Gravitational-wave (GW) Astronomy opened a new window to the Universe from its infant state to the present. The key physical systems which allow probing the Universe through these vast time and length scales are Black Holes (BH). Low metallicity clouds, composed primarily… Read more of atomic hydrogen, before and during the epoch of reionization, are a natural environment for BHs to be born and form Binary Black Holes (BBH) which can merge via GW emission. Stellar BHs, being the remnants of the death of very massive stars, are generated early when a huge gas reservoir is available for accretion. Mass segregation leads the BHs close to the center of the system and a dense BH-subcluster, supported by gravitational fluctuations, is formed. The low metallicity of the gas suppresses cooling, while turbulence of the gas and the BHs’ motion further favor quasi-spherical accretion, surpassing the Eddington limit. For sufficiently compact configurations, the BHs shall grow in mass before the gas is depleted by stellar evolution and formation feedback processes. This rapid mass growth through turbulent hot accretion shall leave a distinct spin signature on the BHs. The BBH that accrete gas quasi-spherically may harden if there is not significant angular momentum loss from the system. Furthermore, these are also ideal conditions for high-redshift Intermediate Mass Black Holes (IMBH) to form. We shall calculate the spin distribution of stellar BHs accreting gas in proto-clusters, calculate the BH mass function following such accretion events, investigate the evolution of separation in accreting BBH in low-metallicity hot turbulent gas, develop theoretical models for the evolution of a BH-subcluster inside proto-clusters and investigate the formation of IMBH. Finally, we shall develop methods for identifying the origin of GW observations, confront our results with LIGO-Virgo-KAGRA data, and investigate synergetically the implications for the GW mission LISA and the X-ray mission Athena.

One of the most energetic events in the Universe is the core-collapse Supernova (SN) where almost all the star's binding energy is released as neutrinos. These particles are direct probes of the processes occurring in the stellar core and provide unique… Read more insights into the gravitational collapse and the neutrino properties. Currently, astroparticle physics is in need of SN observations and of a detection technique highly sensitive to all neutrino flavors. RES-NOVA will revolutionize how we detect neutrinos from astrophysical sources by deploying the first array of cryogenic detectors made from archaeological Pb. Neutrino detection in RES-NOVA is facilitated by the newly discovered Coherent Elastic neutrino-Nucleus Scattering (CEvNS). It enables the first measurement of the full SN neutrino signal, eradicating the uncertainties related to flavor oscillations. To fully exploit the advantages of CEvNS, RES-NOVA ennobles Pb from being a passive shielding to the most sensitive detector component. Pb has the highest cross-section, 10^4 times higher than all used detection channels, enabling the deployment of a cm-scale neutrino observatory. The unconventional approach of RES-NOVA is to use ultra-pure archaeological Pb and run it as a cryogenic detector with low-energy threshold (<1 keV) and unprecedented background (<0.001 c/ton/keV/s). These features also open new opportunities in multi-messenger astronomy, Dark Matter, and neutrino property studies. The success of my pioneer work in operating archaeological Pb-based cryogenic detectors is pivotal for RES-NOVA realization. RES-NOVA will survey 90% of the potential galactic SNe, with only a total detector volume of (30 cm)^3. Future detector upgrades will enhance our SN-sensitivity into the uncharted territory >1 Mpc and increase the SN observation rate. RES-NOVA has the potential to lay the foundations for a future generation of European neutrino telescopes, as all its SN neutrino detectors are currently going offline.

Growing amounts of research data require new computing solutions to manage increased data storage, utilisation, and analysis capabilities. The EU-funded SMARTHEP project will break from the traditional paradigm of ‘first collect data, then analyse it’ and move towards real-time analysis… Read more (RTA) where data collection and analysis become synonymous, so that unprocessed information that would be expensive to store can be discarded. As a consortium formed by academic and industrial partners on scientific, technological, and entrepreneurship aspects of RTA, the project will train a new generation of inter-sector researchers and give them the tools to process large datasets in real-time, aided by machine learning and hybrid computing architectures.

This Implementing Agreement No.1 is a specific agreement to implement the cooperative activities in accordance with Article 2 of the Cooperation Agreement and shall be subject to the terms and conditions thereof, which are incorporated herein by this reference including,… Read more but not limited to, provisions on confidentiality, applicable law and dispute resolution. In avoidance of doubt, the terms and conditions of the Cooperation Agreement take precedence over the other parts of the Implementing Agreement, unless the Cooperation Agreement has specifically allowed for derogation from its provisions.

