Design and performance of a laboratory based source of characteristic X-rays

Abstract

A theoretical description for the production of characteristic X-rays (CX) is reviewed highlighting features that enhance the CX intensity. These are incorporated into the design of a secondary target system for excitation by white radiation produced by an industrial X-ray tube; Philips MCN-166, capable of continuous operation at up to 160 kVp and 1.6 kW. Results are presented for the measured spatial profile, CX intensity at 8–75 keV and spectral purity as a function of accelerating voltage. The beam is a narrow fan with half height (horizontal by vertical) 200 mm by 50 mm at 1 m from the source. The beam intensity is presented in units ph/s/mm 2 at 1 m per kW and is equivalent to an isotope source with activities 100–300 mCi per kW deposited in the anode. The source provides variable intensity and the ability to change energy by simply exchanging the target material.