TS23/McDonald and FIES/NOT strike again. Two new warm Jupiter systems and outer companions in a third
Abstract
Warm Jupiters (gas giant planets with orbital periods of P∼8-200 d) are thought to be largely unaffected by the tidal interactions that can erase information about the dynamical histories of hot Jupiters. Their orbital eccentricities (e) and stellar obliquities are therefore expected to be preserved, making them valuable probes of giant-planet formation and migration. Our aim is to identify and characterise transiting warm Jupiters in order to expand the sample of well-characterised systems and enable further studies of giant-planet formation and migration. We analyse TESS transit photometry together with ground-based radial velocity measurements and perform a joint fit of the photometric and spectroscopic data from the TS23 and FIES spectrographs to determine the planetary and orbital parameters. We report on the discovery and characterisation of two new, transiting warm Jupiters; TOI-5120 b (Mp = 1.23±0.05 MJup, Rp = 0.969±0.017 RJup, P = 24.91645±0.00002 d, e = 0.10±0.02) and TOI-5699 b (Mp = 0.25±0.03 MJup, Rp = 0.996±0.015 RJup, P = 22.01850±0.00004 d, e = 0.30+0.09−0.08). We also refine the parameters of the known warm Jupiter TOI-2158 b (Mp = 0.87±0.04 MJup, Rp = 0.899±0.015 RJup, P = 8.60079+0.00002−0.00001 d, e = 0.028+0.013−0.014). In addition, we detect an outer planetary companion, TOI-2158 c (Mp sin i = 1.62±0.13 MJup, P = 414.5+1.5−1.6 d, e = 0.54±0.04), and identify a long-term radial velocity trend that may indicate another planetary companion on a wide orbit. The diverse architectures of these systems, in particular the presence and absence of outer companions, highlight the range of dynamical pathways leading to warm Jupiters.
Related
- Stellar companions sculpt hot Jupiter formation and spin-orbit evolution
- SOPHIE and TESS characterization of fourteen TESS objects of interest: Nine planetary systems and five low-mass stellar companions
- Tracing the Influence of Distant companions on Exoplanetary Systems (TIDES) I. Highly Eccentric and Misaligned Binary Companions to Hot Jupiters
- Transiting Planetary Systems with Distant Giant Companions Remain Moderately Coplanar
- Orbital Architecture of Super-Earth-Cold-Jupiter Systems from Transit Duration Ratios
BibTeX
@misc{knudstrup2026ts23mcdonald,
title = {{TS23/McDonald and FIES/NOT strike again. Two new warm Jupiter systems and outer companions in a third}},
author = {E. Knudstrup and D. Gandolfi and W. D. Cochran and M. Endl and P. MacQueen and T. Pugh and M. S. Lundkvist and C. M. Persson and A. Stokholm and M. L. Winther and J. R. Larsen and J. L. Rørsted and S. H. Albrecht and K. A. Collins and C. Watkins and B. Edwards and D. R. Ciardi and C. A. Clark and A. S. Polanski and C. Ziegler and C. Briceño and A. W. Mann and M. Everett and S. Howell and B. Safonov and T. Gan and K. Barkaoui and P. Benni and R. P. Schwarz and K. Horne and R. Sefako and D. Muthukrishna},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.30915},
eprint = {2609.30915},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.30915},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - TS23/McDonald and FIES/NOT strike again. Two new warm Jupiter systems and outer companions in a third
AU - E. Knudstrup
AU - D. Gandolfi
AU - W. D. Cochran
AU - M. Endl
AU - P. MacQueen
AU - T. Pugh
AU - M. S. Lundkvist
AU - C. M. Persson
AU - A. Stokholm
AU - M. L. Winther
AU - J. R. Larsen
AU - J. L. Rørsted
AU - S. H. Albrecht
AU - K. A. Collins
AU - C. Watkins
AU - B. Edwards
AU - D. R. Ciardi
AU - C. A. Clark
AU - A. S. Polanski
AU - C. Ziegler
AU - C. Briceño
AU - A. W. Mann
AU - M. Everett
AU - S. Howell
AU - B. Safonov
AU - T. Gan
AU - K. Barkaoui
AU - P. Benni
AU - R. P. Schwarz
AU - K. Horne
AU - R. Sefako
AU - D. Muthukrishna
PY - 2026
DA - 2026/09/25
PB - arXiv
DO - 10.48550/arxiv.2609.30915
UR - https://arxiv.org/abs/2609.30915
AB - Warm Jupiters (gas giant planets with orbital periods of P∼8-200 d) are thought to be largely unaffected by the tidal interactions that can erase information about the dynamical histories of hot Jupiters. Their orbital eccentricities (e) and stellar obliquities are therefore expected to be preserved, making them valuable probes of giant-planet formation and migration. Our aim is to identify and characterise transiting warm Jupiters in order to expand the sample of well-characterised systems and enable further studies of giant-planet formation and migration. We analyse TESS transit photometry together with ground-based radial velocity measurements and perform a joint fit of the photometric and spectroscopic data from the TS23 and FIES spectrographs to determine the planetary and orbital parameters. We report on the discovery and characterisation of two new, transiting warm Jupiters; TOI-5120 b (M_p = 1.23±0.05 M_Jup, R_p = 0.969±0.017 R_Jup, P = 24.91645±0.00002 d, e = 0.10±0.02) and TOI-5699 b (M_p = 0.25±0.03 M_Jup, R_p = 0.996±0.015 R_Jup, P = 22.01850±0.00004 d, e = 0.30^+0.09_−0.08). We also refine the parameters of the known warm Jupiter TOI-2158 b (M_p = 0.87±0.04 M_Jup, R_p = 0.899±0.015 R_Jup, P = 8.60079^+0.00002_−0.00001 d, e = 0.028^+0.013_−0.014). In addition, we detect an outer planetary companion, TOI-2158 c (M_p sin i = 1.62±0.13 M_Jup, P = 414.5^+1.5_−1.6 d, e = 0.54±0.04), and identify a long-term radial velocity trend that may indicate another planetary companion on a wide orbit. The diverse architectures of these systems, in particular the presence and absence of outer companions, highlight the range of dynamical pathways leading to warm Jupiters.
ER -