Observations of the pulsating subdwarf B star Feige 48: Constraints on evolution and companions

M. D. Reed (1) , Steven D. Kawaler (2) , S. Zola (3) , X. J. Jiang (4) , Stefan Dreizler (5) , S. L. Schuh (5) , J. L. Deetjen (5) , R. Kalytis (6) , E. G. Meistas (6) , R. Janulis (7) , D. Alisauskas (6) , J. Krzesinski (8) , Maja Vuckovic (2) , P. A. Moskalik (9) , W. Ogloza (8) , A. Baran (8) , G. Stachowski (3) , Donald W. Kurtz (10) , J. M. Gonzalez Perez (11) , A. Mukadam (12) , T. K. Watson (13) , C. Koen (12) , P. A. Bradley (14) , M. S. Cunha (15) , M. Kilic (12) , E. W. Klumpe (16) , R. F. Carlton (16) , Gerald Handler (17) , D. M. Kilkenny (17) , R. Riddle (2) , N. Dolez (18) , Gérard Vauclair (18) , Michel Chevreton (19, 20, 21) , M. A. Wood (22) , A. Grauer (23) , G. Bromage (10) , J.-E. Solheim (11) , R. Østensen (24) , A. Ulla (25) , M. Burleigh (26) , S. Good (26) , Ö. Hürkal (27) , R. Anderson (28) , E. Pakstiene (7)

1 Department of Physics, Astronomy, and Materials Science, Missouri State University
2 Department of Physics and Astronomy, Iowa State University
3 Astronomical Observatory, Jagiellonia University
4 National Astronomical Observatoires-CAS
5 Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen
6 Institute of Material Science and Applied Research of Vilnius University, Astronomical Observatory
7 Institute of Theoretical Physics and Astronomy, Astronomical Observatory
8 Mount Suhora Observatory, Cracow Pedagogical University
9 CAMK - Centrum Astronomiczne im. M. Kopernika, Warszawa
10 Centre for Astrophysics, University of Central Lancashire
11 Institutt for Fysikk, Universitetet i Tromsø
12 Department of Astronomy, University of Texas
13 Southwestern University
14 LANL - Los Alamos National Laboratory
15 Universidade do Porto = University of Porto
16 Department of Physics and Astronomy, Middle Tennessee State University
17 SAAO - South African Astronomical Observatory
18 OMP - Observatoire Midi-Pyrénées
19 DAEC - Departement d'Astrophysique Extragalactique et de Cosmologie
20 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
21 Pôle Astronomie du LESIA
22 Department of Physics and Space Sciences and SARA Observatory, Florida Institute of Technology, Melbourne
23 Department of Physics and Astronomy, University of Arkansas
24 Isaac Newton Group of Telescopes
25 Universidade de Vigo
26 Department of Physics and Astronomy, University of Leicester
27 Department of Astronomy and Space Sciences, Ege University
28 Department of Physics and Astronomy, University of North Carolina

Since pulsating subdwarf B (sdBV or EC14026) stars were first discovered, observational efforts have tried to realize their potential for constraining the interior physics of extreme horizontal branch stars. Difficulties encountered along the way include uncertain mode identifications and a lack of stable pulsation mode properties. Here we report on Feige 48, an sdBV star for which follow-up observations have been obtained spanning more than four years. These observations show some stable pulsation modes.

Domaines: Astrophysique [astro-ph]

M. D. Reed, Steven D. Kawaler, S. Zola, X. J. Jiang, Stefan Dreizler, et al.. Observations of the pulsating subdwarf B star Feige 48: Constraints on evolution and companions. Monthly Notices of the Royal Astronomical Society, 2004, 348, pp.1164-1174. ⟨10.1111/j.1365-2966.2004.07438.x⟩. ⟨hal-03785810⟩