论文标题
蒙特卡洛模拟方法在激光康普顿散射对相对论电子的极化效应方法
Monte Carlo simulation method of polarization effects in Laser Compton Scattering on relativistic electrons
论文作者
论文摘要
基于相对论电子的激光光子（LCS）基于激光光子的康普顿散射（LCS）的准单色，高能量和高度极化的$γ$射线光束源已在过去的几十年中作为已建立的核物理学仪器开发。在日本Spring8的LCS $γ$ -Ray光束线的LCS $γ$ -Ray光束线进行了广泛的Photoneutron实验活动之后，开发了专门的模拟代码，以表征事件$γ$ -Ray射线。 Elilabr代码是使用Geant4实现的，可在https://github.com/dan-mihai-filipescu/elilabr上在GitHub存储库中使用。目前的工作描述了蒙特卡洛算法的逐步描述，重点是建模散射光子的极化特性。在Stokes参数和极化矢量形式主义中，都可以独立处理极化。给出了两种方法之间的间隔。基于两极分化geant4物理类别的极化状态描述要求，给出了用户建议使用的两种方法中的哪种。 LCS $γ$ ray梁及其Stokes参数的空间和能量分布是用于正面激光的 - 相对论电子碰撞的，其中考虑了几种入射激光极化状态：线性，非极化，圆形，圆形和混合线性和圆形偏振。 还研究了光子和电子束之间可变入射角的影响。我们表明，从入射光子到散射光子的极化转移程度随碰撞角增加。但是，我们表明，对于基于相对论电子上激光光子的康普顿散射的$γ$射线源，入射光子的极化度几乎完全传递到散射光子上，以进行任何入射角。
Quasi-monochromatic, high energy and highly polarized $γ$-ray beam sources based on Compton scattering of laser photons (LCS) on relativistic electrons have developed for the last few decades as established instruments for nuclear physics studies. Following an extensive photoneutron experimental campaign at the LCS $γ$-ray beam line of the NewSUBARU synchrotron radiation facility at SPring8, Japan, a dedicated simulation code was developed for characterizing the incident $γ$-ray beams. The eliLaBr code is implemented using Geant4 and is available on the GitHub repository, at https://github.com/dan-mihai-filipescu/eliLaBr . The present work describes step-by-step the Monte Carlo algorithm with focus on modeling the polarization properties of the scattered photon. The polarization is treated independently both in the Stokes parameters and in the polarization vector formalisms. An intervalidation between the two methods is given. Based on polarization state description requirements of different Geant4 physics classes, user recommendations are given on which of the two methods to be employed. The spatial and energy distributions for the LCS $γ$-ray beam and its Stokes parameters are obtained for head-on laser - relativistic electron collisions, where several incident laser polarization states were considered: linear, unpolarized, circular and mixed linear and circular polarization. The influence of variable incident angle between photon and electron beam was also investigated. We show that the degree of polarization transfer from the incident photon to the scattered photon increases with the collision angle. However, we show that, for $γ$-ray sources based on Compton scattering of laser photons on relativistic electrons, the polarization degree of the incident photon is almost completely transferred to the scattered photon for any incident angle.
