The understanding of complex and/or large vacuum systems operating at cryogenic temperatures requires a specific knowledge of the vacuum science at such temperatures. At room temperature, molecules with a low binding energy to a surface are not pumped. However, at cryogenic temperatures, their sojourn time is significantly increased, thanks to the temperature reduction, which allow a "cryopumping". This lecture gives an introduction to the field of cryogenic vacuum, discussing surface desorption, sticking probability, thermal transpiration, adsorption isotherms, vapour pressure of usual gases, industrial surfaces and roughness factors. These aspects are illustrated with the case of the Large Hardon Collider explaining its beam screen and its cryosorber, leaks and beam vacuum system modelling in a cryogenic environment. Finally, operation of cryogenic beam vacuum systems is discussed for LHC and other cryogenic machines.
Environmental Stabilization of Perfect-Crystal Neutron Interferometry Using a Large Vacuum Chamber with Cryogenic Sample Access
North Carolina State University（北卡罗来纳州立大学）；University of Waterloo（滑铁卢大学）；Tulane University（杜兰大学）；National Institute of Standards and Technology（美国国家标准与技术研究院）；University at Buffalo（布法罗大学）
The vacuum and cryogenics system of the SOXS spectrograph
SOXS（Son Of X-Shooter）是一个由国际财团为ESO NTT望远镜建造的单目标摄谱仪。SOXS基于ESO-VLT的X-Shooter的传统，具有两个平行工作的臂（UV-VIS和NIR），分辨率狭缝积约为4500，能够在整个波段上同时观察从U到H波段的完整光谱范围。SOXS将对各种天文物体进行快速和长期的机会目标请求。SOXS真空和低温控制系统设计用于抽空、冷却和维持UV-VIS检测器和整个NIR光谱仪的工作温度。所选择的设计允许两个臂独立操作。本文介绍了低温真空控制系统的最终设计，其功能和在集成实验室进行的测试。
A centimeter-sized gas pressure sensor for high-vacuum measurements at cryogenic temperatures
Deutsches Elektronen-Synchrotron DESY（德国电子同步加速器研究所）；Universität Hamburg（汉堡大学）；Institut für Experimentalphysik, Universität Hamburg（汉堡大学实验物理研究所）；Institut für Quantenphysik (IQP) & Zentrum für Optische Quantentechnologien (ZOQ), Universität Hamburg（汉堡大学量子物理研究所与光学量子技术中心）；Fraunhofer-Institut für Siliziumtechnologie ISIT（弗劳恩霍夫硅技术研究所）
Cryogenic Ion Trapping Systems with Surface-Electrode Traps
我们提出了两个简单的低温射频离子阱系统，其中低温温度和超高真空压力可以在短短12小时内达到。离子阱在液氦浴低温恒温器或低振动闭合循环低温恒温器中操作。快速的周转时间和缓冲气体冷却的可用性使该系统成为测试表面电极离子阱的理想选择。发现闭合循环低温恒温器的振动振幅低于106nm。我们评估了系统通过加载表面电极离子阱与$^{88}$ Sr $^+$离子使用激光烧蚀，这是兼容的低温环境。使用多普勒冷却，我们观察到小的离子晶体中，光学分辨的离子具有超过2500分钟的捕获寿命。
3D-Structured Polyethylene Windows for Low-Loss Transmission in Wideband Cryogenic Terahertz Systems
Chalmers University of Technology（查尔姆斯理工大学）；Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS, Grenoble INP, CROMA（格勒诺布尔阿尔卑斯大学、萨瓦-蒙布朗大学、法国国家科学研究中心、格勒诺布尔理工学院、CROMA）
Direct stroke measurement of Piezos for cavity frequency tuner of the ILC prototype cryomodule using a Laser Displacement Sensor
High Energy Accelerator Research Organization（高能加速器研究机构）；The Graduate University for Advanced Studies, Department of Accelerator Science, School of High Energy Accelerator Science, High Energy Accelerator Research Organization (KEK)（高级研究院高能加速器科学学部加速器科学系）
Design and Performance of a Heated Gas Injector for Producing Cold Molecular Beams
Harvard/MIT Center for Ultracold Atoms（哈佛/麻省理工超冷原子中心）；Department of Physics, Harvard University（哈佛大学物理系）；Division of Engineering Science, University of Toronto（多伦多大学工程科学部）；Department of Physics, Massachusetts Institute of Technology（麻省理工学院物理系）
