Minutes
* Next meeting: 19 July 1998 (Location yet to be determined)
* Elton Smith reported that the hall will be accessible for run preparation from Tuesday, 2 June, 8 am, to at least through the afternoon of Friday, 5 June. Bernhard Mecking later presented the firm schedule showing access until swing shift Saturday, 6 June. Beam could be in the hall by Sunday, 8 June. Any volunteers for shifts?
* An open discussion of RadPhi politics was held. By lack of dissension, the current leadership arrangement was countenanced. Commitment to the experiment appears solid. A motion was made that the collaboration consider the formalization of procedures for electing leaders, admitting new members, choosing speakers, and submitting publications. While agreeing that the motion was reasonable, others voiced the opinion that the present, semi-formal approach should suffice as long as the group remains reasonably small (and reasonably amenable-a necessary condition even when formal procedures are adopted). This topic will be revisited.
* Craig Steffen showed the results of his calibration exercises on 480K (out of 3 million taken) events. He looked at two cluster events, after making fiducial and minimum energy cuts, and found 3500 pi^0 events (width 18 MeV) and around 400 eta events (width 20 MeV). About 400 blocks were instrumented. See plot at
http://anthrax.physics.indiana.edu/ crsteffe/radphi.html
* Richard Jones reviewed the results of his studies regarding backgrounds. See ``Technical Notes'' in RadPhi internal pages
http://www.cebaf.gov/ radphi/OEO/Welcome.html
or
http://zeus.phys.uconn.edu/radphi/brems-5-98/index.html
The good news is that the helium bag and lead shielding appear to have reduced the background in the CPV by a factor of 15. The UPV seems to provide an addition factor of 2 reduction. Richard had previously showed that a factor of 20 reduction was necessary for the experiment to be viable.
* Scott Teige reported that the MAM performed as expected. There is much play yet to reduce rates without cutting into efficiency. Settings can go from 0 to 255. In April, a setting of 50 was shown to result in very high purity of ``real'' events. The standard setting during that run was 15. There's a long plateau between those two settings as indelibly etched in red on the conference room white board.
* Craig Steffen reviewed the hardware tasks necessary for the run. In no particular order, these include:
- Surveying the helium bag and alignment components
- Recabling tagger electronics for the rpd-less trigger
- In stalling (5) beam monitor cables to the forward carriage
- Commission z-motion system
- Enable and align carriages
- Install bases and tubes
- Configure beam position monitor logic
- Remove target counter
- Fabricate a HV trip alarm
* Phillip Folck informed us of his work certifying 360 pmts.
* David Armstrong recited his litany of outstanding software tasks, which includes moving cvs to urs3, getting the dispatcher going, automating LGD monitoring and diagnostics, assembling only histograms, getting the event display tuned, creating tape and calibration databases, and get a working calibrator. Only the last seems to be completed, although others are being worked. Laura McGlinchey, UR undergrad, will oversee the RadPhi web pages and will look into (g)dbm for the tape database.
* Scott Teige presided over the formulation of a list of rules of interaction with g6 during the June run. This will be a part of the Conduct of Operations document Scott has composed. The list will be passed by Claude Marchand for comment/approval and then forwarded to MCC. Mike Spata, from MCC, joined in the discussion.
* Richard Jones led off the discussion of running conditions and the impact on g6's concern over flux normalization. Claude Marchand and Bernhard Mecking were present, and the solution(s) proposed as a result of Richard's work were seen as adequate. Mike Spata all but assured everyone that the beam will behave and we'll have no need to worry about much, other than diligence.
* Finally, preparations for 6 GeV running, which may occur as
early as next July, were discussed. In addition to the need to
understand the detector (determine acceptances, measure
reasonably well known processes, see some fully contained phi
decays, and maybe nail omega -> eta gamma), three significant
projects must be undertaken soon: moving the IU detector from
BNL to TJNAF (P. Rubin and E. Scott), constructing a rpd-less
trigger (S. Teige and P. Smith), and installing a soft photon
``veto'' [R. Jones (jetset) and, maybe, S. Teige and E. Scott
(heavy liquid)]. B. Mecking encouraged a request to the planners
for 6 GeV beam the second half of next summer, to run, again,
with g6, which will control the beam for the first 30 days
while we'll control it the second 30 days.