X-Ray Systems

Applications
  • Electron Temperature Measurement
  • Impurity Studies
  • Tomographic Imaging
  • MHD Instability Investigations
  • Electron Distribution Function Diagnostics

Features

  • Si(Li) and Ge detectors available for spectroscopy
  • Flux detector arrays for tomographic applications
  • Custom geometry multiple detector assemblies designed to customer requirements
  • Excellent energy resolution as low as 2.5% at 5.9KeV [Si(Li), Ge] and 0.4% at 122 KeV
  • Ultra high vacuum compatible
  • High throughput for incident fluxes greater than 500 k/sec
  • NIM or CAMAC packages
  • Backed by years of research experience in the demanding fusion enviroment

Description

The spectroscopic systems are compact multiple detector solid state arrays. They are cooled to liquid nitrogen temperature by a cryogenic system featuring automatic level sensing and fill. Flux detectors are diffused junction detectors with integrated preamplifiers. For spectroscopy, preamplifiers matched to the detectors are integrated into the detector head. Shaping amplifiers, high voltage power supplies, and ADCs are available in NIM or CAMAC standard configurations.

Background

For over 25 years, General Atomics has been producing and using X-Ray systems for high temperature plasma diagnostics. Applications include measurement of electron temperature, determination of impurity concentrations, imaging, investigation of instabilities, and determination of the electron distribution function.

General Atomics operates the DIII-D tokamak for the U.S. Department of Energy. The DIII-D X-Ray System consists of a three-detector X-Ray spectrometer with variable geometry [2 Si(Li) and 1 Ge detector] and two 32-detector diffused junction arrays, plus three 24-detector detector diffused junction arrays for tomographic imaging. The three-detector spectroscopic array features a remotely controllable aperture and filter set and in-situ energy calibration. The spectroscopic electronics include pileup rejection, baseline restoration, and 1.7 microsecond conversion time.