Abstract
The problem of saturation of parton densities in deep inelastic scattering (DIS) in the limit x → 0 and in heavy-ion collisions at very high energies is investigated in the framework of Reggeon theory. It is emphasized that the shadowing effects are important in a definite kinematical region. The model which includes unitarity effects and gives a good description of structure functions and diffractive processes in DIS is discussed. In the limit x → 0, the “saturation” of parton densities is achieved. The Gribov approach to interaction with nuclei allows one to describe structure functions of nuclei in the small-x region. It is shown how the prediction of the Glauber model for the density of hadrons produced in the central rapidity region in nucleus-nucleus interactions is modified due to shadowing of small-x partons. Calculations show that shadowing effects are important at RHIC energies, but the situation is far from saturation. Production of particles with large transverse momenta and jets is discussed.
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From Yadernaya Fizika, Vol. 68, No. 5, 2005, pp. 812–816.
Original English Text Copyright © 2005 by Kaidalov.
This article was submitted by the author in English.
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Kaidalov, A.B. The problem of “saturation” in DIS and heavy-ion collisions. Phys. Atom. Nuclei 68, 779–783 (2005). https://doi.org/10.1134/1.1935011
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DOI: https://doi.org/10.1134/1.1935011