KELT-25 b and KELT-26 b: A Hot Jupiter and a Substellar Companion Transiting Young A Stars Observed by TESS*
Romy Rodríguez Martínez, B. Scott Gaudi, Joseph E. Rodriguez, George Zhou, Jonathan Labadie-Bartz, Samuel N. Quinn, Kaloyan Penev, Thiam-Guan Tan, David W. Latham, Leonardo A. Paredes, John F. Kielkopf, Brett Addison, Duncan J. Wright, Johanna Teske, Steve B. Howell, David Ciardi, Carl Ziegler, Keivan G. Stassun, Marshall C. Johnson, Jason D. Eastman, Robert J. Siverd, Thomas G. Beatty, Luke Bouma, Timothy Bedding, Joshua Pepper, Joshua Winn, Michael B. Lund, Steven Villanueva, Daniel J. Stevens, Eric L. N. Jensen, Coleman Kilby, Jeffrey D. Crane, Andrei Tokovinin, Mark E. Everett, C. G. Tinney, Michael Fausnaugh, David H. Cohen, Daniel Bayliss, Allyson Bieryla, Phillip A. Cargile, Karen A. Collins, Dennis M. Conti, Knicole D. Colón, Ivan A. Curtis, D. L. Depoy, Phil Evans, Dax L. Feliz, Joao Gregorio, Jason Rothenberg, David J. James, Michael D. Joner, Rudolf B. Kuhn, Mark Manner, Somayeh Khakpash, Jennifer L. Marshall, Kim K. McLeod, Matthew T. Penny, Phillip A. Reed, Howard M. Relles, Denise C. Stephens, Chris Stockdale, Mark Trueblood, Pat Trueblood, Xinyu Yao, Roberto Zambelli, Roland Vanderspek, Sara Seager, Jon M. Jenkins, Todd J. Henry, Hodari-Sadiki James, Wei-Chun Jao, Sharon Xuesong Wang, Paul Butler, Ian Thompson, Stephen Shectman, Robert Wittenmyer, Brendan P. Bowler, Jonathan Horner, Stephen R. Kane, Matthew W. Mengel, Timothy D. Morton, Jack Okumura, Peter Plavchan, Hui Zhang, Nicholas J. Scott, Rachel A. Matson, Andrew W. Mann, Diana Dragomir, Max Günther, Eric B. Ting, Ana Glidden, Elisa V. Quintana
Abstract
Abstract We present the discoveries of KELT-25 b (TIC 65412605, TOI-626.01) and KELT-26 b (TIC 160708862, TOI-1337.01), two transiting companions orbiting relatively bright, early A stars. The transit signals were initially detected by the KELT survey and subsequently confirmed by Transiting Exoplanet Survey Satellite (TESS) photometry. KELT-25 b is on a 4.40 day orbit around the V = 9.66 star CD-24 5016 ( K, M ⋆ = M ⊙ ), while KELT-26 b is on a 3.34 day orbit around the V = 9.95 star HD 134004 ( = K, M ⋆ = M ⊙ ), which is likely an Am star. We have confirmed the substellar nature of both companions through detailed characterization of each system using ground-based and TESS photometry, radial velocity measurements, Doppler tomography, and high-resolution imaging. For KELT-25, we determine a companion radius of R P = R J and a 3 σ upper limit on the companion’s mass of ∼64 M J . For KELT-26 b, we infer a planetary mass and radius of M P = and R P = R J . From Doppler tomographic observations, we find KELT-26 b to reside in a highly misaligned orbit. This conclusion is weakly corroborated by a subtle asymmetry in the transit light curve from the TESS data. KELT-25 b appears to be in a well-aligned, prograde orbit, and the system is likely a member of the cluster Theia 449.