholar
Caffau, E., Ludwig, H.-G., Steffen, M., Freytag, B., & Bonifacio, P. 2011, Sol. Phys., 268, 255 Google Scholar
Fontaine, G., Brassard, P., Wesemael, F., & Tassoul, M. 1994, ApJ (Letters), 428, L61 Google Scholar
Fontaine, G., Brassard, P., & Bergeron, P. 2001, PASP, 113, 409 CrossRefGoogle Scholar
Fontaine, G. & Brassard, P. 2008, PASP, 120, 1043 Google Scholar
Freytag, B., Steffen, M., Ludwig, H.-G., et al. 2012, Journal of Computational Physics, 231, 919 Google Scholar
Gautschy, A., Ludwig, H.-G., & Freytag, B. 1996, A&A, 311, 493 Google Scholar
Gianninas, A., Bergeron, P., & Ruiz, M. T. 2011, ApJ, 743, 138 Google Scholar
Gianninas, A., Dufour, P., Kilic, M., et al. 2014, ApJ, 794, 35 CrossRefGoogle Scholar
van Grootel, V., Dupret, M.-A., Fontaine, G., et al. 2012, A&A, 539, A87 Google Scholar
Hummer, D. G. & Mihalas, D. 1988, ApJ, 331, 794 Google Scholar
Tremblay, P.-E. & Bergeron, P. 2009, ApJ, 696, 1755 Google Scholar
Tremblay, P.-E., Bergeron, P., & Gianninas, A. 2011, ApJ, 730, 128 CrossRefGoogle Scholar
Tremblay, P.-E., Ludwig, H.-G., Steffen, M., & Freytag, B. 2013, A&A, 559, A104 Google Scholar
Tremblay, P.-E., Ludwig, H.-G., Freytag, B., et al. 2015a, ApJ, 799, 142 CrossRefGoogle Scholar
Tremblay, P.-E., Gianninas, A., Kilic, M., et al. 2015b, ApJ, 809, 148 Google Scholar
Winget, D. E., Hansen, C. J., Liebert, J., et al. 1987, ApJ (Letters), 315, L77 Google Scholar