ASTRONOMY, ASTROPARTICLE PHYSICS AND SPACE SCIENCES

European Astronomy, Astroparticle Physics and Space Sciences continue to occupy a world-leading status as a result of a strong portfolio of intergovernmental, multi-national and national Research Infrastructures (RIs) available to the community. The community is strongly organised at the European and national levels, with two bodies dealing respectively with the Astronomy and Astrophysics and the Astroparticle Physics strategy, ASTRONET ASTRONET, a planning and advisory network for European Astronomy
https://www.astronet-eu.org/ and APPEC, APPEC, the Astroparticle Physics European Consortium
https://www.appec.org/ which both started as an ERA-NET and are now self-sustained groups of funding agencies and associated bodies. Their main mission is encouraging a common science vision for all of European Astronomy, delivering a strategic plan and an infrastructure roadmap. In 2023, ASTRONET released The Science Vision and Infrastructure Roadmap 2022-2035. A strategic plan for European Astronomy, Roadmap 2022-2035
https://www.astronet-eu.org/?page_id=521 The APPEC Consortium, which was created in 2012 following the preparatory work of the ASPERA ERA-NET, launched in January 2018 its European Astroparticle Physics Strategy 2017-2026 European Astroparticle Physics Strategy 2017-2026
https://www.appec.org/roadmap and https://www.appec.org/mid-term-review that was updated in September 2023. These European-level community-driven roadmaps, coupled with the planning processes convened by ESO and ESA, have provided strategic coherence and are still being implemented. 

Ground-based telescopes continue to deliver new science. ESO’s Very Large Telescope/Interferometer (VLT/I) is the world-standard, recently contributing to the 2020 Nobel Prize in Physics (research work on the Milky Way supermassive black hole Sgr A*), while the construction of the 39 m diameter Extremely Large Telescope (ESFRI Landmark ELT), is being pursued with first light expected in 2028. The ALMA millimetre/sub millimetre array in the Atacama Desert (Chile), the largest such facility in the world, is in full operation. The international LOw Frequency ARray telescope (LOFAR ERIC) and the Joint Institute for VLBI ERIC (JIVE) in the European Very Long Baseline Interferometry (VLBI) Network, are pathfinders for the ESFRI Landmark SKAO (Square Kilometre Array Observatory) and international infrastructures on their own. High-energy gamma-ray Cherenkov telescopes HESS and MAGIC developed the observation of TeV scale photon sources into a full-fledged Astronomy and are pathfinders for the ESFRI Landmark CTAO (Cherenkov Telescope Array). EGO-Virgo, located near Pisa (Italy), is the present European contribution to the global network for gravitational waves observation, together with LIGO in US and KAGRA in Japan. In this field, the next generation ground-based infrastructure in Europe will be the Einstein Telescope (ESFRI Project ET) while, following the success of the LISA pathfinder ESA mission, the Laser Interferometer Space Antenna (LISA) will be the first space-based gravitational wave observatory. These facilities need to be complemented by a wider network of infrastructures that are aligned to future priorities. 

Over the last decade, extraordinary progress has been achieved across all areas of Astronomy and Space Sciences research, drawing huge interest from the public and media as well as from the wider scientific community. Most Astronomy breakthroughs are actually triggered by technological advancements, improvements in computing methods and capabilities, and new theoretical ideas. This is especially true now, in this era of ‘Big Science, Big Data’.

For example, our recent ability to use gravitational waves and high energy particles to probe the Universe, in combination with the full coverage of the electromagnetic spectrum, is enabling fundamental new discoveries in areas from stellar Physics to Cosmology.

Fundamental questions in today’s Astrophysics are:

• What is the nature of dark matter and dark energy? 
• How to explain cosmic inflation in the very early Universe? 
• Are there deviations from the standard theories and models (general relativity, cosmological model, standard model of Particle Physics)? 
• What are the properties of the first stars, galaxies and black holes in the Universe?
• How do galaxies form and evolve, and how does the Milky Way fit in this context? 
• What are the progenitors of astronomical transients? 
• What physical and chemical processes control stellar evolution at all stages, from formation to death, and how?
• What are the necessary conditions for life to emerge and thrive? Are we alone? 
• How do planets and planetary systems form and evolve? 
• What is the impact of the Sun on the heliosphere and on planetary environments? 
• What are/were the characteristics and habitability of various sites in the solar system, such as Mars or Jupiter’s icy moons? 
• What is the origin of cosmic rays of all energies? 
• How can extreme astrophysical objects and processes probe new fundamental Physics? 

The ESFRI infrastructures cover many of the required capabilities for the desired discoveries. [see Figure 1]

 

 

The ESFRI Landmark ELT (Extremely Large Telescope) is under construction by ESO in Chile with an expected technical ‘first light’ in 2028. This ~€1.5 billion project is funded by the ESO Member States and will deliver the world’s largest ground-based telescope operating in the optical and infrared wavelengths. ESO’s headquarters is in Germany. Most of the construction is led by European commercial contractors, together with significant academic leadership in the design and delivery of its scientific instruments. The ELT remains one of the highest priorities in European and national strategies for Astronomy and will be delivering world-leading science into at least the 2050s. ELT science will benefit considerably from support and integration with facilities focusing on other wavelengths (radio, x-ray, gamma ray, etc.) and in space (JWST, Euclid, etc.).

