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Final state interactions in two-particle interferometry

D. Anchishkin·U. Heinz·P. Renk
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Abstract

We reconsider the influence of two-particle final state interactions (FSI) on two-particle Bose-Einstein interferometry. We concentrate in particular on the problem of particle emission at different times. Assuming chaoticity of the source, we derive a new general expression for the symmetrized two-particle cross section. We discuss the approximations needed to derive from the general result the Koonin-Pratt formula. Introducing a less stringent version of the so-called smoothness approximation we also derive a more accurate formula. It can be implemented into classical event generators and allows to calculate FSI corrected two-particle correlation functions via modified Bose-Einstein "weights".

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D. Anchishkin, U. Heinz, P. Renk. 1997-10-22. Final state interactions in two-particle interferometry. https://doi.org/10.1103/physrevc.57.1428

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