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تسجيل مستخدم جديدNPOI Observations of the Exoplanet Host kappa Coronae Borealis and Their Implications for the Stars and Planets Masses and Ages
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We used the Navy Precision Optical Interferometer to measure the limb-darkened angular diameter of the exoplanet host star kappa CrB and obtained a value of 1.543 +/- 0.009 mas. We calculated its physical radius (5.06 +/- 0.04 R_Sun) and used photometric measurements from the literature with our diameter to determine kappa CrBs effective temperature (4788 +/- 17 K) and luminosity (12.13 +/- 0.09 L_Sun). We then placed the star on an H-R diagram to ascertain the stars age (3.42 +0.32/-0.25 Gyr) and mass (1.47 +/- 0.04 M_Sun) using a metallicity of [Fe/H] = +0.15. With this mass, we calculated the systems mass function with the orbital elements from a variety of sources, which produced a range of planetary masses: m_p sin i = 1.61 to 1.88 M_Jup. We also updated the extent of the habitable zone for the system using our new temperature.
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