The ESFRI Landmark SKAO (Square Kilometre Array Observatory) will deliver the worlds’ largest radioastronomy arrays sited in South Africa and Australia later this decade, with a headquarters at Jodrell Bank in the UK. This new intergovernmental organisation has a global partnership which is still growing and includes significant financial and in-kind contributions from partners both within and outside Europe. Like the ELT, construction relies on a mix of commercial contractors and academic groups to deliver the mix of antennae and the computing capability. The total cost of the facility is currently around €2 billion, funded by its Member States. The science from the SKAO will also benefit considerably from integration with other wavelengths (optical, IR, x-ray, etc.) and other radio capabilities (for example the European VLBI network, JIVE ERIC, and LOFAR ERIC that is on-going its LOFAR 2.0 upgrades).

The ESFRI Landmark CTAO (Cherenkov Telescope Array Observatory, soon CTAO ERIC) is commencing construction in the Canary Islands and Chile and is expected to start operation in the next few years. It will observe gamma-rays with energies from a few 10s of GeV to a few 100 TeV for the exploration of the extreme Universe. The project expects to operate as an ERIC and has the support of a broad European partnership but includes some non-European interests. The CTAO is expected to open up new pathways in gamma ray science, with strong links to the programmes of both Astronomy and Astroparticle Physics.

The ESFRI Project EST (European Solar Telescope) is expected to become a world-leading solar physics capability, sited in the Canary Islands. Most of the development work to realise this 4m-diameter, adaptive optics controlled telescope has been completed, in part supported by EC funds. The partnership has recently formed a Canarian Foundation to progress towards an expected ERIC status for the construction phase. Its capabilities will complement those of the US-led DKIST facility in Hawaii and current and proposed space-missions targeting solar physics (Solar Orbiter, Solar-C, etc.).

The ESFRI Project KM3NeT 2.0 (KM3 Neutrino Telescope) underwater facility will hugely advance our understanding of neutrino physics and is currently taking data while completing construction. The large-volume telescope optimised for high-energy neutrino Astronomy (ARCA), and the dedicated detector to resolve the neutrino mass hierarchy (ORCA) have broad community support and are another example of a common interest between Astroparticle Physics and Astronomy.

The confirmation of the existence of gravitational waves and their sustained detection by facilities such as LIGO, EGO-Virgo and KAGRA has opened up this new field of Physics around understanding high energy events. Linked to this is the need for a multi-messenger approach, to combine information from a range of facilities to fully understand the physics behind observed events. The ESFRI Project ET (Einstein Telescope, ESFRI Project since 2021) is expected to be the next-generation European ground-based infrastructure, vital for progress in the observation of gravitational waves. Development and building partnerships are underway, and operation is expected starting by 2040. Gravitational wave science is a further example of a cross-over area with Astroparticle Physics and Particle and Nuclear Physics.

These new facilities under construction are fully aligned and complementary with the major upcoming missions in space (such as the study of dark energy via Euclid, launched in 2023, the study of exoplanets via PLATO and ARIEL, the study of gravitational waves via LISA, space exploration such as the proposed missions to the Moon and Mars). Space-based observatories will require significant investment by European partners to secure leadership in missions led by ESA or in partnership with NASA, JAXA and other international space agencies. Experimental facilities should be complemented by e-infrastructures to cope with the rapidly developing Big Data capabilities of Machine Learning and Artificial Intelligence. Such networks of Research Infrastructures have been established (e.g. Opticon, Radionet, Europlanet) and are an essential part of the European Research Area. There is a long and successful European heritage here, and huge future potential across all areas of Astronomy, to include commercial return, computing and technology, training and outreach. 

The last update of the ASTRONET Science Vision and Infrastructure Roadmap 2022-2035 prioritised facilities currently preparing for construction (CTAO, EST) and the development of a general purpose, wide-field, high multiplex, spectroscopic facility for a telescope of 8-10 metre class. One vision for this is the MSE (MaunaKea Spectroscopic Explorer), though at this time other concepts are being explored, at sites better aligned with European interests. This capability will help capitalise investments in JWST and Euclid in space but also the ELT and US-led, Vera Rubin Observatory (VRO) ground-based facilities. Continued support and development of the 4m-scale wide-field high multiplex spectroscopic facilities, including Weave and 4Most is also essential to ensure critical mass in this new capability.

On the Astroparticle Physics side, the last APPEC strategy 2023 update prioritised the ESFRI infrastructures CTAO, Einstein Telescope and KM3Net together with the Euclid mission, the upgrade of the Auger observatory and the continuation of double-beta decay and dark matter search experiments. APPEC also encourages the development of next-generation experiments to explore the Cosmic Microwave Background (CMB). Current projects with significant European involvement (such as the Simons Observatory in Chile) are seen to be the precursors to the next big facility, CMB-S4, to explore large-scale polarisation in parallel with space-based approaches (such as LiteBIRD, led by Japan but with ESA engagement).

Whilst inclusion within the ESFRI Roadmap is undoubtedly an advantage for many facilities, Astronomy and Space Sciences also require a range of intermediary-scale capabilities to provide test beds, vital follow-up, broad community access (where access to the largest capabilities is sometimes focused upon those who have contributed to their construction or operation, e.g. for SKAO) and training. Laboratory facilities and high performance and high throughput computing are also essential.

