1. Status of TRIUMF Prototype Studies Christopher Hearty University of British Columbia/IPP May 31, 2010

2. Drift Tube Study transmission properties of sense wire in a simple system. Jean-Francois has done work using a pulser and scope. Now moving on to using it as a drift chamber. 2

3. 3 2700 mm long 19-mm diameter copper tube strung with 20μm gold-coated tungsten wire (Luma). aluminized-mylar windows

4. Connections 4 1 GHZ bandwidth / 4 GS scope for readout HV

5. Wenteq Amplifier Broadband 10 – 1000 MHz, low-noise, 40 dB gain. But input impedance of 50 Ω is not matched to tube (~420 Ω). 5

6. Gas system Use mass-flow controllers to obtain 80:20 Helium-Isobutane mixture. »maybe try 90:10 as well. Current flow ~100 ml/min. Maybe a bit high for this size of detector. 6

7. Planned measurements Goal is to measure attenuation and dispersion as a function of distance from preamp. Start by looking at 55 Fe signal (~170 e-) at different positions. More challenging: use UV light to generate single electrons from aluminum on windows. 7

8. Large Prototype 44 square cells, 15 mm square, 3 field wires per sense wire, plus surrounding cells for field shaping. 8

9. Drawings Drawings by Robert Henderson are ready, although additional input is welcome. »http://bblab.triumf.ca/~hearty/Super-B- DCH/Prototype/Prototype-1h.dwghttp://bblab.triumf.ca/~hearty/Super-B- DCH/Prototype/Prototype-1h.dwg On hold pending single tube tests. Probably make an extra endplate for Montreal to test service boards. 9

10. 10

11. Service Boards Drawing contains service board concepts, needed to plan mounting and ground points on endplate. Final design by Montreal group. »readout at one end; HV and termination at other. 11

12. Construction Wire, feedthroughs, connectors, copper-clad mylar (outer cylinder), glues all on-hand. Three of four crimpers revived and ready to go. See note by Rocky So: http://bblab.triumf.ca/~hearty/Super-B- DCH/Prototype/PrelimCrimpStudyNote.pdf http://bblab.triumf.ca/~hearty/Super-B- DCH/Prototype/PrelimCrimpStudyNote.pdf 12 120 μm Al wire 182 g operating tension 750 g failure tension

13. Magnet TRIUMF beam line support person is looking for suitable power supply and location for solenoid. Need power, cooling, gas system, DAQ. Maybe M11? 13

14. Wire Aging Tests Test proposed materials using single cell, as per Boyarski. e.g. bare Al wire. 100 mCi 55 Fe source has been ordered; parts are ready. CAMAC DAQ ready + picoammeter. Gas system will need to be more sophisticated than for drift tube tests to get lower flow rates. 14 A. M. Boyarski, Nucl. Instr. Meth. A 535, 632 (2004) size of single electron peak increases due to Malter effect as chamber ages