Charles Christian Lauritsen (4.04.1892—13.04.1968) was an American physicist and a member of the National Academy of Sciences (1941). He was born in Holstebro (Denmark). In 1911 he moved to the USA. From 1930 he worked at the California Institute of Technology (professor in 1935-62).
His research was in the field of electron emission, X-rays, radiology, accelerator technology and nuclear physics. He studied electron emission from metals in strong electric fields, and he designed a number of high-voltage X-ray tubes and used them to accelerate charged particles. He was one of the first to obtain radioactive isotopes and powerful sources of neutrons by means of accelerators, discovering the (d, n) and (p, n) nuclear reactions. He studied the transmutation of light nuclei and nuclear structures, and discovered mirror nuclei. He designed an electrostatic analyser and a number of magnetic spectrometers. He detected (1941) internal conversion with the formation of electron–positron pairs.