Paul Ulrich Villard
Paul Ulrich Villard was a French chemist and physicist. He discovered gamma rays in 1900 while studying the radiation emanating from radium.
Villard was born in SaintGermainauMontdOr, Rhne. He graduated from the cole Normale Suprieure in 1881 and taught in several Lyces, ending with a Lyce in Montpellier. He would maintain a laboratory position at the Ecole Normale Suprieure until his retirement. At the time when he discovered what we now call gamma rays, Villard was working in the chemistry department of the cole Normale Suprieure rue dUlm, Paris.
Source: Wikipedia