 

NUCLEAR AND PARTICLE PHYSICS 

Today’s research in Nuclear and Particle Physics requires infrastructures of a size and cost that can only be built and exploited through international cooperation and cost sharing. The main research directions and programs are designed and developed at the international level with very strong interactions within and among Europe, North America and Japan. But also, China, Korea and Russia are developing new complementary or competing facilities. 

In Particle Physics, the discovery of the Brout-Englert-Higgs (BEH) boson in 2012 has opened a new research field. The BEH mechanism is of central importance to the Standard Model (SM) providing an explanation for the mass of the elementary particles and is at the same time its least understood ingredient. Many of the open questions of Particle Physics are related to this mechanism. The precise measurement of the properties of the BEH boson is of utmost importance to lead the way to a more complete understanding of nature. The exploration of the rich neutrino sector and the search for new particles and interactions, for example those thought to be responsible for dark matter, remains one of the priorities of Particle Physics. Other major areas of activity relate to the intensive and precise determination of the processes already observed, in particular in the ‘electroweak’ and ‘flavour’ sectors, in order to discover any deviations from the predictions of the standard model, which would signal ‘new Physics’.

CERN is the European laboratory for Particle Physics with a recognized worldwide leading role in the field. CERN operates the Large Hadron Collider (LHC) as well as fixed target experiments and installations for developing and testing new detectors and accelerators. The LHC restarted in 2022 for a period of 4 years (Run3) after its second long technical shutdown (LS2) which lasted an additional year due to the COVID crisis. The successful completion of the LHC high-luminosity upgrade (ESFRI Landmark HL-LHC) remains the focal point of European Particle Physics. The installation of the accelerator equipment and the major upgrade of the ATLAS and CMS experiments will take place during the next long technical shutdown (LS3, 2026 to 2028). The HL-LHC will then be in operation until 2041 and will continue to be the reference infrastructure for the discipline worldwide, including for the study of flavour physics (with LHCb) and the quark-gluon plasma (with ALICE). It will increase the amount of data collected tenfold, offering increased sensitivity to the tests of the Standard Model and the possible discovery of new Physics. 

The European Strategy for Particle Physics (ESPP) 
2020 Update of the European Strategy for Particle Physics
https://cds.cern.ch/record/2721370.  was updated in 2020 and recommended an electron-positron Higgs factory as the highest-priority next collider. For the longer term, the European Particle Physics community has the ambition to operate a proton-proton collider at the highest achievable energy. On this basis, a feasibility study for a new flagship accelerator at CERN has been launched and is currently converging towards a new collider (called FCC, Future Circular Collider) located in a 91 km tunnel extending from CERN near Geneva and south towards Annecy in France. Such a machine would, if realised, start out as a Higgs factory (FCC-ee) around 2048. It could later be upgraded in the same tunnel to proton and heavy-ion collisions (FCC-hh) covering the energy frontier from around 2070 until the end of the century. A concrete recommendation on FCC is expected for the next upgrade of the European Strategy for Particle Physics by 2027. In parallel, studies of alternative scenarios based on linear electron-positron colliders (CLIC, ILC) or on the promising but technically highly challenging muon collider continue to be explored. The realisation of at least one of these colliders at CERN is required to secure Europe’s continued leading role in Particle Physics, to elucidate the role of the Higgs boson and the BEH mechanism beyond the capabilities of the HL-LHC, and to continue the exploration of nature at the energy frontier. It should be noted that China is working on a competing program similar to that of the FCC (an electron-positron collider, CEPC, possibly also followed by a proton-proton collider, SPPC). 

In the field of particle accelerators, the challenge is to achieve higher energies and higher intensities that allow access to new or rare physical phenomena, but also improved energy efficiency. Research focuses, in particular, on the improvement of high-current sources and injectors, on the design of high-field superconducting magnets (whose development is crucial for FCC-hh), on the improvement of accelerator gradients (e.g. through better control of the surface states of superconducting radio frequency cavities) and on the development of the ERL (Energy Recovery Linacs) technology. To achieve very high field gradients (> 1 GV/m), new techniques exploiting plasma wakefield acceleration are being explored. The ESFRI Project EuPRAXIA aims at the construction of the worldwide first multi-GeV plasma-based accelerators (laser-driven and beam-driven) with industrial beam quality and user areas. Beam-driven wakefield acceleration is also explored at CERN in the AWAKE project. An Accelerator R&D Roadmap European Strategy for Particle Physics, Accelerator R&D Roadmap
https://arxiv.org/abs/2201.07895 gathering all these topics has been developed and released in 2022 to focus and coordinate the effort at the European level.

Future Particle Physics will require new detector technologies with higher spatial resolution, ultra- precise timing measurements, and more on-detector intelligence. Novel detectors such as quantum sensors will improve the capabilities and open up new opportunities for applications such as medical imaging or photon science. ECFA, the European Committee for Future Accelerators, is an important forum for exchange on these detector technologies developments and has published in 2021 a dedicated R&D Roadmap. The 2021 ECFA detector R&D Roadmap
https://cds.cern.ch/record/2784893 Large-scale data-intensive software and computing infrastructures are also an essential ingredient to the Particle Physics research programme, with major challenges ahead in view of the exploitation of the HL-LHC which will require coordinated R&D efforts. 

