1. Patrick PONSOT for the CEA-Saclay-Irfu group: F.Bauer, P.Daniel-Thomas, E.Ferrer-Ribas, Ch.Flouzat, J.Galan, W.Gamache, A.Giganon, P-F.Giraud, P.Graffin, S.Herlant, S.Hervé, F.Jeanneau, H.LeProvost, O.Meunier, A.Peyaud, Ph.Schune ATLAS-NSW FRASCATI MMM WORKSHOP SACLAY PLAN 29-30th of November 2012

2. OUTLINE 2012/11/29-30 | 2 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Design ideas Saclay’s baseline / size of the wedges (quadruplets) Possible mechanical design of a quadruplet Dedicated frame to fix the mesh and the drift electrode Positioning of the doublets Alignable ? Materials Proposal to build an operational quadruplet Learning about procedures (gluing, positioning,…etc.) Checking all parameters (precision, in-plane alignment, electronics, RO mapping, services…etc.) Assembly ideas Assembly procedure of the quadruplets (some remarks) Assembly of the quadruplets to form a wedge, a station, a sector ? In-plane alignment ? Mechanical prototypes and task sharing Objectives -Control of the geometry (precision of the construction) -Control of the deformation (in-plane alignment) Behavior of a doublet (with and without pillars) ? FEA - Thermo-mechanical simulations Schedule and sharing of work

3. OUTLINE 2012/11/29-30 | 3 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Design ideas Saclay’s baseline / size of the wedges (quadruplets) Possible mechanical design of a quadruplet Dedicated frame to fix the mesh and the drift electrode Positioning of the doublets Alignable ? Materials Proposal to build an operational quadruplet Learning about procedures (gluing, positioning,…etc.) Checking all parameters (precision, in-plane alignment, electronics, RO mapping, services…etc.) Assembly ideas Assembly procedure of the quadruplets (some remarks) Assembly of the quadruplets to form a wedge, a station, a sector ? In-plane alignment ? Mechanical prototypes and task sharing Objectives -Control of the geometry (precision of the construction) -Control of the deformation (in-plane alignment) Behavior of a doublet (with and without pillars) ? FEA - Thermo-mechanical simulations Schedule and sharing of work

4. INTRODUCTION 2012/11/29-30 | 4 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT A report has been written to describe the Saclay’s plan for the mechanical architecture of the micromegas wedges

5. DESIGN IDEAS 2012/11/29-30 | 5 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Saclay’s baseline = 2 Wedges made of 4 Modules with maximum size ~2m 2 As reminder : MM Module = Quadruplet = 4 planes in Z direction Why ? We think that it is not possible to reach the perpendicular required precision of the strips by assembly of 4 planes with a very large area (large sector ~6m 2 ) -In spite of a lot work, we never reached this range of precision during the construction of the ALICE muon panels (carbon fibers panels) -Using our experience on CTA mirror (very recent tests), we think that we can reach the precision for a 2m 2 area At the end we need :  MM < 100  m (micro-TPC mode) strip parallelism: ≤ 40  m Mechanical precision perpendicular to strip plane: <150  m at 15° (inner quadruplets) < 80  m at 30° (outer quadruplets) Very complicated to realize the 2D read-out mapping and to connect the Y strips through the full length of the wedge (~3.7m) Views on next slides

6. DESIGN IDEAS 2012/11/29-30 | 6 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Saclay’s baseline = 2 Wedges made of 4 Modules with maximum size ~2m 2 As reminder : MM Module = Quadruplet = 4 planes in Z direction Why ? From our experience: MM Compass (G10) Alice / Carbon panels MM T2K (G10) CTA mirrors (Carbon, G10, Al.)

7. DESIGN IDEAS 2012/11/29-30 | 7 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Possible mechanical design of a quadruplet (scheme) Central panel is the mechanical support (thickness at least 20mm to define by FEA, and to test with prototypes) At least ~75mm At least ~20mm Fixation (and gluing?) of the mesh frame Possible to put an interface to connect the supports Assembly of the quadruplet after positioning of the 2 doublets Mechanical reference system to position the 2 doublets (metallic inserts) This part of the central panel can be local or all along the sector If needed, pillars Doublet (Not up to date)

8. DESIGN IDEAS 2012/11/29-30 | 8 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Possible mechanical design of a quadruplet (scheme) Supporting of 2 quadruplets, in-plane alignment system → Local links (to confirm by FEA) In plane alignment to connect the 2 quadruplets Local supports ~75mm At least ~225mm The 2 MM wedges are linked by local supports (kinematic links) Bar support to link the 4 modules (Not up to date)

