Proton structure, high energy neutrinos, and dark matter searches

对于超高能宇宙射线(UHECR)、高能中微子和暗物质信号的天体物理研究来说，关于强子碰撞中正向粒子产生的精确知识是至关重要的。虽然目前在大型强子对撞机(LHC)上的实验提供了许多有价值的相关信息，但人们通常需要一个自洽的理论方法，包括处理非微扰质子结构，将所有实验数据组合成一幅连贯的图片，并在测量的运动学区域之外和各种相互作用过程中提供可靠的预测。本项目的主要目标是开发一种先进的蒙特卡罗(MC)处理方法，用于在强子和核碰撞中产生正向粒子，包括魅力强子，并将其应用于与UHECR研究、高能中微子研究和暗物质搜索有关的各种天体物理问题。提出的科学计划的核心内容是一种连贯的理论方法，用于处理非微扰成分Parton Fock态，包括那些包含重夸克的成分，并将其纳入QGSJET-II MC强子碰撞产生器。将新模型应用于大气中UHECR相互作用的处理和CR质量组成的分析，将使申请人能够解决目前与UHECR研究有关的许多难题，这既涉及对目前和即将到来的宇宙线数据的自洽解释，也涉及对各种UHECR源模型的区分。对MC产生器的推广用于处理迷人的强子产生，包括非微扰的固有魅力贡献，将为一些UHECR源模型可靠地计算大气中微子背景和天体物理中微子通量奠定基础。推广QGSJET-II模型来处理反核的产生，使用当代的聚结方法，将是朝着可靠的计算间接暗物质搜索的背景迈出的重要一步。该项目的跨学科性质与这样一个事实有关，即拟议的发展将形成一座桥梁，从大型强子对撞机的实验到属于高能天体物理领域的实验，从而使后者能够从大型强子对撞机庞大而多样的实验计划中受益。

The precise knowledge about forward particle production in hadronic collisions is of paramount importance for astrophysical studies of ultra-high energy cosmic rays (UHECRs), high energy neutrinos, and dark matter signals. While many valuable pieces of the relevant information are furnished by the present experiments at the Large Hadron Collider (LHC), one generally needs a self-consistent theoretical approach, including a treatment of the nonperturbative proton structure, to combine all the experimental data into a coherent picture and to provide reliable predictions outside the measured kinematic regions and for various interaction processes. The main goals of the present project are to develop an advanced Monte Carlo (MC) treatment of forward particle production, including charmed hadrons, in hadronic and nuclear collisions and to apply it to various astrophysical problems related to investigations of UHECRs, of high energy neutrinos, and to dark matter searches. The core element of the proposed scientific program is a coherent theoretical approach to the treatment of nonperturbative constituent parton Fock states, including those containing heavy quarks, and its incorporation into the QGSJET-II MC generator of hadronic collisions. Applications of the new model to the treatment of UHECR interactions in the atmosphere and to an analysis of the CR mass composition will allow the applicant to address many current puzzles related to UHECR studies, concerning both a self-consistent interpretation of the present and forthcoming cosmic ray data, and to a discrimination between various UHECR source models. A generalization of the MC generator for a treatment of charmed hadron production, including the nonperturbative intrinsic charm contribution, will form the basis for a reliable calculation of the atmospheric neutrino background and of astrophysical neutrino fluxes, for a number of UHECR source models. A generalization of the QGSJET-II model to treat the production of antinuclei, using a contemporary coalescence approach, will be an important step towards reliable calculations of backgrounds for indirect dark matter searches. The interdisciplinary character of the project is related to the fact that the proposed developments will form a bridge from the experiments at the Large Hadron Collider to the ones belonging to the high energy astrophysics field, thus allowing the latter to benefit from the vast and diverse experimental program at the LHC.