Scientific Open-access Literature Archive and Repository
Not a member yet
16397 research outputs found
Sort by
Upgrade of the LUCID detector for High Luminosity LHC
Full text linkLUCID-2 has been the ATLAS luminometer for the LHC Run-2
data taking (2015-1018), achieving very good performance (0.8% total uncertainty on luminosity) and a similar is expected for Run-3 (2022-2025). But, due to the harsher conditions, the present LUCID won’t be able to operate in HL-LHC. Several proposals for a new detector were made. To test the proposed designs, several prototypes were installed in ATLAS and are under testing. One of these consists in quartz optic fibers that are used both as a Chereknov radiator and as a mean of transport for light. Fibers are read out by a PMT. The novelty of this detector is the double calibration system that is able to monitor both the ageing of the fiber and the PMT gain. In this contribution the first results obtained with the fiber prototype in LHC Run-3 are presented. The first results obtained by an irradiation session and a beam test to characterize the fibers are also discussed
Advancing High-Energy Physics through Machine Learning: Current state and future prospects
Full text linkRecent advancements in AI and Machine Learning are having re
markable results in the field of High Energy Physics. The growing adoption of Transformer architectures make it easy to build and innovate from industry developments, while the community is increasingly looking to foundation models as the
next promising approach. The following work is a brief review of current innovations and an outlook of possible future developments
Anomaly Detection approach for the search of new resonances with fully hadronic final state
Full text linkIn recent years, the exploration of Beyond Standard Model phenomenology has become more and more important. One approach to handle this new hard challenge is to look at the data with minimum assumptions on the model, using Anomaly Detection (AD) techniques. Here, a novel application of AD is used to define a general signal region, where events are selected solely because of their in compatibility with a learned background-only model. Further, as an example of the
possible approach of AD an application on a benchmark dataset of the unsupervised learning approach using Graph Neural Networks is presented
EU BlueMissionMed, 2025. Depolluting the Mediterranean: A 2030 roadmap for key economy sectors to fulfil the EU Mission to ‘Restore our Ocean and Waters’ through Innovative and Transformative Solutions
Full text link2030 is a landmark year for the European Union: it’s the target date
for member states to bring concrete solutions to some of the greatest
challenges we face as a global society. To this end, five EU Missions are
ongoing under Horizon Europe, the bloc’s key funding programme for
research and innovation. Mission 3 is to ‘Restore our Ocean and Waters’.
This has three specific objectives, the second of which is to ‘Prevent and
eliminate pollution in our seas and ocean’
Intelligenza artificiale e ricerca scientifica. Quale governance per le nuove tecnologie nella conduzione della ricerca scientifica
Full text linkLo sviluppo e la rapida diffusione dei sistemi di Intelligenza Artificiale (AI), in
particolare quelli legati all’apprendimento profondo, all’intelligenza artificiale
generativa e ai modelli di base, pongono quesiti complessi in tema di governance
della ricerca scientifica.
La crescente integrazione dell’AI in molte delle attività intellettive sta modificando in profondità anche il modo di fare ricerca, intervenendo su fasi essenziali come la
raccolta e l’analisi dei dati, la modellazione teorica e la pubblicazione dei risultati. Ciò significa che le discussioni sorte attorno all’autoapprendimento, all’autonomia e alla creatività dei sistemi di AI, tra le altre, non possono rappresentare soltanto l’oggetto d’indagine della ricerca ma devono essere poste al centro delle riflessioni dei policymaker, per stimolare scelte di governance a tutela della libertà della scienza. In questo contesto, la comunità scientifica è chiamata a dotarsi di policy che diano un’attenzione adeguata a tali questioni, per assicurare che la ricerca scientifica continui a rappresentare quella dimensione etico-sociale in cui garantire “il pieno sviluppo della persona umana”
Wigner density approach to quarkonium production in high energy pp collisions
Full text linkThe production of charmonium and bottomonium states in pp collisions is studied using the Wigner density formalism. For practical purposed the Wigner density of the quarkonia is approximated by analytical 3-D isotropic harmonic oscillator Wigner densities with the same root-mean-square radius as the wave function, which is given by the solution of the Schrodinger equation. This approach reproduces quite well the available experimental transverse momentum and rapidity
