Transcript UVa GEM Polarimeter Tracker - Jlab Hall-A

Nilanga Liyanage
University of Virginia
UVa GEM Team
Dr. Kondo Gnanvo, Dr. Vladimir Nelyubin, Kiadtisak
Saenboonruang, Chao Gu, Xinzhan Bai , Jie Liu, Seth Schcher,
Taylor Scholz
SuperBigbite GEM Trackers
Front
Tracker
18
modules
Geometry
In Italy
x6



50 cm x 40 cm and 50 cm x 50 cm Modules are
assembled to form larger chambers with different sizes
Front tracker: Six 40 cm x 150 cm GEM layers
 built in Italy – INFN
Polarimeter trackers: Eight 50 cm x 200 cm GEM layers
 to be built in Virginia
GEM module production starting now
Total Area ~ 16 m2
40 modules
At UVa
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New design for the SBS GEMmodules for
polarimeter trackers by Kondo Gnanvo
Need 32 modules + 8 spares
4 GEMs with APV25front end for card
seach of the 8
Polarimeter chambers
Progress so far
• Setup and instrumented the GEM lab
• Constructed two 40 cm x 50 cm prototypes based in the
Rome design
• First chamber under testing now.
• Kondo finalized the new design based on lessons learned.
UVa GEM Lab
•Mechanical stretching device
Our Class 1000 Clean Room (3.5 × 3 m2 )
•HV Test N2 Gas box
Built originally for the BigBite drift chambers construction
•Keithley Picoammeter 6487 with 500
Located in a large (4.5 m x 9 m) semi-clean area.
V source Ohmmeter
Additional clean room to be added later this year
•Ultrasonic bath (Elmasonic S900H )
•APV25 based readout systems with
5000 channels for testing GEMs
•Wiener MPOD High Voltage system
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UVa GEM Lab
•Mechanical stretching device
•HV Test N2 Gas box
Our Class 1000 Clean Room (3.5 × 3 m2 )
Built originally for the BigBite drift chambers construction
•Keithley Picoammeter 6487 with 500
V source Ohmmeter
•Ultrasonic bath (Elmasonic S900H )
•APV25 based readout systems with
5000 channels for testing GEMs
•Wiener MPOD High Voltage system
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Assembly Steps of the SBS GEM Prototype at UVa
Resistors soldered on GEM
N2 Box for HV test of GEM Foils
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Assembly Steps of the SBS GEM Prototype at UVa
Preparation of the readout board
Stretching of GEM foils
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Test frames glued
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First results from SBS GEM Prototype: MPD readout
X-axis
t1
Y-axis
t1
X-axis,
t1 + 25 ns
Y-axis
t1 + 25 ns
First results from SBS GEM Prototype: SRS readout
Y-axis
Distribution of the mean ADC count: Gain
uniformity
X/Y (ADC) = 1.12
X-axis
(mm)
First results from SBS GEM Prototype: SRS readout
Y-axis
Distribution of the mean ADC count: Gain
uniformity
X/Y (ADC) = 1.12
X-axis
(mm)
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SBS GEM Chamber Gain Calibration
APV 25 Gain Calibration
Pulse generator
360 mV
Attenuator
3db to 39 db
Capacitor box
3.3 pF
GEM chamber
readout
50 m
External trigger
APV25 Electronics
(MPD and SRS)
Signal form one strip
• Test pulse = 360 mV, Capacitor = 3.3 pF  Equivalent charges = 7.2 Million e-
• Injected charges = Equivalent charges / Attenuator  attenuation 3dB to 39 db
Just did this calibration for both SRS and
MPD systems
Pedestal Noise – RMS distribution for 128 stripes
ADC
chan.
New design for the SBS GEM polarimeter trackers –from Kondo

Module of 50x50cm2 to replace the
40x50cm2
• 32 modules to be built instead of 40 for
the 8 Polarimeter chambers

Wider GEM frames along x-axis
• Width of 30 mm instead of 8 mm
• Better stretching
• alignment holes away from active area

Wider readout support frame along x-axis
(74 mm)
• Room for strips connectors and GEM
HV sectors electrodes
Gas outlet
Gas inlet
window

No protective resistors on the GEM foils
 External resistor boards
Drift cathode
GEM foil 1
GEM foil 2

GEM foil 3
Gas system same as in Evaristo design
GEM Foil with HV sectors
gas holes
562 mm
600 mm
590 mm
562 mm
12 HV sector
electrodes
Alignment holes
GEM Frame with outer frame
572 mm
572 mm
512 mm
562 mm
528 mm
512 mm
562 mm
528 mm
512 mm
GEM Frame without outer frame after assembly
512 mm
572 mm
GEM Foil with HV sectors
GEM Foil with HV sectors after assembly
528 mm
600 mm
GEM Foil with HV sectors on its frame after assembly
Readout Support with its outer frame
100 mm
245 mm
10 mm
562 mm
100 mm
245 mm
10 mm
572 mm
562 mm
528 mm
Up to 660 mm to be decided with Rui
Readout Support with its outer frame
Keeping the outer frame during assembly
Fixation holes
Alignment holes
Readout support after assembly
528 mm
Up to 660 mm to be decided with Rui
X/Y readout board with Panasonic connectors and Italian APV25 based electronics
Y-Strips connectors on
flexible PCB
49.5 mm
80 mm
Y-Strips connectors on
flexible PCB
APV-25 FE cards (Italian
Electronics) on scale on the
readout board Panasonic
connectors
SBS GEM with APV25 FE cards (Italian Electronics)
Frame Design
4 SBS GEMs with APV25-FE for
each of the 8 Polarimeter chambers
Future plans
• Install new clean room and upgrade equipment.
• Parts for two 50 cm x 50 cm prototypes ordered – expect
delivery by December.
• Complete the construction of prototypes by February.
• March to May 2013.
• Characterize the chambers, finalize the design and order
parts for 8 (?) chambers.
•Order Electronics for 8 chambers
• Proposed production schedule
• May 2013 – May 2014 – 8 modules
• May 2014 – May 2015 – 16 modules
• May 2015 – May 2016 – 16 modules
It is crucial that we get our GEM foil orders out as soon possible.
Cosmic test results
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