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تسجيل مستخدم جديدFirst Images of the Protoplanetary Disk Around PDS 201
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Scattered light imaging has revealed nearly a dozen circumstellar disks around young Herbig Ae/Be stars$-$enabling studies of structures in the upper disk layers as potential signs of on-going planet formation. We present the first images of the disk around the variable Herbig Ae star PDS 201 (V* V351 Ori), and an analysis of the images and spectral energy distribution through 3D Monte-Carlo radiative transfer simulations and forward modelling. The disk is detected in three datasets with LBTI/LMIRCam at the LBT, including direct observations in the $Ks$ and $L$ filters, and an $L$ observation with the 360$^circ$ vector apodizing phase plate coronagraph. The scattered light disk extends to a very large radius of $sim$250 au, which places it among the largest of such disks. Exterior to the disk, we establish detection limits on substellar companions down to $sim$5 M$_{Jup}$ at $gtrsim$1.5 ($gtrsim$500 au), assuming the Baraffe et al. (2015) models. The images show a radial gap extending to $sim$0.4 ($sim$140 au at a distance of 340 pc) that is also evident in the spectral energy distribution. The large gap is a possible signpost of multiple high-mass giant planets at orbital distances ($sim$60-100 au) that are unusually massive and widely-separated compared to those of planet populations previously inferred from protoplanetary disk substructures.
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