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Data Acquisition and Reduction

The data acquisition code used is HIXgif (Heterogeneous Information Exchange). In this system, a front-end 486 PC is interfaced to a CAMAC crate via a HYTEC controller. The PC reads out the data and sends it over the network to a VAX server where the data are stored in a global section. A logger task passes the data to the analyzer which enables the on-line analysis and also write the data to disk and to tape. The data taking is controlled from the PC under MS Windows. Only the events with at least two good X and two good Y chambers are recorded on the tapes. A good chamber is defined as good reading of its TDC's and ADC. The trigger rate is with written to tapes. The filtered event rate is with the CsI modules. During one week of data taking raw events are collected per CsI crystal. The off-line analysis is done by packing the data in PAW Ntples. ADC pedestals, drift time-to-distance lookup tables and the calibration constants are determined for each run.

Bernward Krause
Mon Jan 15 14:57:06 MET 1996