The curie is a unit of ionizing radiation (radioactivity), symbolized Ci and equal to 3.7 x 10 10 disintegrations or nuclear transformations per second. This is approximately the amount of radioactivity emitted by one gram (1 g) of radium-226.
The unit is named after Pierre Curie, a French physicist. It was superseded by the becquerel (Bq) in 1981. The curie is a relatively large unit. To convert curies to becquerels, multiply by 3.7 x 10^10. Conversely, divide by 3.7 x 10^10 to convert becquerels to curies.