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arXiv · hep-ph/0303118

Gamma^* - Gamma^* Scattering: Saturation and Unitarization in the BFKL approach

S. Bondarenko·M. Kozlov·E. Levin
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Abstract

In this paper $γ^* - γ^*$ scattering with large, but more or less equal virtualities of two photons is discussed using BFKL dynamics, emphasizing the large impact parameter behavior ($b_t$) of the dipole-dipole amplitude. It is shown that the non-perturbative contribution is essential to fulfill the unitarity constraints in the region of $b_t > 1/2 m_π$, where $m_π$ is pion mass. The saturation and the unitarization of the dipole-dipole amplitude is considered in the framework of the Glauber-Mueller approach. The main result is that we can satisfy the unitarity constraints introducing the non-perturbative corrections only in initial conditions (Born amplitude).

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S. Bondarenko, M. Kozlov, E. Levin. 2003-03-14. Gamma^* - Gamma^* Scattering: Saturation and Unitarization in the BFKL approach. https://arxiv.org/abs/hep-ph/0303118

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