Physics seminars

1 Jan 2026, 15:00 → 31 Dec 2026, 17:00 Europe/Rome

Room 412 C - Ferrara

Tuesday 27 January

15:00 → 16:00 A Roadmap to Strong-Field QED: Concepts, Experiments, and the LUXE Program

Strong-field QED describes the interaction of charged particles and photons with electromagnetic fields so intense that non-linear and non-perturbative effects become experimentally accessible, enabling phenomena such as non-linear Compton scattering and non-linear Breit–Wheeler pair production. These effects are not only of fundamental interest in the laboratory but are also relevant to extreme astrophysical environments, such as the magnetospheres of neutron stars. This talk provides a roadmap of strong-field QED, introducing the key concepts and physical regimes and reviewing the main experimental approaches pursued today, including crystals, beam–beam interactions, and collisions between electrons or photons and high-intensity laser pulses. Particular emphasis is placed on the LUXE experiment at DESY, which will probe this regime with high precision using the 16.5 GeV electron beam of the European XFEL and an ultra-intense optical laser. Finally, the potential of high-energy photons from strong-field interactions for beam-dump–type new physics searches is discussed.

Speaker: Ivo Schulthess (ETH Zurich)

Wednesday 4 February

11:00 → 12:00 Euclid Q1 galaxy clustering and its cross-correlations with CMB lensing

Combining Cosmic Microwave Background (CMB) and large-scale structure (LSS) observations provides a powerful way to probe the evolution of the Universe from recombination to the present day, test gravity on cosmological scales, and constrain the nature of dark matter and dark energy. In this talk, I present the first measurements of galaxy clustering from the Euclid Q1 data release and its cross-correlation with CMB lensing convergence maps from Planck and the Atacama Cosmology Telescope. We detect the signal at high significance and find excellent agreement with expectations from simulations and the Planck 2018 cosmological model. I will discuss robustness tests against observational systematics, tomographic measurements, and early constraints on galaxy bias and redshift uncertainties. These results demonstrate the strong potential of Euclid–CMB cross-correlations to deliver robust cosmological constraints and to mitigate systematics in future Euclid data releases.

zoom: https://cern.zoom.us/j/65644266180?pwd=xdfyl67pQ0zfWjyFui5klxnsSRb8WZ.1

Speaker: Margherita Lembo (IAP, Paris, France)

Friday 6 February

10:00 → 11:00 Cosmic strings and domain walls: CMB constraints and the role of B-modes

Cosmic strings and domain walls are topological defects arising from the spontaneous breaking of new symmetries in the early Universe, as predicted in several beyond the Standard Model scenarios. In this talk, I will briefly introduce the physics of defect networks and discuss their impact on cosmological observables, with particular emphasis on their signatures in the Cosmic Microwave Background. I will then present constraints derived from current CMB data, highlighting in particular the role of B-mode polarization. Finally, I will outline prospects for upcoming CMB experiments and their potential to significantly improve sensitivity to topological defects.

zoom: https://cern.zoom.us/j/64532006687?pwd=Bj4hXXbb2t6MZnFlXq0vCTE4EPXrPu.1

Speaker: Luca Caloni (Universidade de Coimbra, Coimbra, Portugal)

Friday 13 February

14:30 → 15:30 Coincidence and anti-coincidence gamma ray spectroscopy in radionuclide identification

The two most challenging aspects of gamma ray spectrometry are to achieve spectral free interferences and to attain the lowest possible detection limits and ultimately low uncertainties. In nuclear forensics isotopic ratios or elemental ratios in environmental analyses need to have the individual results at low uncertainties for meaningful interpretations. Over the last decades gamma-gamma coincidence and anti-coincidence (Compton suppression) methods have been used for variety radionuclide identifications for passive counting of naturally occurring radioactive material (NORM), special nuclear materials (239Pu), fission products and neutron activation analysis (NAA) for environmental, geological, and biological samples. One real major advantage of these methods is that spectral interferences can be significantly reduced as in the case of Compton suppression or be eliminated as in gamma-gamma coincidence, while also reducing the Compton continuum and decreasing detection limits. For instance, the determination of 137Cs in soil with Compton suppression can be determined at less than 1 Bq/kg for only a twenty-gram sample. In neutron activation analysis elements such as arsenic and cadmium in biological specimens can be determined with detection limits at the ng/g level, which cannot be determined using traditional NAA methods. There are a host of elements determined by NAA that have benefitted using gamma-gamma coincidence and anti-coincidence methods. And in many cases, elements that are seldom or never reported, can now be effectively determined incorporating epithermal neutrons where the resonance integrals for several elements are high. An overview of these methods will be delineated with specific examples.

Zoom: https://cern.zoom.us/j/68713119184?pwd=HbCsVLUEbBC7JtpriZza6iUr5OylYN.1

Speaker: Prof. Sheldon Landsberger (Nuclear and Radiation Engineering Program Walker Department of Mechanical Engineering University of Texas at Austin, USA)

Friday 6 March

11:00 → 12:00 CHRONOS: A Cryogenic Sub-Hz Torsion-Bar Speed-Meter for Stochastic Gravitational-Wave Background Searches

Abstract: The sub-Hz frequency band represents one of the last unexplored frontiers in gravitational-wave (GW) astronomy. Access to this regime opens a unique observational window onto cosmological stochastic gravitational-wave backgrounds (SGWB), early-Universe phase transitions, cosmic strings, and low-frequency compact binaries beyond the reach of current ground-based interferometers.
In this talk, I will present CHRONOS (Cryogenic sub-Hz cROss torsion-bar detector with quantum NOn-demolition Speed meter), a novel interferometric concept designed to probe the 0.1–10 Hz band from the ground. CHRONOS combines a cross torsion-bar topology with a Sagnac speed-meter configuration, implementing quantum non-demolition (QND) measurement principles to suppress radiation-pressure noise at low frequencies. In contrast to conventional position-meter Michelson interferometers, the rotational speed-meter observable intrinsically modifies the quantum noise coupling, enabling stable low-frequency performance. By operating cryogenic sapphire test masses, the detector further reduces thermal noise and aims to achieve quantum-noise-limited sensitivity in the sub-Hz regime. I will first outline the interferometer topology and the associated quantum-noise behavior that distinguish rotational speed-meter measurements from traditional configurations. I will then present the projected sensitivity and noise budget of CHRONOS, highlighting the achievable performance in the sub-Hz band.
Finally, I will discuss the prospects for stochastic gravitational-wave background searches, including sensitivity projections to cosmological models. CHRONOS provides a complementary path toward extending terrestrial gravitational-wave detection into the sub-Hz domain, bridging the frequency gap between existing ground-based detectors and future space missions, and opening new opportunities for probing fundamental physics and cosmology.

zoom: https://cern.zoom.us/j/63349754507?pwd=TbxHYvQV1jCX5YIHHDYYfua1DdEwpP.1

Speaker: Yuki Inoue (National Central University, Taiwan)

Tuesday 10 March

15:00 → 16:00 Fundamental Physics with Cosmic Microwave Background Observations

Particle cosmology aims to uncover the fundamental laws of physics that govern the Universe. Our research today is driven by five outstanding mysteries: cosmic inflation, baryon asymmetry, neutrino properties, dark matter, and dark energy. In addition, two recent observational hints—possible parity violation in cosmological signals and indications of dynamical dark energy—suggest that new physics may be within reach. Resolving any of these questions would profoundly transform particle physics and our understanding of the Universe.
Among the many observational probes, measurements of the cosmic microwave background (CMB) play a key role. After reviewing past CMB observations, I will introduce the projects I am currently involved in, with particular emphasis on the Simons Observatory and LiteBIRD. I will conclude by discussing the emerging synergy between CMB measurements and gravitational-wave observations, and how their combination may open new windows onto fundamental physics.

Zoom: https://cern.zoom.us/j/67644485998?pwd=xWBE2XzKEioRiXMwMCnaAxGMXJ7LXG.1

Speaker: Masashi Hazumi (INFN Visiting Scientist on leave from KEK/IPNS Tsukuba)

Tuesday 7 April

14:00 → 15:00 Beyond the Cosmological Constant: The Dark Energy Quest

Understanding the nature of dark energy remains one of the central challenges in modern cosmology. In this seminar, I will present recent advances in probing extensions to the standard ΛCDM model using both observational and theoretical approaches. First, I discuss interacting dark energy models in which dark matter and dark energy interact non-gravitationally. In particular, I will highlight the importance of redshift space distortion measurements in narrowing the allowed parameter space, providing tight constraints on the interacting dark energy model considered. I then present a model-independent study of the cosmic evolution of dark energy using a non-parametric reconstruction method. Given the degeneracies between dark energy and neutrinos, we use the same formalism to reconstruct also the sum of neutrino masses. Our analysis indicates that deviations from a cosmological constant are generally small, though certain data combinations allow for phantom‑like dark energy evolution with implications for neutrino mass bounds. Together, these studies highlight the power (and importance) of combining different measurements to break degeneracies when trying to constrain a cosmological model.

