Few-photon electron-positron pair creation in the collision of a relativistic nucleus and an intense x-ray laser beam

Journal Article · Sun Aug 01 04:00:00 UTC 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.70.023412· OSTI ID:20645924

Mueller, C; Gruen, N ^[1]; Voitkiv, A B ^[2]

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1. Institute for Theoretical Physics, University of Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen (Germany)
2. Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

We study the nonlinear process of e{sup -}e{sup +} pair creation by a nucleus which moves at a relativistic energy in the laboratory frame and collides with an intense x-ray laser beam. The collision system under consideration is chosen in such a way that the simultaneous absorption of at least two photons from the laser wave is required in order to exceed the energy threshold of the reaction. We calculate total and differential rates for both free-free and bound-free pair production. In the case of free-free pair creation we demonstrate the effect of the laser polarization on the spectra of the produced particles, and we show that at very high intensities the total rate exhibits features analogous to those well known from above-threshold ionization rates for atoms. In the case of bound-free pair creation a singularity is found in the laboratory frame angular distribution of the produced positron. This singularity represents a distinct characteristic of the bound-free pair production and allows one to separate this process from free-free pair creation even without detecting a bound state of the captured electron. For both types of pair creation we consider the dependences of the total rates on the collision parameters, give the corresponding scaling laws, and discuss the possibility to observe these nonlinear processes in a future experiment.

• OSTI ID: 20645924
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 2 Vol. 70; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ABSORPTION
ANGULAR DISTRIBUTION
ATOMS
BOUND STATE
ELECTRON PAIRS
ELECTRONS
IONIZATION
MULTI-PHOTON PROCESSES
NONLINEAR PROBLEMS
OPTICS
PAIR PRODUCTION
PHOTON-ATOM COLLISIONS
PHOTONS
POLARIZATION
POSITRONS
QUANTUM MECHANICS
RELATIVISTIC RANGE
SCALING LAWS
SINGULARITY
X-RAY LASERS