Comparison of heavy-ion transport simulations: Collision integral in a box

doi:10.1103/PhysRevC.97.034625

CORC > 上海应用物理研究所 > 中国科学院上海应用物理研究所 > 中科院上海应用物理研究所2011-2017年

	Comparison of heavy-ion transport simulations: Collision integral in a box
	Zhang, YX ; Wang, YJ ; Colonna, M ; Danielewicz, P ; Ono, A ; Tsang, MB ; Wolter, H ; Xu, J ; Chen, LW ; Cozma, D
刊名	PHYSICAL REVIEW C
	2018
卷号	97 期号:3 页码:-
关键词	Boltzmann-langevin Approach Quantum Molecular-dynamics N-body Approach Intermediate Energies Microscopic Models Symmetry Energy Isospin Physics Equation Systems State
ISSN号	2469-9985
DOI	10.1103/PhysRevC.97.034625
文献子类	期刊论文
英文摘要	Simulations by transport codes are indispensable to extract valuable physical information from heavy-ion collisions. In order to understand the origins of discrepancies among different widely used transport codes, we compare 15 such codes under controlled conditions of a system confined to a box with periodic boundary, initialized with Fermi-Dirac distributions at saturation density and temperatures of either 0 or 5 MeV. In such calculations, one is able to check separately the different ingredients of a transport code. In this second publication of the code evaluation project, we only consider the two-body collision term; i.e., we perform cascade calculations. When the Pauli blocking is artificially suppressed, the collision rates are found to be consistent for most codes (to within 1% or better) with analytical results, or completely controlled results of a basic cascade code. In order to reach that goal, it was necessary to eliminate correlations within the same pair of colliding particles that can be present depending on the adopted collision prescription. In calculations with active Pauli blocking, the blocking probability was found to deviate from the expected reference values. The reason is found in substantial phase-space fluctuations and smearing tied to numerical algorithms and model assumptions in the representation of phase space. This results in the reduction of the blocking probability in most transport codes, so that the simulated system gradually evolves away from the Fermi-Dirac toward a Boltzmann distribution. Since the numerical fluctuations are weaker in the Boltzmann-Uehling-Uhlenbeck codes, the Fermi-Dirac statistics is maintained there for a longer time than in the quantum molecular dynamics codes. As a result of this investigation, we are able to make judgements about the most effective strategies in transport simulations for determining the collision probabilities and the Pauli blocking. Investigation in a similar vein of other ingredients in transport calculations, like the mean-field propagation or the production of nucleon resonances and mesons, will be discussed in the future publications.
语种	英语
WOS记录号	WOS:000428777900004
内容类型	期刊论文
源URL	[http://ir.sinap.ac.cn/handle/331007/28946]
专题	上海应用物理研究所_中科院上海应用物理研究所2011-2017年
作者单位	1.Zhang, YX 2.Wang, YJ 3.Colonna, M 4.Danielewicz, P 5.Ono, A 6.Tsang, MB 7.Wolter, H 8.Xu, J 9.Chen, LW 10.Cozma, D
推荐引用方式 GB/T 7714	Zhang, YX,Wang, YJ,Colonna, M,et al. Comparison of heavy-ion transport simulations: Collision integral in a box[J]. PHYSICAL REVIEW C,2018,97(3):-.
APA	Zhang, YX.,Wang, YJ.,Colonna, M.,Danielewicz, P.,Ono, A.,...&Zhang, Z.(2018).Comparison of heavy-ion transport simulations: Collision integral in a box.PHYSICAL REVIEW C,97(3),-.
MLA	Zhang, YX,et al."Comparison of heavy-ion transport simulations: Collision integral in a box".PHYSICAL REVIEW C 97.3(2018):-.