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تسجيل مستخدم جديدTESS Discovery of a Transiting Super-Earth in the $pi$ Mensae System
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We report the detection of a transiting planet around $pi$ Mensae (HD 39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The solar-type host star is unusually bright (V=5.7) and was already known to host a Jovian planet on a highly eccentric, 5.7-year orbit. The newly discovered planet has a size of $2.04pm 0.05$ $R_oplus$ and an orbital period of 6.27 days. Radial-velocity data from the HARPS and AAT/UCLES archives also displays a 6.27-day periodicity, confirming the existence of the planet and leading to a mass determination of $4.82pm 0.85$ $M_oplus$. The stars proximity and brightness will facilitate further investigations, such as atmospheric spectroscopy, asteroseismology, the Rossiter--McLaughlin effect, astrometry, and direct imaging.
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We report on the confirmation and mass determination of Pi Men c, the first transiting planet discovered by NASAs TESS space mission. Pi Men is a naked-eye (V=5.65 mag), quiet G0 V star that was previously known to host a sub-stellar companion (Pi Me
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ocity and transit, having only been measured for a handful of systems to-date. We aimed to place constraints on the orbital geometry of the outer planet in the $pi$ Mensae system, a G0V star at 18.3 pc host to a wide-orbit super-jovian ($Msin i = 10.02pm0.15$ $M_{rm Jup}$) with a 5.7-year period and an inner transiting super-earth ($M=4.82pm0.85$ $M_oplus$) with a 6.3-d period. We combined astrometric measurements from the Hipparcos and Gaia satellites with a precisely determined spectroscopic orbit in an attempt to constrain the inclination of the orbital plane of the outer planet. We measured an inclination of $i_b=49.9_{-4.5}^{+5.3}$ deg for the orbital plane of $pi$ Mensae b, leading to a direct measurement of its mass of $13.01_{-0.95}^{+1.03}$ $M_{rm Jup}$. We found a significant mutual inclination between the orbital planes of the two planets; a 95% credible interval for $i_{rm mut}$ of between $34.5^circ$ and $140.6^circ$ after accounting for the unknown position angle of the orbit of $pi$ Mensae c, strongly excluding a co-planar scenario for the two planets within this system. All orbits are stable in the present-day configuration, and secular oscillations of planet cs eccentricity are quenched by general relativistic precession. Planet c may have undergone high eccentricity tidal migration triggered by Kozai-Lidov cycles, but dynamical histories involving disk migration or in situ formation are not ruled out. Nonetheless, this system provides the first direct evidence that giant planets with large mutual inclinations have a role to play in the origins and evolution of some super-Earth systems.
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