Testbeam analysis on module #1 Lightyield calibration 2. Absorber studies 19/01/06 HCAL main meeting - Marius Groll

History of module #1 and setup features First produced module: suffered under debugging SiPMs: #35 -502 2MW quenching resistor bias voltage: 63 - 67 V ~ 60 long discharge candidates (30 with low frequency) Light coupling: prototype, no „reflector caps“ Use final VFE electronics (better protected DAC settings)  no unforced losses of DAC values (single user mode) No electronic temperature measurement No CMB: only stand-alone LED wo PIN readout 19/01/06 HCAL main meeting - Marius Groll

DESY test beam: 1st module test e-/e+ beam: 1-6 GeV VME crate very FE electronics beam trigger ~150 ns HCAL Module 1 NIM trigger logic 19/01/06 HCAL main meeting - Marius Groll

Calibration procedure SiPM Gain calibration with low intensity LED light MIP calibration of each tile with 3 GeV e- beam 0 pixel 1 pixel 2 pixels Noise spectrum Minimum ionizing energy gain / noise ~ 4 using ASIC chip in 2 modes: “calibration mode” “physics mode” short shaping time (40ns) longest shaping time (180 ns) highest gain medium gain 19/01/06 HCAL main meeting - Marius Groll

Uncertainty estimation Pedestal shift: mean value stable s = 5 ch (MIP ~ 250 ch)  no pedestal correction during data taking  use as systematic error Temperature corrections: big LED fluctuations: 25% NO Pin correction possible!  analog temperature measurement available: temperature in hall 2: 20 -22 °C  1°C = 3 s error on the meas. SiPM amplitude: 7% / 1 °C  2.5% temperature variation uncertainty Pedestal change in one week 176 19/01/06 HCAL main meeting - Marius Groll

LY calibration on module #1 197 ch. MIP average: 410 ADC ch +/- 18% Gain calibration MIP calibration Intercalibration Beam (sept. 05) LY: 13 pix/MIP, RMS 2 pix/MIP Tile tester (dec. 04) LY: 15 pix/MIP, RMS 2 pix/MIP Error on LY: 13.0 ± 0.3 ± 0.7 pix/MIP stat. syst.  D 1 pix/MIP due to temp. 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll Bug report Reasons for failed calibration: MIP fit failed: 19 channels Gain fit failed: 11 channels (Intercalibration failed: 16 channels  use Chip mean) in total: for 25 channels no LY calibration possible (out of which 5 dead channels) 19/01/06 HCAL main meeting - Marius Groll

Absorber studies on module #1 HCAL module 5x5 cm scintillator 1 X0 lead 3x3 cm scintillator with Hammatsu R5505 e+ 1-6 GeV Lead: RM = 0.9 cm X0 = 0.56 cm PMT1 PMT2 PMT3 Peter Smirnov and Yuri Soloviev Data has been taken in one week at the end of september Energy scan (e+ 2-6 GeV) PMT calibration wo absorber 1X0 shower data collected with 3 GeV beam  many entries at 1-3 MIPS  better determination of the lower part of the SiPM response function 5X0 shower data collected with 5 GeV beam  high amplitude (~30 MIPS)  SiPM non-linearity correction 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll MIP calibration and MC MIP calibration of PMTs Pedestal stable at the 1% level SiPM MIP calibration taken from runs before and after MC: standalone Geant3 with beam smearing: s beam = 1.5mm data before module PMT2 MC: s/mean = 0.08 Data: s/mean = 0.16  Good PMT resolution data after module PMT3 MC before module 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll PMT calibration and MC Leakage check with 5 X0 & MC comparison PMT2 & PMT3: non-linear behaviour at 5-6 GeV  ok Possible explanation: PMT2: leakage to the side (3x3cm2); checked with bigger 9x9cm2 scintillator SiPM data correction will follow! 19/01/06 HCAL main meeting - Marius Groll