After more than six decades of experimental and theoretical studies, neutrinos remain enigmatic particles. Their non-vanishing mass not only challenges the completeness of the Standard Model but also has a measurable effect, due to the relic Big Bang neutrinos, on the evolution of the largest structures of the Universe. Unlike the other fermions, their mass might not be generated through interactions with the Higgs boson. Moreover, neutrinos offer a potential solution to the problem of the lack of antimatter in the universe, and sterile neutrinos are a potential candidate for dark matter. 

The exploration of neutrinos’ fundamental properties requires dedicated infrastructures and experiments, which either produce them using accelerators (long-baseline experiments like T2K and the future Hyper-Kamiokande in Japan, or LBNF-DUNE in the US), nuclear reactors (like JUNO in China), or through their observation from nuclear double-beta decays in underground facilities (e.g. SuperNEMO at the LSM in France, or CUPID at the LNGS in Italy) or as atmospheric and cosmic radiation (like in KM3NeT 2.0, cf. Astrophysics section). Europe’s main strategy in the field is to continue to support long baseline experiments in Japan and the United States. Accelerator-based study of neutrinos is one of the present priorities of the US, See Report of the 2023 Particle Physics Project Prioritization Panel, “Pathways to Innovation and Discovery in Particle Physics” (draft)
https://www.usparticlephysics.org/2023-p5-report/ which is developing the DUNE experiment (based on neutrino beams produced in FNAL, Chicago, and sent to an underground detection facility in a mine in South Dakota) to study the phenomenon of neutrino oscillations. There is a strong collaboration between Europe (including CERN through the Neutrino Platform) and the US around this project, both around the DUNE detectors (e.g. liquid-Ar TPC’s) and on the Fermilab PIP-II accelerator upgrade. 

Searching for dark matter and the exploration of flavour and fundamental symmetries are crucial components of the search for new Physics. This can be done in many ways, for example through precision measurements of flavour physics (like at LHCb at CERN, for which an upgrade is under discussion, or at the Belle-II experiment in Japan, as well as charged-lepton flavour experiments at PSI, FNAL and in Japan), of electric or magnetic dipole moments (e.g. the muon program at PSI), and searches for axions, dark sector candidates and feebly interacting particles. There are striking similarities between the search for neutrinos properties and the search for the nature of dark matter, with theoretical motivations for unresolved questions spanning from Particle Physics through Nuclear Physics. The range of probed masses and possible (very weak) interaction types of cosmic dark matter with ground-based detectors is extremely wide, but some scenarios are being aggressively pursued globally. Chief among them currently is the search for the signature of a massive ≥GeV but weakly interacting particle (WIMP) of cosmic origin, observed directly in large detectors located deeply underground like at the LNGS with the XENON experiment, or indirectly through self-annihilating in cosmic dark matter clusters) or produced directly at colliders such as the LHC. Theorised particles as light as 10¯⁹ eV, such as axions, have however gained attraction over the past decade, requiring very different detection techniques. The identification of the nature of dark matter and getting a better grasp of the physics associated with the neutrino, are major science drivers for the coming decade.

The strategy for the development of Nuclear Physics in Europe is provided by the Nuclear Physics European Collaboration Committee (NuPECC) in its 2017 Long Range Plan (LRP) NuPECC LRP 2017 – Perspectives in Nuclear Physics
https://www.nupecc.org/pub/lrp17/lrp2017.pdf and in the ongoing LRP update to be published in 2024. Nuclear Physics is composed of a broad spectrum of sub-fields including hadron physics, strongly interacting matter at extreme conditions, nuclear structure and reactions, nuclear astrophysics, fundamental interactions and symmetries as well as applications of nuclear science. All these sub-fields extensively exploit several large-scale and more than 15 smaller-scale infrastructures in Europe. The main science drivers are as follows:

• To understand the structure and the origin of the properties of hadrons;
• To pursue the exploration of the nuclear matter phase diagram;
• To explore the limits of stability of nuclear systems and evolution of nuclear structure across the nuclear landscape;
• To understand the origin of elements and how nuclear processes shape the Universe;
• To contribute to the development of new nuclear science technologies for societal applications.

High-energy Nuclear Physics, i.e. relativistic heavy-ion physics at the energy frontier (up to 5 A.TeV centre of mass energy), has progressed towards unprecedented precision understanding of the Quark Gluon Plasma (QGP), based on the dedicated ALICE detector operating at CERN-LHC, but also with significant programs at the other LHC detectors (ATLAS, CMS and recently also LHCb) and at RHIC in the US (sPHENIX and STAR detectors). The ALICE detector has recently (2020-2022) undergone a major upgrade enabling continuous data readout and thus data collection and readout increased by about a factor of 100. An extensive proposal for a new ALICE-3 detector based on large extent on monolithical ultra-thin Si inside a new superconducting magnet (to be eventually deployed around 2034) and a new forward calorimeter (FOCAL) focused on searching for experimental evidence for the Colour Glass Condensate (CGC) from 2029.

At lower beam energies, the ESFRI Landmark FAIR (Facility for Antiproton and Ion Research), in construction in Germany, is developing a dedicated heavy-ion detector (CBM, Compressed Baryonic Matter) targeting the search for the critical point of nuclear matter at energies between 8 and 45 A.GeV, using beams from the future SIS100 synchrotron. 

