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.
planets and satellites: detection
techniques: radial velocities
techniques: photometric
stars: individual: TOI-1789-planetary system
Author
Akanksha Khandelwal
Physical Research Laboratory
Indian Institute of Technology
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
Leiden University
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
A. Hatzes
Thüringer Landessternwarte Tautenburg
Neelam J.S.S.V. Prasad
Physical Research Laboratory
Massimiliano Esposito
Thüringer Landessternwarte Tautenburg
Sireesha Chamarthi
Thüringer Landessternwarte Tautenburg
German Aerospace Center (DLR)
Ashirbad Nayak
Physical Research Laboratory
D. Dishendra
Physical Research Laboratory
Steve B. Howell
NASA Ames Research Center
Monthly Notices of the Royal Astronomical Society
0035-8711 (ISSN) 1365-2966 (eISSN)
Vol. 509 3 3339-3354Subject Categories
Evolutionary Biology
Astronomy, Astrophysics and Cosmology
Zoology
DOI
10.1093/mnras/stab2970