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We model the ALMA and VLA millimeter radial profiles of the disk around HL Tau to constrain the properties of the dust grains. We adopt the disk evolutionary models of Lynden-Bell & Pringle and calculate their temperature and density structure and emission. These disks are heated by the internal viscosity and irradiated by the central star and a warm envelope. We consider a dust size distribution $n(a) da propto a^{-3.5} da $, and vary the maximum grain size in the atmosphere and the midplane, $a_{rm max}=100 mu$m, 1 mm, and 1cm. We also include dust settling and vary the dust-to-gas mass ratio from 1 to 9 times the ISM value. We find that the models that can fit the observed level of emission along the profiles at all wavelengths have an atmosphere with a maximum grain size $a_{rm max} = 100 mu$m, and a midplane with $a_{rm max}=1$ cm. The disk substructure, with a deficit of emission in the gaps, can be due to dust properties in these regions that are different from those in the rings. We test an opacity effect (different $a_{rm max}$) and a dust mass deficit (smaller dust-to-gas mass ratio) in the gaps. We find that the emission profiles are better reproduced by models with a dust deficit in the gaps, although a combined effect is also possible. These models have a global dust-to-gas mass ratio twice the ISM value, needed to reach the level of emission of the 7.8 mm VLA profile.
The first long-baseline ALMA campaign resolved the disk around the young star HL Tau into a number of axisymmetric bright and dark rings. Despite the very young age of HL Tau these structures have been interpreted as signatures for the presence of (p
The protoplanetary disk around HL Tau is so far the youngest candidate of planet formation, and it is still embedded in a protostellar envelope with a size of thousands of au. In this work, we study the gas kinematics in the envelope and its possible
Recent ALMA images of HL Tau show gaps in the dusty disk that may be caused by planetary bodies. Given the young age of this system, if confirmed, this finding would imply very short timescales for planet formation, probably in a gravitationally unst
We used new ALMA $^{13}$CO and C$^{18}$O(3-2) observations obtained at high angular resolution ($sim$0.2) together with previous CO(3-2) and (6-5) ALMA data and continuum maps at 1.3 and 0.8 mm in order to determine the gas properties (temperature, d
We present a self-consistent model of a protoplanetary disk: ANDES (AccretioN disk with Dust Evolution and Sedimentation). ANDES is based on a flexible and extendable modular structure that includes 1) a 1+1D frequency-dependent continuum radiative t