9. DESIGN IDEAS 2012/11/29-30 | 9 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Possible mechanical design of a quadruplet (scheme) Supporting of 2 quadruplets, in-plane alignment system → If local links are not enough, by using a spacer-frame In plane alignment to connect the 2 quadruplets The 3 kinematics supports can be fixed on the spacer-frame At least ~225mm The 2 MM wedges are linked by a spacer-frame (kinematic links, holes to have access to the electronic) ~75mm (Not up to date)

10. DESIGN IDEAS 2012/11/29-30 | 10 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Possible mechanical design of a quadruplet (scheme) Dedicated frame to fix the drift cathode and the mesh ? A transfer frame can be used for mounting Fixation (and gluing?) of the mesh frame Cathode made of kapton or mylar + Copper or al. Mesh Transfer frame to maintain the tension inside the mesh and cathode (Not up to date)

11. DESIGN IDEAS 2012/11/29-30 | 11 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Possible mechanical design of a quadruplet (scheme) Positioning of the 2 doublets By using metallic inserts glued with high precision during the construction of the doublets Targets reference on PCBs to glue the inserts and to check the alignment of the 2 doublets Z positioning of the doublets is done also by using the inserts (on doublets and on central panel, precise thickness) Mechanical reference system to position the 2 doublets (metallic inserts) Assembly of the quadruplet after positioning of the 2 doublets (Not up to date)

12. DESIGN IDEAS 2012/11/29-30 | 12 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Possible mechanical design of a quadruplet (scheme) Alignable (in-plane alignment is on the outside panel) ? How can we guaranty that the stiffness of the doublets is enough to control the Z position of the strips inside a quadruplet (// of the doublets after deformation due to thermo-mechanical loading) ? Testing is needed to know the relative deformation of each panel inside a quadruplet If result is negative, pillars (or other spacer) should be glued in the drift gap (40 pillars diameter 5mm is less than 0.2% of the detection area) More difficult to glue the pillars with separate mesh (no bulk), and with separate drift cathode If needed, pillars 5 mm Gluing on few additional and larger pillars ? 5 mm // strips No bulk Bulk Deformation with thermal loading is not symmetric (Not up to date)

13. DESIGN IDEAS 2012/11/29-30 | 13 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Possible mechanical design of a quadruplet (scheme) → Materials Honeycomb should be perforated (or porous) to use the vacuum pumping for gluing MaterialsMass density (g/cm 3 ) Young modulus (Gpa) CTE (ppm/°C) G10/FR4(Epoxy-glass)1.9~1710-20 Copper8.9~12016-17 Honeycomb (6mm) - “paper”~0.032 Honeycomb (6mm) - aluminum (50µm perforated) ~0.040~7623 Pyralux PC1025 (photoimagable film)tbdtbd (global test of PCBs)100-130 Tensile tests in 3 directions to evaluate the Young modulus of the PCBs has been done at Saclay -L (length direction) → 24 Gpa -l (width direction) → 21 Gpa -p (45°) → 17 Gpa Very important parameter : ageing of the material should be studied before to use them (e.g. zebra connectors are made of silicon elastomer which has a bad withstand to radiation)

14. OUTLINE 2012/11/29-30 | 14 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Design ideas Saclay’s baseline / size of the wedges (quadruplets) Possible mechanical design of a quadruplet Dedicated frame to fix the mesh and the drift electrode Positioning of the doublets Alignable ? Materials Proposal to build an operational quadruplet Learning about procedures (gluing, positioning,…etc.) Checking all parameters (precision, in-plane alignment, electronics, RO mapping, services…etc.) Assembly ideas Assembly procedure of the quadruplets (some remarks) Assembly of the quadruplets to form a wedge, a station, a sector ? In-plane alignment ? Mechanical prototypes and task sharing Objectives -Control of the geometry (precision of the construction) -Control of the deformation (in-plane alignment) Behavior of a doublet (with and without pillars) ? FEA - Thermo-mechanical simulations Schedule and sharing of work

15. PROPOSAL TO BUILD A QUADRUPLET 2012/11/29-30 | 15 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Building an operational quadruplet (~1m x ~0.5m) within the collaboration Not a critical milestone But necessary part of the Saclay’s development plan to prove to the CEA-Saclay-Irfu management team that the assembly of 4 MM planes will be completely understood before the construction of a module zero (to get resources to prepare the production) Objectives Learning about procedures (gluing, positioning,…etc.) Checking all parameters (precision, in-plane alignment, electronics, RO mapping, services…etc.) Testing inside a precise cosmic bench

