"Our goal is to increase the collision rate by a factor of 10," said Markus Zerlauth, overall project leader for the upgrade, who has worked at CERN for more than 20 years.
The facility will maintain an active analysis program during the shutdown, processing the 332 inverse femtobarns of collision data gathered during Run 3.
"Every transition is always a bit exciting," Zerlauth said.
The newly engineered instrumentation, including an all-silicon tracker and high-granularity timing detectors, will optimize the facility for discovering phenomena outside the Standard Model.
"Then, of course, there is also a bit of wariness, because we see a huge task ahead of us," he added.
Detector Upgrades and Scientific Outlook
The ATLAS collaboration intends to use the multi-year shutdown to fundamentally reinvent its event-selection systems and computing infrastructure.
"The HL-LHC will shape particle physics for decades to come, and preparing for it is among the most ambitious scientific undertakings our collaboration has ever engaged in," said ATLAS Spokesperson Stéphane Willocq.
Physicists plan to leverage the massive existing data pool to execute precision tests on current theories while installation teams rebuild the core systems.
"To record data under these extreme conditions, the ATLAS experiment's core systems have been fundamentally reinvented.
This will allow us to continue pushing the frontiers of knowledge, exploring the limits of our current theories and looking for answers to the questions they leave open," Willocq added.
The global collaboration is mobilizing thousands of members to manage the transition from large-scale components production to underground integration.
