Report on Working Group # 2 The MU2E detector S.Miscetti LNF INFN Frascati MUSE Scientific Board meeting 15-Sep-2017

Calorimeter: Status (1) PRE-Prod of Crystals completed PRE-Prod od MU2E SiPMs completed PRE-Prod of FEE preamplifier completed PRE-Prod of MB , NIM-version done  V1 design completed, in production x 5 PRE-Prod of WD. V1 design completed  First board in Pisa. V2 (versatile link + DCDC converter) under planning V3 (SmartFusion2  PolarFire ) being discussed FEE  WD cables being modified with better connector. Much more reliability  much higher cost Module-0 completed Test beam of Module-0 done Getting ready for slice test with all final components S. Miscetti | MUSE SB meeting 15 Sep 2017

FEE-MB + WD status First prototype (V1) of 20 ch digitizer done (DIRAC). Design of Mezzanine board 20 chs also completed. Production underway. Changes for digitizer V2: Optical drivers selected by Mu2e does not work after 4 krad TID  CERN Versatile Link ?? New DCDC converter (LTM8033  LTM8053). It has lower efficiency than LTM8033 but works up to 150 krad. Changes for digitizer V3: Only existing FPGA radiation tolerant at acceptable cost (350 Euro/each) was the Microsemi SmartFusion2  tested from tracker group. Not reprogrammable after 10 krad. Internal delay increases after 60 krad New family of FPGA Polarfire, disponibile Q4, works up to 600 krad  compatible cost. S. Miscetti | MUSE SB meeting 15 Sep 2017

Calorimeter: Status (2) CRR review for CsI and SiPMs done 19 June 2017  Comments/Recommendations received (0) Review the limit on energy resolution , hold (1) Measure SiPM outgassing, done (2) Perform a stress test of SiPMs, done DOE IPR-review done end of July Tender for crystals and SiPMs completed  2 vendors for CsI (Siccas, St.Gobain)  1 vendor for SiPM (Hamamatsu) PO are ready  production will start end of the year Preparation of QA site in progress at SIDET S. Miscetti | MUSE SB meeting 15 Sep 2017

SiPM Holder outgassing measurement 4 SiPM holders tested (2 HPK SiPMs, 2 FEE chips, Faraday cages/holders) Thermic glue used to join SIPMs to holders. Measurement were taken for almost 3 week  Heating for 72 hours at 45 °C. After 480 hours (20 days) We have reached: 1 x 10-5 mbar x liters/sec The final calorimeter system has about 1400 full-holders. Total SiPM/FEE contribution for outgassing is obtained as: Qtot1 = 1 x 10-5 mbar x liters/s x 1/4 (4 full-holders) x 1400 = 3,5 x 10-3 mbar x liters/sec Qtot = Qtot1 x 0.75 (Torr/mbar) = 2,6 x 10-3 Torr x liters/sec  Comparable with CsI outgassing S. Miscetti | MUSE SB meeting 15 Sep 2017

SiPM Thermal Test We have stressed the MPPC with thermal cycles between 20 and -10 ○C We used a Temperature Chamber in SiDet Lab-B borrowed for 1 week. 30 min per Thermal Cycle; Not relevant variation observed in the leakage current after 15 cycles. It will be part of our QA S. Miscetti | MUSE SB meeting 15 Sep 2017

QA assembly area at FNAL S. Miscetti | MUSE SB meeting 15 Sep 2017

Mechanics Preparation of tenders for Disk support + CF ring and plate. Tenders for crates, back disk (PEEK) and cooling in 2018. New version of SiPM holder exists. A lot of improvements. Plan is to have most of the pieces at end of 2018. Crystal and SiPM assembly beginning of 2019. S. Miscetti | MUSE SB meeting 15 Sep 2017

The Mu2e calorimeter deliverables D2.1 (Technical Design Report) Month 12 D3.3 (Design of the Mu2e Laser system) Month 18 D4.2 (Development of Mu2e simulation code) Month 32 D2.2 (Production DB for crystals and sensors) Month 36 D2.5 (Assembly of the first calorimeter disk ) Month 42 Delay on deliverable for Laser system. Still some delay but work has started. C. Ferrari and I had a great meeting last week. Designs/offers for bundle of fibers are ready  proto soon. Laser power calculated  5-10 uJ. 3 models under study. Distribution optics  few options under consideration. PIN-Diode with Corradi FEE being discussed. Working on a draft version in the coming weeks. S. Miscetti | MUSE SB meeting 15 Sep 2017