Monte Carlo understanding MC work done by Y. Soloviev Geant 3 code Nice agreement in the PMTs  MC ok Disagreement for our module if no corrections are applied  non-linearity… Be aware! Shower fluctuation does not decrease with statistics. Approx. 30% energy spread 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll 1X0 analysis MC: PMT2: 5.9 MIPs SiPM: 6.5 MIPs SSIPM: 7.4 MIPS PMT3: 4.8 MIPs Data: chip 5 chan 13 PMT2: 6.2 MIPs SiPM: 6.8 MIPs SSIPM: 7.8 MIPs PMT3: 5.0 MIPs 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll 1X0 analysis But of course you have to do something before: ½ MIP cut  cut away SiPM noise Non-linearity correction Light xtalk correction  2.5% in agreement with ITEP meas. Long discharge handling PMT2 SIPM SSiPM PMT3 MC 5.9 6.5 7.4 4.8 >½ MIP cut 6.2 6.3 7.9 5.0 Linearity correction 6.8 8.5 Light xtalk correction 7.8 Long discharge w or w/o 2% difference in SSiPM  For 100000 events it seems to be not important 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll PMT2: plot explanation The following plots are done by dividing the data/MC into subsamples, which are determined by the numbers of MIP the PMT2 has seen 19/01/06 HCAL main meeting - Marius Groll

1X0 analysis: data MC comparison 19/01/06 HCAL main meeting - Marius Groll

1X0 analysis: data MC comparison SiPM central: wo linearity correction SiPM neighbours: wo xtalk correction 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll Summary: 1X0 analysis For 25 3x3 cm tiles: General agreement to MC only 5% spread between channels w/o any temperature & pedestals corrections Some physics: determination of lead moliere radius data: RM = 0.76 ± 0.07 cm MC: RM = 0.92 cm MC prediction 19/01/06 HCAL main meeting - Marius Groll

SiPM non-linearity correction Vassilly Morgunov correction proposal: comparison to Hendriks measurement in lab. correction maintained by LED measurements is too small; even after SiPM x-talk correction  open question 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll 5X0 @ 5 GeV analysis Electromagnetic shower maximum MC: PMT2: 30.3 MIPs SiPM: 25.9 MIPs SSIPM: 37.4 MIPS PMT3: 11.4 MIPs wo correction Data: chip 5 chan 9 PMT2: 30.0 MIPs SiPM: 20.7 MIPs SiPM_corrected: 26.2 MIPs SSiPM: 36.4 MIPs SSiPM_corrected: 39.9 MIPs PMT3: 10.9 MIPs w correction 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll 5X0 @ 5 GeV analysis Central tile/SiPM uncorrected Central tile/SiPM corrected 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll 5X0 analysis PMT2 SIPM SSiPM PMT3 MC 30.3 25.9 37.4 11.4 >½ MIP cut 30.0 20.7 36.4 10.9 Linearity correction 26.2 42.5 Light xtalk correction 39.9 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll MiniCal comparison SIPM SSiPM MiniCal 1X0 steal 3 GeV 7.4 8.1 Module 1 1X0 lead 3 GeV 6.8 7.8 MiniCal 5X0 steal 5 GeV 28.0 31.0 Module 1 5X0 lead 5 GeV 26.2 39.9 not completly possible to compare due to the different geometry: MiniCal: 5x5 cm tiles Module 1: 3x3 cm tiles  missing energy in MiniCal due to lateral leakage at the shower maximum  MC crosscheck is needed 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll Summary We have collected first beam data with our detector! We have learned a lot how to operate it and to collect data with the DAQ BUT: Next time minimisation of blind data taking time The importance of a good monitoring system is tremendous! Alternating data taking: data – led monitoring – pedestal is mandatory! Better knowledge of SiPM saturation curve with our electronics is needed Data correction procedure for SiPM non-linearity has to be improved 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll Backup 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll error bars = error on mean error bars = RMS 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll 5X0 analysis Analysis needs input for the correct SiPM response function correction MiniCal correction is doing for the first approximation a good job wo correction w correction 19/01/06 HCAL main meeting - Marius Groll

HCAL main meeting - Marius Groll 1X0 vs. noise black: shower red: noise 1X0 data have in the neighbouring tiles hit amplitudes comparable to noise hits 19/01/06 HCAL main meeting - Marius Groll