A high-resolution X-ray detection system using STJ and SQUID amplifier

We succeeded in separating the STJ upper electrode events from other electrode events. This study is for X-ray spectroscopy of slow ions. With a SQUID amplifier, it is clearly seen that the upper electrode signal has a sharp peak with a narrow base, while the other has a relatively gentle peak with a wide base. The difference in signal width was used to separate the upper electrode events from other electrode events. Then the X-ray spectroscopy of slow highly charged ions was carried out at RIKEN. The results are shown here.