Design of the LBNF Beamline Target Station

TL;DR

The paper details the design, challenges, and ongoing R&D of the LBNF Beamline Target Station, aiming to produce an intense neutrino beam for the DUNE experiment with scalable power and optimized components.

Contribution

It presents the current design status and innovative solutions for the LBNF Target Station, including material choices and cooling strategies, to support high-power neutrino beam production.

Findings

Design successfully supports 1.2 MW operation with upgrade potential to 2.4 MW.

Evaluation of alternative shielding gases like nitrogen and helium.

Ongoing R&D focuses on component optimization and safety enhancements.

Abstract

The Long Baseline Neutrino Facility (LBNF) project will build a beamline located at Fermilab to create and aim an intense neutrino beam of appropriate energy range toward the DUNE detectors at the SURF facility in Lead, South Dakota. Neutrino production starts in the Target Station, which consists of a solid target, magnetic focusing horns, and the associated sub-systems and shielding infrastructure. Protons hit the target producing mesons which are then focused by the horns into a helium-filled decay pipe where they decay into muons and neutrinos. The target and horns are encased in actively cooled steel and concrete shielding in a chamber called the target chase. The reference design chase is filled with air, but nitrogen and helium are being evaluated as alternatives. A replaceable beam window separates the decay pipe from the target chase. The facility is designed for initial operation at 1.2 MW, with the ability to upgrade to 2.4 MW, and is taking advantage of the experience gained by operating Fermilab's NuMI facility. We discuss here the design status, associated challenges, and ongoing R&D and physics-driven component optimization of the Target Station.