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arXiv · 0804.4282

Failure of the collinear expansion in calculation of the induced gluon emission

P. Aurenche·B. G. Zakharov·H. Zaraket
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Abstract

We demonstrate that the collinear expansion fails in the case of gluon emission from a fast quark produced in $eA$ DIS. In this approximation the N=1 rescattering contribution to the gluon spectrum vanishes. We show that the higher-twist approach by Guo, Wang and Zhang [4,5] based on the collinear expansion is wrong. The nonzero gluon spectrum obtained in [4,5] is a consequence of unjustified neglecting some important terms in the collinear expansion.

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P. Aurenche, B. G. Zakharov, H. Zaraket. 2008-04-27. Failure of the collinear expansion in calculation of the induced gluon emission. https://doi.org/10.1134/s0021364008110039

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