Question: X-rays from an x-ray tube are Bragg reflected as shown in Fig. from the planes of a calcite crystal spaced 0.3036nm apart. Photons of wavelength λ = 0.3654nm emerge from the crystal at an angle α with respect to their initial direction (see Fig.) and are Compton scattered through an angle of 90 ? as they pass through a second material.
a. Find the angle α that the diffracted photon forms with its initial direction.
b. What is the minimum accelerating voltage that would produce a photon of the given wavelength?
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Fig. - Compton scattering arrangement
c. How much energy was lost by the photon, and where did the energy go?