Zoom link: https://cern.zoom.us/j/63414047463?pwd=OAuE7B2AAjxU3ZPNr43sxuxdku3xQU.1

Speaker: Pietro Ghedini

Thursday 16 April

11:00 → 12:00 Co-propagating dielectric laser accelerators for compact high-gradient particle acceleration

Dielectric Laser Accelerators (DLAs) are a promising approach for compact particle acceleration based on infrared lasers interacting with nanostructured dielectric materials. Operating at optical frequencies, these structures can sustain accelerating gradients well beyond the limits of conventional radio-frequency accelerators while enabling a drastic reduction of accelerator dimensions. Recent developments focus on extended dielectric waveguide structures supporting co-propagating electromagnetic modes synchronized with charged particle beams. This configuration enables longer interaction lengths and improved scalability compared with conventional transverse illumination schemes. This contribution presents recent advances in the design, modeling, and experimental investigation of dielectric interaction structures for particle acceleration in both sub-relativistic and relativistic regimes. Physics-based design methodologies and figures of merit for hollow-core dielectric waveguides are discussed, together with integrated beam dynamics simulations enabling co-design of electromagnetic structures and particle acceleration. This work is carried out within the European project EPITA (WP5: laser-driven acceleration) and within the INFN CSN5 iDLA project.

zoom: https://cern.zoom.us/j/65647993989?pwd=ZBbo2rTJJL2PHUEz6ETTdJeea45c4O.1

Speaker: Giuseppe Torrisi (Istituto Nazionale di Fisica Nucleare)

Tuesday 28 April

11:00 → 12:00 Understanding the Gamma-Ray Burst Diversity with Data-Driven Methods

Gamma-ray bursts (GRBs) exhibit extraordinary diversity in their light curve morphologies and spectral characteristics, reflecting the complex physics of relativistic outflows and radiation mechanisms operating under extreme conditions. Traditionally, this diversity has been reduced to a small number of phenomenological classes (e.g., long vs. short, Type I vs. Type II); however, mounting observational evidence challenges these binary classification schemes and exposes their physical limitations. In this talk, I will explore whether GRB diversity can be leveraged as a diagnostic of underlying physical processes rather than treated as observational scatter, using a data-driven framework that combines unsupervised machine learning with prompt emission pulse characteristics. I will focus in particular on ongoing efforts to interpret the feature-space clusters identified by dimensionality reduction and clustering algorithms, and to assess whether these groupings trace meaningful physical differences in jet physics, radiation mechanisms, or progenitor properties, or instead arise from degeneracies in the observational parameter space.

zoom: https://cern.zoom.us/j/64371309380?pwd=bUbpQazzFgZoWUkSOmV0IhZxrvkiAZ.1

Speaker: Dimple (U. Birmingham, UK)

Thursday 14 May

09:00 → 13:00 Giornata Internazionale della Luce 2026

9:00 -9:30 Registrazione
9:30 - 9:35 Apertura Seminario
9:35 - 10:35 Prof. Boscherini “I sincrotroni e laser a elettroni liberi: sonde di avanguardia in fisica della materia”
10:35 - 11:05 Pausa caffè con buffet
11:05 - 11:50 Prof. Vincenzi “Concentratori solari a luminescenza e fotovoltaico: guidare la luce per la conversione solare“
11:50 - 13:00 Visita ai laboratori
Lab Fotovoltaico: Concentratori solari a luminescenza Spettroscopia di assorbimento a raggi X su elettrodi in Germanio poroso
Lab Sensori: Sensori a stato solido, Spettroscopia infrarossa in riflettanza diffusa (DRIFT)

Speakers: Prof. Donato Vincenzi (Dipartimento di Fisica e Scienze della Terra, UniFe), Federico Boscherini (DIFA - Department of Physics and Astronomy, University of Bologna)

Tuesday 19 May

14:30 → 15:30 Bio-Inspired Artificial Spider Silk Fibers: Promise and Pitfalls in Sustainable Textile Development

The global reliance on petroleum-based fibers has created a major sustainability challenge, particularly within the fashion industry, where durability and low cost often come at significant environmental expense. Natural alternatives such as silkworm silk offer partial solutions, yet their current production systems remain resource-intensive and difficult to scale sustainably. Spider silk, renowned for its exceptional mechanical properties, provides a compelling biological model; however, farming spiders is inherently impractical, limiting its direct industrial application.
Recent advances in bio-inspired materials science are opening new pathways through the development of synthetic bio-based fibers that emulate the structure and performance of natural silks while enabling scalable production. This seminar will present an overview of the latest progress in the design and processing of bio-inspired spider silk fibers, highlighting how interdisciplinary approaches are driving the transition toward truly sustainable textile materials.

About the speaker: Gabriele Greco received his bachelor and master degree in physics from the University of Ferrara and his Ph.D. in mechanical engineering from the University of Trento. He is currently a lecturer of “Experimental Mechanics” and post-doctoral researcher at the University of Pavia and his research interests focus on the mechanics of protein-based materials, particularly focusing on artificial silk structures. His passion for spiders led him to co-found the Italian Society of Arachnology - Aracnofilia, in which he serves as vice president.

Zoom: https://cern.zoom.us/j/69974978314?pwd=IfI7uTTsL73OiNSbzZvXDcuGN4Hdbp.1

Speaker: Gabriele Greco (Pavia University)