Eur. Phys. J. C (2003) 30: 497-501
https://doi.org/10.1140/epjc/s2003-01318-x

theoretical physics

Factorization theorems for high energy nn, $\gamma p$ and $\gamma\gamma$ scattering

Department of Physics and Astronomy, Northwestern University, IL 60208, Evanston, USA

Abstract

The robustness of the factorization theorem for total cross sections, $\sigma_{nn}/\sigma_{\gamma p}=\sigma_{\gamma p}/\sigma_{\gamma\gamma}$ for nn (the even portion of pp and ${\bar p}p$ scattering), $\gamma p$ and $\gamma\gamma$ scattering, originally proved by Block and Kaidalov using an eikonal formalism, is demonstrated. Factorization theorems for the nuclear slope parameter B and $\rho$, the ratio of the real to the imaginary portion of the forward scattering amplitude, are derived under very general conditions, using analyticity and the optical theorem.