Near-infrared imaging polarimetry of LkCa 15: A possible warped inner disk

Abstract

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, 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° 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.