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arXiv · 1512.08378

Broad Diphotons from Narrow States

Haipeng An·Clifford Cheung·Yue Zhang
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Abstract

ATLAS and CMS have each reported a modest diphoton excess consistent with the decay of a broad resonance at ~ 750 GeV. We show how this signal can arise in a weakly coupled theory comprised solely of narrow width particles. In particular, if the decaying particle is produced off-shell, then the associated diphoton resonance will have a broad, adjustable width. We present simplified models which explain the diphoton excess through the three-body decay of a scalar or fermion. Our minimal ultraviolet completion is a weakly coupled and renormalizable theory of a singlet scalar plus a heavy vector-like quark and lepton. The smoking gun of this mechanism is an asymmetric diphoton peak recoiling against missing transverse energy, jets, or leptons.

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Haipeng An, Clifford Cheung, Yue Zhang. 2015-12-28. Broad Diphotons from Narrow States. https://arxiv.org/abs/1512.08378

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