부산대학교 도서관

We present the discovery and characterization of two transiting planets observed by TESS in the light curves of the young and bright (V  = 9.67) star HD73583 (TOI-560). We perform an intensive spectroscopic and photometric space- and ground-based follow-up in order to confirm and characterize the system. We found that HD73583 is a young (∼500 Myr) active star with a rotational period of 12.08 ± 0.11  d, and a mass and radius of 0.73 ± 0.02 M⊙ and 0.65 ± 0.02 R⊙, respectively. HD 73583 b (Pb  = |$6.3980420 _{ - 0.0000062 } ^ { + 0.0000067 }$|  d) has a mass and radius of |$10.2 _{ - 3.1 } ^ { + 3.4 }$|   M ⊕ and 2.79 ± 0.10  R ⊕, respectively, which gives a density of |$2.58 _{ - 0.81 } ^ { + 0.95 }$|   |${\rm g\, cm^{-3}}$|⁠. HD 73583 c (Pc  =  |$18.87974 _{ - 0.00074 } ^ { + 0.00086 }$|  d) has a mass and radius of |$9.7 _{ - 1.7 } ^ { + 1.8 }$|   M ⊕ and |$2.39 _{ - 0.09 } ^ { + 0.10 }$|   R ⊕, respectively, which translates to a density of |$3.88 _{ - 0.80 } ^ { + 0.91 }$|   |${\rm g\, cm^{-3}}$|⁠. Both planets are consistent with worlds made of a solid core surrounded by a volatile envelope. Because of their youth and host star brightness, they both are excellent candidates to perform transmission spectroscopy studies. We expect ongoing atmospheric mass-loss for both planets caused by stellar irradiation. We estimate that the detection of evaporating signatures on H and He would be challenging, but doable with present and future instruments. [ABSTRACT FROM AUTHOR]