DiRAC2.5 Operations: The DiRAC Project Office 2017-2020

天文学、核物理学和粒子物理学领域的物理学家都致力于从非常基本的层面上理解宇宙的运作方式。从原子核深处的大型强子对撞机实验探测到的最小距离，到在太空中发现的最大规模的星系团，他们工作的距离尺度相差50个数量级。然而，科学挑战通过以下问题联系在一起：宇宙是如何开始的，它是如何演变的？宇宙的基本组成和结构是什么？它们是如何相互作用的？要取得进展，不仅需要新的天文观测和实验数据，还需要新的理论见解。对理论的理解越来越多地来自大规模计算，这些计算使我们能够非常准确地用数据来面对我们理论的后果，或者允许我们详细询问数据，以提取对我们的理论产生影响的信息。这些计算测试了我们拥有的最快的计算机，并推动了该领域的技术界限。它们还为培训学生学习最先进的代码优化、数据挖掘和可视化技术提供了一个极好的环境。DIRAC-2.5项目建立在DIRAC HPC设施的成功基础上，并将提供所需的资源，以支持2017年由STFC支持的所有科学领域的尖端研究。除了现有的DIRAC-2服务外，从2017年4月开始，DIRAC-2.5将提供：1)达勒姆大学DIRAC超级计算机的计算能力增加2倍，该计算机专为需要大量计算机内存的模拟而设计。增强的系统将用于：(I)模拟产生引力波的黑洞对的合并，例如LIGO财团最近发现的那些；(Ii)对宇宙中星系的形成和演化进行迄今最真实的模拟；(Iii)对太阳内部和行星内部进行详细的模拟。2)剑桥大学一台新的高性能计算机，其特殊的体系结构非常适合于我们想要解决的理论问题，利用大量数据作为输入或在计算的中间阶段产生。我们将解决的两个关键挑战是：(I)通过分析来自欧洲航天局的Gaia卫星的新数据来提高我们对银河系的理解，以及(Ii)通过提高对涉及夸克物质基本成分的罕见过程的理论预测的准确性，提高欧洲核子研究中心大型强子对撞机实验发现新物理的可能性。3)在莱斯特的DiRAC Complex超级计算机上增加3500个计算核心，这将使其能够对宇宙中一些最复杂的物理情况进行模拟。这些研究包括：(I)星系团中恒星的形成--首次有可能跟踪质量比太阳大许多倍的恒星的形成；(Ii)气体对超大质量黑洞的吸积，这是从物质和驱动星系形成和演化的引擎中提取能量的最有效手段。4)一个由三名研究软件工程师组成的团队，他们将帮助DIRAC研究人员确保他们的科学代码，以从DIRAC星系团的硬件组件中提取可能的最佳性能。这些高技能的程序员将在2017年增加DIRAC设施的有效计算能力。

Physicists across the astronomy, nuclear and particle physics communities are focussed on understanding how the Universe works at a very fundamental level. The distance scales with which they work vary by 50 orders of magnitude from the smallest distances probed by experiments at the Large Hadron Collider, deep within the atomic nucleus, to the largest scale galaxy clusters discovered out in space. The Science challenges, however, are linked through questions such as: How did the Universe begin and how is it evolving? and What are the fundamental constituents and fabric of the Universe and how do they interact?Progress requires new astronomical observations and experimental data but also new theoretical insights. Theoretical understanding comes increasingly from large-scale computations that allow us to confront the consequences of our theories very accurately with the data or allow us to interrogate the data in detail to extract information that has impact on our theories. These computations test the fastest computers that we have and push the boundaries of technology in this sector. They also provide an excellent environment for training students in state-of-the-art techniques for code optimisation and data mining and visualisation. The DiRAC-2.5 project builds on the success of the DiRAC HPC facility and will provide the resources neededto support cutting edge research during 2017 in all areas of science supported by STFC.In addition to the existing DiRAC-2 services, from April 2017 DiRAC-2.5 will provide:1) A factor 2 increase in the computational power of the DiRAC supercomputer at the University of Durham, which is designed for simulations requiring large amounts of computer memory. The enhanced system will be used to:(i) simulate the merger of pairs of black holes which generate gravitational waves such as those recently discovered by the LIGO consortium;(ii) perform the most realistic simulations to date of the formation and evolution of galaxies in the Universe(iii) carry out detailed simulations of the interior of the sun and of planetary interiors.2) A new High Performance Computer at Cambridge whose particular architecture is well suited to the theoretical problems that we want to tackle that utilise large amounts of data, either as input or being generated at intermediate stages of our calculations. Two key challengesthat we will tackle are those of (i) improving our understanding of the Milky Way through analysis of new data from the European Space Agency's GAIA satellite and (ii) improving the potential of experiments at CERN's Large Hadron Collider for discoveryof new physics by increasing the accuracy of theoretical predictions for rare processes involving the fundamental constituents of matter known as quarks. 3) An additional 3500 compute cores on the DiRAC Complexity supercomputer at Leicester which will make it possible to carry out simulations of some of the most complex physical situation in the Universe. These include:(i) the formation of stars in clusters - for the first time it will be possible to follow the formation of stars many times more massive than the sun; (ii) the accretion of gas onto supermassive black holes, the most efficient means of extracting energy from matter and the enginewhich drives galaxy formation and evolution.4) A team of three research software engineers who will help DiRAC researchers to ensure their scientific codes to extractthe best possible performance from the hardware components of the DiRAC clusters. These highly skilled programmers willincrease the effective computational power of the DiRAC facility during 2017.