TWO NEW TYPES OF PHOTOELECTRON MULTIPLIERS FOR INVESTIGATIONS OF SHORT- LIVED PLASMAS

Two new types of photomultipliers, one battery-powered and the other powered by a low-current, high-voltsge cascade, are described. The resolution was improved with respect to other photomultipliers, and the susceptibility to noise considerably reduced. Since photomultiplier, highvoltage source, and tuning stage are well shielded in a relatively small housing, these devices are distinguished by simple and inexpensive construction, great stability, high sensitivity, and improved manageability. The low-current, high-voltage device is suitable for use in long measurement series in research installations with weak perturbance fields and for triggering. The battery-powered device cand be used for accurate measurements in strong interfering fields. (tr-auth)