Effects of cathode material and water vapor on aging in straw tubes

Summary form only given. The aging effects due to radiation in straw tubes have been studied with small amounts of water vapor added to the gas stream. Two gases were investigated: argon/ethane (50/50) and CF/sub 4//isobutane (80/20). The effect on aging of cathode material has been investigated for four materials: aluminum, copper, gold, and nickel. Aging tests have been studied for straw tubes made from three different combinations of wall materials: Mylar, Kapton, and polycarbonate, using polyethylene or polyester as the adhesive between two layers of wall material.<>