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 (Teff=8280-180+440 K, M ∗ = 2.18-0.11+0.12 M o˙), while KELT-26 b is on a 3.34 day orbit around the V = 9.95 star HD 134004 (Teff = 8640-240+500 K, M ∗ = 1.93-0.16+0.14 M o˙), 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 3σ 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 = 1.41-0.51+0.43MJ 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.
Publication Source (Journal or Book title)
Martínez, R., Gaudi, B., Rodriguez, J., Zhou, G., Labadie-Bartz, J., Quinn, S., Penev, K., Tan, T., Latham, D., Paredes, L., Kielkopf, J., Addison, B., Wright, D., Teske, J., Howell, S., Ciardi, D., Ziegler, C., Stassun, K., Johnson, M., Eastman, J., Siverd, R., Beatty, T., Bouma, L., Bedding, T., Pepper, J., Winn, J., Lund, M., Villanueva, S., Stevens, D., Jensen, E., Kilby, C., Crane, J., & Tokovinin, A. (2020). KELT-25 b and KELT-26 b: A Hot Jupiter and a Substellar Companion Transiting Young A Stars Observed by TESS. Astronomical Journal, 160 (3) https://doi.org/10.3847/1538-3881/ab9f2d