In 2025 IFAE awarded the Severo Ochoa Centre of Excellence accreditation for the third time, recognizing its international leadership in fundamental physics research.

The distinction includes €4.5 million over four years to support its strategic scientific programme and talent development.

New results from the DESI collaboration use the largest 3D map of the universe to trace the effect of dark energy over the past 11 billion years of cosmic history. The analysis combines DESI observations of nearly 15 million galaxies and quasars from its first three years with other cosmological probes such as the cosmic microwave background, supernovae and weak gravitational lensing. Together, these measurements provide new hints that dark energy may evolve with time rather than being a constant, challenging the standard cosmological model.

In 2025, Aurelio Juste, ICREA Research Professor at IFAE, was appointed Physics Coordinator of the ATLAS experiment at CERN. As one of ATLAS’s most senior scientific roles, the position oversees the experiment’s physics programme and the coordination of its scientific results.

In 2025, the ERC Synergy project GravNet began developing the first global detector network dedicated to the search for high-frequency gravitational waves. Led in part by IFAE, the project combines gravitational-wave science with quantum sensing technologies to explore the largely uncharted MHz–GHz frequency range and search for signals linked to fundamental questions such as dark matter, inflation and quantum gravity.

The gravitational-wave signal GW250114 was observed by the two LIGO detectors with a network matched-filter signal-to-noise ratio of 80. We examine Hawking’s area law, also known as the second law of black hole mechanics, which states that the total area of the black hole event horizons cannot decrease with time. A range of analyses that exclude up to five of the strongest merger cycles confirm that the remnant area is larger than the sum of the initial areas to high credibility.

IFAE is responsible for fabricating the ITk pixel modules for the innermost layer, known as linear triplets. This layer is critical for many cornerstone ATLAS analyses, significantly improving tracking resolution and, most importantly, the impact parameter precision—a vital tool for identifying heavy-flavored jets. In 2025, the first production modules featuring the final readout chip (the ITkPixV2 ASIC) were produced and successfully tested in IFAE’s cleanrooms. IFAE is scheduled to produce approximately 130 linear triplet modules (accounting for yield) throughout 2026 and into early 2027.

On October 9th, 2022, space-based observatories such as NASA’s Fermi and Swift detected an extremely bright long Gamma-Ray Burst, GRB 221009A, dubbed the “BOAT” (“Brightest Of All Time”). Although the event occurred during a full moon, preventing immediate observations with Cherenkov telescopes, a dedicated campaign began 32 hours later, making LST-1 the first instrument to observe the source in the very high-energy gamma-ray band. The observations revealed a hint of excess gamma rays and set strong upper limits on the emission, supporting models in which these bursts produce structured, multi-layered jets where particles are accelerated.

The paper “Superinductor-based ultrastrong coupling in a superconducting circuit” reports the first superconducting quantum device fully designed, fabricated and measured at IFAE by the QCT group. The experiment demonstrates ultrastrong coupling between a flux qubit and a resonator using a granular aluminum superinductor, reaching a coupling strength of 13% of the resonator frequency. This result places the device in the perturbative ultrastrong coupling regime and opens the way to future coherent qubit experiments in this regime.

The IFAE Neutrino group contributed to a major result by the T2K Collaboration (Phys. Rev. Lett. 132) reporting the first double-differential measurement of single π⁺ production in neutrino neutral-current interactions on hydrocarbon with the ND280 detector. By mapping the momentum and angular distributions of outgoing pions, the study provides stringent constraints on neutrino interaction models and helps reduce systematic uncertainties that limit precision in oscillation and CP-violation measurements. The analysis, which forms the core of the PhD thesis of César Jesús-Valls, highlights IFAE’s leading role in the reconstruction and interpretation of ND280 data for next-generation neutrino experiments.

Thirteen years after its launch, CosmoHub has released a new frontend featuring a modernized interface and significantly enhanced data visualization capabilities, including improved plotting tools, support for HEALPix maps, and array-based data representation, along with a new Workbench section. Led by Alex Luelmo and Pau Tallada with contributions from the full CosmoHub team, this update marks a key step in the platform’s evolution toward a modern, interoperable environment for multimessenger analysis. The upgrade aligns with a broader roadmap that includes a complete backend API rewrite, integration with PIC’s centralized authentication systems, and the adoption of open standards to advance FAIR data principles and support emerging scientific use cases.

