High-Level Trigger Calibration Scientist

Job Posting Organization:
CERN, the European Organization for Nuclear Research, is at the forefront of scientific research and technological advancement. Established in 1954, CERN has grown to become one of the world's largest and most respected centers for scientific research, employing over 2,500 staff members and hosting thousands of scientists from around the globe. The organization operates in multiple countries and is known for its collaborative approach, bringing together physicists, engineers, and administrative professionals to push the boundaries of knowledge and innovation. CERN's mission is to explore the fundamental structure of the universe, and it is committed to fostering an inclusive environment where diversity is valued and every contribution is recognized. The organization is dedicated to training the next generation of scientists and engineers, providing opportunities for professional development and growth.

Job Overview:
The High-Level Trigger Calibration Scientist position is a critical role within the Compact Muon Solenoid (CMS) experiment at CERN, specifically focusing on the High-Level Trigger (HLT) system. This position is part of the Next-Generation Trigger programme, which aims to enhance the capabilities of the HLT during the High-Luminosity Large Hadron Collider (HL-LHC) operations from 2009 to 202

• The primary responsibility of this role is to bridge the gap between real-time data processing and offline-quality calibrations, ensuring that the HLT can effectively reconstruct high-energy proton-proton collision events. The successful candidate will work closely with various Detector Performance Groups (DPGs) and Physics Object Groups (POGs) to develop and refine calibration algorithms, maintain the NGT Demonstrator System, and contribute to the design of a production-grade NGT Data Acquisition and Calibration System. This role requires a strong understanding of high-energy physics, programming skills, and the ability to work collaboratively within a team to achieve optimal results.

Duties and Responsibilities:
The duties and responsibilities of the High-Level Trigger Calibration Scientist include:

• Collaborating with CMS Detector Performance Groups (DPGs) and Physics Object Groups (POGs) to develop and enhance calibration algorithms.
• Maintaining the NGT Demonstrator System, ensuring its operational capability and functionality in replay mode against archived data throughout Long Shutdown
• Contributing to the design and implementation of a production-grade NGT Data Acquisition and Calibration System that meets the Optimal Calibration requirements for the CMS High-Level Trigger during the HL-LHC era.
• Exploring various design scenarios based on compute and storage availability to optimize system performance.
• Integrating and testing the production-grade system within the CMS online infrastructure, collaborating with system administrators and software engineers to ensure compatibility.
• Conducting thorough testing of the NGT system in realistic environments, simulating various operational scenarios to evaluate performance and reliability.
• Producing detailed reports that assess the impact of improved online calibrations on the physics performance of the High-Level Trigger.
• Supervising team members and providing guidance and support as needed.

Required Qualifications:
Candidates must possess a professional background in Applied Physics or a related field. The qualifications required for this position include:

• A Master's degree with 2 to 6 years of post-graduation professional experience, or a PhD with no more than 3 years of post-graduation professional experience.
• Experience in the design, development, and validation of calibration workflows for high-energy physics experiments.
• Proficiency in Python and C++ programming languages, as well as familiarity with database management systems.
• Experience with Trigger and Data Acquisition (TDAQ) systems, including hardware and associated tools.
• Practical experience in developing software algorithms within an integrated framework.
• Proficient use of software development tools such as GitHub and GitLab, along with knowledge of continuous integration practices.

Educational Background:
The educational background required for this position includes a Master's degree in Applied Physics or a related field, or a PhD in a relevant discipline. Candidates should have a solid foundation in physics principles and methodologies, as well as experience in high-energy physics research. The educational qualifications should be complemented by practical experience in the field, demonstrating the ability to apply theoretical knowledge to real-world challenges.

Experience:
Candidates should have a minimum of 2 years of professional experience in high-energy physics or a related field if they hold a Master's degree. Those with a PhD should have no more than 3 years of post-graduation experience. Relevant experience should include work in calibration workflows, software development, and familiarity with TDAQ systems. The ideal candidate will have a proven track record of contributing to complex projects and collaborating effectively within a team environment.

Languages:
The mandatory language for this position is English, with proficiency in both spoken and written communication. Candidates are also expected to demonstrate a commitment to learning French, which is considered a valuable asset for working within the CERN community and collaborating with colleagues from diverse backgrounds.

Additional Notes:
This position is offered on a contract basis for a duration of 24 months, with the possibility of extension up to a maximum of 36 months. The working hours are set at 40 hours per week, with hybrid job flexibility. The target start date for this position is January 1, 202

• The role may require work during nights, Sundays, and official holidays, depending on the needs of the organization. The job reference for this position is EP-CMS-TDQ-2026-150-GRAP. The compensation includes a monthly net stipend ranging from 6372 to 7004 Swiss Francs, depending on the candidate's degree, along with 30 days of paid leave per year, comprehensive health insurance coverage, and various allowances based on individual circumstances. Additionally, a relocation package is available, and opportunities for on-the-job training and formal language classes are provided.