Abstract
A number of methods have been proposed recently which exploit multiple highly-correlated interpretations of events, or of jets within an event. For example, Qjets reclusters a jet multiple times and telescoping jets uses multiple cone sizes. Previous work has employed these methods in pseudo-experimental analyses and found that, with a simplified statistical treatment, they give sizable improvements over traditional methods. In this paper, the improvement gain from multiple event interpretations is explored with methods much closer to those used in real experiments. To this end, we derive and study a generalized extended maximum likelihood procedure, and find that using multiple jet radii can provide substantial benefit over a single radius in fitting procedures. Another major concern we address is that multiple event interpretations might be exploiting similar information to that already present in the standard kinematic variables. We perform multivariate analyses (boosted decision trees) on a set of standard kinematic variables, a single observable computed with several different cone sizes, and both sets combined. We find that using multiple radii is still helpful even on top of standard kinematic variables (providing a 12% improvement at low p T and 20% at high p T ). These results suggest that including multiple event interpretations in a realistic search for Higgs to \( b\overline{b} \) would give additional sensitivity over traditional approaches.
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ArXiv ePrint: 1407.2892
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Chien, YT., Farhi, D., Krohn, D. et al. Quantifying the power of multiple event interpretations. J. High Energ. Phys. 2014, 140 (2014). https://doi.org/10.1007/JHEP12(2014)140
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DOI: https://doi.org/10.1007/JHEP12(2014)140