{"paper":{"title":"A Two-moment Radiation Hydrodynamics Module in Athena Using a Time-explicit Godunov Method","arxiv_id":"1306.0010","primary_cat":"astro-ph.IM","submitted_at":"2013-05-31T20:00:04+00:00","version_compiled":"v1"},"notice":"Every quoted sentence is the authors' text from the arXiv listing abstract. Labels and probabilities are the outputs of classifier-1.13-20260917 on the question bank abstract-p1-20260923, exactly as returned. 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costs.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.94,"main_claim_p":0.04,"quantitative":false,"quantitative_p":0.07,"role_probabilities":{"gap":0.0,"method":1.0,"result":0.0,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.0}},{"i":4,"p":0.97,"id":"s4","own":true,"role":"method","text":"Our code is dimensionally unsplit in one, two, and three space dimensions and is parallelized using MPI.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.94,"main_claim_p":0.04,"quantitative":true,"quantitative_p":0.56,"role_probabilities":{"gap":0.0,"method":0.97,"result":0.0,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.03,"interpretation":0.0}},{"i":5,"p":0.88,"id":"s5","own":true,"role":"result","text":"The streaming and diffusion limits are well-described by the M1 closure model, and our implementation shows excellent behavior for a problem with a concentrated radiation source containing both regimes simultaneously.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.92,"main_claim_p":0.19,"quantitative":false,"quantitative_p":0.15,"role_probabilities":{"gap":0.0,"method":0.0,"result":0.88,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.0,"interpretation":0.12}},{"i":6,"p":0.91,"id":"s6","own":true,"role":"limitation","text":"Our operator-split method is ideally suited for problems with a slowly varying radiation field and dynamical gas flows, in which the effect of the RSLA is minimal.","hedge":{"p":0.99,"label":"asserted"},"own_p":0.53,"main_claim_p":0.09,"quantitative":false,"quantitative_p":0.11,"role_probabilities":{"gap":0.0,"method":0.02,"result":0.0,"background":0.0,"limitation":0.91,"future_work":0.0,"contribution":0.0,"interpretation":0.07}},{"i":7,"p":0.83,"id":"s7","own":true,"role":"contribution","text":"We present an analysis of the dispersion relation of RHD linear waves highlighting the conditions of applicability for the RSLA.","hedge":{"p":0.96,"label":"asserted"},"own_p":0.93,"main_claim_p":0.07,"quantitative":false,"quantitative_p":0.06,"role_probabilities":{"gap":0.0,"method":0.14,"result":0.02,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.83,"interpretation":0.01}},{"i":8,"p":0.85,"id":"s8","own":true,"role":"result","text":"To demonstrate the accuracy of our method, we utilize a suite of radiation and RHD tests covering a broad range of regimes, including RHD waves, shocks, and equilibria, which show second-order convergence in most cases.","hedge":{"p":1.0,"label":"asserted"},"own_p":0.96,"main_claim_p":0.15,"quantitative":true,"quantitative_p":0.89,"role_probabilities":{"gap":0.0,"method":0.1,"result":0.85,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.05,"interpretation":0.0}},{"i":9,"p":0.91,"id":"s9","own":true,"role":"contribution","text":"As an application, we investigate radiation-driven ejection of a dusty, optically thick shell in the interstellar medium (ISM).","hedge":{"p":0.98,"label":"asserted"},"own_p":0.95,"main_claim_p":0.07,"quantitative":false,"quantitative_p":0.04,"role_probabilities":{"gap":0.0,"method":0.01,"result":0.08,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.91,"interpretation":0.0}},{"i":10,"p":0.52,"id":"s10","own":true,"role":"contribution","text":"Finally, we compare the timing of our method with other well-known iterative schemes for the RHD equations.","hedge":{"p":0.89,"label":"asserted"},"own_p":0.94,"main_claim_p":0.04,"quantitative":true,"quantitative_p":0.53,"role_probabilities":{"gap":0.0,"method":0.17,"result":0.31,"background":0.0,"limitation":0.0,"future_work":0.0,"contribution":0.52,"interpretation":0.0}},{"i":11,"p":0.54,"id":"s11","own":true,"role":"contribution","text":"Our code implementation, Hyperion, is suitable for a wide variety of astrophysical applications and will be made freely available on the 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