Radphi Video Conference 11/04/2003
continuation of 10/28/2003 call

November 4, 2003
University of Connecticut
Storrs, CT

Meeting Agenda:

1. Progress on kinematic fit - D. Krop
2. Progress on BGV calibration - D. Steiner
3. Remaining tasks for NIM paper - S. Teige
4. Research plans - M. Kornicer
5. Next meeting or workdays - R. Jones

• http://dustbunny.physics.indiana.edu/~teige/nim
• http://zeus.phys.uconn.edu/radphi/call-notes
• http://zeus.phys.uconn.edu/~kornicer/radphi/LGDresolution
• http://zeus.phys.uconn.edu/radphi/calibration/figs.html
• http://dustbunny.physics.indiana.edu/~dkrop/kinefit
• http://cabibbo.physics.wm.edu/~steiner/radphi

Present: R. Jones, M. Kornicer, D. Steiner, D. Armstrong, S. Teige, D. Krop

• On his web site he has posted 2 mass plots: one of 2 BGV clusters formed to an invariant mass and one of 1 BGV + 1 LGD. The former shows a clear π° peak, while the later shows no π° and a broad peak near 550 MeV. Perhaps this is the η split between forward and barrel, but there was some skepticism expressed about this. The 1-forward cluster sample is heavily biased by the trigger so it may not be the best place to look. R. Jones suggested that we look at the 3+1 sample and do 3 mass (1+1) combinations per event. In this sample we should clearly see the tail of the π° and on top there should be the η.
• Dan will send around a draft of a BGV calibration procedure that he will use to get the ADC gain. Richard suggested that he calibrate with separate gain on the different Z-segments of each BGV counter so as to extract by measurement the attenuation function for each block.

Scott needs some more input to finish the NIM article
• section on Lead glass radiation damage - D. Armstrong
• better electronics diagram - S. Teige
• section on LGD calibration, resolution - S. Teige + R. Jones

• Mihajlo proposed to study the reaction γp -> η' p in η' -> 4γ decays. He finds a 2% BR to γω. The main background will come from b1 and a2 decays in which some energy has been lost. This is a difficult channel. He will need the best resolution and kinematic fitter to find a signal. If he is unsuccessful, he will look at extending the work by D. Krop into new channels, π°η and ηη. This will require the BGV for efficient reconstruction.