Your responsibilities

As an Applied Physicist, you will join the Non-Linear Dynamics and Collimation Section within the Accelerator and Beam Physics Group (ABP) under the Beams Department (BE), where you will work on Collimation and Machine-Detector Interface (MDI) studies contributing directly to the design of the Future Circular Electron Positron Collider (FCC-ee).

The Future Circular Collider (FCC) is meant to be the next generation of higher-performance particle colliders, succeeding the existing Large Hadron Collider (LHC). One of the key challenges for the FCC-ee is that its stored beam energy is about two orders of magnitude higher than in any previous lepton collider, meaning that even minor beam losses could cause substantial damage to accelerator components.

Therefore, beam collimation has unprecedented challenges for this collider. A very-performing system is needed to ensure a reliable operation, acceptable backgrounds for all the experiments, as well as a safe operation in case of unforeseen beam losses.

In this position, you will:

• Help improve the initial design of the FCC-ee collimation system, to ensure the safe disposal of all predicted realistic beam losses and minimise background for experiments.
• Conduct collimation performance and MDI studies for various beam loss processes, as well as iterations on the collimation system design.
• Improve existing simulation codes to assess the collimation performance in lepton machines.
• Collaborate with internal and external teams, providing inputs on beam losses for collimator design and detector background studies.
• Participate in beam measurements in running machines, like Super KEKB in Japan or the LHC, and look for opportunities to apply this knowledge for additional experience and code benchmarking.

Your profile

Skills:

• Basic knowledge of Accelerator Physics;
• Knowledge of simulation tools like X-suite, Mad-X, and/or Geant4 and their coupling to beam dynamics codes would be an asset;
• Familiarity with tools for beam dynamics and particle-matter interaction;
• Knowledge of Programming in Python would be an asset;
• Spoken and written English or French, with a commitment to learn the basics of the other language.

Eligibility criteria:

• You are a national of a CERN Member or Associate Member State.
• You have a professional background in Applied Physics (or a related field) and have either:
• 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.
• You have never had a CERN fellow or graduate contract before.

Additional Information

Job closing date: 30.09.2025 at 23:59 CEST.

Contract duration: 24 months, with a possible extension up to 36 months maximum.

Working hours: 40 hours per week

Target start date: 01-October-2025

Job reference: BE-ABP-NDC-2025-126-GRAP

Field of work: Applied Physics

What we offer

• A monthly stipend ranging between 6287 and 6911 Swiss Francs per month (net of tax).
• Coverage by CERN's comprehensive health scheme (for yourself, your spouse and children), and membership of the CERN Pension Fund.
• Depending on your individual circumstances: installation grant; family, child and infant allowances; payment of travel expenses at the beginning and end of contract.
• 30 days of paid leave per year.
• On-the-job and formal training at CERN as well as in-house language courses for English and/or French.

About us

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. Find out more on http://home.cern.

We are on a Quest. A Journey into discovery like no other. Bring your expertise to our unique work and develop your knowledge and skills at pace. Join world-class subject matter experts on unique projects, in a Quest for greater knowledge and deeper understanding.

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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.