New light scalar or pseudoscalar particles appear in a variety of theoretical models, including extensions of the Higgs sector or scenarios connected to dark matter and the early Universe. At the Large Hadron Collider (LHC), they can be produced in multiple ways like in Higgs decays or in top-associated production, and be detected through their decay into a pair of bottom quarks, thus leading to complex final states containing multiple b-jets. Detecting these signals is particularly challenging because, when the new particle is light, the two bottom quarks can travel very close together and be reconstructed as a single jet.

Using the full Run 2 dataset collected with the ATLAS detector, the IFAE group has conducted two searches for new light particles achieving unprecedented sensitivity to their production. They both use advanced techniques to identify heavy-flavour jets, including dedicated methods for highly collimated decays and for soft secondary vertices produced by the decay of bottom hadrons. The first search targets events with two Higgs bosons decaying into a pair of scalar particles, and produced together with a Z boson decaying leptonically [1]. The second search is the first of its kind performed at the LHC and looks for new particles decaying to a pair of bottom quarks, produced in association with one or two top quarks [2].

No statistically significant evidence for a new particle was found. The analyses nevertheless provide stringent constraints on possible Higgs decays as well as on production cross-section of new light particles in association with top quarks, demonstrating how improved reconstruction techniques and the analysis of larger datasets increase our ability to explore subtle signatures of new physics.

In September 2025, IFAE’s gamma-ray group reached a major milestone at the CERN Super Proton Synchrotron (SPS) during a high-energy beam test campaign. The Scintillating Fiber Tracker (FIT) prototype—the technological cornerstone for a new generation of space-borne observatories—underwent rigorous validation. Utilizing a novel 64-channel ASIC and IFAE-developed electronics, the system successfully recorded over 150 million proton and muon events, providing a massive dataset for performance calibration.

Crucially, IFAE is leveraging this technical success to lead and coordinate an international consortium from Spain, Switzerland, Italy, and Germany in proposing a new mission concept for the ESA Science Programme. By achieving a six-fold improvement in angular resolution and enhanced sensitivity in the 10–100 MeV range, this IFAE-led initiative establishes the technical and leadership readiness required to define the next decade of European high-energy astrophysics from a position of international coordination.

The study “Characterization of Cosmic Radiation for Superconducting Qubit Experiments”, published in New Journal of Physics, reports measurements of cosmic radiation relevant for superconducting quantum devices. Using a portable muon detector, the QCT group characterized cosmic muon flux and its angular dependence at several locations around Barcelona, including IFAE, the Collserola tunnels and the ALBA synchrotron. The results show orientation-dependent energy deposition from cosmic muons, providing constraints for the optimal orientation of superconducting qubit devices to reduce radiation-induced events.

The search for gravitational waves generated by the inspiral phase of binaries of light compact objects holds significant promise in testing the existence of primordial black holes and/or other exotic objects. In this paper, we present a new method to detect such signals exploiting some techniques typically applied in searches for continuous quasi-monochromatic gravitational waves. We describe the signal model employed and present a new strategy to optimally construct the search grid over the parameter space investigated, significantly reducing the search computing cost. Additionally, we estimate the pipeline sensitivity corroborating the results with software injections in real data from the LIGO third observing run. The results show that the method is well suited to detect long-transient signals and standard continuous gravitational waves. According to the criteria used in the grid construction step, the method can be implemented to cover a wide parameter space with slightly reduced sensitivity and lower computational cost or to focus on a narrower parameter space with increased sensitivity at a higher computational expense. The method shows an astrophysical reach up to the Galactic Center (8kpc) for some regions of the parameter space and given search configurations.

Stray light represents a significant noise source for gravitational wave detectors, requiring an accurate modeling and mitigation to preserve the experiment’s sensitivity. In this article, we present an updated and improved analysis of the stray-light induced noise in the Einstein Telescope main arm. The results presented here supersede previous studies taking into account a number of improvements, including baffle clipping effects, new numerical calculations for computing diffraction contributions and the influence of baffle edge serrations. Results are presented for both triangular and L-shaped configurations for the experiment. Furthermore, in the case of the triangular configuration, we examine non-ideal optical cavity conditions, such as beam offsets and misalignments, and the presence of point absorbers in the mirrors, which can increase scattered light noise. This can be translated into future stringent constraints on the design and operating parameters of the interferometer, thus facilitating to achieve its sensitivity targets.

In September 2025, the MAGIC Collaboration organised its first public data-analysis school under the framework of the ACME project (European Research Executive Agency, grant agreement 101131928). A dataset of MAGIC archival observations was publicly released and participants followed hands-on tutorials covering different gamma-ray analysis scenarios using the open-source software Gammapy. Around 50 scientists attended the school each day, while about 100 additional participants accessed the lessons, recordings, data, and software online.