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.
Introduction
The Experimental Physics (EP) Department carries out research in the field of experimental particle physics, supporting several experiments at the Large Hadron Collider (LHC) at CERN. CMS (Compact Muon Solenoid) is a general-purpose particle physics experiment operated by an international collaboration. The physics reach of the CMS experiment is determined by the capability of the trigger and data acquisition (DAQ) system to select and acquire the most interesting events. The EP-CMD group has major responsibilities for developing, operating and upgrading the trigger and DAQ systems. Areas covered include custom electronics, use of advanced networking and processor technologies, distributed systems and software for acquisition, control and monitoring. The group is also responsible for supporting and maintaining the experiment on-line computer farms, networks and mass storage systems.
During the current Run-3 the CMD group is assuring the efficient operation of the DAQ and control systems of the experiment, the operation of the Global Muon Trigger, and the development of a prototype of a novel L1 scouting system. In parallel the group is preparing for the longer-term major Phase-II upgrade of the CMS detector and its trigger and DAQ system, currently foreseen to start operation in 2030. New custom hardware, firmware and software systems are being designed and developed in the DAQ, trigger and scouting domains. The requirements for the Phase-II system are an order of magnitude higher compared to the existing system.
Functions
You will contribute to the development of online software, which controls the custom hardware modules that read out the data from the back-end boards of the CMS sub-detectors. The software will be implemented using an online software framework (XDAQ) which is being modernized for usage in Phase 2. It will run in a distributed system embedded in containers which will be orchestrated with a tool like Kubernetes.
In addition, you will take a leading role in the commissioning of the DAQ custom hardware and software in various test systems and in the final production system. You will be the contact person for sub-systems that need to integrate their back-end readout-electronics into the central DAQ system of the experiment.
In particular, your work will entail:
Play a leading role in designing and implementing the new control software for the custom hardware components, in particular for the part that acquires data from the sub-detectors back-end boards.Develop and maintain a Hardware and Software Kit for sub-detectors to exercise integration with the central DAQ system.Design and operate a “DAQ column” in the CMS integration facility, where sub-detectors can connect their readout systems to a scaled down version of the future Phase-2 DAQ system.Be the contact person of the DAQ group supporting sub-detectors to integrate with the central DAQ system in the CMS integration facility and later at the upgraded CMS experiment.Contribute to an on-call service, organized among all members of the group, to provide support for the CMS DAQ System in the ongoing Run 3.Master's degree or PhD or equivalent relevant experience in the field of operating large DAQ systems and Computer Science or a related field.
Experience:
Experience in development and operation of online-software for data acquisition systems for particle physics experiments.Experience in application development with the C++ and Python programming languages.Experience with containerized applications, their deployment and container orchestration.Experience in the integration of complex electronic systems.Technical competencies:
Knowledge of programming techniques and languages: proven in-depth expertise in C++ and Python.Knowledge and application of software life-cycle tools and procedures: git, GitLab, CI.Development of software for embedded and real-time systems with/without OS.Architecture and Design of control and data acquisition systems, distributed applications, and services.Containerization of software applications.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; producing workable and timely solutions that meet requirements.Working in teams: cooperating constructively with others in the pursuit of team goals; balancing personal goals with team goals; working well in groups and readily fitting into a team; participating fully and taking an active role in team activities.Demonstrating flexibility: adapting quickly and resourcefully to shifting priorities and requirements; actively participating in the implementation of new processes and technologies.Learning and sharing knowledge: keeping up-to-date with developments in own field of expertise and readily absorbing new information; sharing knowledge and expertise freely and willingly with others; coaching others to ensure knowledge transfer.Language skills:
Spoken and written English, with a commitment to learn French.
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 18.06.2025 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
This position involves:
Participation in a regular stand-by duty, including nights, Sundays and official holidays.Interventions in underground installations.A valid driving licence.Work during nights, Sundays and official holidays, when required by the needs of the Organization.Job grade: 6-7
Job reference: EP-CMD-2025-103-LD
Benchmark Job Title: Applied Physicist