The solar-like CoRoT target HD 170987: spectroscopic and seismic observations
Savita Mathur
(1, 2)
,
Rafael A. Garcia
(1)
,
Claude Catala
(3)
,
H. Bruntt
(3)
,
Benoît Mosser
(3)
,
Thierry Appourchaux
(4)
,
Jérôme Ballot
(5)
,
Orlagh L. Creevey
(6)
,
Patrick Gaulme
(4)
,
Saskia Hekker
(7)
,
Daniel Huber
(8)
,
Christoffer Karoff
(7)
,
Laurent Piau
(1)
,
Clara Regulo
(6)
,
Ian W. Roxburgh
(9, 3)
,
David Salabert
(6)
,
Graham A. Verner
(9)
,
Michel Auvergne
(3)
,
Annie Baglin
(3)
,
William J. Chaplin
(7)
,
Yvonne P. Elsworth
(7)
,
Eric Michel
(3)
,
Davoud-Reza Samadi
(3)
,
Koichi Sato
(1)
,
Dennis Stello
(8)
1
CEA -
Commissariat à l'énergie atomique et aux énergies alternatives
2 High Altitude Observatory, National Center for Atmospheric Research
3 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
4 IAS - Institut d'astrophysique spatiale
5 LATT - Laboratoire Astrophysique de Toulouse-Tarbes
6 ULL - Universidad de La Laguna [Tenerife - SP]
7 University of Birmingham [Birmingham]
8 SIfA - Sydney Institute for Astronomy
9 School of Mathematical Sciences, Queen Mary Unversity of London
2 High Altitude Observatory, National Center for Atmospheric Research
3 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
4 IAS - Institut d'astrophysique spatiale
5 LATT - Laboratoire Astrophysique de Toulouse-Tarbes
6 ULL - Universidad de La Laguna [Tenerife - SP]
7 University of Birmingham [Birmingham]
8 SIfA - Sydney Institute for Astronomy
9 School of Mathematical Sciences, Queen Mary Unversity of London
Résumé
Context. The CoRoT mission is in its third year of observation and the data from the second long run in the galactic centre direction are being analysed. The solar-like oscillating stars that have been observed up to now have given some interesting results, specially concerning the amplitudes that are lower than predicted. We present here the results from the analysis of the star HD 170987.
Aims: The goal of this research work is to characterise the global parameters of HD 170987. We look for global seismic parameters such as the mean large separation, maximum amplitude of the modes, and surface rotation because the signal-to-noise ratio in the observations does not allow us to measure individual modes. We also aim to retrieve the parameters of the star and its chemical composition.
Methods: We studied the chemical composition of the star through ground-based observations performed with the NARVAL spectrograph. We used several methods to calculate the global parameters from the acoustic oscillations based on CoRoT data. The light curve of the star has been interpolated with inpainting algorithms to reduce the effect of data gaps.
Results: We found the power excess related to p modes in the range [400-1200] muHz with a mean large separation of 55.2 ± 0.8 muHz with a probability above 95
Aims: The goal of this research work is to characterise the global parameters of HD 170987. We look for global seismic parameters such as the mean large separation, maximum amplitude of the modes, and surface rotation because the signal-to-noise ratio in the observations does not allow us to measure individual modes. We also aim to retrieve the parameters of the star and its chemical composition.
Methods: We studied the chemical composition of the star through ground-based observations performed with the NARVAL spectrograph. We used several methods to calculate the global parameters from the acoustic oscillations based on CoRoT data. The light curve of the star has been interpolated with inpainting algorithms to reduce the effect of data gaps.
Results: We found the power excess related to p modes in the range [400-1200] muHz with a mean large separation of 55.2 ± 0.8 muHz with a probability above 95