Astrophysical signatures of dark matter: its nature, the structure of haloes, and galaxy formation

现代宇宙学最显著的成就之一是测量宇宙的基本成分。现在已经确定，普通物质只能占总能量密度的4%。绝大多数（约四分之三）被认为是以神秘的“暗能量”的形式存在，而其余的21%则是由所谓的“暗物质”粒子组成。然而，尽管有越来越多的天体物理学和宇宙学证据证明暗物质的存在，但迄今为止，暗物质还没有被粒子加速器和反冲实验直接探测到。由于最近仪器的进步，通过辐射和相对论粒子的发射进行间接探测已经成为一种有趣的替代方法，许多理论研究已经致力于研究暗物质粒子有效“可见”的条件。这些工作中的大多数有些令人惊讶的结论是，在天体物理尺度上确实可以预期签名，在大多数情况下，它们都在现有的（INTEGRAL，COMPTEL/EGRET）或计划中的（GLAST，Planck）天文台的范围内。事实上，目前的数据已经可以对暗物质的物理性质及其在星系中的分布施加限制。本项目的目的是系统研究不同暗物质模型预期的发射、现有和未来仪器的探测能力及其对星系形成和演化的可能影响，以试图解决“什么是暗物质"这一基本问题。

One of the most remarkable achievements of modern cosmology is the measurement of the fundamental constituents of the Universe. It is now well established that ordinary matter can only account for a mere 4 per cent of the total energy density. The vast majority (about three quarters) is believed to be in the form of a mysterious “dark energy”, while the remaining 21 per cent is composed of so-called “dark matter” particles.Yet, despite the ever increasing amount of astrophysical and cosmological evidence for its existence, dark matter has so far eluded direct detection in particle accelerators and recoil experiments. Thanks to the recent advances in instrumentation, indirect detection through the emission of radiation and relativistic particles has emerged as an interesting alternative, and many theoretical studies have been devoted to investigate the conditions under which dark matter particles would effectively become “visible”.The somewhat surprising conclusion of most of these works is that signatures are indeed expected on astrophysical scales, and in most cases they are within reach of present (INTEGRAL, COMPTEL/EGRET) or planned (GLAST, Planck) observatories. In fact, current data can already impose constraints on both the physical properties of dark matter and on its distribution within galaxies. It is the aim of the present project to make a systematic study of the emission expected for different dark matter models, its detectability by present and forthcoming instruments, and its possible impact on galaxy formation and evolution, in an attempt to address the basic question “What is dark matter?”.