Generation of X-rays:

In general, X-rays are generated either by X-ray tube or by synchrotron radiation [1]. The X-ray tube is the primary X-ray source used in laboratories, whereas the synchrotron radiation needs a large-scale accelerator for obtaining high-energy radiation.

Figure 2.02 shown below demonstrates the X-rays induced by colliding high-energy thermal electrons with a metallic target (water cooled) such as copper, molybdenum, etc., which can emit strong X-rays of 1.541 Å, 0.71 Å, respectively. The emission of different X-rays from the copper metal is also shown schematically in Figure 2.03.

Figure 2.02: Schematic diagram of a water cooled X-ray tube.

Figure 2.03: The characteristic X-rays are generated when the electron in the shells is flipped by high energy thermal electrons emitted from a filament.