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European Contributions to Fermilab Accelerator Upgrades and Facilities for the DUNE Experiment
No full textThe Proton Improvement Plan (PIP-II) to the FNAL accelerator chain and the Long-Baseline Neutrino Facility (LBNF) will provide the world's most intense neutrino beam to the Deep Underground Neutrino Experiment (DUNE) enabling a wide-ranging physics program. This document outlines the significant contributions made by European national laboratories and institutes towards realizing the first phase of the project with a 1.2 MW neutrino beam. Construction of this first phase is well underway. For DUNE Phase II, this will be closely followed by an upgrade of the beam power to > 2 MW, for which the European groups again have a key role and which will require the continued support of the European community for machine aspects of neutrino physics. Beyond the neutrino beam aspects, LBNF is also responsible for providing unique infrastructure to install and operate the DUNE neutrino detectors at FNAL and at the Sanford Underground Research Facility (SURF). The cryostats for the first two Liquid Argon Time Projection Chamber detector modules at SURF, a contribution of CERN to LBNF, are central to the success of the ongoing execution of DUNE Phase I. Likewise, successful and timely procurement of cryostats for two additional detector modules at SURF will be critical to the success of DUNE Phase II and the overall physics program. The DUNE Collaboration is submitting four main contributions to the 2026 Update of the European Strategy for Particle Physics process. This paper is being submitted to the 'Accelerator technologies' and 'Projects and Large Experiments' streams. Additional inputs related to the DUNE science program, DUNE detector technologies and R&D, and DUNE software and computing, are also being submitted to other streams
Quantum Information meets High-Energy Physics: Input to the update of the European Strategy for Particle Physics
No full textSome of the most astonishing and prominent properties of Quantum Mechanics, such as entanglement and Bell nonlocality, have only been studied extensively in dedicated low-energy laboratory setups. The feasibility of these studies in the high-energy regime explored by particle colliders was only recently shown and has gathered the attention of the scientific community. For the range of particles and fundamental interactions involved, particle colliders provide a novel environment where quantum information theory can be probed, with energies exceeding by about 12 orders of magnitude those employed in dedicated laboratory setups. Furthermore, collider detectors have inherent advantages in performing certain quantum information measurements and allow for the reconstruction of the state of the system under consideration via quantum state tomography. Here, we elaborate on the potential, challenges, and goals of this innovative and rapidly evolving line of research and discuss its expected impact on both quantum information theory and high-energy physics.Some of the most astonishing and prominent properties of Quantum Mechanics, such as entanglement and Bell nonlocality, have only been studied extensively in dedicated low-energy laboratory setups. The feasibility of these studies in the high-energy regime explored by particle colliders was only recently shown and has gathered the attention of the scientific community. For the range of particles and fundamental interactions involved, particle colliders provide a novel environment where quantum information theory can be probed, with energies exceeding by about 12 orders of magnitude those employed in dedicated laboratory setups. Furthermore, collider detectors have inherent advantages in performing certain quantum information measurements, and allow for the reconstruction of the state of the system under consideration via quantum state tomography. Here, we elaborate on the potential, challenges, and goals of this innovative and rapidly evolving line of research and discuss its expected impact on both quantum information theory and high-energy physics
Experimental review of the EFT MC modeling details for HH
No full textReview of di-Higgs Effective Field Theory Monte-Carlo (MC) modeling which gives an overview that highlights models, modeling of MC and challenges in this are
Measuring the system size dependence of the strangeness production with ALICE
No full textThe system size dependence of strangeness production in highenergy collisions was studied using Run 2 data from the ALICE experiment at the LHC. The analysis examines the ratios of strange hadron yields to pion yields as a function of mid-rapidity charged particle multiplicity ⟨dNch/dη)|η|&0.5, offering insights into the mechanisms driving strangeness enhancement across different collision systems (pp, p–Pb and Pb–Pb). The yield ratios exhibit a continuous rising trend from low-multiplicity pp collisions at √s = 7 TeV to central Pb–Pb collisions at √sNN = 5.02 TeV. Additionally, the evolution of the mean transverse momentum (⟨pT⟩) for various strange hadrons (KS0, Λ(Λ¯), Ω±, Ξ±) is analyzed, revealing that ⟨pT⟩ does not connect smoothly between different collision systems, with harder spectra observed in high-multiplicity pp collisions compared to the peripheral Pb–Pb collisions. Finally, performa plots from LHC Run 3 are presented, showcasing the purity of Ξ− and Ω− invariant mass distributions and highlighting the enhanced detector capabilities in Run 3
How Accidental was Inflation?
