Natalia Krawczyk, Jacek Kaczmarczyk, Monika Kubkowska and Leszek Ryć
The paper presents comparison of two silicon drift detectors (SDD), one made by Amptek, USA, and the second one by PNDetector, Germany, which are considered for a soft X-ray diagnostic system for W7-X. The sensitive area of the first one is 7 mm2 × 450 μm and the second one is 10 mm2 × 450 μm. The first detector is cooled by a double-stage Peltier element, while the second detector is cooled by single-stage Peltier element. Each one is equipped with a field-effect transistor (FET). In the detector from Amptek, the FET is mounted separately, while in the detector from PNDetector, the FET is integrated on the chip. The nominal energy resolution given by the producers of the first and the second one is 136 eV@5.9 keV (at -50°C) and 132 eV@5.9 keV (at -20°C), respectively. Owing to many advantages, the investigated detectors are good candidates for soft X-ray measurements in magnetic confinement devices. They are suitable for soft X-ray diagnostics, like the pulse height analysis (PHA) system for the stellarator Wendelstein 7-X, which has been developed and manufactured at the Institute of Plasma Physics and Laser Microfusion (IPPLM), Warsaw, in collaboration with the Max Planck Institute for Plasma Physics (IPP), Greifswald. The diagnostic is important for the measurements of plasma electron temperature, impurities content, and possible suprathermal tails in the spectra. In order to choose the best type of detector, analysis of technical parameters and laboratory tests were done. Detailed studies show that the most suitable detector for the PHA diagnostics is the PNDetector.
Hannele Niiniviita, Jarmo Kulmala, Tuukka Pölönen, Heli Määttänen, Hannu Järvinen and Eeva Salminen
with different waist circumferences compared to a non-AEC device.
Patients and methods
The LightSpeed 16 (GE, Wisconsin, United States) and Plus 4 (Siemens, Erlangen, Germany) devices are third-generation CT scanners and they allow helical scanning. The LightSpeed 16 is a multi-slice CT with an adaptive array detector consisting of 24 parallel rows of solid-statedetectors. The detectors cover 20 mm in the z-direction at the iso-center. Detectors allow imaging of 16 slices per rotation and 0.63 to 10 mm slices can be reconstructed in the helical mode