The reliability of approximate radiation transport methods for irradiated disk studies

Abstract

Context: Dynamical studies of irradiated circumstellar disks require an accurate treatment of radiation transport to, for example, properly determine cooling and fragmentation properties. The radiation transport algorithm should be as fast as the (magneto-) hydrodynamics to allow for an efficient usage of computing resources. Methods: We use a setup of a central star and a slightly flared circumstellar disk. We perform simulations for a wide range of optical depths of the disk's midplane from tau(550nm) = 0.1 up to tau(810nm) = 1 million. We check the accuracy of the gray flux-limited diffusion (FLD) approximation and a gray and frequency-dependent ray-tracing plus FLD approximation. Results: 1. For moderate optical depths, a gray approximation of the stellar irradiation yields a slightly hotter inner rim and a slightly cooler midplane of the disk at larger radii, but is otherwise in agreement with the frequency-dependent treatment. 2. The gray FLD approximation fails to compute an appropriate temperature profile in all regimes of optical depth; the maximum deviations to the comparison runs are 50 percent in the optically thin and up to 280 percent in the optically thick limit. For low optical depth, the isotropic assumption within the FLD method yields a too steep decrease of the radial temperature slope. For higher optical depths, the FLD approximation does not reproduce the shadow behind the optically thick inner rim of the circumstellar disk, yielding artificial heating at larger disk radii. 3. The frequency-dependent RT + gray FLD approximation yields remarkable accuracy for the whole range of optical depths. Conclusions: The high accuracy of the frequency-dependent hybrid radiation transport algorithm makes this method ideally suited for (magneto-) hydrodynamical studies of irradiated circumstellar disks.

8 pages, accepted for publication at A&A; abstract is highly abbreviated

References in corpus (9)

• Circumventing the radiation pressure barrier in the formation of massive stars via disk accretion
• Three-dimensional simulation of massive star formation in the disk accretion scenario
• Fragmentation of Massive Protostellar Disks
• Global Models for the Evolution of Embedded, Accreting Protostellar Disks
• Stellar irradiated discs and implications on migration of embedded planets I: equilibrium discs
• Vortices in Thin, Compressible, Unmagnetized Disks
• 3D Radiative Hydrodynamics for Disk Stability Simulations: A Proposed Testing Standard and New Results
• Accretion disks around massive stars: Hydrodynamic structure, stability and dust sublimation
• On the effects of optically thick gas (disks) around massive stars

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