HELAC-Onia: An automatic matrix element generator for heavy quarkonium physics

Published: 01-11-2013| Version 1 | DOI: 10.17632/3mrbvgmgxn.1
Hua-Sheng Shao


Abstract By the virtues of the Dyson-Schwinger equations, we upgrade the published code HELAC to be capable to calculate the heavy quarkonium helicity amplitudes in the framework of NRQCD factorization, which we dub HELAC-Onia. We rewrote the original HELAC to make the new program be able to calculate helicity amplitudes of multi P-wave quarkonium states production at hadron colliders and electron-positron colliders by including new P-wave off-shell currents. Therefore, besides the high efficiencies i... Title of program: HELAC-Onia. Catalogue Id: AEPR_v1_0 Nature of problem An important way to explore the law of the nature is to investigate the heavy quarkonium physics at B factories and hadron colliders. However, its production mechanism is still unclear, though NRQCD can explain its decay mechanism in a sufficiently satisfactory manner. The substantial K-factor in heavy quarkonium production processes also implies that the associated production of quarkonium and a relatively large number of particles may play a crucial role in unveiling its production mechanism. Versions of this program held in the CPC repository in Mendeley Data AEPR_v1_0; HELAC-Onia.; 10.1016/j.cpc.2013.05.023 AEPR_v2_0; HELAC-Onia 2.0; 10.1016/j.cpc.2015.09.011 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)