KELT-25 b and KELT-26 b: A Hot Jupiter and a Substellar Companion Transiting Young A Stars Observed by TESS

Martinez, Romy Rodriguez; Gaudi, B. Scott; Rodriguez, Joseph E.; Zhou, George; Labadie-Bartz, Jonathan; Quinn, Samuel N.; Penev, Kaloyan; Tan, Thiam-Guan; Latham, David W.; Paredes, Leonardo A.; Kielkopf, John F.; Addison, Brett; Wright, Duncan J.; Teske, Johanna; Howell, Steve B.; Ciardi, David; Ziegler, Carl; Stassun, Keivan G.; Johnson, Marshall C.; Eastman, Jason D.; Siverd, Robert J.; Beatty, Thomas G.; Bouma, Luke; Bedding, Timothy; Pepper, Joshua; Winn, Joshua; Lund, Michael B.; Villanueva, Steven, Jr.; Stevens, Daniel J.; Jensen, Eric L. N.; Kilby, Coleman; Crane, Jeffrey D.; Tokovinin, Andrei; Everett, Mark E.; Tinney, C. G.; Fausnaugh, Michael; Cohen, David H.; Bayliss, Daniel; Bieryla, Allyson; Cargile, Phillip A.; Collins, Karen A.; Conti, Dennis M.; Colon, Knicole D.; Curtis, Ivan A.; Depoy, D. L.; Evans, Phil; Feliz, Dax L.; Gregorio, Joao; Rothenberg, Jason; James, David J.; Joner, Michael D.; Kuhn, Rudolf B.; Manner, Mark; Khakpash, Somayeh; Marshall, Jennifer L.; McLeod, Kim K.; Penny, Matthew T.; Reed, Phillip A.; Relles, Howard M.; Stephens, Denise C.; Stockdale, Chris; Trueblood, Mark; Trueblood, Pat; Yao, Xinyu; Zambelli, Roberto; Vanderspek, Roland; Seager, Sara; Jenkins, Jon M.; Henry, Todd J.; James, Hodari-Sadiki; Jao, Wei-Chun; Wang, Sharon Xuesong; Butler, Paul; Thompson, Ian; Shectman, Stephen; Wittenmyer, Robert; Bowler, Brendan P.; Horner, Jonathan; Kane, Stephen R.; Mengel, Matthew W.; Morton, Timothy D.; Okumura, Jack; Plavchan, Peter; Zhang, Hui; Scott, Nicholas J.; Matson, Rachel A.; Mann, Andrew W.; Dragomir, Diana; Gunther, Max; Ting, Eric B.; Glidden, Ana; Quintana, Elisa, V
2020
ASTRONOMICAL JOURNAL
DOI
10.3847/1538-3881/ab9f2d
We present the discoveries of KELT-25 b (TIC 65412605, TOI-626.01) and KELT-26 b (TIC 160708862, TOI1337.01), 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 (T-eff = 8280(-180)(+440) K, M-star = 2.18(-0.11)(+0.12) M-circle dot), while KELT-26 b is on a 3.34 day orbit around the V = 9.95 star HD 134004 (T-eff = 8640(-240)(+500) K, M-circle dot = 1.93(-0.16)(+0.14) M-circle dot), 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 = 1.64(-0.043)(+0.039) R-J and a 3 sigma upper limit on the companion's mass of similar to 64 M-J. For KELT-26 b, we infer a planetary mass and radius of M-P = 1.41(-0.51)(+0.43) M-J and R-P = 1.94(-0.058)(+0.060) 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.