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arXiv · 1305.3904

Discriminating between lepton number violating scalars using events with four and three charged leptons at the LHC

Francisco del Aguila·Mikael Chala·Arcadi Santamaria·Jose Wudka
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Abstract

Many Standard Model extensions predict doubly-charged scalars; in particular, all models with resonances in charged lepton-pair channels with non-vanishing lepton number; if these are pair produced at the LHC, the observation of their decay into $l^\pm l^\pm W^\mp W^\mp$ will be necessary in order to establish their lepton-number violating character, which is generally not straightforward. Nonetheless, the analysis of events containing four charged leptons (including scalar decays into one or two taus as well as into W bosons) makes it possible to determine whether the doubly-charged excitation belongs to a multiplet with weak isospin T = 0, 1/2, 1, 3/2 or 2 (assuming there are no excitations with charge > 2); though discriminating between the isosinglet and isodoublet cases is possible only if charged-current events cannot produce the doubly-charged isosinglet.

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Francisco del Aguila, Mikael Chala, Arcadi Santamaria, Jose Wudka. 2013-09-10. Discriminating between lepton number violating scalars using events with four and three charged leptons at the LHC. https://doi.org/10.1016/j.physletb.2013.07.014

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