Program title: HELAC-Onia 2.0
Catalogue identifier: AEPR_v2_0
Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEPR_v2_0.html
Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland
Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html
No. of lines in distributed program, including test data, etc.: 1513282
No. of bytes in distributed program, including test data, etc.: 17036140
Distribution format: tar.gz
Programming language: Python, Fortran 77, Fortran 90, C++.
Operating system: Unix-like platform.
Classification: 4.4, 11.1, 11.2, 11.5.
Catalogue identifier of previous version: AEPR_v1_0
Journal reference of previous version: Comput. Phys. Comm. 184(2013)2562
External routines: LHAPDF
Does the new version supersede the previous version?: Yes
Nature of problem: Heavy quarkonium production processes provide an important way to investigate QCD in its poorly known non-perturbative regime. Its production mechanism has attracted extensive interests from the high-energy physics community in decades. The qualitative and quantitative description of heavy-quarkonium production requires complex perturbative computations for high-multiplicity processes in the framework of the well established non-relativistic effective theory, NRQCD, and reliable Monte Carlo simulations to reproduce the collider environment.
Solution method: Based on a recursion relation, the program is able to calculate the helicity amplitudes of the high-multiplicity heavy- quarkonium-production processes. Several modules are also designed for dedicated simulations:
The code has been interfaced with the parton shower Monte Carlo programs;
A decay module to let heavy quarkonia decay with correct spin-correlations has been implemented;
The code estimates the theoretical uncertainties and analyzes the generated events on the fly;
The code is compliant with multi-threading/multi-core usage or cluster processors.
Reasons for new version: Improved and expanded functionalities.
Summary of revisions: Many new features were added and several important bugs were fixed. The new features extend the range of the physical applications. With the new interface, it also helps to improve the user-friendliness of the program.
Running time: It depends on the process to be calculated and the required accuracy.