Improvements of time-of-flight detector utilizing a thin foil and crossed static electric and magnetic fields*

Abstract We developed a time-of-flight (TOF) detector with a thin foil for mass measurements of unstable nuclei using the Rare-RI Ring at the RIKEN RI beam factory. Compared to the previous design, the developed TOF detector employed modified electrodes, and its static electric and magnetic fields were reduced. We improved the detection efficiency and stability of operation. Its specification and design were finally fixed for mass measurements. We also developed a position-sensitive detector based on the principles of the TOF detector. This study utilized larger microchannel plate (MCP) detectors than those of the prototype. By improving acceptance, we demonstrated the performance of the position-sensitive detector with very low material thickness.