Title of programme: Improving the bulk densities for small planets observed with HARPS-N, K2, TESS, and CHEOPS
Abstract: Transiting planets offer a unique opportunity to measure the bulk density of an exoplanet. This enables studies of planet interior composition and in turn informs planet formation and evolution so we can get a better understanding of the large diversity of exoplanets in the Universe. Despite thousands of known exoplanets, there is still a lack of well characterised small planets. The HARPS-N Science Team has been leading the effort of characterising these small transiting planets, representing a third of these well-characterised small planets. In this proposal we are requesting two CHEOPS transits for each of twelve HARPS-N targets. These targets are planet candidates from the K2 or TESS mission, and a large chunk of the HARPS-N GTO observing time has been or is being invested in order to measure precise and accurate masses for these planets. Securing CHEOPS transits will serve the double goal of improving the radii and masses of these planets. The precise transit photometry of CHEOPS will allow us improve the radius. Furthermore, obtaining two new transits with CHEOPS will reduce the uncertainties on the period and transit time allowing narrower priors on the RV model and thus enabling a more precise mass measurement. Therefore, by combining precise CHEOPS and HARPS-N data, and archival K2/TESS photometry we will be able to deliver the best possible bulk density measurement for these small planets.
Temporal Coverage
2021-05-06T00:11:54Z / 2021-05-06T13:46:00Z
Version
3.0
Mission Description
CHEOPS (Benz et al., https://doi.org/10.1007/s10686-020-09679-4) is a European Space Agency (ESA) mission in partnership with Switzerland with important contributions to the payload and the ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden and the United Kingdom.
The satellite has a single payload comprising an ultra-high precision photometer covering the 330 - 1100 nm wavelength range in a single photometric band. Observations are made as part of the Guaranteed Time Observing Programme that is formulated by the CHEOPS Science Team, and the Guest Observers Programme through which the Community at large can apply for CHEOPS time.