Using CHEOPS to confirm small transiting exoplanets orbiting bright stars

Exoplanets which transit their host stars are unique in allowing detailed characterisation of planetary radius, mass and atmospheric properties. NASA's TESS mission, which has so far observed 97% of the sky with precise photometry, is especially adept at detecting small transiting planets orbiting the brightest & closest stars. It is these for which the most precise bulk characterisation, for example of the planetary masses via the radial velocity (RV) technique, and atmospheric characterisation via transmission spectroscopy with JWST observations. However, the limited precision and noncontinuous observing strategy of TESS means it is unable to find the smallest or longest period planets. ESA’s CHEOPS mission is a 30cm space telescope launched to near earth orbit in 2019 and capable of precise photometry of bright stars. I will present multiple avenues whereby we have used CHEOPS observations to confirm new transiting exoplanets. This includes confirming low-amplitude TESS candidate planets in the HIP 29442 system, serendipitous detection of additional planets in the nu2 Lupi, HD 108236 & LHS 1903 systems, and RV-assisted transit detections in the TOI-561 system. The most productive approach has been to target candidates showing two non-continuous TESS transits. This has lead to around 20 newly detected sub-Neptunes on long periods, including in multi-planet systems such as TOI-2076, HIP 9618, and the resonant 6-planet system HD110067.

Fecha: 
31/10/2024 - 12:30
Conferenciante: 
Dr. Hugh Osborn
Filiación: 
Physics Institute, University of Bern & Institute for Particle & Astrophysics, ETH Zurich


Seminarios