arXiv subjects

Jan Wissmann

Publications and source records attributed to Jan Wissmann.

2 recordsLinked to original sources

arXiv2026

PineAPPLv1: fast and flexible theory predictions for present and future colliders

We present PineAPPLv1, a library designed to provide accurate and flexible interpolation tables of partonic cross sections that can be convolved with parton distribution functions (PDFs) and fragmentation functions (FFs) for the fast evaluation of high-energy physical observables. The core feature of the new release is the support of multiple convolutions involving initial- and final-state hadronic particles, with any polarisation, that are associated with PDFs and FFs. The library simultaneously supports polarised and unpolarised distributions that obey space-like or time-like evolution, and is developed for an arbitrary number of them, even if physical processes typically only require a few. Control of scale choices when more than one scale characterises a scattering process is also possible. We describe the technical details of the new representation of interpolation coefficients stored in the grid, and we demonstrate the capabilities of the library in a few phenomenological cases of interest. Specifically, we compute predictions for single-inclusive pion production in unpolarised and polarised proton-proton collisions and in semi-inclusive deep-inelastic scattering. We show how, in each case, PDF, FF, and scale uncertainties compare to each other and highlight the potential of PineAPPL as an essential ingredient for precision physics at current and future colliders.

hep-ph↗

arXiv2024

PineAPPL Grids of Open Heavy-Flavor Production in the GM-VFNS

Many next-to-leading order QCD predictions are available through Monte Carlo (MC) simulations. Usually, multiple CPU hours are needed to calculate predictions at a required precision, which is unfeasible for global PDF analyses. This problem is solved by a process known as gridding: The values of the hard-scattering cross-section are calculated only once with the MC program, and then interpolated and stored in look-up tables (grids) of the kinematical variables. To obtain the physical predictions, they are convolved with the PDFs (e.g. during the fitting stage in a PDF global analysis), which takes a tiny fraction of the time needed to calculate the MC results. This is possible with PineAPPL, a library tackling the aforementioned process of grid creation and convolution. In this work, we use PineAPPL to grid the predictions for open heavy-flavor production in the general-mass variable-flavor-number scheme (GM-VFNS). In the GM-VFNS, the differential cross-section interpolates between the fixed-flavor-number scheme (FFNS) and the zero-mass variable-flavor-number scheme (ZM-VFNS). These are each only valid in different kinematical regions, in which the GM-VFNS cross-section reproduces the FFNS and ZM-VFNS as the limiting cases of high energies and small masses, respectively. Better than permille agreement is achieved between the grids and the MC predictions, while at the same time not substantially increasing the time of the MC calculations.

hep-ph↗