Particle and radiation detectors end window beta G-M tubes book 2 part 2 Recommended Window Window Working Max.* Dead Time Type Diameter Thickness Voltage Background (approx.) No. (mm) (mg/em2) iv) {counts/min)} (us) 2P1400 9 2to3 500 10 90 2P1481 W7 2.5to3 430 30 120 ZP1480 7 2.5 to3 430 30 120 2P1420 7 15 to2 550 6. 150 +ZP1440 19.8 1.6 to 2 600 8 65 ZP1410 19.8 1.6to2 575 15 175 ZP1470 24.1 1.5 to 2.5 600 26 70 2P1430 27.8 15to2.5 575 25 190 +ZP1450 278 165 to2 625 18 60 ZP1460 51 3.5to4 900 45 45 *Shielded with 50mm lead and 3mm aluminium. tSmall quantities suitable for anticoincidence applications in conjunction with a guard tube may be available on request to Mullard Ltd. gamma sensitive G-M tubes Recommended Gamma Working Max, * Dead Time Type Sensitivity Voitage Background (approx.) No. {counts/min} (v) {counts/min) (us) 2P1210 6 s00t 430 40 200 2P1220 13 000f 430 75 210 Unshielded. PAt 1.0MR/h Radium source, 140