https://doi.org/10.1140/epjc/s10052-017-5162-5
Regular Article - Theoretical Physics
Dissecting multi-photon resonances at the large hadron collider
1
Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA, UK
2
Department of Theoretical Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai, 400 005, India
* e-mail: abhishek@theory.tifr.res.in
Received:
7
July
2017
Accepted:
23
August
2017
Published online:
8
September
2017
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 
s from the n decay are highly collinear and remain unresolved. We discuss how to discriminate this scenario from 
: rather than discarding non-isolated photons, it is better to relax the isolation criteria and instead form photon jets substructure variables. The spins of X and n leave their imprint upon the distribution of pseudo-rapidity gap 
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 decay in this manner. Information on the mass of n can be gained by considering the mass of each photon jet.
© The Author(s), 2017
