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تسجيل مستخدم جديدGravity-Darkening Analysis of Misaligned Hot Jupiter MASCARA-4 b
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MASCARA-4 b is a hot Jupiter in a highly-misaligned orbit around a rapidly-rotating A3V star that was observed for 54 days by the Transiting Exoplanet Survey Satellite (tess). We perform two analyses of MASCARA-4 b using a stellar gravity-darkened model. First, we measure MASCARA-4 bs misaligned orbital configuration by modeling its tess~photometric light curve. We take advantage of the asymmetry in MASCARA-4 bs transit due to its host stars gravity-darkened surface to measure MASCARA-4 bs true spin-orbit angle to be $104^{circ+7^circ}_{-13^circ}$. We also detect a $sim4sigma$ secondary eclipse at $0.491pm0.007$ orbital phase, proving that the orbit is slightly eccentric. Second, we model MASCARA-4 bs insolation including gravity-darkening and find that the planets received XUV flux varies by $4$% throughout its orbit. MASCARA-4 bs short-period, polar orbit suggests that the planet likely underwent dramatic orbital evolution to end up in its present-day configuration and that it receives a varying stellar irradiance that perpetually forces the planet out of thermal equilibrium. These findings make MASCARA-4 b an excellent target for follow-up characterization to better understand orbital evolution and current-day of planets around high-mass stars.
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