NLO WG NLOWorking Group
established in January, 2000
A collaboration of people from the Atlas-Japan
group and the Minami-Tateya
group , for developing NLO (Next-to-Leading Order)
Monte Carlo event generators for high energy hadron-collision
experiments , for example, those at FNAL Tevatron and
CERN LHC
.
Goal
To establish an automatic NLO event-generator
generation system for hadron collisions, based on the GRACE system
and implementing NLL parton showers for both
initial and final states. Activities
GR@PPA
(GRace At Proton-Proton/Anti-proton
collisions): a GRACE -based event generator
framework for hadron collisions. The program can be embedded in a
general purpose event generators PYTHIA
and HERWIG
. Some event generators, still at the tree level (leading order), have
been developed in this framework.
Automatic NLO event-generator
generation: in principle, using the GRACE system, we can
automatically calculate NLO matrix elements by adding new
vertices, propagators and external legs for corrections arising from
higher-order loop diagrams. A suitable extention is also
necessary in the diagram generation part of the GRACE system. In
addition, in the application to hadron collisions where Q-dependent
parton distribution functions (PDFs) are adopted, we have to solve the double-counting
problem of additional parton emission.
NLL (Next-to-Leading Log) initial-state parton
shower : presently available initial-state parton shower
simulations are all based upon the LL (Leading Log) approximation. We
want to
go beyond it!
ME–PS matching in the simulation of multi-jet production in hadron collisions using a subtraction method, S. Odaka, N. Watanabe, and Y. Kurihara, PTEP 2015 (2015) 053B04; arXiv:1409.3334 [hep-ph]
Matching between matrix elements and parton
showers using a Leading-Log subtraction method in NLO-QCD, Y.
Kurihara, in Proc.
of CPP Symposium 2001, Tokyo, Nov. 27 - 30, 2001; hep-ph/0207214
Integration of GRACE and PYTHIA, K. Sato
et al. , Proc. VII International Workshop on
Advanced Computing and Analysis Techniques in Physics Research
(ACAT2000), eds. P.C. Bhat
and M. Kasemann, AIP Conference Proceedings 583, 214 (2001) (American Institute
of Physics, Milville, New York, 2001), p. 214; hep-ph/0104237;
KEK Preprint 2000-134
Presentations
Introduction
of GR@PPA event generator, S. Tsuno, XVIIIth
International Workshop
on High Energy Physics and Quantum Field Theory (QFTHEP 2004), St.
Petersburg,
17 - 23 Jun., 2004
NLO
event generator for LHC, Y. Kurihara, Mini-Workshop
on Physics Simulation
for LHC, KEK, 5 - 6 Apr., 2004
Integration of GRACE and PYTHIA , S. Odaka, VII
International Workshop on Advanced Computing and Analysis Techniques in
Physics
Research (ACAT2000), FNAL, 16 - 20 Oct., 2000