Development of Crystallographic Data Acquisition Systems for Biological and Chemical Research at the Advanced Photo Source

第三代同步辐射设备，如目前正在阿格尼国家实验室调试的先进光子源（APS），将成为世界上用于科学研究的主要x射线源。APS插入装置x射线源在中、硬x射线区域的光谱亮度和独特的光谱特性大大提高了现有科学前沿的可能性，更重要的是，开辟了新的研究领域。x射线光学技术的同步发展确保了与源的这些特性相平行的x射线光束可以被输送到样品中。然而，为了充分利用这些机会，必须进行类似的数据采集仪器开发。光源和光学的发展使研究人员能够更快地获取数据，检查更小（因此更容易获得）的晶体，并研究时间分辨的散射现象。结果，数据采集速率急剧增加，因此需要新的衍射仪和探测器系统。新的探测器，如新兴的基于ccd的系统，有可能满足新的需求。然而，只有将所有这些系统精心集成到专用的x射线实验站中，才能充分利用这些系统。我们建议开发集成的数据采集系统，包括快速可靠的衍射仪、优化的探测器和读出系统，以及可理解的仪器控制软件，使所有专业水平的研究人员都能专注于他们的实验，而不是系统的操作。将特别强调系统集成、设备保护和可靠性，因为昂贵的区域探测器在无意中暴露于高功率x射线光束时可能在几秒钟内被破坏。这些仪器在结构生物学和相关的化学领域有着共同的研究重点。数据采集系统由以下部分组成：-开发新型快速衍射仪，满足小样本研究的特殊需要，可容纳大型和重型探测器系统，以及必要的外围设备，如低温恒温器和单晶微光度计；-购置4个最先进的探测器，对它们进行优化，以便进行特定的实验，并对这些探测器进行表征，以消除伪象；-开发显示软件和图形用户界面，帮助研究人员实时评估初始温度和数据质量，从而在进行实验时做出明智的在线决策。APS和相关的x射线束线代表了来自许多资助机构的大量国家投资，即美国能源部、国家科学基金会、国家卫生研究院、伊利诺伊州、私人基金会和机构。芝加哥大学的研究工作是由高级辐射源联盟（CARS）组织的，该联盟由地球、土壤和环境科学（GSECARS）、生物科学（BioCARS）和化学与材料科学（ChemMatCARS）组成。建议的项目总成本估计为205万美元。其中一半资金是本提案所要求的，另一半资金将作为由澳大利亚核科学与技术组织（ANSTO）代表CARS向芝加哥大学提供的资金的非联邦匹配资金提供。

Third generation synchrotron radiation facilities, such as the Advanced Photon Source (APS) presently under commissioning at Argmnne National Laboratory, will be the world's leading sources of x-rays for scientific research. The greatly increased spectral brilliance and unique spectral properties of the APS insertion device x-ray sources in the intermediate and hard x-ray regions offer the possibility to significantly advance existing scientific frontiers and, more important, to open new research areas. The concurrent development of x-ray optics technology ensures that x-ray beams which parallel those properties of the source can be delivered to the sample. However, in order to take full advantage of these opportunities, similar development of data acquisition instrumentation must take place. Source and optics developments allow researchers to take their data faster, to examine much smaller (and hence more readily available) crystals, and to study time-resolved scattering phenomena. As a consequence the data acquisition rate has increased dramatically thus requiring novel diffractometer and detector systems. New detectors such as the emerging CCD-based systems have the potential to meet the new demands. However, all of these systems can only be used optimally if they are carefully integrated into dedicated x-ray experimental stations. We propose to develop integrated data acquisition systems, comprised of fast and reliable diffractometers, and optimized detectors and read-out systems with understandable instrument control software, that allow researchers at all level of expertise to focus on their experiments rather than operation of the system. Particular emphasis will be placed on system integration, equipment protection and reliability, since expensive area detectors can be ruined in seconds when inadvertently exposed to high-powered f x-ray beams. These instruments share a common research focus in structural biology ~\/ and related a reas of chemistry. The data acquisition systems are composed of: - development of novel fast diffractometers which address the particular need for research on small samples and which can accommodate large and heavy detector systems, and essential peripheral equipment such as cryostats and single crystal micro-photospectrometers; - acquisition of four state-of-the-art detectors, their optimization for particular experiments, and characterization of these detectors to eliminate artifacts; - development of display software and a graphical user interface, which aids researchers to assess initial cr~stal and data quality in real time and hence to make sensible on-line decisions in the conduct of their experiments. The APS and associated x-ray beamlines represent a large national investment from many funding agencies, namely the US Department of Energy, the National Science Foundation, the National Institutes of Health, the State of Illinois, private foundations and institutions. The research effort at The University of Chicago is organized in the Consortium of Advanced Radiation Sources (CARS), comprising the Geo-, Soil-, and Environmental Sciences (GSECARS), the Biological Sciences (BioCARS), and Chemistry and Material Sciences (ChemMatCARS). The proposed total project cost is estimated to be $ 2.05M. One half of the funding is requested in this proposal and the other half will be provided as a nonFederal match from funds granted by the Australian Nuclear Science and Technology Organization (ANSTO) to The University of Chicago acting for and on behalf of CARS.