1. HBD Gas System and Monitoring Craig Woody BNL HBD Working Group Meeting December 8, 2004

2. C.Woody, HBD Working Group Meeting, 12/8/042 Proposed HBD Gas System CF 4 output gas collected, compressed, purified and reused L.Kotchenda

3. C.Woody, HBD Working Group Meeting, 12/8/043 Gas System Costs Company Name Purchases Cost Dwyer Instruments $3 740.00 Tescom $1 100.00 Ashcroft Aprx.$800.00 ADI $2 000.00 RXI $3 930.00 Omega Engineering, Inc $108.00 Peter Paul Electronics Co $1 094.00 Khan $3 500.00 Miller Energy Inc $5 950.00 Asco $169.00 Swagelok $4 021.10 Newark $810.00 Matheson Aprx.$2 500.00 Hastings Instruments Aprx.$4 800.00 Agilent $1 368.00 National Instruments Aprx.$3 490.00 Total $39 380.1 Two Racks -~$1500 Computer -~$1500 500L buffer cost - $2 500.0 The labor cost is $ 15 000. Total: ~ 60 000.00 (without pipes) L.Kotchenda

4. C.Woody, HBD Working Group Meeting, 12/8/044 Gas Transmission Monitoring  Measure UV transmission of input gas and output gas of each detector half separately  Spread beam and separate into four optical paths  Maximize beam intensity so can (hopefully) use CsI vacuum photodiode (or tetrode, etc..) as readout device(s)  Built mainly from commercial parts Cost ~ $40K D 2 Lamp Monochromator Focusing elements Beam Splitter Input gas Output gas HBD East Output gas HBD West Reference CsI Photodiodes MgF 2 WindowsGas Cells MgF 2 Windows Mirrors Individual Readout D 2 Lamp Monochromator Focusing elements Beam Splitter Input gas Output gas HBD East Output gas HBD West Reference CsI Photodiode MgF 2 Windows Gas Cells MgF 2 Windows Mirrors Shutters Single Readout

5. C.Woody, HBD Working Group Meeting, 12/8/045 CsI QE Monitoring  Install UV lamp(s) inside detector  Run detector in reverse bias mode and measure DC current (special calibration mode)  QE monitoring only done rather infrequently (every few weeks ?)