Minutes of LBNL E895 Meeting - Tuesday, Oct. 21, 1997

In attendance: Dieter Best (DB), Dan Cebra (DC), Heng Liu (HL),
        Sergei Panitkin (SP), Nathan Stone (NS), Gulshan Rai (GR)

News Items:

- CVS (NS):
        - 3 new btf source files (mostly reorganization)
          (editor's note: major upgrade soon to come)
        - modification to sys/tas_tio_ds.f to fix XDF bug
        - new PID module from Heng

- Slow Simulator (GR):
        - much progress.  "We appear to be very close" --GR
          (editor's note:  full functionality was achieved on Oct. 22!)

- Computing request (NS):
        - There was a request by Auckland to do work on the LBNL cluster
          until TAS3 works on OSF.  This request was approved, and details
          will be sent out to parties concerned.

- Collaboration Committee Decision regarding trackers (GR):
        - a committee vote was cast to choose which tracker to use for
          official DST production.  That vote came up 4-4, a tie.  The
          immediate implication is that both trackers are viable for DST
          production, and that this choice will remain the prerogative of the
          individual institutions.
        - This should not contribute to numerical disagreements between
          institutions regarding specific physics observables, due to the
          well-defined boundaries of study specified by each institution at
          the earlier collaboration meeting.

Progress Reports:

- Pentium Farm (SP):
        - NFS is running on all machines, although specific mount/export
          instructions are not installed.  SP intends for us to make use
          of the implicit resource sharing of Solaris before going over to NFS.
        - Solaris-specific "auto-mounting" is enabled and functional
        - Mike's OSU PII scripts are here now, and SP has set up a similar
          directory structure to make use of them.
        - no WWW service from within the PII farm (or KSTAR4).
        - Compilers:
          f77/f90 for a single CD: $1300
          f77/f90, debugger, profiler, analyzer, etc: $3500

- DST Production (HL):
        - 6 GeV jobs crashed on PDSF due to full disk...
        - HL will copy 8 GeV data to disk to make available for "full-running"
          of PII farm (tape 75).  This should commence tonight.

- BTF/JTF comparisons (DB):
        - DB simulated 1000 K0s (672 events with charged tracks) and ran
          them through both trackers and his V0 finder.

          IFIT=3 means helix fit with MPS field map for JTF
          IFIT=1 means simple helix fit without MPS field map (constant field)

        tracker                 <Minv>          sigma           # found
        -------                 -------         -------         -------
        JTF (IFIT=3)            499 MeV         3.5 MeV         871
        BFT (helix+MPSfield)    499 MeV         3.5 MeV         877

        JTF (IFIT=3)            500 MeV         2.6 MeV  narrow fit about peak
        BFT (helix+MPSfield)    500 MeV         2.7 MeV  narrow fit about peak

        JTF (IFIT=1)            498 MeV         5.0 MeV         875
        BTF (simple helix fit)  498 MeV         4.5 MeV         844

        - next step: try implementing the fieldmap fit
          editor's note:  these additions were completed on Oct. 22, and
          provided a significant improvement in V0 reconstruction. The
          results are incorporated in the above table

        Final note. EOSGX simulations always produce events with MPS field
        regardless of any constant field switch setting. This has caused a
        lot of confusion in the debugging process.

        A new version with substantial additions will be available in the
        CVS library shortly.

- Flow Studies (HL):
        (editor's note: a long presentation ensued.  following are just a
         few hilights)
        - Implements Qphi reaction plane flattening
        - discussion of Flow value correction factor using arguments
          from S. Voloshin
          - described that the correction will increase our current flow values
            (more for higher beam energies than for lower)
          - suggested performing "Fourrier analysis", since "everyone
            at QM97 will speak in terms of both"...