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تسجيل مستخدم جديدA transiting warm giant planet around the young active star TOI-201
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We present the confirmation of the eccentric warm giant planet TOI-201 b, first identified as a candidate in textit{TESS} photometry (Sectors 1-8, 10-13, and 27-28) and confirmed using ground-based photometry from NGTS and radial velocities from FEROS, HARPS, CORALIE, and textsc{Minerva}-Australis. TOI-201 b orbits a young ($mathrm{0.87^{+0.46}_{-0.49} , Gyr}$) and bright(V=9.07 mag) F-type star with a $mathrm{52.9781 , d}$ period. The planet has a mass of $mathrm{0.42^{+0.05}_{-0.03}, M_J}$, a radius of $mathrm{1.008^{+0.012}_{-0.015}, R_J}$, and an orbital eccentricity of $0.28^{+0.06}_{-0.09}$; it appears to still be undergoing fairly rapid cooling, as expected given the youth of the host star. The star also shows long-term variability in both the radial velocities and several activity indicators, which we attribute to stellar activity. The discovery and characterization of warm giant planets such as TOI-201 b is important for constraining formation and evolution theories for giant planets.
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