Electron-positron pair creation is analyzed for an arrangement involving three external fields: a high-frequency gamma photon, the Coulomb field of a nucleus, and a strong laser wave. The frequency of the incoming gamma photon is assumed to be larger than the threshold for pair production in the absence of a laser, and the peak electric field of the laser is assumed to be much weaker than Schwinger's critical field. The total number of pairs produced is found to be essentially unchanged by the laser field, while the differential cross section is drastically modified. We show that the laser can channel the angular distribution of electron-positron pairs into a narrow angular region, which also facilitates experimental observation.
E. Lotstedt et al., "Laser Channeling of Bethe-Heitler Pairs," Physical Review Letters, vol. 101, no. 20, pp. 203001-1-203001-4, American Physical Society (APS), Nov 2008.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevLett.101.203001
Keywords and Phrases
Angular Distribution; Electric Fields; Electrons; Photons; Positrons; Angular Regions; Coulomb Fields; Critical Fields; Differential Cross Sections; Experimental Observations; External Fields; Gamma Photons; High Frequencies; Laser Fields; Laser Waves; Pair Creations; Pair Productions; Peak Electric Fields
International Standard Serial Number (ISSN)
Article - Journal
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