Study of the Reaction γp→η'ηp

The motivation behind the GlueX experiment is to search for hybrid mesons. There is evidence for an exotic isovector π₁(1600) which has been observed decaying to ηπ and η'π. The π₁(1600) should have an isoscalar partner, the η₁, that can be observed in the η'η system, and a candidate for this state was recently reported by the BESIII collaboration¹. The preliminary analysis presented here considers photoproduction of the final state η'η which decays to 4γπ⁺π^-. The experiment uses a beam of linearly polarized photons with a peak near 9 GeV incident on a hydrogen target that produces these particles. General features of the data including mass spectra and data selection with a focus on removing backgrounds due to photon combinatorics will be shown.

¹M. Ablikim et al.(BESIII Collaboration), Observation of an isoscalar resonance with exotic J^PC=1^-+ quantum numbers in J/ψ→γη'η, [arXiv:2202.00621 [hep-ex]]}