Differential asteroseismic study of seismic twins observed by CoRoT⋆
Comparison of HD 175272 with HD 181420
Institut d’Astrophysique et de Géophysique de l’Université de
Liège, Allée du 6 Août
2 Department of Astronomy and Space Science, Erciyes University, 38039 Melikgazi, Kayseri, Turkey
3 LESIA, CNRS, Université Pierre et Marie Curie, Université Denis Diderot, Observatoire de Paris, 92195 Meudon Cedex, France
4 Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
5 Université de Toulouse, UPS-OMP, IRAP, 31400 Toulouse, France
6 Laboratoire AIM, CEA/DSM, CNRS – Université Paris Diderot, IRFU/SAp, 91191 Gif-sur-Yvette Cedex, France
7 Institut d’Astrophysique Spatiale, UMR 8617, Université Paris Sud, 91405 Orsay Cedex, France
8 Space Science Institute, 4750 Walnut street Suite# 205, Boulder, CO 80301, USA
9 Instituto de Astrofisica de Canarias, 38205, La Laguna, Tenerife, Spain
10 Université de Nice-Sophia Antipolis, CNRS UMR 7293, Observatoire de la Côte d’Azur, Laboratoire J.L. Lagrange, BP 4229, 06304 Nice Cedex 04, France
11 Universidad de La Laguna, Dpto de Astrofisica, 38206, La Laguna, Tenerife, Spain
12 NRS, IRAP, 14 avenue Édouard Belin, 31400 Toulouse, France
Accepted: 2 September 2013
Context. The CoRoT short asteroseismic runs give us the opportunity to observe a large variety of late-type stars through their solar-like oscillations. We report the observation and modeling of the F5V star HD 175272.
Aims. Our aim is to define a method for extracting as much information as possible from a noisy oscillation spectrum.
Methods. We followed a differential approach that consists of using a well-known star as a reference to characterize another star. We used classical tools such as the envelope autocorrelation function to derive the global seismic parameters of the star. We compared HD 175272 with HD 181420 through a linear approach, because they appear to be asteroseismic twins.
Results. The comparison with the reference star enables us to substantially enhance the scientific output for HD 175272. First, we determined its global characteristics through a detailed seismic analysis of HD 181420. Second, with our differential approach, we measured the difference of mass, radius and age between HD 175272 and HD 181420.
Conclusions. We have developed a general method able to derive asteroseismic constraints on a star even in case of low-quality data. This method can be applied to stars with interesting properties but low signal-to-noise ratio oscillation spectrum, such as stars hosting an exoplanet or members of a binary system.
Key words: asteroseismology / stars: interiors / techniques: photometric / stars: evolution / stars: individual: HD 175272 / stars: individual: HD 181420
© ESO, 2013