Mechanical Engineer for the CMS High-Granularity Calorimeter

What you'll do: As a Mechanical Engineer, you will contribute to the development, procurement, assembly, testing and installation of innovative mechanical structures for the High Granularity Calorimeter (HGCAL) of the Compact Muon Solenoid experiment, working with advanced materials and challenging structural and thermal requirements. You will help oversee the surface assembly and testing of the 250-tonne detector, including its CO? cooling, dry gas, cabling and fibre services, as well as its installation and commissioning 100 metres underground. Working in a multinational, multidisciplinary team, you will apply your expertise in structural and thermal calculations, finite element analysis and 3D CAD. Your responsibilities: - Coordinate a team of technicians in assembling and testing the steel structures of HGCAL, comprising more than 200 tonnes of steel plates per endcap. - Provide engineering support for all activities at CERN related to the large-scale active detector components, known as "cassettes" (30-60-degree segments of circular structures with diameters of up to 5 m). This will include the cold testing of "electromagnetic cassettes" and their subsequent stacking with lead plates to form the complete electromagnetic endcaps. - Integrate the hadronic cassettes into the steel structures and provide support for their testing. - Integrate the electromagnetic (30 tonnes) and hadronic (200 tonnes) sections, including their cabling and piping, and support subsequent large-scale testing on the surface. - Help oversee the lowering of the HGCAL endcaps into the CMS cavern and their connection to CMS, including the connection and testing of services. Your profile: - Strong track record in planning and coordinating the handling, assembling and testing of large mechanical structures. - Demonstrated experience in performing thermal and structural calculations of complex mechanical structures using finite element analysis. - Demonstrated experience in developing mechanical assemblies using 3D CAD. - Ability to work successfully and efficiently within multinational, multicultural teams of engineers, scientists and technicians would be an advantage. - Master's Degree or equivalent relevant experience in the field of Mechanical Engineering or a related field. Your skills: - Assembly of mechanical structures and equipment: Knowledge of usual manufacturing methods (milling, turning, etc.), assembly methods (bolted, welding, etc.). - Knowledge and application of mechanical measurement techniques: including quality control methods. - Assembly and integration of detectors: capability to develop and validate manufacturing and installation methods. - Production of 2D drawings and 3D models: proficiency in Catia V5 or equivalent 3D modelling software, good knowledge of drawing annotations. - Knowledge and application of numerical modelling applied to mechanics. - Proficiency in ANSYS would be a strong asset. - Basic understanding of process engineering systems (i.e. cooling plants) would be an asset. - Works well autonomously; takes on activities and tasks without prompting. - Adopts a pragmatic approach; understands the value of adopting generic rather than gold -plated' technical solutions. - Works well in groups and readily fits into a team; participates fully and takes an active role in team activities. - Delivers presentations in a structured and clear way; adjusts style and content to the audience; responds calmly and confidently to questions. - Adapts quickly and resourcefully to shifting priorities and requirements. - Spoken and written English, with a commitment to learn French. Employment conditions: - A valid driving licence. - Work in Radiation Areas. - Interventions in underground installations. - Work during nights, Sundays and official holidays, when required by the needs of the Organization. Ideal start date: 01/01/2027 Contract duration (in months): 48 Grade range: 6 Benchmark job: 200090 - Mechanical Engineer Job flexibility: Fully Onsite For more information about the position and application process, please visit: https://careers.cern/jobs/ep-cms-ec-2026-190-ld/