Thomas Royds

Thomas Royds (born April 11, 1884 in Moorside near Oldham in Lancashire , England, † May 1, 1955 in England) was an English physicist. He is known for having proven in 1909, together with Ernest Rutherford and Hans Geiger , that alpha particles are doubly positively charged helium nuclei. Besides, Royds was a solar researcher.

life and work

Thomas Royds studied physics at the University of Manchester and stayed there to do spectroscopic research. From 1907 to 1909 he worked with Rutherford. They published four times together, the most important being the identification of the alpha particles. In 1902 Ernest Rutherford and his student Frederick Soddy formulated a decay theory to explain radioactivity. Rutherford and Royds confirmed this theory in 1909 when they were able to prove that alpha particles are doubly positively charged helium ions.

From 1909 to 1911 Royds worked with Friedrich Paschen in Tübingen and Heinrich Rubens in Berlin on infrared rays. In 1911 he got his doctorate in Manchester. In 1911 he went to India as deputy director of the Kodaikanal Solar Physics Observatory in Madras, where he researched the shift of the spectral lines in the solar spectrum . Between 1913 and 1937 he published 49 publications there and others in journals, for example in Nature . When director Evershed retired in 1922, Royds succeeded him. In 1929 he led an expedition to Thailand together with Professor Stratton from Cambridge in order to observe a solar eclipse there, which was hardly possible because of the clouds. In 1936 he represented the head of all observation stations in India for a year, which also included the Meteorological Service of India. He then traveled with Stratton for a successful solar observation in Hokkaidō , Japan.

In 1937 Royds returned to England and retired two years later. Another year later the post of astronomer and head of the Istanbul University observatory became vacant. At the urging of the British, Royds applied and got the job. Because of the war around the Cape of Good Hope , the trip there led to Cairo in 1942 and from there to Istanbul. In the autumn of 1947, after his contract had expired, he finally returned to England, where he died in 1955. He had two daughters and a son.

Works

• with E. Rutherford: The Nature of the Alpha Particle from Radioactive Substances. In: Philosophical Magazine. ser 6, Volume 17, 1909, pp. 281–286 ( digitized version )

Sources and web links

• Obituary - Times of London. May 4, 1955, page 15d.
• Obituary - Indian Journal of Meteorology and Geophysics. Quarterly Volume 6, July 1955, No. 3, page 280
• Indian Institute of Astrophysics Repository - Search for Royds!
• Ernest Marsden, quoted on page 328 of the Rutherford Scientist Supreme by John Campbell, AAS Publications 1999