Search

Your search keyword '"Van Grootel, V"' showing total 582 results
Start Over Author "Van Grootel, V"
582 results on '"Van Grootel, V"'

151. The HD 93963 A transiting system: A 1.04 d super-Earth and a 3.65 d sub-Neptune discovered by TESS and CHEOPS

Author

Serrano, L. M., Gandolfi, D., Hoyer, S., Brandeker, A., Hooton, M. J., Sousa, S., Murgas, F., Ciardi, D. R., Howell, S. B., Benz, W., Billot, N., Floren, H-G, Bekkelien, A., Bonfanti, A., Krenn, A., Mustill, A. J., Wilson, T. G., Osborn, H., Parviainen, H., Heidari, N., Palle, E., Fridlund, M., Adibekyan, V, Fossati, L., Deleuil, M., Knudstrup, E., Collins, K. A., Lam, K. W. F., Grziwa, S., Salmon, S., Albrecht, S. H., Alibert, Y., Alonso, R., Anglada-Escude, G., Barczy, T., Barrado y Navascues, D., Barros, S. C. C., Baumjohann, W., Beck, M., Beck, T., Bieryla, A., Bonfils, X., Boyd, P. T., Broeg, C., Cabrera, J., Charnoz, S., Chazelas, B., Christiansen, J. L., Cameron, A. Collier, Cortes-Zuleta, P., Csizmadia, Sz, Davies, M. B., Deline, A., Delrez, L., Demangeon, O. D. S., Demory, B-O, Dunlavey, A., Ehrenreich, D., Erikson, A., Fortier, A., Fukui, A., Garai, Z., Gillon, M., Gudel, M., Hebrard, G., Heng, K., Huang, C. X., Isaak, K. G., Jenkins, J. M., Kiss, L. L., Laskar, J., Latham, D. W., des Etangs, A. Lecavelier, Lendl, M., Levine, A. M., Lovis, C., Lund, M. B., Magrin, D., Maxted, P. F. L., Narita, N., Nascimbeni, V, Olofsson, G., Ottensamer, R., Pagano, I, Pessanha, A. C. S., V, Peter, G., Piotto, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Ribas, I, Ricker, G., Rowden, P., Santos, N. C., Scandariato, G., Seager, S., Segransan, D., Simon, A. E., Smith, A. M. S., Steller, M., Szabo, Gy M., Thomas, N., Twicken, J. D., Udry, S., Ulmer, B., Van Grootel, V., Vanderspek, R., Viotto, V., Walton, N., Serrano, L. M., Gandolfi, D., Hoyer, S., Brandeker, A., Hooton, M. J., Sousa, S., Murgas, F., Ciardi, D. R., Howell, S. B., Benz, W., Billot, N., Floren, H-G, Bekkelien, A., Bonfanti, A., Krenn, A., Mustill, A. J., Wilson, T. G., Osborn, H., Parviainen, H., Heidari, N., Palle, E., Fridlund, M., Adibekyan, V, Fossati, L., Deleuil, M., Knudstrup, E., Collins, K. A., Lam, K. W. F., Grziwa, S., Salmon, S., Albrecht, S. H., Alibert, Y., Alonso, R., Anglada-Escude, G., Barczy, T., Barrado y Navascues, D., Barros, S. C. C., Baumjohann, W., Beck, M., Beck, T., Bieryla, A., Bonfils, X., Boyd, P. T., Broeg, C., Cabrera, J., Charnoz, S., Chazelas, B., Christiansen, J. L., Cameron, A. Collier, Cortes-Zuleta, P., Csizmadia, Sz, Davies, M. B., Deline, A., Delrez, L., Demangeon, O. D. S., Demory, B-O, Dunlavey, A., Ehrenreich, D., Erikson, A., Fortier, A., Fukui, A., Garai, Z., Gillon, M., Gudel, M., Hebrard, G., Heng, K., Huang, C. X., Isaak, K. G., Jenkins, J. M., Kiss, L. L., Laskar, J., Latham, D. W., des Etangs, A. Lecavelier, Lendl, M., Levine, A. M., Lovis, C., Lund, M. B., Magrin, D., Maxted, P. F. L., Narita, N., Nascimbeni, V, Olofsson, G., Ottensamer, R., Pagano, I, Pessanha, A. C. S., V, Peter, G., Piotto, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Ribas, I, Ricker, G., Rowden, P., Santos, N. C., Scandariato, G., Seager, S., Segransan, D., Simon, A. E., Smith, A. M. S., Steller, M., Szabo, Gy M., Thomas, N., Twicken, J. D., Udry, S., Ulmer, B., Van Grootel, V., Vanderspek, R., Viotto, V., and Walton, N.

Abstract

We present the discovery of two small planets transiting HD 93963A (TOI-1797), a GOV star (M-* = 1.109 +/- 0.043M(circle dot), R-* = 1.043 +/- 0.009 R-circle dot) in a visual binary system. We combined TESS and CHEOPS space-borne photometry with MuSCAT 2 ground-based photometry, 'Alopeke and PHARO high-resolution imaging, TRES and FIES reconnaissance spectroscopy, and SOPHIE radial velocity measurements. We validated and spectroscopically confirmed the outer transiting planet HD 93963 A c, a sub-Neptune with an orbital period of P-c approximate to 3.65 d that was reported to be a TESS object of interest (TOI) shortly after the release of Sector 22 data. HD 93963 A c has amass of M-c = 19.2 +/- 4.1 M-circle plus and a radius of R-c = 3.228 +/- 0.059 R-circle plus, implying a mean density of rho(c) = 3.1 +/- 0.7 g cm(-3). The inner object, HD 93963 A b, is a validated 1.04 d ultra-short period (USP) transiting super-Earth that we discovered in the TESS light curve and that was not listed as a TOI, owing to the low significance of its signal (TESS signal-to-noise ratio approximate to 6.7, TESS + CHEOPS combined transit depth D-b = 141.5(-8.3)(+8.5) ppm). We intensively monitored the star with CHEOPS by performing nine transit observations to confirm the presence of the inner planet and validate the system. HD 93963 A b is the first small (R-b = 1.35 +/- 0.042 R-circle plus) USP planet discovered and validated by TESS and CHEOPS. Unlike planet c, HD 93963 Ab is not significantly detected in our radial velocities (M-b = 7.8 +/- 3.2 M-circle plus). The two planets are on either side of the radius valley, implying that they could have undergone completely different evolution processes. We also discovered a linear trend in our Doppler measurements, suggesting the possible presence of a long-period outer planet. With a V-band magnitude of 9.2, HD 93963 A is among the brightest stars known to host a USP planet, making it one of the most favourable targets for precise mass mea

Published
2022

152. A CHEOPS-enhanced view of the HD 3167 system

Author

Bourrier, V., Deline, A., Krenn, A., Egger, J. A., Petit, A. C., Malavolta, L., Cretignier, M., Billot, N., Broeg, C., Florén, H.-G., Queloz, D., Alibert, Y., Bonfanti, A., Bonomo, A. S., Delisle, J.-B., Demangeon, O. D. S., Demory, B.-O., Dumusque, X., Ehrenreich, D., Haywood, R. D., Howell, S. B., Lendl, M., Mortier, A., Nigro, G., Salmon, S., Sousa, S. G., Wilson, T. G., Adibekyan, V., Alonso, R., Anglada, G., Bárczy, T., Navascues, D. Barrado y, Barros, S. C. C., Baumjohann, W., Beck, M., Benz, W., Biondi, F., Bonfils, X., Brandeker, A., Cabrera, J., Charnoz, S., Csizmadia, Sz., Cameron, A. Collier, Damasso, M., Davies, M. B., Deleuil, M., Delrez, L., Di Fabrizio, L., Erikson, A., Fortier, A., Fossati, L., Fridlund, M., Gandolfi, D., Gillon, M., Güdel, M., Heng, K., Hoyer, S., Isaak, K. G., Kiss, L. L., Laskar, J., des Etangs, A. Lecavelier, Lorenzi, V., Lovis, C., Magrin, D., Massa, A., Maxted, P. F. L., Nascimbeni, V., Olofsson, G., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Pollacco, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Ségransan, D., Simon, A. E., Smith, A. M. S., Steller, M., Szabó, Gy M., Thomas, N., Udry, S., Van Grootel, V., Verrecchia, F., Walton, N., Beck, T., Buder, M., Ratti, F., Ulmer, B., Viotto, V., Bourrier, V., Deline, A., Krenn, A., Egger, J. A., Petit, A. C., Malavolta, L., Cretignier, M., Billot, N., Broeg, C., Florén, H.-G., Queloz, D., Alibert, Y., Bonfanti, A., Bonomo, A. S., Delisle, J.-B., Demangeon, O. D. S., Demory, B.-O., Dumusque, X., Ehrenreich, D., Haywood, R. D., Howell, S. B., Lendl, M., Mortier, A., Nigro, G., Salmon, S., Sousa, S. G., Wilson, T. G., Adibekyan, V., Alonso, R., Anglada, G., Bárczy, T., Navascues, D. Barrado y, Barros, S. C. C., Baumjohann, W., Beck, M., Benz, W., Biondi, F., Bonfils, X., Brandeker, A., Cabrera, J., Charnoz, S., Csizmadia, Sz., Cameron, A. Collier, Damasso, M., Davies, M. B., Deleuil, M., Delrez, L., Di Fabrizio, L., Erikson, A., Fortier, A., Fossati, L., Fridlund, M., Gandolfi, D., Gillon, M., Güdel, M., Heng, K., Hoyer, S., Isaak, K. G., Kiss, L. L., Laskar, J., des Etangs, A. Lecavelier, Lorenzi, V., Lovis, C., Magrin, D., Massa, A., Maxted, P. F. L., Nascimbeni, V., Olofsson, G., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Pollacco, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Ségransan, D., Simon, A. E., Smith, A. M. S., Steller, M., Szabó, Gy M., Thomas, N., Udry, S., Van Grootel, V., Verrecchia, F., Walton, N., Beck, T., Buder, M., Ratti, F., Ulmer, B., and Viotto, V.

Abstract

Much remains to be understood about the nature of exoplanets smaller than Neptune, most of which have been discovered in compact multi-planet systems. With its inner ultra-short period planet b aligned with the star and two larger outer planets d-c on polar orbits, the multi-planet system HD 3167 features a peculiar architecture and offers the possibility to investigate both dynamical and atmospheric evolution processes. To this purpose we combined multiple datasets of transit photometry and radial velocimetry (RV) to revise the properties of the system and inform models of its planets. This effort was spearheaded by CHEOPS observations of HD 3167b, which appear inconsistent with a purely rocky composition despite its extreme irradiation. Overall the precision on the planetary orbital periods are improved by an order of magnitude, and the uncertainties on the densities of the transiting planets b and c are decreased by a factor of 3. Internal structure and atmospheric simulations draw a contrasting picture between HD 3167d, likely a rocky super-Earth that lost its atmosphere through photo-evaporation, and HD 3167c, a mini-Neptune that kept a substantial primordial gaseous envelope. We detect a fourth, more massive planet on a larger orbit, likely coplanar with HD 3167d-c. Dynamical simulations indeed show that the outer planetary system d-c-e was tilted, as a whole, early in the system history, when HD 3167b was still dominated by the star influence and maintained its aligned orbit. RV data and direct imaging rule out that the companion that could be responsible for the present-day architecture is still bound to the HD 3167 system. Similar global studies of multi-planet systems will tell how many share the peculiar properties of the HD 3167 system, which remains a target of choice for follow-up observations and simulations.

Published
2022

153. Fundamental effective temperature measurements for eclipsing binary stars – III. SPIRou near-infrared spectroscopy and CHEOPS photometry of the benchmark G0V star EBLM J0113+31

Author

Maxted, P F L, primary, Miller, N J, additional, Hoyer, S, additional, Adibekyan, V, additional, Sousa, S G, additional, Billot, N, additional, Fortier, A, additional, Simon, A E, additional, Cameron, A Collier, additional, Swayne, M I, additional, Gutermann, P, additional, Triaud, A H M J, additional, Southworth, J, additional, Alibert, Y, additional, Alonso, R, additional, Anglada, G, additional, Bárczy, T, additional, Navascues, D Barrado y, additional, Barros, S C C, additional, Baumjohann, W, additional, Beck, M, additional, Beck, T, additional, Benz, W, additional, Bonfils, X, additional, Brandeker, A, additional, Broeg, C, additional, Buder, M, additional, Cabrera, J, additional, Charnoz, S, additional, van Damme, C Corral, additional, Csizmadia, Sz, additional, Davies, M B, additional, Deleuil, M, additional, Delrez, L, additional, Demangeon, O, additional, Demory, B-O, additional, Ehrenreich, D, additional, Erikson, A, additional, Fossati, L, additional, Fridlund, M, additional, Gandolfi, D, additional, Gillon, M, additional, Güdel, M, additional, Heng, K, additional, Leon, J E Hernández, additional, Isaak, K G, additional, Kiss, L L, additional, Laskar, J, additional, Etangs, A Lecavelier des, additional, Lendl, M, additional, Lovis, C, additional, Magrin, D, additional, Munari, M, additional, Nascimbeni, V, additional, Olofsson, G, additional, Ottensamer, R, additional, Pagano, I, additional, Pallé, E, additional, Peter, G, additional, Piotto, G, additional, Pollacco, D, additional, Queloz, D, additional, Ragazzoni, R, additional, Rando, N, additional, Rauer, H, additional, Ribas, I, additional, Santos, N C, additional, Scandariato, G, additional, Ségransan, D, additional, Smith, A M S, additional, Steinberger, M, additional, Steller, M, additional, Szabó, Gy M, additional, Thomas, N, additional, Udry, S, additional, Van Grootel, V, additional, and Walton, N, additional

Published
2022
Full Text
View/download PDF

154. Transit timing variations of AU Microscopii b and c

Author

Szabó, Gy. M., primary, Garai, Z., additional, Brandeker, A., additional, Gandolfi, D., additional, Wilson, T. G., additional, Deline, A., additional, Olofsson, G., additional, Fortier, A., additional, Queloz, D., additional, Borsato, L., additional, Kiefer, F., additional, Lecavelier des Etangs, A., additional, Lendl, M., additional, Serrano, L. M., additional, Sulis, S., additional, Ulmer Moll, S., additional, Van Grootel, V., additional, Alibert, Y., additional, Alonso, R., additional, Anglada, G., additional, Bárczy, T., additional, Barrado y Navascues, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Beck, M., additional, Beck, T., additional, Benz, W., additional, Billot, N., additional, Bonfanti, A., additional, Bonfils, X., additional, Broeg, C., additional, Cabrera, J., additional, Charnoz, S., additional, Collier Cameron, A., additional, Csizmadia, Sz., additional, Davies, M. B., additional, Deleuil, M., additional, Delrez, L., additional, Demangeon, O., additional, Demory, B.-O., additional, Ehrenreich, D., additional, Erikson, A., additional, Fossati, L., additional, Fridlund, M., additional, Gillon, M., additional, Güdel, M., additional, Heng, K., additional, Hoyer, S., additional, Isaak, K. G., additional, Kiss, L. L., additional, Laskar, J., additional, Lovis, C., additional, Magrin, D., additional, Maxted, P. F. L., additional, Mecina, M., additional, Nascimbeni, V., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piotto, G., additional, Pollacco, D., additional, Ragazzoni, R., additional, Rando, N., additional, Rauer, H., additional, Ribas, I., additional, Santos, N. C., additional, Sarajlic, M., additional, Scandariato, G., additional, Ségransan, D., additional, Simon, A. E., additional, Smith, A. M. S., additional, Sousa, S. G., additional, Steller, M., additional, Thomas, N., additional, Udry, S., additional, Verrecchia, F., additional, Walton, N., additional, and Wolter, D., additional

Published
2022
Full Text
View/download PDF

155. The atmosphere and architecture of WASP-189 b probed by its CHEOPS phase curve

Author

Deline, A., primary, Hooton, M. J., additional, Lendl, M., additional, Morris, B., additional, Salmon, S., additional, Olofsson, G., additional, Broeg, C., additional, Ehrenreich, D., additional, Beck, M., additional, Brandeker, A., additional, Hoyer, S., additional, Sulis, S., additional, Van Grootel, V., additional, Bourrier, V., additional, Demangeon, O., additional, Demory, B.-O., additional, Heng, K., additional, Parviainen, H., additional, Serrano, L. M., additional, Singh, V., additional, Bonfanti, A., additional, Fossati, L., additional, Kitzmann, D., additional, Sousa, S. G., additional, Wilson, T. G., additional, Alibert, Y., additional, Alonso, R., additional, Anglada, G., additional, Bárczy, T., additional, Barrado Navascues, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Beck, T., additional, Bekkelien, A., additional, Benz, W., additional, Billot, N., additional, Bonfils, X., additional, Cabrera, J., additional, Charnoz, S., additional, Collier Cameron, A., additional, Corral van Damme, C., additional, Csizmadia, Sz., additional, Davies, M. B., additional, Deleuil, M., additional, Delrez, L., additional, de Roche, T., additional, Erikson, A., additional, Fortier, A., additional, Fridlund, M., additional, Futyan, D., additional, Gandolfi, D., additional, Gillon, M., additional, Güdel, M., additional, Gutermann, P., additional, Hasiba, J., additional, Isaak, K. G., additional, Kiss, L., additional, Laskar, J., additional, Lecavelier des Etangs, A., additional, Lovis, C., additional, Magrin, D., additional, Maxted, P. F. L., additional, Munari, M., additional, Nascimbeni, V., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piotto, G., additional, Pollacco, D., additional, Queloz, D., additional, Ragazzoni, R., additional, Rando, N., additional, Rauer, H., additional, Ribas, I., additional, Santos, N. C., additional, Scandariato, G., additional, Ségransan, D., additional, Simon, A. E., additional, Smith, A. M. S., additional, Steller, M., additional, Szabó, Gy. M., additional, Thomas, N., additional, Udry, S., additional, Walter, I., additional, and Walton, N., additional

Published
2022
Full Text
View/download PDF

156. CHEOPS geometric albedo of the hot Jupiter HD 209458 b

Author

Brandeker, A., primary, Heng, K., additional, Lendl, M., additional, Patel, J. A., additional, Morris, B. M., additional, Broeg, C., additional, Guterman, P., additional, Beck, M., additional, Maxted, P. F. L., additional, Demangeon, O., additional, Delrez, L., additional, Demory, B.-O., additional, Kitzmann, D., additional, Santos, N. C., additional, Singh, V., additional, Alibert, Y., additional, Alonso, R., additional, Anglada, G., additional, Bárczy, T., additional, Barrado y Navascues, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Beck, T., additional, Benz, W., additional, Billot, N., additional, Bonfils, X., additional, Bruno, G., additional, Cabrera, J., additional, Charnoz, S., additional, Collier Cameron, A., additional, Corral van Damme, C., additional, Csizmadia, Sz., additional, Davies, M. B., additional, Deleuil, M., additional, Deline, A., additional, Ehrenreich, D., additional, Erikson, A., additional, Farinato, J., additional, Fortier, A., additional, Fossati, L., additional, Fridlund, M., additional, Gandolfi, D., additional, Gillon, M., additional, Güdel, M., additional, Hoyer, S., additional, Isaak, K. G., additional, Kiss, L., additional, Laskar, J., additional, Lecavelier des Etangs, A., additional, Lovis, C., additional, Luntzer, A., additional, Magrin, D., additional, Nascimbeni, V., additional, Olofsson, G., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piotto, G., additional, Pollacco, D., additional, Queloz, D., additional, Ragazzoni, R., additional, Rando, N., additional, Rauer, H., additional, Ribas, I., additional, Scandariato, G., additional, Ségransan, D., additional, Simon, A. E., additional, Smith, A. M. S., additional, Sousa, S. G., additional, Steller, M., additional, Szabó, G. M., additional, Thomas, N., additional, Udry, S., additional, Van Grootel, V., additional, Walton, N., additional, and Wolter, D., additional

Published
2022
Full Text
View/download PDF

157. Detection of the tidal deformation of WASP-103b at 3 σ with CHEOPS

Author

Barros, S. C. C., Akinsanmi, B., Boué, G., Smith, A. M. S., Laskar, J., Ulmer-Moll, S., Lillo-Box, J., Queloz, D., Collier Cameron, A., Sousa, S. G., Ehrenreich, D., Hooton, M. J., Bruno, G., Demory, B.-O., Correia, A. C. M., Demangeon, O. D. S., Wilson, T. G., Bonfanti, A., Hoyer, S., Alibert, Y., Alonso, R., Anglada Escudé, G., Barbato, D., Bárczy, T., Barrado, D., Baumjohann, W., Beck, M., Beck, T., Benz, W., Bergomi, M., Billot, N., Bonfils, X., Bouchy, F., Brandeker, A., Broeg, C., Cabrera, J., Cessa, V., Charnoz, S., Damme, C. C. V., Davies, M. B., Deleuil, M., Deline, A., Delrez, L., Erikson, A., Fortier, A., Fossati, L., Fridlund, M., Gandolfi, D., García Muñoz, A., Gillon, M., Güdel, M., Isaak, K. G., Heng, Kevin, Kiss, L., Lecavelier des Etangs, A., Lendl, M., Lovis, C., Magrin, D., Nascimbeni, V., Maxted, P. F. L., Olofsson, G., Ottensamer, R., Pagano, I., Pallé, E., Parviainen, H., Peter, G., Piotto, G., Pollacco, Don, Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Salmon, S., Santos, N. C., Scandariato, G., Ségransan, D., Simon, A. E., Steller, M., Szabó, Gy. M., Thomas, N., Udry, S., Ulmer, B., Van Grootel, V., Walton, N. A., Fundação para a Ciência e a Tecnologia (Portugal), Science and Technology Facilities Council (UK), Swiss National Science Foundation, Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), European Research Council, Ministerio de Economía y Competitividad (España), European Commission, Generalitat de Catalunya, Fundación 'la Caixa', Junta de Andalucía, Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
530 Physics, fundamental parameters [Planets and satellites], Planets and satellites: interiors, Geometry, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Deformation (meteorology), Time, QB460, QB Astronomy, QA, QB600, Astrophysics::Galaxy Astrophysics, QC, QB, MCC, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 520 Astronomy, Computer Science::Information Retrieval, photometric [Techniques], Techniques: Photometric, Sigma, DAS, Astronomy and Astrophysics, Planets and satellites: individual: WASP-103b, 500 Science, 620 Engineering, interiors [Planets and satellites], Planets and satellites: fundamental parameters, Planets and satellites: composition, WASP-103b, QC Physics, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], composition [Planets and satellites], planets and satellites: fundamental parameters, planets and satellites: composition, planets and satellites: interiors, WASP-103b, ddc:520, Astrophysics::Earth and Planetary Astrophysics, individual: WASP-103b [Planets and satellites], QB799, Astrophysics - Earth and Planetary Astrophysics
Abstract

S. C. C. Barros et al., [Context] Ultra-short period planets undergo strong tidal interactions with their host star which lead to planet deformation and orbital tidal decay., [Aims] WASP-103b is the exoplanet with the highest expected deformation signature in its transit light curve and one of the shortest expected spiral-in times. Measuring the tidal deformation of the planet would allow us to estimate the second degree fluid Love number and gain insight into the planet’s internal structure. Moreover, measuring the tidal decay timescale would allow us to estimate the stellar tidal quality factor, which is key to constraining stellar physics., [Methods] We obtained 12 transit light curves of WASP-103b with the CHaracterising ExOplanet Satellite (CHEOPS) to estimate the tidal deformation and tidal decay of this extreme system. We modelled the high-precision CHEOPS transit light curves together with systematic instrumental noise using multi-dimensional Gaussian process regression informed by a set of instrumental parameters. To model the tidal deformation, we used a parametrisation model which allowed us to determine the second degree fluid Love number of the planet. We combined our light curves with previously observed transits of WASP-103b with the Hubble Space Telescope (HST) and Spitzer to increase the signal-to-noise of the light curve and better distinguish the minute signal expected from the planetary deformation., [Results] We estimate the radial Love number of WASP-103b to be hf = 1.59−0.53+0.45. This is the first time that the tidal deformation is directly detected (at 3 σ) from the transit light curve of an exoplanet. Combining the transit times derived from CHEOPS, HST, and Spitzer light curves with the other transit times available in the literature, we find no significant orbital period variation for WASP-103b. However, the data show a hint of an orbital period increase instead of a decrease, as is expected for tidal decay. This could be either due to a visual companion star if this star is bound, the Applegate effect, or a statistical artefact., [Conclusions] The estimated Love number of WASP-103b is similar to Jupiter’s. This will allow us to constrain the internal structure and composition of WASP-103b, which could provide clues on the inflation of hot Jupiters. Future observations with James Webb Space Telescope can better constrain the radial Love number of WASP-103b due to their high signal-to-noise and the smaller signature of limb darkening in the infrared. A longer time baseline is needed to constrain the tidal decay in this system., CHEOPS is an 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 CHEOPS Consortium would like to gratefully acknowledge the support received by all the agencies, offices, universities, and industries involved. Their flexibility and willingness to explore new approaches were essential to the success of this mission. This work was supported by FCT – Fundação para a Ciência e a Tecnologia through national funds and by FEDER through COMPETE2020 – Programa Operacional Competitividade e Internacionalizacão by these grants: UID/FIS/04434/2019, UIDB/04434/2020, UIDP/04434/2020, PTDC/FIS-AST/32113/2017 and POCI-01-0145-FEDER- 032113, PTDC/FIS-AST/28953/2017 and POCI-01-0145-FEDER-028953, PTDC/FIS-AST/28987/2017 and POCI-01- 0145-FEDER-028987, UIDB/04564/2020 UIDP/04564/2020, PTDC/FIS-AST/7002/2020, POCI-01-0145-FEDER-022217, POCI-01-0145-FEDER-029932. O.D.S.D. is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. S.G.S. acknowledges support from FCT through FCT contract nr. CEECIND/00826/2018 and POPH/FSE (EC). M.J.H. and Y.A. acknowledge the support of the Swiss National Fund under grant 200020_172746. S.H. gratefully acknowledges CNES funding through the grant 837319. D.K. acknowledges partial financial support from the Center for Space and Habitability (CSH), the PlanetS National Center of Competence in Research (NCCR), and the Swiss National Science Foundation and the Swiss-based MERAC Foundation. A.C.C. and T.G.W. acknowledge support from STFC consolidated grant number ST/M001296/1. P.M. acknowledges support from STFC research grant number ST/M001040/1. This work was also partially supported by a grant from the Simons Foundation (PI Queloz, grant number 327127). B.-O.D. acknowledges support from the Swiss National Science Foundation (PP00P2-190080). ABr was supported by the SNSA. We acknowledge support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grants ESP2016-80435-C2-1-R, ESP2016-80435-C2-2-R, PGC2018-098153-B-C33, PGC2018-098153-B-C31, ESP2017-87676-C5-1-R, MDM-2017-0737 Unidad de Excelencia Maria de Maeztu-Centro de Astrobiologí a (INTA-CSIC), as well as the support of the Generalitat de Catalunya/CERCA programme. The MOC activities have been supported by the ESA contract no. 4000124370. X.B., S.C., D.G., M.F., and J.L. acknowledge their roles as ESA-appointed CHEOPS science team members. This project was supported by the CNES. The Belgian participation to CHEOPS has been supported by the Belgian Federal Science Policy Office (BELSPO) in the framework of the PRODEX programme, and by the University of Liège through an ARC grant for Concerted Research Actions financed by the Wallonia-Brussels Federation. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project FOUR ACESgrant agreement no. 724427). C.M.P. and M.F. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18). DG gratefully acknowledges financial support from the Cassa di Risparmio di Torino (CRT) foundation under Grant No. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. M.G. is an F.R.S.-FNRS Senior Research Associate. KGI is the ESA CHEOPS Project Scientist and is responsible for the ESA CHEOPS Guest Observers Programme. She does not participate in, or contribute to, the definition of the Guaranteed Time Programme of the CHEOPS mission through which observations described in this paper have been taken, nor to any aspect of target selection for the programme. She acknowledges support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grant PGC2018-098153-B-C33, as well as the support of the Generalitat de Catalunya/CERCA programme. This project has been supported by the Hungarian National Research, Development and Innovation Office (NKFIH) grants GINOP-2.3.2-15-2016-00003, K-119517, K-125015, and the City of Szombathely under Agreement No. 67.177-21/2016. V.V.G. is an F.R.S.-FNRS Research Associate. J.L.-B. acknowledges financial support received from “la Caixa” Foundation (ID 100010434) and from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 847648, with fellowship code LCF/BQ/PI20/11760023. Based on observationscollected at Centro Astronómico Hispano en Andalucía (CAHA) at Calar Alto, operated jointly by Instituto de Astrofísica de Andalucía (CSIC) and Junta de Andalucía. G.B. acknowledges support from CHEOPS ASI-INAF agreement no. 2019-29-HH.0. M.L. acknowledges support from the Swiss National Science Foundation under Grant No. PCEFP2 194576. A.De. acknowledges the financial support of the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project FOUR ACES; grant agreement no. 724427). A.De. also acknowledges financial support of the Swiss National Science Foundation (SNSF) through the National Centre for Competence in Research “PlanetS”. L.D. is an F.R.S.-FNRS Postdoctoral Researcher.

Published
2022

158. Investigating the architecture and internal structure of the TOI-561 system planets with CHEOPS, HARPS-N, and TESS

Author

Lacedelli, G, Wilson, TG, Malavolta, L, Hooton, MJ, Collier Cameron, A, Alibert, Y, Mortier, A, Bonfanti, A, Haywood, RD, Hoyer, S, Piotto, G, Bekkelien, A, Vanderburg, AM, Benz, W, Dumusque, X, Deline, A, Lopez-Morales, M, Borsato, L, Rice, K, Fossati, L, Latham, DW, Brandeker, A, Poretti, E, Sousa, SG, Sozzetti, A, Salmon, S, Burke, CJ, Van Grootel, V, Fausnaugh, MM, Adibekyan, V, Huang, CX, Osborn, HP, Mustill, AJ, Palle, E, Bourrier, V, Nascimbeni, V, Alonso, R, Anglada, G, Barczy, T, Barrado Y Navascues, D, Barros, SCC, Baumjohann, W, Beck, M, Beck, T, Billot, N, Bonfils, X, Broeg, C, Buchhave, LA, Cabrera, J, Charnoz, S, Cosentino, R, Csizmadia, S, Davies, MB, Deleuil, M, Delrez, L, Demangeon, O, Demory, BO, Ehrenreich, D, Erikson, A, Esparza-Borges, E, Floren, HG, Fortier, A, Fridlund, M, Futyan, D, Gandolfi, D, Ghedina, A, Gillon, M, Güdel, M, Guterman, P, Harutyunyan, A, Heng, K, Isaak, KG, Jenkins, JM, Kiss, L, Laskar, J, Lecavelier Des Etangs, A, Lendl, M, Lovis, C, Magrin, D, Marafatto, L, Martinez Fiorenzano, AF, Maxted, PFL, Mayor, M, Micela, G, Molinari, E, Murgas, F, Narita, N, Olofsson, G, Ottensamer, R, Pagano, I, Pasetti, A, Pedani, M, Pepe, FA, Peter, G, Phillips, DF, Pollacco, D, Queloz, D, Ragazzoni, R, Rando, N, Ratti, F, Lacedelli, G [0000-0002-4197-7374], Wilson, TG [0000-0001-8749-1962], Malavolta, L [0000-0002-6492-2085], Hooton, MJ [0000-0003-0030-332X], Collier Cameron, A [0000-0002-8863-7828], Mortier, A [0000-0001-7254-4363], Borsato, L [0000-0003-0066-9268], Rice, K [0000-0002-6379-9185], Sousa, SG [0000-0001-9047-2965], Sozzetti, A [0000-0002-7504-365X], Osborn, HP [0000-0002-4047-4724], Mustill, AJ [0000-0002-2086-3642], Nascimbeni, V [0000-0001-9770-1214], Buchhave, LA [0000-0003-1605-5666], Csizmadia, S [0000-0001-6803-9698], Delrez, L [0000-0001-6108-4808], Gandolfi, D [0000-0001-8627-9628], Lendl, M [0000-0001-9699-1459], Maxted, PFL [0000-0003-3794-1317], and Apollo - University of Cambridge Repository

Subjects
techniques: photometric, stars: individual: TOI-561 (TIC 377064495, Gaia EDR3 3850421005290172416), techniques: radial velocities, planets and satellites: fundamental parameters, planets and satellites: interiors
Abstract

We present a precise characterization of the TOI-561 planetary system obtained by combining previously published data with TESS and CHEOPS photometry, and a new set of $62$ HARPS-N radial velocities (RVs). Our joint analysis confirms the presence of four transiting planets, namely TOI-561 b ($P = 0.45$ d, $R = 1.42$ R$_\oplus$, $M = 2.0$ M$_\oplus$), c ($P = 10.78$ d, $R = 2.91$ R$_\oplus$, $M = 5.4$ M$_\oplus$), d ($P = 25.7$ d, $R = 2.82$ R$_\oplus$, $M = 13.2$ M$_\oplus$) and e ($P = 77$ d, $R = 2.55$ R$_\oplus$, $M = 12.6$ M$_\oplus$). Moreover, we identify an additional, long-period signal ($>450$ d) in the RVs, which could be due to either an external planetary companion or to stellar magnetic activity. The precise masses and radii obtained for the four planets allowed us to conduct interior structure and atmospheric escape modelling. TOI-561 b is confirmed to be the lowest density ($\rho_{\rm b} = 3.8 \pm 0.5$ g cm$^{-3}$) ultra-short period (USP) planet known to date, and the low metallicity of the host star makes it consistent with the general bulk density-stellar metallicity trend. According to our interior structure modelling, planet b has basically no gas envelope, and it could host a certain amount of water. In contrast, TOI-561 c, d, and e likely retained an H/He envelope, in addition to a possibly large water layer. The inferred planetary compositions suggest different atmospheric evolutionary paths, with planets b and c having experienced significant gas loss, and planets d and e showing an atmospheric content consistent with the original one. The uniqueness of the USP planet, the presence of the long-period planet TOI-561 e, and the complex architecture make this system an appealing target for follow-up studies.

Published
2022

159. Spi-OPS: Spitzer and CHEOPS confirm the near-polar orbit of MASCARA-1 b and reveal a hint of dayside reflection

Author

Hooton, M. J., primary, Hoyer, S., additional, Kitzmann, D., additional, Morris, B. M., additional, Smith, A. M. S., additional, Collier Cameron, A., additional, Futyan, D., additional, Maxted, P. F. L., additional, Queloz, D., additional, Demory, B.-O., additional, Heng, K., additional, Lendl, M., additional, Cabrera, J., additional, Csizmadia, Sz., additional, Deline, A., additional, Parviainen, H., additional, Salmon, S., additional, Sulis, S., additional, Wilson, T. G., additional, Bonfanti, A., additional, Brandeker, A., additional, Demangeon, O. D. S., additional, Oshagh, M., additional, Persson, C. M., additional, Scandariato, G., additional, Alibert, Y., additional, Alonso, R., additional, Anglada Escudé, G., additional, Bárczy, T., additional, Barrado, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Beck, M., additional, Beck, T., additional, Benz, W., additional, Billot, N., additional, Bonfils, X., additional, Bourrier, V., additional, Broeg, C., additional, Busch, M.-D., additional, Charnoz, S., additional, Davies, M. B., additional, Deleuil, M., additional, Delrez, L., additional, Ehrenreich, D., additional, Erikson, A., additional, Farinato, J., additional, Fortier, A., additional, Fossati, L., additional, Fridlund, M., additional, Gandolfi, D., additional, Gillon, M., additional, Güdel, M., additional, Isaak, K. G., additional, Jones, K., additional, Kiss, L., additional, Laskar, J., additional, Lecavelier des Etangs, A., additional, Lovis, C., additional, Luntzer, A., additional, Magrin, D., additional, Nascimbeni, V., additional, Olofsson, G., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piotto, G., additional, Pollacco, D., additional, Ragazzoni, R., additional, Rando, N., additional, Ratti, F., additional, Rauer, H., additional, Ribas, I., additional, Santos, N. C., additional, Ségransan, D., additional, Simon, A. E., additional, Sousa, S. G., additional, Steller, M., additional, Szabó, Gy. M., additional, Thomas, N., additional, Udry, S., additional, Ulmer, B., additional, Van Grootel, V., additional, and Walton, N. A., additional

Published
2022
Full Text
View/download PDF

160. Investigating the architecture and internal structure of the TOI-561 system planets with CHEOPS, HARPS-N, and TESS

Author

Lacedelli, G, primary, Wilson, T G, additional, Malavolta, L, additional, Hooton, M J, additional, Collier Cameron, A, additional, Alibert, Y, additional, Mortier, A, additional, Bonfanti, A, additional, Haywood, R D, additional, Hoyer, S, additional, Piotto, G, additional, Bekkelien, A, additional, Vanderburg, A M, additional, Benz, W, additional, Dumusque, X, additional, Deline, A, additional, López-Morales, M, additional, Borsato, L, additional, Rice, K, additional, Fossati, L, additional, Latham, D W, additional, Brandeker, A, additional, Poretti, E, additional, Sousa, S G, additional, Sozzetti, A, additional, Salmon, S, additional, Burke, C J, additional, Van Grootel, V, additional, Fausnaugh, M M, additional, Adibekyan, V, additional, Huang, C X, additional, Osborn, H P, additional, Mustill, A J, additional, Pallé, E, additional, Bourrier, V, additional, Nascimbeni, V, additional, Alonso, R, additional, Anglada, G, additional, Bárczy, T, additional, Barrado y Navascues, D, additional, Barros, S C C, additional, Baumjohann, W, additional, Beck, M, additional, Beck, T, additional, Billot, N, additional, Bonfils, X, additional, Broeg, C, additional, Buchhave, L A, additional, Cabrera, J, additional, Charnoz, S, additional, Cosentino, R, additional, Csizmadia, Sz, additional, Davies, M B, additional, Deleuil, M, additional, Delrez, L, additional, Demangeon, O, additional, Demory, B -O, additional, Ehrenreich, D, additional, Erikson, A, additional, Esparza-Borges, E, additional, Florén, H G, additional, Fortier, A, additional, Fridlund, M, additional, Futyan, D, additional, Gandolfi, D, additional, Ghedina, A, additional, Gillon, M, additional, Güdel, M, additional, Guterman, P, additional, Harutyunyan, A, additional, Heng, K, additional, Isaak, K G, additional, Jenkins, J M, additional, Kiss, L, additional, Laskar, J, additional, Lecavelier des Etangs, A, additional, Lendl, M, additional, Lovis, C, additional, Magrin, D, additional, Marafatto, L, additional, Martinez Fiorenzano, A F, additional, Maxted, P F L, additional, Mayor, M, additional, Micela, G, additional, Molinari, E, additional, Murgas, F, additional, Narita, N, additional, Olofsson, G, additional, Ottensamer, R, additional, Pagano, I, additional, Pasetti, A, additional, Pedani, M, additional, Pepe, F A, additional, Peter, G, additional, Phillips, D F, additional, Pollacco, D, additional, Queloz, D, additional, Ragazzoni, R, additional, Rando, N, additional, Ratti, F, additional, Rauer, H, additional, Ribas, I, additional, Santos, N C, additional, Sasselov, D, additional, Scandariato, G, additional, Seager, S, additional, Ségransan, D, additional, Serrano, L M, additional, Simon, A E, additional, Smith, A M S, additional, Steinberger, M, additional, Steller, M, additional, Szabó, Gy, additional, Thomas, N, additional, Twicken, J D, additional, Udry, S, additional, Walton, N, additional, and Winn, J N, additional

