Introduction of PIXE analysis system in NIRS

In March 1999, electrostatic accelerator, Tandetron (Model 4117MC, High Voltage Engineering Europe Co.) was installed in the Electrostatic Accelerator Building for PIXE (Particle Induced X-ray Emission) analysis. The accelerating voltage is 0.4 to 1.7MV, and the maximum beam current is 5μA at 3.4MeV. This system has three beam ports for different types of PIXE analysis: normal, micro-beam and in-air. The first beam port is used for normal PIXE. Since two types of X-ray detecting device, Si (Li) and CdZnTe detectors, are available here, elements from Na (Z=11) to U (Z=92) are detectable. Fifteen samples can semi automatically be measured at one time using a proton beam of optical beam size from 0.5 to 2.0 mm at 100 nA beam current. A quadrupole triplet magnet (Model OM2000, Oxford Micro beams, Ltd.) attached to the second beam port produces a proton micro-beam of square shape less than 1μm×1μm. Micro-beam scanning PIXE analysis is carried out with this beam at 50pA current and scanning area up to 2.0mm square. The in-air PIXE analysis is performed using the third beam port. The operation of this machine has been scheduled to start from April 2000 and is controlled by Division of Technology and Safety. Some results preliminarily obtained are also shorn.