Calibrating

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In order to count the amount of particles going through a detector in this experiment one must first calibrate the device. A sensor cannot have too little power or it will not detect any particles, but also cannot have too much power or the detector will begin to read the voltage as false counts. There is a specific procedure that must be completed in order to do this correctly. This process is done by systematically increasing the amount of voltage powering each separate detector until a plateau is reached. This plateau is the amount of voltage that is appropriate to take an accurate reading.

While calibrating, two sensors are compared to one another. They are set so that the counter only goes up when there is a coincidence between the two detectors. This process removes any accidental counts given by the power source. This is done by leaving one scintillator is left at a controlled voltage while the other is increased until the coincidence rate begins to rise at an exponential rate. This process is repeated until all four detectors are calibrated.

It is necessary to calibrate and pateau scintillators for nearly every experiment we conducted (a muon lifetime experiment doesn't count coincidences).