Target loop:
This target is designed as a "Basel-Loop" target. The liquid Hydrogen/Deuterium is moved by a fan ("Ventilator") in a closed loop. By this the heat of the energy deposition by the electron beam (up to 40 µA!) is continously moved to the heat exchanger ("Wärmetauscher").
The heat exchanger is cooled by a Philips cryo generator with a power of approx. 60 W.
To avoid density fluctuations the beam is moved by a fast wobbler across the target cell. This is done with an amplitude of 6 mm in horizontal and vertical direction at an frequency of several kHz. The actual position information is added to the event information in the data stream.
Target cell:
The target cell has a length of 48 mm and a width of 10 mm. The geometry is choosen to maximize the luminosity by a long target cell and to minimize the uncertainty by energy loss.
With this target cell we are able to reach luminosities of up to 50 MHz/µbarn (= 5·1037 s-1cm-2).
Schematic view of the completed cryo system:
