Persa Raymond "P. R." Bell

Oak Ridge scientist P. R. Bell advanced the art of scintillation spectrometry, using radioactive tracers scanned with a scintillator and collimator for medical diagnosis. Born in Fort Wayne, Indiana, in 1913, Bell attended Howard College and the University of Chicago, joining the scientists mobilized for World War II and contributing to development of improved radar systems at the Massachusetts Institute of Technology Radiation Laboratory from 1941 to 1946.

After the war Bell joined the physics group at Oak Ridge National Laboratory (ORNL), then moved into the thermonuclear group seeking to develop fusion energy sources. He led a scientific team at Oak Ridge that improved the scintillation spectrometer, an electronic device for detecting and recording small pulses of light (scintillations) emanating from phosphorescent substances when energized by radiation. This device had practical applications for the ORNL fusion research program and also for medical science, as it was modified for use as a scanner to locate brain tumors through the uptake of radioactive iodine, thereby permitting diagnosis without intrusive surgery. Subsequent modifications permitted use of the scanners for diagnosis of cancer and diseases of many internal organs, and the instruments became basic tools of modern medical science.