The diverse field of hadron physics requires a multitude of experimental facilities, either dedicated hadron physics experiments or multi-purpose experiments in neighbouring research fields. The most important from the existing facilities and experiments in Europe are AMBER at CERN, and MESA in Mainz, Germany. The future flagship experiment in Europe is expected to be PANDA at FAIR. The European hadron physics community is also involved in the experimental programs at Jefferson Laboratory in USA, Belle II in Japan, BES III in China as well as in the design and construction of the new EIC (Electron-Ion Collider) project in Brookhaven, USA.

The field of low-energy nuclear physics is undergoing an important transformation based on results obtained at existing facilities such as GANIL in France, GSI-FAIR in Germany, ISOLDE at CERN, JYFL in Finland and LNL & LNS in Italy. These results have motivated very ambitious efforts worldwide to produce and study exotic nuclei using Radioactive Nuclear Beams (RIB). Without forgetting the worldwide RIB facilities in Japan, USA, Canada, China and Korea, the European roadmap is mainly based on FAIR and ESFRI Landmark SPIRAL2. FAIR and GANIL-SPIRAL2 exploit two different and complementary methods to produce radioactive beams. FAIR will deliver high-energy beams of heavy-ions and will have an unrivalled potential to produce exotic nuclei far from stability lighter than uranium (NUclear STructure, Astrophysics and Reactions – NUSTAR programme). GANIL-SPIRAL2 directly produces exotic nuclei, which can then be re-accelerated into high optical quality, high intensity, and lower energy beams for precision measurements as well as very heavy nuclei heavier than uranium. The GANIL-SPIRAL2, ISOLDE and JYFL today, SPES at LNL and ISOL@MYRRHA in the future, will provide precision measurements complementary to those performed with energetic FAIR beams.

While the first experiments with the FAIR detectors available at existing GSI accelerators have been successfully recording data since 2018 as part of the FAIR ‘Phase-0’ program, the actual beginning of operation of the ‘First Science’ phase of the FAIR infrastructure is scheduled for 2028. It will include the start of the NUSTAR and APPA (Atomic, Plasma Physics & Applications) programmes plus possibly the CBM experiment. GANIL, which started the operation of its new superconducting linear accelerator in 2019, will see the full deployment of the phase 1 of its upgrade project, SPIRAL2, by 2030. Phase 1 of SPIRAL2 includes experimental areas with three halls for experiments, respectively with a high flux of fast neutrons (Neutrons for Science, NFS), with very high intensity beams of heavy ions (Super Separator Spectrometer, S3) and with low energy exotic nuclei (DESIR) produced at S3 and with the existing SPIRAL1 facility. While NFS is operational, S3 is scheduled to begin exploitation in 2025. DESIR started its construction in 2023 and the first experiments are planned from 2027. The construction of a new injector for the SPIRAL2 linear accelerator, called NEWGAIN, is planned to extend the range of available high intensity beams to uranium by 2028. 

One of the three pillars of the Extreme Light Infrastructure, See Analytical Physics section. namely ELI-Nuclear Physics (ELI-NP) in Romania, is the most advanced research facility in the field of photonuclear physics, a new interdisciplinary research field which brings together high-power lasers and nuclear physics. The facility includes the highest power (10 PW) operational laser system in the world and begun its broad scientific program in 2020 while continuing the construction of its gamma beam facility.

AGATA (Advanced GAmma Tracking Array) is a new and original mobile RI for nuclear structure Physics and Astrophysics. AGATA is a European collaborative project to build and operate a new type of ultra-pure Germanium gamma ray multi-detector, based on the concept of gamma ray tracking. It reveals the structure of the nucleus under extreme experimental conditions, whether with relativistic beams at FAIR or with the lower energy exotic beams of GANIL and SPES-LNL. AGATA will be used in these European infrastructures, illustrating their complementary nature. 

The range of neutron facilities operating concurrently also supports distinct Nuclear Physics and Astrophysics user groups with their unique needs and objectives. Nuclear Physics research using 'slow' neutrons and the production of radionuclides for research and cancer treatment is concentrated on the ESFRI Landmark ILL (Laue Langevin Institute), a European flagship facility, located in Grenoble. The capacity of high flux neutron time-of-flight measurements will be augmented over the longer term by complementing the present flagship facilities n_TOF at CERN and NFS at GANIL with the new facility, ESFRI Project IFMIF-DONES planned in Spain. In Lund, Sweden, the ESFRI Landmark ESS (European Spallation Source) is being constructed (see section on Analytical Facilities).

The Gran Sasso National Laboratory (LNGS), the largest underground laboratory in the world devoted to neutrino and astroparticle physics, is also of particular importance for nuclear astrophysics. It offers the most advanced underground infrastructure in terms of dimensions, complexity and completeness. For the last 30 years, research in nuclear astrophysics has been carried out by the LUNA Collaboration at LNGS. The collaboration plans to install a new LUNA 400-kV accelerator at LNGS. 

Finally, the European Centre for Theoretical Studies in Nuclear Physics and Related Areas (ECT*) in Trento, Italy, is a globally recognised international research infrastructure in theoretical Nuclear Physics and related areas. Since its inception in 1993, ECT* attracts participants from around the world and is supported by numerous European countries and European framework programs.

