Study of LHCb pentaquarks with CLAS12

The experimental study of the $J/\psi$ photoproduction near threshold is an attractive subject for studying the nucleon gluonic form-factor and, as has been shown recently, is a direct way to produce and study hidden-charm pentaquark states claimed by the LHCb, $P_{c}(4380)$ and $P_{c}(4450)$. The CLAS12 experiment in Hall B at Jefferson Laboratory has developed a program to measure near-threshold $J/\psi$ photoproduction using the low-$Q^2$ electroproduction technique. Given the foreseen resolution in the invariant mass of the $p-J/\psi$ system and the expected production rate for the pentaquark states, the experiment will be able to unambiguously confirm the existence of these states, measure the corresponding line-shape, and determine their quantum numbers.