Ground-based light curve follow-up validation observations of TESS object of interest 3616.01

NASA’s Transiting Exoplanet Survey Satellite (TESS) identified TOI-3616.01 as a candidate exoplanet based on periodic brightness dips consistent with a planetary transit. However, TESS detections can be affected by false positives from stellar variability, instrumental systematics, or nearby eclipsing binaries, requiring ground-based photometric follow-up for confirmation. The objective of this study was to obtain high-precision photometric observations of TOI-3616.01 during a predicted transit window to validate the transit signal and constrain its parameters, while also excluding nearby eclipsing binaries as potential contaminants. We conducted time-series photometry with George Mason University’s 0.8 m telescope using an R-band filter. Standard image calibrations and aperture photometry were applied, and systematic effects were mitigated through optimised detrending, removal of low-SNR frames, and exclusion of outliers. We further performed a nearby eclipsing binary (NEB) check using stars in the TESS aperture to rule out background contamination. Our follow-up observations detect a clear U-shaped transit signal consistent with the TESS-predicted ephemeris, with a transit depth of ~0.7% and duration matching expectations for a planetary origin. No significant variability was found in comparison stars or nearby sources, which strengthens the interpretation that the signal arises from TOI-3616.01 itself. These results support the planetary nature of the candidate and provide improved constraints on the system’s photometric parameters.