Presentation #102.214 in the session Poster Session.
The Adams Observatory at Austin College provides ground-based photometric support for NASA’s Transiting Exoplanet Survey Satellite (TESS) mission through the TESS Follow-up Observing Program Sub Group 1 (TFOP SG1). The main telescope at the Adams Observatory is a 0.61-m f/8 DFM telescope of Ritchey-Chrétien design. When coupled with a Finger Lakes Instruments (FLI) Proline 16803 imager, this system produces a 26’ x 26’ field of view and 0.38” pixel scale. Under optimal conditions, we can detect a minimum transit depth of ~3.0 ppt, which for an M-dwarf star would correspond to an exoplanet with radius ~3 Earth radii.
Here we summarize the Adams Observatory follow-up observations for 2018-2022. Our high-precision observations offer four possible cases for TESS targets: 1) light curve from the target star indicating a possible transiting exoplanet, 2) light curve from a nearby star indicating a nearby eclipsing binary (NEB) star system, 3) flat light curves for both the target star and nearby stars, and 4) inconclusive results. Over the past four years, 46% of our observations show a transit on the target star (Case 1), and these targets have been elevated to verified planetary candidate status. Another 10% of the observations show a transit on a nearby star with a possible NEB (Case 2). Roughly 36% of the observations exhibit flat light curves (Case 3), which could indicate that the planet is too small for detection at the Adams Observatory, the predicted transit timing is off, or the TESS observation is a false positive. Due to their flat light curves, some Case 3 nearby stars are cleared of NEBs. Finally, 8% of our observations are inconclusive (Case 4) due to relatively high noise in the data. We plan to continue follow-up observations during the TESS Extended Missions.