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arXiv · 1205.5267

Enhancing the sensitivity to New Physics in the top-antitop invariant mass distribution

Ezequiel Alvarez
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Abstract

We propose selection cuts on the LHC top-antitop production sample which should enhance the sensitivity to New Physics signals in the study of the top-antitop invariant mass distribution. We show that selecting events in which the top-antitop object has little transverse and large longitudinal momentum enlarges the quark-fusion fraction of the sample and therefore increases its sensitivity to New Physics which couples to quarks and not to gluons. We find that systematic error bars play a fundamental role and assume a simple model for them. We check how a non-visible new particle would become visible after the selection cuts enhance its resonance bump. A final realistic analysis should be done by the experimental groups with a correct evaluation of the systematic error bars.

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Ezequiel Alvarez. 2012-10-04. Enhancing the sensitivity to New Physics in the top-antitop invariant mass distribution. https://doi.org/10.1103/physrevd.86.037501

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