Millimeter gap contrast as a probe for turbulence level in protoplanetary disks

作     者：Yao Liu Gesa H.-M.Bertrang Mario Flock Giovanni P.Rosotti Ewine F.van Dishoeck Yann Boehler Stefano Facchini Can Cui Sebastian Wolf Min Fang 

作者机构：Max-Planck-Institut für Extraterrestrische PhysikGarching85748Germany Purple Mountain Observatory&Key Laboratory for Radio AstronomyChinese Academy of SciencesNanjing210023China Max-Planck-Institut für AstronomieHeidelbergD-69117Germany Leiden ObservatoryLeiden UniversityLeidenNL-2300the Netherlands School of Physics and AstronomyUniversity of LeicesterLeicesterLE17RHUK UniversitéGrenoble AlpesFrench National Centre for Scientific ResearchInstitute for Planetary Sciences and AstrophysicsGrenobleGrenobleF-38000France European Southern ObservatoryGarching85748Germany Department of Applied Mathematics and Theoretical PhysicsUniversity of CambridgeCentre for Mathematical SciencesCambridgeCB3 OWAUK Institut für Theoretische Physik und AstrophysikChristian-Albrechts-Universität zu kielKiel24118Germany 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学：物理学、力学、天文学（英文版）)

年 卷 期：2022年第65卷第12期

页      面：131-144页

核心收录：

学科分类：07[理学] 070401[理学-天体物理] 0704[理学-天文学] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.11973090) the Science Research Grants from the China Manned Space Project(Grant No.CMS-CSST-2021-B06) supported by the European Research Council(ERC)under the European Union’s Horizon 2020 Research and Innovation Program(Grant No.757957) supported by the Netherlands Organisation for Scientific Research(Grant No.016.Veni.192.233) STFC Ernest Rutherford Fellowship(Grant No.ST/T003855/1)。 

主　　题：protoplanetary disks radiative transfer planet formation 

摘      要：Turbulent motions are believed to regulate angular momentum transport and influence dust evolution in protoplanetary disks.Measuring the strength of turbulence is challenging through gas line observations because of the requirement for high spatial and spectral resolution data,and an exquisite determination of the temperature.In this work,taking the well-known HD 163296 disk as an example,we investigated the contrast of gaps identified in high angular resolution continuum images as a probe for the level of turbulence.With self-consistent radiative transfer models,we simultaneously analyzed the radial brightness profiles along the disk major and minor axes,and the azimuthal brightness profiles of the B67 and B100 rings.By fitting all the gap contrasts measured from these profiles,we constrained the gas-to-dust scale height ratioΛto be 3.0^(+0.3)_(−0.8),1.2^(+0.1)_(−0.1),and≥6.5 for the D48,B67,and B100 regions,respectively.The varying gas-to-dust scale height ratios indicate that the degree of dust settling changes with radius.The inferred values forΛtranslate into a turbulence level of α_(turb)3×10^(−3) in the D48 and B100 regions,which is consistent with previous upper limits set by gas line observations.However,turbulent motions in the B67 ring are strong with α_(turb)∼1.2×10^(−2).Due to the degeneracy betweenΛand the depth of dust surface density drops,the turbulence strength in the D86 gap region is not constrained.