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17-525: In 1947, G. C. Baldwin and G. S. Klaiber observed the giant dipole resonance (GDR) in photonuclear reactions , and in 1972 the giant quadrupole resonance (GQR) was discovered, and in 1977 the giant monopole resonance (GMR) was discovered in medium and heavy nuclei. Giant dipole resonances may result in a number of de-excitation events, such as nuclear fission , emission of neutrons or gamma rays, or combinations of these. Giant dipole resonances can be caused by any mechanism that imparts enough energy to

34-521: A college degree in physics. Baldwin was an avid amateur astronomer, grinding his own lenses and building his own telescopes; fisherman; self-taught pianist, entertaining friends by playing by ear; and historical researcher. One of Baldwin's notable accomplishments was locating an inscription left by the Dominguez-Escalante expedition of 1776, discovered originally in 1884 by his father on a surveying expedition in northern Arizona. Baldwin organized

51-436: A number of de-excitation events, such as nuclear fission , emission of neutrons or gamma rays, or combinations of these. Giant dipole resonances can be caused by any mechanism that imparts enough energy to the nucleus. Classical causes are irradiation with gamma rays at energies from 7 to 40 MeV, which couple to nuclei and either cause or increase the dipole moment of the nucleus by adding energy that separates charges in

68-470: A prominent peak at about 20 MeV in the cross section for photons (1947), (1948), which was not anticipated by the nuclear physics community. This " giant dipole resonance " discovered by Baldwin and Klaiber was subsequently explained theoretically by Edward Teller and Maurice Goldhaber , and others. Baldwin's research with low-energy electron scattering on noble gases extended the scattering cross-section data to very low energies, well under 1 eV (1967),

85-515: A technically difficult task. His book "An Introduction to Nonlinear Optics" (1969) helped bridge the gap in knowledge between specialists in the field and engineers and technical managers involved with this new technology. Baldwin, along with GE colleagues, developed ideas for nuclear radiation analogues of the optical laser, now known as the gamma-ray laser, or Gamma-Ray Amplification by Stimulated Emission of Radiation (GRASER) . He launched international efforts to define and quantify issues facing

102-758: The Argonaut Research Reactor facility at Argonne National Laboratory , conducting neutron measurements and developing operational procedures (1958-1959). He was a Professor of Nuclear Engineering at Rensselaer Polytechnic Institute in Troy, New York (1967-1977). He continued his research at the Los Alamos National Laboratory in Los Alamos, New Mexico (1977-1987). Baldwin's fields of research included photo-nuclear reactions with bremsstrahlung radiation from electron accelerators , resulting in

119-626: The University of Illinois at Urbana–Champaign in 1943. His Ph.D. thesis was on the nuclear photo-effect ; his thesis advisor was Donald William Kerst . Continuing at Illinois, he taught college-level physics in the Army Specialized Training Program during World War II. He joined General Electric Research Laboratory in Schenectady, New York, as a physicist working on industrial research and development (1944-1967). He directed

136-558: The 1995/1996 Museum of New Mexico expeditions that found the Escalante inscription and documented this in the Journal of the Southwest (1999). Giant resonance In nuclear physics , giant resonance is a high-frequency collective excitation of atomic nuclei , as a property of many-body quantum systems . In the macroscopic interpretation of such an excitation in terms of an oscillation,

153-510: The average gamma decay. High energy electrons of >50 MeV may cause the same phenomenon, by coupling to the nucleus via a "virtual gamma photon", in a nuclear reaction that is the inverse (i.e., reverse) of internal conversion decay. This nuclear physics or atomic physics –related article is a stub . You can help Misplaced Pages by expanding it . George C. Baldwin George Curriden Baldwin (May 5, 1917 – January 23, 2010)

170-457: The development of this advanced idea, working with many academic colleagues, including R. V. Khokhlov and V. I. Gol'danskii of the USSR and J. C. Solem of Los Alamos, opening an entirely new field of physics and making bold, creative attempts to bring the concept to fruition (1963), (1965), (1975). He authored an early bibliography of literature on the problem of developing gamma-ray lasers, covering

187-472: The discovery of the giant dipole resonance ; orbit dynamics of synchrotrons ; nuclear reactor physics; electrical propulsion for space; low-energy electron scattering in gases; nonlinear optics ; and investigation of the feasibility of a gamma-ray laser . His early research involved perfecting GE's 100 MeV Betatron for use as an x-ray source. Using bremsstrahlung radiation from the betatron beam, he and G. S. Klaiber excited uranium nuclei and observed

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204-603: The kinetics of gamma-ray lasers. Decades of his gamma-ray laser work, together with that of others, is assessed in a paper (1981) and a second assessment concentrates on later work on recoilless gamma-ray lasers (1997). These review papers contain an extensive list of references. He collaborated with J. C. Solem on research on the use of x-ray microholography to image biological specimens (1982). Baldwin's 57-year marriage to his wife Winifred, who collaborated as copy editor and typist for many of his publications, produced three children and seven grandchildren, of these three obtained

221-438: The most prominent giant resonance is a collective oscillation of all protons against all neutrons in a nucleus. In 1947, G. C. Baldwin and G. S. Klaiber observed the giant dipole resonance (GDR) in photonuclear reactions , and in 1972 the giant quadrupole resonance (GQR) was discovered, and in 1977 the giant monopole resonance (GMR) was discovered in medium and heavy nuclei. Giant dipole resonances may result in

238-431: The nucleus. Classical causes are irradiation with gamma rays at energies from 7 to 40 MeV, which couple to nuclei and either cause or increase the dipole moment of the nucleus by adding energy that separates charges in the nucleus. The process is the inverse of gamma decay , but the energies involved are typically much larger, and the dipole moments induced are larger than occur in the excited nuclear states that cause

255-509: The nucleus. The process is the inverse of gamma decay , but the energies involved are typically much larger, and the dipole moments induced are larger than occur in the excited nuclear states that cause the average gamma decay. High energy electrons of >50 MeV may cause the same phenomenon, by coupling to the nucleus via a "virtual gamma photon", in a nuclear reaction that is the inverse (i.e., reverse) of internal conversion decay. This nuclear physics or atomic physics –related article

272-491: The period 1917 through 1979 (1979). Baldwin investigated methods for detecting nuclear stimulated emission, seeking to demonstrate coherent emission from nuclear states, but establishing that a number of innovative ideas were unworkable. He and his colleagues identified criteria necessary for the process of laser action at gamma-ray energies. He collaborated on theoretical issues, on experiments to demonstrate isomer separation by selective photoionization (1983), and on modeling of

289-539: Was an American theoretical and experimental physicist. He was a professor of nuclear engineering at Rensselaer Polytechnic Institute and a scientist working at the General Electric Research Laboratory and at the Los Alamos National Laboratory . He wrote a book on Nonlinear Optics and authored or co-authored over 130 technical papers. George C. Baldwin earned his B.S. degree in physics from Kalamazoo College in 1939 and his Ph.D. in physics from

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