Horizontal dilution cryostat for polarized targets used in a high intensity photon beam

A horizontal continuous flow 3He-cryostat was modified to a dilution cryostat with special regard to fast cool-down and easy loading of the target material. This dilution cryostat, built for target asymmetry measurements with a photon beam, has a cooling power of 5 mW at 0.2K, 20 mW at 0.3 K and 34 mW at 0.4 K. The lowest temperature attained was 175 mK. Target asymmetry measurements of the reaction γd → pn at theta/sub CM//sup P/ = 1250 were performed using the external photon beam of the Bonn 2.5 GeV electron synchrotron. As target material the authors used D-butanol (C4D10O) with a maximum deuteron polarization of 27% in a magnetic field of 2.5T. Under the same conditions deuterons in D-ammonia (ND3) could be polarized up to 30%. 8 references, 3 figures