Published
2022
Full Text
View/download PDF

161. The PLATO 2.0 mission

Author

Rauer, H., Catala, C., Aerts, C., Appourchaux, T., Benz, W., Brandeker, A., Christensen-Dalsgaard, J., Deleuil, M., Gizon, L., Goupil, M.-J., Güdel, M., Janot-Pacheco, E., Mas-Hesse, M., Pagano, I., Piotto, G., Pollacco, D., Santos, Ċ., Smith, A., Suárez, J.-C., Szabó, R., Udry, S., Adibekyan, V., Alibert, Y., Almenara, J.-M., Amaro-Seoane, P., Eiff, M. Ammler-von, Asplund, M., Antonello, E., Barnes, S., Baudin, F., Belkacem, K., Bergemann, M., Bihain, G., Birch, A. C., Bonfils, X., Boisse, I., Bonomo, A. S., Borsa, F., Brandão, I. M., Brocato, E., Brun, S., Burleigh, M., Burston, R., Cabrera, J., Cassisi, S., Chaplin, W., Charpinet, S., Chiappini, C., Church, R. P., Csizmadia, Sz., Cunha, M., Damasso, M., Davies, M. B., Deeg, H. J., Díaz, R. F., Dreizler, S., Dreyer, C., Eggenberger, P., Ehrenreich, D., Eigmüller, P., Erikson, A., Farmer, R., Feltzing, S., Oliveira Fialho, F. de, Figueira, P., Forveille, T., Fridlund, M., García, R. A., Giommi, P., Giuffrida, G., Godolt, M., da Silva, J. Gomes, Granzer, T., Grenfell, J. L., Grotsch-Noels, A., Günther, E., Haswell, C. A., Hatzes, A. P., Hébrard, G., Hekker, S., Helled, R., Heng, K., Jenkins, J. M., Johansen, A., Khodachenko, M. L., Kislyakova, K. G., Kley, W., Kolb, U., Krivova, N., Kupka, F., Lammer, H., Lanza, A. F., Lebreton, Y., Magrin, D., Marcos-Arenal, P., Marrese, P. M., Marques, J. P., Martins, J., Mathis, S., Mathur, S., Messina, S., Miglio, A., Montalban, J., Montalto, M., P. F. G. Monteiro, M. J., Moradi, H., Moravveji, E., Mordasini, C., Morel, T., Mortier, A., Nascimbeni, V., Nelson, R. P., Nielsen, M. B., Noack, L., Norton, A. J., Ofir, A., Oshagh, M., Ouazzani, R.-M., Pápics, P., Parro, V. C., Petit, P., Plez, B., Poretti, E., Quirrenbach, A., Ragazzoni, R., Raimondo, G., Rainer, M., Reese, D. R., Redmer, R., Reffert, S., Rojas-Ayala, B., Roxburgh, I. W., Salmon, S., Santerne, A., Schneider, J., Schou, J., Schuh, S., Schunker, H., Silva-Valio, A., Silvotti, R., Skillen, I., Snellen, I., Sohl, F., Sousa, S. G., Sozzetti, A., Stello, D., Strassmeier, K. G., Švanda, M., Szabó, Gy. M., Tkachenko, A., Valencia, D., Van Grootel, V., Vauclair, S. D., Ventura, P., Wagner, F. W., Walton, N. A., Weingrill, J., Werner, S. C., Wheatley, P. J., and Zwintz, K.

Published
2014
Full Text
View/download PDF

162. CHEOPS observations of the HD 108236 planetary system: A fifth planet, improved ephemerides, and planetary radii

Author

Bonfanti, A, Delrez, L, Hooton, MJ, Wilson, TG, Fossati, L, Alibert, Y, Hoyer, S, Mustill, AJ, Osborn, HP, Adibekyan, V, Gandolfi, D, Salmon, S, Sousa, SG, Tuson, A, Van Grootel, V, Cabrera, J, Nascimbeni, V, Maxted, PFL, Barros, SCC, Billot, N, Bonfils, X, Borsato, L, Broeg, C, Davies, MB, Deleuil, M, Demangeon, ODS, Fridlund, M, Lacedelli, G, Lendl, M, Persson, C, Santos, NC, Scandariato, G, Szabó, GM, Collier Cameron, A, Udry, S, Benz, W, Beck, M, Ehrenreich, D, Fortier, A, Isaak, KG, Queloz, D, Alonso, R, Asquier, J, Bandy, T, Bárczy, T, Barrado, D, Barragán, O, Baumjohann, W, Beck, T, Bekkelien, A, Bergomi, M, Brandeker, A, Busch, MD, Cessa, V, Charnoz, S, Chazelas, B, Corral Van Damme, C, Demory, BO, Erikson, A, Farinato, J, Futyan, D, Garcia Muñoz, A, Gillon, M, Guedel, M, Guterman, P, Hasiba, J, Heng, K, Hernandez, E, Kiss, L, Kuntzer, T, Laskar, J, Lecavelier Des Etangs, A, Lovis, C, Magrin, D, Malvasio, L, Marafatto, L, Michaelis, H, Munari, M, Olofsson, G, Ottacher, H, Ottensamer, R, Pagano, I, Pallé, E, Peter, G, Piazza, D, Piotto, G, Pollacco, D, Ragazzoni, R, Rando, N, Ratti, F, Rauer, H, Ribas, I, Rieder, M, Rohlfs, R, Safa, F, Salatti, M, Ségransan, D, Simon, AE, Smith, AMS, Sordet, M, Hooton, Matthew John [0000-0003-0030-332X], Queloz, Didier [0000-0002-3012-0316], and Apollo - University of Cambridge Repository

Subjects
planets and satellites: detection, stars: fundamental parameters, ephemerides, planets and satellites: fundamental parameters
Abstract

The detection of a super-Earth and three mini-Neptunes transiting the bright ($V$ = 9.2 mag) star HD 108236 (also known as TOI-1233) was recently reported on the basis of TESS and ground-based light curves. We perform a first characterisation of the HD 108236 planetary system through high-precision CHEOPS photometry and improve the transit ephemerides and system parameters. We characterise the host star through spectroscopic analysis and derive the radius with the infrared flux method. We constrain the stellar mass and age by combining the results obtained from two sets of stellar evolutionary tracks. We analyse the available TESS light curves and one CHEOPS transit light curve for each known planet in the system. We find that HD 108236 is a Sun-like star with $R_{\star}=0.877\pm0.008 R_{\odot}$, $M_{\star}=0.869^{+0.050}_{-0.048} M_{\odot}$, and an age of $6.7_{-5.1}^{+4.0}$ Gyr. We report the serendipitous detection of an additional planet, HD 108236 f, in one of the CHEOPS light curves. For this planet, the combined analysis of the TESS and CHEOPS light curves leads to a tentative orbital period of about 29.5 days. From the light curve analysis, we obtain radii of $1.615\pm0.051$, $2.071\pm0.052$, $2.539_{-0.065}^{+0.062}$, $3.083\pm0.052$, and $2.017_{-0.057}^{+0.052}$ $R_{\oplus}$ for planets HD 108236 b to HD 108236 f, respectively. These values are in agreement with previous TESS-based estimates, but with an improved precision of about a factor of two. We perform a stability analysis of the system, concluding that the planetary orbits most likely have eccentricities smaller than 0.1. We also employ a planetary atmospheric evolution framework to constrain the masses of the five planets, concluding that HD 108236 b and HD 108236 c should have an Earth-like density, while the outer planets should host a low mean molecular weight envelope.

Published
2021
Full Text
View/download PDF

163. The hot dayside and asymmetric transit of WASP-189 b seen by CHEOPS

Author

Lendl, M, Csizmadia, S, Deline, A, Fossati, L, Kitzmann, D, Heng, K, Hoyer, S, Salmon, S, Benz, W, Broeg, C, Ehrenreich, D, Fortier, A, Queloz, D, Bonfanti, A, Brandeker, A, Collier Cameron, A, Delrez, L, Garcia Muñoz, A, Hooton, MJ, Maxted, PFL, Morris, BM, Van Grootel, V, Wilson, TG, Alibert, Y, Alonso, R, Asquier, J, Bandy, T, Bárczy, T, Barrado, D, Barros, SCC, Baumjohann, W, Beck, M, Beck, T, Bekkelien, A, Bergomi, M, Billot, N, Biondi, F, Bonfils, X, Bourrier, V, Busch, MD, Cabrera, J, Cessa, V, Charnoz, S, Chazelas, B, Corral Van Damme, C, Davies, MB, Deleuil, M, Demangeon, ODS, Demory, BO, Erikson, A, Farinato, J, Fridlund, M, Futyan, D, Gandolfi, D, Gillon, M, Guterman, P, Hasiba, J, Hernandez, E, Isaak, KG, Kiss, L, Kuntzer, T, Lecavelier Des Etangs, A, Lüftinger, T, Laskar, J, Lovis, C, Magrin, D, Malvasio, L, Marafatto, L, Michaelis, H, Munari, M, Nascimbeni, V, Olofsson, G, Ottacher, H, Ottensamer, R, Pagano, I, Pallé, E, Peter, G, Piazza, D, Piotto, G, Pollacco, D, Ratti, F, Rauer, H, Ragazzoni, R, Rando, N, Ribas, I, Rieder, M, Rohlfs, R, Safa, F, Santos, NC, Scandariato, G, Ségransan, D, Simon, AE, Singh, V, Smith, AMS, Sordet, M, Sousa, SG, Steller, M, Szabó, GM, Thomas, N, Tschentscher, M, Queloz, Didier [0000-0002-3012-0316], Hooton, Matthew John [0000-0003-0030-332X], and Apollo - University of Cambridge Repository

Subjects
planets and satellites: atmospheres, techniques: photometric, planets and satellites: individual: WASP-189 b
Abstract

The CHEOPS space mission dedicated to exoplanet follow-up was launched in December 2019, equipped with the capacity to perform photometric measurements at the 20 ppm level. As CHEOPS carries out its observations in a broad optical passband, it can provide insights into the reflected light from exoplanets and constrain the short-wavelength thermal emission for the hottest of planets by observing occultations and phase curves. Here, we report the first CHEOPS observation of an occultation, namely, that of the hot Jupiter WASP-189b, a $M_P \approx 2 M_J$ planet orbiting an A-type star. We detected the occultation of WASP-189 b at high significance in individual measurements and derived an occultation depth of $dF = 87.9 \pm 4.3$ppm based on four occultations. We compared these measurements to model predictions and we find that they are consistent with an unreflective atmosphere heated to a temperature of $3435 \pm 27$K, when assuming inefficient heat redistribution. Furthermore, we present two transits of WASP-189b observed by CHEOPS. These transits have an asymmetric shape that we attribute to gravity darkening of the host star caused by its high rotation rate. We used these measurements to refine the planetary parameters, finding a $\sim25\%$ deeper transit compared to the discovery paper and updating the radius of WASP-189b to $1.619\pm0.021 R_J$. We further measured the projected orbital obliquity to be $\lambda = 86.4^{+2.9}_{-4.4}$deg, a value that is in good agreement with a previous measurement from spectroscopic observations, and derived a true obliquity of $\Psi = 85.4\pm4.3$deg. Finally, we provide reference values for the photometric precision attained by the CHEOPS satellite: for the V=6.6 mag star, and using a one-hour binning, we obtain a residual RMS between 10 and 17ppm on the individual light curves, and 5.7ppm when combining the four visits.

Published
2021
Full Text
View/download PDF

164. Analysis of Early Science observations with the CHaracterising ExOPlanets Satellite (CHEOPS) using pycheops

Author

Maxted, P F L, primary, Ehrenreich, D, additional, Wilson, T G, additional, Alibert, Y, additional, Cameron, A Collier, additional, Hoyer, S, additional, Sousa, S G, additional, Olofsson, G, additional, Bekkelien, A, additional, Deline, A, additional, Delrez, L, additional, Bonfanti, A, additional, Borsato, L, additional, Alonso, R, additional, Anglada Escudé, G, additional, Barrado, D, additional, Barros, S C C, additional, Baumjohann, W, additional, Beck, M, additional, Beck, T, additional, Benz, W, additional, Billot, N, additional, Biondi, F, additional, Bonfils, X, additional, Brandeker, A, additional, Broeg, C, additional, Bárczy, T, additional, Cabrera, J, additional, Charnoz, S, additional, Corral Van Damme, C, additional, Csizmadia, Sz, additional, Davies, M B, additional, Deleuil, M, additional, Demangeon, O D S, additional, Demory, B-O, additional, Erikson, A, additional, Florén, H G, additional, Fortier, A, additional, Fossati, L, additional, Fridlund, M, additional, Futyan, D, additional, Gandolfi, D, additional, Gillon, M, additional, Guedel, M, additional, Guterman, P, additional, Heng, K, additional, Isaak, K G, additional, Kiss, L, additional, Laskar, J, additional, Lecavelier des Etangs, A, additional, Lendl, M, additional, Lovis, C, additional, Magrin, D, additional, Nascimbeni, V, additional, Ottensamer, R, additional, Pagano, I, additional, Pallé, E, additional, Peter, G, additional, Piotto, G, additional, Pollacco, D, additional, Pozuelos, F J, additional, Queloz, D, additional, Ragazzoni, R, additional, Rando, N, additional, Rauer, H, additional, Reimers, C, additional, Ribas, I, additional, Salmon, S, additional, Santos, N C, additional, Scandariato, G, additional, Simon, A E, additional, Smith, A M S, additional, Steller, M, additional, Swayne, M I, additional, Szabó, Gy M, additional, Ségransan, D, additional, Thomas, N, additional, Udry, S, additional, Van Grootel, V, additional, and Walton, N A, additional

Published
2021
Full Text
View/download PDF

165. The changing face of AU Mic b: stellar spots, spin-orbit commensurability, and transit timing variations as seen by CHEOPS and TESS

Author

Szabó, Gy. M., primary, Gandolfi, D., additional, Brandeker, A., additional, Csizmadia, Sz., additional, Garai, Z., additional, Billot, N., additional, Broeg, C., additional, Ehrenreich, D., additional, Fortier, A., additional, Fossati, L., additional, Hoyer, S., additional, Kiss, L., additional, des Etangs, A. Lecavelier, additional, Maxted, P. F. L., additional, Ribas, I., additional, Alibert, Y., additional, Alonso, R., additional, Anglada Escudé, G., additional, Bárczy, T., additional, Barros, S. C. C., additional, Barrado, D., additional, Baumjohann, W., additional, Beck, M., additional, Beck, T., additional, Bekkelien, A., additional, Bonfils, X., additional, Benz, W., additional, Borsato, L., additional, Busch, M-D., additional, Cabrera, J., additional, Charnoz, S., additional, Collier Cameron, A., additional, Van Damme, C. Corral, additional, Davies, M. B., additional, Delrez, L., additional, Deleuil, M., additional, Demangeon, O. D. S., additional, Demory, B.-O., additional, Erikson, A., additional, Fridlund, M., additional, Futyan, D., additional, García Muñoz, A., additional, Gillon, M., additional, Guedel, M., additional, Guterman, P., additional, Heng, K., additional, Isaak, K. G., additional, Lacedelli, G., additional, Laskar, J., additional, Lendl, M., additional, Lovis, C., additional, Luntzer, A., additional, Magrin, D., additional, Nascimbeni, V., additional, Olofsson, G., additional, Osborn, H. P., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piazza, D., additional, Piotto, G., additional, Pollacco, D., additional, Queloz, D., additional, Ragazzoni, R., additional, Rando, N., additional, Rauer, H., additional, Santos, N. C., additional, Scandariato, G., additional, Ségransan, D., additional, Serrano, L. M., additional, Sicilia, D., additional, Simon, A. E., additional, Smith, A. M. S., additional, Sousa, S. G., additional, Steller, M., additional, Thomas, N., additional, Udry, S., additional, Van Grootel, V., additional, Walton, N. A., additional, and Wilson, T. G., additional

Published
2021
Full Text
View/download PDF

166. CHEOPS precision phase curve of the Super-Earth 55 Cancri e

Author

Morris, B. M., primary, Delrez, L., additional, Brandeker, A., additional, Cameron, A. C., additional, Simon, A. E., additional, Futyan, D., additional, Olofsson, G., additional, Hoyer, S., additional, Fortier, A., additional, Demory, B.-O., additional, Lendl, M., additional, Wilson, T. G., additional, Oshagh, M., additional, Heng, K., additional, Ehrenreich, D., additional, Sulis, S., additional, Alibert, Y., additional, Alonso, R., additional, Anglada Escudé, G., additional, Barrado, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Beck, M., additional, Beck, T., additional, Bekkelien, A., additional, Benz, W., additional, Bergomi, M., additional, Billot, N., additional, Bonfils, X., additional, Bourrier, V., additional, Broeg, C., additional, Bárczy, T., additional, Cabrera, J., additional, Charnoz, S., additional, Davies, M. B., additional, De Miguel Ferreras, D., additional, Deleuil, M., additional, Deline, A., additional, Demangeon, O. D. S., additional, Erikson, A., additional, Floren, H. G., additional, Fossati, L., additional, Fridlund, M., additional, Gandolfi, D., additional, García Muñoz, A., additional, Gillon, M., additional, Guedel, M., additional, Guterman, P., additional, Isaak, K., additional, Kiss, L., additional, Laskar, J., additional, Lecavelier des Etangs, A., additional, Lieder, M., additional, Lovis, C., additional, Magrin, D., additional, Maxted, P. F. L., additional, Nascimbeni, V., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piotto, G., additional, Pizarro Rubio, A., additional, Pollacco, D., additional, Pozuelos, F. J., additional, Queloz, D., additional, Ragazzoni, R., additional, Rando, N., additional, Rauer, H., additional, Ribas, I., additional, Santos, N. C., additional, Scandariato, G., additional, Smith, A. M. S., additional, Sousa, S. G., additional, Steller, M., additional, Szabó, Gy. M., additional, Ségransan, D., additional, Thomas, N., additional, Udry, S., additional, Ulmer, B., additional, Van Grootel, V., additional, and Walton, N. A., additional

Published
2021
Full Text
View/download PDF

167. A large sub-Neptune transiting the thick-disk M4 V TOI-2406

Author

Wells, R. D., primary, Rackham, B. V., additional, Schanche, N., additional, Petrucci, R., additional, Gómez Maqueo Chew, Y., additional, Demory, B.-O., additional, Burgasser, A. J., additional, Burn, R., additional, Pozuelos, F. J., additional, Günther, M. N., additional, Sabin, L., additional, Schroffenegger, U., additional, Gómez-Muñoz, M. A., additional, Stassun, K. G., additional, Van Grootel, V., additional, Howell, S. B., additional, Sebastian, D., additional, Triaud, A. H. M. J., additional, Apai, D., additional, Plauchu-Frayn, I., additional, Guerrero, C. A., additional, Guillén, P. F., additional, Landa, A., additional, Melgoza, G., additional, Montalvo, F., additional, Serrano, H., additional, Riesgo, H., additional, Barkaoui, K., additional, Bixel, A., additional, Burdanov, A., additional, Chen, W. P., additional, Chinchilla, P., additional, Collins, K. A., additional, Daylan, T., additional, de Wit, J., additional, Delrez, L., additional, Dévora-Pajares, M., additional, Dietrich, J., additional, Dransfield, G., additional, Ducrot, E., additional, Fausnaugh, M., additional, Furlan, E., additional, Gabor, P., additional, Gan, T., additional, Garcia, L., additional, Ghachoui, M., additional, Giacalone, S., additional, Gibbs, A. B., additional, Gillon, M., additional, Gnilka, C., additional, Gore, R., additional, Guerrero, N., additional, Henning, T., additional, Hesse, K., additional, Jehin, E., additional, Jenkins, J. M., additional, Latham, D. W., additional, Lester, K., additional, McCormac, J., additional, Murray, C. A., additional, Niraula, P., additional, Pedersen, P. P., additional, Queloz, D., additional, Ricker, G., additional, Rodriguez, D. R., additional, Schroeder, A., additional, Schwarz, R. P., additional, Scott, N., additional, Seager, S., additional, Theissen, C. A., additional, Thompson, S., additional, Timmermans, M., additional, Twicken, J. D., additional, and Winn, J. N., additional

Published
2021
Full Text
View/download PDF

168. A large oxygen-dominated core from the seismic cartography of a pulsating white dwarf

Author

Giammichele, N., Charpinet, S., Fontaine, G., Brassard, P., Green, E. M., Van Grootel, V., Bergeron, P., Zong, W., and Dupret, M.-A.

