What to the characteristic X-ray radiation? What is the origin? Solution - Characteristics x- ray radiations are emitted from heavy elements when their electrons make transitions between the lower atomic energy levels. - the high energy electron can also cause an electron close to the neclues in a metal atom to be knocked out from its place ORIGIN Discovery. German physicist Wilhelm Röntgen is usually credited as the discoverer of x rays in 1895, because he was the first to systematically study them, though he is not the first to have observed their effects. Rountgen called them x rays after the mathematical symbol X for unknown.