Marietta Blau | |
|---|---|
 | |
| Born | (1894-04-29)29 April 1894 Vienna,Austria-Hungary |
| Died | 27 January 1970(1970-01-27) (aged 75) Vienna, Austria |
| Nationality | Austrian |
| Occupation | Physicist |
| Known for | Usingnuclear emulsions to detecthigh energy particles |
Marietta Blau (29 April 1894 – 27 January 1970) was an Austrian physicist credited with developing photographicnuclear emulsions that were usefully able to image and accurately measure high-energy nuclear particles and events, significantly advancing the field ofparticle physics in her time. For this, she was awarded theLieben Prize by theAustrian Academy of Sciences. As a Jew, she was forced to flee Austria whenNazi Germany annexed it in 1938, eventually making her way to the United States. She was nominated for Nobel Prizes in both physics and chemistry for her work, but did not win. After her return to Austria, she won theErwin Schrödinger Prize from the Austrian Academy of Sciences.
Blau was born on 29 April 1894 in a middle-classJewish family, to Mayer (Markus) Blau, a court lawyer and music publisher, and his wife, Florentine Goldzweig. After having obtained the general certificate of education from the girls' high school run by the Association for the Extended Education of Women,[1][2] she studied physics and mathematics at theUniversity of Vienna from 1914 to 1918; her PhD, on the absorption of gamma rays, was awarded in March 1919.[3][1] Blau is credited with developing (photographic)nuclear emulsions that were usefully able to image and accurately measurehigh energy nuclear particles and events. Additionally, this established a method to accurately study reactions caused bycosmic ray events. Her nuclear emulsions significantly advanced the field ofparticle physics in her time. For her work, she was nominated several times, during the period 1950 to 1957, for theNobel Prize in Physics and once for theNobel Prize in Chemistry byErwin Schrödinger andHans Thirring.[4][5]
From 1919 to 1923, Blau held several positions in industrial and University research institutions in Austria and Germany; in 1921, she moved toBerlin to work at a manufacturer of x-ray tubes, a position she left in order to become an assistant at the Institute for Medical Physics at theUniversity of Frankfurt am Main.[1] From 1923 on, she worked as an unpaid scientist at theInstitute for Radium Research of theAustrian Academy of Sciences in Vienna. A stipend by the Austrian Association of University Women made it possible for her to do research also inGöttingen and Paris (1932/1933) at theCurie Institute.[6]
In her Vienna years, Blau's main interest was the development of thephotographic method of particle detection. The methodical goals which she pursued were the identification of particles, in particular alpha-particles and protons, and the determination of their energy based on the characteristics of the tracks they left in emulsions; there, she developed a photographic emulsion technique used in the study of cosmic rays,[1] being the first scientist to use nuclear emulsions to detect neutrons. For this work, Blau and her former studentHertha Wambacher received theLieben Prize of the Austrian Academy of Sciences in 1937. It was her greatest success when, also in 1937, she and Wambacher discovered "disintegration stars" in photographic plates that had been exposed tocosmic radiation at an altitude of 2,300 metres (≈7,500 feet) above sea level. These stars are the patterns of particle tracks from nuclear reactions (spallation events) ofcosmic-ray particles with nuclei of the photographic emulsion.
Because of her Jewish descent, Blau had toleave Austria in 1938 after the country's annexation by Nazi Germany, a fact which caused a severe break in her scientific career. She first went to Oslo. Then, through the intercession ofAlbert Einstein,[1][7] she obtained a teaching position at theInstituto Politécnico Nacional inMexico City and later atUniversidad Michoacana de San Nicolás de Hidalgo.[7] Conditions in Mexico made research extremely difficult for her, and she seized an opportunity to move to the United States in 1944.[4]
In the United States, Blau worked in industry until 1948, afterwards (until 1960) atColumbia University,Brookhaven National Laboratory and theUniversity of Miami. At these institutions, she was responsible for the application of the photographic method of particle detection in high-energy experiments at particle accelerators.
In 1960, Blau returned to Austria and conducted scientific work at the Institute for Radium Research until 1964 – again without pay. She headed a working group analyzing particle-track photographs from experiments atCERN and supervised a dissertation in this field.[8][9] In 1962, she received theErwin Schrödinger Prize of theAustrian Academy of Sciences,[10] but an attempt to make her also a corresponding member of the Academy was not successful.[11]
Marietta Blau died in Vienna from cancer on 27 January 1970.[12] Her illness was related to her unprotected handling of radioactive substances[1] as well as her cigarette smoking over many years. No obituary appeared in any scientific publication.[11]
In 1950,Cecil Powell received theNobel Prize in Physics for the development of the photographic method for particle detection and the discovery of thepion by use of Blau's method.[citation needed]