Subjects
Stratification (Geology) -- Measurement, White dwarfs -- Structure -- Composition, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Author(s): N. Giammichele (corresponding author) [1, 2]; S. Charpinet [1]; G. Fontaine [2]; P. Brassard [2]; E. M. Green [3]; V. Van Grootel [4]; P. Bergeron [2]; W. Zong [1, [...]

Published
2018
Full Text
View/download PDF

169. Exploiting timing capabilities of the CHEOPS mission with warm-Jupiter planets

Author

Borsato, L, primary, Piotto, G, additional, Gandolfi, D, additional, Nascimbeni, V, additional, Lacedelli, G, additional, Marzari, F, additional, Billot, N, additional, Maxted, P F L, additional, Sousa, S, additional, Cameron, A C, additional, Bonfanti, A, additional, Wilson, T G, additional, Serrano, L M, additional, Garai, Z, additional, Alibert, Y, additional, Alonso, R, additional, Asquier, J, additional, Bárczy, T, additional, Bandy, T, additional, Barrado, D, additional, Barros, S C C, additional, Baumjohann, W, additional, Beck, M, additional, Beck, T, additional, Benz, W, additional, Bonfils, X, additional, Brandeker, A, additional, Broeg, C, additional, Cabrera, J, additional, Charnoz, S, additional, Csizmadia, S, additional, Davies, M B, additional, Deleuil, M, additional, Delrez, L, additional, Demangeon, O, additional, Demory, B-O, additional, des Etangs, A L, additional, Ehrenreich, D, additional, Erikson, A, additional, Escudé, G A, additional, Fortier, A, additional, Fossati, L, additional, Fridlund, M, additional, Gillon, M, additional, Guedel, M, additional, Hasiba, J, additional, Heng, K, additional, Hoyer, S, additional, Isaak, K G, additional, Kiss, L, additional, Kopp, E, additional, Laskar, J, additional, Lendl, M, additional, Lovis, C, additional, Magrin, D, additional, Munari, M, additional, Olofsson, G, additional, Ottensamer, R, additional, Pagano, I, additional, Pallé, E, additional, Peter, G, additional, Pollacco, D, additional, Queloz, D, additional, Ragazzoni, R, additional, Rando, N, additional, Rauer, H, additional, Ribas, I, additional, Ségransan, D, additional, Santos, N C, additional, Scandariato, G, additional, Simon, A, additional, Smith, A M S, additional, Steller, M, additional, Szabó, G, additional, Thomas, N, additional, Udry, S, additional, Van Grootel, V, additional, and Walton, N, additional

Published
2021
Full Text
View/download PDF

170. The EBLM project – VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves

Author

Swayne, M I, primary, Maxted, P F L, additional, Triaud, A H M J, additional, Sousa, S G, additional, Broeg, C, additional, Florén, H-G, additional, Guterman, P, additional, Simon, A E, additional, Boisse, I, additional, Bonfanti, A, additional, Martin, D, additional, Santerne, A, additional, Salmon, S, additional, Standing, M R, additional, Van Grootel, V, additional, Wilson, T G, additional, Alibert, Y, additional, Alonso, R, additional, Anglada Escudé, G, additional, Asquier, J, additional, Bárczy, T, additional, Barrado, D, additional, Barros, S C C, additional, Battley, M, additional, Baumjohann, W, additional, Beck, M, additional, Beck, T, additional, Bekkelien, A, additional, Benz, W, additional, Billot, N, additional, Bonfils, X, additional, Brandeker, A, additional, Busch, M-D, additional, Cabrera, J, additional, Charnoz, S, additional, Collier Cameron, A, additional, Csizmadia, Sz, additional, Davies, M B, additional, Deleuil, M, additional, Deline, A, additional, Delrez, L, additional, Demangeon, O D S, additional, Demory, B-O, additional, Dransfield, G, additional, Ehrenreich, D, additional, Erikson, A, additional, Fortier, A, additional, Fossati, L, additional, Fridlund, M, additional, Futyan, D, additional, Gandolfi, D, additional, Gillon, M, additional, Guedel, M, additional, Hébrard, G, additional, Heidari, N, additional, Hellier, C, additional, Heng, K, additional, Hobson, M, additional, Hoyer, S, additional, Isaak, K G, additional, Kiss, L, additional, Kunovac Hodžić, V, additional, Lalitha, S, additional, Laskar, J, additional, Lecavelier des Etangs, A, additional, Lendl, M, additional, Lovis, C, additional, Magrin, D, additional, Marafatto, L, additional, McCormac, J, additional, Miller, N, additional, Nascimbeni, V, additional, Olofsson, G, additional, Ottensamer, R, additional, Pagano, I, additional, Pallé, E, additional, Peter, G, additional, Piotto, G, additional, Pollacco, D, additional, Queloz, D, additional, Ragazzoni, R, additional, Rando, N, additional, Rauer, H, additional, Ribas, I, additional, Santos, N C, additional, Scandariato, G, additional, Ségransan, D, additional, Smith, A M S, additional, Steinberger, M, additional, Steller, M, additional, Szabó, Gy M, additional, Thomas, N, additional, Udry, S, additional, Walter, I, additional, Walton, N A, additional, and Willett, E, additional

Published
2021
Full Text
View/download PDF

171. A search for transiting planets around hot subdwarfs

Author

Van Grootel, V., primary, Pozuelos, F. J., additional, Thuillier, A., additional, Charpinet, S., additional, Delrez, L., additional, Beck, M., additional, Fortier, A., additional, Hoyer, S., additional, Sousa, S. G., additional, Barlow, B. N., additional, Billot, N., additional, Dévora-Pajares, M., additional, Østensen, R. H., additional, Alibert, Y., additional, Alonso, R., additional, Anglada Escudé, G., additional, Asquier, J., additional, Barrado, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Beck, T., additional, Bekkelien, A., additional, Benz, W., additional, Bonfils, X., additional, Brandeker, A., additional, Broeg, C., additional, Bruno, G., additional, Bárczy, T., additional, Cabrera, J., additional, Cameron, A. C., additional, Charnoz, S., additional, Davies, M. B., additional, Deleuil, M., additional, Demangeon, O. D. S., additional, Demory, B.-O., additional, Ehrenreich, D., additional, Erikson, A., additional, Fossati, L., additional, Fridlund, M., additional, Futyan, D., additional, Gandolfi, D., additional, Gillon, M., additional, Guedel, M., additional, Heng, K., additional, Isaak, K. G., additional, Kiss, L., additional, Laskar, J., additional, Lecavelier des Etangs, A., additional, Lendl, M., additional, Lovis, C., additional, Magrin, D., additional, Maxted, P. F. L., additional, Mecina, M., additional, Mustill, A. J., additional, Nascimbeni, V., additional, Olofsson, G., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piotto, G., additional, Plesseria, J.-Y., additional, Pollacco, D., additional, Queloz, D., additional, Ragazzoni, R., additional, Rando, N., additional, Rauer, H., additional, Ribas, I., additional, Santos, N. C., additional, Scandariato, G., additional, Ségransan, D., additional, Silvotti, R., additional, Simon, A. E., additional, Smith, A. M. S., additional, Steller, M., additional, Szabó, G. M., additional, Thomas, N., additional, Udry, S., additional, Viotto, V., additional, Walton, N. A., additional, Westerdorff, K., additional, and Wilson, T. G., additional

Published
2021
Full Text
View/download PDF

172. enCHEOPS observations of the HD 108236 planetary system: a fifth planet, improved ephemerides, and planetary radii

Author

Bonfanti, A., Delrez, L., Hooton, M. J., Wilson, T. G., Fossati, L., Alibert, Y., Hoyer, S., Mustill, A. J., Osborn, H. P., Adibekyan, V., Gandolfi, D., Salmon, S., Sousa, S. G., Tuson, A., Van Grootel, V., Cabrera, J., Nascimbeni, V., Maxted, P. F. L., Barros, S. C. C., Billot, N., Bonfils, X., Borsato, L., Broeg, C., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Fridlund, M., Lacedelli, G., Lendl, M., Persson, C., Santos, N. C., Scandariato, G., Szabó, Gy. M., Collier Cameron, A., Udry, S., Benz, W., Beck, M., Ehrenreich, D., Fortier, A., Isaak, K. G., Queloz, D., Alonso, R., Asquier, J., Bandy, T., Bárczy, T., Barrado, D., Barragán, O., Baumjohann, W., Beck, T., Bekkelien, A., Bergomi, M., Brandeker, A., Busch, M.-D., Cessa, V., Charnoz, S., Chazelas, B., Corral Van Damme, C., Demory, B.-O., Erikson, A., Farinato, J., Futyan, D., Garcia Muñoz, A., Gillon, M., Guedel, M., Guterman, P., Hasiba, J., Heng, K., Hernandez, E., Kiss, L., Kuntzer, T., Laskar, J., Lecavelier des Etangs, A., Lovis, C., Magrin, D., Malvasio, L., Marafatto, L., Michaelis, H., Munari, M., Olofsson, G., Ottacher, H., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piazza, D., Piotto, G., Pollacco, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Ribas, I., Rieder, M., Rohlfs, R., Safa, F., Salatti, M., Ségransan, D., Simon, A. E., Smith, A. M. S., Sordet, M., Steller, M., Thomas, N., Tschentscher, M., Van Eylen, V., Viotto, V., Walter, I., Walton, N. A., Wildi, F., and Wolter, D.

Subjects
530 Physics, 520 Astronomy, 620 Engineering
Abstract

Context. The detection of a super-Earth and three mini-Neptunes transiting the bright (V = 9.2 mag) star HD 108236 (also known as TOI-1233) was recently reported on the basis of TESS and ground-based light curves. Aims. We perform a first characterisation of the HD 108236 planetary system through high-precision CHEOPS photometry and improve the transit ephemerides and system parameters. Methods. We characterise the host star through spectroscopic analysis and derive the radius with the infrared flux method. We constrain the stellar mass and age by combining the results obtained from two sets of stellar evolutionary tracks. We analyse the available TESS light curves and one CHEOPS transit light curve for each known planet in the system. Results. We find that HD 108236 is a Sun-like star with R⋆ = 0.877 ± 0.008 R⊙, M⋆ = 0.869−0.048+0.050 M⊙, and an age of 6.7−5.1+4.0 Gyr. We report the serendipitous detection of an additional planet, HD 108236 f, in one of the CHEOPS light curves. For this planet, the combined analysis of the TESS and CHEOPS light curves leads to a tentative orbital period of about 29.5 days. From the light curve analysis, we obtain radii of 1.615 ± 0.051, 2.071 ± 0.052, 2.539−0.065+0.062, 3.083 ± 0.052, and 2.017−0.057+0.052 R⊕ for planets HD 108236 b to HD 108236 f, respectively. These values are in agreement with previous TESS-based estimates, but with an improved precision of about a factor of two. We perform a stability analysis of the system, concluding that the planetary orbits most likely have eccentricities smaller than 0.1. We also employ a planetary atmospheric evolution framework to constrain the masses of the five planets, concluding that HD 108236 b and HD 108236 c should have an Earth-like density, while the outer planets should host a low mean molecular weight envelope. Conclusions. The detection of the fifth planet makes HD 108236 the third system brighter than V = 10 mag to host more than four transiting planets. The longer time span enables us to significantly improve the orbital ephemerides such that the uncertainty on the transit times will be of the order of minutes for the years to come. A comparison of the results obtained from the TESS and CHEOPS light curves indicates that for a V ~ 9 mag solar-like star and a transit signal of ~500 ppm, one CHEOPS transit light curve ensures the same level of photometric precision as eight TESS transits combined, although this conclusion depends on the length and position of the gaps in the light curve.

Published
2021

173. The EBLM project-VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves

Author

Swayne, MI, Maxted, PFL, Triaud, AHMJ, Sousa, SG, Broeg, C, Florén, HG, Guterman, P, Simon, AE, Boisse, I, Bonfanti, A, Martin, D, Santerne, A, Salmon, S, Standing, MR, Van Grootel, V, Wilson, TG, Alibert, Y, Alonso, R, Anglada Escudé, G, Asquier, J, Bárczy, T, Barrado, D, Barros, SCC, Battley, M, Baumjohann, W, Beck, M, Beck, T, Bekkelien, A, Benz, W, Billot, N, Bonfils, X, Brandeker, A, Busch, MD, Cabrera, J, Charnoz, S, Collier Cameron, A, Csizmadia, S, Davies, MB, Deleuil, M, Deline, A, Delrez, L, Demangeon, ODS, Demory, BO, Dransfield, G, Ehrenreich, D, Erikson, A, Fortier, A, Fossati, L, Fridlund, M, Futyan, D, Gandolfi, D, Gillon, M, Guedel, M, Hébrard, G, Heidari, N, Hellier, C, Heng, K, Hobson, M, Hoyer, S, Isaak, KG, Kiss, L, Kunovac Hodžić, V, Lalitha, S, Laskar, J, Lecavelier Des Etangs, A, Lendl, M, Lovis, C, Magrin, D, Marafatto, L, McCormac, J, Miller, N, Nascimbeni, V, Olofsson, G, Ottensamer, R, Pagano, I, Pallé, E, Peter, G, Piotto, G, Pollacco, D, Queloz, D, Ragazzoni, R, Rando, N, Rauer, H, Ribas, I, Santos, NC, Scandariato, G, Ségransan, D, Smith, AMS, Steinberger, M, Steller, M, Szabó, GM, Thomas, N, Udry, S, Walter, I, Walton, NA, Willett, E, Swayne, MI [0000-0002-2609-3159], Triaud, AHMJ [0000-0002-5510-8751], Sousa, SG [0000-0001-9047-2965], Santerne, A [0000-0002-3586-1316], Wilson, TG [0000-0001-8749-1962], Battley, M [0000-0002-1357-9774], Baumjohann, W [0000-0001-6271-0110], Collier Cameron, A [0000-0002-8863-7828], Csizmadia, S [0000-0001-6803-9698], Delrez, L [0000-0001-6108-4808], Fridlund, M [0000-0002-0855-8426], Gandolfi, D [0000-0001-8627-9628], Hoyer, S [0000-0003-3477-2466], Lendl, M [0000-0001-9699-1459], Miller, N [0000-0001-9550-1198], and Apollo - University of Cambridge Repository

Subjects
techniques: photometric, stars: low-mass, Astrophysics::Solar and Stellar Astrophysics, binaries: eclipsing, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, stars: fundamental parameters, Astrophysics::Galaxy Astrophysics, techniques: spectroscopic
Abstract

The accuracy of theoretical mass, radius and effective temperature values for M-dwarf stars is an active topic of debate. Differences between observed and theoretical values have raised the possibility that current theoretical stellar structure and evolution models are inaccurate towards the low-mass end of the main sequence. To explore this issue we use the CHEOPS satellite to obtain high-precision light curves of eclipsing binaries with low mass stellar companions. We use these light curves combined with the spectroscopic orbit for the solar-type companion to measure the mass, radius and effective temperature of the M-dwarf star. Here we present the analysis of three eclipsing binaries. We use the pycheops data analysis software to fit the observed transit and eclipse events of each system. Two of our systems were also observed by the TESS satellite -- we similarly analyse these light curves for comparison. We find consistent results between CHEOPS and TESS, presenting three stellar radii and two stellar effective temperature values of low-mass stellar objects. These initial results from our on-going observing programme with CHEOPS show that we can expect to have ~24 new mass, radius and effective temperature measurements for very low mass stars within the next few years.

Published
2021

174. I. Methods and performance tests on light curves from Kepler , K2, TESS, and CHEOPS

Author

Van Grootel, V., Pozuelos, F. J., Thuillier, A., Charpinet, S., Delrez, L., Beck, M., Fortier, A., Hoyer, S., Sousa, S. G., Barlow, B. N., Billot, N., D��vora-Pajares, M., ��stensen, R. H., Alibert, Y., Alonso, R., Anglada Escud��, G., Asquier, J., Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, T., Bekkelien, A., Benz, W., Bonfils, X., Brandeker, A., Broeg, C., Bruno, G., B��rczy, T., Cabrera, J., Cameron, A. C., Charnoz, S., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Demory, B.-O., Ehrenreich, D., Erikson, A., Fossati, L., Fridlund, M., Futyan, D., Gandolfi, D., Gillon, M., Guedel, M., Heng, K., Isaak, K. G., Kiss, L., Laskar, J., Lecavelier des Etangs, A., Lendl, M., Lovis, C., Magrin, D., Maxted, P. F. L., Mecina, M., Mustill, A. J., Nascimbeni, V., Olofsson, G., Ottensamer, R., Pagano, I., Pall��, E., Peter, G., Piotto, G., Plesseria, J.-Y., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., S��gransan, D., Silvotti, R., Simon, A. E., Smith, A. M. S., Steller, M., Szab��, G. M., Thomas, N., Udry, S., Viotto, V., Walton, N. A., Westerdorff, K., Wilson, T. G., Space sciences, Technologies and Astrophysics Research (STAR) Institute, Université de Liège, Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), European Space Research and Technology Centre (ESTEC), Agence Spatiale Européenne = European Space Agency (ESA), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre Spatial de Liège (CSL), ANR-17-CE31-0018,INSIDE,Inversion astérosismique de la stratification en carbone / oxygène des noyaux d'étoiles de faible masse évoluées(2017), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Cavendish Laboratory, University of Cambridge [UK] (CAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Instituto de Astrofísica e Ciências do Espaço (IASTRO), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Université de Genève (UNIGE), European Space Agency (ESA), Institut de Physique du Globe de Paris (IPGP), and Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)

Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 520 Astronomy, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Q1, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 620 Engineering, QB600, QC, Astrophysics::Galaxy Astrophysics, QB, QB799
Abstract

Context. Hot subdwarfs experienced strong mass loss on the red giant branch (RGB) and are now hot and small He-burning objects. These stars constitute excellent opportunities for addressing the question of the evolution of exoplanetary systems directly after the RGB phase of evolution.\ud \ud Aims. In this project we aim to perform a transit survey in all available light curves of hot subdwarfs from space-based telescopes (Kepler, K2, TESS, and CHEOPS) with our custom-made pipeline SHERLOCK in order to determine the occurrence rate of planets around these stars as a function of orbital period and planetary radius. We also aim to determine whether planets that were previously engulfed in the envelope of their red giant host star can survive, even partially, as a planetary remnant.\ud \ud Methods. For this first paper, we performed injection-and-recovery tests of synthetic transits for a selection of representative Kepler, K2, and TESS light curves to determine which transiting bodies in terms of object radius and orbital period we will be able to detect with our tools. We also provide estimates for CHEOPS data, which we analyzed with the pycheops package.\ud \ud Results. Transiting objects with a radius less than or similar to 1.0 R-circle times can be detected in most of the Kepler, K2, and CHEOPS targets for the shortest orbital periods (1 d and shorter), reaching values as low as similar to 0.3 R-circle times in the best cases. Sub-Earth-sized bodies are only reached for the brightest TESS targets and for those that were observed in a significant number of sectors. We also give a series of representative results for larger planets at greater distances, which strongly depend on the target magnitude and on the length and quality of the data.\ud \ud Conclusions. The TESS sample will provide the most important statistics for the global aim of measuring the planet occurrence rate around hot subdwarfs. The Kepler, K2, and CHEOPS data will allow us to search for planetary remnants, that is, very close and small (possibly disintegrating) objects.

