Interpreting the line-profile variations of subdwarf B pulsators: The case of PG1336-018 (NY Virginis)

Vuckovic M, Ostensen RH, Aerts C, Telting JH, Heber U, Oreiro R (2009)

Publication Type: Journal article

Publication year: 2009

Journal

Astronomy & Astrophysics EDP Sciences

Book Volume: 505

Pages Range: 239-248

Journal Issue: 1

DOI: 10.1051/0004-6361/200912457

Abstract

Aims. We analyze the high-resolution time-resolved VLT/uves spectra of PG1336-018, a rapidly pulsating subdwarf B (sdB) primary in a close orbit with an M5 companion, with the aim to detect the pulsational signal of the primary in line-profile variations.Methods. After removing the dominant radial-velocity component inherent to the orbital motion and taking only out-of-eclipse data we computed cross-correlation functions (CCFs) for each individual spectrum and assumed these to approximate the average line profile. We computed predictions of line-profile variations for pulsating sdB stars and present their diagnostic value for mode identification.Results. We detect the pulsation mode at 5435 μ Hz in the line-profile variations of the CCFs which allows us to characterize the detected pulsation mode of PG1336-018.Conclusions. We model the pulsational perturbations of synthetic spectra for a star with physical parameters like PG1336-018?and confront them with the observed spectra. We find that low order Balmer lines can be used as diagnostic tool to identify pulsation modes. A detailed line-profile analysis of the perturbed time-series spectra excludes the l = |m| = (3,3), (1,0), (2,1) and (2,0) modes, but does not allow a unique mode identification among the radial or sectoral dipole or quadrupole modes. © 2009 ESO.

Authors with CRIS profile

Ulrich Heber Naturwissenschaftliche Fakultät

Involved external institutions

Katholieke Universiteit Leuven (KUL) / Catholic University of Leuven

Belgium (BE) Nordic Optical Telescope

Spain (ES)

How to cite

APA:

Vuckovic, M., Ostensen, R.H., Aerts, C., Telting, J.H., Heber, U., & Oreiro, R. (2009). Interpreting the line-profile variations of subdwarf B pulsators: The case of PG1336-018 (NY Virginis). Astronomy & Astrophysics, 505(1), 239-248. https://doi.org/10.1051/0004-6361/200912457

MLA:

Vuckovic, Maja, et al. "Interpreting the line-profile variations of subdwarf B pulsators: The case of PG1336-018 (NY Virginis)." Astronomy & Astrophysics 505.1 (2009): 239-248.

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