Five long-period TESS TOI RV and photometry

Initially identified by the Transiting Exoplanet Survey Satellite (TESS), we extensively monitored these targets with the Antarctic Search for Transiting Exoplanets (ASTEP), supported by other facilities in the TESS Follow-Up (TFOP) network. These targets occupy a relatively underexplored region of the period-radius parameter space, offering valuable primordial probes for planetary formation and migration as warm planets better maintain their evolutionary fingerprints.

To characterise these systems, we leverage high-resolution speckle imaging to search for nearby stellar companions, and refine stellar parameters using both reconnaissance spectroscopy and spectral energy distribution (SED) fitting. We combine TESS photometry with high- precision ground-based observations from ASTEP, and when available, include additional photometry and radial velocity data. We apply statistical validation to assess the planetary nature of each candidate and use allesfitter to jointly model the photometric and spectroscopic datasets with Markov Chain Monte Carlo (MCMC) sampling to derive robust posterior distributions.