Warm Jupiters are close-in giant planets with relatively large planet-star separations (i.e., 10<a/R⋆<100). Given their weak tidal interactions with their host stars, measurements of stellar obliquity may be used to probe the initial obliquity distribution and dynamical history for close-in gas giants. Using spectroscopic observations, we confirm the planetary nature of TOI-1859b and determine the stellar obliquity of TOI-1859 to be λ=38.9−2.7+2.8deg relative to its planetary companion using the Rossiter-McLaughlin effect. TOI-1859b is a 64-day warm Jupiter orbiting around a late-F dwarf and has an orbital eccentricity of 0.57−0.16+0.12, inferred purely from transit light curves. The eccentric and misaligned orbit of TOI-1859b is likely an outcome of dynamical interactions, such as planet-planet scattering and planet-disk resonance crossing.
@article{arxiv.2305.16495,
title = {TOI-1859b: A 64-Day Warm Jupiter on an Eccentric and Misaligned Orbit},
author = {Jiayin Dong and Songhu Wang and Malena Rice and George Zhou and Chelsea X. Huang and Rebekah I. Dawson and Gudmundur K. Stefánsson and Samuel Halverson and Shubham Kanodia and Suvrath Mahadevan and Michael W. McElwain and Jaime A. Alvarado-Montes and Joe P. Ninan and Paul Robertson and Arpita Roy and Christian Schwab and Sarah E. Logsdon and Ryan C. Terrien and Karen A. Collins and Gregor Srdoc and Ramotholo Sefako and Didier Laloum and David W. Latham and Allyson Bieryla and Paul A. Dalba and Diana Dragomir and Steven Villanueva and Steve B. Howell and George R. Ricker and S. Seager and Joshua N. Winn and Jon M. Jenkins and Avi Shporer and David Rapetti},
journal= {arXiv preprint arXiv:2305.16495},
year = {2023}
}