@article{b7ed7408a508490ea9de2ca4d2ef2e2e,
title = "Modeling UV Radiation Feedback from Massive Stars. I. Implementation of Adaptive Ray-tracing Method and Tests",
abstract = "We present an implementation of an adaptive ray-tracing (ART) module in the Athena hydrodynamics code that accurately and efficiently handles the radiative transfer involving multiple point sources on a three-dimensional Cartesian grid. We adopt a recently proposed parallel algorithm that uses nonblocking, asynchronous MPI communications to accelerate transport of rays across the computational domain. We validate our implementation through several standard test problems, including the propagation of radiation in vacuum and the expansions of various types of H ii regions. Additionally, scaling tests show that the cost of a full ray trace per source remains comparable to that of the hydrodynamics update on up to ∼ 103 processors. To demonstrate application of our ART implementation, we perform a simulation of star cluster formation in a marginally bound, turbulent cloud, finding that its star formation efficiency is 12% when both radiation pressure forces and photoionization by UV radiation are treated. We directly compare the radiation forces computed from the ART scheme with those from the M 1 closure relation. Although the ART and M 1 schemes yield similar results on large scales, the latter is unable to resolve the radiation field accurately near individual point sources.",
keywords = "H II regions, methods: numerical, radiation: dynamics, radiative transfer, stars: formation",
author = "Kim, {Jeong Gyu} and Kim, {Woong Tae} and Ostriker, {Eve Charis} and Skinner, {M. Aaron}",
note = "Funding Information: The work of W.-T.K. was supported by the grant (2017R1A4A1015178) of National Research Foundation of Korea. The work of ECO on this project was supported by the U.S. National Science Foundation under grant AST-1312006 and by NASA under grant NNX14AB49G. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. The computation of this work was supported by the Supercomputing Center/Korea Institute of Science and Technology Information with supercomputing resources including technical support (KSC-2015-C3-049) and by the PICSciE TIGRESS High Performance Computing Center at Princeton University. Funding Information: The authors thank Anna Rosen for making a copy of her code and manuscript on adaptive ray tracing available to us before publication. J.-G.K. wishes to thank Shane Davis, Chang-Goo Kim, Jim Stone, Kengo Tomida, and G{\'a}bor T{\'o}th for their helpful discussions and advice. J.-G.K. acknowledges support from the National Research Foundation of Korea (NRF) through the grant NRF-2014-Fostering Core Leaders of the Future Basic Science Program. The work of W.-T.K. was supported by the grant (2017R1A4A1015178) of National Research Foundation of Korea. The work of ECO on this project was supported by the U.S. National Science Foundation under grant AST-1312006 and by NASA under grant NNX14AB49G. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. The computation of this work was supported by the Supercomputing Center/Korea Institute of Science and Technology Information with supercomputing resources including technical support (KSC-2015-C3-049) and by the PICSciE TIGRESS High Performance Computing Center at Princeton University. Publisher Copyright: {\textcopyright} 2017. The American Astronomical Society. All rights reserved.",
year = "2017",
month = dec,
day = "20",
doi = "10.3847/1538-4357/aa9b80",
language = "English (US)",
volume = "851",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2",
}