Radphi Video Conference 6/28/02

June 28, 2002
University of Connecticut
Storrs, CT

Present: Craig S., Dan K., D. Armstrong, R. Jones, M. Kornicer, Dan S.

• presented contents of his new technical note

• http://www.physics.wm.edu/~steiner/radphi/cluster.htm
• decided not to use Elgd cut but rather to compare Elgd and Etagger. There is a peak around -1 GeV. He cut on DelataE > 550 MeV. It is not very different from a cut on Elgd at 4.5 GeV. He is now trying to include hits in the BGV into the analysis to catch some of the additional energy. Suggestion is use the BGV a veto, after the recoil proton has been masked off. The next step will be to look at LGD vs tagger energy and try to determine the correlation.

• G0 run starts Aug. 24 for 10 days. In order for David to be able to devote time to the Radphi collaboration meeting, it will probably have to come after that run is completed.

• Dan has run a number of pi0pi0 simulations and profiled the cuts he plans to make on the real data. One part of question ws the loss due "recoil good" after the 3-layer BSD trigger was satisfied. He will look into that.
• after all cuts were made, he had almost 0.7% acceptance. This is low - we expected something more like 2-3%. One reason might be that he requires E > 5.0 GeV in the forward (LGD) photons. This cut will be useful to eliminate background in the real data, but it is brutal.
• Another issue that came up was how many events were being eliminated by an artificial pre-selection. Dan is doing that requires the event to have all 4 gamma in the acceptance of the LGD. He said that without this cut his final sample increases by 25%. These events seem to be bad reconstructions. Some concern was expressed that such a cut will not be possible in the case of real data, so a realistic simulation should include them. Dan will consider what effects these might have on the final result.