Charles Critchfield, a mathematical physicist with ordnance experience at the Army's Aberdeen Proving Ground, was in charge of the Target, Projectile and Source Group.
In 1950, with the aid of a cloud chamber that contained lead plates, Ney, together with Charles Critchfield and graduate student Sophie Oleksa, searched for primary cosmic ray electrons.
The initiator itself was designed by James L . Tuck, and its development and testing was carried out at Los Alamos National Laboratory in " Gadget " division's initiator group led by Charles Critchfield.