Single pencil beam benchmark of a module for Monte Carlo simulation of proton transport in the PENELOPE code.
Single pencil beam benchmark of a module for Monte Carlo simulation of proton transport in the PENELOPE code.
复制标题
PENELOPE 代码中质子输运蒙特卡罗模拟模块的单笔形束基准。
DOI：
10.1002/mp.14598
复制
发表时间：
2020
期刊：
影响因子：
3.8
通讯作者：
L. Brualla
中科院分区：
文献类型：
--
作者：
N. Verbeek;J. Wulff;Christian Bӓumer;S. Smyczek;B. Timmermann;L. Brualla
背景和目的
PENH是一个最近编码的模块，用于模拟质子输运与蒙特卡罗代码PENMENTPE。PENDERPE将II类模拟应用于所有类型的相互作用，特别是弹性碰撞。PENH使用计算的质子弹性碰撞的微分截面，包括电子屏蔽效应以及核结构的影响。质子诱发核反应是根据ENDF-6数据库或ENDF格式的替代核数据库中的信息进行模拟的。这项工作的目的是基准这个模块模拟吸收剂量分布从一个单一的有限斑点大小的质子笔束在水中。
材料和方法
使用PENH进行的Monte Carlo模拟与TOPAS Monte Carlo（v3.1p2）和RayStation Monte Carlo（v6）的模拟结果进行了比较。不同的光束模型进行检查的平均能量和能量扩散，以匹配测量的配置文件。相空间文件来自实验测量。模拟的吸收剂量分布进行比较与电离室阵列MatriXX 2D探测器（IBA剂量测定）在水箱中获得的实验数据。实验采用临床IBA笔形束扫描专用喷嘴进行。在所有的模拟费米-Eyges相空间表示的一个单一的有限斑点大小的质子笔束。
结果
在一般情况下，有一个很好的协议之间的模拟结果和实验数据的距离为3厘米的中心轴。在核心区域（剂量超过最大剂量的10%的区域），PENH总体上显示出与实验数据的最小偏差，最大径向均方根（均方根）小于0.2。TOPAS和RayStation在该地区取得的成果与PENH的成果非常接近。对于晕圈区域，即核心区域外的剂量分布区域达到最大强度的0.01%，TOPAS实现的最大均方根始终小于0.5，产生比其余代码更好的结果。
结论
PENDIX PE/PENH代码的物理建模产生的结果与质子治疗相关剂量范围内的测量结果一致。在距离中心束轴大于3 cm处出现的PENH之间的差异是由于该代码中缺乏中子模拟。相比之下，TOPAS有一个更好的协议与实验数据在大的距离从中心束轴，因为模拟的中子。
BACKGROUND AND PURPOSE
PENH is a recently coded module for simulation of proton transport in conjunction with the Monte Carlo code PENELOPE. PENELOPE applies class II simulation to all type of interactions, in particular, to elastic collisions. PENH uses calculated differential cross sections for proton elastic collisions that include electron screening effects as well as nuclear structure effects. Proton-induced nuclear reactions are simulated from information in the ENDF-6 database or from alternative nuclear databases in ENDF format. The purpose of this work is to benchmark this module by simulating absorbed dose distributions from a single finite spot size proton pencil beam in water.
MATERIALS AND METHODS
Monte Carlo simulations with PENH are compared with simulation results from TOPAS Monte Carlo (v3.1p2) and RayStation Monte Carlo (v6). Different beam models are examined in terms of mean energy and energy spread to match the measured profiles. The phase-space file is derived from experimental measurements. Simulated absorbed dose distributions are compared to experimental data obtained with the ionization chamber array MatriXX 2D detector (IBA Dosimetry) in a water tank. The experiments were conducted with a clinical IBA pencil beam scanning dedicated nozzle. In all simulations a Fermi-Eyges phase-space representation of a single finite spot size proton pencil beam is used.
RESULTS
In general, there is a good agreement between simulated results and experimental data up to a distance of 3 cm from the central axis. In the core region (region where the dose is more than 10% of the maximum dose) PENH shows, overall, the smallest deviations from experimental data, with the largest radial rms (root mean square) smaller than 0.2. The results achieved by TOPAS and RayStation in that region are very close to those of PENH. For the halo region, that is the area of the dose distribution outside the core region reaching down to 0.01% of the maximum intensity, the largest rms achieved by TOPAS is always smaller than 0.5, yielding better results than the rest of the codes.
CONCLUSION
The physics modeling of the PENELOPE/PENH code yields results consistent with measurements in the dose range relevant for proton therapy. The discrepancies between PENH appearing at distances larger than 3 cm from the central-beam axis are accountable to the lack of neutron simulation in this code. In contradistinction, TOPAS has a better agreement with experimental data at large distances from the central-beam axis because of the simulation of neutrons.
影响因子：
3.8
作者：
Perl, J.;Shin, J.;Paganetti, H.
通讯作者：
Paganetti, H.