[en] Context: .One of the main goals of the COROT mission is to get precise photometric observations of selected bright stars in order to allow the modelling of their interior through asteroseismology. However, in order to interpret the asteroseismological data, the effective temperature, surface gravity, and chemical composition of the stars must be known with sufficient accuracy.Aims.To carry out this task, we have developed a spectroscopic method called APASS (Atmospheric Parameters and Abundances from Synthetic Spectra) which allows precise analysis of stars with a moderate to high rotational velocity, which is the case for most primary COROT targets.Methods.Our method is based on synthetic spectra in which individual lines are replaced by analysis units (isolated lines or line blends, depending on the crowding of the spectral region and on the rotational broadening). It works differentially with respect to the Sun and allows the atmospheric parameters and chemical abundances to be determined by considering analysis units with different sensitivities to these various parameters.Results.Using high signal-to-noise spectra and the APASS method, we determined the atmospheric parameters and chemical abundances of 13 primary COROT targets. Our results agree well with those obtained by Bruntt using his software VWA and with those obtained with the software TEMPLOGG. However, in both cases, our error bars are significantly smaller than those of other methods. Our effective temperatures are also in excellent agreement with those obtained with the IR photometry method. For five stars with relatively low rotational velocity, we also performed an analysis with a classical equivalent-width method to test agreement with APASS results. We show that equivalent-width measurements by Gaussian or Voigt profile-fitting are sensitive to the rotational broadening, leading to systematic errors whenever the projected rotation velocity is non-negligible. The APASS method appears superior in all cases and should thus be preferred.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Gillon, Michaël ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique et traitement de l'image
Magain, Pierre ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique et traitement de l'image
Language :
English
Title :
High precision determination of the atmospheric parameters and abundances of the COROT main targets
scite shows how a scientific paper has been cited by providing the context of the citation, a classification describing whether it supports, mentions, or contrasts the cited claim, and a label indicating in which section the citation was made.
Bibliography
Anstee, S. D., & O'Mara, B. J. 1995, MNRAS, 276, 859
Anstee, S. D., O'Mara, B. J., & Ross, J. E. 1997, MNRAS, 284, 202
Baglin, A., et al. 1998, Asteroseismology from space - The COROT experiment, In New eyes to see inside the Sun and stars, IAU, 185, 301
Baglin, A., Deleuil, M., Michel, E., & Catala, C. 2004, Preliminary list of candidate targets, COROT.LESIA.04.47
Baranne, A., Queloz, D., Mayor, M., et al. 1996, A&AS, 119, 373
Barklem, P. S., & O'Mara, B. J. 2000, MNRAS, 311, 535
Bruntt, H., Catala, C., Garrido, R., et al. 2002, A&A, 389, 345
Bruntt, H., Bikmaev, I. F., Catala, C., et al. 2004, A&A, 425, 683
Butler, R. P., Vogt, S. S., Marcy, G. W., et al. 2000, ApJ, 545, 504
Canuto, V. M., Goldman, I., & Mazitelli, I. 1996, ApJ, 473, 550
Delbouille, L., Roland, G., & Neven, L. 1973, Atlas photometrique du spectre solaire, Université de Liège, Institut d'Astrophysique
Grevesse, N., & Sauval, A. J. 1998, Space Sci. Rev., 85, 161
Kupka, F., Piskunov, N. E., Ryabchikova, T. A., Stempels, H. C., & Weiss, W. W. 1999, A&AS, 138, 119
Kurucz, R. L. 1993, CD-ROM 18, ATLAS9 Stellar Atmosphere Pgrograms and 2 km s-1 Grid
Kurucz, R. L. 1998, http://kurucz.harvard.edu
Mayor, M., Pepe, F., Queloz, D., et al. 2003, ESO messenger, 114, 20
Nendwich, J., Nesvacil, N., Heiter, U., & Kupka, F. 2003, Modelling of Stellar Atmospheres, ed. N. E. Piskunov, W. W. Weiss, & D. F. Gray, IAU Symp., 210
Nendwich, J., Heiter, U., Kupka, F., & Nesvacil, N. 2004, ed. W. W. Weiss, CoAst, 144, 43
Piskunov, N. E., Kupka, F., Ryabchikova, T. A., Weiss, W. W., & Jeffery, C. S. 1995, A&AS, 112, 525
Queloz, D., Mayor, M., Weber, L., et al. 2000, A&A, 354, 99
Ribas, I., Solano, E., Masana, E., & Giménez, A. 2003, A&A, 411, 501
Rouan, et al. 2000, Detecting Earth-Uranus class planets with the space mission COROT. In Darwin and Astronomy - The Infrared Space Interferometer, ESA SP-451, 221
Rogers, N. Y. 1995, Comm. in Asteroseismology, 78
Ryabchikova, T. A., Piskunov, N. E., Stempels, H. C., Kupka, F., & Weiss, W. W. 1999, Proc. of the 6th International Colloquium on Atomic Spectra and Oscillator Strengths, Victoria BC, Canada, Physica Scripta, T83, 162
Santos, N. C., Israelian, G., & Mayor, M. 2004, A&A, 415, 1153
Soderblom, D. 1982, ApJ, 263, 239
Solano, E., Catala, C., Garrido, R., et al. 2005, AJ, 129, 1, 547
Similar publications
Sorry the service is unavailable at the moment. Please try again later.
This website uses cookies to improve user experience. Read more
Save & Close
Accept all
Decline all
Show detailsHide details
Cookie declaration
About cookies
Strictly necessary
Performance
Strictly necessary cookies allow core website functionality such as user login and account management. The website cannot be used properly without strictly necessary cookies.
This cookie is used by Cookie-Script.com service to remember visitor cookie consent preferences. It is necessary for Cookie-Script.com cookie banner to work properly.
Performance cookies are used to see how visitors use the website, eg. analytics cookies. Those cookies cannot be used to directly identify a certain visitor.
Used to store the attribution information, the referrer initially used to visit the website
Cookies are small text files that are placed on your computer by websites that you visit. Websites use cookies to help users navigate efficiently and perform certain functions. Cookies that are required for the website to operate properly are allowed to be set without your permission. All other cookies need to be approved before they can be set in the browser.
You can change your consent to cookie usage at any time on our Privacy Policy page.