HELAC-Onia 2.0: an upgraded matrix-element and event generator for heavy quarkonium physics
arXiv:1507.03435
Abstract
We present an upgraded version (denoted as version 2.0) of the program HELAC-Onia for the automated computation of heavy-quarkonium helicity amplitudes within non-relativistic QCD framework. The new code has been designed to include many new and useful features for practical phenomenological simulations. It is designed for job submissions under cluster enviroment for parallel computations via Python scripts. We have interfaced HELAC-Onia to the parton shower Monte Carlo programs Pythia 8 and QEDPS to take into account the parton-shower effects. Moreover, the decay module guarantees that the program can perform the spin-entangled (cascade-)decay of heavy quarkonium after its generation. We have also implemented a reweighting method to automatically estimate the uncertainties from renormalization and/or factorization scales as well as parton-distribution functions to weighted or unweighted events. A futher update is the possiblity to generate one-dimensional or two-dimensional plots encoded in the analysis files on the fly. Some dedicated examples are given at the end of the writeup.
55 pages, 21 figures
References in corpus (14)
- The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
- Heavy quarkonium: progress, puzzles, and opportunities
- Comparative study of various algorithms for the merging of parton showers and matrix elements in hadronic collisions
- A standard format for Les Houches Event Files
- J/psi (psi') production at the Tevatron and LHC at O(α_s^4v^4) in nonrelativistic QCD
- Reconciling J/psi production at HERA, RHIC, Tevatron, and LHC with NRQCD factorization at next-to-leading order
- QCD corrections to J/psi and Upsilon production at hadron colliders
- Polarization for Prompt J/psi, psi(2s) production at the Tevatron and LHC
- Helac-Phegas: a generator for all parton level processes
- QCD corrections to J/psi polarization of hadronproduction at Tevatron and LHC
- production at the LHC challenges nonrelativistic-QCD factorization
- Impact of hadroproduction data on charmonium production and polarization within NRQCD framework
- Quarkonium production in the LHC era: a polarized perspective
- MINT: a Computer Program for Adaptive Monte Carlo Integration and Generation of Unweighted Distributions