Notes. The table lists, for each star: its name, radius in solar units (R_⋆), spectral type, and associated exoplanet (if any; a dash indicates no confirmed planet). The planetary semi-major axis a is given both in AU and in units of stellar radii (R_⊙). The average equatorial Alfvén surface radius (${\overline{AS}}_{\text{eq}}$) is reported in AU and in stellar radii. The following columns show the stellar X-ray surface luminosity (log L_X) and the ${\frac{S}{B}}_{\text{estimated}}$ range estimated from scaling laws; we only consider ${\frac{S}{B}}_{\text{estimated}}$ ranges for stars hosting at least one planet. All stellar parameters are taken from Chebly et al. (2023) and references therein, while X-ray luminosities are from the ROSAT All-Sky Survey unless noted otherwise. ^a From Acharya et al. (2023). ^b Estimated using the empirical relation of Pizzolato et al. (2003). ^c From Schmitt & Liefke (2004).