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STaRBoard. Jamal Rorie 5/09/06 Physics 476. Why do we need ToF info?. Used to determine species of particle Central Drift Chamber records path ToF records time B = 1.5T Apply Lorentz Force Law. Why do we need to upgrade?. Currently Belle has a luminosity of 1.6x10 34 cm -2 /s
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STaRBoard Jamal Rorie 5/09/06 Physics 476
Why do we need ToF info? • Used to determine species of particle • Central Drift Chamber records path • ToF records time • B = 1.5T • Apply Lorentz Force Law
Why do we need to upgrade? • Currently Belle has a luminosity of 1.6x1034 cm-2/s • New technique: crabbing the beam • Belle luminosity will be ~2-3x higher • Background will be ~2-3x higher as well • Old ToF is not fast enough to handle this; a new technique must be tested
Data Collection PMT PMT 1:3 Splitter 1:3 Splitter Leading EdgeLo LevelDiscriminator Leading EdgeHi LevelDiscriminator Leading EdgeHi LevelDiscriminator Leading EdgeLo LevelDiscriminator Mean Timer TDC ADC ADC TDC
Timing SchemeWhat did the PMT know and when did it know it? • Hi level - event trigger • Lo level - higher time resolution
Readout Scheme Event trigger received by STaR Logic request to TDC TDC polls for “hit” around requested time TDC sends data, Logic queries ADC No TDC data,Logic doesn’t query ADC Hit No Hit ADC sends data COPPER I/O carries data downstream
COPPER • COmmon Pipelined Platform for Electronics Readout • One standardized card can control up to 4 boards
STaR Layout HPTDC COPPER 16 HPTDC XC3S2000 CLK LAB3 16 COPPER LAB3
LABRADOR3 • 8 Input Channels
HPTDC • 32 input channels • only 8 used when configured for high precision
Spartan3 • 456 pin pkg(340 used)
ADC Block • ADC • LABRADOR3 • STaR takes in differential signal from upstream • lower noise • modifications necessary • Shaper to elongate signal • Originally 3 GSPS • Now 100-300 MSPS
TDC ECL-to-LVDS HPTDC Logic Spartan3 2000 I/O COPPER TDC, Logic, and I/O Blocks(not quite as exciting)
Shaper Test Elongation good Standard delay confirming Testing
Tasks • Currently • Firmware development • Board population • Ahead • Software development • Firmware testing • Finalization • KEK observations (mid-July)
Online Documentation • http://www.phys.hawaii.edu/~jrorie • Schematics • Updates • Code • Datasheets