Design and Construction of a New Irradiation Setup for the 2025 LHC PP Run

The CERN LHC’s High Luminosity (HL) upgrade creates a high radiation environment that will affect, in particular, forward detectors such as the Zero Degree Calorimeter (ZDC) of the ATLAS and CMS experiments. The ZDC is a key component for Heavy Ion (HI) runs and is responsible for the triggering on, and characterization of, the event geometry of HI collisions. In order to construct new, radiation-resistant HL-ZDCs, the radiation tolerance of components of the HL-ZDCs must be irradiated and characterized. The HL-ZDC is a tungsten-fused silica sampling calorimeter, where neutrons are smashed into showers of particles to generate Cherenkov light in fused-silica materials that is then turned into an electrical signal by Photomultiplier tubes (PMTs).

This contribution discusses the plans for installing a new active irradiation holder in the Target Absorbers for Neutrals (TAN) and reading it out using the existing ZDC infrastructure during the 2025 LHC p+p run. This novel device will allow for detailed characterization of the radiation damage of systems composed by different combinations of fused-silica Cherenkov radiators and readout PMTs. The results of this research effort will be crucial to determine the final components of the new HL-ZDCs of ATLAS and CMS.