标题： 关于超高能宇宙射线的白皮书 显示英文标题

标题： White Paper on Ultra-High Energy Cosmic Rays

摘要： 一个可以在未来十年内回答的基本问题是：最高能量宇宙射线的起源是什么？ 发现最高能量宇宙射线源将揭示近期宇宙中最活跃天体环境的运行机制。 候选源包括从致密天体的诞生到与伽马射线暴相关的爆炸，或者由活动星系核中超大质量黑洞周围产生。 除了开启高能天文学的新时代，对超高能宇宙射线的研究还将限制银河系和星系际磁场的结构。 这些粒子从源到地球的传播过程也探测了宇宙背景辐射，并提供了对高于地面实验室几个数量级能量的粒子相互作用的见解。 为了在2010年至2020年期间应对这一挑战，需要显著增加超过6×10^19 eV的宇宙射线累积曝光量。 回答这个开放问题的技术能力已经具备，现在正是探索带电粒子天文学的最佳时机。 显示英文摘要

摘要： A fundamental question that can be answered in the next decade is: WHAT IS THE ORIGIN OF THE HIGHEST ENERGY COSMIC PARTICLES? The discovery of the sources of the highest energy cosmic rays will reveal the workings of the most energetic astrophysical environments in the recent universe. Candidate sources range from the birth of compact objects to explosions related to gamma-ray bursts or generated around supermassive black holes in active galactic nuclei. In addition to beginning a new era of high-energy astrophysics, the study of ultra-high energy cosmic rays will constrain the structure of the Galactic and extragalactic magnetic fields. The propagation of these particles from source to Earth also probes the cosmic background radiation and gives insight into particle interactions at orders of magnitude higher energy than can be achieved in terrestrial laboratories. Next generation observatories designed to study the highest energy cosmic rays will have unprecedented sensitivity to ultra-high energy photons and neutrinos, which will further illuminate the workings of the universe at the most extreme energies. For this challenge to be met during the 2010-2020 decade, a significant increase in the integrated exposure to cosmic rays above 6 1019 eV will be necessary. The technical capabilities for answering this open question are at hand and the time is ripe for exploring Charged Particle Astronomy.