Bibcode
Sulis, S.; Borsato, L.; Grouffal, S.; Osborn, H. P.; Santerne, A.; Brandeker, A.; Günther, M. N.; Heitzmann, A.; Lendl, M.; Fridlund, M.; Gandolfi, D.; Alibert, Y.; Alonso, R.; Bárczy, T.; Barrado Navascues, D.; Barros, S. C. C.; Baumjohann, W.; Beck, T.; Benz, W.; Bergomi, M.; Billot, N.; Bonfanti, A.; Broeg, C.; Collier Cameron, A.; Corral van Damme, C.; Correia, A. C. M.; Csizmadia, Sz.; Cubillos, P. E.; Davies, M. B.; Deleuil, M.; Deline, A.; Delrez, L.; Demangeon, O. D. S.; Demory, B. -O.; Derekas, A.; Edwards, B.; Ehrenreich, D.; Erikson, A.; Fortier, A.; Fossati, L.; Gazeas, K.; Gillon, M.; Güdel, M.; Helling, Ch.; Hoyer, S.; Isaak, K. G.; Kiss, L. L.; Korth, J.; Lam, K. W. F.; Laskar, J.; Lecavelier des Etangs, A.; Magrin, D.; Maxted, P. F. L.; Mordasini, C.; Nascimbeni, V.; Olofsson, G.; Ottensamer, R.; Pagano, I.; Pallé, E.; Peter, G.; Piazza, D.; Piotto, G.; Pollacco, D.; Queloz, D.; Ragazzoni, R.; Rando, N.; Rauer, H.; Ribas, I.; Santos, N. C.; Scandariato, G.; Ségransan, D.; Simon, A. E.; Smith, A. M. S.; Sousa, S. G.; Stalport, M.; Steinberger, M.; Szabó, Gy. M.; Tuson, A.; Udry, S.; Ulmer-Moll, S.; Van Grootel, V.; Venturini, J.; Villaver, E.; Walton, N. A.; Wilson, T. G.; Wolter, D.; Zingales, T.
Bibliographical reference
Astronomy and Astrophysics
Advertised on:
6
2024
Journal
Citations
0
Refereed citations
0
Description
HIP 41378 d is a long-period planet that has only been observed to transit twice, three years apart, with K2. According to stability considerations and a partial detection of the Rossiter-McLaughlin effect, Pd = 278.36 d has been determined to be the most likely orbital period. We targeted HIP 41378 d with CHEOPS at the predicted transit timing based on Pd = 278.36 d, but the observations show no transit. We find that large (> 22.4 h) transit timing variations (TTVs) could explain this non-detection during the CHEOPS observation window. We also investigated the possibility of an incorrect orbital solution, which would have major implications for our knowledge of this system. If Pd ≠ 278.36 d, the periods that minimize the eccentricity would be 101.22 d and 371.14 d. The shortest orbital period will be tested by TESS, which will observe HIP 41378 in Sector 88 starting in January 2025. Our study shows the importance of a mission like CHEOPS, which today is the only mission able to make long observations (i.e., from space) to track the ephemeris of long-period planets possibly affected by large TTVs.
The raw and detrended photometric time-series data are available at the CDS via anonymous ftp to cdsarc.cds.unistra.fr (ftp://130.79.128.5) or via https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/686/L18
The CHEOPS program ID is CH_PR110048.