HIP 41378 observed by CHEOPS: Where is planet d?

Autor: 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., Navascues, D. Barrado, Barros, S. C., Baumjohann, W., Beck, T., Benz, W., Bergomi, M., Billot, N., Bonfanti, A., Broeg, C., Cameron, A. Collier, van Damme, C. Corral, 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., Korth, J., Lam, K. W. F., Laskar, J., Etangs, A. Lecavelier des, 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, M. Gy., Tuson, A., Udry, S., Ulmer-Moll, S., Van Grootel, V., Venturini, J., Villaver, E., Walton, N. A., Wilson, T. G., Wolter, D., Zingales, T.
Rok vydání: 2024
Předmět:
Zdroj: A&A 686, L18 (2024)
Druh dokumentu: Working Paper
DOI: 10.1051/0004-6361/202449689
Popis: 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, $P_\mathrm{d} = 278.36$ 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 $P_\mathrm{d}= 278.36$ d, but the observations show no transit. We find that large ($>22.4$ hours) 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 $P_\mathrm{d} \neq 278.36$ 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.
Comment: Accepted for publication in Astronomy and Astrophysics
Databáze: arXiv