URANOS v1.0

The understanding of neutron transport by Monte-Carlo simulations led to major advancements towards precise interpretation of measurements. URANOS (Ultra Rapid Neutron-Only Simulation) is a free software package, which has been developed in the last years in a cooperation of Particle Physics and Environmental Sciences, specifically for the purposes of cosmic-ray neutron sensing (CRNS). Its versatile user interface and input/output scheme tailored for CRNS applications offers hydrologists a straightforward access to model individual scenarios and to directly perform advanced neutron transport calculations. The geometry can be modeled layerwise, whereas in each layer a voxel geometry is extruded using a two-dimensional map from pixel images representing predefined materials and allowing to construct objects on the basis of pixel graphics without a 3D editor. It furthermore features predefined cosmic-ray neutron spectra and detector configurations and allows also a replication of important site characteristics of study areas – from a small pond to the catchment scale. The simulation thereby gives precise answers to questions like: From which location do neutrons originate? How do they propagate to the sensor? What is the neutron response to certain environmental changes? In recent years, URANOS has been successfully employed by a number of studies, for example, to calculate the cosmic-ray neutron footprint, signals in complex geometries like mobile applications on roads, urban environments and snow patterns.借助蒙特卡洛模拟（Monte-Carlo simulations）开展中子输运研究，为精准解析测量结果带来了重大进展。URANOS（Ultra Rapid Neutron-Only Simulation）是一款免费软件包，由粒子物理与环境科学领域的合作团队历时多年研发，专为宇宙射线中子传感（cosmic-ray neutron sensing, CRNS）场景定制。其多功能用户界面与适配CRNS应用的输入输出架构，为水文学家提供了便捷的单个场景建模途径，可直接开展高级中子输运计算。该软件支持分层式几何建模：每层均可通过代表预设材料的像素图像生成二维映射图，进而挤出体素几何（voxel geometry），无需借助3D编辑器即可基于像素图形构建研究对象。此外，URANOS内置预设的宇宙射线中子能谱与探测器配置方案，可复刻研究区域的关键场地特征，覆盖从小型水塘到流域尺度的各类场景。该模拟可精准解答如下问题：中子源自何处？它们如何传播至探测器？中子对特定环境变化的响应如何？近年来，URANOS已被多项研究成功应用，例如用于计算宇宙射线中子足迹，以及道路移动应用、城市环境与积雪模式等复杂几何场景下的中子信号。