Company Description

At CERN, the European Organization for Nuclear Research, physicists and engineers are probing the fundamental structure of the universe. Using the world's largest and most complex scientific instruments, they study the basic constituents of matter - fundamental particles that are made to collide together at close to the speed of light. The process gives physicists clues about how particles interact, and provides insights into the fundamental laws of nature.

Job Description

Introduction

Are you an Accelerator Physicist or Engineer with expertise in beam dynamics and beam collimation? Do you want to contribute to the optimisation of the CERN accelerator complex—from today’s Large Hadron Collider (LHC) to its High-Luminosity upgrade (HL-LHC) and ambitious future projects? Join a truly international team working at the forefront of science, enabling the delivery of particle beams that power discoveries made by researchers worldwide.

You will join:

• The Accelerators and Beam Physics (ABP) group in CERN’s Beams Department, responsible for beam performance across the entire accelerator chain. The group leads beam dynamics studies on the LHC and its injectors, and R&D for future accelerators such as CLIC, FCC, Muon Collider, and novel acceleration concepts like AWAKE.
• The Non-linear Beam Dynamics and Collimation (NDC) Section develops theoretical, numerical, and experimental studies of beam collimation and linear and non-linear beam dynamics. The section addresses beam loss management, its impact to performance and finding mitigations, e.g. through beam collimation by building predictive models for proton, ion, and lepton beams. These studies are crucial to operate safely and efficiently accelerators at the high-intensity frontier, as well as to optimise background conditions for experiments of present and future colliders.

Looking ahead:

CERN’s top priority, in line with the European Strategy for Particle Physics, is the successful exploitation of the HL-LHC in the 2030s. In parallel, studies are underway for the Future Circular Collider (FCC), exploring proton–proton collisions at ~100 TeV and an electron–positron Higgs and electroweak factory as a possible first stage. Strengthening accelerator R&D, especially in beam dynamics, is central to this long-term vision, and the ABP group is at the heart of these efforts.

Functions

As an Accelerator Physicist, you will participate in the activities related to beam collimation studies and machine-detector interface (MDI) for the CERN accelerators, their upgrades, and future accelerators, through simulations, measurements, and theoretical calculations. You will contribute to the operational performance of the LHC and HL-LHC and join the R&D efforts within the FCC study. You will join the ongoing efforts for accelerator codes development for these studies.

Specifically, you will:

• Develop optics, non-linear beam dynamics and beam collimation concepts in view of evaluating halo generation and loss mechanisms, and perform studies of collimation performance, in particular for optimization of collimation designs and MDI layouts, for CERN present and future synchrotrons and colliders, addressing proton as well as ion operation.
• Study and optimize operational conditions for the HL-LHC collimation system and optimize background induced by beam loss mechanisms, to improve the performance aided by beam measurements and simulations.
• Join the LHC beam commissioning during 2026 and contribute to activities under NDC section responsibility.
• Participate with a key role in the preparation and execution of the startup of these systems in the HL-LHC era starting in 2030; Design and conduct experiments in the existing CERN synchrotrons, and possibly in other operating accelerators to validate the concepts and codes developed.

Qualifications

PhD or equivalent relevant experience in the field of Physics or Engineering or a related field.

Experience:

• Working in a scientific environment, preferably in the design and/or operation of particle accelerators.
• Accelerator physics, with the competence in the field of beam collimation.
• Experimental techniques and analysis of data from beam measurements.
• Development of single-particle beam dynamics simulation codes.

The following experience would be considered an asset:

• Knowledge with one or more of the following codes, in particular for collimation simulations: mAD-X, Xsuite, SixTrack.
• Beam commissioning and performance optimization of existing accelerator facilities.
• Beam Collimation, beam loss mechanisms and experimental background studies.

Technical competencies:

• Knowledge and application of single-particle dynamics (longitudinal/transverse).
• Knowledge and application of beam collimation techniques.
• Analysis and optimization of accelerator performance.
• Simulation, design and development of (part of) particle accelerators.
• Knowledge and application of non-linear beam dynamics.

Behavioural competencies:

• Achieving Results: having a structured and organised approach towards work; being able to set priorities and plan tasks with results in mind.
• Solving Problems: assimilating large quantities of information, identifying key issues and formulating conclusions clearly and concisely.
• Working in Teams: working well in groups and readily fitting into a team; participating fully and taking an active role in team activities.
• Communicating Effectively: expressing opinions, ideas and suggestions with conviction and in a logical/structured manner; keeping to the point.
• Demonstrating Accountability: taking responsibility for own actions and decisions.

Language skills:

Spoken and written English, with a commitment to learn French.

Additional Information

Eligibility and closing date:

Diversity has been an integral part of CERN's mission since its foundation and is an established value of the Organization. Employing a diverse workforce is central to our success. We welcome applications from all Member States and Associate Member States.

This vacancy will be filled as soon as possible, and applications should normally reach us no later than 18.11.2025 at 23:59 CET.

Employment Conditions

Contract type: Limited duration contract (5 years). Subject to certain conditions, holders of limited-duration contracts may apply for an indefinite position.

Working Hours: 40 hours per week

Job Flexibility: Fully Onsite

This position involves:

• Work during nights, Sundays and official holidays, when required by the needs of the Organization.
• Work in radiation-controlled areas

Job grade: 6-7

Job reference: BE-ABP-NDC-2025-214-LD

Field of work: Applied Physics

Benchmark Job Title: Applied Physicist