Photoproduction of hidden charm pentaquark states P-c(+)(4380) and P-c(+)(4450)

We propose to study the pentaquark candidates of P-c(+) (4380) and P-c(+) (4450) in J/psi photoproduction and look for further experimental evidence for their nature. Since the photoproduction process does not satisfy the so-called "anomalous triangle singularity" condition their presence in J/psi photoproduction would conclude that they should be genuine states and provide further evidence for their existence.