1. M. Alfonsi LNF/INFN Cagliari 5 May 2006 M1R1 mechanical requirements  Space constraint Frame and pannel Pads readout and trigger sectors Gas inlet and outlet  Low material budget Gem foils Honeycomb technology

2. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Beam Pipe The space around the beam pipe is the major constraint for the panel dimension and electronics construction

3. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Honeycomb gas outlet Cathode Panel gas fitting HV Panel GEM Chamber side view GEM Chamber top view G1G2G3 PADs Panel gas inlet 7 mm GEM Chamber Layout

4. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Mechanical detector design The cross section of a GEM Chamber Module Pads PCB Cathods PCB bushing

5. M. Alfonsi LNF/INFN Cagliari 5 May 2006 G10 FRAMES

6. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Frames layout Active area -Frame 3 mm - 7 mm Frame Width 18 mm – 30 mm Frame Thickness 1mm 2mm 3mm 6 holes for decoupling resistors 4 hole pins Two glue roads (1 per size) Glue road wide 6 mm

7. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Position Frame Thickness Frame+glue Thickness xx 12,993,020,03 22,993,080,09 32,993,000,01 42,922,960,04 52,952,980,03 62,982,990,01 73,003,040,04 83,043,050,01 92,962,980,02 102,963,000,04 112,952,970,02 122.962.980.02 mm2.98±0.033.00±0.040.03±0.02 1 23 4 5 6 7 89 10 11 12 Glued-Frame Planarity Glue thickness 20  m Frame thickness rms 30  m

8. M. Alfonsi LNF/INFN Cagliari 5 May 2006 GEM FOILS

9. M. Alfonsi LNF/INFN Cagliari 5 May 2006 The GEM Foil layout 200 mm 240 mm 34 mm Holes for SMD decoupling resistor G10 Frame

10. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Gem Layout G1 Three different type of GEM foils Difference only for final HV electrodes 6 sectors for a total active area of 200 x 240 mm 2

11. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Gem Layout G2 The sectors towards the cathode

12. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Gem Layout G3 References for frame gluing

13. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Sag measurements Different loads on the 40x40 cm 2 GEM foils have been applied : 80 g, 160 g, 240 g Measurements on 25 points 30 Kg/side

14. M. Alfonsi LNF/INFN Cagliari 5 May 2006 GEM sag measurements The GEM foil with a stretching of 30 Kg per side (~1Kg/cm) shows a bending of 100  m on central region when a distributed load of 100 g is applied, equivalent to a pressure of 0.1 mbar. The electric field produce a load of ~ 0.01 mbar. The total bending due to an electrostatic load should be of the order 10  m. The LHCb triple GEM detector is built without spacers 80g 160 g 240g 0 g

15. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Kapton Radiation Hardness C= 251 pF C= 277 pF C= 234 pF C= 266 pF  C = 32 pF  d>= 120  m After Aging  C = 26 pF  d>= 94  m Before Aging After aging a sag increase of 30  m corresponding to3  m in normal condition after 4 LHCb years Mechanical load 10 times the electrostatic pressure

16. M. Alfonsi LNF/INFN Cagliari 5 May 2006 HONEYCOMB PANELS

17. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Honeycomb Panels Pad Panel Cathode Panel 192 pads Gas outlet Gas inlet

18. M. Alfonsi LNF/INFN Cagliari 5 May 2006 machined reference ALCOA plane Honeycomb panel technology back-plane: (1 mm) FR4 – single side (12  m) Cu vacuum bag 3M–epoxy film Cathode/Pad-PCB: (1 mm) FR4 gas insert 8 mm NOMEX honeycomb

19. M. Alfonsi LNF/INFN Cagliari 5 May 2006 PCB and 3M film The PCB are prepared : Cathod PCB Pads PCB appling the 3M film after gluing the gas inserts on PCB before

20. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Honeycomb The honeycomb is placed on top of 3M film cutting the nomex in corrispondance of gas insert and pins Gas insert : Stesalite and alluminum Alcoa frames Pins The backplane with a 3M film is put on top of Nomex and everything is put in a oven at 80°C

21. M. Alfonsi LNF/INFN Cagliari 5 May 2006 All panels will be checked for planarity with a 3-D machine at LNF. The measurements will be performed on a grid of 35 points. 3-D machine 5 10 15 20 25 30 35 4 9 14 19 24 29 34 3 8 13 18 23 28 33 2 7 12 17 22 27 32 1 6 11 16 21 26 31 Panel Planarity Measurements Measurement points

22. M. Alfonsi LNF/INFN Cagliari 5 May 2006 3 Pad panels3 Cathode panels Panel Measurement Thickness rms 35  m Thickness rms 23  m

23. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Pads layout Trigger sector

24. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Detector (“single gap”) performances with ground lines between pads are better than those obtained 0.6 mm 0.4 mm Pad-PCB layout No Aging effect on pads !

25. M. Alfonsi LNF/INFN Cagliari 5 May 2006 Detail on GEM Chamber

26. M. Alfonsi LNF/INFN Cagliari 5 May 2006 PAD ->36 μm Cu 1.43 cm0.25 % 2 mm G10 19.4 cm1.03 % 18 μm Cu 1.43 cm0.13 %1.42% X° 1 μm Ni 1.42 cm0.007 % 0.15 μm Au 0.33 cm0.005 % GEM ->10 μm Cu x3 1.43 cm0.21 %0.26% X° 50 μm kapton x3 28.6 cm0.05 % CAT -> 0.15 μm Au 0.33 cm0.005 % 1 μm Ni 1.42 cm0.007 % 18 μm Cu 1.43 cm0.13 %1.42% X° 2 mm G10 19.4 cm1.03 % 36 μm Cu 1.43 cm0.25 % 3.10% Globally  3.1 x 2 (ch.s) = 6.2 % + 1% (FEE uniformely spread ) = 7.2% Detector Material Budget