Asteroseismic potential of CHEOPS

¹ School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
e-mail: A.Moya@bham.ac.uk
² Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
³ Dept. Física Teórica y del Cosmos, Universidad de Granada, Campus de Fuentenueva s/n, 10871 Granada, Spain
⁴ Depto. Astrofísica, Centro de Astrobiología (INTA-CSIC), ESAC campus, Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Spain
⁵ Space sciences, Technologies and Astrophysics Research (STAR) Institute, Université de Liège, Allée du Six Août 19C, 4000 Liège, Belgium

Received: 4 July 2018
Accepted: 1 November 2018

Abstract

Context. Asteroseismology has been impressively boosted during the last decade mainly thanks to space missions such as Kepler/K2 and CoRoT. This has a large impact, in particular, in exoplanetary sciences since the accurate characterization of the exoplanets is convoluted in most cases with the characterization of their hosting star. In the decade before the expected launch of the ESA mission PLATO 2.0, only two important missions will provide short-cadence high-precision photometric time-series: NASA–TESS and ESA–CHEOPS missions, both having high capabilities for exoplanetary sciences.

Aims. In this work we want to explore the asteroseismic potential of CHEOPS time-series.

Methods. Following the works estimating the asteroseismic potential of Kepler and TESS, we have analysed the probability of detecting solar-like pulsations using CHEOPS light-curves. Since CHEOPS will collect runs with observational times from hours up to a few days, we have analysed the accuracy and precision we can obtain for the estimation of ν_max. This is the only asteroseismic observable we can recover using CHEOPS observations. Finally, we have analysed the impact of knowing ν_max in the characterization of exoplanet host stars.

Results. Using CHEOPS light-curves with the expected observational times we can determine ν_max for massive G and F-type stars from late main sequence (MS) on, and for F, G, and K-type stars from post-main sequence on with an uncertainty lower than a 5%. For magnitudes V <  12 and observational times from eight hours up to two days, the HR zone of potential detectability changes. The determination of ν_max leads to an internal age uncertainty reduction in the characterization of exoplanet host stars from 52% to 38%; mass uncertainty reduction from 2.1% to 1.8%; radius uncertainty reduction from 1.8% to 1.6%; density uncertainty reduction from 5.6% to 4.7%, in our best scenarios.