SCANNER FOR AUTOMATED HIGH-PRECISION MEASUREMENTS OF WIRE POSITIONS IN WIRE CHAMBERS

We have developed a device to perform precise automated measurements o f the relative wire separations in a planar wire chamber. The measurem ent scheme involves slowly passing the wire chamber through a laser be am directed onto a photodiode. The measured position of the chamber as a function of time is then correlated with the photodiode response to yield the relative wire positions with a mean accuracy of better than 10 mu m (FWHM). The operational principles, system components, and re sults from our studies are discussed.