Non-radial pulsations in the <i>γ</i> Doradus star HD 195068

Jankov, S.; Mathias, P.; Chapellier, E.; Contel, J. M. Le; Sareyan, J. P.

doi:10.1051/0004-6361:20053117

Cited by 6 publications

(7 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A candidate for a fourth frequency occurs near 0.28 or its alias at 1.28 d −1 , between f 1 and f 2 . The first frequency found by Jankov et al (2006) in spectroscopic data (1.61 d −1 ) is not significantly present in any of the photometric data sets.…”

Section: Hd 195068 = Hip 100859 = Hr 7828 = V2121 Cygmentioning

confidence: 70%

Long-term photometric monitoring with the Mercator telescope

Cuypers¹,

Aerts

Cat³

et al. 2009

A&A

View full text Add to dashboard Cite

Context. γ Dor stars are excellent targets for asteroseismology since the gravity modes present in these stars probe the deep stellar interiors. Mode identification will improve the knowledge of these stars considerably. Aims. A selected group of γ Dor stars and some candidates were observed with the Mercator telescope to find and/or confirm the periodicities in the light variations and to derive reliable amplitude ratios in different pass bands. Methods. A frequency analysis was performed on all new data obtained in the Geneva photometric system. In order to have more reliable and accurate frequencies, the new data were combined with similar data from the literature and with Hipparcos observations. A set of frequencies that minimized the residuals in a harmonic fit was searched for while allowing means and amplitudes to vary from one observation set to another. Results. Frequencies and amplitudes in the photometric passbands of the Geneva system are given for 21 γ Dor stars. We report the discovery of HD 74504 as a newly found γ Dor star. Conclusions. Our study provides the first extensive multicolour database for the understanding of gravity modes in F-type stars.

show abstract

Section: Hd 195068 = Hip 100859 = Hr 7828 = V2121 Cygmentioning

confidence: 70%

Long-term photometric monitoring with the Mercator telescope

Cuypers¹,

Aerts

Cat³

et al. 2009

A&A

View full text Add to dashboard Cite

show abstract

“…Previously, attempts to identify the modes of pulsations in γ Doradus stars have been made, some used only photometry (Breger et al 1997; Zerbi et al 1997, 1999; Rodríguez et al 2006b), others used spectroscopy and worked with the moment method (Balona et al 1996; Aerts & Krisciunas 1996; Aerts & Kaye 2001; Aerts et al 2004) or the intensity‐period search (IPS) method based on Doppler imaging (Hatzes 1998; Handler et al 2002b; Jankov et al 2006) or even both methods (Uytterhoeven et al 2008). Wright (2008) performed the only two previous mode identifications on γ Doradus stars using the FPF method, on QW Puppis (HD 55892) and HD 139095.…”

Section: Discussionmentioning

confidence: 99%

Frequency analysis and pulsational mode identification of two γ Doradus stars: HD 40745 and HD 189631★

Maisonneuve

Pollard

Cottrell

et al. 2011

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. Mode identification will improve the knowledge of these stars considerably and allow an understanding of the issues with current pulsational models. A frequency analysis followed by a mode identification were done based on the high‐resolution spectroscopic data of two γ Doradus stars: HD 189631 and HD 40745. Extensive spectroscopic data sets are obtained by three instruments: HARPS, FEROS and HERCULES. We obtained 422 spectra for HD 189631 and 248 spectra for HD 40745. The pulsational frequencies were determined by four methods: analysis of the variation in equivalent width, variation in radial velocity, asymmetry of the line profile and the pixel‐by‐pixel frequency analysis. The mode identification was done using the recently developed Fourier Parameter Fit method. Without achieving the same degree of confidence for all results, we report the identification of four pulsational modes in HD 189631: (ℓ= 1; m =+1) at f1= 1.67 d−1; (3; −2) at f2= 1.42 d−1; (2; −2) at f3= 0.07 d−1; and (4; +1) at f4= 1.82 d−1; and two modes in HD 40745: (2; −1) at f1= 0.75 d−1 and (3; −3) at f2= 1.09 d−1. This study provides the first pulsational analysis based on spectroscopy of HD 189631 and HD 40745. We discuss the performance of current methods of analysis and outline the difficulties presented by γ Doradus stars.

show abstract

“…• Gamma Doradus stars, whose mere existence was a highlight of Ap 99 (Sect. 5.5) indeed have gas flowing along the surface of the star (Jankov et al 2006). The mechanism (to be shared with the Maia stars if they exist, pulsating Be's, and maybe the slowly pulsating B stars) may be a new class of pulsational instability-retrograde mixed modes, a hybrid between Rossby waves and Poincare modes (Townsend 2005).…”

Section: Pulsating Starsmentioning

confidence: 99%

Astrophysics in 2006

2007

View full text Add to dashboard Cite

The fastest pulsar and the slowest nova; the oldest galaxies and the youngest stars; the weirdest life forms and the commonest dwarfs; the highest energy particles and the lowest energy photons. These were some of the extremes of Astrophysics 2006. We attempt also to bring you updates on things of which there is currently only one (habitable planets, the Sun, and the universe) and others of which there are always many, like meteors and molecules, black holes and binaries.Comment: 244 pages, no figure

show abstract

Non-radial pulsations in the γ Doradus star HD 195068

Cited by 6 publications

References 29 publications

Long-term photometric monitoring with the Mercator telescope

Long-term photometric monitoring with the Mercator telescope

Frequency analysis and pulsational mode identification of two γ Doradus stars: HD 40745 and HD 189631★

Astrophysics in 2006

Contact Info

Product

Resources

About