Charm Production at HERA
Measurements of open charm production at HERA are reviewed. The paper covers both photoproduction and Deep Inelastic Scattering measurements from the ZEUS and H1 collaborations.
arXiv subjects
Publications and source records attributed to G. P. Heath.
Measurements of open charm production at HERA are reviewed. The paper covers both photoproduction and Deep Inelastic Scattering measurements from the ZEUS and H1 collaborations.
The ZEUS Central Tracking Detector utilizes a time difference measurement to provide a fast determination of the z-coordinate of each hit. The z-by-timing measurement is achieved by using a Time-to-Amplitude Converter which has an intrinsic timing resolution of 36 ps, has pipelined readout, and has a multihit capability of 48 ns. In order to maintain the required sub-nanosecond timing accuracy, the technique incorporates an automated self-calibration system. The readout of the z-by-timing data utilizes a fully customized timing control system which runs synchronously with the HERA beam-crossing clock, and a data acquisition system implemented on a network of Transputers. Three dimensional space-points provided by the z-by-timing system are used as input to all three levels of the ZEUS trigger and for offline track reconstruction. The average z-resolution is determined to be 4.4 cm for multi-track events from positron-proton collisions in the ZEUS detector.