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arXiv · 1512.07616

On the 750 GeV di-photon excess

Abstract

We explore several perturbative scenarios in which the di-photon excess at 750 GeV can potentially be explained: a scalar singlet, a two Higgs doublet model (2HDM), a 2HDM with an extra singlet, and the decays of heavier resonances, both vector and scalar. We draw the following conclusions: (i) due to gauge invariance a 750 GeV scalar singlet can accommodate the observed excess more readily than a scalar SU(2)_L doublet; (ii) scalar singlet production via gluon fusion is one option, however, vector boson fusion can also provide a large enough rate, (iii) 2HDMs with an extra singlet and no extra fermions can only give a signal in a severely tuned region of the parameter space; (iv) decays of heavier resonances can give a large enough di-photon signal at 750 GeV, while simultaneously explaining the absence of a signal at 8 TeV.

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BibTeXRIS

Wolfgang Altmannshofer, Jamison Galloway, Stefania Gori, Alexander L. Kagan, Adam Martin, Jure Zupan. 2016-04-27. On the 750 GeV di-photon excess. https://doi.org/10.1103/physrevd.93.095015

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