Analytical Physics (AP) Infrastructures explore the frontiers of science ranging from fundamental physics to applied materials science using high-brilliance beams of electrons, neutrons, ions or photons, or high magnetic fields. They offer a variety of analytical techniques based on particle and field interactions with matter. They enable the manipulation and characterization of materials and processes at multiple length scales, from atoms to industrial-scale products and living beings, and in ultrafast timescales down to the attoseconds range. They serve academia, industry and society with strong links to other ESFRI facilities especially in the sectors of energy, environment, health and food. They find use in physics, chemistry, materials science and engineering, environmental research, life sciences, and in the field of cultural heritage.

The AP facilities offer solutions to analyse minute concentrations and chemical speciation of elements in soil, water, plant, animal, and human cells as well as in microbes, allowing the discovery of ways to fight pollution and increase food safety. Micro and nanoscale imaging with different modalities enable the study of cells, their organelles, and their interaction with pharmaceutical products with unprecedented resolution and accuracy. Resolving the structure of proteins and other macromolecules via crystallography has given us the key to understand the biological function of these complex systems. Protein folding dynamics can be revealed by ultrashort X-ray pulses from Free Electron Laser (FEL) sources. CryoEM has emerged as a powerful alternative to crystallography in this field.

The action to reduce greenhouse-gas emissions relies on new technologies and materials, for which the AP RIs offer characterisation in real time and in operando conditions. They work together in the fields of clean energy and climate action to lead the research on rechargeable batteries, fuel cells, hydrogen storage, photovoltaics, catalysis, the circular economy, and other means of cleaner energy production and green industrial processes. They also provide non-destructive analyses of samples for our material cultural heritage and to understand the evolution of life and species on Earth.

High-performances, innovative and stateof-the-art nanotechnologies are also essential to address several of the global challenges identified by Horizon Europe and by the European Green Deal. Nanotechnologies are indeed involved in Clean Energy, Climate Action, Eliminating Pollution but also Cybersecurity or Advanced Biomedical Technologies, Key Digital Technologies and Advanced Computing. Universities and research centers possess top-level skills, with extremely high capabilities in developing new nanotechnologies, facing basic and applied research challenges and serving large communities of users from several different scientific fields. However these skills are often distributed among several tens of centers and their overall performances and capabilities are strongly limited by the lack of structured communication and organization.

The AP scientific case has strong links to other fields of PSE. For astronomy, samples returned from planetary exploration or comet missions are studied using AP facilities, giving crucial information on geology, atmosphere and climate within the planets in our Solar System and beyond, even helping to understand the origin of life. Extreme conditions created by the brightest particle beams ever created by humankind reveal processes and the structure of matter in the interior of giant planets. The AP RIs work strongly together with Particle & Nuclear Physics in research and development of accelerator, beam, laser and detector technologies. The co-operation in technology development, especially in Big Data science, across all fields in PSE, is an increasingly important key to success of the AP RIs.

Current Status

The current status of the ESFRI RIs in the field is given in Table 7.

Major modifications have occurred in the landscape of neutron sources recently. Within Europe, there are now ten such facilities in operation. Two have recently been closed, i.e., the Berlin-based BER-II and the Saclay-based ORPHEE reactors. The start of the ESFRI Landmark European Spallation Source ERIC in Lund (Sweden) is currently foreseen for 2023. ESS will be a gamechanger, far beyond an incremental improvement of the existing sources. It offers up to 100 times the brilliance of current spallation sources, making it the world’s most powerful neutron source. The League of Advanced European Neutron Sources (LENS) brings the European neutron infrastructures together and provides transnational user programs.

Synchrotron light sources and free-electron lasers (FELs) are brought together within the League of European Accelerator-based Photon Sources (LEAPS), a strategic consortium that ensures and promotes the quality and impact of the fundamental, applied and industrial research carried out at these facilities.

There are nearly 15 operating synchrotron light sources in Europe. The advent of Multibend Achromat (MBA) technology has allowed synchrotron storage rings to decrease the horizontal emittance down to the diffraction limit and thus created the 4^th generation of synchrotron light sources. The development started from the MAXIV Laboratory and was followed by the ESFRI Landmark ESRF EBS (Extremely Brilliant Source). There are several plans to upgrade national synchrotrons, e.g. the Diamond Light Source, Petra-III, SOLEIL, and the Swiss Light Source, using different implementations of the MBA technology. This allows the synchrotrons to perform even better for nanoscale materials analysis, operando studies of processes, and enable new uses of coherence properties of the light.

FELs provide ultrashort pulses of very intense highly coherent radiation from a laser-like radiation process with a peak brilliance typically 5-6 orders of magnitude higher than that of a synchrotron light source. These properties make them excellent facilities for studying structural and electron dynamics at the atomic and molecular scale covering the fs-ps time domains. These techniques are often combined with lasers operating at other wavelengths in order to study pump-probe dynamics. There are 9 FEL’s in Europe providing light from the infrared to the hard x-ray range.

Laser RIs and research centres in Europe are coordinated through Laserlab-Europe AISBL. The evolution from a long-standing EU funded network, Laserlab-Europe, to a legal organization maintains a stable and sustainable network of national facilities. This transition strengthens the leading role of Europe in laser research through joint research activities and offers a sustainable centralized access to state-of-the-art laser systems and is open to worldwide collaborations.

