Source of Excitation and X-ray Detection in PIXE Analysis

The high DC voltage on the terminal is produced by transferring to it a steady current of positive ions. The main parts of the accelerator are  

The negative ion beams from the ion source are injected into the pelletron accelerator at an energy of about 100 keV by the injector system. The two negative ion-sources are as given below  

SNICS (Source of Negative Ions hy Cesium Sputtering) 

In this ion source the cesium atoms used to cause sputtering, are ionized in an inert-gas discharge. The cathode containing a small amount of the material whose beam is to be produced, is inserted in the chamber through the air lock. The ionized cesium then sputters the solid cathode material to produce negative ions. This ion-source is used to produce the negative ions of almost all the solid materials. 

The negative ions from the ion sources are first preaccelerated and then guided to the accelerator entrance by injector magnet . The Einzel lens assembly preaccelerates the negative ions from the ion source and focuses the beam on to the image slit through the injector magnet. 

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