Jean Danysz (11 March 1884 – 4 November 1914) born Jan Kazimierz Danysz, was a French physicist of

Polish Polish may refer to: * Anything from or related to Poland, a country in Europe * Polish language * Poles Poles,, ; singular masculine: ''Polak'', singular feminine: ''Polka'' or Polish people, are a West Slavic nation and ethnic group, w ...

extraction. He was an assistant of

Maria Skłodowska-Curie Marie Salomea Skłodowska–Curie ( , , ; born Maria Salomea Skłodowska, ; 7 November 1867 – 4 July 1934) was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity. She was the first ...

and notable in the development of

beta Beta (, ; uppercase , lowercase , or cursive ; grc, βῆτα, bē̂ta or ell, βήτα, víta) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Modern Greek, it represents the voiced labiod ...

spectrometry. Danysz made considerable advances on the

magnetic deflection In physics, deflection is a change in a moving object's velocity, hence its trajectory, as a consequence of contact (collision) with a surface or the influence of a non-contact force field. Examples of the former include a ball bouncing off the ...

techniques of Baeyer, Hahn and Meitner, placing the source (he used radium) in a capillary tube under a slit, with a photographic plate in the same horizontal plane. By this means the known number of lines (later understood to be conversion lines) superimposed on the beta energy spectrum of RaB + RaC went from 9 to 27 (later work by

Robinson Robinson may refer to: People and names * Robinson (name) Fictional characters * Robinson Crusoe, the main character, and title of a novel by Daniel Defoe, published in 1719 Geography * Robinson projection, a map projection used since the 1960 ...

and Rutherford found 64; 16 from RaB and 48 from RaC). He finished his doctoral thesis in 1913, and by 1914 he was considered by Rutherford as a leading researcher into

beta decay In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta particle (fast energetic electron or positron) is emitted from an atomic nucleus, transforming the original nuclide to an isobar of that nuclide. For ...

, but he did no further work. He enlisted in the French army in 1914 and was killed in action near

Cormicy Cormicy () is a commune in the Marne department in north-eastern France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Am ...

Publications

J. Danysz, Le Radium 9, 1 (1912); 10, 4 (1913) Danysz, J. ''Recherches expérimentales sur les β rayons de la famille du radium'' Ann. Chim. Phys. 30 (1913) 241–320

Family

* He was the son of biologist Jean Danysz (1860-1928).''Bulletin littéraire et scientifique'' (Association des anciens élèves de l'Ecole polonaise) - 1914/12/15 (Année 39, N°316) * He was the father of physicist

Marian Danysz Marian Danysz (March 17, 1909 – February 9, 1983) was a Polish physicist, Professor of Physics at Warsaw University. Son of Jan Kazimierz Danysz. In 1952, he co-discovered with Jerzy Pniewski a new kind of matter, an atomic nucleus, which ...

(1909–1983).

References

1884 births 1914 deaths 20th-century French physicists French Army soldiers French military personnel killed in World War I {{Physicist-stub