Photoelectric effect inverse

The short-wavelength limit of the continuous spectrum is clearly a quantum phenomenon. X-ray generation by electron bombardment in principle resembles cathodoluminescence, and both processes are inverse photoelectric effects. The short-wavelength limit, Xq, discovered by Duane and Hunt6 obeys the relationship... 

This process of creation of photons from the energy of fast-moving electrons is called the inverse photoelectric effect. 

In his ground-breaking paper on the photoelectric effect (Sect. 1.6), Einstein [15] noted that if light consists of discrete particles ( photons in today s vernacular), then each such particle should have a momentum that is inversely proportional to the wavelength (2). This relationship follows from the theory of relativity, which requires that a particle with energy E and velocity w have momentum Ewfc. A photon with energy hv and velocity c should, therefore, have momentum... 

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