The ESFRI Landmark ELI is currently moving from construction to operation of three sites with complementary capabilities: i) ELI-Beamlines, for novel laser-plasma-accelerators delivering particles and photon sources with extremely high energies; ii) ELIALPS, for generation of ultrashort light pulses down to attosecond time domain with applications in atomic and molecular physics; iii) ELI-NP, for nuclear photonics applications with petawatt-class laser systems and a high-energy narrow-bandwidth gamma source. ELI will be the gateway to new regimes in fundamental physics and will promote the advent of new laser technologies.

There are over 100 high-end Electron Microscopy (EM) instruments in Europe with 15 leading laboratories and some SMEs forming a networked infrastructure ESTEEM3ESTEEM3
https://www.esteem3.eu/. It is the primary European portal for EM and provides access to state-of-the-art TEM instrumentation and methodologies for industry and academy. It provides expertise and infrastructure for solving complex problems in physics, materials technology, engineering, and chemistry.

Within the ARIE network, the eDREAM consortium of partners from ESTEEM3 has formed. Both consortia explore possibilities for creating a complementary pan-European Research Infrastructure for advanced EM providing sub-10 meV energy resolution and 50 pm spatial resolution. The recent development of direct electron detectors enabled faster frame rates and higher resolution for physical sciences applications and facilitated the exponential growth of use of cryo-EM for structural biology.

Ion beam analysis techniques provide unique information on the depth-dependent chemical composition, defects and impurities. Ion beams also provide information about the age and origin of geological, archaeological, and cultural heritage samples. Other applications are in the atomic scale modification of materials. A sensitivity enhanced by several orders of magnitude is provided by implantation of radioactive ion beams (e.g., at ISOLDE-CERN) into a sample followed by the detection of the emitted radioactive decay products, providing unique information about the structural and functional properties of the host lattice.

The high magnetic field activities in Europe are organised under the ESFRI Landmark EMFL, with a common user access program, outreach, training, and technical developments. Maximum field strengths are increasing, with two hybrid magnets designed to exceed 43 Tesla (T), and bringing fully superconducting magnets into user operation, non-destructive pulsed magnets up to the vicinity of 100 T at Toulouse and Dresden, while in Toulouse, a semi-destructive pulsed field installation now offers fields of 100-200 T. All EMFL facilities have recently been fully renewed or upgraded, are internationally competitive and have complementary specificities. Two of them (Nijmegen and Dresden) are directly coupled to a THz FEL, allowing unique joint operation.

Gaps, challenges and future needs

The Analytical Physics RIs aim to use the most advanced methods of physics to meet the goals of the five Horizon Europe missions. All AP facilities boost their technologies to increase the beam brilliance or field density to improve the characterisation sensitivity as well as the resolution in time and space.

Short-pulse, high-power lasers and their secondary sources of particles and radiation aim at highly efficient and high repetition rate laser systems to drive laser-plasma based particle accelerators and x-ray sources. Addressing these new needs in laser technology is becoming a challenging task in order to further enlarge the user community in areas with high industrial and societal impact. The laser RIs interact strongly and have a strong impact on Particle & Nuclear Physics through common development of accelerator technologies.

Radically novel electron microscopes aim at three-dimensional imaging of materials’ functional properties. Developments are also needed in sample preparation, in situ microscopy and sub-1-Kelvin microscopies, as well as in low dose imaging of biological and other beam-sensitive materials. Next generation CryoEM, enabled by im - proved technologies for electron beams and detectors, will operate at much lower voltages, making them much more widely available and less damaging to biological samples.

The future unavailability of neutron sources poses a major threat as older sources are closing down while existing sources are unable to cope with the demand and the ESS is still under construction. Therefore, there will be a strong need to continue to support the existing national sources. Several centres are working on the de - velopment of accelerator-based compact neutron sources that can play a strong role in particular applications. Furthermore, the future policies strongly endorse initiatives to seek an optimal way to harmonize neutron and X-ray studies, for example, in the framework of LENS and LEAPS. 

In ion beam facilities, there is a growing interest in the use of radioisotopes in materials research, and institutes like ISOLDE-CERN and GSI are making efforts to accommodate this. Large-scale ion beam infrastructures are complemented by stand-alone ion-beam based techniques like atom probe tomography and helium micros - copy and this synergy will be further pursued.

For high magnetic field facilities coordinated development across RIs (CERN, NS, etc.) is needed to develop even higher static and pulsed magnetic fields and to improve the required materials (superconducting, copper alloys, reinforcement) and enabling a wider portfolio of measurements in the short time scales of pulsed fields.

To fully exploit the potential of nanotechnologies, Europe needs to capitalize on the top-class competences available and investments already made, by streamlining the landscape of upstream research that is currently very fragmented, through a stronger organization. This would enable Europe to build a world-class nanofabrication ecosystem for fundamental research with exceptional performance, able to face the upcoming global challenges.

In conclusion, significant scientific and technological break - throughs are expected from the Analytical Physics infrastructures by exploiting new ways of open cooperation with other fields of PSE and users from different fields of science, new thematic user access modes, as well as the close involvement of industrial research and development.