Whole earth telescope observations of the pulsating subdwarf B Star PG 0014+067

Author(s): M Vuckovic, Steven D. Kawaler, Simon J. O'Toole, Z Csubry, A Baran, S Zola, Pawel A. Moskalik, Eric W. Klumpe, Reed L. Riddle, M. Sean O'Brien, F Mullally, Matt A. Wood, V Wilkat, A Zhou, Mike D. Reed, Donald M. Terndrup, Denis J. Sullivan, S -L Kim, W P Chen, C -W Chen, W -S Hsiao, K Sanchawala, H -T Lee, Xianjun J. Jiang, R Janulis, M Siwak, W Ogloza, Margit Paparó, Zs Bognar, A Sodor, Gerald Handler, Denise Lorenz, Bruno Steininger, R Silvotti, G Vauclair, R Oreiro, Roy H. Ostensen, A Bronowska, B G Castanheira, S O Kepler, L Fraga, Harry L. Shipman, D Childers
Abstract: PG 0014+067 is one of the most promising pulsating subdwarf B stars for seismic analysis, as it has a rich pulsation spectrum. The richness of its pulsations, however, poses a fundamental challenge to understanding the pulsations of these stars, as the mode density is too complex to be explained only with radial and nonradial low-degree (l <3) p-modes without rotational splittings. One proposed solution, suggested by Brassard et al. in 2001 for the case of PG 0014+067 in particular, assigns some modes with high degree (l - 3). On the other hand, theoretical models of sdB stars suggest that they may retain rapidly rotating cores, and so the high mode density may result from the presence of a few rotationally split triplet (l = 1) and quintuplet (l = 2) modes, along with radial (l = 0)p-modes. To examine alternative theoretical models for these stars, we need better frequency resolution and denser longitude coverage. Therefore, we observed this star with the Whole Earth Telescope for two weeks in 2004 October. In this paper we report the results of Whole Earth Telescope observations of the pulsating subdwarf B star PG 0014+067. We find that the frequencies seen in PG 0014+067 do not appear to fit any theoretical model currently available; however, we find a simple empirical relation that is able to match all of the well-determined frequencies in this star. Œ 2006. The American Astronomical Society. All rights reserved.
Organisation(s): Department of Astrophysics
External organisation(s): Katholieke Universiteit Leuven, Iowa State University, Hungarian Academy of Sciences, Pedagogical University of Cracow, Polish Academy of Sciences (PAS), University of Texas, Austin, Yale University, Florida Institute of Technology, Chinese Academy of Sciences (CAS), Case Western Reserve University, Ohio State University, Victoria University of Wellington, Korea Astronomy and Space Science Institute, National Central University, Vilnius University (VU), Jagiellonian University in Krakow, COROT Additional Program Working Group, Observatoire Midi-Pyrénées, University of La Laguna, Universidade Federal de Santa Catarina, Isaac Newton Group of Telescopes, Universidade Federal do Rio Grande do Sul, University of Delaware, Dr. Karl Remeis-Sternwarte
Journal: The Astrophysical Journal: an international review of astronomy and astronomical physics
Volume: 646
Pages: 1230-1240
No. of pages: 11
ISSN: 0004-637X
DOI: https://doi.org/10.1086/505137
Publication date: 2006
Peer reviewed: Yes
Austrian Fields of Science 2012: 103003 Astronomy
Portal url: https://ucrisportal.univie.ac.at/en/publications/2b16b272-16b8-4669-a932-a0e1c7a11fae

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