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arXiv · 1308.0540

Tagging highly boosted top quarks

Sebastian Schaetzel·Michael Spannowsky
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Abstract

For highly energetic top quarks, the products of the decay t->bqq' are collimated. The 3-prong decay structure can no longer be resolved using calorimeter information alone if the particle jet separation approaches the calorimeter granularity. We propose a new method, the HPTTopTagger, that uses tracks of charged particles inside a fat jet to find top quarks with transverse momentum pT >1 TeV. The tracking information is complemented by the calorimeter measurement of the fat jet energy to eliminate the sensitivity to jet-to-jet fluctuations in the charged-to-neutral particle ratio. We show that with the HPTTopTagger, a leptophobic narrow-mass Z' boson of mass 3 TeV could be found using 300/fb of 14 TeV LHC data.

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Sebastian Schaetzel, Michael Spannowsky. 2013-08-02. Tagging highly boosted top quarks. https://doi.org/10.1103/physrevd.89.014007

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