CALO Meeting–September 2 nd 2015 Calorimeter Upgrade Electronics: June 2015 Test Beam E. Picatoste Universitat de Barcelona, Institut de Ciències del Cosmos ICC-UB

2 Objectives of the test beam Validate the ICECAL with channel+PMT+clipping+cable: Main measurements: 1)Linearity 2)Noise 3)Plateau and Spill Over 2nd September 2015CALO Meeting

Test Beam 3 CALO Meeting When: July 2015 Beam line: T4-H8 at CERN Prevessin Beam: e - with energy ranging from 20 to 120 GeV Elements used: 4x(ECAL module+PMT+12m cable) FEB prototype Lecroy integrator Time-to-Digital Converter (TDC) ICECALv3 ASIC 2nd September 2015

Setup 4 CALO Meeting2nd September 2015 Beam Scintillators Modules Adapted “T” TDC Lecroy Integrator VME TDC Lecroy Integrator VME PC CAT PC Merged files Trigger NIM Coincidence 40 MHz clock Busy Trigger Clock sinchronous trigger

Electron purity 5 CALO Meeting Targets used: Pb 6mm (initial configuration) Pb 12mm (final configuration) Electron purity improved after changing target Low electron purity affected measurements Difficult to analize for higher E 2nd September 2015

Linearity 6 Linearity: – With and without “T” – PMT gain not nominal Values: – Error due to low e- purity CALO Meeting2nd September 2015 Low e- purity

Plateau and spill over 7 Check different pole-zero configurations around optimal lab values. – Clipped signal – Non-clipped signal Specifications: – Plateau: signal stable in ± 2 ns (< 1% variation) – Spill over values < 1% in clock cycles before and after Plot and analyze signal vs TDC for different particle arrival time: – e- low purity difficults the analysis – Merge data files (with same conditions) – Under study CALO Meeting2nd September 2015

Plateau example 8 CALO Meeting2nd September 2015 Particle relative time of arrival (ns) ADC counts (pedestal subtraction) % signal 99% limit > 4 ns

Noise 9 Check noise in different conditions: o With “T” o No “T” o Clip o No clip Spec: ~1 ADC count Measured noise at lab without cable at the input: –1.4 ADC counts –1.7 ADC counts with pedestal subtraction CW switching noise? – Noise levels: o 12 LSB o 2.7 LSB (pedestal subtraction) – Correlated noise – Need to measure at detector level → check shut downs CALO Meeting2nd September 2015 ADC counts (ch 4) ADC counts (ch 6)

10 Outlook Statistics: –Low e- purity → difficult curve fits for measurements –Merged run data files to be analyzed Linearity seems OK Plateau and spill over –Plateau is over 4 ns –Spill over results is not well understood → to be checked Noise levels: –Looks like CW noise is high: 12 LSB and 2.7 LSB (ped sub) –Repeat measurements at the detector 2nd September 2015CALO Meeting