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Reduction of Statistical Power Per Event Due to Upper Lifetime Cuts in Lifetime Measurements

Jonas Rademacker
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Abstract

A cut on the maximum lifetime in a lifetime fit not only reduces the number of events, but also, in some circumstances dramatically, decreases the statistical significance of each event. The upper impact parameter cut in the hadronic B trigger at CDF, which is due to technical limitations, has the same effect. In this note we describe and quantify the consequences of such a cut on lifetime measurements. We find that even moderate upper lifetime cuts, leaving event numbers nearly unchanged, can dramatically increase the statistical uncertainty of the fit result.

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Jonas Rademacker. 2007-02-09. Reduction of Statistical Power Per Event Due to Upper Lifetime Cuts in Lifetime Measurements. https://doi.org/10.1016/j.nima.2006.09.090

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