Mechanical Technician for the CMS ECAL Detector at LHC - European Organization for Nuclear Research (Geneva)

About this position

The summary below is published by European Organization for Nuclear Research on the official vacancy notice. Our own analysis — salary realism, comparable openings, career trajectory, language profile — follows further down the page.

Key responsibilities

According to the vacancy notice, the role centres on the following duties:

• Provide mechanical support for all ECAL activities
• Ensure safe handling of fragile ECAL detector Supermodules during extraction, insertion and refurbishment
• Coordinate logistics of materials and equipment for ECAL detector refurbishment activities
• Serve as technical contact person between CMS experiment site and ECAL refurbishment team
• Provide technical support for detector maintenance activities including cooling systems, mechatronic equipment, and instrumentation set-ups

Are you eligible?

Check these requirements from the notice before investing time in an application:

• Education: Higher Technical Diploma or equivalent relevant experience in Mechanics, Mechatronic or related field
• Experience: Reading 2D/3D designs and manufacturing mechanical parts; design, construction, assembly of mechanical components; detector assembly including cooling, pressure test, leak detection; handling of large and fragile equipment; working with multidisciplinary teams; knowledge of cooling operation and maintenance; experience in logistic coordination
• Languages: English (spoken…), French (commitm…)
• Key skills: Assembly of mechanical structures and equipment, Manufacturing of mechanical parts, Integration of mechanical systems, Operation and maintenance of cooling water systems, Operation of handling system, Achieving Results, Solving Problems, Demonstrating Flexibility, Managing Self, Working in Teams
• Eligibility: Applications welcome from Member States and Associate Member States; valid driving licence required; medical clearance required before contract offer confirmation

Contract and working arrangements

Contract duration: 5 years, with possibility to extend up to 8 years and eligibility for indefinite contract tenure.

Working arrangements: Fully Onsite.

Hiring unit: CMS experiment, ECAL upgrade project.

Position details

Reference

EP-CMS-LD-2026-138-LD

Last Verified

21 July 2026

Position overview

This is the official EU Careers listing for Mechanical Technician for the CMS ECAL Detector at LHC at CERN based in Geneva (Contract Agent). The vacancy reference is EP-CMS-LD-2026-138-LD. The role falls under the Engineering domain.

At [CERN](http://home.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.

Introduction:

As Mechanical Technician you will contribute to the upgrade project of the electromagnetic calorimeter (ECAL) of the CMS detector at LHC covering a large panel of activities and responsibilities, from mechanical works, handling and assembly of detector parts, logistic activities. You will work in close collaboration with all ECAL collaborators and CMS technical team.

Functions:

* Provide mechanical support for all the ECAL activities. * Ensure the safe handling of very fragile ECAL detector Supermodules during extraction, insertion and refurbishment . * Coordinate the logistics of materials and equipment required for ECAL detector refurbishment activities. * Serve as the technical contact person between CMS experiment site and ECAL refurbishment team. * Provide technical support for detector maintenance activities, including cooling systems, mechatronic equipment, and instrumentation set-ups.

* Higher Technical Diploma or equivalent relevant experience in the field of Mechanics, Mechatronic or a related field. * Knowledge of cooling operation and maintenance, experience in logistic coordination.

Experience:

* Reading 2D/3D designs, manufacturing mechanical parts accordingly. * Design, construction, assembly of mechanical components. * Detector assembly (including cooling, pressure test, leak detection). * Handling of large and fragile equipment. * Working with multidisciplinary teams.

The following experience would be an advantage:

* Experience in producing 2D and 3D drawings. * Experience of cutting, polishing and assembly of optical material. * Experience on cabling and soldering. * Knowledge of applying safety regulations and procedures.

Technical competencies:

* Assembly of mechanical structures and equipment. * Manufacturing of mechanical parts. * Integration of mechanical systems. * Operation and maintenance of cooling water systems. * Operation of handling system.

Behavioural competencies:

* Achieving Results: delivering prompt and efficient service taking into account customer needs. * Solving Problems: adopting a pragmatic approach; understanding the value of adopting generic rather than 'gold -plated' technical solutions. * Demonstrating Flexibility: adapting quickly and resourcefully to shifting priorities and requirements. * Managing Self: working well autonomously; taking on activities and tasks without prompting. * Working in Teams: building and maintaining constructive and effective work relationships.

Language skills:

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

Eligibility and closing date:

[Diversity](https://diversity.web.cern.ch/) 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](https://home.cern/about/member-states).

This vacancy will be filled as soon as possible, and applications should normally reach us no later than 21.07.2026 at 23:59 CEST.

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 in Radiation Areas. * Interventions in underground installations. * A valid driving licence. * Work during nights, Sundays and official holidays, when required by the needs of the Organization. * Shift work, when required by the needs of the Organization. * Exposure to lead. * Exposure to risk of falling from heights during scaffolding assembly and dismantling operations. * Exposure to electromagnetic fields under certain exposure conditions. * Given the occupational health risks associated with this position, the selected candidate must obtain medical clearance before a contract offer is confirmed.

Job grade: 3-4

Job reference: EP-CMS-LD-2026-138-LD

Field of work: Mechanical Engineering

Benchmark Job Title: Mechanical Technician

Global Benefits

* A [competitive salary](https://careers.cern/pay-benefits-and-support/)(tax free), increasing in line with your years of relevant experience. * 30 days of paid leave per year plus 2 weeks annual closure. * Coverage by CERN’s comprehensive health insurance scheme (for yourself, your spouse and children), and membership of the CERN Pension Fund. * Family, child and infant monthly allowances depending on your individual circumstances. * A relocation package (installation grant, removal, travel expenses) depending on your individual circumstances. * Possibility to extend your contract up to 8 years + eligibility for indefinite contract tenure.

Overview of CERN -Discover a world where the impossible is made possible!

At CERN, the European Organization for Nuclear Research, we are pushing the frontiers of science and technology. Our groundbreaking work brings together not only physicists but also a diverse range of professionals from engineering, technical, scientific, and administrative fields. Together, we foster an environment where innovation and collaboration thrive.

Every day, we face exciting new challenges and opportunities to contribute to cutting-edge research that shapes our understanding of the universe. We meet these challenges through the diverse perspectives within our teams, ensuring every contribution is valued and driving our shared sense of inclusion and purpose. Diversity is a core value of CERN since its foundation, and it remains central to our mission and continued success.

If you are ready to be part of a dynamic, inclusive community pushing the boundaries of knowledge, CERN is the place where your curiosity and skills can thrive. Be part of our mission to uncover what lies at the heart of the universe!TAKE PART!

More information about us, here:[careers.cern](https://careers.cern/)

Application timeline

This vacancy was first listed on 23 June 2026, 33 days ago.

No closing date is published in the source feed for this position. EU vacancies typically remain open for four to eight weeks; check the official vacancy notice for the cut-off date and time.

Last verified against the EU Careers feed on 21 July 2026 (5 days ago).

Where to learn more

For headcount, mission, and other open vacancies at CERN see the CERN institution page; for the cost of living, correction coefficient, and other postings in Geneva see our Geneva location page; for related vacancies in the Engineering field browse our Engineering domain page.

New to EU careers? Our beginner's guide walks through entry routes, EPSO competitions, and what to prepare. For application logistics see application tips and EPSO competitions.