For an overview of ESFRI and non-ESFRI RIs in the Particle and Nuclear Physics sub-domain, see Figure 2.

 

 

ANALYTICAL PHYSICS

Analytical Physics (AP) infrastructures (see Figure 3) enable the research on the quantum properties of atomic matter by exploiting the interaction of particle and photon beams with material samples in standard or extreme conditions of pressure, temperature and external fields. By definition, this field is transverse and multidisciplinary; it thus concerns most fields of fundamental or applied scientific research (Materials Science, Biology, Chemistry, Physics, Geology, Health, Heritage Science...). 

Through AP exploitation, key questions like understanding the relationships between the functionality and properties of matter and its atomic structure and dynamics down to attosecond and quantum scale, studying proteins to unravel the complex mechanisms of living organisms or engineering new materials with unprecedented properties can be addressed. The long-term vision shared by the network of AP infrastructures is to contribute to solving the grand societal challenges (digital and green transition, healthy society, climate change…) by exploring frontiers of fundamental and applied scientific research.

A non-exhaustive list of research fields driven by science and applications in the field of Analytical Physics and corresponding examples is:

• Inventing new, more targeted medicines by determining three-dimensional structures of biological molecules;
• Finding effective treatments for cancer based on studies using neutron rich isotopes;
• Creating new functional and optimised materials including topological materials (2016 Nobel prize);
  Novel devices for quantum information processing for future microelectronics;
• Improving energy management and generation through improving fuel cells, batteries and laser fusion processes;
• Contributing to the production of healthier food through detailed understanding of interaction with soils;
• Addressing environment and climate challenges through developing better catalysts for chemical processes and study of aging of building materials;
• Temporal analysis of processes down to the attosecond scale for understanding better enzyme catalysed reactions in cells;
• Preserving cultural heritage by analysing artefacts like historical paintings and scrolls;
• Understanding the physics inside of planets and exploring fundamental symmetries in fundamental Particle Physics.

To maintain the scientific excellence of the AP infrastructures over their wide range of applications, continuous upgrade by developing innovative solutions and pushing the boundaries of the current technologies is mandatory. This is especially true to successfully tackle the challenges of the AP field, that is achieving higher brilliance, higher temporal and spatial resolution, routinely running in situ and in operando experiments and making available the most advanced detector technology. 

 

 

The extremely wide portfolio of matter probes available at the European AP infrastructures, coupled to continuous upgrading plans, represents a formidable asset for the positioning of European research. In order to more efficiently pursue scientifically focused goals by exploitation of the wide range of services available at the AP RIs, the Analytical Research Infrastructures in Europe (ARIE) ARIE consortium
https://arie-eu.org/ consortium has been established, which collects seven European Research Infrastructure (RI) consortia representing about 120 national and international research facilities, including all the thematic ESFRI Projects and Landmarks. The seven networks are: (1) the League for European Accelerator based Photon Sources (LEAPS LEAPS
https://leaps-initiative.eu/), which brings together the European accelerator based light sources; (2) the European Distributed REsearch Infrastructure for Advanced Electron Microscopy (e-DREAM e-DREAM
https://e-dream-eu.org/), which collects the major actors in electron microscopy; (3) LaserLab-Europe, LaserLab
https://www.laserlab-europe.eu/ which coordinates the laser infrastructures; (4) the League of advanced European Neutron Sources (LENS LENS
https://lens-initiative.org/), which includes the neutron facilities; (5) the ESFRI Landmark EMFL, encompassing the high magnetic field facilities; (6) INSPIRE for the proton facilities; and (7) RADIATE for the ion facilities. As a joint effort, the networks thrive to create common tools for data, expand user communities, advance the technologies, and access models including industrial use. 

Photon beams are generated by the globally widest array of electron storage rings and linear accelerator-based free electron lasers. These light sources are gathered at the European level in the LEAPS consortium, which comprises 16 organisations representing 19 light source facilities across Europe. LEAPS has produced strategy roadmaps that encourage the development of new technologies and should keep the European RIs at the highest level of competitiveness. These LEAPS strategic roadmaps are executed as part of a coupled open innovation effort with industry stakeholders who will be able to expand their product portfolios and markets.

The global landscape of synchrotron sources consists of some fifty synchrotron radiation centres worldwide, only three of which being 'high-energy': ESRF (European Synchrotron Radiation Facility, Grenoble, France) at 6 GeV, APS (Argonne, USA) at 7 GeV and SPring8 (Japan) at 8 GeV. In Europe, the user community, estimated to around 30.000 researchers, can access to 12 synchrotrons in operation (including UK and Switzerland), all being national facilities except ESRF which is an international infrastructure gathering 13 member states, broadly acknowledged as the best performing facility. 

High brilliance from the soft to the hard X-rays has expanded the impact of analytical facilities by enabling high resolution, chemical contrast, imaging in domains from the nanostructured materials to the Life Sciences and to the natural and cultural heritage. The major technological evolution of synchrotron light sources today consists in integrating the Multi-Bend Achromats (MBA) technology, initiated at MAX-IV in Sweden, into the storage ring. A reduction of a factor of 10 to 100 in the horizontal emittance of the electron beam is then obtained (down to the diffraction limit), which is accompanied by a gain in the brightness of the light produced by the same factor, as well as an improvement in its coherence. These new performances, in addition to reducing the duration of experiments and therefore increasing access possibilities, open up new fields of application with previously unattainable spatial resolutions and acquisition times, particularly for experiments carried out in situ or in operando. 

