| Abstract : | Subdwarf B stars are classified as core-helium burning stars and are located along the extreme horizontal branch in the Hertzsprung-Russell diagram. The formation of subdwarf B stars (sdB) is based upon a significant episode of mass loss occurring during their evolutionary phase on the red giant branch. These stars are commonly produced by the process of common-envelope ejection. These binary systems consist of a primary component known as sdB, accompanied by low mass main sequence companions as secondary components. TIC 165797593 is classified as an eclipsing binary system, characterised by a relatively short orbital period of 0.369822 days, which is equivalent to 8.87 hours. The reflection effect is distinguished by an amplitude that is approximately 33% of the amplitude of the entire light curve. The values of Teff and log(g) for the sdB star were derived as 28000K and 5.75, respectively, through implementation of stellar atmosphere models based on Local Thermodynamic Equilibrium (LTE) . Furthermore, the photometric parameters were obtained using the Tess data through the utilisation of the (Wilson–Devinney ) WD code. This facilitated the determination of the masses of the primary and secondary components, which were identified as M1 = 0.47 M☉ and M2 = 0.048 M☉, correspondingly. Moreover, the temperature of the secondary component was determined to be 2200K. Based on the mass and temperature of the secondary, it can be concluded that it is a brown dwarf with a mass 50 times that of Jupiter. This brown dwarf not only survived being engulfed by the red-giant envelope but also played a crucial role in initiating its ejection, which enabled the formation of the sdB star. Moreover, sdB belongs to the V1039 Her class of G-mode pulsators. Through pulsation studies, we have identified a total of 48 frequencies, with pulsating periods ranging from 0.25 to 3 hours.
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