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?-rays, X-ray Tube and X-ray Circuit ?A photon of EMR with energy of 59.3 keV would fall well within the ?X-ray region of the electromagnetic spectrum and would be known as ?a 'K-alpha emission'.For tungsten K-shell emission, it givesIn ?such a case, the energy of the emission arising from the interaction ?would equal the difference in binding energies between the K-orbital ?electron (69.5 keV) and the M-orbital electron (2.5 keV), i.e. approxi- ?mately 67 keV.?It should be clear at this stage that irrespective of the energy of the ?incoming electron, provided that energy is greater than the binding ?energy of the shell-bound electron, removal of that electron will always ?lead to the production of X-rays which fall into well-defined energy ?bands.More to the ?point, useful X-rays can be produced using this process, providing the ?target material has a high enough atomic number and the tube voltage ?is above 70 KeV.Wherever a K-alpha series of characteristic ?radiations is produced in tungsten, there will always be an L-series ?of emissions and an M-series of emissions (through to the last shell).This emission would be known as a K-beta X-ray ?photon.?2.?3.

‏-rays, X-ray Tube and X-ray Circuit
‏A photon of EMR with energy of 59.3 keV would fall well within the
‏X-ray region of the electromagnetic spectrum and would be known as
‏a ‘K-alpha emission’.
‏It is entirely possible that the vacancy in the K-orbital in the example
‏above could be filled with an electron arising from the M-orbital. In
‏such a case, the energy of the emission arising from the interaction
‏would equal the difference in binding energies between the K-orbital
‏electron (69.5 keV) and the M-orbital electron (2.5 keV), i.e. approxi-
‏mately 67 keV. This emission would be known as a K-beta X-ray
‏photon.
‏It should be clear at this stage that irrespective of the energy of the
‏incoming electron, provided that energy is greater than the binding
‏energy of the shell-bound electron, removal of that electron will always
‏lead to the production of X-rays which fall into well-defined energy
‏bands. These radiations are characteristic of the material in which they
‏are produced and their energy bands depend on three variables:
‏1. The atom type, i.e. the atomic number of the material which, in
‏turn, determines the binding energies of the shells.
‏2. The shell from which the electron was ejected (e.g. K, L, M) for
‏any given atom.
‏3. To a lesser extent, the shell from which the ‘replacement’ elec-
‏tron comes.
‏Characteristic line spectra are always produced by this process along-
‏side the continuous spectra, as demonstrated in Figure 4.7. From an
‏analysis point of view, the identity of every material can be determined
‏by identifying its emission spectra (X-ray spectroscopy). More to the
‏point, useful X-rays can be produced using this process, providing the
‏target material has a high enough atomic number and the tube voltage
‏is above 70 KeV.
‏It should be noted that characteristic radiation in any inner shell will
‏not be produced alone. Wherever a K-alpha series of characteristic
‏radiations is produced in tungsten, there will always be an L-series
‏of emissions and an M-series of emissions (through to the last shell).
‏The process works on a cascade basis, so that any gaps which appear
‏in any shell are filled immediately to maintain the orbital stability of
‏the atom.
‏A beam from characteristic X-ray production is called a homogenous
‏beam. For tungsten K-shell emission, it gives