Optimization of centroid-finding algorithms for cathode strip chambers

We compare the data obtained by a precision cathode strip chamber (CSC) with a static point charge model. The observed strip charge profile is in good agreement with the model prediction. We have used this model to calculate the systematic error of some popular centroid-finding algorithms, and found good agreement with the systematic error observed in the data. We further studied the effect of incidence angle and of anode wire displacements. By using an algorithm based on a hyperbolic secant function (sech 2) to describe the charge profile, we are able to improve the published single layer resolution of our CSC prototype in a muon beam by 14%, from 53.3 ± 0.9 to 45.8 ± 0.7μm.