Charles Lauritsen: Splitting Atoms and Studying Radiation

After hearing a physics lecture by Robert A. Millikan in St. Louis in 1926, 34-year-old Charles Lauritsen moved to Pasadena to enroll as a graduate student at Caltech. He received his PhD in 1929 for his work on high-energy X-rays, which led to his involvement in building high-voltage X-ray tubes for research in both medicine and physics. Ultimately, those tubes and Lauritsen's work with Millikan on treating cancer with X-rays attracted the attention of W. K. Kellogg, who funded the building of the W. K. Kellogg Radiation Laboratory in 1931 (it opened in 1932). Soon thereafter, Lauritsen modified one of Kellogg's high-voltage tubes to allow it to accelerate ions and split nuclei, a move that launched the field of nuclear physics at Caltech. Lauritsen's laboratory became the first to produce high-energy gamma rays, neutrons, and radioactivity with accelerators—one among his many key discoveries in the field. He went on to direct research in Caltech's Sloan and Kellogg Laboratories for over 30 years before his death in 1968 at the age of 76.