Hadronic interactions: From LHC to Ultra-High Energy Cosmic Rays

高能宇宙射线数据的解释和超高能宇宙射线起源之谜的解决在很大程度上取决于强子蒙特卡罗模型的有效性，而强子蒙特卡罗模型是描述宇宙射线粒子在大气中的相互作用所必需的。该项目旨在进一步发展现代强子蒙特卡罗发生器，充分利用新的理论方法和现有的和即将到来的加速器数据。这种改进的蒙特卡罗发生器的核心元素是在现有的qgsjt - ii模型中，基于与多部分子相互作用相关的非线性相互作用效应的微扰描述，实现强子和核碰撞的自洽处理。该模型将通过相关加速器数据进行彻底测试和校准，特别是来自大型强子对撞机的数据。它将应用于宇宙射线引起的大面积空气阵雨的特性计算。将结果与皮埃尔·奥格天文台的实验数据进行比较，得出超高能宇宙射线通量的核组成结论。该项目的跨学科方面是双重的：首先，现代理论方法和加速器数据将用于开发高能宇宙射线研究的可靠工具。其次，所开发的模型将在对撞机物理中有广泛的应用，例如在强子和核相互作用、软硬衍射和多部分子相互作用中一般最小偏倚碰撞的研究。

The interpretation of high energy cosmic ray data and the solution of the enigma of the origin of ultra-high energy cosmic rays depend crucially on the validity of hadronic Monte Carlo models which are required for the description of the interactions of cosmic ray particles in the atmosphere. The project is aimed at the further development of a modern hadronic Monte Carlo generator, taking the full advantage of new theoretical approaches and of existing and forthcoming accelerator data. Core element of this improved Monte Carlo generator is the implementation of a self-consistent treatment of hadronic and nuclear collisions, based on the perturbative description of nonlinear interaction effects related to multi-parton interactions, into the existing QGSJET-II model. The model will be thoroughly tested and calibrated with relevant accelerator data, notably, from the Large Hadron Collider. It will be applied to the calculations of characteristics of cosmic ray induced extensive air showers. The results will be compared to experimental data of the Pierre Auger Observatory and conclusions on the nuclear composition of the ultra-high energy cosmic ray flux will be drawn. The interdisciplinary aspect of the project is twofold: First, modern theoretical approaches and accelerator data will be used to develop a reliable tool for high energy cosmic ray studies. Secondly, the developed model will have a vast range of applications in collider physics, e.g. in relation to studies of general minimum bias collisions in hadronic and nuclear interactions, soft and hard diffraction, and multi-parton interactions.