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arXiv · 2009.11633

The CHEOPS mission

Willy Benz·Christopher Broeg·Andrea Fortier·Nicola Rando·Thomas Beck·Mathias Beck·Didier Queloz·David Ehrenreich·Pierre Maxted·Kate Isaak·Nicolas Billot·Yann Alibert·Roi Alonso·Carlos António·Joel Asquier·Timothy Bandy·Tamas Bárczy·David Barrado·Susana Barros·Wolfgang Baumjohann·Anja Bekkelien·Maria Bergomi·Federico Biondi·Xavier Bonfils·Luca Borsato·Alexis Brandeker·Martin-Diego Busch·Juan Cabrera·Virginie Cessa·Sébastien Charnoz·Bruno Chazelas·Andrew Collier Cameron·Carlos Corral Van Damme·David Cortes·Melvyn Davies·Magali Deleuil·Adrien Deline·Laetitia Delrez·Olivier Demangeon·Brice-Olivier Demory·Anders Erikson·Jacopo Farinato·Luca Fossati·Malcolm Fridlund·David Futyan·Davide Gandolfi·Antonio Garcia Munoz·Michaël Gillon·Pascal Guterman·Antonio Gutierrez·Johann Hasiba·Kevin Heng·Eduardo Hernandez·Sergio Hoyer·Laszlo Kiss·Zsolt Kovacs·Thibault Kuntzer·Jacques Laskar·Alain Lecavelier des Etangs·Monika Lendl·Amador López·Ivan Lora·Christophe Lovis·Theresa Lüftinger·Demetrio Magrin·Luca Malvasio·Luca Marafatto·Harald Michaelis·Diana de Miguel·David Modrego·Matteo Munari·Valerio Nascimbeni·Göran Olofsson·Harald Ottacher·Roland Ottensamer·Isabella Pagano·Roberto Palacios·Enric Pallé·Gisbert Peter·Daniele Piazza·Giampaolo Piotto·Alberto Pizarro·Don Pollaco·Roberto Ragazzoni·Francesco Ratti·Heike Rauer·Ignasi Ribas·Martin Rieder·Reiner Rohlfs·Frederic Safa·Mario Salatti·Nuno Santos·Gaetano Scandariato·Damien Ségransan·Attila Simon·Alexis Smith·Michael Sordet·Sergio Sousa·Manfred Steller·Gyula Szabó
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Abstract

The CHaracterising ExOPlanet Satellite (CHEOPS) was selected in 2012, as the first small mission in the ESA Science Programme and successfully launched in December 2019. CHEOPS is a partnership between ESA and Switzerland with important contributions by ten additional ESA Member States. CHEOPS is the first mission dedicated to search for transits of exoplanets using ultrahigh precision photometry on bright stars already known to host planets. As a follow-up mission, CHEOPS is mainly dedicated to improving, whenever possible, existing radii measurements or provide first accurate measurements for a subset of those planets for which the mass has already been estimated from ground-based spectroscopic surveys and to following phase curves. CHEOPS will provide prime targets for future spectroscopic atmospheric characterisation. Requirements on the photometric precision and stability have been derived for stars with magnitudes ranging from 6 to 12 in the V band. In particular, CHEOPS shall be able to detect Earth-size planets transiting G5 dwarf stars in the magnitude range between 6 and 9 by achieving a photometric precision of 20 ppm in 6 hours of integration. For K stars in the magnitude range between 9 and 12, CHEOPS shall be able to detect transiting Neptune-size planets achieving a photometric precision of 85 ppm in 3 hours of integration. This is achieved by using a single, frame-transfer, back-illuminated CCD detector at the focal plane assembly of a 33.5 cm diameter telescope. The 280 kg spacecraft has a pointing accuracy of about 1 arcsec rms and orbits on a sun-synchronous dusk-dawn orbit at 700 km altitude. The nominal mission lifetime is 3.5 years. During this period, 20% of the observing time is available to the community through a yearly call and a discretionary time programme managed by ESA.

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Willy Benz, Christopher Broeg, Andrea Fortier, Nicola Rando, Thomas Beck, Mathias Beck, Didier Queloz, David Ehrenreich, Pierre Maxted, Kate Isaak, Nicolas Billot, Yann Alibert, Roi Alonso, Carlos António, Joel Asquier, Timothy Bandy, Tamas Bárczy, David Barrado, Susana Barros, Wolfgang Baumjohann, Anja Bekkelien, Maria Bergomi, Federico Biondi, Xavier Bonfils, Luca Borsato, Alexis Brandeker, Martin-Diego Busch, Juan Cabrera, Virginie Cessa, Sébastien Charnoz, Bruno Chazelas, Andrew Collier Cameron, Carlos Corral Van Damme, David Cortes, Melvyn Davies, Magali Deleuil, Adrien Deline, Laetitia Delrez, Olivier Demangeon, Brice-Olivier Demory, Anders Erikson, Jacopo Farinato, Luca Fossati, Malcolm Fridlund, David Futyan, Davide Gandolfi, Antonio Garcia Munoz, Michaël Gillon, Pascal Guterman, Antonio Gutierrez, Johann Hasiba, Kevin Heng, Eduardo Hernandez, Sergio Hoyer, Laszlo Kiss, Zsolt Kovacs, Thibault Kuntzer, Jacques Laskar, Alain Lecavelier des Etangs, Monika Lendl, Amador López, Ivan Lora, Christophe Lovis, Theresa Lüftinger, Demetrio Magrin, Luca Malvasio, Luca Marafatto, Harald Michaelis, Diana de Miguel, David Modrego, Matteo Munari, Valerio Nascimbeni, Göran Olofsson, Harald Ottacher, Roland Ottensamer, Isabella Pagano, Roberto Palacios, Enric Pallé, Gisbert Peter, Daniele Piazza, Giampaolo Piotto, Alberto Pizarro, Don Pollaco, Roberto Ragazzoni, Francesco Ratti, Heike Rauer, Ignasi Ribas, Martin Rieder, Reiner Rohlfs, Frederic Safa, Mario Salatti, Nuno Santos, Gaetano Scandariato, Damien Ségransan, Attila Simon, Alexis Smith, Michael Sordet, Sergio Sousa, Manfred Steller, Gyula Szabó. 2020-09-24. The CHEOPS mission. https://doi.org/10.1007/s10686-020-09679-4

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