Compton scattering: Test of the double differential cross section in the relativistic impulse approximation

doi:10.1016/0375-9601(83)90773-9

Physics Letters A

Volume 95, Issue 1, 11 April 1983, Pages 29-31

https://doi.org/10.1016/0375-9601(83)90773-9 Get rights and content

Abstract

Cross sections $d^{2} σ/ d Ω d E_{γ2}$ for bound Compton scattering are calculated in the relativistic impulse approximation using DHFS wave functions. Agreement is observed with experiment for E_γ1 = 279 and 662 keV at the peak of the profiles. Discrepancies found at the high-energy side are only partly explained by second-order S-matrix calculations.

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The doubly differential cross section for Compton scattering from K-shell atomic electrons is calculated in the relativistic impulse approximation (lA) and compared with an exact relativistic second order S-matrix calculation based on the independent particle approximation (IPA). Comparison is made for several atoms and for incident photon energies up to 320 keV. A new criterion for the validity of the impulse approximation is given in terms of the average electron momentum contributing to the scattered photon spectrum rather than the momentum expectation value of the orbital electron. In the energy range considered here the impulse approximation gives a good description of the portion of the spectrum in which the new criterion is fulfilled.
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Compton scattering: Test of the double differential cross section in the relativistic impulse approximation☆

Abstract

Comput. Phys. Comm.

Univ. Pittsburgh Rep. No. PITT

Aust. J. Phys.

J. Phys.

Phys. Rev.

Z. Phys.

Z. Phys.

Phys. Rev.