TY - JOUR

T1 - Global Hydromagnetic Simulations of Protoplanetary Disks with Stellar Irradiation and Simplified Thermochemistry

AU - Gressel, Oliver

AU - Ramsey, Jon P.

AU - Brinch, Christian

AU - Nelson, Richard P.

AU - Turner, Neal J.

AU - Bruderer, Simon

PY - 2020/6/1

Y1 - 2020/6/1

N2 - Outflows driven by large-scale magnetic fields likely play an important role in the evolution and dispersal of protoplanetary disks and in setting the conditions for planet formation. We extend our 2D-axisymmetric nonideal MHD model of these outflows by incorporating radiative transfer and simplified thermochemistry, with the dual aims of exploring how heating influences wind launching and illustrating how such models can be tested through observations of diagnostic spectral lines. Our model disks launch magnetocentrifugal outflows primarily through magnetic tension forces, so the mass-loss rate increases only moderately when thermochemical effects are switched on. For typical field strengths, thermochemical and irradiation heating are more important than magnetic dissipation. We furthermore find that the entrained vertical magnetic flux diffuses out of the disk on secular timescales as a result of nonideal MHD. Through postprocessing line radiative transfer, we demonstrate that spectral line intensities and moment-1 maps of atomic oxygen, the HCN molecule, and other species show potentially observable differences between a model with a magnetically driven outflow and one with a weaker, photoevaporative outflow. In particular, the line shapes and velocity asymmetries in the moment-1 maps could enable the identification of outflows emanating from the disk surface.

AB - Outflows driven by large-scale magnetic fields likely play an important role in the evolution and dispersal of protoplanetary disks and in setting the conditions for planet formation. We extend our 2D-axisymmetric nonideal MHD model of these outflows by incorporating radiative transfer and simplified thermochemistry, with the dual aims of exploring how heating influences wind launching and illustrating how such models can be tested through observations of diagnostic spectral lines. Our model disks launch magnetocentrifugal outflows primarily through magnetic tension forces, so the mass-loss rate increases only moderately when thermochemical effects are switched on. For typical field strengths, thermochemical and irradiation heating are more important than magnetic dissipation. We furthermore find that the entrained vertical magnetic flux diffuses out of the disk on secular timescales as a result of nonideal MHD. Through postprocessing line radiative transfer, we demonstrate that spectral line intensities and moment-1 maps of atomic oxygen, the HCN molecule, and other species show potentially observable differences between a model with a magnetically driven outflow and one with a weaker, photoevaporative outflow. In particular, the line shapes and velocity asymmetries in the moment-1 maps could enable the identification of outflows emanating from the disk surface.

KW - Magnetohydrodynamics

KW - Radiative transfer simulations

KW - Stellar accretion disks

KW - Astrochemistry

KW - Protoplanetary disks

KW - VERTICAL SHEAR INSTABILITY

KW - WEAKLY MAGNETIZED DISKS

KW - MASS PLANET MIGRATION

KW - TORQUED DEAD ZONES

KW - ACCRETION DISKS

KW - PHOTODISSOCIATION REGIONS

KW - CONSTRAINED TRANSPORT

KW - MHD SIMULATIONS

KW - MAGNETOROTATIONAL INSTABILITY

KW - MAGNETOHYDRODYNAMICS CODE

U2 - 10.3847/1538-4357/ab91b7

DO - 10.3847/1538-4357/ab91b7

M3 - Journal article

VL - 896

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 126

ER -