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A long period (P = 61.8-d) M5V dwarf eclipsing a Sun-like star from TESS and NGTS

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 نشر من قبل Samuel Gill Dr
 تاريخ النشر 2020
  مجال البحث فيزياء
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The Transiting Exoplanet Survey Satellite (TESS) has produced a large number of single transit event candidates which are being monitored by the Next Generation Transit Survey (NGTS). We observed a second epoch for the TIC-231005575 system (Tmag = 12.06, Teff = 5500 +- 85 K) with NGTS and a third epoch with Las Cumbres Observatorys (LCO) telescope in South Africa to constrain the orbital period (P = 61.777 d). Subsequent radial velocity measurements with CORALIE revealed the transiting object has a mass of M2 = 0.128 +- 0.003 M$_odot$, indicating the system is a G-M binary. The radius of the secondary is R2 = 0.154 +- 0.008 R$_odot$ and is consistent with models of stellar evolution to better than 1-$sigma$.



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