A new design for a target holder to produce stretched foils for recoil-distance (plunger) lifetime measurements is described. The foil tension is obtained by compression of an O-ring in contact with the foil, which is thereby stretched over an aluminum tube, one end of which has been optically polished. The new stretchers have been used in an actual measuremnt with the ANL plunger apparatus, and were found to be fully satisfactory. Using two gold foils, a minimum distance of 3 mu m before electrical contact has been obtained. The main advantage of the new holders is the ease and reliability with which good quality stretched foils can be produced. Using evaporated gold foils of about 2 mg/cm exp 2 thickness, a success rate of close to 100% can be achieved with a little practice. (ERA citation 09:012931)
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