Published
2021
Full Text
View/download PDF

175. SPECULOOS: Ultracool dwarf transit survey

Author

Sebastian, D., Gillon, M., Ducrot, E., Pozuelos, F. J., Garcia, L. J., Günther, M. N., Delrez, L., Queloz, D., Demory, B. O., Triaud, A. H. M. J., Burgasser, A., de Wit, J., Burdanov, A., Dransfield, G., Jehin, E., McCormac, J., Murray, C. A., Niraula, P., Pedersen, P. P., Rackham, B. V., Sohy, S., Thompson, S., and Van Grootel, V.

Subjects
520 Astronomy, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Context. One of the most promising avenues for the detailed study of temperate Earth-sized exoplanets is the detection of such planets in transit in front of stars that are small and near enough to make it possible to carry out a thorough atmospheric characterisation with next-generation telescopes, such as the James Webb Space telescope (JWST) or Extremely Large Telescope (ELT). In this context, the TRAPPIST-1 planets form a unique benchmark system that has garnered the interest of a large scientific community. Aims. The SPECULOOS survey is an exoplanet transit survey targeting a volume-limited (40 pc) sample of ultracool dwarf stars (of spectral type M7 and later) that is based on a network of robotic 1 m telescopes especially designed for this survey. The strategy for brighter and earlier targets leverages on the synergy with the ongoing TESS space-based exoplanet transit survey. Methods. We define the SPECULOOS target list as the sum of three non-overlapping sub-programmes incorporating the latest type objects (Teff ≲ 3000 K). Programme 1 features 365 dwarfs that are small and near enough to make it possible to detail atmospheric characterisation of an ‘Earth-like’ planet with the upcoming JWST. Programme 2 features 171 dwarfs of M5-type and later for which a significant detection of a planet similar to TRAPPIST-1b should be within reach of TESS. Programme 3 features 1121 dwarfs that are later than M6-type. These programmes form the basis of our statistical census of short-period planets around ultracool dwarf stars. Results. Our compound target list includes 1657 photometrically classified late-type dwarfs, with 260 of these targets classified, for the first time, as possible nearby ultracool dwarf stars. Our general observational strategy was to monitor each target between 100 and 200 h with our telescope network, making efficient use of the synergy with TESS for our Programme 2 targets and a proportion of targets in our Programme 1. Conclusions. Based on Monte Carlo simulations, we expect to detect up to a few dozen temperate, rocky planets. We also expect a number of them to prove amenable for atmospheric characterisation with JWST and other future giant telescopes, which will substantially improve our understanding of the planetary population of the latest-type stars.

Published
2021
Full Text
View/download PDF

176. The EBLM project – VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves

Author

Swayne, M., Maxted, P. F. L., Triaud, A. H. M. J., Sousa, S. G., Broeg, C., Florén, Hans Gustav Axel, Guterman, P., Simon, A. E., Boisse, I., Bonfanti, A., Martin, D., Santerne, A., Salmon, S., Standing, M. R., Van Grootel, V., Wilson, T. G., Alibert, Y., Alonso, R., Anglada Escudé, G., Asquier, J., Bárczy, T., Barrado, D., Barros, S. C. C., Battley, M., Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Benz, W., Billot, N., Bonfils, X., Brandeker, Alexis, Busch, M.-D., Cabrera, J., Charnoz, S., Collier Cameron, A., Csizmadia, Sz., Davies, M. B., Deleuil, M., Deline, A., Delrez, L., Demangeon, O. D. S., Demory, B.-O., Dransfield, G., Ehrenreich, D., Erikson, A., Fortier, A., Fossati, L., Fridlund, M., Futyan, D., Gandolfi, D., Gillon, M., Guedel, M., Hébrard, G., Heidari, N., Hellier, C., Heng, K., Hobson, M., Hoyer, S., Isaak, K. G., Kiss, L., Kunovac Hodžić, V., Lalitha, S., Laskar, J., Lecavelier des Etangs, A., Lendl, M., Lovis, C., Magrin, D., Marafatto, L., McCormac, J., Miller, N., Nascimbeni, V., Olofsson, Göran, Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Ségransan, D., Smith, A. M. S., Steinberger, M., Steller, M., Szabó, Gy. M., Thomas, N., Udry, S., Walter, I., Walton, N. A., Willett, E., Swayne, M., Maxted, P. F. L., Triaud, A. H. M. J., Sousa, S. G., Broeg, C., Florén, Hans Gustav Axel, Guterman, P., Simon, A. E., Boisse, I., Bonfanti, A., Martin, D., Santerne, A., Salmon, S., Standing, M. R., Van Grootel, V., Wilson, T. G., Alibert, Y., Alonso, R., Anglada Escudé, G., Asquier, J., Bárczy, T., Barrado, D., Barros, S. C. C., Battley, M., Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Benz, W., Billot, N., Bonfils, X., Brandeker, Alexis, Busch, M.-D., Cabrera, J., Charnoz, S., Collier Cameron, A., Csizmadia, Sz., Davies, M. B., Deleuil, M., Deline, A., Delrez, L., Demangeon, O. D. S., Demory, B.-O., Dransfield, G., Ehrenreich, D., Erikson, A., Fortier, A., Fossati, L., Fridlund, M., Futyan, D., Gandolfi, D., Gillon, M., Guedel, M., Hébrard, G., Heidari, N., Hellier, C., Heng, K., Hobson, M., Hoyer, S., Isaak, K. G., Kiss, L., Kunovac Hodžić, V., Lalitha, S., Laskar, J., Lecavelier des Etangs, A., Lendl, M., Lovis, C., Magrin, D., Marafatto, L., McCormac, J., Miller, N., Nascimbeni, V., Olofsson, Göran, Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Ségransan, D., Smith, A. M. S., Steinberger, M., Steller, M., Szabó, Gy. M., Thomas, N., Udry, S., Walter, I., Walton, N. A., and Willett, E.

Abstract

The accuracy of theoretical mass, radius, and effective temperature values for M-dwarf stars is an active topic of debate. Differences between observed and theoretical values have raised the possibility that current theoretical stellar structure and evolution models are inaccurate towards the low-mass end of the main sequence. To explore this issue, we use the CHEOPS satellite to obtain high-precision light curves of eclipsing binaries with low-mass stellar companions. We use these light curves combined with the spectroscopic orbit for the solar-type companion to measure the mass, radius, and effective temperature of the M-dwarf star. Here, we present the analysis of three eclipsing binaries. We use the PYCHEOPS data analysis software to fit the observed transit and eclipse events of each system. Two of our systems were also observed by the TESS satellite – we similarly analyse these light curves for comparison. We find consistent results between CHEOPS and TESS, presenting three stellar radii and two stellar effective temperature values of low-mass stellar objects. These initial results from our on-going observing programme with CHEOPS show that we can expect to have ∼24 new mass, radius, and effective temperature measurements for very low-mass stars within the next few years.

Published
2021
Full Text
View/download PDF

177. The changing face of AU Mic b : stellar spots, spin-orbit commensurability, and transit timing variations as seen by CHEOPS and TESS

Author

Szabo, Gy M., Gandolfi, D., Brandeker, Alexis, Csizmadia, Sz, Garai, Z., Billot, N., Broeg, C., Ehrenreich, D., Fortier, A., Fossati, L., Hoyer, S., Kiss, L., Lecavelier des Etangs, A., Maxted, P. F. L., Ribas, I., Alibert, Y., Alonso, R., Anglada Escude, G., Barczy, T., Barros, S. C. C., Barrado, D., Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Bonfils, X., Benz, W., Borsato, L., Busch, M.-D., Cabrera, J., Charnoz, S., Collier Cameron, A., Corral Van Damme, C., Davies, M. B., Delrez, L., Deleuil, M., Demangeon, O. D. S., Demory, B.-O., Erikson, A., Fridlund, M., Futyan, D., Garcia Munoz, A., Gillon, M., Guedel, M., Guterman, P., Heng, K., Isaak, K. G., Lacedelli, G., Laskar, J., Lendl, M., Lovis, C., Luntzer, A., Magrin, D., Nascimbeni, V., Olofsson, Göran, Osborn, H. P., Ottensamer, R., Pagano, I., Palle, E., Peter, G., Piazza, D., Piotto, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Santos, N. C., Scandariato, G., Segransan, D., Serrano, L. M., Sicilia, D., Simon, A. E., Smith, A. M. S., Sousa, S. G., Steller, M., Thomas, N., Udry, S., Van Grootel, V., Walton, N. A., Wilson, T. G., Szabo, Gy M., Gandolfi, D., Brandeker, Alexis, Csizmadia, Sz, Garai, Z., Billot, N., Broeg, C., Ehrenreich, D., Fortier, A., Fossati, L., Hoyer, S., Kiss, L., Lecavelier des Etangs, A., Maxted, P. F. L., Ribas, I., Alibert, Y., Alonso, R., Anglada Escude, G., Barczy, T., Barros, S. C. C., Barrado, D., Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Bonfils, X., Benz, W., Borsato, L., Busch, M.-D., Cabrera, J., Charnoz, S., Collier Cameron, A., Corral Van Damme, C., Davies, M. B., Delrez, L., Deleuil, M., Demangeon, O. D. S., Demory, B.-O., Erikson, A., Fridlund, M., Futyan, D., Garcia Munoz, A., Gillon, M., Guedel, M., Guterman, P., Heng, K., Isaak, K. G., Lacedelli, G., Laskar, J., Lendl, M., Lovis, C., Luntzer, A., Magrin, D., Nascimbeni, V., Olofsson, Göran, Osborn, H. P., Ottensamer, R., Pagano, I., Palle, E., Peter, G., Piazza, D., Piotto, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Santos, N. C., Scandariato, G., Segransan, D., Serrano, L. M., Sicilia, D., Simon, A. E., Smith, A. M. S., Sousa, S. G., Steller, M., Thomas, N., Udry, S., Van Grootel, V., Walton, N. A., and Wilson, T. G.

Abstract

AU Mic is a young planetary system with a resolved debris disc showing signs of planet formation and two transiting warm Neptunes near mean-motion resonances. Here we analyse three transits of AU Mic b observed with the CHaracterising ExOPlanet Satellite (CHEOPS), supplemented with sector 1 and 27 Transiting Exoplanet Survey Satellite (TESS) photometry, and the All-Sky Automated Survey from the ground. The refined orbital period of AU Mic b is 8.462995 +/- 0.000003 d, whereas the stellar rotational period is P-rot = 4.8367 +/- 0.0006 d. The two periods indicate a 7:4 spin-orbit commensurability at a precision of 0.1%. Therefore, all transits are observed in front of one of the four possible stellar central longitudes. This is strongly supported by the observation that the same complex star-spot pattern is seen in the second and third CHEOPS visits that were separated by four orbits (and seven stellar rotations). Using a bootstrap analysis we find that flares and star spots reduce the accuracy of transit parameters by up to 10% in the planet-to-star radius ratio and the accuracy on transit time by 3-4 min. Nevertheless, occulted stellar spot features independently confirm the presence of transit timing variations (TTVs) with an amplitude of at least 4 min. We find that the outer companion, AU Mic c, may cause the observed TTVs.

Published
2021
Full Text
View/download PDF

178. Exploiting timing capabilities of the CHEOPS mission with warm-Jupiter planets

Author

Borsato, L., Piotto, G., Gandolfi, D., Nascimbeni, V, Lacedelli, G., Marzari, F., Billot, N., Maxted, P. F. L., Sousa, S., Cameron, A. C., Bonfanti, A., Wilson, T. G., Serrano, L. M., Garai, Z., Alibert, Y., Alonso, R., Asquier, J., Bárczy, T., Bandy, T., Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, M., Beck, T., Benz, W., Bonfils, X., Brandeker, Alexis, Broeg, C., Cabrera, J., Charnoz, S., Csizmadia, S., Davies, M. B., Deleuil, M., Delrez, L., Demangeon, O., Demory, B-O, des Etangs, A. L., Ehrenreich, D., Erikson, A., Escudé, G. A., Fortier, A., Fossati, L., Fridlund, M., Gillon, M., Guedel, M., Hasiba, J., Heng, K., Hoyer, S., Isaak, K. G., Kiss, L., Kopp, E., Laskar, J., Lendl, M., Lovis, C., Magrin, D., Munari, M., Olofsson, Göran, Ottensamer, R., Pagano, I, Pallé, E., Peter, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I, Ségransan, D., Santos, N. C., Scandariato, G., Simon, A., Smith, A. M. S., Steller, M., Szabó, G., Thomas, N., Udry, S., Van Grootel, V., Walton, N., Borsato, L., Piotto, G., Gandolfi, D., Nascimbeni, V, Lacedelli, G., Marzari, F., Billot, N., Maxted, P. F. L., Sousa, S., Cameron, A. C., Bonfanti, A., Wilson, T. G., Serrano, L. M., Garai, Z., Alibert, Y., Alonso, R., Asquier, J., Bárczy, T., Bandy, T., Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, M., Beck, T., Benz, W., Bonfils, X., Brandeker, Alexis, Broeg, C., Cabrera, J., Charnoz, S., Csizmadia, S., Davies, M. B., Deleuil, M., Delrez, L., Demangeon, O., Demory, B-O, des Etangs, A. L., Ehrenreich, D., Erikson, A., Escudé, G. A., Fortier, A., Fossati, L., Fridlund, M., Gillon, M., Guedel, M., Hasiba, J., Heng, K., Hoyer, S., Isaak, K. G., Kiss, L., Kopp, E., Laskar, J., Lendl, M., Lovis, C., Magrin, D., Munari, M., Olofsson, Göran, Ottensamer, R., Pagano, I, Pallé, E., Peter, G., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I, Ségransan, D., Santos, N. C., Scandariato, G., Simon, A., Smith, A. M. S., Steller, M., Szabó, G., Thomas, N., Udry, S., Van Grootel, V., and Walton, N.

Abstract

We present 17 transit light curves of seven known warm-Jupiters observed with the CHaracterising ExOPlanet Satellite (CHEOPS). The light curves have been collected as part of the CHEOPS Guaranteed Time Observation (GTO) program that searches for transit-timing variation (TTV) of warm-Jupiters induced by a possible external perturber to shed light on the evolution path of such planetary systems. We describe the CHEOPS observation process, from the planning to the data analysis. In this work, we focused on the timing performance of CHEOPS, the impact of the sampling of the transit phases, and the improvement we can obtain by combining multiple transits together. We reached the highest precision on the transit time of about 13–16 s for the brightest target (WASP-38, G = 9.2) in our sample. From the combined analysis of multiple transits of fainter targets with G ≥ 11, we obtained a timing precision of ∼2 min. Additional observations with CHEOPS, covering a longer temporal baseline, will further improve the precision on the transit times and will allow us to detect possible TTV signals induced by an external perturber.

Published
2021
Full Text
View/download PDF

179. A search for transiting planets around hot subdwarfs I. Methods and performance tests on light curves from Kepler, K2, TESS, and CHEOPS

Author

Van Grootel, V., Pozuelos, F. J., Thuillier, A., Charpinet, S., Delrez, L., Beck, M., Fortier, A., Hoyer, S., Sousa, S. G., Barlow, B. N., Billot, N., Dévora-Pajares, M., Østensen, R. H., Alibert, Y., Alonso, R., Anglada Escudé, G., Asquier, J., Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, T., Bekkelien, A., Benz, W., Bonfils, X., Brandeker, Alexis, Broeg, C., Bruno, G., Bárczy, T., Cabrera, J., Cameron, A. C., Charnoz, S., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Demory, B-O., Ehrenreich, D., Erikson, A., Fossati, L., Fridlund, M., Futyan, D., Gandolfi, D., Gillon, M., Guedel, M., Heng, K., Isaak, K. G., Kiss, L., Laskar, J., Lecavelier des Etangs, A., Lendl, M., Lovis, C., Magrin, D., Maxted, P. F. L., Mecina, M., Mustill, A. J., Nascimbeni, V., Olofsson, Göran, Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Plesseria, J-Y., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Ségransan, D., Silvotti, R., Simon, A. E., Smith, A. M. S., Steller, M., Szabó, G. M., Thomas, N., Udry, S., Viotto, V., Walton, N. A., Westerdorff, K., Wilson, T. G., Van Grootel, V., Pozuelos, F. J., Thuillier, A., Charpinet, S., Delrez, L., Beck, M., Fortier, A., Hoyer, S., Sousa, S. G., Barlow, B. N., Billot, N., Dévora-Pajares, M., Østensen, R. H., Alibert, Y., Alonso, R., Anglada Escudé, G., Asquier, J., Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, T., Bekkelien, A., Benz, W., Bonfils, X., Brandeker, Alexis, Broeg, C., Bruno, G., Bárczy, T., Cabrera, J., Cameron, A. C., Charnoz, S., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Demory, B-O., Ehrenreich, D., Erikson, A., Fossati, L., Fridlund, M., Futyan, D., Gandolfi, D., Gillon, M., Guedel, M., Heng, K., Isaak, K. G., Kiss, L., Laskar, J., Lecavelier des Etangs, A., Lendl, M., Lovis, C., Magrin, D., Maxted, P. F. L., Mecina, M., Mustill, A. J., Nascimbeni, V., Olofsson, Göran, Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Plesseria, J-Y., Pollacco, D., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Ségransan, D., Silvotti, R., Simon, A. E., Smith, A. M. S., Steller, M., Szabó, G. M., Thomas, N., Udry, S., Viotto, V., Walton, N. A., Westerdorff, K., and Wilson, T. G.

Abstract

Context. Hot subdwarfs experienced strong mass loss on the red giant branch (RGB) and are now hot and small He-burning objects. These stars constitute excellent opportunities for addressing the question of the evolution of exoplanetary systems directly after the RGB phase of evolution. Aims. In this project we aim to perform a transit survey in all available light curves of hot subdwarfs from space-based telescopes (Kepler, K2, TESS, and CHEOPS) with our custom-made pipeline SHERLOCK in order to determine the occurrence rate of planets around these stars as a function of orbital period and planetary radius. We also aim to determine whether planets that were previously engulfed in the envelope of their red giant host star can survive, even partially, as a planetary remnant. Methods. For this first paper, we performed injection-and-recovery tests of synthetic transits for a selection of representative Kepler, K2, and TESS light curves to determine which transiting bodies in terms of object radius and orbital period we will be able to detect with our tools. We also provide estimates for CHEOPS data, which we analyzed with the pycheops package. Results. Transiting objects with a radius ≲1.0 R⊕ can be detected in most of the Kepler, K2, and CHEOPS targets for the shortest orbital periods (1 d and shorter), reaching values as low as ~0.3 R⊕ in the best cases. Sub-Earth-sized bodies are only reached for the brightest TESS targets and for those that were observed in a significant number of sectors. We also give a series of representative results for larger planets at greater distances, which strongly depend on the target magnitude and on the length and quality of the data. Conclusions. The TESS sample will provide the most important statistics for the global aim of measuring the planet occurrence rate around hot subdwarfs. The Kepler, K2, and CHEOPS data will allow us to search for planetary remnants, that is, very close and small (possibly disintegrating) objects.