16. PROPOSAL TO BUILD A QUADRUPLET 2012/11/29-30 | 16 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Building an operational quadruplet (~1m x ~0,5m) within the collaboration Not a critical milestone This prototype will allow checking of the: design and manufacturing of the components assembly procedure mechanical precision in-plane alignment method 2D read-out mapping electronics implementation cosmic tests services (HV, gas, …) … To be discussed within the collaboration: Tasks sharing within the collaboration Parallel testing ? Using of existing precise cosmic bench

17. OUTLINE 2012/11/29-30 | 17 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Design ideas Saclay’s baseline / size of the wedges (quadruplets) Possible mechanical design of a quadruplet Dedicated frame to fix the mesh and the drift electrode Positioning of the doublets Alignable ? Materials Proposal to build an operational quadruplet Learning about procedures (gluing, positioning,…etc.) Checking all parameters (precision, in-plane alignment, electronics, RO mapping, services…etc.) Assembly ideas Assembly procedure of the quadruplets (some remarks) Assembly of the quadruplets to form a wedge, a station, a sector ? In-plane alignment ? Mechanical prototypes and task sharing Objectives -Control of the geometry (precision of the construction) -Control of the deformation (in-plane alignment) Behavior of a doublet (with and without pillars) ? FEA - Thermo-mechanical simulations Schedule and sharing of work

18. ASSEMBLY IDEAS 2012/11/29-30 | 18 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Assembly procedure of the quadruplets (some remarks) Due to experience of the institutes, we think that it is accessible to define precise tooling and procedures to build and to align the components but we will use a new material → large PCBs made of composite materials: G10, pyralux, copper…etc. Gluing procedure by using vacuum should be tested with real PCBs as soon as possible to answer to the following questions : -What is the best choice for materials to control the geometry during the production (stability, reproducibility) ? -Will the PCBs follow the granite table flatness ? -Will the PCBs stay flat after gluing of the honeycomb (temperature and humidity inside the cleaning room to do the gluing) ? -Do we get the // for the doublets by using the stiffback ?

19. ASSEMBLY IDEAS 2012/11/29-30 | 19 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Assembly procedure of the quadruplets or wedges (some remarks) A preliminary study has been done to evaluate the infrastructures and tooling that is needed to build quadruplets The building of the second ring of quadruplets has been used as main hypothesis to do this study We need a large cleaning room to do all the steps (2 gluing tables, 3 assembly tables) Unfortunately, the Saclay’s cleaning rooms are not available on 2013-2014. And we are not sure to get a new one. The construction of the operational quadruplet prototype will influence also the final decision We need one year to create a new cleaning room It is very important to take in account the infrastructures that we need to define the size of the modules that we can build (wedges ~6m 2 or quadruplets ~2m 2 ) May be the assembly should be done at CERN in a large cleaning room with participation of institutes Preliminary study to define a new infrastructure

20. ASSEMBLY IDEAS 2012/11/29-30 | 20 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Assembly of quadruplets to form a wedge, a station, a sector ? MM Wedges vs MM quadruplets sTGC wedges can be added with the same principle 3 kinematic supports to fixe the 2 wedges 3 kinematic supports to fixe the spacer-frame ~5.87m 2 ~1.89 m 2 ~1.85 m 2 ~1.33 m 2 ~0.80 m 2

21. ASSEMBLY IDEAS 2012/11/29-30 | 21 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT In-plane alignment system To be defined with specialists In-plane with 2 functions (to follow the 2 wedges) 3 kinematic supports to fixe the 2 wedges 3 kinematic supports to fixe the spacer-frame

22. OUTLINE 2012/11/29-30 | 22 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Design ideas Saclay’s baseline / size of the wedges (quadruplets) Possible mechanical design of a quadruplet Dedicated frame to fix the mesh and the drift electrode Positioning of the doublets Alignable ? Materials Proposal to build an operational quadruplet Learning about procedures (gluing, positioning,…etc.) Checking all parameters (precision, in-plane alignment, electronics, RO mapping, services…etc.) Assembly ideas Assembly procedure of the quadruplets (some remarks) Assembly of the quadruplets to form a wedge, a station, a sector ? In-plane alignment ? Mechanical prototypes and task sharing Objectives -Control of the geometry (precision of the construction) -Control of the deformation (in-plane alignment) Behavior of a doublet (with and without pillars) ? FEA - Thermo-mechanical simulations Schedule and sharing of work

