1. ME0 ME0 Baseline – Design, Project Planning & Execution – Marcus Hohlmann Florida Institute of Technology Comprehensive Review – Phase 2 Muon Upgrade, CERN, June 28, 2016

2. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 2 Outline Motivation Performance requirements Status of baseline design Schedule, milestones, project planning Summary

3. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 3 ME0 muon detector in CMS 6 ME0 chambers Services for HGC/BH Backing Hadron Calorimeter (scintillator) High Granularity Calorimeter (silicon) elm. had. Services for ME0 New nose of CMS endcap:

4. ME0 MOTIVATION 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 4

5. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 5 Motivation for ME0 Extends muon coverage to |η| < 2.82 – Tags high-η tracks/calorimeter objects as muons – Increases acceptance for physics with muons, e.g. by ~ 20% for H → ZZ → 4µ channel Triggering muons with ME0 in its lower-η section 2.03 < |η| < 2.5 looks possible –GE1/1 covers up to |η| ~ 2.15 –ME0 restores muon trigger performance from |η| ~ 2.15 to full original muon endcap envelope of |η| ~ 2.5 HGCAL & BH Charge 2b

6. ME0 L1 muon candidate  Low magnetic field causes an explosive growth of the CSC muon L1 trigger rate towards high  –Mismeasured low-p T muons cause L1 rate to blow up Muon direction measurement with GE1/1  ME1/1 chambers decreases L1 rate substantially –But limited to the region |  | < 2.15 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 6 Trigger enhancement Charge 2b Solution: use ME0 stubs to repeat GE1/1 trick –This will restore L1 muon trigger capabilities in the entire original design envelope of |  | < 2.5 !

7. ME0 PERFORMANCE REQUIREMENTS ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 7

8. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 8 Minimal performance requirements Charge 3 Discriminate muons from n,  backgrounds –Find muon stubs among background hits at rates up to 30 kHz/cm 2 Handle overall particle rates comfortably (det. & electronics) –Expected max. tot. hit rate from simulation: 30 kHz/cm 2 (near |η| ~ 2.8) –Expected max. total chamber hit rate: 50-100 MHz Resolve hit positions about as well as GE1/1 –Azimuthal resolution: σ φ ~ 300 µrad –Radial (  ) resolution: σ r ~ 1-3 cm (  -dependent) (these estimates are starting points for simulation group; to be finalized) Resolve hit time sufficiently for clear BX association –Timing resolution: σ t < 8 ns Minimize discharges and aging effects –Survive for 10 HL-LHC years These requirements are the main drivers of the ME0 design ~

9. ME0 In analogy with the six-layer cathode strip chambers, six layers of ME0 chambers are expected to provide sufficient information to efficiently identify muon segments among background hits. 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 9 ME0 muon segments Muon hits Background hits Six ME0 chambers φ

10. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 10 Background flux & rate Now incorporates proper FLUKA treatment of HGCAL and BH in front of ME0 Max. flux in innermost ME0 section Particle flux Hit rate Convolute with ME0 sensitivity to different particle types using GEANT ME0 needs to handle a hit rate of 1- 30 kHz/cm 2 Charge 3

11. ME0 ME0 fulfills similar function for L1 muon trigger as does GE1/1 (stub bending measurement relative to ME1/1 CSCs) => Requirements for ME0 space and time resolutions are similar to those for GE1/1 –Resolve azimuthal position φ ME0 sufficiently for appropriate Δφ = φ ME0 -φ ME1/1 measurement (given the rate environment): Azimuthal resolution: σ φ_ME0 ~ 300 µrad Radial resolution: σ r ~ 1-3 cm –Resolve hit time sufficiently for clear BX association of hits: Timing resolution: σ t < 8 ns Exact specifications still under study with reconstruction and trigger simulations 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 11 Resolutions ~ Charge 3b

12. ME0 STATUS OF BASELINE DESIGN ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 12

13. ME0 Baseline: Triple-GEMs 6 layers of Triple-GEM chambers very similar to the GE1/1 chambers are expected to satisfy all minimum requirements and consequently constitute the baseline design for ME0: 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 13 Triple-GEM chamber (similar to GE1/1) ME0 stack: 6 layers of Triple-GEM chambers

