Spectroscopic observations and space photometry of TIC 171084337, TIC 373414766 and TIC 450104319

The study of short-period binaries is essential for understanding the complex processes governing stellar evolution in tightly bound systems. In particular, near-contact binaries (NCBs) play a crucial role in our understanding of the formation and evolution of binary systems. Defined by Show in 1990, NCBs represent a specific subclass of close binaries where both components either fill or nearly fill their respective Roche lobes, leading to substantial proximity effects similar to those observed in W UMa-type systems, albeit without direct contact. These binaries exhibit strong tidal interaction and show EB-type light curve variations with asymmetrical profiles. Additionally, they often experience a decrease in the orbital period, likely due to mass transfer or angular momentum loss via magnetic braking. To fully understand all these behaviors, comprehensive photometric and spectroscopic analyses are essential. In this poster, we present preliminary results of the ground-based spectroscopic follow-up observations of three short-period binaries identified by the TESS satellite.