Angular correlation measurement of emitted electrons from e-He collision using multi-dimensional coincidence method

The purpose of this研究项目consists in two parts；i) to develop a new data acquisition system which records a set of signals from two independenttwo-dimensional position sensitive detectors for a multiple coincidence analysis between them(2) to measure the angular correlation of two out-going electrons emitted in the ionizationprocess of He atom by electron impact.We developed a two-dimensional coincidence data acquisitionsystem several years ago. The system was successfully applied to several experiments. The newlydeveloped system applies to the 2-dimensional position sensitive detector (PSD). the架构已经改变了accordance with progress of PC平台being attained a multi-coincidenceexperiments.The main features of the system are as follows. Coincidence data acquisition between two2-dimensional PSDs. List mode method (time-sequential raw data storage method). Dynamic graphicmonitor function. PC平台（Windows NT） base. 20ns time resolution. High count rate capability（up to lOOkcps）.The list mode method was adopted in this system. The raw data from The detectors arefully recorded in a hard disk The data are analyzed and The spectrum in coincidence with Thesignals in appropriate regions of interest （ROD is simultaneously displayed.The experimental）apparatus which include一个电子枪，2-dimensional PSD etc已经建立，虽然它已经在coincidence measurement作为一个结果的分析experimental data,in order to obtain the information about the angular correlation of two outgoing electrons made intothe purpose at present, it turns out that the future experimental conditionsuch as removal of accidental coincidence, need to be improved。

The purpose of this research project consists in two parts ; i) to develop a new data acquisition system which records a set of signals from two independent two-dimensional position sensitive detectors for a multiple coincidence analysis between them, and ii) to measure the angular correlation of two out-going electrons emitted in the ionization process of He atom by electron impact.We developed a two-dimensional coincidence data acquisition system several years ago. The system was successfully applied to several experiments. The newly developed system applies to the 2-dimensional position sensitive detector (PSD). The architecture has been changed in accordance with progress of PC platform being attained a multi-coincidence experiments.The main features of the system are as follows.・Coincidence data acquisition between two 2-dimensional PSDs.・List mode method (time-sequential raw data storage method).・Dynamic graphic monitor function.・PC platform (Windows NT) base.・20ns time resolution.・High count rate capability (up to lOOkcps).The list mode method was adopted in this system. The raw data from the detectors are fully recorded in a hard disk. The data are analyzed and the spectrum in coincidence with the signals in appropriate regions of interest (ROD is simultaneously displayed.The experimental apparatus which include an electron gun, 2-dimensional PSD etc, has been constructed. Although it succeeded in coincidence measurement as a result of analyzing experimental data, in order to obtain the information about the angular correlation of two outgoing electrons made into the purpose at present, it turns out that the future experimental condition, such as removal of accidental coincidence, need to be improved.