[PAR] [TLE] James Chadwick [SEP] Sir James Chadwick, {'1': ", '2': ", '3': ", '4': "} (20 October 1891 – 24 July 1974) was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932.  In 1941, he wrote the final draft of the MAUD Report, which inspired the U.S. government to begin serious atomic bomb research efforts.  He was the head of the British team that worked on the Manhattan Project during the Second World War.  He was knighted in England in 1945 for his achievements in physics. [PAR] [TLE] Discovery of the neutron [SEP] The story of the discovery of the neutron and its properties is central to the extraordinary developments in atomic physics that occurred in the first half of the 20th century.  Early in the century, Ernest Rutherford developed a crude model for the atom, based on the gold foil experiment of Hans Geiger and Ernest Marsden.  In this model, atoms had their mass and positive charge concentrated in a very small nucleus.  Throughout the 1920s, the nucleus was viewed as composed of combinations of protons and electrons, the two elementary particles known at the time, but that model presented several experimental and theoretical contradictions.  The essential nature of the atomic nucleus was established with the discovery of the neutron by James Chadwick in 1932 and the determination that it was a new elementary particle, distinct from the proton.  Both the proton and neutron were presumed to be elementary particles until the 1960s when they were determined to be composite particles built from quarks.
[PAR] [TLE] James Chadwick [ SEP ] Sir James Chadwick , { ' 1 ' : " , ' 2 ' : " , ' 3 ' : " , ' 4 ' : " } ( 20 October 1891 – 24 July 1974 ) was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932 . In 1941 , he wrote the final draft of the MAUD Report , which inspired the U.S. government to begin serious atomic bomb research efforts . He was the head of the British team that worked on the Manhattan Project during the Second World War . He was knighted in England in 1945 for his achievements in physics . [PAR] [TLE] Discovery of the neutron [ SEP ] The story of the discovery of the neutron and its properties is central to the extraordinary developments in atomic physics that occurred in the first half of the 20th century . Early in the century , Ernest Rutherford developed a crude model for the atom , based on the gold foil experiment of Hans Geiger and Ernest Marsden . In this model , atoms had their mass and positive charge concentrated in a very small nucleus . Throughout the 1920s , the nucleus was viewed as composed of combinations of protons and electrons , the two elementary particles known at the time , but that model presented several experimental and theoretical contradictions . The essential nature of the atomic nucleus was established with the discovery of the neutron by James Chadwick in 1932 and the determination that it was a new elementary particle , distinct from the proton . Both the proton and neutron were presumed to be elementary particles until the 1960s when they were determined to be composite particles built from quarks .
What was the nationality was the person who established the essential nature of the atomic nucleus?
What was the nationality was the person who established the essential nature of the atomic nucleus ?
English
English