The ATLAS High-Luminosity Zero Degree Calorimeter (HL-ZDC) reached an important milestone in the second week of July 2026, with the successful completion of the first HL-ZDC pre-production detector test-beam campaign at CERN’s H4 beam line. After installation on the GOLIATH table, the detector was illuminated with \( e^-, p \) and \(\mu\) beams for the first time and collected about hundreds of millions of events of data needed to characterize its response and validate the detector performance under controlled conditions.
The smooth operation of the detector throughout the campaign and the successful data taking represent an encouraging first step toward the new forward calorimeter for the High-Luminosity LHC for both ATLAS and CMS. The HL-ZDC team will now analyze the collected data in detail and use the results to guide the next stages of the HL-ZDC development. Torino had a strong presence on-site through the whole test beam effort with graduate students Paulina Majchrzak, Phil Stahlhut, and Radek Jirasek, as well as team leader Dr. Riccardo Longo. The ATLAS crew also involved graduate and undergraduate students from Columbia, under the guidance of Prof. Brian Cole, senior scientist and ZDC project leader Dr. Peter Steinberg, and post-docs and graduate students from University of Illinois and BGU.
