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Measuring Top Quark Polarization in Top Pair plus Missing Energy Events

High Energy Physics - Phenomenology 2013-05-30 v2 High Energy Physics - Experiment

Abstract

The polarization of a top quark can be sensitive to new physics beyond the standard model. Since the charged lepton from top quark decay is maximally correlated with the top quark spin, it is common to measure the polarization from the distribution in the angle between the charged lepton and the top quark directions. We propose a novel method based on the charged lepton energy fraction and illustrate the method with a detailed simulation of top quark pairs produced in supersymmetric top squark pair production. We show that the lepton energy ratio distribution that we define is very sensitive to the top quark polarization but insensitive to the precise measurement of the top quark energy.

Keywords

Cite

@article{arxiv.1207.1101,
  title  = {Measuring Top Quark Polarization in Top Pair plus Missing Energy Events},
  author = {Edmond L. Berger and Qing-Hong Cao and Jiang-Hao Yu and Hao Zhang},
  journal= {arXiv preprint arXiv:1207.1101},
  year   = {2013}
}

Comments

References added. Accepted for publication in Physical Review Letters