14. ME0 ME0 baseline design closely follows the GE1/1 design: Triple-GEM detectors w/ 3/1/2/1 mm electrode gaps (as GE1/1) Coverage: 2.03 < |η| < 2.82 20-degree chambers (vs. 10-degree chambers for GE1/1) Chamber construction & assembly very similar to GE1/1 Chamber dimensions slightly smaller than GE1/1-S chamber 6 chambers in one ME0 stack (module) 18 stacks per endcap; 36 stacks total 216 chambers, 648 GEM foils required (50% more than GE1/1) 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 14 ME0 baseline design Charge 3d

15. ME0 Main constraints: endcap calorimeter constrains space available for placing ME0 chambers; limits number of ME0 layers to six layers no access after installation due to calorimeter services 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 15 Constraints on design 20.5 cm Charge 3c

16. ME0 6/28/2016 16 ME0 insertion into endcap nose In order to assure overlap between two adjacent detectors, stacks will be installed alternating front and back sides of stacks: M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN front back Charge 5

17. ME0 Detector overlaps 6/28/2016 17 ME0 chamber overlap Adjacent stacks overlap by 6.5 cm to ensure hermetic coverage M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN Charge 5

18. ME0 6/28/2016 18 Baseline electronics design ME0 baseline electronics design closely follows GE1/1 electronics design: Current design uses 8η × 3φ readout sections; exact segmentation under study, to be finalized 5184 (24 x 6 x 36) binary front-end chips (VFAT); 128 channels (strips) per VFAT 216 opto-hybrids w/ 24 VFAT inputs each 1 GEM Electronics Board (GEB) per chamber, 6 GEBs per stack; 216 GEBs total for ME0 system M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 24 VFAT 1 GEB One opto-hybrid per chamber readout section (128 strips) φ  Charge 5

19. ME0 Remaining design validation steps: –Confirm resilience against discharges The number of discharges is to be minimized Discharges that do occur should not have any ill effects on the long-term detector operation (non-destructive) –Accumulate sufficient charge in GIF++ aging test Need to accumulate 0.6 C/cm 2 while monitoring gain Completion of component design: –All component design closely follows GE1/1 design –Produce actual design drawings of components GEM foils, drift and readout PCBs, frames, GEBs, … 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 19 Validation & completion of baseline Charge 6

20. ME0  Accumulation of 450 discharges over a few cm 2. However, conditions quite different from those in CMS.  Observations:  Discharges are non-destructive  No impact on gain  Thin deposition of copper oxide in the irradiated region (all GEM foils)  Superficial copper etching near the rim of the holes  These do not affect the detector operation  In CMS, for ME0 we expect ~1.5 × 10 -5 discharges s -1 cm -2, or ~ 5 × 10 -5 discharges per second over a few cm 2, or one discharge every ~2 × 10 4 seconds over a few cm 2.  => The test corresponds roughly to 9 × 10 6 s of running in CMS, i.e. 15% of the total expected up-time of 6 × 10 7 s of the HL-LHC over 10 years. Caveat: There are large uncertainties in these estimates! Conclusion: Promising, but need to revisit estimates and do more tests to reach 10 HL-LHC equiv. years. If this indeed poses a problem, investigate mitigation. 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 20 Discharge test with Triple-GEMs Charge 6

21. ME0 Addressing the space constraint 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 21 R&D for baseline optimization ~ 18 mm ~ 40 mm ~ 18 mm Drift PCB RO PCB GEB Chimney housing services By coupling two adjacent chambers using a single double-sided drift PCB, it might be possible to remove three of the six PCB from the stacks and to reduce the stack thickness by about 6-10 mm. R&D for this back-to-back design (B2B) is ongoing with prototypes. drift gap chamber 1 chamber 2 Charge 5

22. ME0 6/28/2016 22 Back-to-back GEM rates Measurements performed on 10×10 cm 2 back-to-back prototype with 109 Cd source Placing the source in different positions (red markers below) on the active window to test the operation of the entire active area Both sections of the detector work properly reaching rate plateaus. M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN Charge 5

