Robert Hance, Abilene Christian University / Brookhaven National LabTitle: Fine Tuning Electronics on the Crystal Ball Experiment at BNLAuthors: R. Hance, D. Isenhower, Crystal Ball Collaboration: ACU, ANL, ASU, BNL, GWU, KSU, PNPI, RBI, UCLA, UCol, UKa, UMD, UReg, ValUAbstract: A new Baryon Spectroscopy program has been initiated at the Brookhaven AGS facility with the Crystal Ball Spectrometer.This spectrometer, which consists of 672 NaI(Tl) crystals covering most of a 4p geometry, was originally built for studies of the excited charmonium spectrum at SLAC, and also used later at DESY. The excellent photon detection capabilities of this detector will allow the measurement of the coupling to neutral states not measured before in the field of Baryon Spectroscopy. The signal from each NaI crystal originates in a photomultiplier tube and then proceeds to an Integrate and Hold (I/H) module. Each I/H module receives nine signals which are split into a high gain and low gain amplifier and then multiplexed and transferred into one analog to digital converter (ADC). Since all eighteen channels are read out by a single ADC, problems were encountered in 1997 due to voltage offsets arising from several sources within the I/H modules. Each of the eighteen channels in the I/H modules had to have every component of these offsets measured and to be calibrated so that all eighteen channels matched. |