J/A+A/686/L18 HIP 41378 velocity curve (Sulis+, 2024)
HIP 41378 observed by CHEOPS: where is planet d?
Sulis S., Borsato L., Grouffal S., Osborn H.P., Santerne A., Brandeker A.,
Guenther M.N., Heitzmann A., Lendl M., Fridlund M., Gandolfi D., Alibert Y.,
Alonso R., Barczy 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., Guedel M.,
Helling C., 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., Palle E., Peter G.,
Piazza D., Piotto G., Pollacco D., Queloz D., Ragazzoni R., Rando N.,
Rauer H., Ribas I., Santos N.C., Scandariato G., Segransan D., Simon A.E.,
Smith A.M.S., Sousa S.G., Stalport M., Steinberger M., Szabo 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.
<Astron. Astrophys. 686, L18 (2024)>
=2024A&A...686L..18S 2024A&A...686L..18S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Radial velocities
Keywords: planets and satellites: individual: HIP 41378
Abstract:
HIP 41378d is a long period planet that was observed to transit only
twice, three years apart, with K2. According to stability
considerations and a partial detection of the Rossiter-McLaughlin
effect, the literature assessed Pd=278.36d as the most likely
orbital period. We targeted HIP 41378d with CHEOPS at the predicted
transit timing based on Pd=278.36d, but the observations show no
transit. We find that large transit timing variations (TTV), larger
than 22.4-hours (duration related to the CHEOPS observation window)
could explain this non-detection. We also investigate the possibility
of an incorrect orbital solution, which would have major implications
for our knowledge of this system. If Pd!=278.36d, we find that the
periods minimizing the eccentricity are 101.22d and 371.14d. 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 is today 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.
Description:
CHEOPS observations of HIP 41378, predicted for Pd=278.36d and without
TTV.
Objects:
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RA (2000) DE Designation(s)
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08 26 27.84 +10 04 49.3 HIP 41378 = TIC 366443426
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
dataset.dat 41 1838 CHEOPS observations
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Byte-by-byte Description of file: dataset.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 --- Time Baricentric Julian date (BJD)
16- 23 F8.6 --- RFlux Relative flux before detrending
25- 32 F8.6 --- RFluxdet ?=- Relative after before detrending
34- 41 F8.6 --- e_RFlux Flux error
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Acknowledgements:
Sophia Sulis, sophia.sulis(at)lam.fr
(End) Patricia Vannier [CDS] 08-Apr-2024