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

  • Jernej F. Kamenik
  • Benjamin R. Safdi
  • Yotam SoreqEmail author
  • 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 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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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
    Email author
  • 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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