i think 1956 but not sure
James Chadwick used a series of experiments involving alpha particles and beryllium to discover neutrons in 1932. By observing the scattering of these particles, he was able to infer the existence of neutrons, which are electrically neutral particles found in the nucleus of atoms.
Rutherford discovered that almost entire mass of an atom is located in the nucleus, and then, the neutron was discovered by Chadwick.
Sir James Chadwick discovered it in 1932
He Began He Reasearch In 1803 But Did Not Find His Answer Untill 1832 .
James Chadwick discovered the neutron in 1932.
That sounds like the neutron.
James Chadwick is the scientist credited with the discovery of neutrons in 1932. He conducted experiments that led to the identification of the neutron as a fundamental particle found in the nucleus of atoms.
The neutron was discovered by James Chadwick in 1932.
neutrons! see: 2nd paragraph Chadwick's experiment to discover the neutronshttp://library.thinkquest.org/C001124/gather/aexp.html
James Chadwick used a cloud chamber and a polonium-beryllium source in his experiments to discover the neutron, which ultimately led to the discovery of the atomic nucleus. His work provided crucial evidence for the existence of neutrons, which are neutral particles found in the atomic nucleus.
James Chadwick discovered the neutron, a subatomic particle that is found in the nucleus of an atom. He made this discovery in 1932, building upon the work of previous scientists in the field of atomic theory.
the paticle that was hard to detect was neutrons because it had no electrical charge.