TOI-3235 b: A Transiting Giant Planet around an M4 Dwarf Star

DOI: 
10.3847/2041-8213/acbd9a
Publication date: 
13/03/2023
Main author: 
Hobson, Melissa J.
IAA authors: 
Pozuelos, Francisco J.
Authors: 
Hobson, Melissa J.;Jordán, Andrés;Bryant, E. M.;Brahm, R.;Bayliss, D.;Hartman, J. D.;Bakos, G. Á.;Henning, Th.;Almenara, Jose Manuel;Barkaoui, Khalid;Benkhaldoun, Zouhair;Bonfils, Xavier;Bouchy, François;Charbonneau, David;Cointepas, Marion;Collins, Karen A.;Eastman, Jason D.;Ghachoui, Mourad;Gillon, Michaël;Goeke, Robert F.;Horne, Keith;Irwin, Jonathan M.;Jehin, Emmanuel;Jenkins, Jon M.;Latham, David W.;Moldovan, Dan;Murgas, Felipe;Pozuelos, Francisco J.;Ricker, George R.;Schwarz, Richard P.;Seager, S.;Srdoc, Gregor;Striegel, Stephanie;Timmermans, Mathilde;Vanderburg, Andrew;Vanderspek, Roland;Winn, Joshua N.
Journal: 
The Astrophysical Journal
Publication type: 
Article
Volume: 
946
Pages: 
L4
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 M <SUB>J</SUB> and a radius of 1.017 ± 0.044 R <SUB>J</SUB>. 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 <SUB>⊙</SUB>, a radius of 0.3697 ± 0.0018 R <SUB>⊙</SUB>, 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.
Database: 
ADS
URL: 
https://ui.adsabs.harvard.edu/#abs/2023ApJ...946L...4H/abstract
ADS Bibcode: 
2023ApJ...946L...4H
Keywords: 
Exoplanets;Transit photometry;Radial velocity;M dwarf stars;498;1709;1332;982;Astrophysics - Earth and Planetary Astrophysics