Antoine Henri Becquerel (; French: [ɑ̃twan ɑ̃ʁi bɛkʁɛl]; 15 December 1852 – 25 August 1908) was a French physicist and Nobel laureate in Physics for the discovery of radioactivity. The SI unit of radioactivity, the becquerel (Bq), is named after him.
Source : Wikipedia