ggxy: A flexible library to compute gluon-induced cross sections

We present the library ggxy, written in C++, which can be used to compute partonic and hadronic cross sections for gluon-induced processes with at least one closed heavy quark loop. It is based on analytic ingredients which avoids, to a large extent, expensive numerical integration. This results in significantly shorter run-times than other similar tools. Modifying input parameters, changing the renormalization scheme and varying renormalization and factorization scales is straightforward. In Version 1 of ggxy we implement all routines which are needed to compute partonic and hadronic cross sections for Higgs boson pair production up to next-to-leading order in QCD. We provide flexible interfaces and allow the user to interact with the built-in amplitudes at various levels. PROGRAM SUMMARY Program title: ggxy Developer’s repository link: https://gitlab.com/ggxy/ggxy-release Licensing provisions: GNU General Public License Version 3 Programming language: C++ and Fortran External routines/libraries used: avhlib, boost, Collier, CuTtools, eigen, LHAPDF, lievaluate, OneLOop, Recola, CRunDec Nature of problem: The computation of partonic and hadronic cross sections for gluon-induced processes. ... mehrIn Version 1, the Higgs boson pair production process is implemented at next-to-leading order in Quantum Chromodynamics. Solution method: For the virtual corrections, deep expansions around the forward and high energy limit are used. Restrictions: The run-times depend crucially on the requested precision. Results at the per-mille level can be obtained in about 30 minutes using a single core on a AMD Ryzen Threadripper PRO 3955WX processor. References and Links: are provided in the paper