Neutronics Calculations for the Common Shielding Project at ESS

TL;DR

This paper discusses neutronics calculations for the ESS shielding project, focusing on designing cost-effective, standardized shielding solutions for long neutron guides at the European Spallation Source.

Contribution

It introduces a unified approach to neutronics simulations and shielding design for multiple instruments at ESS, optimizing cost and consistency.

Findings

Development of standardized shielding block designs

Implementation of a common neutronics simulation approach

Cost reduction in shielding for long neutron guides

Abstract

The European Spallation Source ESS is being constructed in Lund, Sweden, to be the world's brightest cold pulsed spallation neutron source. The facility uses a 2GeV proton beam hitting a target to produce neutrons. The neutrons are then thermalized in a moderator. Surrounding the moderator are several beam ports connected to neutron guides that transport the cold neutrons. Due to the long-pulse source nature of the ESS, neutron scattering instruments are significantly longer than at most existing facilities, with approximately half the instruments requiring neutron guides that are 150 meters long and only a few shorter than 50 meters. Therefore the shielding cost is dominated by the guide shielding. To fulfill the shielding requirement, a 'Common Shielding Project' has been initiated to deliver cost-effective and standardized solutions for several instruments. This includes both a consistent design of the shielding blocks, as well as a common approach to neutronics simulations.