A method to use drift chambers as track detectors for heavy ions

Abstract

A drift chamber with 15 cm drift space has been exposed to the heavy ion beam at Berkeley, USA. Such a chamber will be used in a proposed cosmic ray isotope experiment. From these tests we conclude that amplitude discrimination against δ-rays which accompany the heavy ions is possible. It is recommended to run the chamber at a relatively low sense wire voltage (in our case below 1300 V) in order to avoid space charge effects. This technique works without loss of detection efficiency for particles with Z > 10, for lower charges the losses increase.