Design of the LBNF Beamline

The Long Baseline Neutrino Facility (LBNF) will utilize a beamline located at Fermilab to carry out a compelling research program in neutrino physics. The facility will aim a wide band neutrino beam toward underground detectors placed at the SURF Facility in South Dakota, about 1,300 km away. The main elements of the facility are a primary proton beamline and a neutrino beamline. The primary proton beam (60-120 GeV) will be extracted from the MI-10 section of Fermilab’s Main Injector. Neutrinos are produced after the protons hit a solid target and produce mesons which are subsequently focused by magnetic horns into a 204 m long decay pipe where they decay into muons and neutrinos. The parameters of the facility were determined taking into account the physics goals, spacial and radiological constraints and the experience gained by operating the NuMI facility at Fermilab. The initial proton beam power is expected to be 1.2 MW; however, the facility is designed to be upgradeable to 2.4 MW. We discuss here the design status and the associated challenges as well as plans for improvements before baselining the facility.