In high-energy physics, Monte Carlo event generators (MCEGs) are used to simulate the interactions of high energy particles. MCEG event records store the information on the simulated particles and their relationships, and thus reflects the simulated evolution of physics phenomena in each collision event. We present the HepMC3 library, a next-generation framework for MCEG event record encoding and manipulation, which builds on the functionality of its widely-used predecessors to enable more sophisticated algorithms for event-record analysis. By comparison to previous versions, the event record structure has been simplified, while adding the possibility to encode arbitrary information. The I/O functionality has been extended to support common input and output formats of various HEP MCEGs, including formats used in Fortran MCEGs, the formats established by the HepMC2 library, and binary formats such as ROOT; custom input or output handlers may also be used. HepMC3 is already supported by popular modern MCEGs and can replace the older HepMC versions in many others.

中文翻译：

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蒙特卡罗事件生成器的 HepMC3 事件记录库

在高能物理学中，蒙特卡罗事件发生器 (MCEG) 用于模拟高能粒子的相互作用。MCEG事件记录存储了模拟粒子及其关系的信息，从而反映了每次碰撞事件中物理现象的模拟演化。我们展示了 HepMC3 库，它是 MCEG 事件记录编码和操作的下一代框架，它建立在其广泛使用的前辈的功能之上，为事件记录分析启用更复杂的算法。与以前的版本相比，事件记录结构得到了简化，同时增加了对任意信息进行编码的可能性。I/O 功能已扩展为支持各种 HEP MCEG 的通用输入和输出格式，包括 Fortran MCEG 中使用的格式，HepMC2库建立的格式，以及ROOT等二进制格式；也可以使用自定义输入或输出处理程序。HepMC3 已经得到流行的现代 MCEG 的支持，并且可以在许多其他版本中替换旧的 HepMC 版本。