CDF Detector Simulation|
Last modified: Fri Aug 26 13:33:43 CDT 2005
Standalone MC Production: MC@NLO
MC@NLO is a standalone matrix element generator which matches
Next-to-Leading-Order calculations of rates for QCD
processes with a parton shower Monte Carlo event generator
Currently, the recommended method
for generating MC events which can be imported into the CDF
Run II simulation framework is to run MC@NLO with standalone
HERWIG, write the output in
format, then use the
LesHouches package to read the StdHep files into
cdfSim for re-decay and detector simulation. The
megenConfig package should be used to process
multi-file StdHep samples with the luminosity weighted,
run-dependent MC scheme, mcProduction. This path
allows the option of using
JIMMY for simulating
the underlying event instead of the HERWIG internal code,
since JIMMY should run seamlessly with standalone HERWIG
(this might not be the case for CDF HERWIG).
MC@NLO 3.1 manual (gzipped Postscript).
- CDF Note 7769: Documentation for the UserInfo and
UserInfoColl classes -- useful for storing
A description of the MC@NLO formalism.
A description of the application to heavy quark pair production.
Event Weights: MC@NLO produces "unweighted"
events in the sense that the magnitude of the event weights
may be configured to be 1.0. The sign of these
weights is however important and should be kept through
detector simulation and reconstruction, then used when
observables are histogrammed. There are two ways of storing
the event weight: encode the sign of the weight in the energy
of the colliding proton, recorded in the HEPG bank (see the first
example below), or store the weight in the event record. A
UserInfo object may be used to employ the latter method, as is
done in cdfSim by MCInfoModule (see CDF 7769).
An example of how to install and run MC@NLO with StdHep output
courtesy of David Waters
(update coming soon).
- An updated example (for v3.1), based upon David Waters' code (see
the previous example), can be found here.
This example also includes modifications which allow one to set the
HERWIG random generator seeds in the top-level MC@NLO script.
- How (and why) to process multi-file StdHep format samples with
mcProduction using the