Liverpool John Moores University ARI Consolidated Grant 2021-2024

我们将利用观测和理论在天体物理学的前沿开展工作。ARI的使命是成为世界领先的研究中心，具有最高的国际卓越水平。我们的研究使用最先进的设备和数据分析技术。这种情况下的项目在技术上要求很高，需要PDRA和其他支持来帮助科学的传播。基于ARI在恒星形成（SF）方面世界领先的专业知识，我们将通过绘制三维恒星形成效率和研究星系中恒星形成与气体分布之间的联系来研究银河系中恒星形成与气体物理之间的联系。第二个项目将研究不同环境下的SF过程，特别是在早期宇宙中普遍存在的条件下，以评估行星系统作为环境和宇宙时代函数的生存概率。我们将通过将实际的质量损失率纳入其后期演化的计算，并在用于研究这些最后阶段的模型大气中建立风，来确定大质量恒星在死亡之前的样子。我们将解决一个主要的未解决的问题，即球状星团的形成机制，利用最近在这些系统中发现的多恒星群（主要来自ARI），为这个问题提供一个新的视角。球状星团也将用于一项单独的研究，以阐明其宿主星系的演化，使用嵌入在世界领先的宇宙学模拟中的详细星团形成物理学的独特组合。通过对银河系（MW）恒星的主要调查（APOGEE, Gaia-WEAVE）和宇宙学数值模拟（EAGLE）的联合分析，我们将解决卫星星系和原位SF对MW晕质量的贡献，从而揭示MW是否是一个典型星系的问题。其中两个计划涉及宇宙学问题。第一个是对长期存在的宇宙锂丰度问题的研究，这个问题将通过对大量金属贫乏的低红巨星分支恒星样本进行光谱分析来解决。第二个项目将使用一种基于非线性宇宙摄动理论的新型高效方法，研究大质量中微子对宇宙结构形成的影响。时域天体物理学一直是ARI研究的核心领域，由世界领先的2米机器人利物浦望远镜（LT）支撑。这个应用程序代表了这种活动的扩展，包括紧凑的物体合并和从新星到grb的所有恒星爆炸。该领域的一个理论建议是建立新星超级残留物的模型，其动机是ARI研究人员在M31中发现了这样的残留物。这项工作对新星种群研究和SNIa事件的途径具有启示意义。我们将计算不同质量、剥离程度和爆炸能量恒星的超新星爆炸模型的可观测特征，并将结果与观测结果进行比较。我们还将利用兹威基瞬态设备开发和利用第一个大型的、均匀选择的、光谱完整的光学瞬态样品。这将使我们能够研究各种形式恒星死亡的观测参数空间，并为LSST做好准备。研究引力波事件对应事件的后续计划将提供对致密物体合并的独特见解，将观测研究与这些事件特征的新模型的发展相结合。这些活动充分利用了ARI在该领域的专业知识，并利用我们对SN探测调查ZTF的特权；LIGO-Virgo EM后续实验，Swift GRB卫星以及包括LT在内的一系列领先天文设施的观测。

We will carry out work at the forefront of astrophysics using both observations and theory. The ARI's mission is to be a world-leading research centre at the highest international level of excellence. Our research uses the most advanced facilities and data analysis techniques. The projects in this case are technically demanding and require PDRA and other support to aid the delivery of the science. Building on ARI's world-leading expertise in star formation (SF), we will investigate the connection between SF and gas physics in the Milky Way by mapping the SF efficiency in 3-D and studying the connection between SF and the gas distribution in the Galaxy. A second project will look at SF processes in different environments, and particularly in the conditions prevailing in the early Universe, to assess the survival probabilities of planetary systems as a function of environment and cosmological epoch.We will determine how massive stars appear just before they die, by incorporating realistic mass-loss rates into calculations of their late-stage evolution, and building winds into the model atmospheres used to study these final phases.We will address a major unsolved problem, the formation mechanism of globular clusters, using the recent discovery of multiple stellar populations in these systems (driven largely from ARI) to give a new perspective on this question. Globular clusters will also be used in a separate study to shed light on the evolution of their host galaxies, using a unique combination of detailed cluster formation physics embedded in world-leading cosmological simulations.Through a joint analysis of major surveys of Milky Way (MW) stars (APOGEE, Gaia-WEAVE) and cosmological numerical simulations (EAGLE), we will address the contribution of satellite galaxies and in situ SF to the mass to the MW halo, and hence shed new light on the question of whether the MW is a typical galaxy.Two of the proposed projects address cosmological questions. The first is a study of the long-lasting problem of the cosmological lithium abundance, which will be tackled through spectroscopic analysis of a large sample of metal-poor lower red giant branch stars. The second will look at the impact of massive neutrinos on cosmological structure formation, using a novel and highly efficient method based on non-linear cosmological perturbation theory.Time-domain astrophysics has always been a core area of ARI research, underpinned by the world-leading 2-metre robotic Liverpool Telescope (LT). This application represents a broadening of this activity, encompassing compact object mergers and the full range of stellar explosions, from novae to GRBs. The one theoretical proposal in this area concerns modelling of nova super-remnants, motivated by the discovery of such a remnant in M31 by ARI researchers. This work has implications for nova population studies and pathways to SNIa events. We will compute the observable characteristics of supernova explosion models ofstars with different masses, degrees of stripping and explosion energies, and compare the outcomes with observations. We will also develop and exploit the first large, uniformly-selected, spectroscopically-complete sample of optical transients using the Zwicky Transient Facility. This will allow us to study the observational parameter space of all forms of stellar death and prepare for LSST.A follow-up programme studying counterparts to gravitational wave events will provide a unique insight into the mergers of compact objects, combining observational studies with the development of new models for the characterisation of these events. These activities capitalise on ARI's expertise in this field and exploit our privileged access to the SN detection survey ZTF; LIGO-Virgo EM follow-up experiments, the Swift GRB satellite and observations on a range of leading astronomical facilities including the LT.