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Description
We present the discoveries of KELT-25b (TIC 65412605, TOI-626.01) and KELT-26b (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-25b is on a 4.40day orbit around the V=9.66 star CD-245016 (Teff=8280_-180_^+440^K, M{star}=2.18_-0.11_^+0.12^M{sun}), while KELT-26b is on a 3.34day orbit around the V=9.95 star HD134004 (Teff=8640_-240_^+500^K, M{star}=1.93_-0.16_^+0.14^M{sun}), 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 RP=1.64_-0.043_^+0.039^RJ and a 3{sigma} upper limit on the companion's mass of ~64MJ. For KELT-26b, we infer a planetary mass and radius of MP=1.41_-0.51_^+0.43^M_J_ and RP=1.94_-0.058_^+0.060^RJ. From Doppler tomographic observations, we find KELT-26b 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-25b appears to be in a well-aligned, prograde orbit, and the system is likely a member of the cluster Theia449.
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