Comments on the diphoton excess: critical reappraisal of effective field theory interpretations

  • Jernej F. Kamenik
  • Benjamin R. Safdi
  • Yotam Soreq
  • Jure Zupan
Open Access
Regular Article - Theoretical Physics


We consider the diphoton excess observed by ATLAS and CMS using the most up-to-date data and estimate the preferred enhancement in the production rate between 8 TeV and 13 TeV. Within the framework of effective field theory (EFT), we then show that for both spin-0 and spin-2 Standard Model (SM) gauge-singlet resonances, two of the three processes SZZ, SZγ, and SW W must occur with a non-zero rate. Moreover, we demonstrate that these branching ratios are highly correlated in the EFT. Couplings of S to additional SM states may be constrained and differentiated by comparing the S production rates with and without the vector-boson fusion (VBF) cuts. We find that for a given VBF to inclusive production ratio there is maximum rate of S to gauge bosons, \( b\overline{b} \), and lighter quark anti-quark pairs. Simultaneous measurements of the width and the VBF ratio may be able to point towards the existence of hidden decays.


Beyond Standard Model Effective field theories 


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Copyright information

© The Author(s) 2016

Authors and Affiliations

  • Jernej F. Kamenik
    • 1
    • 2
  • Benjamin R. Safdi
    • 3
  • Yotam Soreq
    • 3
  • Jure Zupan
    • 4
  1. 1.Jozef Stefan InstituteLjubljanaSlovenia
  2. 2.Faculty of Mathematics and PhysicsUniversity of LjubljanaLjubljanaSlovenia
  3. 3.Center for Theoretical Physics, Massachusetts Institute of TechnologyCambridgeU.S.A.
  4. 4.Department of PhysicsUniversity of CincinnatiCincinnatiU.S.A.

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