Publicerad: 2025-12-09
Accelerator Engineer (RF Cavity Specialist)
The European Spallation Source (ESS) is one of the largest science and technology infrastructure projects being built today. Our goal is to become the brightest source of neutrons for science and technology and be operational by the end of this decade. A state-of-the-art suite of neutron scattering instruments will be made available to address a wide range of scientific fields in fundamental and materials science. Powered by the world’s most advanced linear proton accelerator, ESS will enable cutting-edge research in materials science, energy, health, and the environment for decades to come.
Join us in shaping the future of science - from the ground up.
About the role:
ESS is at an exciting turning point. It is in transition from being a construction site, to being an operating facility. To help us realise our goal of being the most powerful neutron source in the world, we are now looking for a RF cavity scientist or engineer to join the Linac Group to support the operation, maintenance and development of the normal-conducting and superconducting cavities of the ESS linear accelerator.
In this role, you will be working within a team of technicians and engineers. The ESS linac accelerating elements include an RFQ, 3 buncher cavities, a 5-segment drift-tube linac, 26 double spoke cavities and up to 120 elliptical cavities of two different families (medium beta and high beta). All of the normal conducting front-end, the spokes and 56 elliptical cavities are already installed for the staged commissioning of the facility at 2 MW power. Commissioning with low power beam is under way, and operation with higher beam power is planned to start in 2026 – when the protons can be sent to the spallation target.
Linac group members support operation with 24/7 on-call services and in periods of extended working hours during critical commissioning phases, which may require periods of work during weekends and unsocial hours.
The linac group operates an ion-source test stand (for studies of beam stability/reliability and optimisation) and a Cryomodule test stand. The development of a spare RFQ and of a full cryomodule repair facility are activities that will soon open with the transition to the operation phase. In addition to the operational support, you will have the opportunity to lead activities towards cavity performance recovery strategies (e.g. plasma processing of superconducting RF cavities) and improvements of the handling and testing infrastructure at ESS (e.g. provisions for clean room cavity handling and vertical cavity testing). Your tasks will be managed and coordinated in close collaboration with the other groups of the Accelerator Division, with the Operations Division and in collaboration with ESS in-kind partners. All work at ESS is performed in compliance with rules for health and safety and follows ESS standards for engineering and documentation.
This is a permanent, full-time position based at the ESS Campus in Lund, Sweden.
About you:
To excel in this role, we need a highly skilled and adaptable engineer or scientist with a deep understanding of radio frequency (RF) cavity technology, particle accelerators, and high-power beam physics. You will be responsible for ensuring the reliable operation, maintenance, and development of the normal-conducting and superconducting cavities of the ESS linear accelerator. As such, you should be comfortable working in a dynamic, hands-on, and high-stakes environment where precision, collaboration, and innovation are key to our collective success.
A master’s degree or a PhD in Physics, Engineering, or a related discipline (or equivalent professional experience), as well as extensive technical expertise in superconducting RF cavity systems, accelerator physics, or high-power RF systems is essential for this role. You must have a strong understanding of normal-conducting and superconducting accelerator cavities, including aspects of design, commissioning, and operation.
You need to have extensive, hands-on practical experience with accelerator technology. This includes commissioning, testing, and troubleshooting accelerator components, as well as knowledge of beam dynamics, RF power sources, cryogenic systems, and vacuum technology. You should also be very familiar with beam transport systems, ion sources, and accelerator magnets. Prior experience with low-level RF (LLRF) systems, klystrons, and solid-state RF amplifiers is highly desirable. Experience of ensuring compliance with radiation safety, cryogenic safety, and high-voltage protocols and an ability to assess risks and implement mitigation strategies in an accelerator environment is a prerequisite for this role.
Aside from your technical competence, you should be comfortable working closely with engineers, scientists, technicians, and operations teams. Experience of collaborating with in-kind partners, research institutions, and industrial suppliers would be a benefit. The transition from construction to operation requires flexibility in handling unexpected challenges. Therefore, we need someone who can analyse complex technical issues, identify root causes, and implement effective solutions which balance short-term problem-solving with long-term planning.
Documenting processes, writing technical reports, and presenting findings to colleagues and stakeholders is another important aspect of this role.
Excellent verbal and written English communication skills are required, as this is the working language of ESS.
To apply:
If you see yourself in what we’re looking for, please provide your CV and motivation letter in English by clicking on “apply” and following the instructions. Please be aware that we can only accept direct applications made via the ESS website. Submit your application as soon as you can and quote the job reference number ESD-75716 in your application.
This role requires additional background screening processes and health and safety checks, which will be performed during the recruitment process.
