Work

Diphoton excess and running couplings

Year: 2016

Type: article

Abstract: The recently observed diphoton excess at the LHC may suggest the existence of a singlet (pseudo-)scalar particle with a mass of 750 GeV which couples to gluons and photons. Assuming that the couplings to gluons and photons originate from loops of fermions and/or scalars charged under the Standard Model gauge groups, we show that there is a model-independent upper bound on the cross section σ(pp→S→γγ) as a function of the cutoff scale Λ and masses of the fermions and scalars in the loop. Such a bound comes from the fact that the contribution of each particle to the diphoton event amplitude is proportional to its contribution to the one-loop β functions of the gauge couplings. We also investigate the perturbativity of running Yukawa couplings in models with fermion loops, and show the upper bounds on σ(pp→S→γγ) for explicit models.

Source: Physics Letters B

DOI: 10.1016/j.physletb.2016.04.031

Authors: Kyu Jung Bae, Motoi Endo, Koichi Hamaguchi, Takeo Moroi

Institutions: The University of Tokyo, Kavli Institute for the Physics and Mathematics of the Universe

Language: English

Topic: Particle physics theoretical and experimental studies

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: diamond

Funders: Ministry of Education, Culture, Sports, Science and Technology, Japan Society for the Promotion of Science

Awards: G3988090857, G3996031655, Dark matter models and their application to cosmology and collider phenomenology, Quarks and Higgs in Supersymmetric Models