23. ME0 Preliminary results from run at H2 test beam: –Readout with four VFAT2 chips (40 MHz sampling) –Timing resolution ~10ns is comparable to GE1/1 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 23 Back-to-back GEM beam test Charge 5 Tracker GEM Tracker GEM Back-to-back GEM Ar/CO 2 70:30 Timing scintillator Time resolution (ns)

24. ME0 A first ME0 demonstration is essentially accomplished with a successful GE1/1 slice test since the ME0 design follows the GE1/1 design closely What remains to be done after that is the assembly of a complete ME0 stack fully integrated with electronics and all services 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 24 System demonstration Charge 6

25. ME0 Production steps are analogous to GE1/1 production: 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 25 Detector production steps ME0 stack Assembly

26. ME0 Tooling and setups (X-ray, copper boxes, cosmic ray stand) prepared for the GE1/1 production can be reused for ME0 production and tests. Crew trained for the production and test of the GE1/1 can easily move to the production and commissioning of the ME0 baseline detectors. Production sites “certified” for the production of GE1/1 chambers don’t need to be certified again. Production of ME0 modules can be seen as continuation of the GE1/1 and GE2/1 chamber production The new CMS GEM clean room, in preparation in bd. 904 (Prevessin) will be large enough to host the assembly of the ME0 stacks. 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 26 Detector production Charge 8

27. ME0 PROJECT PLANNING, SCHEDULE & MILESTONES ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 27

28. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 28 Complete ME0 Merlin schedule For reference only Charge 8

29. ME0 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 29 Schedule towards TDR Charge 8 2016 2017 TDR All R&D up to TDR

30. ME0 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 30 ME0 Production schedule Charge 8

31. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 31 Schedule drivers Detector production stages are staggered –Separate production lines for module assembly and assembly of final installation unit (GE1/1 superchamber; GE2/1 chamber; ME0 stack) Schedule drivers (stars indicates “conservative” estimates): –GE2/1 and ME0: module production followed by GEM foils Electronics development –Becomes a schedule driver if development beyond VFAT3 is needed Foil ProductionModulesSuper-Chambers (GE1/1)/ Chambers(GE2/1) / Stacks (ME0) Total Number VendorsYield per mo. per vendor Time (mos) Total Number Ass’y lines Yield per mo. per line Time (mos) Total number Ass’y lines Yield per mo. per line Time (mos) GE1/14321222014442.515721126 GE2/1864218*242884*2.529721612 ME0 648218* 18 2164*2.5 22 361312 Charge 8

32. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 32 ME0 high-level milestones Charge 8

33. ME0 Triple-GEM detectors constitute the ME0 baseline; they satisfy all basic performance requirements Remaining issues are experimental validation of resilience against aging and discharges The ME0 chamber and electronics designs follow the GE1/1 design very closely => We know how to build these detectors Main design constraints are from tight spaces and limited access in the muon endcap –R&D is being done to slim down chambers a bit ME0 detector production is anticipated to follow directly on heel of GE1/1 and GE2/1 production 6/28/2016 M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 33 Summary & Conclusions

34. ME0 Thank you! M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 34 6/28/2016

35. ME0 BACKUP 35 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN

36. ME0 6/28/2016M. Hohlmann, ME0 Baseline Detector Design, Comp. Review Phase 2 Muon Upgrade, CERN 36 Performance - big picture ME0GE2/1RE3-4/1 Performance Parameter Baseline requirement Additional requirement (option) 3-GEM FTM3-GEMµRWELLStd. RPC iRPCMRPC Rate capability 2 kHzn/a ok 90 kHz (SF3)ok n/a Trigger time resolution < 8nsok n/a < 2nsnookn/a ok < 100 psnomay be n/a no ok Trigger Bending angle Δ φ with CSCs φ resolution < 0.3mrad ok n/a Reconstructio n spatial resolution ≈ 400 µm ok n/a spatial resolution 0.8 – 1.7 mm n/a ok Operationeco-friendly gas ok no