Tag Archives: Evento scientifico

Speaker: Sreemanti Chakraborti (Durham Univ.) In this talk, I will discuss axion-like particles (ALP) as dark matter candidates in the “ultralight mass regime”. On the theory side, I will elaborate on the consistent treatment of QFT of an ALP interacting with Standard Model fields accounting for the renormalisation group running and matching to the low-energy theory. A plethora of quantum sensor experiments has been designed to search for very light ALPs that are particularly sensitive to these effects because they probe large values of the decay constant for which running effects become important. In addition, while linear axion interactions are set by its pseudoscalar nature, quadratic interactions are indistinguishable from scalar interactions. This makes the two types of interactions sensitive to different categories of experiments. I will discuss the reach of various experiments exploiting quantum technology via quantum sensors, haloscopes, helioscopes, and fifth force searches. Lastly, I will discuss the nonlinear behaviour of the ALP field close to the surface of the earth and identify the experiments impacted by this effect.

Speaker: Giovanni Grilli di Cortona (Istituto Nazionale di Fisica Nucleare) Resonant positron annihilation on atomic electrons is a powerful technique for searching for light dark matter particles that couple to e+e-. Accurate estimates of production rates necessitate a detailed characterization of atomic electron momentum distributions. I will present a general method that uses the Compton profile of the target material to accurately account for electron velocity effects in resonant annihilation cross-sections. Additionally, I will discuss the implications of this precise computation for new physics searches and how high Z atoms can effectively serve as electron accelerators, thereby extending the experimental mass reach. Finally, I will demonstrate that leveraging the relativistic velocities of electrons in the inner atomic shells, a high-intensity 12 GeV positron beam — such as the one planned at JLab — can allow to measure the hadronic cross section with high statistical accuracy. This seminar is based on Phys.Rev.Lett. 132 (2024) 26, 261801 and hep-ph/2407.15941. Entra Zoom Riunione https://infn-it.zoom.us/j/98373797903?pwd=ByIdssvPnoY0HWm5hndgibLNeqJNbP.1 ID riunione: 983 7379 7903 Codice d’accesso: 278777

Speaker: Davide Racco (U. Zurich and ETH Zurich) Various production mechanisms for dark matter complement the well-motivated option of freeze-out. The freeze-in scenario is viable for very weakly-coupled particles, which can be looked for in terrestrial experiments. I will discuss how this mechanism is cosmologically viable with respect to the curvature perturbations that it produces on large scales. Another minimal and unavoidable production mechanism for any dark sector is gravitational production during inflation. Its abundance today is determined by the evolution of the dark sector and its interactions during the early Universe. I will discuss as a prototypical example a model of dark QED with a massive mediator, showing how the preferred parameter space complements the one predicted from freeze-in. Finally, I will comment on the misalignment production mechanism for scalars like the axion, and the possible isocurvature constraints for that scenario.   Join Zoom Meeting https://infn-it.zoom.us/j/97845970382?pwd=jwCWjzdWOEvy1mjYH4csZqwD4Ful4x.1 Meeting ID: 978 4597 0382 Passcode: 511907

Speaker: Joel Christopher Swallow (Istituto Nazionale di Fisica Nucleare) The $K \to \pi \nu \bar\nu$ decay is a golden mode for flavour physics. Its branching ratio is predicted with high precision by the Standard Model to be less than $10^{-10}$, and this decay mode is highly sensitive to indirect effects of new physics up to the highest mass scales. The NA62 experiment at the CERN SPS is designed to study the $K^+ \to \pi^+ \nu \bar\nu$ decay, and provided the world’s most precise investigation of this decay using 2016-18 data. Building on this success the first results from a significantly improved analysis of new data, taken in 2021-22 after beam-line and detector upgrades, are presented, as well as the combination with the 2016-18 results.

Speaker: Ian Moult (Yale Univ.) Jets of hadrons produced at high-energy colliders provide experimental access to the dynamics of asymptotically free quarks and gluons and their confinement into hadrons. Motivated by recent developments in conformal field theory, we show that questions of interest in collider physics can be reformulated as the study of correlation functions of a specific class of light-ray operators and their associated operator product expansion (OPE). We show that multi-point correlation functions of these operators can be measured in real collider data, allowing us to experimentally verify the scaling properties associated with the OPE, and providing new insights into the dynamics of the confinement transition, the properties of the quark gluon plasma, and beyond.   Join Zoom Meeting https://infn-it.zoom.us/j/94593192831?pwd=4R3YiT6AQmChZwNaqtUmneJDHUpfEQ.1 Meeting ID: 945 9319 2831 Passcode: 639417

