SU-E-T-472：用于生物医学实验规划蒙特卡罗模拟的ALPHA-X激光尾场加速器束线产生的250 MeV（甚高能电子，VHEE）束的甚高能电子特性

SU-E-T-472: Characterization of the Very High Energy Electrons, ISO - 250 MeV (VHEE) Beam Generated by ALPHA-X Laser Wakefield Accelerator Beam Line for Utilization in Monte Carlo Simulation for Biomedical Experiment Planning.

作者信息

Moskvin V, Subiel A, Desrosiers C, Wiggins M, Maryanski M, Mendonca M, Boyd M, Sorensen A, Cipiccia S, Issac R, Welsh G, Brunetti E, Aniculaesei C, Jaroszynski D A

机构信息

Department of Radaition Oncology, Indiana University- School of Medicine, Indianapolis, IN.

SILIS, Department of Physics, University of Strathclyde, Glasgow, UK.

出版信息

Med Phys. 2012 Jun;39(6Part17):3813-3814. doi: 10.1118/1.4735561.

DOI:10.1118/1.4735561

PMID:28517464

Abstract

PURPOSE

Progress in the development of compact high-energy pulsed laser- plasma wakefield accelerators is opening up the potential for using Very High Energy Electron (VHEEs) beams in the range of 150 - 250 MeV for biomedical studies. Initial experiments using VHEE for this purpose have been carried out using the ALPHA-X laser-plasma wakefield accelerator beam line at the University of Strathclyde, Glasgow, UK. The purpose of this investigation is to use Monte Carlo simulations to plan experiments and compare with characterization of the interaction of the VHEE beam using a dosimeter.

METHODS

An experiment using the VHEE beam to irradiate a muscle-equivalent BANG polymer gel dosimeter has been carried out. Simulations have been used to prepare for the experiments. These were undertaken using the expected average energy for a pulse set and an energy spread approximated by Gaussian distribution. The model was implemented in FLUKA Monte Carlo code with follow up modeling using the Geant4 toolkit. The results have been compared with 1mm̂3 voxel laser CT based measurements of the dose deposited in the BANG dosimeter and with measurement of the induced radioactivity.

RESULTS

The results of the measured dose from induced radioactivity have been compared with data from the FLUKA simulations. The beam model based on an average energy of particles in irradiation gives an acceptable estimate of the induced radioactivity and the dose deposited in the BANG dosimeter. Comparison with the dosimeter scanned profiles shows that the structure of the spectra of VHEE beams in the experiment and secondary scattered particles in the beam line should be accounted for in any model. Such model description of the VHEE beam for the ALPHA-X beam line has been developed.

CONCLUSIONS

Monte Carlo simulations using the FLUKA code is an efficient way to plan a VHEE experiment and analyze data from measurements.

摘要

目的

紧凑型高能脉冲激光 - 等离子体尾场加速器的发展进步为在生物医学研究中使用能量范围为150 - 250 MeV的甚高能电子（VHEE）束开辟了潜力。英国格拉斯哥斯特拉斯克莱德大学利用ALPHA - X激光 - 等离子体尾场加速器束线开展了为此目的使用VHEE的初步实验。本研究的目的是利用蒙特卡罗模拟来规划实验，并与使用剂量计对VHEE束相互作用的表征进行比较。

方法

开展了一项使用VHEE束照射肌肉等效BANG聚合物凝胶剂量计的实验。利用模拟为实验做准备。这些模拟是使用一组脉冲的预期平均能量以及由高斯分布近似的能量展宽进行的。该模型在FLUKA蒙特卡罗代码中实现，并使用Geant4工具包进行后续建模。将结果与基于1mm³体素激光CT对BANG剂量计中沉积剂量的测量结果以及对诱导放射性的测量结果进行了比较。

结果

将诱导放射性测量剂量的结果与FLUKA模拟数据进行了比较。基于照射中粒子平均能量的束流模型对诱导放射性以及BANG剂量计中沉积的剂量给出了可接受的估计。与剂量计扫描剖面的比较表明，任何模型都应考虑实验中VHEE束的光谱结构以及束线中的二次散射粒子。已经针对ALPHA - X束线开发了这种VHEE束的模型描述。