Discovery of an inflated hot Jupiter around a slightly evolved star TOI-1789
Journal article, 2022
We report here the discovery of a hot Jupiter at an orbital period of 3.208664 ± 0.000015 d around TOI-1789 (TYC 1962-00303-1, TESSmag = 9.1) based on the TESS photometry, ground-based photometry, and high-precision radial velocity (RV) observations. The high-precision RV observations were obtained from the high-resolution spectrographs, PARAS at Physical Research Laboratory (PRL), India, and TCES at Thüringer Landessternwarte Tautenburg (TLS), Germany, and the ground-based transit observations were obtained using the 0.43-m telescope at PRL with the Bessel-R filter. The host star is a slightly evolved (log g∗ = 3.943+0.023-0.043), late F-type (Teff= 5991 ± 55 K), metal-rich star ([Fe/H] = 0.373+0.071-0.086 dex) with a radius of R ∗ = 2.168+0.036}-0.034 R located at a distance of 223.53+0.91-0.90} pc. The simultaneous fitting of the multiple light curves and the RV data of TOI-1789 reveals that TOI-1789 b has a mass of MP = 0.70 ± 0.16 MJ, a radius of RP = 1.44+0.24-0.14, RJ, and a bulk density of ρP = 0.28+0.14-0.12 g cm-3 with an orbital separation of a = 0.04882+0.00063-0.0016 au. This puts TOI-1789 b in the category of inflated hot Jupiters. It is one of the few nearby evolved stars with a close-in planet. The detection of such systems will contribute to our understanding of mechanisms responsible for inflation in hot Jupiters and also provide an opportunity to understand the evolution of planets around stars leaving the main-sequence branch.
stars: individual: TOI-1789-planetary system
techniques: photometric
planets and satellites: detection
techniques: radial velocities
Author
Akanksha Khandelwal
Indian Institute of Technology
Physical Research Laboratory
Priyanka Chaturvedi
Thüringer Landessternwarte Tautenburg
Abhijit Chakraborty
Physical Research Laboratory
Rishikesh Sharma
Physical Research Laboratory
Eike W. Guenther
Thüringer Landessternwarte Tautenburg
Carina Persson
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Malcolm Fridlund
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Leiden University
A. Hatzes
Thüringer Landessternwarte Tautenburg
Neelam J.S.S.V. Prasad
Physical Research Laboratory
Massimiliano Esposito
Thüringer Landessternwarte Tautenburg
Sireesha Chamarthi
German Aerospace Center (DLR)
Thüringer Landessternwarte Tautenburg
Ashirbad Nayak
Physical Research Laboratory
D. Dishendra
Physical Research Laboratory
Steve B. Howell
National Aeronautics and Space Administration (NASA)
Monthly Notices of the Royal Astronomical Society
0035-8711 (ISSN) 1365-2966 (eISSN)
Vol. 509 3 3339-3354Subject Categories (SSIF 2011)
Evolutionary Biology
Astronomy, Astrophysics and Cosmology
Zoology
DOI
10.1093/mnras/stab2970