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EPIC 228735255b - An eccentric 6.57 day transiting hot Jupiter in Virgo

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 نشر من قبل Helen Giles
 تاريخ النشر 2017
  مجال البحث فيزياء
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We present the discovery of EPIC 228735255b, a P= 6.57 days Jupiter-mass (M$_P$=1.019$pm$0.070 M$_{Jup}$) planet transiting a V=12.5 (G5-spectral type) star in an eccentric orbit (e=$0.120^{+0.056}_{-0.046}$) detected using a combination of K2 photometry and ground-based observations. With a radius of 1.095$pm$0.018R$_{Jup}$ the planet has a bulk density of 0.726$pm$0.062$rho_{Jup}$. The host star has a [Fe/H] of 0.12$pm$0.045, and from the K2 light curve we find a rotation period for the star of 16.3$pm$0.1 days. This discovery is the 9th hot Jupiter from K2 and highlights K2s ability to detect transiting giant planets at periods slightly longer than traditional, ground-based surveys. This planet is slightly inflated, but much less than others with similar incident fluxes. These are of interest for investigating the inflation mechanism of hot Jupiters.



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