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arXiv · hep-ph/9412341

Numerical Solution of Altarelli-Parisi Equations

R. Kobayashi·M. Konuma·S. Kumano·M. Miyama
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Abstract

We discuss numerical solution of Altarelli-Parisi equations in a Laguerre-polynomial method and in a brute-force method. In the Laguerre method, we get good accuracy by taking about twenty Laguerre polynomials in the flavor-nonsinglet case. Excellent evolution results are obtained in the singlet case by taking only ten Laguerre polynomials. The accuracy becomes slightly worse in the small and large $x$ regions, especially in the nonsinglet case. These problems could be implemented by using the brute-force method; however, running CPU time could be significantly longer than the one in the Laguerre method.

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R. Kobayashi, M. Konuma, S. Kumano, M. Miyama. 1994-12-21. Numerical Solution of Altarelli-Parisi Equations. https://doi.org/10.1143/ptps.120.257

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