1. ACD calibrations Pedestals Measured from online script Measure PHA w/ HV off, no charge injection Use cyclic triggers ~100-300 ADC counts, very narrow (rms 2-3 counts) Gains Measured from self-triggered data Look for MIP peak w/ HV on W/ full LAT use TKR extrapolation W/ ACD only use coincidence to reduce angular distribution

2. PHA distribution in a single channel MIP peak Low energy noise Seen in both PMT (probably x-rays in same shower as muon) Zero suppression is on for these data (15 cts above pedestal) Veto threshold (0.3 MIP)

3. Fitting the MIP peak To determine fit range 1)Find local min between low energy noise & MIP 2)Find MIP peak 3)Find ½ max value after MIP peak Fit between 1) and 3) Following procedure from ACD group, fit to polynomial Around MIP peak and Extract peak value

4. Robustness of fitting procedure Procedure is pretty robust for tiles. On first calibration run tried it only failed in 1 out of 178 PMTs. Need to pick a fallback option anyway. Ribbons don’t have a clear MIP peak Need more work on these

5. Scatter in MIP peak values