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#Mon Aug 09 11:51:55 CEST 2010
Text__u53l8KObEd-WfYQ0GneCwQ_title=X-Ray Light Particles Bounce Off Electrons
Text__u53l8KObEd-WfYQ0GneCwQ_text=<p>In the early 1920s, Arthur H. Compton investigates the spectrum of X-ray light scattered by graphite. In 1922 he finds a plausible explanation for the relationship between the angle of scatter and the wavelength of X-ray radiation\: The incident X-ray light quanta collide with electrons elastically, thereby giving off part of their energy. This is the first direct proof for the light-quantum hypothesis. Sommerfeld learns of this during a trip to the U.S. and informs Bohr by letter.</p>