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We introduce a new apparatus for measuring the outgassing rate of assemblies and functional units. Outgassing rates given in the literature, if available, are mostly insufficient to plan and set up a vacuum system, more so if commercial parts, preassembled items, or complex electronics with unknown components are deployed. Outgassing rates have a severe impact on the required pumping speed in ultrahigh vacuum systems and they change if the samples are powered or heated. The newly built apparatus uses the throughput method to measure outgassing rates. It can house probes with a size of 0.10 × 0.10 × 0.13 m 3 and supplies electrical currents of up to 5 A. In addition, a heater can establish temperatures of up to 200 ° C directly. A procedure is given to identify the main gas inputs and to retrieve data with a lower limit of 1.5 × 10 − 8 Pa m 3 s − 1 after 100 h in vacuum. In this paper, we present the experimental setup and first results for samples of polytetrafluorethylene, polyamide (PA6), Viton (1A), and oxygen-free high thermal conductivity copper at room temperature. [ABSTRACT FROM AUTHOR]

Several space missions, such as quantum optical experiments or quantum sensors, require ultrahigh vacuum (UHV) systems to perform their experiments and fulfill the scientific mission goals. Most of these experiments use standard ConFlat (CF) flanges for the design of the UHV system. One of the biggest challenges for these vacuum systems during a space mission is the mechanical loads. These loads are applied during launch, stage separation, etc., as a combination of static and dynamic loads. When loads are applied, the UHV system can experience an increased leakage rate, which decreases the vacuum quality. Investigation of the rise of the leakage rate due to static loads is an important step to allow a proper design process of space suitable UHV systems. In this paper, CF DN40 flange connections will be experimentally tested for standard aluminum (AluVaC) and stainless steel (316LN-ESR, 14429-ESU) tubes. Additionally, three different bolt pretension torques of 10, 12.5, and 15 N m are tested and compared. The presented results can be used to improve the design and assembly procedure for future UHV systems, such as the MAIUS (Matter-Wave Interferometry under Microgravity) sounding rocket missions. [ABSTRACT FROM AUTHOR]

Focuses on the launch of "PloS Biology" journal. Features of the scientific journal; Aim of the journal; Benefits of an open-access publication.