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arXiv · 1305.1878

Analytic solutions for neutrino momenta in decay of top quarks

Burton A. Betchart·Regina Demina·Amnon Harel
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Abstract

We employ a geometric approach to analytically solving equations of constraint on the decay of top quarks involving leptons. The neutrino momentum is found as a function of the 4-vectors of the associated bottom quark and charged lepton, the masses of the top quark and W boson, and a single parameter, which constrains it to an ellipse. We show how the measured imbalance of momenta in the event reduces the solutions for neutrino momenta to a discrete set, in the cases of one or two top quarks decaying to leptons. The algorithms can be implemented concisely with common linear algebra routines.

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Burton A. Betchart, Regina Demina, Amnon Harel. 2013-10-02. Analytic solutions for neutrino momenta in decay of top quarks. https://doi.org/10.1016/j.nima.2013.10.039

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