TY - JOUR
T1 - Estimating the p-mode frequencies of the solar twin 18 Scorpii
AU - Bazot, M.
AU - Campante, T. L.
AU - Chaplin, W. J.
AU - Carfantan, H.
AU - Bedding, T. R.
AU - Dumusque, X.
AU - Broomhall, A. M.
AU - Petit, P.
AU - Théado, S.
AU - Van Grootel, V.
AU - Arentoft, T.
AU - Castro, M.
AU - Christensen-Dalsgaard, J.
AU - Do Nascimento, J. D.
AU - Dintrans, B.
AU - Kjeldsen, H.
AU - Monteiro, M. J.P.F.G.
AU - Santos, N. C.
AU - Sousa, S.
AU - Vauclair, S.
N1 - Funding Information:
The authors would like to thank the referee for his very careful report and careful comments. We feel that he helped to improve significantly this paper. This work was co-supported by grants SFRH/BPD/ 47994/2008, SFRH/BD/36240/2007 and PTDC/CTE-AST/098754/2008 from FCT/MCTES and FEDER, Portugal. M.B. thanks O. Benomar for very interesting and fruitful discussions. A.-M.B. and W.J.C. acknowledge the support of the UK Science and Technology Facilities Council (STFC). Funding for the Stellar Astrophysics Centre is provided by The Danish National Research Foundation. The research is supported by the ASTERISK project (ASTERoseismic Investigations with SONG and Kepler) funded by the European Research Council (Grant agreement No.: 267864).
PY - 2012
Y1 - 2012
N2 - Solar twins have been a focus of attention for more than a decade, because their structure is extremely close to that of the Sun. Today, thanks to high-precision spectrometers, it is possible to use asteroseismology to probe their interiors. Our goal is to use time series obtained from the HARPS spectrometer to extract the oscillation frequencies of 18 Sco, the brightest solar twin. We used the tools of spectral analysis to estimate these quantities. We estimate 52 frequencies using an MCMC algorithm. After examination of their probability densities and comparison with results from direct MAP optimization, we obtain a minimal set of 21 reliable modes. The identification of each pulsation mode is straightforwardly accomplished by comparing to the well-established solar pulsation modes. We also derived some basic seismic indicators using these values. These results offer a good basis to start a detailed seismic analysis of 18 Sco using stellar models.
AB - Solar twins have been a focus of attention for more than a decade, because their structure is extremely close to that of the Sun. Today, thanks to high-precision spectrometers, it is possible to use asteroseismology to probe their interiors. Our goal is to use time series obtained from the HARPS spectrometer to extract the oscillation frequencies of 18 Sco, the brightest solar twin. We used the tools of spectral analysis to estimate these quantities. We estimate 52 frequencies using an MCMC algorithm. After examination of their probability densities and comparison with results from direct MAP optimization, we obtain a minimal set of 21 reliable modes. The identification of each pulsation mode is straightforwardly accomplished by comparing to the well-established solar pulsation modes. We also derived some basic seismic indicators using these values. These results offer a good basis to start a detailed seismic analysis of 18 Sco using stellar models.
KW - Methods: data analysis
KW - Stars: individual: 18 Sco
KW - Stars: oscillations
KW - Techniques: radial velocities
UR - http://www.scopus.com/inward/record.url?scp=84864984746&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84864984746&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/201117963
DO - 10.1051/0004-6361/201117963
M3 - Article
AN - SCOPUS:84864984746
SN - 0004-6361
VL - 544
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
M1 - A106
ER -