Cosmic rays

Topics discussed include: Bruno Rossi, Gilberto Bernardini, Ettore Majorana, radioactivity, Antonio Lo Surdo, Antonio Garbasso, Lise Meitner, Ernest Rutherford, C. T. R. Wilson, John Cockcroft, P. M. S. Blackett, Gleb Wataghin, Gian Carlo Wick, Franco Rasetti, Enrico Persico, Dirac's theory, nuclear physics, Emilio Segre, cosmic rays, James Chadwick, Cambridge University, Shimizu, George Gamow, Frederic Joliot, Cavendish laboratory, P. L. Kapitsa, Hans Geiger, Maurice Goldhaber, Victor Weisskopf, David Frisch, Ehrenburg, Carl Anderson, Guglielmo Marconi, Louis de Broglie, P. A. M. Dirac, fellowship from National Council of Research, Arthur Holly Compton, Surgio de Benedetti, Giulio Racah, Sergei Vavilov, University at Sao Paolo, William Bragg, Cecil Powell, sigma star, and pi-meson decay.

Topics discussed include: Bruno Rossi, Gilberto Bernardini, Ettore Majorana, radioactivity, Antonio Lo Surdo, Antonio Garbasso, Lise Meitner, Ernest Rutherford, C. T. R. Wilson, John Cockcroft, P. M. S. Blackett, Gleb Wataghin, Gian Carlo Wick, Franco Rasetti, Enrico Persico, Dirac's theory, nuclear physics, Emilio Segre, cosmic rays, James Chadwick, Cambridge University, Shimizu, George Gamow, Frederic Joliot, Cavendish laboratory, P. L. Kapitsa, Hans Geiger, Maurice Goldhaber, Victor Weisskopf, David Frisch, Ehrenburg, Carl Anderson, Guglielmo Marconi, Louis de Broglie, P. A. M. Dirac, fellowship from National Council of Research, Arthur Holly Compton, Surgio de Benedetti, Giulio Racah, Sergei Vavilov, University at Sao Paolo, William Bragg, Cecil Powell, sigma star, and pi-meson decay.

This is one of a number of interviews that Katherine Sopka conducted with Harvard physics faculty regarding the history of the Harvard Department of Physics. Street joined the Harvard physics faculty in 1932.  The primary themes are the department and his cosmic ray research in the 1930s.  Street describes his decision to leave the Bartol Research Foundation in Swarthmore, PA; the salary that Harvard offered; other faculty members, especially Theodore Lyman; conditions in the Physics Department; and the courses that were offered.  In the second half of the interview, he focuses on a detailed description of his cosmic ray research and of the colleagues and graduate students who worked with him. 

Early education; studies biophysics at Universität Frankfurt and Kaiser-Wilhelm Institut (Friedrich Dessauer, Rievsky); physics training (Erwin Madelung, Meissner); Dessauer's political troubles. Fellowship to Institut Radium (Marie Curie), 1933; building geiger counters (Frédéric Joliot-Curie); life and staff at Institut (Irene Joliot-Curie, Jean Perrin, Hans von Halban, Peter Preiswerk, Lew Kowarski, Rosenblum); Institut's role in development of nuclear physics (P.M.S. Blackett, Giuseppe Occhialini); first nuclear physics conference in Zurich (Paul Scherrer), 1933; London Conference of 1934 (Max Born, Maurice Goldhaber); F. Joliot-Curie thinking about accelerators and about building a cyclotron (Pierre Weiss); Gentner continues gamma ray work (Lise Meitner). Gentner leaves Institut after Curie's death; fellowship at Institute for Medical Research, Kaiser-Wilhelm Institut, Heidelberg (Walther Bothe), 1935-1938; also lectures at Frankfurt on radioactivity, gamma rays, x-rays, and cosmic rays; builds the first Van der Graaf machine in Germany, 1936; first to use gamma rays to look for nuclear photo effect (Fowler, Lauritsen). Travels to United States to study cyclotrons (James Fisk), 1938; spends several months at University of California, Berkeley (E. O. Lawrence, Donald Cooksey); the fission story (Niels Bohr, J. R. Oppenheimer); calibrating ionization chamber and experimental work in fission; life and pre-war politics at Berkeley and Stanford University (Felix Bloch); visits California Institute of Technology (Fowler, Lauritsen, Max Delbrück); travels to Washington, DC (George Gamow, Edward Teller, Fleming, Merle Tuve); and ends tour in New York City (John R. Dunning, Lawrence, Bohr). Returns to Europe; visits John Cockcroft at University of Cambridge. Returns with wife to Germany in April, 1938; plans for Siemens to build cyclotron in Heidelberg canceled. Sent to Paris to interview F. Joliot-Curie on whereabouts of heavy water, July 1940; private meeting afterwards; works in Paris with F. Joliot-Curie on cyclotron, 1940-1942; returns to Heidelberg to build own cyclotron, 1942-1944. Difficulties of re-establishing nuclear physics in Germany after World War II (Cockcroft, Konrad Adenauer); building up new laboratories; CERN, DESY.

