Prototype activities update W. Baldini on behalf of the Ferrara IFR Group XXVII SuperB Workshop and Kick off Meeting Isola d’Elba May 28 - June 02 2011

Prototype activities in Ferrara After the Fermilab beam test the prototype has been shipped back and is now installed and running in Ferrara The configuration is the same as at Fermilab: Same Pizza Box configuration (CP1) Distances among PB are the same No Iron We are following the plan showed in Frascati in April: Taking cosmic data overnight with different working conditions (Vbias , thresolds ..) Improvements, debugging and other measurements during the day Pizza Boxes

Plans for cosmic data taking (from frascati meeting) At the very beginning triggering with the upper and lower-most layers, mainly for debugging purposes As soon as we reach a stable condition, switch to an external scintillator trigger and measure: Efficiency and time resolution for different SiPM bias voltages (to understand a strange behaviour of some PB @ the testbeam) Number of p.e./mip for the different combinations of scintillator-fibers-SiPM (at the testbeam not enough time…) Test the special module with MPPC (not tested at the Dic. testbeam) Comparison with testbeam data Done Done Ongoing Ongoing

Cosmic Data Taking schedule Date Filename Start Stop N evts Run # Comments May 11 FEEConfig_base Baseline conf. (G=14,17) May 12 FEEConfig_High_Gain High Gain (15,18) May 13 FEEConfig_High_Gain_2 High Gain (16,19) May 14 FEEConfig_AllV_32.75V All channel @ 32.75V May 15 FEEConfig_AllV_33.00V All channel @ 33.00V May 16 FEEConfig_AllV_33.25V All channel @ 33.25V May 17 FEEConfig_AllV_33.50V All channel @ 33.50V May 18 FEEConfig_AllV_33.75V All channel @ 33.75V May 19 FEEConfig_AllV_34.00V All channel @ 34.00V May 20 May 21 May 22 May 23 Pulser – th scan Random trigger May 24 May 25 May 26 Due to problems with the high temperature (up to 32 C) some runs have to be repeated see Gigi’s Talk on Tuesday

Light Yield measurement Measure how many p.e. we have for different options: Scint. 1 or 2 cm thickness WLS fibers 1.0 mm vs 1.2 mm in diameter SiPM 1.2x3.2 mm2 (4020) vs 1.4x3.8 mm2 (4380) The method is very simple: measurement of the gain (2pe – 1pe) on the Dark count spectra In the same conditions (Vbias,T) measure the average signal on cosmics, triggering on the other SiPM of the same scintillator, with a high threshold (5-6 pe). Npe= Average-signal/G

Light Yield Measurement: the method 1 pe 2 pe Gain Dark count (low Thr) Cosmic Signal (High Thr on other SiPM) signal pedestal Npe = (sig. – ped)/Gain

Light Yield Measurement: preliminary results Fiber length L=3.25m Fiber length L=0.75m Pizza box #1 (scint=2cm, fib=1.0mm, SiPM=4020 ) This are very preliminary results, high temperature (up to 32 °C, no air conditioning yet…)

Light Yield Measurement: next steps Measure the light yield for other configurations: PB #5 : fibers 1.2mm in diameter and SiPM 1.4x3.8mm2 PB with 1cm scintillator and Kuraray 1.0 and 1.2mm fibers Measure precisely the temperature dependence of Gain (and Dark Count rate) in order to make corrections on Vbias settings Test MPPC module (PB #7) and compare with SiPM

Preparation for the next testbeam Exploit the previous experience to optimize the next data taking: Cerenkov cables: prepare 75W  50W adapters larger S3,S4 scintillator Faster S1-S2 scintillator (or use the TOF) …. Other?? Cerenkov gas: check if the bottle is still full Understand how to reduce SiPM temperature on site Start shipping procedure…

Next main activities Testbeam in July-August (Ju;y 13-20 installation, July 20 – Aug 3 data taking Testbeam data analysis and comparison with MC simulations Radiation damage test (LNL or ENEA) : monitoring of current, Dark Count rate, Gain vs dose direct comparison unshielded/shielded devices comparison SiPM and MPPC Design of SiPM Mass Characterization setup TDR: collect all data and start writing