No full textData on the cosmic microwave background (CMB) are discriminating between different models of inflation, disfavoring simple monomial potentials whilst being consistent with models whose predictions resemble those of the Starobinsky R + R cosmological model. However, this model may suffer from theoretical problems,since it requires a large initial field value, threatening the validity of the effective field theory. This is quantified by the Swampland Distance Conjecture, which predicts the appearance of a tower of light states associated with an effective ultra-violet cutoff. This could be lower than the inflation scale for cases with an extended period of inflation, leading to an additional problem of initial conditions.No-scale supergravity models can reproduce the predictions of the Starobinsky model and accommodate the CMB data at the expense of fine-tuning of parameters at the level of 10. Here, we propose a solution to this problem based on an explicit realisation of the Starobinsky model in string theory, where this `deformation' parameter is calculable and takes a value of order of the one corresponding to the Starobinsky inflaton potential. Within this range, there are parameter values that accommodate more easily the combination of Planck, ACT and DESI BAO data, while also restricting the range of possible inflaton field values, thereby avoiding the swampland problem and predicting that the initial conditions for inflation compatible with the CMB data are generic.Data on the cosmic microwave background (CMB) are discriminating between different models of inflation, disfavoring simple monomial potentials whilst being consistent with models whose predictions resemble those of the Starobinsky cosmological model. However, this model may suffer from theoretical problems, since it requires a large initial field value, threatening the validity of the effective field theory. This is quantified by the Swampland Distance Conjecture, which predicts the appearance of a tower of light states associated with an effective ultra-violet cutoff. This could be lower than the inflation scale for cases with an extended period of inflation, leading to an additional problem of initial conditions. No-scale supergravity models can reproduce the predictions of the Starobinsky model and accommodate the CMB data at the expense of fine-tuning of parameters at the level of . Here, we propose a solution to this problem based on an explicit realisation of the Starobinsky model in string theory, where this `deformation' parameter is calculable and takes a value of order of the one corresponding to the Starobinsky inflaton potential. Within this range, there are parameter values that accommodate more easily the combination of Planck, ACT and DESI BAO data, while also restricting the range of possible inflaton field values, thereby avoiding the swampland problem and predicting that the initial conditions for inflation compatible with the CMB data are generic
Performance and longevity of ATLAS RPCs with new lower GWP mixtures
No full textResistive Plate Chambers (RPCs) are critical components of the muon systems of most HL-LHC experiments. Until 2023, all HL-LHC RPC systems used a so-called standard mixture (STD), consisting of 94.7\% CHF (Tetrafluoroethane - R134a), 5\% i-CH (Isobutane), and 0.3\% SF (Sulfur Hexafluoride), highly tuned for RPC performance but having very high global warming potential (GWP). The environmental impact and the increasing difficulty in procuring these types of fluorinated gases imposes to pursue a solution for the long-term experiment plans, such as a new mixture having a lower GWP and preserving, as well, the detector performance and longevity. In the last 2 years, ATLAS muons have been following such strategy, progressively replacing TFE (GWP: 1430) with CO (GWP: 1), and validating the choice with extensive ageing tests performed on realistic ATLAS RPC prototypes. This led ATLAS to be the first experiment replacing the RPC gas mixture in July 2023 with a new mixture, where 30\% of TFE has been replaced with CO; the ATLAS RPC system behavior has been since then studied carefully, to spot in vivo any eventual sign of accelerated ageing. More challenging perspectives, presently under validation, prior to apply them in the experiment, include a further reduction of TFE to 40\%, and a lowering, or a total replacement of SF, which GWP (23800) is extremely high. We will report the experience of this 2-year-long performance and longevity study, including the results of one full HL-LHC year of the ATLAS RPC system with the new gas