After the success of the H2020 ESSνSB Design Study proving the feasibility of the upgrade of the European Spallation Source to become, in addition to a neutron facility, also a very competitive neutrino facility, we propose here a study to reinforce… Read more and develop complementary features to this proposal in order to improve and widen the scientific and technological scope. The key objective of the H2020 ESSνSB Design Study was to demonstrate the feasibility of using the European Spallation Source (ESS) proton linac to produce the world's most intense neutrino beam concurrently with the 5 MW proton beam to be used for the production of spallation neutrons. After accomplishing all deliverables and the publication of the ESSνSB CDR, this is now fully demonstrated. With the present Design Study, it is proposed to take further steps towards its realization by introducing complementary studies and enlarging its scope by making studies on synergetic aspects of the project. The ESSνSB+ high-level objectives are to: • Study the civil engineering needed for the facility implementation at the ESS site as well as those needed for the ESSνSB far detector site. • Study the feasibility and implementation of a special target station for pion production and extraction for injection to a low energy nuSTORM decay ring and to a low energy Monitored Neutrino Beam decay tunnel, for neutrino cross-section measurements. • Study the low energy nuSTORM decay ring and the injection of the pions and muons from the special target station. • Study the low energy ENUBET-like Monitored Neutrino Beam decay tunnel and the injection of the pions and muons from the special target station. • Study the capabilities of the proposed setup for sterile neutrino searches and astroparticle physics. • Promote the ESSνSB project proposal to its stakeholders, including scientists, politicians, funders, industrialists and the general public in order to pave the way to include this facility in the ESFRI list.

EUROfusion’s updated Fusion Research Roadmap aims to acquire the necessary knowledge to start constructing a demonstration fusion power plant (DEMO) five years after ITER is in full-power operation. DEMO will deliver fusion electricity to the grid early in the second half of… Read more the century. The Roadmap has been articulated in eight different Missions. The present proposal has the goal of implementing the activities described in the Roadmap during Horizon Europe through a joint programme of the members of the EUROfusion Consortium, with the following high-level objectives: 1. Construct and commission ITER; 2. Secure the success of future ITER operation via preparation and experiments on present devices; 3. Develop the conceptual design of a DEMO fusion power plant; 4. Finalise the design and construct a fusion spectrum neutron source (IFMIF-DONES); 5. Advance the stellarator as an alternative approach to fusion power plants; 6. Prepare the ITER and DEMO generations of scientists, engineers and operators; 7. Promote innovation and European industry competitiveness in fusion technology and beyond. The ITER success remains an important overarching objective of the programme and much attention is devoted to ensure that ITER operation is properly prepared, and that a new generation of scientists and engineers is thoroughly educated and trained for its exploitation. DEMO is the only step between ITER and a commercial fusion power plant. To achieve the goal of fusion electricity demonstration in the early 2050-ies, the DEMO Conceptual Design has to be completed by 2030 at the latest, to allow the start of the Engineering Design Activities. DEMO cannot be defined and designed by research laboratories alone, but requires the full involvement of industry in all technological and systems aspects of the design. Therefore, specific provisions for the involvement of industry in the Consortium activities are envisaged.

In the next few years, electromagnetic and gravitational-wave facilities will uncover the elusive population of intermediate-mass black holes (IMBHs), the likely progenitors of present-day supermassive black holes. The upcoming detections promise to revolutionise our understanding of the black-hole population across the cosmic… Read more epochs; in preparation for this exciting future, it is now fundamental to shed light on the debated dynamical processes governing the growth of IMBHs. TESIFA is the long-awaited program that will clarify the timespan black holes spend in the intermediate-mass range, thus allowing for a solid interpretation of the upcoming IMBH detections. Leveraging the emergent picture according to which IMBHs primarily grow via stellar accretion, TESIFA will numerically model the rates of tidal disruption events (TDEs, thousands of which will be detected by the Vera Rubin Observatory starting next year) and gravitational-wave-induced extreme mass ratio inspirals (EMRIs, accessible to the planned LISA mission) about IMBHs. By combining this approach with state-of-the-art observations of nearby stellar systems, TESIFA will place novel constraints on the local IMBH population. Furthermore, TESIFA will investigate the ratio between TDE and EMRI rates as a function of the host galaxy properties, so that the observed TDE rates could be used to forecast LISA EMRI rates. Overall, TESIFA will lay the foundation for understanding the IMBH demographics and best exploiting their upcoming observations. At Princeton University, the fellow will work alongside world-leading experts in the field of IMBH observations; she will learn the challenges affecting the observations of IMBHs and their hosts, as well as the capabilities and limits of electromagnetic facilities. The planned training will perfectly complement the fellow’s extensive numerical expertise, making her a well rounded scientist and placing her at the forefront of the research targeting IMBHs.

