Replacement monochromator cryocoolers for NE-CAT

项目摘要 东北协作访问团队（NE-CAT）操作两个波荡器束线（24-ID-24）。 C和24-ID-E）在高级光子源。两条光束线均配备MD 2 微衍射仪、低温冷却系统、样品自动计数器和像素阵列检测器。 向拥有546个唯一用户的大型用户社区提供访问权限，执行657个数据 2021日历年的收集行程（3003次用户访问）。NE-CAT光束线收集 数据产生约180出版物和超过400 PDB存款每年。 两种NE-CAT光束线都采用FMB Oxford液氮制冷机来保持 在90 K的操作温度下，它们的硅单色晶体的温度。的 当前的低温冷却器是在束线最初建造时安装的， 大约15岁在多年的服务中，FMB牛津制冷机 可靠，只需要对控制系统进行日常维护和小修 系统.预计其最终失效，并减少梁振动，我们建议 用FMB Oxford Cryocooler XV系统更换两台低温冷却器。FMB Oxford低温冷却器 XV是一个经过验证的设计，将提供多年的可靠服务，同时也提高 通过减少硅单色器的液氮流引起的振动的束稳定性 晶体

Project Summary The Northeast Collaborative Access Team (NE-CAT) operates two undulator beamlines (24-ID- C and 24-ID-E) at the Advanced Photon Source. Both beamlines are equipped with MD2 microdiffractometers, cryocooling systems, sample automounters, and pixel array detectors. Access is provided to a large user community with 546 unique users performing 657 data collection trips in calendar year 2021 (3003 total user visits). The NE-CAT beamlines collect data resulting in approximately 180 publications and over 400 PDB deposits per year. Both NE-CAT beamlines employ FMB Oxford liquid nitrogen cryocoolers to maintain the temperature of their silicon monochromator crystals at an operational temperature of 90 K. The current cryocoolers were installed when the beamlines were originally constructed and are now approximately 15 years old. Over their many years of service, the FMB Oxford cryocoolers have been dependable and only required routine maintenance and minor repairs to their control systems. Anticipating their eventual failure and to reduce beam vibrations, we propose to replace both cryocoolers with FMB Oxford Cryocooler XV systems. The FMB Oxford Cryocooler XV is a proven design that will provide many years of dependable service while also improving beam stability by reducing liquid nitrogen flow-induced vibrations of the silicon monochromator crystals.