NLO Corrections to Double Higgs Production in the Higgs Singlet Model

Higgs pair production at the LHC from gluon fusion is small in the Standard Model, but can be enhanced in models where a resonant enhancement is allowed. We examine the effect of a resonant contribution from a second scalar arising in a model with a gauge singlet scalar field in addition to the usual SU(2) scalar doublet, with mass up to $M_H$~600 GeV and discuss the interference effects in double Higgs production. We compute the NLO QCD corrections in the large $m_t$ limit and show that they can significantly distort kinematic distributions near the resonance peak.

Comments: 27 pages, 22 figures. References updated, typos fixed, and discussion added to introduction, Section IVB, and conclusion. Version to appear in PRD

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Affiliations: 1NIKHEF, Amsterdam & Leiden U., 2NIKHEF, Amsterdam, 3NIKHEF, Amsterdam

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