Design of a Helium Passivation System for the Target Vessel of the Beam Dump Facility at CERN

TL;DR

This paper presents the detailed design and fluid dynamics analysis of a helium passivation system for the target vessel of CERN's Beam Dump Facility, aiming to reduce activation and extend operational life.

Contribution

It introduces a novel helium passivation system design and provides simulation-based validation for its effectiveness in the CERN BDF.

Findings

Fluid dynamics simulations validated helium circulation efficiency.

Detailed design of helium purification and circulation system.

Enhanced safety and longevity of the target vessel environment.

Abstract

The Beam Dump Facility (BDF) is a proposed general-purpose facility at CERN, dedicated to fixed target and beam dump experiments, currently being developed in the context of the Physics Beyond Colliders program. The design of the facility will allow to host different types of experiments, of which SHiP is planned to be the initial one. The core of the facility is a high-density target/dump absorbing the full intensity of the SPS beam and generating a cascade of particles that are detected downstream the target complex. The target and its shielding blocks are positioned inside a vessel, which is planned to be passivized with helium, in order to reduce the activation of the gas surrounding the target and to extend the operational life of materials and equipment. The passivation system that will be in charge of purifying and circulating the helium is a critical component for the operation of the facility. Fluid dynamics simulations have been performed to study the circulation of the helium through the vessel. A detailed design of the helium passivation system and its main components has been developed.