GEM Chamber 20x24 cm2
Status Report
 20x24 Prototype
F.Murtas for the GEM group
 PSI Test Beam
 Module 0 Progress
 Material budget
 Conclusions
F. Murtas LNF/INFN
9 July 2002
20 x 24 GEM FRAMES
We have preformed several trials
with Araldite glues :
Type
working time 50% hardness
Ciba 2010 15 min
3h
Ciba 2011 120 min
10 h
Ciba 2012
5 min
2h
1 frame glued with 2011
2 frames glued with 2012
The frame with glue is placed
on top of the streched gem foil
and pressed.
After 2 hours the frame is ready.
F. Murtas LNF/INFN
9 July 2002
PROTOTIPE ASSEMBLING
The three Gem frames are
placed on top of the others
without spacers...
.. and finally
the cathode
F. Murtas LNF/INFN
9 July 2002
PROTO @ PSI TEST BEAM
2 chambers 20x24 with
different geometry:
 3-1-2-1 mm
 2-2-2-1 mm
Total current of 27 mA on pads
27 mA
with divider
14 mA
with 7 independent hv channel
F. Murtas LNF/INFN
detailed analysis next meeting
9 July 2002
MODULE 0 : NEW GEM FOIL
Holes for SMD decupling resistor
G10 Frame
34 mm
240 mm
200 mm
F. Murtas LNF/INFN
9 July 2002
MODULE 0 : FRAME DESIGN
Glue “Rail”
G10 frames of 1-2-3 mm of thickness
5mm
Frame profile
Glue Ciba 2012
Holes for SMD decupling resistors
Glue for the next frame
Kapton foil
F. Murtas LNF/INFN
9 July 2002
BREAKING LOAD
Frame prototype
~ 1 Kg/cm
Kapton foil
~ 8 Kg/cm !
F. Murtas LNF/INFN
9 July 2002
GEM FRAMES PILEUP
HV
240 mm
200 mm
F. Murtas LNF/INFN
9 July 2002
MODULE 0 : PCB PAD
Next week test with foam
5 ASDQ
cards
connector
Gas inlet holes
7 ASDQ cards connector
F. Murtas LNF/INFN
9 July 2002
MODULE 0 : PCB CATHOD
ready in 3 weeks
Cathod
22
200 x 240 mm
36
4
45
10
GEM frame
34
HV connector for divider
F. Murtas LNF/INFN
9 July 2002
DOUBLE CHAMBER LAYOUT
side view
top view
FEE
Honeycomb
or foam
HV
A
gas fitting
G3
G2
G1 F
hv divider
B
gas inlet
gas outlet
HV
FEE
F. Murtas LNF/INFN
9 July 2002
MATERIAL BUDGET
Material budget for one GEM chamber
2 MWPC Pannels with:
- 1 PCB Pad . . . . . . . . . G10 1.6 mm of thikness and 35 mm Cu
- 1 PCB Cathod . . . . . . G10 1.6 mm of thikness and 35 mm Cu
- 1 Ground/shielding . . G10 1.6 mm of thikness and 35 mm Cu
3 Frames of 22 mm wide (36 mm for only one side) 1-3 mm thick
3 Gem Foils
. . . . . . . 50 mm Kapton and 5+5 mm Cu
F. Murtas LNF/INFN
2-3%
1% X0
0.5%
0.2 % X0
Total
Double Gem Chamber about 16%
5-6% X0
7-8 % X0
4%
8 % X0 (only detector )
9 July 2002
CONCLUSIONS
The 20x24 cm2 prototype has been tested at PSI
some hv instabilities with independent hv chnnels
with divider (final solution) seems much better
Final results on next meeting
Module 0 design and tools construction is going on
Material budget : X0 foreseen ~ 16%
8% (only detector)
 Module 0 ready for the end of Semptember
F. Murtas LNF/INFN
9 July 2002
210
204
240
246
20
34
6
26
31
34
4
3
7
36
6
8
15
22
8
20
schema cornice
tutte linguette di connessione da 6 mm di larghezza
bus di alta tensione e’ da 4 mm di larghezza
F. Murtas LNF/INFN
9 July 2002
Il foglio di kapton su cui e’ disegnato circuito deve avere dimensioni 340 x 340 mm.
Il circuito che ha dimensioni 210 x 304 deve essere centrato com in figura
36
210
204
65
65
240
246
20
34
6
26
7
31
34
4
3
8
15
20
340
F. Murtas LNF/INFN
9 July 2002
340
Double Chamber layout
FEE
gas in/outlet
HV
Honeycomb
gas fitting
A
B
gas inlet
gas fitting
gas outlet
G3
G2
G1 F
gas in/outlet
FEE
F. Murtas LNF/INFN
resistors
9 July 2002
GEM FOIL LAYOUT
24 cm
20 cm
F. Murtas LNF/INFN
9 July 2002