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تسجيل مستخدم جديدDiscovery of an Edge-on Debris Disk with a Dust Ring and an Outer Disk Wing-tilt Asymmetry
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Using VLT/SPHERE near-infrared dual-band imaging and integral field spectroscopy we discovered an edge-on debris disk around the 17,Myr old A-type member of the Scorpius-Centaurus OB association HD 110058. The edge-on disk can be traced to about 0.6 or 65 AU projected separation. In its northern and southern wings, the disk shows at all wavelengths two prominent, bright and symmetrically placed knots at 0.3 or 32 AU from the star. We interpret these knots as a ring of planetesimals whose collisions may produce most of the dust observed in the disk. We find no evidence for a bow in the disk, but we identify a pair of symmetric, hook-like features in both wings. Based on similar features in the Beta Pictoris disk we propose that this wing-tilt asymmetry traces either an outer planetesimal belt that is inclined with respect to the disk midplane or radiation-pressure-driven dust blown out from a yet unseen, inner belt which is inclined with respect to the disk midplane. The misaligned inner or outer disk may be a result of interaction with a yet unseen planet. Overall, the disk geometry resembles the nearby disk around Beta Pictoris, albeit seen at smaller radial scales.
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