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arXiv · 0907.0096

Charge asymmetries of top quarks: a window to new physics at hadron colliders

Paola Ferrario·German Rodrigo
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Abstract

With the next start of LHC, a huge production of top quarks is expected. There are several models that predict the existence of heavy colored resonances decaying to top quarks in the TeV energy range. A peak in the differential cross section could reveal the existence of such a resonance, but this is experimentally challenging, because it requires selecting data samples where top and antitop quarks are highly boosted. Nonetheless, the production of such resonances might generate a sizable charge asymmetry of top versus antitop quarks. We consider a toy model with general flavour independent couplings of the resonance to quarks, of both vector and axial-vector kind. The charge asymmetry turns out to be a more powerful observable to detect new physics than the differential cross section, because its highest statistical significance is achieved with data samples of top-antitop quark pairs of low invariant masses.

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Paola Ferrario, German Rodrigo. 2009-07-01. Charge asymmetries of top quarks: a window to new physics at hadron colliders. https://doi.org/10.1088/1742-6596/171/1/012091

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