Pages: 209-213

Authors: Tayeb Kakavand, Mohammad M. Nasseri, Bahador Sharifi, Rohallah Razavi

Abstract

Preliminary measurements in a proportional counter with two independently counting wires have shown that counting rates up to 10⁶₂ counts/s per wire can be reached without critical loss in the “true versus measured” linearity relation. In this paper, a gas-flow multiwire proportional counter designed and constructed in Iran, is presented. Results obtained with a fabricated detector, containing 32 Ni-chromic anode wires, are shown. Each wire is associated with a fast pre-amplifier and a discriminator channel. Counting rates of over 10⁷ events per second are measured. The diameter, length, and resistance per unit length of anode wires are 35 µm, 3 cm and 10 Ω/m, respectively. The  cathode is constructed  of  two  fiber  glass  printed  sheets  of 4x12cm² dimensions. In this detector, P₁₀ gas (10% of methane and 90% of argon) is used. The volume of the detector sensitive area is 24 cm³. Detector signals are analyzed carefully through data acquisition systems (MCA, amplifier and preamplifier). Our study indicates that the present detector is a position sensitive detector and that the obtained position sensitivity resolution of this instrument is 3.5 mm.

 

 

 

Key words: proportional counter, position sensitivity, ionization, gas multiplication, charge division

FULL PAPER IN PDF FORMAT ( 858 KB)