Dwarf Galaxies and the Nature of Dark Matter

矮星系和暗物质的本质

基本信息

批准号：
RGPIN-2014-05647
负责人：
Navarro, Julio
金额：
$ 4.52万
依托单位：
University of Victoria
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2015
资助国家：
加拿大
起止时间：
2015-01-01 至 2016-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=588532
关键词：
Dwarf Galaxies Nature Dark Matter

项目摘要

The past few decades have seen the emergence of a paradigm for the content and geometry of the Universe. This paradigm (usually referred to by its acronym LCDM) envisions the matter-energy content of the Universe as dominated by the evolving balance between radiation and two exotic components: cold dark matter and dark energy. However improbable this may sound, LCDM successfully accounts for most cosmological observations on large scales, and is widely regarded as the first successful cosmological theory ever devised. Its success on large scales notwithstanding, LCDM makes predictions on small scales that apparently run into conflict with observations of faint galaxies. These issues have surfaced as the completion of photometric and redshift surveys of large portions of the sky has revolutionized our understanding of faint galaxies, extending the inventory of dwarf galaxies to luminosities so faint that they blur the traditional distinction between galaxies and star clusters. These observations have highlighted potentially fatal challenges to LCDM on small scales, including the lack of a conspicuous “cusp” of dark matter at the center of dwarf galaxies; the scarcity of low-mass galaxies compared with the huge predicted abundance of low-mass dark matter halos capable, in principle, of hosting them; as well as oddities in the kinematic and spatial arrangement of the dwarf satellites of the Milky Way and Andromeda galaxies. All of these problems are the subject of active investigation, especially since plausible (but radical) modifications to the LCDM paradigm, such as “warm” or “self-interacting” dark matter, provide attractive alternatives. The confrontation of data with LCDM predictions for the smallest galaxies known thus holds the promise to validate or challenge the established paradigm on scales far removed from those used to tune its main parameters. The time seems ripe for a concerted effort designed to assess the cosmological significance of Nature's smallest extragalactic objects. I propose to study this topic using a variety of observational and theoretical tools, from detailed N-body simulation of the formation of dark matter halos, to gas-dynamical simulation of the formation of luminous dwarf galaxies, to direct observational efforts designed to survey the faintest galaxies in our Local Universe and to understand their impact on the formation of our Milky Way galaxy.

过去几十年来，宇宙的内容和几何形状都构想了物质 - 能源是由辐射和两个外来组成部分之间的演变而来的。被广泛认为是每一个设计的最奇特理论。它们模糊了星系和星形群之间的交易，这些观察结果可能在小尺度上突出了致命的LCDD M，这涉及缺乏矮人星系中心的暗物质的“ cusp”。与原则上的低含量晕圈的巨大预测相比，它们的矮人和仙女座星系的矮人卫星的无数量和空间排列。范式，例如“暗物质”提供了有吸引力的替代方案。与已知的小型有关的LCDM预测的数据对抗，因此有望在远离使用的主参数的范围内验证或挑战范式。设计为宇宙学的最小对物体的意义，使用各种观测和理论工具，从详细的N-body模拟暗物质晕圈的形成。我们当地宇宙中的星系，并了解对我们米尔基（Millky Way）银河系形成的影响。