Search for photoproduction of axionlike particles at GlueX

We present a search for axionlike particles, 𝑎, produced in photon-proton collisions at a center-of-mass energy of approximately 4 GeV, focusing on the scenario where the 𝑎-gluon coupling is dominant. The search uses 𝑎→𝛾⁢𝛾 and 𝑎→𝜋+⁢𝜋−⁢𝜋0 decays, and a data sample corresponding to an integrated luminosity of 168  pb−1 collected with the GlueX detector. The search for 𝑎→𝛾⁢𝛾 decays is performed in the mass range of 180<𝑚𝑎<480  MeV, while the search for 𝑎→𝜋+⁢𝜋−⁢𝜋0 decays explores the 600<𝑚𝑎<720  MeV region. No evidence for a signal is found, and 90% confidence-level exclusion limits are placed on the 𝑎-gluon coupling strength. These constraints are the most stringent to date over much of the mass ranges considered.