distributions
Heavy flavour hadronization from AA to pp collisions
Full text linkOne of the current challenges in understanding heavy-quark
hadronization lies in interpreting measurements of heavy baryon production across various collision systems like AA, pA, and pp collisions. Predictions based on coalescence and fragmentation hadronization approaches have shown a baryon/meson ratio Λc/D0 on the order of unity in AA collisions. This was initially observed at RHIC energies and more recently in pp, pA, and AA collisions at the LHC
energies. The ratio in smaller collision systems suggests a significant departure from that observed in elementary collision systems, where the Λc/D0 ratio is typically on the order of 10−1. We present an hadronization mechanism based on the coalescence and fragmentation processes. We show that within this model it is possible describe several observables involving heavy-flavour hadrons from AA collision to pp collisions. The results suggest that a description of charmed hadron production in smaller systems like in pp collisions require the assumption of an hot QCD medium. Furthermore, we will explore particle yields of multi-charmed baryons like Ξcc,Ωcc and Ωccc. Finally, we discuss the charmed and multi-charmed hadrons production
in PbPb collisions within the 0−10% centrality class and furthermore we show the predictions of multi-charmed hadrons in different collision systems like Pb+ Pb, Kr+Kr, Ar+Ar and O+O
Non-equilibrium effects and spherocity in relativistic proton-nucleus collisions
Full text linkWe examine non-equilibrium dynamics in proton-nucleus collisions at LHC energy by comparing the Parton-Hadron-String-Dynamics (PHSD) transport approach with the (2+1)dimensional viscous hydrodynamic model VISHNew. The
latter is initialized with initial conditions extracted from PHSD. We observe that PHSD exhibits highly inhomogeneous energy density profiles on the transverse plane throughout the evolution, while VISHNew efficiently smooths initial spatial irregularities yet maintains significant inhomogeneity due to the smaller space-time size of the medium produced in small systems compared to heavy-ion reactions. The two approaches present also a very different evolution of the bulk viscous pressure. Furthermore, we analyze transverse spherocity distribution in PHSD and the hybrid approach (VISHNew + hadronic afterburner). We find a shift towards isotropic event configurations in PHSD compared to the result of the hybrid model. This dis
similarity should primarily arise from the different descriptions of the medium within the two frameworks. We support the utility of multi-differential measurements based on multiplicity and spherocity selection for studying final-state observables in relativistic proton-nucleus collisions
Searching for internal pair creation anomalies and the X17 boson at LNL
Full text link2016,a breakthrough anomaly was reported in the isoscalar magnetic dipole transition in 8Be via the Internal Pair Creation process. An unexpected angular distribution of the relative angle of the e+e− was measured at the Atomki
Laboratory. This phenomenon was explained considering the assumption of an emission of a neutral boson, named X17, with a mass of 16.70±0.35(stat)±0.5(syst) MeV/c2 and Jπ =1+. This finding triggered a global campaign to search for the new boson claimed. In Italy, at the Legnaro National Laboratories, a novel scintillator detector array has been designed and built. The present work reports the status of
the first in-beam experiments performed in 2023 and 2024
Correlation function studies at intermediate energies at CSHINE
Full text linkThe isospin-dependent nuclear equation of state, i.e. symmetry energy Esym(ρ) plays an important role in the study of nuclear physics and astrophysics. In terrestrial lab, heavy-ion reaction provides a unique way to constrain
Esym(ρ). So a compact spectrometer for heavy ion experiment (CSHINE) is built and particle correlation functions are measured. The HBT correlation function method is applied as an chronometer to extract the emission timescale and
determine the emission order of hydrogen isotopes from the intermediate velocity source formed in 30MeV/u40Ar +197 Au. The proton emission timescale τp ≈ 100 fm/c is extracted by the fit of Koonin-Pratt equation with correlation after burner (CRAB) code. And the dynamic emission order of τp >τd >τt is evidenced via the correlation functions of nonidentical particle pairs, indicating that the neutron rich particles are emitted earlier. Meanwhile, transport model simulations demonstrate that the emission timescale of isospin dependent particles depends on the density slope
parameter of the nuclear symmetry energy. And the isospin chronology provides a promising route to study the symmetry energy and isospin relaxation