Experimental Evidence for Electron Velocities as the Cause of Compton Line Breadth with the Multicrystal Spectrograph

The main purpose of this research was to test the correctness of the assumption that the initial velocities of electrons in the scattering body cause the observed breadth of the Compton shifted line. The test consists in observing the natural breadths of the Compton line for different scattering angles and primary wave-lengths and comparing these with the functional dependence of breadth on scattering angle and primary wave-length deduced theoretically on the basis of the assumption under test. It is shown in this paper that if electron velocities are the cause of the breadth then this breadth should increase with the scattering angle according to the approximate formula $\Delta \lambda =Kcos\frac{1}{2}\theta$ where $\Delta \lambda$ is the breadth, $\theta$ the scattering angle and $K$ a constant depending on the primary wave-length and the scattering substance. For the same scattering angle and substance the breadth should be proportional to the primary wave-length.