The Compact Muon Solenoid (CMS) experiment’s High-Level Trigger, as deployed during the LHC’s 2009-2026 running period, reconstructs high-energy proton-proton collision events using detector conditions that often lag behind the best available calibrations. Closing that gap by delivering near-real-time, offline-quality calibrations to the online system, also known as “Optimal Calibrations,” is one of the central challenges of High-Luminosity (HL)-LHC operations, and it is the challenge this role will face. This position is part of the Next-Generation Trigger programme.

Your responsibilities

• Work with the CMS Detector Performance Groups (DPGs) and Physics Object Groups (POGs) to develop new and improve calibration algorithms.
• Maintain the successful NGT Demonstrator System, developed during LHC Run 3, ensuring it remains operational and capable of running in replay mode against archived data throughout Long Shutdown 3.
• Building on the NGT Demonstrator System experience, contribute to the design of a realistic, production-grade NGT Data Acquisition and Calibration System implementing the Optimal Calibrations required for CMS's High-Level Trigger during the HL-LHC era. This includes exploring the design space across different compute and storage availability scenarios.
• Integrate and test the production-grade system within the CMS online infrastructure, working closely with system administrators and software engineers to ensure seamless compatibility.
• Conduct thorough testing of the NGT system in a realistic environment, simulating various LHC and CMS operational scenarios to assess performance and reliability.
• Produce detailed reports evaluating the impact of improved online calibrations on the physics performance of the High-Level Trigger.

Be sure to meet the eligibility criteria

• By the application deadline, you have a master’s degree with 2 to 6 years of professional experience since graduation or a PhD with a maximum of 3 years of professional experience since graduation. You are not eligible with only a bachelor’s degree.
• You have never had a CERN fellow or graduate contract before.
• Please pay attention to the additional criteria and requirements for this specific position and mentioned above.