A new method for the spectroscopic identification of stellar non-radial pulsation modes II. Mode identification of the d Scuti star FG Virginis
- Autor(en)
- Wolfgang Zima, D Wright, J Bentley, Peter L. Cottrell, Ulrike Heiter, P Mathias, Ennio Poretti, Holger Lehmann, T J Montemayor, Michel Breger
- Abstrakt
Aims. We present a mode identification based on new high-resolution time-series spectra of the non-radially pulsating d Scuti star FG Vir (HD 106384, V = 6.57, A5V). From 2002 February to June a global Delta Scuti Network (DSN) campaign, utilizing high-resolution spectroscopy and simultaneous photometry has been conducted for FG Vir in order to provide a theoretical pulsation model. In this campaign we have acquired 969 Echelle spectra covering 147 h at six observatories. Methods. The mode identification was carried out by analyzing line profile variations by means of the Fourier parameter fit method, where the observational Fourier parameters across the line are fitted with theoretical values. This method is especially well suited for determining the azimuthal order m of non-radial pulsation modes and thus complementary with the method of Daszynska-Daszkiewicz (2002) which does best at identifying the degree l. Results. 15 frequencies between 9.2 and 33.5 d-1 were detected spectroscopically. We determined the azimuthal order m of 12 modes and constrained their harmonic degree l. Only modes of low degree (l = 4) were detected, most of them having axisymmetric character mainly due to the relatively low projected rotational velocity of FG Vir. The detected non-axisymmetric modes have azimuthal orders between -2 and 1. We derived an inclination of 19°, which implies an equatorial rotational rate of 66 km s-1. Œ ESO 2006.
- Organisation(en)
- Institut für Astrophysik
- Externe Organisation(en)
- University of Canterbury, Université Côte d'Azur, INAF Osservatorio Astronomico di Brera, Thüringer Landessternwarte Tautenburg, University of Texas, Austin, Uppsala University
- Journal
- Astronomy & Astrophysics
- Band
- 455
- Seiten
- 235-246
- Anzahl der Seiten
- 12
- ISSN
- 0004-6361
- DOI
- https://doi.org/10.1051/0004-6361:20064877
- Publikationsdatum
- 2006
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/ddd35731-f390-4a40-b95c-44a701cfb15b