23. MECHANICAL PROTOTYPES 2012/11/29-30 | 23 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Objectives Control of the geometry (precision of the construction) Control of the deformation (to define the in-plane alignment) Study of the geometry of a doublet Stiffness of the composite panel (PCBs + honeycombs + frames) Gluing test of 2 PCBs on the honeycomb (vacuum) Using of a composite stiffback Saclay’s plan: -Gluing of honeycomb on standard PCBs to evaluate the stiffness of a support panel -Gluing of honeycomb on large MM PCBs (paper honeycomb, perforated aluminum honeycomb…etc.) Options: -Sharing of the tasks and parallel testing with real PCBs (bulk & no bulk ?)

24. MECHANICAL PROTOTYPES 2012/11/29-30 | 24 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Study of the deformation of a quadruplet FEA to predict the deformations: to choose the size of the mechanical prototype Measurement without and with pillars Mechanical and thermal loadings Saclay’s plan: -Construction of mechanical structure equivalent to a MM doublet (G10 + honeycomb) -Dismountable to test without and with pillars -Holes in the external panels allow mechanical measurements on the central panel -Assembly with and without expandable pins to study the effect of the sliding of the frames Options: -To build an equivalent quadruplet (5 panels) -To build an assembly of 2 doublets (2x3 panels) -To use other materials (e.g. aluminum honeycomb, PCBs…etc.)

25. Study of the gluing of pillars Qualification of the gluing Choice of material for the pillars (Macor, peek…) Saclay’s plan: -Tooling is under manufacturing -200 pillars have been ordered (Macor, peek, different geometry to put the glue) Options: -Testing of other solutions and materials to guarantee a similar behavior of each MM plane after stacking MECHANICAL PROTOTYPES 2012/11/29-30 | 25 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT

26. MECHANICAL PROTOTYPES 2012/11/29-30 | 26 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Study of the positioning inside a quadruplet As described on slide 11 (positioning of the 2 doublets) Saclay’s plan: -Building of a simplified quadruplet (e.g. with the doublets created during other tests) Options: -Parallel testing -Other solution such as optical systems sTGC proposal

27. THERMO-MECHANICAL SIMULATIONS 2012/11/29-30 | 27 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT FEA analysis Preliminary FEA analysis have been done to: -provide arguments in order to make a decision concerning the layout -Identify the main cause of irregular deformation → thermal loading We need engineering models to: -Confirm that we can control the geometry with the alignment system according to the different options (quadruplets, wedges, stations, sectors…) Thermal expansion MM+sTGC ~100µm Temperature gradient 2°C ~50µm

28. THERMO-MECHANICAL SIMULATIONS 2012/11/29-30 | 28 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT FEA analysis Preliminary study of the behavior of a mixed sector (sTGC wedges + MM quadruplets fixed on a spacer frame) w.r.t. the position on the small wheel In this case, MM deformation is around ~100µm Vertical sector Horizontal sector Sector at 45° If we are not able to measure this type of deformation with the alignment system, we must guaranty that we will stay under these 100µm

29. SCHEDULE AND SHARING OF WORK 2012/11/29-30 | 29 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Preliminary schedule Help from collaboration is needed and is welcome : Task and cost sharing To participate to this program and/or to complete it

30. CONCLUSION 2012/11/29-30 | 30 Frascati MMM workshop - CEA-Saclay/DSM/Irfu - Patrick PONSOT Sharing of work and parallel testing within the collaboration are welcome to cover this plan as soon as possible Mechanical tests FEA analysis Operational quadruplet In-plane alignment Assembly of the quadruplets or wedges The largest cleaning rooms at Saclay will not be available on 2013-2014 The possibility to use a cleaning room at CERN should be evaluate

31. DSM Irfu SIS/LCAP (PC N°12, Bt 123) Patrick PONSOT Commissariat à l’énergie atomique et aux énergies alternatives Centre de Saclay | 91191 Gif-sur-Yvette Cedex T. +33 (0)1 69 08 79 30 | F. +33 (0)1 69 08 89 47 Etablissement public à caractère industriel et commercial | RCS Paris B 775 685 019 2012/11/29-30 Thank you for your attention ! Frascati MMM workshop - CEA- Saclay/DSM/Irfu - Patrick PONSOT | PAGE 31