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Coherent bremsstrahlung research originated with the 1955 papers by Dyson and Uberall, Ter-Mikaelian, and Ferretti.
Its intermediate status thirty years later has been documented by Saenz and Uberall in the book Coherent Radiation
Sources (A. W. Saenz and H. Uberall, editors), Springer, Berlin 1985. The first precision experiments were carried out
by Diambrini-Palazzi et al. (1960) in Frascati shortly after the theory had been developed; see also Timm (1969). After
experimentation by dozens of electron accelerator laboratories all over the world, there are presently measurements being
made by Arends et al. at the University of Mainz (MAMI, 855 MeV), Klein et al. at the University of Bonn (ELSA, 3
GeV), at CERN (20-170 GeV) by Avakian of the Yerevan Physics Institute and others, and with electron energies of 6
GeV at the Jefferson Laboratory, Newport News, VA (F. J. Klein, Catholic University, spokesperson). At Jefferson Lab,
linearly polarized quasi-monochromatic coherent-bremsstrahlung photons [peaked at 1.8GeV, with polarization (after
collimation) of 84%] are being used for the production (off protons) of ρ and ω mesons among others.
Recent theoretical research deals with coherent bremsstrahlung in quasicrystals (Fusina, Langworthy, and Saenz,
2001), and with planar and axial coherent bremsstrahlung in a diamond crystal (Chouffani, Endo, and Uberall 2001-2),
both at low energies. In the latter study, in which the concept of axial coherent bremsstrahlung is now stressed (while in
the related processes of planar and axial channeling radiation this distinction is well known), photon emission occurs
here not necessarily in the forward direction.
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