Beam-shape effects in nonlinear Compton and Thomson scattering

Journal Article · Mon Feb 15 00:00:00 EST 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.022125· OSTI ID:21408195

Heinzl, T ^[1]; Seipt, D; Kaempfer, B ^[2]

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1. School of Computing and Mathematics, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)
2. Forschungszentrum Dresden Rossendorf, Post Office Box 51 01 19, D-01314 Dresden (Germany)

We discuss intensity effects in collisions between beams of optical photons from a high-power laser and relativistic electrons. Our main focus is on the modifications of the emission spectra due to realistic finite-beam geometries. By carefully analyzing the classical limit we precisely quantify the distinction between strong-field QED Compton scattering and classical Thomson scattering. A purely classical, but fully covariant, calculation of the bremsstrahlung emitted by an electron in a plane-wave laser field yields radiation into harmonics, as expected. This result is generalized to pulses of finite duration and explains the appearance of line broadening and harmonic substructure as an interference phenomenon. The ensuing numerical treatment confirms that strong focusing of the laser leads to a broad continuum while higher harmonics become visible only at moderate focusing, and hence lower intensity. We present a scaling law for the backscattered photon spectral density which facilitates averaging over electron beam phase space. Finally, we propose a set of realistic parameters such that the observation of intensity-induced spectral red shift, higher harmonics, and their substructure becomes feasible.

• OSTI ID: 21408195
• Journal Information: Physical Review. A, Vol. 81, Issue 2; Other Information: DOI: 10.1103/PhysRevA.81.022125; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BREMSSTRAHLUNG
COMPTON EFFECT
ELECTRON BEAMS
EMISSION SPECTRA
FOCUSING
GEOMETRY
HARMONICS
LASER RADIATION
LASERS
LINE BROADENING
NONLINEAR PROBLEMS
PHASE SPACE
QUANTUM ELECTRODYNAMICS
RED SHIFT
RELATIVISTIC RANGE
SCALING LAWS
SPECTRAL DENSITY
THOMSON SCATTERING
BASIC INTERACTIONS
BEAMS
ELASTIC SCATTERING
ELECTRODYNAMICS
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC RADIATION
ENERGY RANGE
FIELD THEORIES
FUNCTIONS
INELASTIC SCATTERING
INTERACTIONS
LEPTON BEAMS
MATHEMATICAL SPACE
MATHEMATICS
OSCILLATIONS
PARTICLE BEAMS
QUANTUM FIELD THEORY
RADIATIONS
SCATTERING
SPACE
SPECTRA
SPECTRAL FUNCTIONS