Free neutron structure function at large x Bjorken region

While the structure of the proton has been studied extensively through inelastic electron scattering, much less is known about neutron structure due to the unavailability of high density, free neutrons targets. The BONuS12 experiment was proposed to measure the neutron structure function on a nearly free neutron via the spectator tagging method by tagging the slow backward moving proton. The spectator proton is used to interpret initial momentum of the weakly bound neutron in deuterium atom. A recoil detector will be used to detect spectator protons with momenta $70< P<150 $ MeV/c and the CEBAF Large Acceptance Spectrometer (CLAS12) to detect the scattered electrons. In this talk I will present the design of the recoil detector(RTPC), which was lead by Hampton University, as well as construction and prototyping performed on campus.