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Tevatron IPM. Proposed design. Overview. Space requirements, location Detector design DAQ system Timing and software Commissioning, calibration and maintenance. Space requirements. Two IPMs can be fitted in about 3.25 m
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Tevatron IPM Proposed design Andreas Jansson - Tevatron IPM review
Overview • Space requirements, location • Detector design • DAQ system • Timing and software • Commissioning, calibration and maintenance Andreas Jansson - Tevatron IPM review
Space requirements • Two IPMs can be fitted in about 3.25 m • Additional space may be required for calibration device (e.g. OTR screen). stand/support Andreas Jansson - Tevatron IPM review
Vacuum system ion pump ion pump variable leak • Incorporate a controllable leak (N2) to increase gas pressure, pumps to localize the ‘pressure bump’ and sector valves for maintenance access. valve ipm ipm sector valve sector valve Andreas Jansson - Tevatron IPM review
Magnet stands • Motorized stands are needed to align detector with the beam (due to large aspect ratio of anode strips). • These can also be used to center the detector on the beam orbit. • Only the vacuum can with detector needs to be moved, the magnets can be fixed. Andreas Jansson - Tevatron IPM review
Location flying wires E0 center • E0 has sufficient free space and is close to flying wires, scrapers, new schottkies etc • Proton/pbar time separation 110-150 ns Andreas Jansson - Tevatron IPM review
Radiation measurements • Radiation levels at 4-5 feet is less than 0.5 rads/hour • With the current 60% duty cycle, that gives an annual dose of 2500 rads (8 years for QIE). Andreas Jansson - Tevatron IPM review
Internal detector design Andreas Jansson - Tevatron IPM review
¼ mm strip spacing. Flex circuit to provide matched transmission line to vacuum interface. 50 pin D-type feedthrus. Shielded twisted pair cable on the outside. Anode board and FE cabling Andreas Jansson - Tevatron IPM review
in tunnel in upstairs PC Pbar revolution marker Proton revolution marker Timing generator Fanout Injection marker Injection event 15 MHz clock (UCD+RFT?) QIE reset PCI BUS? To power supplies Injection mkr QIE reset/reset Proton mkr GPIB (?) controller Pbar mkr 15 MHz Kwame Vince, Mark et al QIE Data Header gen. FPGA • Commands: • Start/stop DAQ • Readout data 16 Anode stirp signals (~128) Fast (wide) memory (8 QIEs) serializer PCI bus DMA xfer Burst mode ~1 Gbit/s optical driver 16 serial links (optical fiber) ~1.6 Gbits/s/link ~23 Gbit/s total QIE Block diagram/data flow chart Andreas Jansson - Tevatron IPM review
Timing 396 ns (21 buckets) p/pbar separation collision injection RF 2/7 ( ) 1/7 Andreas Jansson - Tevatron IPM review
Header timing info • Proton marker bit (marks sample with first proton bunch). • Pbar marker bit (marks sample with first pbar bunch). • Injection marker bit (marks first turn at injection). • QIE mode and cap ID# (4 bits) Andreas Jansson - Tevatron IPM review
Software • Card driver to be provided by CD • Low level code to transfer and sort data. • High level code to analyze (fit) data. • Modify existing IPM LabView program for top level part (at least initially). Need to write new low-level code. Andreas Jansson - Tevatron IPM review
Commissioning • The system timing needs to be adjusted with beam, to compensate for cable delays etc. • Involves adjusting phase of sample clock, plus delays of proton, pbar, and injection marker (to correct for location in ring). • Will be done empirically. Andreas Jansson - Tevatron IPM review
Calibration • A number of cross checks can be performed • Monitor average signal to detect saturation. • Vary B-field to verify electron focusing. • Use internal electron source and/or move detector wrt beam to verify MCP gain uniformity. • Detect parasitic coupling by turning off MCP, clearing voltage etc. Andreas Jansson - Tevatron IPM review
Absolute calibration • In the end, the only way to do an absolute calibration is to compare to another instrument. • Install a simple profile detector next to IPM. • OTR screen would be suitable, and there is interest from the Instrumentation group to build one for the Tevatron. Andreas Jansson - Tevatron IPM review
Maintenance • Monitor MCP gain uniformity and change plates periodically • Monitor QIE cards (current draw) and replace if needed. • Single dead channels is not a disaster, but a dead card may be a problem. • Regular infrastructure (water, magnets, …) Andreas Jansson - Tevatron IPM review
Summary • We believe we have a sound basic design • Need to build and test DAQ system chain (QIE card, buffer card, timing and fanout) • Need to build and test detector unit (including vacuum can) to test RF properties • suppression of parasitic signals • longitudinal impedance. Andreas Jansson - Tevatron IPM review