First section of FAIR ring accelerator SIS100 under vacuum
Another significant step has been achieved in the commissioning of FAIR, based at AVA partner’s GSI site. For the first time, the beam pipe of a section of the FAIR ring accelerator SIS100, operating at room temperature, has been pumped down to a high vacuum level (approx. 10-8 mbar). The commissioning of the vacuum systems serves the recording and analysing of pump-down curves, as well as tests of the functionality of valves, pumps and vacuum gauges and the execution of leak checks.
In recent weeks, the first three room temperature cells of the straight ring section have been installed into the tunnel by teams from the department “Transport & Installation” and handed over to the vacuum testing after completion. The vacuum segments are about eight meters long and consist of acceleration cavities, a first-turn diagnostic chamber, standard pumping chambers and several tubes, bellows and adapter flanges.
As the main accelerator of the new FAIR complex, the superconducting heavy ion synchrotron SIS100, which is currently under installation, operates in an underground tunnel about 17 meters below ground and has a circumference of about one kilometre. The machine consists of alternating segments operating at room temperature or at cryogenic temperature (liquid helium at -269°C).
Following the successful vacuum acceptance tests on this SIS100 section, work will continue in other room-temperature sectors.
This news article is based on original news article published on the GSI/FAIR website here:
https://www.gsi.de/en/start/news/details/2025/06/12/1st-vacuum-sis100