Author/Authors :
Kri?an، نويسنده , , P and Korpar، نويسنده , , Joze Staric، نويسنده , , M and Stanovnik، نويسنده , , A and Cindro، نويسنده , , M and ?krk، نويسنده , , D and Zavrtanik، نويسنده , , M and Hamacher، نويسنده , , T and Michel، نويسنده , , E، نويسنده ,
Abstract :
The relative quantum efficiency of several CsI photocathodes in an asymmetric multiwire proportional chamber has been measured. The photocathode surface of 24 × 24 cm2 is divided into 7.5 × 7.5 mm2 pads and the chamber is operated with methane at normal temperature and pressure and a gas gain of about 105. During tests of the high rate performance (∼2 MHz/cm2) of a smaller chamber (5 × 5 cm2), an interesting time variation of the count rate has been observed when illuminating the chamber with constant UV light.