Published
2021
Full Text
View/download PDF

180. A large sub-Neptune transiting the thick-disk M4V TOI-2406

Author

Wells, R. D., Rackham, B. V., Schanche, N., Petrucci, R., Chew, Y. Gomez Maqueo, Demory, B. -O., Burgasser, A. J., Burn, R., Pozuelos, F. J., Gunther, M. N., Sabin, L., Schroffenegger, U., Gomez-Munoz, M. A., Stassun, K. G., Van Grootel, V., Howell, S. B., Sebastian, D., Triaud, A. H. M. J., Apai, D., Plauchu-Frayn, I., Guerrero, C. A., Guillen, P. F., Landa, A., Melgoza, G., Montalvo, F., Serrano, H., Riesgo, H., Barkaoui, K., Bixel, A., Burdanov, A., Chen, W. P., Chinchilla, P., Collins, K. A., Daylan, T., de Wit, J., Delrez, L., Devora-Pajares, M., Dietrich, J., Dransfield, G., Ducrot, E., Fausnaugh, M., Furlan, E., Gabor, P., Gan, T., Garcia, L., Ghachoui, M., Giacalone, S., Gibbs, A. B., Gillon, M., Gnilka, C., Gore, R., Guerrero, N., Henning, T., Hesse, K., Jehin, E., Jenkins, J. M., Latham, D. W., Lester, K., McCormac, J., Murray, C. A., Niraula, P., Pedersen, P. P., Queloz, D., Ricker, G., Rodriguez, D. R., Schroeder, A., Schwarz, R. P., Scott, N., Seager, S., Theissen, C. A., Thompson, S., Timmermans, M., Twicken, J. D., Winn, J. N., Wells, R. D., Rackham, B. V., Schanche, N., Petrucci, R., Chew, Y. Gomez Maqueo, Demory, B. -O., Burgasser, A. J., Burn, R., Pozuelos, F. J., Gunther, M. N., Sabin, L., Schroffenegger, U., Gomez-Munoz, M. A., Stassun, K. G., Van Grootel, V., Howell, S. B., Sebastian, D., Triaud, A. H. M. J., Apai, D., Plauchu-Frayn, I., Guerrero, C. A., Guillen, P. F., Landa, A., Melgoza, G., Montalvo, F., Serrano, H., Riesgo, H., Barkaoui, K., Bixel, A., Burdanov, A., Chen, W. P., Chinchilla, P., Collins, K. A., Daylan, T., de Wit, J., Delrez, L., Devora-Pajares, M., Dietrich, J., Dransfield, G., Ducrot, E., Fausnaugh, M., Furlan, E., Gabor, P., Gan, T., Garcia, L., Ghachoui, M., Giacalone, S., Gibbs, A. B., Gillon, M., Gnilka, C., Gore, R., Guerrero, N., Henning, T., Hesse, K., Jehin, E., Jenkins, J. M., Latham, D. W., Lester, K., McCormac, J., Murray, C. A., Niraula, P., Pedersen, P. P., Queloz, D., Ricker, G., Rodriguez, D. R., Schroeder, A., Schwarz, R. P., Scott, N., Seager, S., Theissen, C. A., Thompson, S., Timmermans, M., Twicken, J. D., and Winn, J. N.

Abstract

Large sub-Neptunes are uncommon around the coolest stars in the Galaxy and are rarer still around those that are metal-poor. However, owing to the large planet-to-star radius ratio, these planets are highly suitable for atmospheric study via transmission spectroscopy in the infrared, such as with JWST. Here we report the discovery and validation of a sub-Neptune orbiting the thick-disk, mid-M dwarf star TOI-2406. We first infer properties of the host star by analysing the star's near-infrared spectrum, spectral energy distribution, and Gaia parallax. We use multi-band photometry to confirm that the transit event is on-target and achromatic, and we statistically validate the TESS signal as a transiting exoplanet. We then determine physical properties of the planet through global transit modelling of the TESS and ground-based time-series data. We determine the host to be a metal-poor M4V star, located at a distance of 56 pc, with a sub-solar metallicity $(\mathrm{[Fe/H] = -0.38 \pm 0.07})$, and a member of the thick disk. The planet is a relatively large sub-Neptune for the M-dwarf planet population, with $\mathrm{R_p = 2.94 \pm 0.17} \mathrm{R_\oplus}$ and $\mathrm{P = 3.077}$ d, producing transits of 2% depth. We note the orbit has a non-zero eccentricity to 3$\mathrm{\sigma}$, prompting questions about the dynamical history of the system. This system is an interesting outcome of planet formation and presents a benchmark for large-planet formation around metal-poor, low-mass stars. The system warrants further study, in particular radial velocity follow-up to determine the planet mass and constrain possible bound companions. Furthermore, TOI-2406 b is a good target for future atmospheric study through transmission spectroscopy, particularly in the category of warm sub-Neptunes., Comment: Accepted for publication in Astronomy and Astrophysics

Published
2021
Full Text
View/download PDF

181. Toward a systematic cartography of the chemical stratification inside white dwarfs from deep asteroseismic probing of ZZ Ceti stars

Author

Charpinet, S., Giammichele, N., Brassard, P., Fontaine, G., Bergeron, P., Zong, W., Van Grootel, V., Baran, A. S., Charpinet, S., Giammichele, N., Brassard, P., Fontaine, G., Bergeron, P., Zong, W., Van Grootel, V., and Baran, A. S.

Abstract

DA-type white dwarfs account for 80% of all white dwarfs and represent, for most of them, the ultimate outcome of the typical evolution of low-to-intermediate mass stars. Their internal chemical stratification is strongly marked by passed, often uncertain, stellar evolution processes that occurred during the helium (core and shell) burning phases, i.e., from the horizontal branch through AGB and post-AGB stages. Pulsating white dwarfs, in particular the "cool" DA-type ZZ Ceti variables, offer an outstanding opportunity to dig into these stars by fully exploiting their asteroseismic potential. With our most recent tools dedicated to that purpose, we show that a complete cartography of the stratification of the main constituents of a white dwarf can be inferred, leading in particular to strong constraints on the C/O core structure produced by the processes mentioned above. This opens up the way toward a systematic exploration of white-dwarf internal properties., Comment: 5 pages, 3 figures, 21st European Workshop on White Dwarfs, ed. Castanheira, Campos, & Montgomery

Published
2021

182. CHEOPS Precision Phase Curve of the Super-Earth 55 Cnc e

Author

Morris, B. M., Delrez, L., Brandeker, A., Cameron, A. C., Simon, A. E., Futyan, D., Olofsson, G., Hoyer, S., Fortier, A., Demory, B. -O., Lendl, M., Wilson, T. G., Oshagh, M., Heng, K., Ehrenreich, D., Sulis, S., Alibert, Y., Alonso, R., Escudé, G. Anglada, Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Benz, W., Bergomi, M., Billot, N., Bonfils, X., Bourrier, V., Broeg, C., Bárczy, T., Cabrera, J., Charnoz, S., Davies, M. B., Ferreras, D. De Miguel, Deleuil, M., Deline, A., Demangeon, O. D. S., Erikson, A., Floren, H. G., Fossati, L., Fridlund, M., Gandolfi, D., Muñoz, A. García, Gillon, M., Guedel, M., Guterman, P., Isaak, K., Kiss, L., Laskar, J., Etangs, A. Lecavelier des, Lieder, M., Lovis, C., Magrin, D., Maxted, P. F. L., Nascimbeni, V., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Rubio, A. Pizarro, Pollacco, D., Pozuelos, F. J., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Smith, A. M. S., Sousa, S. G., Steller, M., Szabó, Gy. M., Ségransan, D., Thomas, N., Udry, S., Ulmer, B., Van Grootel, V., Walton, N. A., Morris, B. M., Delrez, L., Brandeker, A., Cameron, A. C., Simon, A. E., Futyan, D., Olofsson, G., Hoyer, S., Fortier, A., Demory, B. -O., Lendl, M., Wilson, T. G., Oshagh, M., Heng, K., Ehrenreich, D., Sulis, S., Alibert, Y., Alonso, R., Escudé, G. Anglada, Barrado, D., Barros, S. C. C., Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Benz, W., Bergomi, M., Billot, N., Bonfils, X., Bourrier, V., Broeg, C., Bárczy, T., Cabrera, J., Charnoz, S., Davies, M. B., Ferreras, D. De Miguel, Deleuil, M., Deline, A., Demangeon, O. D. S., Erikson, A., Floren, H. G., Fossati, L., Fridlund, M., Gandolfi, D., Muñoz, A. García, Gillon, M., Guedel, M., Guterman, P., Isaak, K., Kiss, L., Laskar, J., Etangs, A. Lecavelier des, Lieder, M., Lovis, C., Magrin, D., Maxted, P. F. L., Nascimbeni, V., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Rubio, A. Pizarro, Pollacco, D., Pozuelos, F. J., Queloz, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Santos, N. C., Scandariato, G., Smith, A. M. S., Sousa, S. G., Steller, M., Szabó, Gy. M., Ségransan, D., Thomas, N., Udry, S., Ulmer, B., Van Grootel, V., and Walton, N. A.

Abstract

55 Cnc e is a transiting super-Earth (radius $1.88\rm\,R_\oplus$ and mass $8\rm\, M_\oplus$) orbiting a G8V host star on a 17-hour orbit. Spitzer observations of the planet's phase curve at 4.5 $\mu$m revealed a time-varying occultation depth, and MOST optical observations are consistent with a time-varying phase curve amplitude and phase offset of maximum light. Both broadband and high-resolution spectroscopic analyses are consistent with either a high mean molecular weight atmosphere or no atmosphere for planet e. A long term photometric monitoring campaign on an independent optical telescope is needed to probe the variability in this system. We seek to measure the phase variations of 55 Cnc e with a broadband optical filter with the 30 cm effective aperture space telescope CHEOPS and explore how the precision photometry narrows down the range of possible scenarios. We observed 55 Cnc for 1.6 orbital phases in March of 2020. We designed a phase curve detrending toolkit for CHEOPS photometry which allows us to study the underlying flux variations of the 55 Cnc system. We detected a phase variation with a full-amplitude of $72 \pm 7$ ppm but do not detect a significant secondary eclipse of the planet. The shape of the phase variation resembles that of a piecewise-Lambertian, however the non-detection of the planetary secondary eclipse, and the large amplitude of the variations exclude reflection from the planetary surface as a possible origin of the observed phase variations. They are also likely incompatible with magnetospheric interactions between the star and planet but may imply that circumplanetary or circumstellar material modulate the flux of the system. Further precision photometry of 55 Cnc from CHEOPS will measure variations in the phase curve amplitude and shape over time this year., Comment: 15 pages, accepted by A&A

Published
2021
Full Text
View/download PDF

183. Six transiting planets and a chain of Laplace resonances in TOI-178

Author

Leleu, A., Alibert, Y., Hara, N. C., Hooton, M. J., Wilson, T. G., Robutel, P., Delisle, J. -B., Laskar, J., Hoyer, S., Lovis, C., Bryant, E. M., Ducrot, E., Cabrera, J., Delrez, L., Acton, J. S., Adibekyan, V., Allart, R., Prieto, C. Allende, Alonso, R., Alves, D., Anderson, D. R., Angerhausen, D., Escudé, G. Anglada, Asquier, J., Barrado, D., Barros, S. C. C., Baumjohann, W., Bayliss, D., Beck, M., Beck, T., Bekkelien, A., Benz, W., Billot, N., Bonfanti, A., Bonfils, X., Bouchy, F., Bourrier, V., Boué, G., Brandeker, A., Broeg, C., Buder, M., Burdanov, A., Burleigh, M. R., Bárczy, T., Cameron, A. C., Chamberlain, S., Charnoz, S., Cooke, B. F., Van Damme, C. Corral, Correia, A. C. M., Cristiani, S., Damasso, M., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Demory, B. -O., Di Marcantonio, P., Di Persio, G., Dumusque, X., Ehrenreich, D., Erikson, A., Figueira, P., Fortier, A., Fossati, L., Fridlund, M., Futyan, D., Gandolfi, D., Muñoz, A. García, Garcia, L. J., Gill, S., Gillen, E., Gillon, M., Goad, M. R., Hernández, J. I. González, Guedel, M., Günther, M. N., Haldemann, J., Henderson, B., Heng, K., Hogan, A. E., Isaak, K., Jehin, E., Jenkins, J. S., Jordán, A., Kiss, L., Kristiansen, M. H., Lam, K., Lavie, B., Etangs, A. Lecavelier des, Lendl, M., Lillo-Box, J., Curto, G. Lo, Magrin, D., Martins, C. J. A. P., Maxted, P. F. L., McCormac, J., Mehner, A., Micela, G., Molaro, P., Moyano, M., Murray, C. A., Nascimbeni, V., Nunes, N. J., Olofsson, G., Osborn, H. P., Oshagh, M., Ottensamer, R., Pagano, I., Pallé, E., Pedersen, P. P., Pepe, F. A., Persson, C. M., Peter, G., Piotto, G., Polenta, G., Pollacco, D., Poretti, E., Pozuelos, F. J., Queloz, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Raynard, L., Rebolo, R., Reimers, C., Ribas, I., Santos, N. C., Scandariato, G., Schneider, J., Sebastian, D., Sestovic, M., Simon, A. E., Smith, A. M. S., Sousa, S. G., Sozzetti, A., Steller, M., Mascareño, A. Suárez, Szabó, Gy. M., Ségransan, D., Thomas, N., Thompson, S., Tilbrook, R. H., Triaud, A., Turner, O., Udry, S., Van Grootel, V., Venus, H., Verrecchia, F., Vines, J. I., Walton, N. A., West, R. G., Wheatley, P. J., Wolter, D., Osorio, M. R. Zapatero, Leleu, A., Alibert, Y., Hara, N. C., Hooton, M. J., Wilson, T. G., Robutel, P., Delisle, J. -B., Laskar, J., Hoyer, S., Lovis, C., Bryant, E. M., Ducrot, E., Cabrera, J., Delrez, L., Acton, J. S., Adibekyan, V., Allart, R., Prieto, C. Allende, Alonso, R., Alves, D., Anderson, D. R., Angerhausen, D., Escudé, G. Anglada, Asquier, J., Barrado, D., Barros, S. C. C., Baumjohann, W., Bayliss, D., Beck, M., Beck, T., Bekkelien, A., Benz, W., Billot, N., Bonfanti, A., Bonfils, X., Bouchy, F., Bourrier, V., Boué, G., Brandeker, A., Broeg, C., Buder, M., Burdanov, A., Burleigh, M. R., Bárczy, T., Cameron, A. C., Chamberlain, S., Charnoz, S., Cooke, B. F., Van Damme, C. Corral, Correia, A. C. M., Cristiani, S., Damasso, M., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Demory, B. -O., Di Marcantonio, P., Di Persio, G., Dumusque, X., Ehrenreich, D., Erikson, A., Figueira, P., Fortier, A., Fossati, L., Fridlund, M., Futyan, D., Gandolfi, D., Muñoz, A. García, Garcia, L. J., Gill, S., Gillen, E., Gillon, M., Goad, M. R., Hernández, J. I. González, Guedel, M., Günther, M. N., Haldemann, J., Henderson, B., Heng, K., Hogan, A. E., Isaak, K., Jehin, E., Jenkins, J. S., Jordán, A., Kiss, L., Kristiansen, M. H., Lam, K., Lavie, B., Etangs, A. Lecavelier des, Lendl, M., Lillo-Box, J., Curto, G. Lo, Magrin, D., Martins, C. J. A. P., Maxted, P. F. L., McCormac, J., Mehner, A., Micela, G., Molaro, P., Moyano, M., Murray, C. A., Nascimbeni, V., Nunes, N. J., Olofsson, G., Osborn, H. P., Oshagh, M., Ottensamer, R., Pagano, I., Pallé, E., Pedersen, P. P., Pepe, F. A., Persson, C. M., Peter, G., Piotto, G., Polenta, G., Pollacco, D., Poretti, E., Pozuelos, F. J., Queloz, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Raynard, L., Rebolo, R., Reimers, C., Ribas, I., Santos, N. C., Scandariato, G., Schneider, J., Sebastian, D., Sestovic, M., Simon, A. E., Smith, A. M. S., Sousa, S. G., Sozzetti, A., Steller, M., Mascareño, A. Suárez, Szabó, Gy. M., Ségransan, D., Thomas, N., Thompson, S., Tilbrook, R. H., Triaud, A., Turner, O., Udry, S., Van Grootel, V., Venus, H., Verrecchia, F., Vines, J. I., Walton, N. A., West, R. G., Wheatley, P. J., Wolter, D., and Osorio, M. R. Zapatero

Abstract

Determining the architecture of multi-planetary systems is one of the cornerstones of understanding planet formation and evolution. Resonant systems are especially important as the fragility of their orbital configuration ensures that no significant scattering or collisional event has taken place since the earliest formation phase when the parent protoplanetary disc was still present. In this context, TOI-178 has been the subject of particular attention since the first TESS observations hinted at a 2:3:3 resonant chain. Here we report the results of observations from CHEOPS, ESPRESSO, NGTS, and SPECULOOS with the aim of deciphering the peculiar orbital architecture of the system. We show that TOI-178 harbours at least six planets in the super-Earth to mini-Neptune regimes, with radii ranging from 1.152(-0.070/+0.073) to 2.87(-0.13/+0.14) Earth radii and periods of 1.91, 3.24, 6.56, 9.96, 15.23, and 20.71 days. All planets but the innermost one form a 2:4:6:9:12 chain of Laplace resonances, and the planetary densities show important variations from planet to planet, jumping from 1.02(+0.28/-0.23) to 0.177(+0.055/-0.061) times the Earth's density between planets c and d. Using Bayesian interior structure retrieval models, we show that the amount of gas in the planets does not vary in a monotonous way, contrary to what one would expect from simple formation and evolution models and unlike other known systems in a chain of Laplace resonances. The brightness of TOI-178 allows for a precise characterisation of its orbital architecture as well as of the physical nature of the six presently known transiting planets it harbours. The peculiar orbital configuration and the diversity in average density among the planets in the system will enable the study of interior planetary structures and atmospheric evolution, providing important clues on the formation of super-Earths and mini-Neptunes.

