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We are using precise radial velocities from CORALIE together with precision photometry from the Next Generation Transit Survey (NGTS) to follow-up stars with single-transit events detected with the Transiting Exoplanet Survey Satellite (TESS). As part of this survey, we identified a single transit on the star TIC-320687387, a bright (T  = 11.6) G-dwarf observed by TESS in Sectors 13 and 27. From subsequent monitoring of TIC-320687387 with CORALIE, NGTS, and Lesedi we determined that the companion, TIC-320687387 B, is a very low-mass star with a mass of |$96.2 \pm _{2.0}^{1.9}$|   M J and radius of |$1.14 \pm _{0.02}^{0.02}$|   R J placing it close to the hydrogen burning limit (∼80  M J). TIC-320687387 B is tidally decoupled and has an eccentric orbit, with a period of 29.77381 d and an eccentricity of 0.366 ± 0.003. Eclipsing systems such as TIC-320687387 AB allow us to test stellar evolution models for low-mass stars, which in turn are needed to calculate accurate masses and radii for exoplanets orbiting single low-mass stars. The sizeable orbital period of TIC-320687387 B makes it particularly valuable as its evolution can be assumed to be free from perturbations caused by tidal interactions with its G-type host star. [ABSTRACT FROM AUTHOR]

We report the results of a 60-h photometric campaign of a rapidly oscillating Ap star, J0855 (TYC 2488-1241-1). We have utilized the multi-site Las Cumbres Observatory's (LCO) 0.4-m telescopes to obtain short cadence B -band observations of an roAp star previously lacking detailed study. Our observations confirm the rotation period presented in the discovery paper of this star (P rot = 3.0918 d), and reveal the star to be pulsating in a distorted mode. The B data show this star to be among the highest amplitude roAp stars, with a peak-to-peak amplitude of 24 mmag. Modelling of the pulsation frequency at 197.2714 d−1 (2283  $$\mu$$ Hz; P = 7.30 min) shows that this star belongs to the subgroup of super-critical pulsators, where the observed frequencies are above the theoretical acoustic cutoff frequency. From the modelling, we deduce that the star's rotation axis is inclination angle of about 30° to the line of sight, with an angle of obliquity of the magnetic axis to the rotation axis of either 40° or 24° depending on whether the pulsation mode is dipole or quadrupole, respectively. [ABSTRACT FROM AUTHOR]