DAQ Card
The data acquisition card (DAQ) is the connective link between the detector and the computer. The electrical input signals are amplified, filtered and sent to the computer.
The DAQ card used in the
students experiments was developed for the Quarknet experiment at FermiLab. There are the following input/output connectors: signal input for up to 4 different photomultiplier detectors, a connector to a GPS receiver board which measures latitude, longitude, atmospheric pressure and temperature, a 5V input to power the DAQ card, an USB connection to the notebook and an output connector for the 5V power supply of the detectors.
To filter the detector signals user defined parameters are used: One parameter is the threshold voltage, which allows to exclude accidental signals caused by electronics noise. The corresponding threshold can be determined by the detector calibration. The other parameter is the
coincidence condition which requires that the signals of different detectors have to appear at the same time. The coincidence condition is used e.g. for the measurement of cosmic particle directions.
Both conditions can be set in the computer program
muonic (manual in German).
If the required conditions are fulfilled, the information of the event is transferred to the computer and visualized in muonic.
Detailed information of the DAQ card is given in the
manual by QuarkNet (in English).