Dissecting Multi-Photon Resonances at the Large Hadron Collider

25 Jul 2018, 18:20
Plaza 1

Plaza 1


Dr Abhishek Iyer (INFN)


We examine the phenomenology of the production, at the 13 TeV Large Hadron
Collider (LHC), of a heavy resonance $X$, which decays via other new on-shell particles $n$ into multi- (i.e.\ three or more) photon final states. In the limit that $n$ has a much smaller mass than $X$, the multi-photon final state may dominantly appear as a two-photon final state because the $\gamma$s from the $n$ decay are highly collinear and remain unresolved. We discuss how to discriminate this scenario from $X \rightarrow \gamma \gamma$: rather than discarding non-isolated photons, it is better instead to relax the isolation criterion and instead form photon jet substructure variables. The spins of $X$ and $n$ leave their imprint upon the distribution of pseudorapidity gap $\Delta \eta$ between the apparent two-photon states. Depending on the total integrated luminosity, this can be used in many cases to claim discrimination between the possible spin choices of $X$ and $n$, although the case where $X$ and $n$ are both scalar particles cannot be discriminated from the direct $X \rightarrow \gamma \gamma$ decay in this manner. Information on the mass of $n$ can be gained by considering the mass of each photon jet.

Parallel Session Alternatives to Supersymmetry

Primary author

Dr Abhishek Iyer (INFN)


Prof. Benjamin Allanach (University of Cambridge (GB)) Disha Bhatia (TIFR)

Presentation materials