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Near-Infrared Imaging Polarimetry of LkCa 15: A Possible Warped Inner Disk

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 نشر من قبل Daehyeon Oh
 تاريخ النشر 2016
  مجال البحث فيزياء
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We present high-contrast H-band polarized intensity images of the transitional disk around the young solar-like star LkCa 15. By utilizing Subaru/HiCIAO for polarimetric differential imaging, both the angular resolution and the inner working angle reach 0.07 and r=0.1, respectively. We obtained a clearly resolved gap (width <~ 27 AU) at ~ 48 AU from the central star. This gap is consistent with images reported in previous studies. We also confirmed the existence of a bright inner disk with a misaligned position angle of 13+/-4 degree with respect to that of the outer disk, i.e., the inner disk is possibly warped. The large gap and the warped inner disk both point to the existence of a multiple planetary system with a mass of <~1Mjup.

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