# Minutes: Taskforce Meeting on CERN Testbeam Data (Feb. 23, 2023) ## Time: 11:00 → 12:30 (GMT+8) ## [indico page](https://indico.ihep.ac.cn/event/19006/) ## Participants (16) * IHEP: Baohua, Dejing, Hengyu, Yuzhi, Xin, Yong * SJTU: Francois, Haijun, Siyuan, Zhen, Zixun, Jiyuan * USTC: Hongbin, Jiaxuan, Yukun, Zixun * Tokyo: Ryonosuke, Tatsuki, Wataru (Chair and minutes by Yong) ## Talks and discussions ### Talk: ScEcal Preliminary analysis, by Xin Xia * Data set * 100GeV Positron ；ECAL_Run289_20221030_125331 * Method * Correlation of nTotalHits vs. energy deposition * Categorised events of 3 particle types: mu+/e+/pi+ * Cross checks with Druid display * Results * Based on the selected positron samples * Proportion of different particle components * EM energy resolution and linerity * Discussions * MC samples as guidance for the categorisation ### Talk: AHCAL MIP Calibration, by Zixun Xu * Muon data for AHCAL alone * Fitting function: Laudau+Gaussian Convolution * First fit at the chip level, then use the parameters as each channel’s initial parameters. * Fitting range:100-1500, minor adjustmentsmade to a small number of channels. * Results * Mapping of MIP peak vs channel ID for each layer * ~0.4% of channels failed in the fitting * Will need better fitting strategy for Layer38 and 39 ### Talk: Reconstruction ofShower Radius, by Ji-Yuan CHEN * Simulation: AHCAL alone * Method * Reconstruction of Shower Radius * 3 different definition for shower radius * Only hits info was used * Results * Distributions for MC: well separated for e/mu/pi * Plan * Implementations into PIDTool ### Talk: General Updates on Testbeam Simulation, by Baohua Qi * Simulation setup: AHCAL alone * Birks effect considered in simulations * Beam: mu+, e+, pi+ * Digitization: * Photon statistics * SiPM response * SiPM gain uncertainty * ADC error: assume 0.02% * ADC saturation: based on MIP data * Energy threshold: 0.3 MIP * Simulation of ADC, based on data * Baseline: ~400 ADC tics * High gain: ~300 ADC tics/MIP * Low gain: ~8 tics/MIP * HG ADC limit: saturated at ~2700 tics * Results * HG saturation: significant spread for all channels * Pion data vs MC: effects of HG-LG saturation positions in simulation * Implication: HG-LG inter-calibration per channel needs to be implemented in the data * Positron data vs MC (e+, pi+ and protons) * Significant discrepancies still * Implication: e.g. strong SiPM saturation effects -> needs SiPM non-linearity corrections ## AOB * Data sets and decoders (information from Mattermost * ECAL data set: directories * ``` /cefs/higgs/wangjx/BeamData/ECAL_Filename.txt``` * ECAL data decoder * ``` /cefs/higgs/wangjx/ScECAL/Diagnose/src ``` * HCAL data set: directories * ```/cefs/higgs/shiyk/Beam_2022/BeamData/HCAL/Particle/DatList.txt``` * HCAL data decoder * ```/cefs/higgs/shiyk/Beam_2022/Decode/HBUAna_Cherenkov``` * ECAL slcio files: ```/cefs/higgs/wanghengyu/cepc/Root2SLCIO/work/data/fast_lcio/ecal``` * which are converted from the raw files at, ```/cefs/higgs/wangjx/ScECAL/Result_Diagnose/calib```