High energy electromagnetic processes in amorphous and inhomogeneous media

Electromagnetic Wave Packets in the Theory of Bremsstrahlung and Transition Radiation by High-Energy Electrons

“…The value 2γ 2 λ presenting in the condition (35) is known in the theory of radiation by ultrarelativistic particles as the formation length or the coherence length [1,2].…”

“…In the theory of radiation by relativistic electrons the length l C has a name of the coherence length of the radiation process [1,2]. Within this length the interference effects in radiation are significant.…”

“…For large distances from the scattering point, namely in the wave zone of the radiation process (z ≫ 2γ 2 / ω) the integral in (58) can be calculated with the use of stationary phase method [36]. It leads to the well known expression for radiation distribution from the bremsstrahlung theory [1,4,37]:…”

“…A lot of high-energy physical processes develop within large domains of space along the direction of particle motion (see, for example monographs [1][2][3] and references in them). In the case of electromagnetic processes the size of these domains can substantially exceed sometimes not only interatomic distances of substance but the size of experimental facility (detectors) as well [1,2,[4][5][6][7][8][9][10][11][12][13]. Essential in this case is the fact that interaction of particles with atoms and experimental facility situated within such domains and outside them can substantially differ.…”

“…For ultra relativistic particles, however, this does not happen at once. The length within which this process develops has a name of the coherence length of the radiation process [1,2]. It is 2γ 2 times larger than the length λ of the considered radiated waves (γis here the electron's Lorentzfactor).…”