The Workshop on HighLumi-LHC and Hadron Colliders will be held in the Bruno Touschek Auditorium (Bldg. 36, access from LNF secondary entrance in Via E. Fermi, 60 – see map). Inspired by the MCWS  https://virgilio.mib.infn.it/~nason/mcws/scientific_programme.htm organised at LNF on the eve of LHC, and motivated by the 2025-2026 Update of the European Strategy for Particle Physics, we present some topical workshops on future colliders, focused on the opportunities and challenges, both theoretical and experimental, with the goal of informing and blending Italian researchers (of any age bracket) with different backgrounds. Each event will be staged at LNF, which is the birthplace of collider physics and is endowed with large meeting facilities and, beyond the MCWS mentioned above, has a long tradition of events characterised by a strong interaction between theorists and experimenters. Each event will start off with an elementary introduction to the workshop main topics, to be followed by focused talks on specific themes. The setting and the audience will be at the national level, although lecturers may be chosen among world-wide experts. We will start with a workshop on HighLumi-LHC and Hadron Colliders on 1-2-3-4 October 2024, to be followed by a workshop on e+e- Colliders in January 2025, and by workshop(s) on Muon Collider and new horizons, on dates to be defined. The workshop in October will be preceded by a community event dedicated to Early Career Researchers, organized by the Italian members of the ECFA ECR Panel (https://ecfa.web.cern.ch/ecfa-early-career-researchers-panel). Building on the success of the first event held on July 3rd (https://agenda.infn.it/event/42205/), this session will …

There is a strong desire to discuss the future and be included in the process that will shape the next era in high-energy physics. This is a unique opportunity for INFN Early Career Researchers (ECR) to influence the direction of future research and policy, influencing the European Strategy for Particle Physics (ESPP). The event will begin the first day with an introductory talk on proposed future colliders and will then delve into related activities (accelerators, detectors, physics programs) as well as beyond-ECFA topics (as these are also involved in the ESPP). The second day will be dedicated to building an Italian ECR network, aiming to inform, spark discussion, and promote the possibility of a written contribution to the ESPP from Italian ECRs. This community event is dedicated to INFN ECRs and is organized by the Italian members of the ECFA ECR Panel, building on the success of the first event held. Poster Session: Participants who wish to do so are invited to present a poster about their activities or a review of their lab’s activities. Given the heterogeneous nature of the event, the goal of these contributions should be to share information with individuals from other fields. The aim is to foster networking and raise awareness of the work being done by various groups. REGISTRATION DEADLINE: 23 SEPTEMBER 2024 The ECR meeting will be followed by a “Workshop on HighLumi-LHC and Hadron Colliders” focused on the opportunities and challenges, both theoretical and experimental, with the goal of informing and blending …

Speaker: Marco Fedele (Valencia Univ.) In the last decade, several measurements have been hinting at the possibility of Beyond Standard Model physics in B decays. Some of these observables have stayed “anomalous” after several experiments released multiple measurements of such quantities, while others have recently suffered a different fate. In this seminar I will recap the current status of experimental anomalies, critically reviewing the theoretical description of these observables in the Standard Model. I will therefore identify which are the quantities with the highest probability of being affected by New Physics, and which are the ones that on the other hand do not require an extension of the SM any longer.  

Speaker: Alberto Salvio (University of Rome and INFN Tor Vergata) The Standard Model of the strong and electroweak interactions (SM), together with Einstein’s general relativity (GR), is a very successful theory that explains all known interactions between observed particles, including the Higgs boson discovered in 2012. There is, however, no doubt that both the SM and GR need to be extended. I will review some of the most important arguments that show the necessity of extending this standard theory and mention some explicit extensions. I will also discuss what I think is a successful strategy for guessing the right path to go beyond such paradigm: designing models for a vast (possibly infinite) energy range, taking into account all observational bounds from both particle physics and astrophysics. One way to achieve this goal is to construct a viable and UV-complete relativistic field theory of all interactions, which I will illustrate at the end.   Join Zoom Meeting https://infn-it.zoom.us/j/91659585504?pwd=dGPiknLmxfSWC4vVFwUVcLaKFu5ldl.1 Meeting ID: 916 5958 5504 Passcode: 439012

Speaker: Anders Kvellestad (University of Oslo) When we try to navigate the theory space for physics beyond the Standard Model, we need to utilise all the information we can from a wide range of particle and astroparticle experiments. This is the task of BSM global fits — large-scale analyses that confront BSM theories with all relevant experimental data in a statistically rigorous way. In this talk I will discuss why BSM global fits are challenging but important, give an overview of the GAMBIT global fit tool, and show results from some recent GAMBIT studies.