The top quark is the heaviest known elementary particle, and its mass is a fundamental parameter of the standard model, one which is important also to determine the phenomenology of new physics models such as Supersymmetric ones. No wonder that since the top quark discovery in 1995 all experiments who have had a chance to measure the top mass have struggled to do so with all available means.

Measuring the top quark entails first of all isolating samples of data containing a sizable fraction of top pair-production events, and then using the measured characteristics of the final state particles emitted in the decay of the quarks to gauge the value of the mass of the two decaying objects.

Two words: production and decay


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