Performance of the ESS Target Imaging System under Nominal and Errant Scenarios

• Eric Fackelman (Universitetet i Oslo)

The characteristics of the European Spallation Source proton beam as it approaches the Target are critical to the facility operating at design specifications: producing the brightest neutron source in the world. The European Spallation Source will have one of the highest yet-achieved average power proton beams of 5 million Watts, requiring precise tolerances, efficient cooling, and shielding for everything around the Target due to high radiation levels. The Target Imaging System takes a picture of the beam using light from a luminescent coating on the Target, excited by the protons. This luminescence is a direct measurement of the beam profile. The image processing confirms whether the accelerator and beam shaping devices have produced the correct result. This work estimates the shape of the proton beam at the Target by numerical simulation of the beam as it passes through different parts of the accelerator and uses it for input to the beam profile processing. A scheme for quantifying different parameters of the Target Imaging System beam intensity image is developed and used to define the measurements of a nominal beam. Various simulated beams resulting from hypothetical accelerator malfunctions are compared with the expected beam profile to verify that the Target Imaging System can distinguish between errant and nominal beams.

Ejector-supported Krypton cycle for the future upgrade of the Velo detector

• Luca Contiero

The University of Trondheim (NTNU) and CERN are currently involved in the development and design of a completely new cooling system that will be potentially employed after the upgrade of the LHC (Phase III). The presentation aims to give an insight of the current cooling technologies using CO2 and illustrates the challenges to overcome by going colder in temperatures. An ejector-supported cycle using the noble gas Krypton is here presented, as well as the sketch of the test-rig using Xenon as demonstrator which is currently under construction in Trondheim. To prepare for the test campaign, dynamic modelling of the cycle is still ongoing to set a strategy to entirely fulfill the detector’s requirements such as gradual cooldown and thermal shocks.