ESRF, which was the first 3rd generation synchrotron to arise in 1994, successfully implemented such an upgrade in the recent years (ESFRI Landmark ESRF-EBS, Extremely Brilliant Source, ESFRI Landmark since 2018) has become, since the restart of beam operation in 2020, the first 4th generation high-energy synchrotron. In the near future, all excellent European synchrotron radiation centres will be upgrading their accelerators using this MBA technology. Such upgrade programs are already starting in several of them (e.g. SLS in Switzerland, ELETTRA in Italy, DIAMOND in UK, SOLEIL in France).

Femto-second (fs) time resolution is obtained at advanced academic laser laboratories, offering Research Infrastructure services as well as at dedicated facilities like the free electron lasers (FEL) across the electromagnetic spectrum with Seeded or SASE (Self Amplified Stimulated Emission) amplification mode. FELs offer unprecedented performance for studying the electronic, structural and dynamic properties of matter at the atomic scale, addressing fs dynamics of molecules, proteins, clusters and solids by means of advanced pump-probe scattering and spectroscopy experiments. The ESFRI Landmark European XFEL, inaugurated in September 2017, has 7 instruments in full operation. It is one of the most intense coherent X-ray sources in the world along with the LCLS and forthcoming MHz facilities such as the LCLS II at Stanford (US) and the SHINE at Shanghai (China). The FLASH facility in DESY (Hamburg), which served as a pilot facility for the European XFEL, also provides ultrashort pulses in soft X-rays. All those facilities are based on SASE amplification of radiation pulses and use superconducting accelerator technology. FEL sources based on normal-conducting accelerator technology are also available for European users, such as the Swiss-FEL (SASE) for hard X-rays or the world-unique seeded-source facility FERMI@Elettra operating in the soft-X-rays region. Since 2012, this facility enables ultrafast spectroscopy and imaging experiments for a broad international community.

FEL science will expand in the next decade as the availability of specialised, engineered, light pulses will be exploited in many domains of science, beyond the experimental demonstration phase of recent years. New scientific instrumentation, upgrades and experimental setups will further enable experiments in emerging fields by exploiting non-linear spectroscopy methods and approaching attosecond science. European users will be in an excellent position to exploit FEL sources also thanks to the synergy with advanced laser facilities and their networks as well as with nanoscale-matter characterisation facilities that support the design of ultrafast time domain experiments.

Laser Research Infrastructures in Europe are coordinated through the Laserlab-Europe AISBL network, which comprises 47 leading laser Research Infrastructures in 22 European countries. The majority of the members provide open access to their facilities, through a centralised access-managing system. They enable experiments in a large variety of inter-disciplinary research, covering advanced laser science and applications in most domains of research and technology. The ESFRI Landmark ELI ERIC (Extreme Light Infrastructure) has entered the operation phase. ELI ERIC and ELI-NP Negotiations for the accession of Romania, which is hosting ELI-NP, as member of ELI ERIC are ongoing. are jointly launching users calls since 2022, for the three sites with complementary capabilities: (i) ELI-Beamlines, for new laser-plasma accelerators delivering particles and photon sources at extremely high energies; (ii) ELI-ALPS, for the generation of ultrashort light pulses down to the attosecond time domain with applications in atomic and molecular Physics; (iii) ELI-NP, for nuclear photonics applications with petawatt-class laser systems and a brilliant gamma-ray source. The ELI ERIC infrastructure combines cutting-edge technologies, installation size, and project costs that are unthinkable at the scale of a laboratory. ELI ERIC should then be the gateway to new regimes in fundamental research and foster new laser technologies (technology transfer and innovation). With plasma physics, generation of radiation sources or particle beams and light-matter interaction, the laser facilities make it possible to address major scientific questions in Physics today either in the high-energy-density regime (HDE) or at ultra-high intensities in the relativistic regime (UHI). Recently the European Laser Science and Technology Landscape and Roadmap has been published as a joint report of Laserlab-Europe and ELI.

Neutron radiation is used to study and characterise the properties and behaviour of condensed matter, from the atomic to the macroscopic scale, on time scales ranging from 10-12 to 1 s. Based on the specificities of the neutron-matter interaction (high penetration in matter, magnetic interaction, sensitivity to light atoms in particular to hydrogen and its isotopes, energy and wavelength close to those of the excitations and relaxations encountered in matter...), it is a powerful and unique tool in a wide range of fundamental research fields, in particular in condensed matter and chemistry. The most intense neutron beams are produced either in a nuclear research reactor or by the spallation reaction; the principle of which is based on the interaction of a very high-energy proton beam with a metal target, the neutrons being produced during the decay of the target atoms. Nuclear reactors produce continuous thermalized neutron fluxes (1 meV < E < 150 meV) while spallation sources produce pulsed beams over a very wide energy range, and with high peak intensity (while the time-integrated intensity is generally lower than in a reactor).