The goal of UNICORN is to develop unprecedented nanocomposite scintillator (SL) detectors based on engineered nanomaterials for transformative breakthroughs in strategic radiation detection areas spanning homeland security and medicine to industrial, nuclear, and environmental monitoring to cosmology and high energy/particle… Read more physics. Today, conventional inorganic SL crystals are prohibitively energy-intensive, fragile, heavy and cannot be produced in large quantities. Organic SLs are, in turn, affordable and scalable, but their low density and light yield reduce energy resolution. These shortcomings preclude progress in application areas of great importance and impose a technological bottleneck to the fundamental study of rare events. The most at risk of all is the study of neutrinoless Double Beta Decay (0νDBD), a so far undetected, rare nuclear process that represents the Holy Grail in particle physics, whose observation would provide long sought-after answers on the origin of the Universe and unlock unexplored scientific territories with unimaginable progress perspectives. UNICORN will tackle this urgent grand challenge by introducing revolutionary nanotechnology-based concepts combining high energy resolution, efficiency, and stability with unmatched mass scalability. The keystone of our disruptive approach are inorganic nanocrystals (NCs) that will be specifically designed to be both the source of 0νDBD and high-performance nano-SLs. The breakthrough will also consist in achieving perfect compatibility with (in)organic hosts to obtain unparalleled ultra-high density optical-grade nanocomposite detectors with maximized light output to be coupled to custom-made light sensors that will embody the archetype of advanced radiation detectors of the future. UNICORN combines world-leading institutions and companies with complementary interdisciplinary competences ensuring the pivotal synergy to reach the project goals and rapidly translate results into economic value.

Gravitational-wave astronomy is entering its large-statistics regime. Catalogs with thousands of gravitational-wave events will soon be available, providing a wealth of information on the most compact objects in the Universe --black holes and neutron stars. These new datasets need new tools to… Read more be exploited effectively in order to maximize their scientific impact. GWmining is an ambitious program to explore upcoming gravitational-wave catalogs with data-mining techniques. We will develop a complete framework to analyze gravitational-wave data in light of astrophysical predictions. Going beyond phenomenological models, we will train machine-learning algorithms directly on large banks of populationsynthesis simulations and post-Newtonian integrations. The development of these astrophysical predictions requires new modeling strategies to accurately capture all the gravitational-wave observables, notably spins and eccentricities. Combined with a hierarchical Bayesian analysis, our neural network will deliver the most stringent measurements to date on elusive phenomena influencing the lives of massive stars. We will constrain phenomena such as binary common envelope, supernova kicks, stellar winds, tidal interactions, etc. Besides harnessing the catalog in its entirety, our complete framework will put us at the forefront to analyze outliers -- golden events with favorable properties of one or more parameters. We will design a complete strategy to exploit the strongest signals to infer exquisite details of the relativistic dynamics of their sources. GWmining is a unique project strategically placed at the intersection of astronomy, data analysis, and relativity. As the large-statistics revolution of gravitational-wave astronomy unfolds, GWmining will pioneer the application of datamining techniques in gravitational-wave population studies, setting the foundations of this booming field for decades.

The direct detection of gravitational waves from binary stellar-mass black hole systems in our Universe provides a wealth of astrophysical information which is now within our reach. These binaries merge in the LIGO and Virgo detector frequency sensitivity bands, and were once… Read more sweeping through the LISA band, emitting at much lower frequencies. In LIGO, the binary mergers appear both as single, resolved events and as a multitude of incoherent signals, known as the stochastic gravitational-wave background. In LISA, a similar picture will be seen, where a few binaries are directly resolved, while the vast majority build up a stochastic signal. With StochRewind, we will draw out all binary black hole information measured by LIGO and Virgo to calibrate the LISA mission, providing a crucial ingredient for LISA data analysis methods. First, we focus on the stochastic background in LIGO, and deliver a brand new pipeline which maximises our chances for detection. Then, we analyse the implications of the LIGO black hole detections and stochastic background for LISA, delivering the first data-based prediction of the LISA binary black hole stochastic background, fully exploiting our multi-band gravitational-wave knowledge. It is essential that StochRewind be hosted by an institute which can supplement the fellow's first-hand experience in stochastic LIGO data analysis with knowledge on black hole population analysis and LISA astrophysics. UniMiB is a unique institution which counts top experts in both these fields, providing an environment which bridges the gap between LISA and LIGO. These revolutionary science objectives will be paired with advanced training objectives tailored to the fellow's personal career development plan, rooted in what UniMiB and the collaborations have to offer. StochRewind will have far-reaching impacts on the community, which will reap the benefits for decades to come.