Further lunar occultations results from the Trebur Observatory, 2021–24

Abstract

Following up on our initial paper (Richichi and Ohlert, 2021), we report here on 60 lunar occultation events recorded between February 2021 and March 2024 at the Michael Adrian Observatorium. An improved version of the detector was employed for the present work. The program aims mainly at the direct measurement of the angular diameter of late-type stars, and the discovery or confirmation of binary stars with small separations. Among the results, we present first time angular diameter determinations for the late-type M giants IRC +20184 and BL Tau and for the bright carbon star TU Gem. Our diameter result for RX Cnc is the first determination outside the near-IR range. We also discovered or detected directly for the first time companions around SAO 79580, BL Tau again, and SAO 78643. The lunar occultation technique at our facility is capable to reach sources as faint as $\approx$ 10 V magnitude with an angular resolution at the milliarcsecond level.