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A Semianalytical Method to Solve Altarelli-Parisi Evolution Equations

Pietro Santorelli·Egidio Scrimieri
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Abstract

We discuss a new method to solve in a semianalytical way the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations at NLO order in the x-space. The method allows to construct an evolution operator expressed in form of a rapidly convergent series of matrices, depending only on the splitting functions. This operator, acting on a generic initial distribution, provides a very accurate solution in a short computer time (only a few hundredth of second). As an example, we apply the method, useful to solve a wide class of systems of integrodifferential equations, to the polarized parton distributions

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Pietro Santorelli, Egidio Scrimieri. 1999-09-08. A Semianalytical Method to Solve Altarelli-Parisi Evolution Equations. https://arxiv.org/abs/hep-ph/9909289

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