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44 Validated Planets from K2 Campaign 10

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 نشر من قبل John Livingston
 تاريخ النشر 2018
  مجال البحث فيزياء
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We present 44 validated planets from the 10$^mathrm{th}$ observing campaign of the NASA $K2$ mission, as well as high resolution spectroscopy and speckle imaging follow-up observations. These 44 planets come from an initial set of 72 vetted candidates, which we subjected to a validation process incorporating pixel-level analyses, light curve analyses, observational constraints, and statistical false positive probabilities. Our validated planet sample has median values of $R_p$ = 2.2 $R_oplus$, $P_mathrm{orb}$ = 6.9 days, $T_{mathrm{eq}}$ = 890 K, and $J$ = 11.2 mag. Of particular interest are four ultra-short period planets ($P_mathrm{orb} lesssim 1$ day), 16 planets smaller than 2 $R_oplus$, and two planets with large predicted amplitude atmospheric transmission features orbiting infrared-bright stars. We also present 27 planet candidates, most of which are likely to be real and worthy of further observations. Our validated planet sample includes 24 new discoveries, and has enhanced the number of currently known super-Earths ($R_p approx 1-2 R_oplus$), sub-Neptunes ($R_p approx 2-4 R_oplus$), and sub-Saturns ($R_p approx 4-8 R_oplus$) orbiting bright stars ($J = 8-10$ mag) by $sim$4%, $sim$17%, and $sim$11%, respectively.



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