Application of position sensitive detector for the electron detachment cross-sections measurement

In this paper, we report our improved detection system based on a micro-channel plate (MCP) position sensitive detector, which could simplify our experiment process of the electron detachment cross-sections measurement in negative ion-gas collisions. The operating parameters of MCP are investigated thoroughly, and we present the dependence of the pulse height distributions (PHD) of the anode signals on MCP bias voltage, incident beam energy, incident beam intensity, and incident ion species. The optimum parameters, such as bias voltage of the MCP, the threshold of the electronics and incident ions intensity, are determined. The saturation curve of MCP is also shown. Finally, we give the single electron detachment cross-sections of H− and C− in collision with N2 obtained using the new position sensitive detection system. Consistency with other available experiment results shows the reliability of the new detection system.