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A Path Integral Approach to Inclusive Processes

O. Nachtmann·A. Rauscher
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Abstract

The single-particle inclusive differential cross-section for a reaction $a+b\to c+X$ is written as the imaginary part of a correlation function in a for ward scattering amplitude for $a+b\to a+b$ in a modified effective theory. In this modified theory the interaction Hamiltonian $\tilde H_I$ equals $H_I$ in the original theory up to a certain time. Then there is a sign change and $\tilde H_I$ becomes nonlocal. This is worked out in detail for scalar field models and for QED plus the abelian gluon model. A suitable path integral for direct calculations of inclusive cross sections is presented.

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O. Nachtmann, A. Rauscher. 2000-05-15. A Path Integral Approach to Inclusive Processes. https://doi.org/10.1007/s100520000439

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