-- EstherBabetteMenz - 2021-04-29

Vacuum at the CRYRING@ESR Particle Detectors

There are currently several particle detector setups in operation at CRYRING@ESR, located downstream from the ElectronCooler (YR03) and the experimental section (YR09). They are used to detect product ions that have undergone a change in their charge state.

At the electron cooler, the YAP:Ce scintillation detector (YR03DS1HA) sits directly behind the first dipole magnet and is used to detect light ions in low charge states (including neutral reaction products). The CEM detector (YR04DS2HA) is located further down the straight section (YR04) and is used for heavier, highly charged ions (up to and including He-like uranium). Both detectors are used in recombination experiments at the electron cooler, including dielectronic recombination measurements.

All detectors have self-contained vacuum chambers that can be closed of from the main ring vacuum while the detectors are not in use or to facilitate easy replacement of components (e.g. scintillation crystals).

Vacuum Read-out

A simple vacuum read-out of the experimental installations around the ring can be found here. A more interactive display is available here.

YR03DS1HA is the scintillation detector behind the electron cooler and YR04DS2HA is the CEM detector. Both should be in the range of 10^-11 mbar during operation. The vacuum read-out should be closely watched while the pneumatic drive is operated in automatic mode.

A more interactive display of the vacuum pressure can be found in Grafana.

Closing the valves

Important: Before closing the valves make sure that the detector arm is fully retracted to the outside position of the step motor (not the pneumatic drive). Closing the valve while the detector is in the way will lead to substantial damage and further vacuum leaks. Instruction for stopping the pneumatic drive and driving to the outside positon with the step motor can be found here.

Close the valve using the hand wheel until fully closed. The resistance becomes noticeably bigger during the last few rotations, be sure to keep going until the end position is reached.