Minutes of Level 3 Trigger Meeting, 18 December 1997

Attendees: Cathy Cretsinger, Gregory Dubois-Felsmann, Al Eisner, Ed Frank, Larry Gladney, Fred Kral, Songhoon Yang

[Agenda]

Action items from last meeting

2. Code testing:
   Cathy built an executable in Framework with all of the L3 filters included. Four output lines are defined, one for each script and one for the OR of all scripts. Cathy reports that the executable runs but gets only 47.6% efficiency for the L3Dch filter ==> contact Anders. A status report from Cathy is included in this directory. Cathy will talk to Ed to find out how to get background files to test the executable's rejection. She will also work on developing a L1 Global fiducial cut filter (since finished, see her announcement).
3. Background Mixing Studies
   Ed gave a preliminary report on background studies. He and Vivek Suraiya have produced 5 runs of 1200 events each (C2 or D2 or Y1) for vacuumX10. They have 14,000 frames made with x10 nominal backgrounds. All of the bmgas (low-energy beam) files are done. The next step is to run with safe triggers to see rejection vs. open trigger. There are enough background frames for 1500 physics events with x10 nominal backgrounds. It is not clear yet what fraction of vacuum events will pass the safe trigger.
   
4. Trigger Production re-run:
   Refer to earlier discussions for background on this issue. This meeting continues that discussion.
   Fred reports that there is a large discrepancy between Monte Carlo and commissioning data for lost particle backgrounds. This is being studied in detail and will take some time to sort out. We can conclude from this that it is not worthwhile to consider producing new TURTLE rays in time for the rerun, but will have to check again after the holidays to determine a time scale for production of new rays for L3 studies.

   Discussions among the Trigger, Level3, and Simulation/Production groups have produced a tentative plan for dividing up the labor for the new production run. The tentative plan is:

   Activity Locus of responsibility defineRuns formulation Trigger group ffread, .db inputs Trigger group production site coordination, job allocation, etc. Production managers manpower to run jobs, collect output, make tapes do book keeping. Production team plus Recon ghit monitor Recon/Sim Collation of final data to make background frames. Trigger group.

   Al asks about the need to generate Bhabhas along with uds and charm run for physics signatures. Larry will check into the existence of a "new" Bhabha generator for producing e⁺e^-gamma-gamma events.

Milestones Discussion:

Cathy leads a discussion on defining physics goals to be achieved by meeting the benchmarks. We agree that the physics goals are the desired endpoints but keep to the present milestones list to define the operational activities for the group. A modified set of milestones which incorporates comments from this meeting and via e-mail will be sent around before the time of the next meeting on Jan. 8.

What follows is an edited "short" list of comments for modifications made during the meeting .

1. Supporting an outside consumer by mid-January is not do-able. Our aim should be to support an OEP consumer that needs all the L3 events by the end of January.
2. The above implies that output lines and filter modules should be defined so that output lines can be used by the OEP consumer. It also implies that L3 code should be in a standard release.
3. 1 tool plus L3Master should be up and running under OEP by the end of January.
4. Add an explicit milestone that addresses our commitment to meeting our physics goals.

Other Business

Please send corrections or amplifications to Larry.

The next phone meeting will be on 08 January at 10:30 AM PST.