Astrophysics and Cosmology at the University of Sussex

该补助金支持苏塞克斯大学的一项滚动研究计划，主要有三个主题：* 宇宙学用WMAP卫星对宇宙微波背景辐射（CMBR）的观测对宇宙学模型，包括暴胀模型，产生了很大的限制。未来的实验将探测早期宇宙中引力波的产生。苏塞克斯一直并将继续处于这一领域的最前沿。混合膨胀模型在相变中结束，拓扑缺陷可以形成，包括字符串，纹理和半本地字符串。我们将预测它们对CMBR的影响。我们已经制定了一个严格的框架模型比较。我们将把它应用到暴胀模型，宇宙的再电离历史，调查设计等宇宙学中的一个关键问题是支配宇宙能量密度的暗能量的性质。我们将从理论上和使用暗能量巡天（DES），斯隆数字巡天（SDSS），UKIRT红外深空巡天（UKIDSS）和ESO VST和VISTA巡天的数据来探索这个问题。* 我们将结合联合收割机的大型观测和模拟集群调查，以提供强大的约束宇宙学和物理学的星系和集群的形成。苏塞克斯是XMM星团巡天（XCS）的领导者，该巡天有超过2000个星团候选者，预计将产生有史以来最大的同质星团样本，包括许多高红移的星团。星系团的演化和大尺度分布将对宇宙学模型提供强有力的约束。千年气体模拟是有史以来最大的星团流体动力学模拟，并提供了一个无与伦比的模拟星团目录与观测比较。各种各样的能量注入到星系团内和星系际介质的物理模型可以进行测试，包括超新星/星系形成和活动星系核。* 银河系我们是对形成中的星系进行大量深入调查的主要贡献者。其中最值得注意的是赫歇尔多层河外巡天（爱马仕），由6个不同深度和区域的独立巡天组成。宇宙中恒星发出的光大约有一半被尘埃吸收，并以远红外线重新辐射。爱马仕将提供对远红外星系群的遗产研究，并记录不同的红移、光度和环境对宇宙恒星形成历史的贡献。对估算可靠的光度红移至关重要的补充近红外数据将由UKIDSS DXS/UDS和VISTA VIDEO巡天提供。我们正在着手一项新的“混合建模”方案，利用从观测宇宙学借来的技术，将观测和星系形成的理论模型结合起来。我们将使用baidu参数估计和模型选择，通过直接与观测结果进行比较来约束模型，从而消除了对中间现象学模型（如光度函数）的需要。

This grant supports a rolling programme of research at the University of Sussex with 3 main themes: * Cosmology Observations of the cosmic microwave background radiation (CMBR) with the WMAP satellite have placed strong constraints on cosmological models, including those of inflation. Future experiments will probe gravitational wave production in the early universe. Sussex has been, and will continue to be, at the forefront of this field. Models of hybrid inflation end in phase transitions at which topological defects can form, including strings, textures and semi-local strings. We will make predictions for their effect on the CMBR. We have developed a rigorous framework for model comparisons. We will apply this to inflationary models, the reionisation history of the Universe, survey design, etc. One of the key questions in cosmology is the nature of the dark energy that dominates the energy density of the Universe. We will explore this question both theoretically and using data from the Dark Energy Survey (DES), Sloan Digital Sky Survey (SDSS), UKIRT Infrared Deep Sky Survey (UKIDSS) and ESO VST and VISTA surveys. * Clusters We will combine large observational and simulated cluster surveys to provide strong constraints on both cosmology and the physics of galaxy and cluster formation. Sussex is leading the XMM Cluster Survey (XCS) that has over 2000 cluster candidates and is expected to produce the largest ever homogeneous cluster sample, including many at high redshift. The evolution and large-scale distribution of clusters will provide strong constraints on cosmological models. The Millennium Gas simulations are the largest ever hydrodynamical simulations of clusters and provide an unrivalled catalogue of mock clusters for comparison with the observations. A variety of physical models for energy injection into the intracluster and intergalactic media can be tested, including supernovae/galaxy formation and active galactic nuclei. * Galaxies We are major contributors to a large number of deep surveys of forming galaxies. The most notable of these is the Herschel Multi-tiered Extragalactic Survey (HerMES) that consists of 6 separate surveys of different depths and areas. Roughly half the light emitted by stars in the Universe has been absorbed by dust and re-radiated in the far infra-red. HerMES will provide a legacy study of the far infra-red galaxy populations and characterise the contribution of different redshifts, luminosities and environments to the star-formation history of the Universe. Complementary near-infrared data, essential for estimating reliable photometric redshifts, will be provided by UKIDSS DXS/UDS and VISTA VIDEO surveys. We are embarking on a new programme of 'hybrid modelling' that combines observations and theoretical models of galaxy formation using techniques borrowed from observational cosmology. We will use bayesian parameter estimation and models selection to constrain the models by direct comparison with observations, eliminating the need for intermediate phenomenological models such as luminosity functions.