The European Spallation Source (ESS) [1], located in Lund, Sweden, is nearing completion and represents a significant advancement in neutron science research. Designed to be the world's most powerful neutron source, the ESS has achieved several significant milestones in its construction. The high-energy proton linac, responsible for driving the spallation process, has been successfully tested, and critical components such as the neutron target station and instrument infrastructure are now close to hot commissioning. The facility’s technical complexity and scale, incorporating cutting-edge technologies in accelerator physics, neutron optics, and detection systems, reflect its ambition to transform the way neutrons are harnessed for scientific exploration. As construction progresses, ESS has transitioned into a new operational phase, focusing on the commissioning of its first suite of instruments and preparing them for experimental research and the users. An update on the status and the near prospects will be presented.
The "first science" opportunities at the ESS will validate the performance of the initial instruments, including LOKI, ODIN, DREAM, and others, marking the beginning of scientific operations and the user program. Each of these instruments is tailored to address specific scientific challenges. For instance, LOKI, a small-angle neutron scattering instrument, will provide insights into nanoscale structures and dynamics, enabling research into soft matter, polymers, and biological systems. ODIN is designed to perform high-resolution neutron imaging, making it ideal for investigating structural properties in engineering materials and complex natural systems. DREAM leverages neutron diffraction techniques to study atomic arrangements and phase transitions in materials critical to energy and quantum technologies. By conducting the first experiments, the ESS will establish baseline operations for its instruments and demonstrate the unprecedented capacity of its neutron beamlines. Here, it is equally important to underline the contributions of early users and the broader user communities, whose expertise, feedback, and collaborative research will be vital to refining the ESS’s capabilities and ensuring its impact on scientific advancement across various fields. The way to get involved will be depicted.