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Your search keyword '"Maisonneuve, F."' showing total 5 results
Start Over Author "Maisonneuve, F." Topic pulsating stars
5 results on '"Maisonneuve, F."'

1. Results from Classification Observations and a Multi-site Campaign on γ Doradus and SPB Type Stars.

Author

Wright, D. J., De Cat, P., Pollard, K. R., Maisonneuve, F., Kilmartin, P. M., Telting, J. H., Kambe, E., Poretti, E., Lehmann, H., Yang, S., Mkrtichian, D., Laney, D., and Fu, J. N.

Subjects
STAR observations, VARIABLE stars, PULSATING stars, STELLAR oscillations, ASTRONOMICAL spectroscopy
Abstract

As part of a observational project aiming to investigate the effects of rotation on main-sequence g-mode non-radial pulsation we have obtained at least one (generally more) high-resolution spectroscopic observation of more than 50 confirmed or candidate γ Doradus and slowly pulsating B stars and have completed a spectroscopic multi-site campaign. The campaign was one of those outlined in De Cat et al. (these proceedings) and included five observatories and focused on the γ Doradus, and now planet hosting star HD 218396 (HR 8799) and the SPB stars HD 21071 and HD 25558. [ABSTRACT FROM AUTHOR]

Published
2009
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2. Frequency analysis and pulsational mode identification of two γ Doradus stars: HD 40745 and HD 189631.

Author

Maisonneuve, F., Pollard, K. R., Cottrell, P. L., Wright, D. J., De Cat, P., Mantegazza, L., Kilmartin, P. M., Suárez, J. C., Rainer, M., and Poretti, E.

Subjects
*PULSATING stars, *ASTEROSEISMOLOGY, *COMPUTER software, *STELLAR spectra, *FREQUENCIES of oscillating systems, *RADIAL velocity of stars, *ASTROPHYSICS
Abstract

ABSTRACT 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. [ABSTRACT FROM AUTHOR]

Published
2011
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3. Spectroscopic Mode-Identification of γ Doradus Stars.

Author

Maisonneuve, F., Pollard, K. R., Cottrell, P. L., Kilmartin, P. M., Wright, D. J., and De Cat, P.

Subjects
*ASTRONOMICAL spectroscopy, *PULSATING stars, *STELLAR collisions, *TELESCOPES, *STAR observations
Abstract

We are undertaking an extensive observational campaign of a number of non-radially pulsating stars using the high-resolution HERCULES spectrograph on the 1.0-m telescope at the Mt John University Observatory (MJUO). This paper outlines our campaign and presents preliminary results for one γ Doradus star, HD40745, as an example. About 250 spectra of HD40745 have been obtained. We have used Wright’s (2008) representative cross-correlation line-profile technique to extract line profiles and these have then been analysed using the FAMIAS package (Zima 2008) to derive a spectroscopic mode identification. [ABSTRACT FROM AUTHOR]

Published
2009
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4. Towards asteroseismology of main-sequence g-mode pulsators: spectroscopic multi-site campaigns for slowly pulsating B stars and γ Doradus stars.

Author

De Cat, P., Wright, D. J., Pollard, K. R., Maisonneuve, F., Kilmartin, P. M., Lehmann, H., Yang, S., Kambe, E., Saesen, S., Carrier, F., Mkrtichian, D., Mantegazza, L., Rainer, M., Poretti, E., Laney, D., and Fu, J. N.

Subjects
ASTEROSEISMOLOGY, PULSATING stars, VARIABLE stars, STELLAR oscillations, STAR observations
Abstract

We introduce the spectroscopic multi-site campaigns that are organised for a sample of slowly pulsating B and γ Doradus stars to make a big step forward in the asteroseismic studies of these main-sequence g-mode pulsators. [ABSTRACT FROM AUTHOR]

Published
2009
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5. Is HD 147787 a double-lined binary with two pulsating components? Preliminary results from a spectroscopic multi-site campaign.

Author

De Cat, P., Wright, D. J., Pollard, K. R., Maisonneuve, F., Kilmartin, P. M., and Laney, D.

Subjects
STELLAR oscillations, ASTRONOMICAL spectroscopy, ASTRONOMICAL photometry, PULSATING stars, STAR observations
Abstract

The double-lined binary HD 147787 has been observed from three southern observatories to gather a time series of high-quality, high-resolution spectroscopic data. We here report upon the first analysis of the 2008 data obtained with the spectrographs HARPS and HERCULES. An eccentric orbit of 39.880(2) days was obtained. For the primary component. we derived a projected rotational velocity νsin i of 7(2) km s-1 and found that the temporal changes of the line profiles are dominated by 0.6897(8) d-1, which is the main frequency known from photometry. There is evidence for multiperiodicity. For the secondary component, we derived a νsin i of 33(2) km s 1, but there is no firm evidence for pulsations. [ABSTRACT FROM AUTHOR]

Published
2009
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