J. J. Thomson

J. J. Thomson
Thomson in 1915
30th Master of Trinity College, Cambridge
In office
1918–1940
Preceded byHenry Montagu Butler
Succeeded byGeorge Macaulay Trevelyan
42nd President of the Royal Society
In office
1915–1920
Preceded byWilliam Crookes
Succeeded byCharles Scott Sherrington
Born
Joseph John Thomson

(1856-12-18)18 December 1856
Died30 August 1940(1940-08-30) (aged 83)
Cambridge, England
Alma materOwens College
Trinity College, Cambridge (BA)
Known for
Children
Awards
Scientific career
FieldsPhysics
InstitutionsUniversity of Cambridge
Academic advisorsLord Rayleigh
Edward John Routh
Notable students
3rd Cavendish Professor of Physics
In office
1884–1919
Preceded byLord Rayleigh
Succeeded byErnest Rutherford
Signature

Sir Joseph John Thomson OM FRS[1] (18 December 1856 – 30 August 1940) was an English physicist and Nobel Laureate in Physics who is credited with the discovery of the electron, the first subatomic particle to be found.

In 1897, Thomson showed that cathode rays were composed of previously unknown negatively charged particles (now called electrons), which he calculated must have bodies much smaller than atoms and a very large charge-to-mass ratio.[2] Thomson is also credited with finding the first evidence for isotopes of a stable (non-radioactive) element in 1913, as part of his exploration into the composition of canal rays (positive ions). His experiments to determine the nature of positively charged particles, with Francis William Aston, were the first use of mass spectrometry and led to the development of the mass spectrograph.[2][3]

Thomson was awarded the 1906 Nobel Prize in Physics for his work on the conduction of electricity in gases.[4] Thomson was also a teacher, and seven of his students went on to win Nobel Prizes: Ernest Rutherford (Chemistry 1908), Lawrence Bragg (Physics 1915), Charles Barkla (Physics 1917), Francis Aston (Chemistry 1922), Charles Thomson Rees Wilson (Physics 1927), Owen Richardson (Physics 1928) and Edward Victor Appleton (Physics 1947).[5] Only Arnold Sommerfeld's record of mentorship offers a comparable list of high-achieving students.

  1. ^ Rayleigh (1941). "Joseph John Thomson. 1856–1940". Obituary Notices of Fellows of the Royal Society. 3 (10): 586–609. doi:10.1098/rsbm.1941.0024.
  2. ^ a b Cite error: The named reference Profile was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Jones was invoked but never defined (see the help page).
  4. ^ "J.J. Thomson – Biographical". The Nobel Prize in Physics 1906. The Nobel Foundation. Retrieved 11 February 2015.
  5. ^ Sengupta, Sudipto (6 April 2015). "Extraordinary Professor: JJ Thomson and his Nobel Prize Factory". Probashi. Durga Puja & Cultural Association (India). Retrieved 7 August 2022. His Nobel Laureate students include Rutherford, Aston, Wilson, Bragg, Barkla, Richardson, and Appleton