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Register a new userSubaru/HiCIAO $HK_{rm s}$ imaging of LkH$alpha$ 330 - multi-band detection of the gap and spiral-like structures
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We present $H$- and $K_{rm s}$-bands observations of the LkH$alpha$ 330 disk with a multi-band detection of the large gap and spiral-like structures. The morphology of the outer disk ($rsim$$0farcs3$) at PA=0--45$^circ$ and PA=180--290$^circ$ are likely density wave-induced spirals and comparison between our observational results and simulations suggests a planet formation. We have also investigated the azimuthal profiles at the ring and the outer-disk regions as well as radial profiles in the directions of the spiral-like structures and semi-major axis. Azimuthal analysis shows a large variety in wavelength and implies that the disk has non-axisymmetric dust distributions. The radial profiles in the major-axis direction (PA=$271^circ$) suggest that the outer region ($rgeq0farcs25$) may be influenced by shadows of the inner region of the disk. The spiral-like directions (PA=10$^circ$ and 230$^circ$) show different radial profiles, which suggests that the surfaces of the spiral-like structures are highly flared and/or have different dust properties. Finally, a color-map of the disk shows a lack of an outer eastern region in the $H$-band disk, which may hint the presence of an inner object that casts a directional shadow onto the disk.
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