Physics meeting on generators, BPACK, ... Aug 22, 2000 (Entire LHCb
collaboration)
From: olivier.schneider@iphe.unil.ch
Date: 8/2/00
Time: 9:21:22 AM
Remote Name: 137.138.142.33
Remote User:
Comments
Dear colleagues,
Important decisions are being taken and are still to be taken by LHCb
(and more generally the LHC experiments) as to which generators to use
in the Gaudi framework, how to decay the particles, how to handle
particle properties, ... So it probably time for LHCb to review the
situation with respect to the available physics generator packages as
well as the BPACK project (see text attached at the end of this message
for more info on BPACK).
I therefore would like to organize a special physics task force meeting
dedicated to these very important aspects. The goal of this meeting is
to inform a wider fraction of the collaboration of these issues
currently
discussed in specialized groups, to generate more interest for these
important questions, hopefully get more people involved in the field,
and finally allow the work already done to be presented. We should also
make some progress in understanding whether we would like to develop our
own B decay package or participate in a larger project with ATLAS and
others.
The meeting will take place at CERN in the afternoon of Tuesday August
22, 2000. The agenda will include:
- Handling of particle properties in Gaudi (Gloria Corti)
- Status of the available physics generators (Paolo Bartalini)
- Status of the BPACK project (Paolo Bartalini)
- Simulation of specific decays: example of the radiative decays of B0
mesons (TBA, Clermont-Ferrand)
There is room for additional contributions, which you are welcome to
propose.
It would also be nice if we could collect already before the meeting
some of the physics and analysis requirements, that you, physicist
planning to do physics with LHCb, may have. Please send your ideas,
comments, questions, requests to Paolo Bartalini, who has agreed to
collect your response.
Cheers,
Olivier
======================================
BPACK:
BPACK is an acronym to indicate the software package needed by the LHC
experiments in order to simulate the decays of heavy-flavor hadrons.
LHCb is currently using Pythia 6.1 as QCD model and QQ 9.2 as decay
model. In the future the migration to object oriented technologies will
allow for a high level modularization of the physics generators,
offering the possibility to rely on the best known product for each step
of the physics
simulation (hard interaction, perturbative evolution, fragmentation,
decays). Obviously LHCb is particularly interested in getting the best
decay model, and presumably also in contributing to its development in
the
forthcoming years.
During the second half of 1999, a few BPACK meetings have been held,and
the first physics and software requirements have been collected:
http://msmizans.home.cern.ch/msmizans/production/Bpack/Bpack.html
The BPACK proposal was rediscussed at the LHCb physics generator
mini-workshop held in Clermont-Ferrand:
http://p.home.cern.ch/p/pbartali/www/clermont/
It was concluded that LHCb might need a dedicated package and, as a
consequence, LHCb temporarily suspended its participation in the BPACK
project. An LHCb note was produced (LHCb 99-051): "Towards a unified
Monte Carlo for B meson decay simulations", Z.J. Ajaltouni et al.
In the mean time BPACK activities continued to evolve. The project
became a BaBar/CDF/ATLAS collaboration that concentrates on the
improvement of EvtGen, the decay package currently used by BaBar. You
may want to give a look at the minutes of the BaBar/CDF/ATLAS EvtGen
meeting recently
held in Berkeley:
http://msmizans.home.cern.ch/msmizans/production/Bpack/minutes5.html
At some point (perhaps quite soon) LHCb should decide either to
participate in the BPACK activities or start our own project on a
dedicated decay package.
|
