Design of the characteristic impedance and trial manufacturing of the solenoid electrode structure for a position-sensitive fission counter

Solenoid electrode structures (SEST) and their electric characteristics were studied to develop a position-sensitive fission counter (PSFC) with a transmission delay line structure. The PSFC structure as a pulse transmission line consists of an anode with a solenoid structure, a cylindrical cathode and two output connectors. The time intervals of signal pulses from both connectors of the PSFC provide position information of detected neutrons. Design of the SEST and calculation of the characteristic impedance were carried out for investigations of the electric characteristics. The inductance and capacitance of the SEST were fixed to optimum values, respectively, so as to give a suitable characteristic impedance and sufficient pulse propagation time. A mockup of the SEST of which outer diameter and electrode length were 22 and 800mm, respectively, was manufactured to confirm the performance. The designed values of the SEST were verified by comparing the measured results with the calculation results. It was confirmed that the SEST fits to the PSFC. (author)