crookedindifference:

Louis Alexander Slotin (December 1, 1910 – May 30, 1946) was a Canadian physicist and chemist who took part in the Manhattan Project, the secret U.S. program during World War II that developed the atomic bomb. As part of the project, Slotin performed experiments with uranium and plutonium cores to determine their critical mass values. During World War II, Slotin continued his research at Los Alamos National Laboratory.

On May 21, 1946, Slotin accidentally began a fission reaction, which released a burst of hard radiation. He was rushed to a hospital, and died of radiation sickness nine days later on May 30, the second victim of a criticality accident in history. Slotin was hailed as a hero by the United States government for reacting quickly enough to prevent his accident from killing any colleagues. The accident and its aftermath have been dramatized in several fictional accounts.

Dr. Manhattan?