AstraLux-TESS planet candidates

Among the 185 planet host candidate stars observed, we found 13 (7%) to be accompanied by additional sources within 2.2 arcsec separation. Among them, six are not associated to sources in the Gaia DR3 catalog, thus contaminating the TESS light curve. Even if no contaminants are detected, we can provide upper limits and probabilities to the possible existence of field contaminants through the sensitivity limits of our images.

Among the isolated hosts, we can discard hazardous companions (bright enough to mimic a planetary transit signals) with an accuracy below 1% for all their planets. The results from this catalog are key for the statistical validation of small planets (prime targets of the TESS mission) and planets around intermediate-mass stars in the main-sequence. These two populations of planets are hard to confirm with the radial velocity technique because of the shallow amplitude of small planets and the high-rotational velocities and low number of available spectral lines in the intermediate stellar mass regime.

Our results also demonstrate the importance of this type of follow-up observations for future transit missions like PLATO, even in the Gaia era.