TOI-3235 b : a transiting giant planet around an M4 dwarf star
Abstract
We present the discovery of TOI-3235 b, a short-period Jupiter orbiting an M dwarf with a stellar mass close to the critical mass at which stars transition from partially to fully convective. TOI-3235 b was first identified as a candidate from TESS photometry and confirmed with radial velocities from ESPRESSO and ground-based photometry from HATSouth, MEarth-South, TRAPPIST-South, LCOGT, and ExTrA. We find that the planet has a mass of 0.665 ± 0.025 MJ and a radius of 1.017 ± 0.044 RJ. It orbits close to its host star, with an orbital period of 2.5926 days but has an equilibrium temperature of ≈ 604 K, well below the expected threshold for radius inflation of hot Jupiters. The host star has a mass of 0.3939 ± 0.0030 M☉, a radius of 0.3697 ± 0.0018 R☉, an effective temperature of 3389 K, and a J-band magnitude of 11.706 ± 0.025. Current planet formation models do not predict the existence of gas giants such as TOI-3235 b around such low-mass stars. With a high transmission spectroscopy metric, TOI-3235 b is one of the best-suited giants orbiting M dwarfs for atmospheric characterization.
Citation
Hobson , M J , Jordán , A , Bryant , E M , Brahm , R , Bayliss , D , Hartman , J D , Bakos , G Á , Henning , T , Almenara , J M , Barkaoui , K , Benkhaldoun , Z , Bonfils , X , Bouchy , F , Charbonneau , D , Cointepas , M , Collins , K A , Eastman , J D , Ghachoui , M , Gillon , M , Goeke , R F , Horne , K , Irwin , J M , Jehin , E , Jenkins , J M , Latham , D W , Moldovan , D , Murgas , F , Pozuelos , F J , Ricker , G R , Schwarz , R P , Seager , S , Srdoc , G , Striegel , S , Timmermans , M , Vanderburg , A , Vanderspek , R & Winn , J N 2023 , ' TOI-3235 b : a transiting giant planet around an M4 dwarf star ' , Astrophysical Journal Letters , vol. 946 , no. 1 , L4 . https://doi.org/10.3847/2041-8213/acbd9a
Publication
Astrophysical Journal Letters
Status
Peer reviewed
ISSN
2041-8205Type
Journal article
Rights
Copyright © 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Description
Funding: A.J., R.B., and M.H. acknowledge support from ANID—Millennium Science Initiative—ICN12_009. A.J. acknowledges additional support from FONDECYT project 1210718. R.B. acknowledges support from FONDECYT Project 1120075 and from project IC120009 "Millennium Institute of Astrophysics (MAS)" of the Millennium Science Initiative. This work was funded by the Data Observatory Foundation. The MEarth Team gratefully acknowledges funding from the David and Lucile Packard Fellowship for Science and Engineering (awarded to D.C.). This material is based upon work supported by the National Science Foundation under grants AST-0807690, AST-1109468, AST-1004488 (Alan T. Waterman Award), and AST-1616624, and upon work supported by the National Aeronautics and Space Administration under grant No. 80NSSC18K0476 issued through the XRP Program. This work is made possible by a grant from the John Templeton Foundation. The opinions expressed in this publication are those of the authors and do not necessarily reflect the views of the John Templeton Foundation. The research leading to these results has received funding from the ARC grant for Concerted Research Actions, financed by the Wallonia-Brussels Federation. TRAPPIST is funded by the Belgian Fund for Scientific Research (Fond National de la Recherche Scientifique, FNRS) under the grant PDR T.0120.21. M.G. is F.R.S.-FNRS Research Director and E.J. is F.R.S.-FNRS Senior Research Associate. Observations were carried out from ESO La Silla Observatory. The postdoctoral fellowship of K.B. is funded by F.R.S.-FNRS grant T.0109.20 and by the Francqui Foundation.Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.