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

2. 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

3. 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

4. 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

5. 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 = 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

6. 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

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

8. 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

9. 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