Spinning up a Daze: TESS Uncovers a Hot Jupiter orbiting the Rapid-Rotator TOI-778
Creators: name: Clark, Jake
name: Addison, Brett
name: Okumura, Jack
name: Vach, Sydney
name: Heitzmann, Alexis
name: Rodriguez, Joseph
name: Wright, Duncan
name: Clerte, Mathieu
name: Brown, Carolyn
name: Fetherolf, Tara
name: Wittenmyer, Robert
name: Plavchan, Peter
name: Kane, Stephen
name: Horner, Jonathan
name: Kielkopf, John
name: Shporer, Avi
name: Tinney, C.
name: Hui-Gen, Liu
name: Ballard, Sarah
name: Bowler, Brendan
name: Mengel, Matthew
name: Zhou, George
name: Lee, Annette
name: David, Avelyn
name: Heim, Jessica
name: Lee, Michele
name: Sevilla, Veronica
name: Zafar, Naqsh
name: Hinkel, Natalie
name: Allen, Bridgette
name: Bayliss, Daniel
name: Berberyan, Arthur
name: Berlind, Perry
name: Bieryla, Allyson
name: Bouchy, Francois
name: Brahm, Rafael
name: Bryant, Edward
name: Christiansen, Jessie
name: Ciardi, David
name: Ciardi, Krys
name: Collins, Karen
name: Dallant, Jules
name: Davis, Allen
name: Diaz, Matias
name: Dressing, Courtney
name: Esquerdo, Gilbert
name: Harre, Jan-Vincent
name: Howell, Steve
name: Jenkins, Jon
name: Jensen, Eric
name: Jones, Matias
name: Jordan, Andres
name: Latham, David
name: Lund, Michael
name: McCormac, James
name: Nielsen, Louise
name: Otegi, Jon
name: Quinn, Samuel
name: Radford, Don
name: Ricker, George
name: Schwarz, Richard
name: Seager, Sara
name: Smith, Alexis
name: Stockdale, Chris
name: Tan, Thiam-Guan
name: Udry, Stephane
name: Vanderspek, Roland
name: Gunther, Maximilian
name: Wang, Songhu
name: Wingham, Geof
name: Winn, Joshua
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: NASA's Transiting Exoplanet Survey Satellite (TESS) mission, has been uncovering a growing number of exoplanets orbiting nearby, bright stars. Most exoplanets that have been discovered by TESS orbit narrow-line, slow-rotating stars, facilitating the confirmation and mass determination of these worlds. We present the discovery of a hot Jupiter orbiting a rapidly rotating ($v\sin{(i)}= 35.1\pm1.0$km/s) early F3V-dwarf, HD115447 (TOI-778). The transit signal taken from Sectors 10 and 37 of TESS's initial detection of the exoplanet is combined with follow-up ground-based photometry and velocity measurements taken from Minerva-Australis, TRES, CORALIE and CHIRON to confirm and characterise TOI-778b. A joint analysis of the light curves and the radial velocity measurements yield a mass, radius, and orbital period for TOI-778b of $2.76^{+0.24}_{-0.23}$Mjup, $1.370\pm0.043$Rjup and $\sim4.63$ days, respectively. The planet orbits a bright ($V = 9.1$mag) F3-dwarf with $M=1.40\pm0.05$Msun, $R=1.70\pm0.05$Rsun, and $\log g=4.05\pm0.17$. We observed a spectroscopic transit of TOI-778b, which allowed us to derive a sky-projected spin-orbit angle of $18^{\circ}\pm11^{\circ}$, consistent with an aligned planetary system. This discovery demonstrates the capability of smaller aperture telescopes such as Minerva-Australis to detect the radial velocity signals produced by planets orbiting broad-line, rapidly rotating stars.
description: 18 pages, 9 figures, and 4 tables. Submitted to the Astronomical Journal