Europe has enjoyed a world leading position in neutron radiation, with nearly 6000 regular users of neutron sources in all disciplines, representing more than half of the world’s users. However, since the last decade, the European neutron facilities landscape shows a clear decrease in the overall supply due to the progressive shutdown of nuclear reactors, most of them dating from the 1970s. This will only be partially offset by the ESFRI Landmark European Spallation Source (ESS), currently under construction in Lund (Sweden). ESS is now based on a 2 MW proton accelerator and will install 15 instruments in its initial phase (the original baseline was 5 MW and 22 instruments). It is expected to start up in 2027 and, after some years of ramp-up and possible upgrades, should become the world’s most powerful neutron source. By the end of the 2020s, Europe’s main other neutron sources are expected to be the ESFRI Landmark Laue-Langevin Institute (ILL, Grenoble) and FRM2 (MLZ, Munich) reactors, as well as the ISIS (STFC Rutherford Appleton Laboratory, UK) and the SINQ (Paul Scherrer Institute, Switzerland) spallation sources. The operation of the international ILL facility, whose 58 MW high-flux reactor started up in 1971 and produces the most intense continuous beams of neutrons in the world, is meant to be phased with the ramping-up and full operation of the ESS.

In 2022, the LENS consortium, gathering the ten European-level research facilities in the field, published Neutron Science in Europe, an analysis of the current landscape and future opportunities for neutron facilities. The priority for LENS, in the hypothesis where the ILL reactor stops operation in the 2030s, is therefore to fully develop the full capabilities of the ESS (up to 35 instruments) while ensuring funding for the optimal exploitation of the large national facilities FRM2 (Germany), ISIS (UK) and SINQ (Switzerland), including upgrades (like ISIS II) or extension of their instrument suites. It would be also important to provide an overall joint strategy to match the operation schedule of the ILL with the ramping up to full 5 MW operation of the ESS, and to further develop the new High-Current Accelerator-driven Neutron Source compact concept (HiCANS) which needs a demonstrator soon. An interesting and structuring initiative of LENS is to study the possibilities of optimisation by further integration of their activities in a more formal consortium, ‘European Laboratory for Neutron Scattering’.

In the AP RIs landscape, transmission electron microscopy (TEM) provides advanced characterisation techniques to investigate structural and chemical properties of materials with sub-Angstrom lateral resolution and meV energy resolution, which finds application in a wide range of disciplines from Physics to Materials Technology, Engineering, Chemistry and Life Sciences. Europe’s expertise in electron microscopy is distributed across different scientific sectors, with often regional funding, and a limited international structuring. There are over 100 high-end Electron Microscopy (EM) instruments in Europe with 15 leading laboratories and some SMEs that had formed the networked infrastructure ESTEEM3 to provide access to state-of-the-art TEM instrumentation and methods for industry and academy. The current state of the technique shows rapid technological developments and an increased access demand to advanced TEM instrumentation, beyond what is sustainable at laboratory scale. Also, there is a clear user request for fully interoperable experimental approaches that have the potential to couple correlative, multi-modal and multi-scale experiments with complementary techniques like X-rays, ion beams and optical techniques-based experiments, as is currently explored in the IMPRESS project. Within the ARIE network, the e-DREAM consortium was formed in 2021 to promote cooperation between European advanced electron microscopy laboratories, collaborative research and transnational user programmes. It supports the European electron microscopy and works closely alongside the ESTEEM3 project, the European Microscopy Society, and other RIs like ESFRI Landmark Instruct-ERIC supporting the use of cryo-EM for structural biology applications.

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. Implantation of radioactive ion beams (e.g. at ISOLDE, CERN) into a sample, followed by the detection of the emitted radioactive decay products, provides unique information about the structural and functional properties of the host lattice and form a bridge to Nuclear Physics research.

Infrastructures that develop and operate very high magnetic field facilities are also more and more essential for research in Materials, Engineering and Life Sciences. These distributed infrastructures usually gather diverse analytical scientific instrumentation dedicated to physical measurements under intense fields (like NMR typically), often performed in combination with very low temperatures. The ESFRI Landmark Instruct-ERIC is an emblematic example in the Life Science domain. In the field of extremely high magnetic fields research, activities in Europe are organised under EMFL (European infrastructure European Magnetic Field Laboratory), with a common user access program, outreach, training, and technical developments. The EMFL, based on three laboratories, has the objective of exploring exceptional magnetic fields with, in particular, very high stability and spatial homogeneity. All EMFL facilities have recently been fully renewed or upgraded, are internationally competitive and have complementary specificities.

The optimal usage of the ESFRI and national portfolio of analytical facilities is also crucially supported by distributed resources which provide irradiation facilities, nanoscience laboratories, atomic resolution imaging facilities, high energy and time resolution fine-analysis methods, and advanced computation codes with HPC support. The integrated/distributed AP Research Infrastructures enable European scientists to perform state-of-the-art research directly exploiting the synergy between the large-scale AP RIs and the highly specialised resources from academic research laboratories of national dimension. In the last decade the European Commission has also favoured consolidating distributed infrastructures like NFFA-Europe in the field of nanoscience and nano-microtechnology (a pan-European consortium of 22 international partners) or the RADIATE project (a consortium of 26 ion beam centres). These Research Infrastructures are in the process of evolving towards established legal entities to warrant long-term operation. The European landscape of research in Matter Physics is made unique also by established agreements among the major national Research Performing Organisations to enforce open access for integrated research proposals that merge with the advanced usage of the large radiation sources, to develop complex metadata schemes for expanding the FAIR-data productivity across complementary methods and techniques.