Atom bombardment ejects what appeared to be hydrogen nuclei. By 1920 he had accepted that the hydrogen nucleus is a distinct particle within the atom and named it proton. Neutrons have no electrical charge and have a free mass of 1,839 times the mass of the electron, or , the heaviest of the three constituent particles, but it can be reduced by the nuclear binding energy. Neutrons and protons (collectively known as nucleons) have comparable dimensions—on the order of —although the 'surface' of these particles is not sharply defined. The neutron was discovered in 1932 by the English physicist James Chadwick.
Split the Atom FabricLive.40 released in June 2008. Machine Gun has also been released as part of WipEout HD Fury's soundtrack and appeared in a trailer for the game Far Cry 3. Split the Atom received positive reviews from critics. Skiddle gave the album 4 out of 5 stars, saying "Split The Atom works to satisfy even the most fastidious of music fans." Sputnik Music reviewer Deviant gave the album a 4.5 out of 5 stars, saying "Split The Atom is poised to destroy the lives of clubbers worldwide and invade the senses of anyone brave enough to invest ample time in it."