South Arm FEE Performance Prior to Au run, all FEMs installed and working. Currently, 157 of 168 FEMs read out useful data. = 93.5% operational FEM losses: station 1 = 4/40 = 10% station 2 = 4/64 = 6.25% station 3 = 3/64 = 4.7% add them up, square them to get dimuon acceptance loss due to bad FEMs ~37.5% Several additional FEMs have dead CPA or AMU chips. Some FEMs have isolated dead channels, no gain channels. Suspect most dead FEMs due to CLINK cables.

South Arm FEE Performance FEM pedestals: Pedestal (ADC counts) channe l Pedestal stability

South Arm FEE Performance FEM noise (goal was < 2 ADC counts rms) We have grounding + radiative components Station 2 ~ Station 3 ~ Station 1 ~ RMS noise

South Arm FEE Performance Calibration slope = gain gain response residuals (straight line fit)

South Arm FEE Performance Residuals (station 2) Octant test (cosmic rays) Au data

South Arm FEE Performance ARCNet: Ability to reprogram FPGA EEPROM via ARCNet has been tested and proven on south arm. FPGA coding: Need to address - five event buffering (currently have 4 event buffering) - first sample offset problem - speed of execution

South Arm HV Performance Chambers trained well after installation in winter. Problems appeared just before run in summer, appear to be strongly correlated with humidity. Dry air lines run to MMS around mid-September. Estimate ~15% additional dimuon acceptance loss due to HV. (total dimuon acceptance loss due to FEE and HV ~50%)

304 end of run South Arm HV Performance

South Arm Alignment System 54 of 56 light paths functional. 1 light path blocked 1 image out of view ~10  m precision azimuthal radial field off field on

South Arm Performance Station 2 peak cluster charge

South Arm Performance

Number of fitted clusters per cathode plane per event