Published
2021
Full Text
View/download PDF

184. CHEOPS observations of the HD 108236 planetary system: A fifth planet, improved ephemerides, and planetary radii

Author

Bonfanti, A., Delrez, L., Hooton, M. J., Wilson, T. G., Fossati, L., Alibert, Y., Hoyer, S., Mustill, A. J., Osborn, H. P., Adibekyan, V., Gandolfi, D., Salmon, S., Sousa, S. G., Tuson, A., Van Grootel, V., Cabrera, J., Nascimbeni, V., Maxted, P. F. L., Barros, S. C. C., Billot, N., Bonfils, X., Borsato, L., Broeg, C., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Fridlund, M., Lacedelli, G., Lendl, M., Persson, C., Santos, N. C., Scandariato, G., Szabó, Gy. M., Cameron, A. Collier, Udry, S., Benz, W., Beck, M., Ehrenreich, D., Fortier, A., Isaak, K. G., Queloz, D., Alonso, R., Asquier, J., Bandy, T., Bárczy, T., Barrado, D., Barragán, O., Baumjohann, W., Beck, T., Bekkelien, A., Bergomi, M., Busch, M-D., Brandeker, A., Cessa, V., Charnoz, S., Chazelas, B., Van Damme, C. Corral, Demory, B. -O., Erikson, A., Farinato, J., Futyan, D., Muñoz, A. Garcia, Gillon, M., Guedel, M., Guterman, P., Hasiba, J., Heng, K., Hernandez, E., Kiss, L., Kuntzer, T., Laskar, J., Etangs, A. Lecavelier des, Lovis, C., Magrin, D., Malvasio, L., Marafatto, L., Michaelis, H., Munari, M., Olofsson, G., Ottacher, H., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piazza, D., Piotto, G., Pollacco, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Ribas, I., Rieder, M., Rohlfs, R., Safa, F., Salatti, M., Ségransan, D., Simon, A. E., Smith, A. M. S., Sordet, M., Steller, M., Thomas, N., Tschentscher, M., Van Eylen, V., Viotto, V., Walter, I., Walton, N. A., Wildi, F., Wolter, D., Bonfanti, A., Delrez, L., Hooton, M. J., Wilson, T. G., Fossati, L., Alibert, Y., Hoyer, S., Mustill, A. J., Osborn, H. P., Adibekyan, V., Gandolfi, D., Salmon, S., Sousa, S. G., Tuson, A., Van Grootel, V., Cabrera, J., Nascimbeni, V., Maxted, P. F. L., Barros, S. C. C., Billot, N., Bonfils, X., Borsato, L., Broeg, C., Davies, M. B., Deleuil, M., Demangeon, O. D. S., Fridlund, M., Lacedelli, G., Lendl, M., Persson, C., Santos, N. C., Scandariato, G., Szabó, Gy. M., Cameron, A. Collier, Udry, S., Benz, W., Beck, M., Ehrenreich, D., Fortier, A., Isaak, K. G., Queloz, D., Alonso, R., Asquier, J., Bandy, T., Bárczy, T., Barrado, D., Barragán, O., Baumjohann, W., Beck, T., Bekkelien, A., Bergomi, M., Busch, M-D., Brandeker, A., Cessa, V., Charnoz, S., Chazelas, B., Van Damme, C. Corral, Demory, B. -O., Erikson, A., Farinato, J., Futyan, D., Muñoz, A. Garcia, Gillon, M., Guedel, M., Guterman, P., Hasiba, J., Heng, K., Hernandez, E., Kiss, L., Kuntzer, T., Laskar, J., Etangs, A. Lecavelier des, Lovis, C., Magrin, D., Malvasio, L., Marafatto, L., Michaelis, H., Munari, M., Olofsson, G., Ottacher, H., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piazza, D., Piotto, G., Pollacco, D., Ragazzoni, R., Rando, N., Ratti, F., Rauer, H., Ribas, I., Rieder, M., Rohlfs, R., Safa, F., Salatti, M., Ségransan, D., Simon, A. E., Smith, A. M. S., Sordet, M., Steller, M., Thomas, N., Tschentscher, M., Van Eylen, V., Viotto, V., Walter, I., Walton, N. A., Wildi, F., and Wolter, D.

Abstract

The detection of a super-Earth and three mini-Neptunes transiting the bright ($V$ = 9.2 mag) star HD 108236 (also known as TOI-1233) was recently reported on the basis of TESS and ground-based light curves. We perform a first characterisation of the HD 108236 planetary system through high-precision CHEOPS photometry and improve the transit ephemerides and system parameters. We characterise the host star through spectroscopic analysis and derive the radius with the infrared flux method. We constrain the stellar mass and age by combining the results obtained from two sets of stellar evolutionary tracks. We analyse the available TESS light curves and one CHEOPS transit light curve for each known planet in the system. We find that HD 108236 is a Sun-like star with $R_{\star}=0.877\pm0.008 R_{\odot}$, $M_{\star}=0.869^{+0.050}_{-0.048} M_{\odot}$, and an age of $6.7_{-5.1}^{+4.0}$ Gyr. We report the serendipitous detection of an additional planet, HD 108236 f, in one of the CHEOPS light curves. For this planet, the combined analysis of the TESS and CHEOPS light curves leads to a tentative orbital period of about 29.5 days. From the light curve analysis, we obtain radii of $1.615\pm0.051$, $2.071\pm0.052$, $2.539_{-0.065}^{+0.062}$, $3.083\pm0.052$, and $2.017_{-0.057}^{+0.052}$ $R_{\oplus}$ for planets HD 108236 b to HD 108236 f, respectively. These values are in agreement with previous TESS-based estimates, but with an improved precision of about a factor of two. We perform a stability analysis of the system, concluding that the planetary orbits most likely have eccentricities smaller than 0.1. We also employ a planetary atmospheric evolution framework to constrain the masses of the five planets, concluding that HD 108236 b and HD 108236 c should have an Earth-like density, while the outer planets should host a low mean molecular weight envelope., Comment: 20 pages, 14 figures, accepted for publication by A&A

Published
2021
Full Text
View/download PDF

185. A compact system of small planets around a former red-giant star

Author

Charpinet, S., Fontaine, G., Brassard, P., Green, E.M., Van Grootel, V., Randall, S.K., Silvotti, R., Baran, A.S., Ostensen, R.H., Kawaler, S.D., and Telting, J.H.

Subjects
Orbits -- Observations, Extrasolar planets -- Observations, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Planets that orbit their parent star at less than about one astronomical unit (1 au is the Earth-Sun distance) are expected to be engulfed when the star becomes a red [...]

Published
2011

187. Six transiting planets and a chain of Laplace resonances in TOI-178

Author

Leleu, A., primary, Alibert, Y., additional, Hara, N. C., additional, Hooton, M. J., additional, Wilson, T. G., additional, Robutel, P., additional, Delisle, J.-B., additional, Laskar, J., additional, Hoyer, S., additional, Lovis, C., additional, Bryant, E. M., additional, Ducrot, E., additional, Cabrera, J., additional, Delrez, L., additional, Acton, J. S., additional, Adibekyan, V., additional, Allart, R., additional, Allende Prieto, C., additional, Alonso, R., additional, Alves, D., additional, Anderson, D. R., additional, Angerhausen, D., additional, Anglada Escudé, G., additional, Asquier, J., additional, Barrado, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Bayliss, D., additional, Beck, M., additional, Beck, T., additional, Bekkelien, A., additional, Benz, W., additional, Billot, N., additional, Bonfanti, A., additional, Bonfils, X., additional, Bouchy, F., additional, Bourrier, V., additional, Boué, G., additional, Brandeker, A., additional, Broeg, C., additional, Buder, M., additional, Burdanov, A., additional, Burleigh, M. R., additional, Bárczy, T., additional, Cameron, A. C., additional, Chamberlain, S., additional, Charnoz, S., additional, Cooke, B. F., additional, Corral Van Damme, C., additional, Correia, A. C. M., additional, Cristiani, S., additional, Damasso, M., additional, Davies, M. B., additional, Deleuil, M., additional, Demangeon, O. D. S., additional, Demory, B.-O., additional, Di Marcantonio, P., additional, Di Persio, G., additional, Dumusque, X., additional, Ehrenreich, D., additional, Erikson, A., additional, Figueira, P., additional, Fortier, A., additional, Fossati, L., additional, Fridlund, M., additional, Futyan, D., additional, Gandolfi, D., additional, García Muñoz, A., additional, Garcia, L. J., additional, Gill, S., additional, Gillen, E., additional, Gillon, M., additional, Goad, M. R., additional, González Hernández, J. I., additional, Guedel, M., additional, Günther, M. N., additional, Haldemann, J., additional, Henderson, B., additional, Heng, K., additional, Hogan, A. E., additional, Isaak, K., additional, Jehin, E., additional, Jenkins, J. S., additional, Jordán, A., additional, Kiss, L., additional, Kristiansen, M. H., additional, Lam, K., additional, Lavie, B., additional, Lecavelier des Etangs, A., additional, Lendl, M., additional, Lillo-Box, J., additional, Lo Curto, G., additional, Magrin, D., additional, Martins, C. J. A. P., additional, Maxted, P. F. L., additional, McCormac, J., additional, Mehner, A., additional, Micela, G., additional, Molaro, P., additional, Moyano, M., additional, Murray, C. A., additional, Nascimbeni, V., additional, Nunes, N. J., additional, Olofsson, G., additional, Osborn, H. P., additional, Oshagh, M., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Pedersen, P. P., additional, Pepe, F. A., additional, Persson, C. M., additional, Peter, G., additional, Piotto, G., additional, Polenta, G., additional, Pollacco, D., additional, Poretti, E., additional, Pozuelos, F. J., additional, Queloz, D., additional, Ragazzoni, R., additional, Rando, N., additional, Ratti, F., additional, Rauer, H., additional, Raynard, L., additional, Rebolo, R., additional, Reimers, C., additional, Ribas, I., additional, Santos, N. C., additional, Scandariato, G., additional, Schneider, J., additional, Sebastian, D., additional, Sestovic, M., additional, Simon, A. E., additional, Smith, A. M. S., additional, Sousa, S. G., additional, Sozzetti, A., additional, Steller, M., additional, Suárez Mascareño, A., additional, Szabó, Gy. M., additional, Ségransan, D., additional, Thomas, N., additional, Thompson, S., additional, Tilbrook, R. H., additional, Triaud, A., additional, Turner, O., additional, Udry, S., additional, Van Grootel, V., additional, Venus, H., additional, Verrecchia, F., additional, Vines, J. I., additional, Walton, N. A., additional, West, R. G., additional, Wheatley, P. J., additional, Wolter, D., additional, and Zapatero Osorio, M. R., additional

Published
2021
Full Text
View/download PDF

188. Gaia white dwarfs within 40 pc I : spectroscopic observations of new candidates

Author

Tremblay, P.-E., Hollands, M.A., Fusillo, N.P.G., McCleery, J., Izquierdo, P., Gänsicke, B.T., Cukanovaite, E., Koester, D., Brown, W.R., Charpinet, S., Cunningham, T., Farihi, J., Giammichele, N., van Grootel, V., Hermes, J.J., Hoskin, M.J., Jordan, S., Kepler, S.O., Kleinman, S.J., Manser, C.J., Marsh, T.R., de Martino, D., Nitta, A., Parsons, S.G., Pelisoli, I., Raddi, R., Rebassa-Mansergas, A., Ren, J.-J., Schreiber, M.R., Silvotti, R., Toloza, O., Toonen, S., and Torres, S.

Abstract

We present a spectroscopic survey of 230 white dwarf candidates within 40 pc of the Sun from the William Herschel Telescope and Gran Telescopio Canarias. All candidates were selected from Gaia Data Release 2 (DR2) and in almost all cases had no prior spectroscopic classifications. We find a total of 191 confirmed white dwarfs and 39 main-sequence star contaminants. The majority of stellar remnants in the sample are relatively cool (〈Teff〉 = 6200 K), showing either hydrogen Balmer lines or a featureless spectrum, corresponding to 89 DA and 76 DC white dwarfs, respectively. We also recover two DBA white dwarfs and 9–10 magnetic remnants. We find two carbon-bearing DQ stars and 14 new metal-rich white dwarfs. This includes the possible detection of the first ultra-cool white dwarf with metal lines. We describe three DZ stars for which we find at least four different metal species, including one which is strongly Fe- and Ni-rich, indicative of the accretion of a planetesimal with core-Earth composition. We find one extremely massive (1.31 ± 0.01 M⊙) DA white dwarf showing weak Balmer lines, possibly indicating stellar magnetism. Another white dwarf shows strong Balmer line emission but no infrared excess, suggesting a low-mass sub-stellar companion. High spectroscopic completeness (>99%) has now been reached for Gaia DR2 sources within 40 pc sample, in the northern hemisphere (δ > 0 deg) and located on the white dwarf cooling track in the Hertzsprung-Russell diagram. A statistical study of the full northern sample is presented in a companion paper.

Published
2020

189. TRAPPIST-1: Global Results of the Spitzer Exploration Science Program {\it Red Worlds}

Author

Ducrot, Elsa, Gillon, M., Delrez, L., Agol, E., Rimmer, P., Turbet, M., Günther, M. N., Demory, B-O., Triaud, A. H. M. J., Bolmont, E., Burgasser, A., Carey, S. J., Ingalls, J. G., Jehin, E., Leconte, J., Lederer, S. M., Queloz, D., Raymond, S. N., Selsis, F., Van Grootel, V., de Wit, J., Ducrot, Elsa, Gillon, M., Delrez, L., Agol, E., Rimmer, P., Turbet, M., Günther, M. N., Demory, B-O., Triaud, A. H. M. J., Bolmont, E., Burgasser, A., Carey, S. J., Ingalls, J. G., Jehin, E., Leconte, J., Lederer, S. M., Queloz, D., Raymond, S. N., Selsis, F., Van Grootel, V., and de Wit, J.

Abstract

With more than 1000 hours of observation from Feb 2016 to Oct 2019, the Spitzer Exploration Program Red Worlds (ID: 13067, 13175 and 14223) exclusively targeted TRAPPIST-1, a nearby (12pc) ultracool dwarf star orbited by seven transiting Earth-sized planets, all well-suited for a detailed atmospheric characterization with the upcoming JWST. In this paper, we present the global results of the project. We analyzed 88 new transits and combined them with 100 previously analyzed transits, for a total of 188 transits observed at 3.6 or 4.5 $\mu$m. We also analyzed 29 occultations (secondary eclipses) of planet b and eight occultations of planet c observed at 4.5 $\mu$m to constrain the brightness temperatures of their daysides. We identify several orphan transit-like structures in our Spitzer photometry, but all of them are of low significance. We do not confirm any new transiting planets. We estimate for TRAPPIST-1 transit depth measurements mean noise floors of $\sim$35 and 25 ppm in channels 1 and 2 of Spitzer/IRAC, respectively. most of this noise floor is of instrumental origins and due to the large inter-pixel inhomogeneity of IRAC InSb arrays, and that the much better interpixel homogeneity of JWST instruments should result in noise floors as low as 10ppm, which is low enough to enable the atmospheric characterization of the planets by transit transmission spectroscopy. We construct updated broadband transmission spectra for all seven planets which show consistent transit depths between the two Spitzer channels. We identify and model five distinct high energy flares in the whole dataset, and discuss our results in the context of habitability. Finally, we fail to detect occultation signals of planets b and c at 4.5 $\mu$m, and can only set 3$\sigma$ upper limits on their dayside brightness temperatures (611K for b 586K for c)., Comment: 50 pages, 21 figures. Accepted for publication in Astronomy and Astrophysics

Published
2020
Full Text
View/download PDF

190. $\textit{Gaia}$ white dwarfs within 40 pc I: spectroscopic observations of new candidates

Author

Tremblay, P. -E., Hollands, M. A., Fusillo, N. P. Gentile, McCleery, J., Izquierdo, P., Gänsicke, B. T., Cukanovaite, E., Koester, D., Brown, W. R., Charpinet, S., Cunningham, T., Farihi, J., Giammichele, N., van Grootel, V., Hermes, J. J., Hoskin, M. J., Jordan, S., Kepler, S. O., Kleinman, S. J., Manser, C. J., Marsh, T. R., de Martino, D., Nitta, A., Parsons, S. G., Pelisoli, I., Raddi, R., Rebassa-Mansergas, A., Ren, J. -J., Schreiber, M. R., Silvotti, R., Toloza, O., Toonen, S., Torres, S., Tremblay, P. -E., Hollands, M. A., Fusillo, N. P. Gentile, McCleery, J., Izquierdo, P., Gänsicke, B. T., Cukanovaite, E., Koester, D., Brown, W. R., Charpinet, S., Cunningham, T., Farihi, J., Giammichele, N., van Grootel, V., Hermes, J. J., Hoskin, M. J., Jordan, S., Kepler, S. O., Kleinman, S. J., Manser, C. J., Marsh, T. R., de Martino, D., Nitta, A., Parsons, S. G., Pelisoli, I., Raddi, R., Rebassa-Mansergas, A., Ren, J. -J., Schreiber, M. R., Silvotti, R., Toloza, O., Toonen, S., and Torres, S.

Abstract

We present a spectroscopic survey of 230 white dwarf candidates within 40 pc of the Sun from the William Herschel Telescope and Gran Telescopio Canarias. All candidates were selected from $\textit{Gaia}$ Data Release 2 (DR2) and in almost all cases had no prior spectroscopic classifications. We find a total of 191 confirmed white dwarfs and 39 main-sequence star contaminants. The majority of stellar remnants in the sample are relatively cool ($\langle T_{\rm eff} \rangle$ = 6200 K), showing either hydrogen Balmer lines or a featureless spectrum, corresponding to 89 DA and 76 DC white dwarfs, respectively. We also recover two DBA white dwarfs and 9--10 magnetic remnants. We find two carbon-bearing DQ stars and 14 new metal-rich white dwarfs. This includes the possible detection of the first ultra-cool white dwarf with metal lines. We describe three DZ stars for which we find at least four different metal species, including one which is strongly Fe- and Ni-rich, indicative of the accretion of a planetesimal with core-Earth composition. We find one extremely massive (1.31 $\pm$ 0.01 M$_{\odot}$) DA white dwarf showing weak Balmer lines, possibly indicating stellar magnetism. Another white dwarf shows strong Balmer line emission but no infrared excess, suggesting a low-mass sub-stellar companion. High spectroscopic completeness ($>$99%) has now been reached for $\textit{Gaia}$ DR2 sources within 40 pc sample, in the northern hemisphere ($\delta >$ 0 deg) and located on the white dwarf cooling track in the Hertzsprung-Russell diagram. A statistical study of the full northern sample is presented in a companion paper., Comment: 37 pages, 25 figures. Accepted for publication in MNRAS

Published
2020
Full Text
View/download PDF

191. Mitigating flicker noise in high-precision photometry. I -- Characterization of the noise structure, impact on the inferred transit parameters, and predictions for CHEOPS observations

Author

Sulis, S., Lendl, M., Hofmeister, S., Veronig, A., Fossati, L., Cubillos, P., Van Grootel, V., Sulis, S., Lendl, M., Hofmeister, S., Veronig, A., Fossati, L., Cubillos, P., and Van Grootel, V.

Abstract

In photometry, the short-timescale stellar variability ("flicker"), such as that caused by granulation and oscillations, can reach amplitudes comparable to the transit depth of Earth-sized planets and is correlated over the typical transit timescales. It can introduce systematic errors on the inferred planetary parameters when a small number of transits are observed. The objective of this paper is to characterize the statistical properties of this noise and quantify its impact on the inferred transit parameters. We used the extensive solar observations obtained with SoHO/VIRGO to characterize flicker noise. We simulated realistic transits across the solar disk using SDO/HMI data and used these to obtain transit light curves, which we used to estimate the errors made on the transit parameters. We make these light curves publicly available. To extend the study to a wider parameter range, we derived the properties of flicker noise using Kepler observations and studied their dependence on stellar parameters. Finally, we predicted the limiting stellar apparent magnitude for which the properties of the flicker noise can be extracted using high-precision CHEOPS and PLATO observations. Stellar granulation is a stochastic colored noise, and is stationary with respect to the stellar magnetic cycle. Both the flicker correlation timescales and amplitudes increase with the stellar mass and radius. If these correlations are not taken into account when fitting for the parameters of transiting exoplanets, this can bias the inferred parameters. In particular, we find errors of up to 10$\%$ on $R_p/R_s$ for an Earth-sized planet orbiting a Sun-like star. For F and G stars, flicker will significantly affect the inferred parameters of transits observed with CHEOPS and PLATO. Dedicated modeling strategies need to be developed to accurately characterize both the star and the transiting exoplanets., Comment: 20 pages, 24 figures, accepted for publication in Astronomy & Astrophysics

Published
2020
Full Text
View/download PDF

192. SPECULOOS -- Ultracool Dwarf Transit Survey: Target List and Strategy

Author

Sebastian, D., Gillon, M., Ducrot, E., Pozuelos, F. J., Garcia, L. J., Günther, M. N., Delrez, L., Queloz, D., Demory, B. O., Triaud, A. H. M. J., Burgasser, A., de Wit, J., Burdanov, A., Dransfield, G., Jehin, E., McCormac, J., Murray, C. A., Niraula, P., Pedersen, P. P., Rackham, B. V., Sohy, S., Thompson, S., Van Grootel, V., Sebastian, D., Gillon, M., Ducrot, E., Pozuelos, F. J., Garcia, L. J., Günther, M. N., Delrez, L., Queloz, D., Demory, B. O., Triaud, A. H. M. J., Burgasser, A., de Wit, J., Burdanov, A., Dransfield, G., Jehin, E., McCormac, J., Murray, C. A., Niraula, P., Pedersen, P. P., Rackham, B. V., Sohy, S., Thompson, S., and Van Grootel, V.