In this interview Leon Fisher and Robert Varney discuss topics such as: Leonard Loeb; Willliam Allis; Sandy Brown; New York University; Wayne Nottingham; Julius Molnar; Phillip Morse; people from the Massachusetts Institute of Technology (MIT) and Bell Laboratories; Brookhaven National Laboratory; Norris Bradbury; Dan Alpert; Gerhard Weissler; Lockheed Corporation; John A. Hornbeck; Ben Bederson; Homer Hagstrum; microwaves; radar development; T. D. Lee; Alfred Von Engel; Army Research Office; Office of Naval Research; Air Force Office of Scientific Research; ionized gases; Ted Holstein; cosmic rays; neutrons; Lester Germer; Ronald Geballe; gas discharges; American Physical Society; Karl Darrow; William Shockley.

Recollections of Solvay and Volta Conferences, associations with Franck, Bohr and Mme. Curie; development of AHC’s cosmic ray interest, world cosmic ray expeditions 1931-34, anecdotes and memories of places visited; Compton-Millikan controversy; comments on Century of Progress Exposition 1933; memories of stay at Oxford on AHC’s Eastman Professorship 1934-35, associates at Oxford; recollection of European colleagues Aston, Fermi, Heisenberg and Sommerfeld. About AHC: Chairman of Physics Dept. at Chicago 1940-45, earlier contacts with Chicago, relation to Michelson, widening of philosophical interests, long-term consultant to General Electric Co. (1926-45), consultant to National Cancer Advisory Council and Chicago Tumor Institute. Disappointment in Compton family life, close working relationship between AHC and Betty, relation of physicists’ wives to their husbands’ work; Betty’s assessment of her career.

This telephone interview deals with Bowyer’s research in non-solar x-ray astronomy while he worked at the Naval Research Laboratory in Washington, D.C. He discusses his functions as a member of a group of scientists, directed by Herbert Friedman, who performed numerous observations of cosmic x-ray sources in 1963 and after. Bowyer relates the competitive, spirit that existed between the NRL group and the Massachusetts Institute of Technology-American Science and Engineering, Inc. group that made the first conclusive observation of x-rays originating from outside the solar system.

This telephone interview deals with Bowyer’s research in non-solar x-ray astronomy while he worked at the Naval Research Laboratory in Washington, D.C. He discusses his functions as a member of a group of scientists, directed by Herbert Friedman, who performed numerous observations of cosmic x-ray sources in 1963 and after. Bowyer relates the competitive, spirit that existed between the NRL group and the Massachusetts Institute of Technology-American Science and Engineering, Inc. group that made the first conclusive observation of x-rays originating from outside the solar system.

After describing his upbringing and undergraduate education in physics at Renesselaer, Bleach (b. June 7, 1944) reviews his subsequent enrollment in the PhD program in physics at the University of Maryland. He then discusses his work at Goddard while in the PhD program, including initially developing solid state detectors for cosmic ray experiments; moving to an X-ray astronomy group headed by Dr. Elihu Boldt; developing and testing proportional counters in balloons, rockets, and satellites; use of mechanical and modulation collimators in the counters; and interaction with other research groups. Bleach next describes his thesis on Cygnus X-1 and work at NRL after completing his PhD program, including initially building and conducting experiments with detectors for the gamma ray group under HERO, and subsequent move to the laboratory diagnostics area in which he still is involved.

Concentrates on Bergstrahl's work at NRL (1946-56), principally as an experiment integrator for rocket flights, with additional coverage of his later work at Ford Aeroneutronics and Aerospace Corporation. Besides discussing the procedures and problems of integrating experiments, Bergstrahl relates his work at NRL on early attempts at high altitude photography, on rocket impact point prediction systems, and on cosmic ray balloon research. The discussion of his years (1956-62) at Ford Aeroneutronics examines his work on lunar and planetary studies, including work on the Ranger Hard Lander.