Becquerel

Becquerel may refer to Antoine-Henri Becquerel (1852–1908), a French physicist whose work helped establish the study of radioactivity, or to the becquerel, the SI unit of radioactivity named in his honor. He came from a family of scientists and conducted research on luminescence and phosphorescence before turning to radioactive phenomena.

In 1896, Becquerel investigated whether phosphorescent emission could be responsible for the glow observed in certain uranium-containing salts. He found that photographic plates were fogged even when the samples were sealed away from light, indicating that the emission originated from the material itself rather than from light-induced luminescence. This led to the discovery of spontaneous radioactivity, a property of certain elements to emit radiation without external energy.

For this groundbreaking work, Becquerel shared the 1903 Nobel Prize in Physics with Pierre and Marie Curie for their investigations into radioactivity and its properties. His experiments laid the foundation for a new understanding of atomic structure and nuclear physics, and spurred extensive research by the Curies and others.

The becquerel (Bq) is the SI unit of radioactivity named in his honor. It is defined as one disintegration per second and is a derived unit in the International System of Units. While the curie (Ci) remains widely used in some contexts, the becquerel provides a standardized measure of radioactive decay within SI.