In the past few months we have accumulated a great deal of
high-quality physics data; in addition, during the entire past year
there has been a great deal of activity in developing and using the
offline analysis software. It appears that the state of the offline
software is such that a major data analysis run using the JLAB batch
farms may be practical very soon, at least as a prototype effort.
A major missing piece, however, of the overall scheme to produce cross
sections is the acceptance calculation from the Monte Carlo
simultation, 'GSIM'. A number of people have been working on
improving this code, but because of lack of manpower the progress
has lagged behind the reconstruction software. This is particularly
difficult in that even if the GSIM code were ready to run, it will
require months (at least) of running to produce high-statistics
simulated data.
To address this issue, a new group has been formed from newly
available manpower within the collaboration. The name of the group
is the 'GSIM Focus Group', because we will be focusing on a very
specific class of problems with the simulation.
The GSIM Focus group will meet weekly, with a specific agenda
distributed beforehand and minutes distributed afterward. The class
of problems which we will focus on will be highly prioritized toward
the goal of producing publication-quality acceptance calculations as
soon as possible. Each project will have a list of responsible
parties and a target deadline. Each person in the 'core' group is
asked to commit at least 33% of his/her working time to this
project, in order to be efficient. Additional 'contributing' members
are also welcome, although we are requesting a time estimate from
everyone involved. If you or members of your group are interested in
participating, please let me know.
The group meetings will include telephone conference calls and will
include use of the Web-4M software, which allows 'free' web-based
whiteboard and slide show capability. This will allow offsite workers
to contribute signficantly to the project.
There is already a large group of people working on GSIM. This
effort, led by Maurik Holtrop and Dennis Weygand, is making
important contributions toward the long-term goal of having the
optimal simulation for a variety of purposes. The GSIM Focus Group
will draw on the expertise of the larger group and coordinate with
their efforts and plans; the distinction is that our group will
focus exclusively on the near-term goal of publication-quality
acceptance
calculations. Many people from the larger body will be involved in
all of our meetings. For information on the existing effort, consult
Maurik Holtrop's very useful web page, presently at:
http://einstein.sr.unh.edu/Maurik/gsim_info.shtml
The minutes of our meetings will be distributed to the clas_gsim
mailing list, the class_offline mailing list, and perhaps to the
calcom mailing list. If you would like to receive the minutes and
you are not on any of these, let me know. We are interested in
receiving feedback from the collaboration on our decisions and
progress.
The very first focus of the group will be to calculate acceptances
for final states including an electron and one charged hadron. The
two highest-priority items required for this are:
1) Get time-based tracking to work on GSIM data.
2) Speed up the code by a factor of 10-100.
Core group members: Time estimate
Will Brooks (JLAB) 33%
Kyungseon Joo (UVA) 33%
Laurent Farhi (Saclay) 40%
David Rowntree (MIT) 33%
Jianguo Zhao (MIT) 33%
Contributing group members: Time estimate
Volker Burkert (JLAB) 10%
2 students (MIT) 2 x 10 hours/week
several others have expressed interest
As is evident from the above, the MIT group has made a significant
manpower commitment to this project, as well as promising a large
amount of CPU time on their DEC/Alpha compute farm.
Let me know if you are interested in joining this group, or if you
have other comments or questions. It is clear that producing reliable
acceptance calculations is absolutely critical to the CLAS research
program, so the success of this work is in the interests of every
collaboration
member.
Best regards,
- Will Brooks
757-269-6391