For further information regarding the position, please contact Talent Acquisition Specialist Daniel Nordin Baker on Daniel.Nordin@ess.eu
For trade union information, please contact Unionen representative Nuno Elias on nuno.elias@ess.eu or SACO/Swedish Association of Graduate Engineers representative Marc Kickulies at marc.kickulies@ess.eu
Join us in shaping the future of science - from the ground up.
About the role:
ESS is at an exciting turning point. It is in transition from being a construction site, to being an operating facility. To help us realise our goal of being the most powerful neutron source in the world, we are now looking for a RF cavity scientist or engineer to join the Linac Group to support the operation, maintenance and development of the normal-conducting and superconducting cavities of the ESS linear accelerator.
In this role, you will be working within a team of technicians and engineers. The ESS linac accelerating elements include an RFQ, 3 buncher cavities, a 5-segment drift-tube linac, 26 double spoke cavities and up to 120 elliptical cavities of two different families (medium beta and high beta). All of the normal conducting front-end, the spokes and 56 elliptical cavities are already installed for the staged commissioning of the facility at 2 MW power. Commissioning with low power beam is under way, and operation with higher beam power is planned to start in 2026 – when the protons can be sent to the spallation target.
Linac group members support operation with 24/7 on-call services and in periods of extended working hours during critical commissioning phases, which may require periods of work during weekends and unsocial hours.
The linac group operates an ion-source test stand (for studies of beam stability/reliability and optimisation) and a Cryomodule test stand. The development of a spare RFQ and of a full cryomodule repair facility are activities that will soon open with the transition to the operation phase. In addition to the operational support, you will have the opportunity to lead activities towards cavity performance recovery strategies (e.g. plasma processing of superconducting RF cavities) and improvements of the handling and testing infrastructure at ESS (e.g. provisions for clean room cavity handling and vertical cavity testing). Your tasks will be managed and coordinated in close collaboration with the other groups of the Accelerator Division, with the Operations Division and in collaboration with ESS in-kind partners. All work at ESS is performed in compliance with rules for health and safety and follows ESS standards for engineering and documentation.
This is a permanent, full-time position based at the ESS Campus in Lund, Sweden.
About you:
To excel in this role, we need a highly skilled and adaptable engineer or scientist with a deep understanding of radio frequency (RF) cavity technology, particle accelerators, and high-power beam physics. You will be responsible for ensuring the reliable operation, maintenance, and development of the normal-conducting and superconducting cavities of the ESS linear accelerator. As such, you should be comfortable working in a dynamic, hands-on, and high-stakes environment where precision, collaboration, and innovation are key to our collective success.
A master’s degree or a PhD in Physics, Engineering, or a related discipline (or equivalent professional experience), as well as extensive technical expertise in superconducting RF cavity systems, accelerator physics, or high-power RF systems is essential for this role. You must have a strong understanding of normal-conducting and superconducting accelerator cavities, including aspects of design, commissioning, and operation.
You need to have extensive, hands-on practical experience with accelerator technology. This includes commissioning, testing, and troubleshooting accelerator components, as well as knowledge of beam dynamics, RF power sources, cryogenic systems, and vacuum technology. You should also be very familiar with beam transport systems, ion sources, and accelerator magnets. Prior experience with low-level RF (LLRF) systems, klystrons, and solid-state RF amplifiers is highly desirable. Experience of ensuring compliance with radiation safety, cryogenic safety, and high-voltage protocols and an ability to assess risks and implement mitigation strategies in an accelerator environment is a prerequisite for this role.
Aside from your technical competence, you should be comfortable working closely with engineers, scientists, technicians, and operations teams. Experience of collaborating with in-kind partners, research institutions, and industrial suppliers would be a benefit. The transition from construction to operation requires flexibility in handling unexpected challenges. Therefore, we need someone who can analyse complex technical issues, identify root causes, and implement effective solutions which balance short-term problem-solving with long-term planning.
Documenting processes, writing technical reports, and presenting findings to colleagues and stakeholders is another important aspect of this role.
Excellent verbal and written English communication skills are required, as this is the working language of ESS.
To apply:
If you see yourself in what we’re looking for, please provide your CV and motivation letter in English by clicking on “apply” and following the instructions. Please be aware that we can only accept direct applications made via the ESS website. Submit your application as soon as you can and quote the job reference number ESD-75716 in your application.
This role requires additional background screening processes and health and safety checks, which will be performed during the recruitment process.
For further information regarding the position, please contact Talent Acquisition Specialist Daniel Nordin Baker on Daniel.Nordin@ess.eu
For trade union information, please contact Unionen representative Nuno Elias on nuno.elias@ess.eu or SACO/Swedish Association of Graduate Engineers representative Marc Kickulies at marc.kickulies@ess.eu