Readout and trigger electronics for the TPC vertex chamber

The TPC (Time Projection Chamber)/Two-Gamma facility has been upgraded with a straw vertex chamber for high-luminosity running of the PEP storage ring at the Stanford Linear Accelerator Center. The high-accuracy position resolution of the vertex chamber, measured to within about 4 cm of the beam vertex, will provide an impact parameter resolution of less than 90 mu m for tracks with momenta greater than 1 GeV/c. A description is given of the chamber, preamplifier/discriminator electronics, time-digitizer electronics, TPC triggering, vertex-chamber-trigger electronics, variable-coincidence-width circuitry, and test results.<
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