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Evidence of Different Formation Mechanisms for Hot versus Warm Super-Earths

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 نشر من قبل Wei Zhu
 تاريخ النشر 2015
  مجال البحث فيزياء
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 تأليف Wei Zhu




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Using the Kepler planet sample from Buchhave et al. and the statistical method clarified by Schlaufman, I show that the shorter-period super-Earths have a different dependence on the host star metallicity from the longer-period super-Earths, with the transition period being in the period range from 70 to 100 days. The hosts of shorter-period super-Earths are on average more metal-rich than those of longer-period super-Earths. The existence of such a transition period cannot be explained by any single theory of super-Earth formation, suggesting that super-Earths have formed via at least two mechanisms.



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