Sato T, Sihver L, Iwase H, Nakashima H, Niita K
JAERI, Tokai-mura, Japan.
Adv Space Res. 2005;35(2):208-13. doi: 10.1016/j.asr.2005.01.041.
In order to estimate the biological effects of HZE particles, an accurate knowledge of the physics of interaction of HZE particles is necessary. Since the heavy ion transport problem is a complex one, there is a need for both experimental and theoretical studies to develop accurate transport models. RIST and JAERI (Japan), GSI (Germany) and Chalmers (Sweden) are therefore currently developing and bench marking the General-Purpose Particle and Heavy-Ion Transport code System (PHITS), which is based on the NMTC and MCNP for nucleon/meson and neutron transport respectively, and the JAM hadron cascade model. PHITS uses JAERI Quantum Molecular Dynamics (JQMD) and the Generalized Evaporation Model (GEM) for calculations of fission and evaporation processes, a model developed at NASA Langley for calculation of total reaction cross sections, and the SPAR model for stopping power calculations. The future development of PHITS includes better parameterization in the JQMD model used for the nucleus-nucleus reactions, and improvement of the models used for calculating total reaction cross sections, and addition of routines for calculating elastic scattering of heavy ions, and inclusion of radioactivity and burn up processes. As a part of an extensive bench marking of PHITS, we have compared energy spectra of secondary neutrons created by reactions of HZE particles with different targets, with thicknesses ranging from <1 to 200 cm. We have also compared simulated and measured spatial, fluence and depth-dose distributions from different high energy heavy ion reactions. In this paper, we report simulations of an accelerator-based shielding experiment, in which a beam of 1 GeV/n Fe-ions has passed through thin slabs of polyethylene, Al, and Pb at an acceptance angle up to 4 degrees.
为了评估高能重离子（HZE）粒子的生物学效应，有必要准确了解HZE粒子的相互作用物理过程。由于重离子输运问题很复杂，因此需要通过实验和理论研究来开发精确的输运模型。因此，日本放射医学综合研究所（RIST）和日本原子能研究开发机构（JAERI）、德国重离子研究中心（GSI）以及瑞典查尔姆斯理工大学目前正在开发和基准测试通用粒子与重离子输运代码系统（PHITS），该系统分别基于用于核子/介子输运的NMTC和用于中子输运的MCNP，以及JAM强子级联模型。PHITS使用JAERI量子分子动力学（JQMD）和广义蒸发模型（GEM）来计算裂变和蒸发过程，使用美国国家航空航天局兰利研究中心开发的一个模型来计算总反应截面，并使用SPAR模型来计算阻止本领。PHITS未来的发展包括改进用于核-核反应的JQMD模型中的参数化，改进用于计算总反应截面的模型，添加用于计算重离子弹性散射的程序，以及纳入放射性和燃耗过程。作为对PHITS进行广泛基准测试的一部分，我们比较了HZE粒子与不同靶材反应产生的次级中子能谱，靶材厚度范围从<1厘米到200厘米。我们还比较了不同高能重离子反应的模拟和测量的空间、注量和深度剂量分布。在本文中，我们报告了基于加速器的屏蔽实验的模拟结果，在该实验中，一束1 GeV/n的铁离子束以高达4度的接受角穿过聚乙烯、铝和铅的薄板。
