KARL - a Monte Carlo model for atomic and molecular processes in the tritium atmosphere of the KATRIN experiment

IF 7.2 2区物理与天体物理 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computer Physics Communications Pub Date : 2025-03-17 DOI:10.1016/j.cpc.2025.109580

Christian Sendlinger , Jonas Kellerer , Felix Spanier

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引用次数: 0

Abstract

A new parallelized simulation code is presented, which uses a Monte Carlo method to determine particle spectra in the KATRIN source. Reaction chains are generated from the decay of tritium within the source. The code includes all relevant processes: elastic scattering, ionization, excitation (electric, vibrational, rotational), recombination and various clustering processes. The main emphasis of the code is the calculation of particle spectra and particle densities and currents at specific points within the source. It features a new technique to determine these quantities. It also calculates target fields for the interaction of particles with each other as it is needed for recombination processes.

The code has been designed for the KATRIN experiment but is easily adaptable for other tritium based experiments like Project 8. Geometry and background tritium gas flow can be given as user input.

The code is parallelized using MPI and writes output using HDF5. Input to the simulation is read from a JSON description.

Program summary

Program Title: KARL - KAtrin WGTS electRon and ion spectrum Monte CarLo

CPC Library link to program files: https://doi.org/10.17632/5bj3vwc6rg.1

Licensing provisions: GNU Public License v3

Programming language: C++

External routines/libraries: C++ compiler (tested with g++ 8.2 and 9.4.0), MPI 1.1 (tested with OpenMPI 3.1), HDF5 with support for parallel I/O (tested with version 1.10.0), Blitz++ (tested with version 1.0.2), Jansson (tested with version 2.12 and 2.13)

Nature of problem: In the KATRIN experiment (and other experiments alike that feature large vessels filled with tritium) electrons are created from beta decay. These electrons interact with the ambient gas to produce secondary electrons through ionization. Subsequent processes include excitation, secondary ionization and collisions. The resulting electron and ion differential energy spectrum at various positions is relevant for further plasma analysis, and the current of charged particles to the ends of the experiments is an observable.

Solution method: Semi-classical Monte Carlo.

Additional comments including restrictions and unusual features: The geometry of the experiment is currently limited to the KATRIN experiment, but this may easily be changed. The configuration is stored in JSON files.

查看原文本刊更多论文

KATRIN实验中氚大气中原子和分子过程的蒙特卡罗模型

提出了一种新的并行化仿真代码，利用蒙特卡罗方法确定KATRIN源中的粒子谱。反应链是由氚在源内的衰变产生的。代码包括所有相关过程：弹性散射，电离，激发（电，振动，旋转），重组和各种聚类过程。该代码的主要重点是计算粒子谱和粒子密度以及源内特定点的电流。它采用了一种新技术来确定这些数量。它还计算粒子相互作用的目标场，因为这是重组过程所需要的。该代码是为KATRIN实验设计的，但很容易适用于其他基于氚的实验，如项目8。几何形状和背景氚气体流量可以作为用户输入。代码使用MPI并行化，并使用HDF5写入输出。模拟的输入是从JSON描述中读取的。程序摘要程序标题：KARL - KAtrin WGTS电子和离子频谱Monte CarLoCPC库链接到程序文件：https://doi.org/10.17632/5bj3vwc6rg.1Licensing条款：GNU公共许可证v3编程语言：c++外部例程/库：c++编译器（用g++ 8.2和9.4.0测试），MPI 1.1（用OpenMPI 3.1测试），支持并行I/O的HDF5（用1.10.0版本测试），Blitz++（用1.0.2版本测试），Jansson（用2.12和2.13版本测试）问题性质：在KATRIN实验（以及其他类似的实验，这些实验的特点是装满氚的大容器）中，电子是由β衰变产生的。这些电子与周围气体相互作用，通过电离产生二次电子。随后的过程包括激发、二次电离和碰撞。所得的电子和离子在不同位置的差能谱与进一步的等离子体分析有关，并且实验结束时带电粒子的电流是可观察到的。求解方法：半经典蒙特卡罗。附加评论包括限制和不寻常的特征：实验的几何形状目前仅限于KATRIN实验，但这可能很容易改变。配置存储在JSON文件中。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Computer Physics Communications 物理-计算机：跨学科应用

CiteScore

12.10

自引率

3.20%

发文量

287

审稿时长

5.3 months

期刊介绍： The focus of CPC is on contemporary computational methods and techniques and their implementation, the effectiveness of which will normally be evidenced by the author(s) within the context of a substantive problem in physics. Within this setting CPC publishes two types of paper. Computer Programs in Physics (CPiP) These papers describe significant computer programs to be archived in the CPC Program Library which is held in the Mendeley Data repository. The submitted software must be covered by an approved open source licence. Papers and associated computer programs that address a problem of contemporary interest in physics that cannot be solved by current software are particularly encouraged. Computational Physics Papers (CP) These are research papers in, but are not limited to, the following themes across computational physics and related disciplines. mathematical and numerical methods and algorithms; computational models including those associated with the design, control and analysis of experiments; and algebraic computation. Each will normally include software implementation and performance details. The software implementation should, ideally, be available via GitHub, Zenodo or an institutional repository.In addition, research papers on the impact of advanced computer architecture and special purpose computers on computing in the physical sciences and software topics related to, and of importance in, the physical sciences may be considered.