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

Front Tracker Geometry x6 18 modules In Italy  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 2 40 modules At UVa GEM module production starting now Total Area ~ 16 m 2 SuperBigbite GEM Trackers

4 GEMs with APV25- front end for card seach of the 8 Polarimeter chambers New design for the SBS GEMmodules for polarimeter trackers by Kondo Gnanvo Need 32 modules + 8 spares

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. Progress so far

5 N 2 HV Test Box Pico-ammeter Storage Shelves Stretching Device Display Monitor Storage Cabinet Ultrasonic bath Our Class 1000 Clean Room (3.5 × 3 m 2 ) Built originally for the BigBite drift chambers construction Located in a large (4.5 m x 9 m) semi-clean area. Additional clean room to be added later this year UVa GEM Lab Mechanical stretching device HV Test N2 Gas box 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

6 N 2 HV Test Box Pico-ammeter Storage Shelves Stretching Device Display Monitor Storage Cabinet Ultrasonic bath Our Class 1000 Clean Room (3.5 × 3 m 2 ) Built originally for the BigBite drift chambers construction UVa GEM Lab Mechanical stretching device HV Test N2 Gas box 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

7 N 2 Box for HV test of GEM Foils Resistors soldered on GEM Assembly Steps of the SBS GEM Prototype at UVa

8

9 Preparation of the readout board Stretching of GEM foils Assembly Steps of the SBS GEM Prototype at UVa

10 Test frames glued

X-axis t1 Y-axis t1 X-axis, t ns Y-axis t ns First results from SBS GEM Prototype: MPD readout

First results from SBS GEM Prototype: SRS readout Distribution of the mean ADC count: Gain uniformity Y-axis (mm) X-axis (mm) X/Y (ADC) = 1.12

First results from SBS GEM Prototype: SRS readout Distribution of the mean ADC count: Gain uniformity Y-axis (mm) X-axis (mm) X/Y (ADC) = 1.12

14

SBS GEM Chamber Gain Calibration

Test pulse = 360 mV, Capacitor = 3.3 pF  Equivalent charges = 7.2 Million e- Injected charges = Equivalent charges / Attenuator  attenuation 3dB to 39 db Pulse generator 360 mV Attenuator 3db to 39 db Capacitor box 3.3 pF GEM chamber readout 50  m APV25 Electronics (MPD and SRS) External trigger Signal form one strip APV 25 Gain Calibration Just did this calibration for both SRS and MPD systems

Pedestal Noise – RMS distribution for 128 stripes ADC chan.

 Module of 50x50cm 2 to replace the 40x50cm 2 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  No protective resistors on the GEM foils  External resistor boards  Gas system same as in Evaristo design New design for the SBS GEM polarimeter trackers –from Kondo Gas inlet Gas outlet window Drift cathode GEM foil 1 GEM foil 2 GEM foil 3

GEM Foil with HV sectors 12 HV sector electrodes Alignment holes gas holes 600 mm 590 mm 562 mm

GEM Frame with outer frame 572 mm 528 mm 572 mm 512 mm 562 mm

GEM Frame without outer frame after assembly 572 mm 512 mm 528 mm

GEM Foil with HV sectors

GEM Foil with HV sectors after assembly 600 mm 528 mm

GEM Foil with HV sectors on its frame after assembly

Readout Support with its outer frame 572 mm 528 mm Up to 660 mm to be decided with Rui 245 mm 10 mm 245 mm 100 mm 562 mm

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

Y-Strips connectors on flexible PCB 80 mm 49.5 mm APV-25 FE cards (Italian Electronics) on scale on the readout board Panasonic connectors X/Y readout board with Panasonic connectors and Italian APV25 based electronics

SBS GEM with APV25 FE cards (Italian Electronics)

Frame Design

4 SBS GEMs with APV25-FE for each of the 8 Polarimeter chambers

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 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. Future plans

Cosmic test results 34