Abstract

One of the most promising avenues for the detailed study of temperate Earth-sized exoplanets is the detection of such planets in transit in front of stars small and nearby enough to make possible their thorough atmospheric characterisation with next generation telescopes like the James Webb Space telescope (JWST) or Extremely Large Telescope (ELT). In this context, the TRAPPIST-1 planets form an unique benchmark system that has gathered the interest of a large scientific community. The SPECULOOS survey is an exoplanet transit survey, that targets a volume-limited (40 pc) sample of ultracool dwarf stars. We define the SPECULOOS target list as the sum of three non-overlapping sub-programs incorporating the latest type objects (T_eff < 3000K): Program1: 365 dwarfs that are small and nearby enough to make possible the detailed atmospheric characterisation of an `Earth-like' planet with the upcoming JWST, Program2: 171 dwarfs of M5-type and later for which a significant detection of a planet similar to TRAPPIST-1b should be within reach of the exoplanet transit survey TESS, and Program3: 1121 dwarfs later than M6-type that aims to perform a statistical census of short-period planets around ultracool dwarf stars. Our compound target list includes 1657 photometrically classified late-type dwarfs. 260 of these targets are classified for the first time as possible nearby ultracool dwarf stars. Our general observational strategy is to monitor each target for 100 to 200hr with our telescope network, by efficiently using the synergy with TESS for our Program2 and a fraction of the targets of Program1. We expect to detect up to a few dozens temperate, rocky planets, a handful of them being amenable for atmospheric characterisation with JWST and other future giant telescopes which will improve drastically our understanding of the planetary population of the latest-type stars., Comment: Accepted for publication in A&A, 13pages, 10 figures

Published
2020
Full Text
View/download PDF

193. The hot dayside and asymmetric transit of WASP-189b seen by CHEOPS

Author

Lendl, M., Csizmadia, Sz., Deline, A., Fossati, L., Kitzmann, D., Heng, K., Hoyer, S., Salmon, S., Benz, W., Broeg, C., Ehrenreich, D., Fortier, A., Queloz, D., Bonfanti, A., Brandeker, A., Cameron, A. Collier, Delrez, L., Muñoz, A. Garcia, Hooton, M. J., Maxted, P. F. L., Morris, B. M., Van Grootel, V., Wilson, T. G., Alibert, Y., Alonso, R., Asquier, J., Bárczy, T. Bandy T., Barrado, D., Barros, S. C. C, Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Bergomi, M., Billot, N., Biondi, F., Bonfils, X., Bourrier, V., Busch, M-D., Cabrera, J., Cessa, V., Charnoz, S., Chazelas, B., Van Damme, C. Corral, Davies, M. B., Deleuil, M., Demangeon, O. D. S, Demory, B. -O., Erikson, A., Farinato, J., Fridlund, M., Futyan, D., Gandolfi, D., Gillon, M., Guterman, P., Hasiba, J., Hernandez, E., Isaak, K. G., Kiss, L., Kuntzer, T., Etangs, A. Lecavelier des, Lüftinger, T., Laskar, J., Lovis, C., Magrin, D., Malvasio, L., Marafatto, L., Michaelis, H., Munari, M., Nascimbeni, V., Olofsson, G., Ottacher, H., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piazza, D., Piotto, G., Pollacco, D., Ratti, F., Rauer, H., Ragazzoni, R., Rando, N., Ribas, I., Rieder, M., Rohlfs, R., Safa, F., Santos, N. C., Scandariato, G., Ségransan, D., Simon, A. E., Singh, V., Smith, A. M. S., Sordet, M., Sousa, S. G., Steller, M., Szabó, Gy. M., Thomas, N., Tschentscher, M., Udry, S., Viotto, V., Walter, I., Walton, N. A., Wildi, F., Wolter, D., Lendl, M., Csizmadia, Sz., Deline, A., Fossati, L., Kitzmann, D., Heng, K., Hoyer, S., Salmon, S., Benz, W., Broeg, C., Ehrenreich, D., Fortier, A., Queloz, D., Bonfanti, A., Brandeker, A., Cameron, A. Collier, Delrez, L., Muñoz, A. Garcia, Hooton, M. J., Maxted, P. F. L., Morris, B. M., Van Grootel, V., Wilson, T. G., Alibert, Y., Alonso, R., Asquier, J., Bárczy, T. Bandy T., Barrado, D., Barros, S. C. C, Baumjohann, W., Beck, M., Beck, T., Bekkelien, A., Bergomi, M., Billot, N., Biondi, F., Bonfils, X., Bourrier, V., Busch, M-D., Cabrera, J., Cessa, V., Charnoz, S., Chazelas, B., Van Damme, C. Corral, Davies, M. B., Deleuil, M., Demangeon, O. D. S, Demory, B. -O., Erikson, A., Farinato, J., Fridlund, M., Futyan, D., Gandolfi, D., Gillon, M., Guterman, P., Hasiba, J., Hernandez, E., Isaak, K. G., Kiss, L., Kuntzer, T., Etangs, A. Lecavelier des, Lüftinger, T., Laskar, J., Lovis, C., Magrin, D., Malvasio, L., Marafatto, L., Michaelis, H., Munari, M., Nascimbeni, V., Olofsson, G., Ottacher, H., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piazza, D., Piotto, G., Pollacco, D., Ratti, F., Rauer, H., Ragazzoni, R., Rando, N., Ribas, I., Rieder, M., Rohlfs, R., Safa, F., Santos, N. C., Scandariato, G., Ségransan, D., Simon, A. E., Singh, V., Smith, A. M. S., Sordet, M., Sousa, S. G., Steller, M., Szabó, Gy. M., Thomas, N., Tschentscher, M., Udry, S., Viotto, V., Walter, I., Walton, N. A., Wildi, F., and Wolter, D.

Abstract

The CHEOPS space mission dedicated to exoplanet follow-up was launched in December 2019, equipped with the capacity to perform photometric measurements at the 20 ppm level. As CHEOPS carries out its observations in a broad optical passband, it can provide insights into the reflected light from exoplanets and constrain the short-wavelength thermal emission for the hottest of planets by observing occultations and phase curves. Here, we report the first CHEOPS observation of an occultation, namely, that of the hot Jupiter WASP-189b, a $M_P \approx 2 M_J$ planet orbiting an A-type star. We detected the occultation of WASP-189 b at high significance in individual measurements and derived an occultation depth of $dF = 87.9 \pm 4.3$ppm based on four occultations. We compared these measurements to model predictions and we find that they are consistent with an unreflective atmosphere heated to a temperature of $3435 \pm 27$K, when assuming inefficient heat redistribution. Furthermore, we present two transits of WASP-189b observed by CHEOPS. These transits have an asymmetric shape that we attribute to gravity darkening of the host star caused by its high rotation rate. We used these measurements to refine the planetary parameters, finding a $\sim25\%$ deeper transit compared to the discovery paper and updating the radius of WASP-189b to $1.619\pm0.021 R_J$. We further measured the projected orbital obliquity to be $\lambda = 86.4^{+2.9}_{-4.4}$deg, a value that is in good agreement with a previous measurement from spectroscopic observations, and derived a true obliquity of $\Psi = 85.4\pm4.3$deg. Finally, we provide reference values for the photometric precision attained by the CHEOPS satellite: for the V=6.6 mag star, and using a one-hour binning, we obtain a residual RMS between 10 and 17ppm on the individual light curves, and 5.7ppm when combining the four visits., Comment: In press at Astronomy and Astrophysics

Published
2020
Full Text
View/download PDF

194. CHEOPS observations of the HD 108236 planetary system: a fifth planet, improved ephemerides, and planetary radii

Author

Bonfanti, A., primary, Delrez, L., additional, Hooton, M. J., additional, Wilson, T. G., additional, Fossati, L., additional, Alibert, Y., additional, Hoyer, S., additional, Mustill, A. J., additional, Osborn, H. P., additional, Adibekyan, V., additional, Gandolfi, D., additional, Salmon, S., additional, Sousa, S. G., additional, Tuson, A., additional, Van Grootel, V., additional, Cabrera, J., additional, Nascimbeni, V., additional, Maxted, P. F. L., additional, Barros, S. C. C., additional, Billot, N., additional, Bonfils, X., additional, Borsato, L., additional, Broeg, C., additional, Davies, M. B., additional, Deleuil, M., additional, Demangeon, O. D. S., additional, Fridlund, M., additional, Lacedelli, G., additional, Lendl, M., additional, Persson, C., additional, Santos, N. C., additional, Scandariato, G., additional, Szabó, Gy. M., additional, Collier Cameron, A., additional, Udry, S., additional, Benz, W., additional, Beck, M., additional, Ehrenreich, D., additional, Fortier, A., additional, Isaak, K. G., additional, Queloz, D., additional, Alonso, R., additional, Asquier, J., additional, Bandy, T., additional, Bárczy, T., additional, Barrado, D., additional, Barragán, O., additional, Baumjohann, W., additional, Beck, T., additional, Bekkelien, A., additional, Bergomi, M., additional, Brandeker, A., additional, Busch, M.-D., additional, Cessa, V., additional, Charnoz, S., additional, Chazelas, B., additional, Corral Van Damme, C., additional, Demory, B.-O., additional, Erikson, A., additional, Farinato, J., additional, Futyan, D., additional, Garcia Muñoz, A., additional, Gillon, M., additional, Guedel, M., additional, Guterman, P., additional, Hasiba, J., additional, Heng, K., additional, Hernandez, E., additional, Kiss, L., additional, Kuntzer, T., additional, Laskar, J., additional, Lecavelier des Etangs, A., additional, Lovis, C., additional, Magrin, D., additional, Malvasio, L., additional, Marafatto, L., additional, Michaelis, H., additional, Munari, M., additional, Olofsson, G., additional, Ottacher, H., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piazza, D., additional, Piotto, G., additional, Pollacco, D., additional, Ragazzoni, R., additional, Rando, N., additional, Ratti, F., additional, Rauer, H., additional, Ribas, I., additional, Rieder, M., additional, Rohlfs, R., additional, Safa, F., additional, Salatti, M., additional, Ségransan, D., additional, Simon, A. E., additional, Smith, A. M. S., additional, Sordet, M., additional, Steller, M., additional, Thomas, N., additional, Tschentscher, M., additional, Van Eylen, V., additional, Viotto, V., additional, Walter, I., additional, Walton, N. A., additional, Wildi, F., additional, and Wolter, D., additional

Published
2021
Full Text
View/download PDF

196. SPECULOOS: Ultracool dwarf transit survey

Author

Sebastian, D., primary, Gillon, M., additional, Ducrot, E., additional, Pozuelos, F. J., additional, Garcia, L. J., additional, Günther, M. N., additional, Delrez, L., additional, Queloz, D., additional, Demory, B. O., additional, Triaud, A. H. M. J., additional, Burgasser, A., additional, de Wit, J., additional, Burdanov, A., additional, Dransfield, G., additional, Jehin, E., additional, McCormac, J., additional, Murray, C. A., additional, Niraula, P., additional, Pedersen, P. P., additional, Rackham, B. V., additional, Sohy, S., additional, Thompson, S., additional, and Van Grootel, V., additional

Published
2021
Full Text
View/download PDF

197. HD 97658 and its super-Earth

Author

Van Grootel V., Gillon M., Valencia D., Madhusudhan N., Dragomir D., Howe A.R., and Burrows A.S.

Subjects
Physics, QC1-999
Abstract

Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition. We present the confirmation, based on Spitzer observations, that the super-Earth HD 97658 b transits its host star. HD 97658 is a low-mass (M* = 0.77 ± 0.05 M⊙) K1 dwarf, as determined from the Hipparcos parallax and stellar evolution modeling. To constrain the planet parameters, we carry out Bayesian global analyses of Keck-HIRES radial velocities, and MOST and Spitzer photometry. HD 97658 b is a massive (MP = 7.55−0.79+0.83 M⊕) and large (RP = 2.247−0.095+0.098 R⊕ at 4.5 μm super-Earth. We investigate the possible internal compositions for HD 97658 b. Our results indicate a large rocky component, by at least 60% by mass, and very little H-He components, at most 2% by mass. We also discuss how future asteroseismic observations can improve the knowledge of the HD 97658 system, in particular by constraining its age.

Published
2015
Full Text
View/download PDF

198. The CHEOPS mission

Author

Benz, W., primary, Broeg, C., additional, Fortier, A., additional, Rando, N., additional, Beck, T., additional, Beck, M., additional, Queloz, D., additional, Ehrenreich, D., additional, Maxted, P. F. L., additional, Isaak, K. G., additional, Billot, N., additional, Alibert, Y., additional, Alonso, R., additional, António, C., additional, Asquier, J., additional, Bandy, T., additional, Bárczy, T., additional, Barrado, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Bekkelien, A., additional, Bergomi, M., additional, Biondi, F., additional, Bonfils, X., additional, Borsato, L., additional, Brandeker, A., additional, Busch, M.-D., additional, Cabrera, J., additional, Cessa, V., additional, Charnoz, S., additional, Chazelas, B., additional, Collier Cameron, A., additional, Corral Van Damme, C., additional, Cortes, D., additional, Davies, M. B., additional, Deleuil, M., additional, Deline, A., additional, Delrez, L., additional, Demangeon, O., additional, Demory, B. O., additional, Erikson, A., additional, Farinato, J., additional, Fossati, L., additional, Fridlund, M., additional, Futyan, D., additional, Gandolfi, D., additional, Garcia Munoz, A., additional, Gillon, M., additional, Guterman, P., additional, Gutierrez, A., additional, Hasiba, J., additional, Heng, K., additional, Hernandez, E., additional, Hoyer, S., additional, Kiss, L. L., additional, Kovacs, Z., additional, Kuntzer, T., additional, Laskar, J., additional, Lecavelier des Etangs, A., additional, Lendl, M., additional, López, A., additional, Lora, I., additional, Lovis, C., additional, Lüftinger, T., additional, Magrin, D., additional, Malvasio, L., additional, Marafatto, L., additional, Michaelis, H., additional, de Miguel, D., additional, Modrego, D., additional, Munari, M., additional, Nascimbeni, V., additional, Olofsson, G., additional, Ottacher, H., additional, Ottensamer, R., additional, Pagano, I., additional, Palacios, R., additional, Pallé, E., additional, Peter, G., additional, Piazza, D., additional, Piotto, G., additional, Pizarro, A., additional, Pollaco, D., additional, Ragazzoni, R., additional, Ratti, F., additional, Rauer, H., additional, Ribas, I., additional, Rieder, M., additional, Rohlfs, R., additional, Safa, F., additional, Salatti, M., additional, Santos, N. C., additional, Scandariato, G., additional, Ségransan, D., additional, Simon, A. E., additional, Smith, A. M. S., additional, Sordet, M., additional, Sousa, S. G., additional, Steller, M., additional, Szabó, G. M., additional, Szoke, J., additional, Thomas, N., additional, Tschentscher, M., additional, Udry, S., additional, Van Grootel, V., additional, Viotto, V., additional, Walter, I., additional, Walton, N. A., additional, Wildi, F., additional, and Wolter, D., additional

Published
2020
Full Text
View/download PDF

199. The hot dayside and asymmetric transit of WASP-189 b seen by CHEOPS

Author

Lendl, M., primary, Csizmadia, Sz., additional, Deline, A., additional, Fossati, L., additional, Kitzmann, D., additional, Heng, K., additional, Hoyer, S., additional, Salmon, S., additional, Benz, W., additional, Broeg, C., additional, Ehrenreich, D., additional, Fortier, A., additional, Queloz, D., additional, Bonfanti, A., additional, Brandeker, A., additional, Collier Cameron, A., additional, Delrez, L., additional, Garcia Muñoz, A., additional, Hooton, M. J., additional, Maxted, P. F. L., additional, Morris, B. M., additional, Van Grootel, V., additional, Wilson, T. G., additional, Alibert, Y., additional, Alonso, R., additional, Asquier, J., additional, Bandy, T., additional, Bárczy, T., additional, Barrado, D., additional, Barros, S. C. C., additional, Baumjohann, W., additional, Beck, M., additional, Beck, T., additional, Bekkelien, A., additional, Bergomi, M., additional, Billot, N., additional, Biondi, F., additional, Bonfils, X., additional, Bourrier, V., additional, Busch, M.-D., additional, Cabrera, J., additional, Cessa, V., additional, Charnoz, S., additional, Chazelas, B., additional, Corral Van Damme, C., additional, Davies, M. B., additional, Deleuil, M., additional, Demangeon, O. D. S., additional, Demory, B.-O., additional, Erikson, A., additional, Farinato, J., additional, Fridlund, M., additional, Futyan, D., additional, Gandolfi, D., additional, Gillon, M., additional, Guterman, P., additional, Hasiba, J., additional, Hernandez, E., additional, Isaak, K. G., additional, Kiss, L., additional, Kuntzer, T., additional, Lecavelier des Etangs, A., additional, Lüftinger, T., additional, Laskar, J., additional, Lovis, C., additional, Magrin, D., additional, Malvasio, L., additional, Marafatto, L., additional, Michaelis, H., additional, Munari, M., additional, Nascimbeni, V., additional, Olofsson, G., additional, Ottacher, H., additional, Ottensamer, R., additional, Pagano, I., additional, Pallé, E., additional, Peter, G., additional, Piazza, D., additional, Piotto, G., additional, Pollacco, D., additional, Ratti, F., additional, Rauer, H., additional, Ragazzoni, R., additional, Rando, N., additional, Ribas, I., additional, Rieder, M., additional, Rohlfs, R., additional, Safa, F., additional, Santos, N. C., additional, Scandariato, G., additional, Ségransan, D., additional, Simon, A. E., additional, Singh, V., additional, Smith, A. M. S., additional, Sordet, M., additional, Sousa, S. G., additional, Steller, M., additional, Szabó, Gy. M., additional, Thomas, N., additional, Tschentscher, M., additional, Udry, S., additional, Viotto, V., additional, Walter, I., additional, Walton, N. A., additional, Wildi, F., additional, and Wolter, D., additional

Published
2020
Full Text
View/download PDF

200. TRAPPIST-1: Global results of the Spitzer Exploration Science Program Red Worlds

Author

Ducrot, E., primary, Gillon, M., additional, Delrez, L., additional, Agol, E., additional, Rimmer, P., additional, Turbet, M., additional, Günther, M. N., additional, Demory, B.-O., additional, Triaud, A. H. M. J., additional, Bolmont, E., additional, Burgasser, A., additional, Carey, S. J., additional, Ingalls, J. G., additional, Jehin, E., additional, Leconte, J., additional, Lederer, S. M., additional, Queloz, D., additional, Raymond, S. N., additional, Selsis, F., additional, Van Grootel, V., additional, and de Wit, J., additional

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results