Mechanical Engineer for CMS Tracker (EP-CMX-ID-2025-158-GRAE)

You will join a dynamic team of engineers, physicists, and technicians dedicated to constructing the CMS Tracker for the High-Luminosity LHC. This state-of-the-art detector will operate at -35°C, utilising a sophisticated CO2-based evaporative cooling system.

During the period covered by this contract, sub-assemblies carrying silicon modules will be received at the Tracker Integration Facility (TIF) on the Meyrin site and integrated into the mechanical structures of the detector. The cooling circuits of the detector will be completed and tested, and large sections of the detector will be operated to validate performance as integration progresses. A large CO2 cooling plant is available at the TIF to support the main integration work, while two smaller plants enable targeted testing of sub-assemblies.

In this role, you will be involved in several key engineering activities related to the tracker construction. Your responsibilities will include:

• Participating in the quality control of the thermal performance of selected structures carrying the silicon modules.
• Contributing to the integration and testing of the on-detector cooling distribution.
• Playing a central role in the operation and maintenance of the cooling plants, while supporting teams from the collaboration involved in detector integration at CERN.

This position offers a unique opportunity to contribute to the assembly and testing of a cutting-edge tracking detector and to take responsibility for the operation of a complex two-phase cooling system.

Your profile

Skills:

• Knowledge of two-phase cooling;
• Quality control;
• Testing of mechanical structures;
• Knowledge of CO2 cooling systems;
• Spoken and written English, with a commitment to learn French.

Eligibility criteria:

• You are a national of a CERN Member or Associate Member State.
• By the application deadline, you have a maximum of two years of professional experience since graduation in Mechanical Engineering (or a related field) and your highest educational qualification is either a Bachelor's or Master's degree.
• You have never had a CERN fellow or graduate contract before.
• Applicants without University degree are not eligible.
• Applicants with a PhD are not eligible.

Job closing date: 22.09.2025 at 23:59 CEST.

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

Target start date: 01-November-2025

This position involves:

• Work in Radiation Areas.
• Interventions in underground installations.
• Residence in the immediate vicinity of the Organisation's installations.
• A valid driving licence.

Job reference: EP-CMX-ID-2025-158-GRAE

Field of work: Mechanical Engineering

What we offer

• A monthly stipend ranging between 5196 and 5716 Swiss Francs (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.

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.