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Interpolation and evolution of parton distribution functions with ChiliPDF

Jul 15, 2019, 4:55 PM
2220 A Chair : Paolo Gunnellini

2220 A Chair : Paolo Gunnellini

PDFs/alpha_S/Soft PDFs/Soft/Alpha_S I


Riccardo Nagar (DESY)


We present an efficient implementation of the solution of the DGLAP equations for single and double parton distributions (PDFs and DPDs). The implemented algorithm is based on the Chebyshev interpolation of these functions. For PDF evolution, our method allows for a higher numerical accuracy using a considerably smaller amount of grid points compared to existing methods. As a consequence of the high interpolation accuracy, operations on PDFs such as differentiation and Mellin convolution can be done in a fast way and with a high level of precision. Furthermore, the DPD evolution is realized to a satisfactory degree of accuracy using an affordable number of points, and allows for two independent renormalization scales for the two partons. For both PDFs and DPDs, DGLAP evolution and flavor matching are implemented up to NNLO.

Primary authors

Frank Tackmann (DESY) Markus Diehl (DESY) Riccardo Nagar (DESY)

Presentation materials