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QCD jets in matter: new techniques and new measurements

Jets, the observable remnants of energetic quarks and gluons, are fundamental objects in QCD. Jets in elementary collisions provide essential, precise tools for the study of the Standard Model and beyond, thanks to decades of development in both theory and experimental methods. In nuclear collisions at collider energies, jets are used to probe hot QCD matter though modification of their production rates and internal structure. However, jet measurements in the complex environment of nuclear collisions require new techniques, to suppress the huge uncorrelated background in such events without imposing bias on the measured distributions. Indeed, one of the most interesting and sensitive jet measurements in heavy-ion collisions is the secondary scattering of low energy jets in the Quark-Gluon Plasma, which is especially challenging due to very small signal/background. I will discuss new approaches to accurate, unbiased jet measurements over the full jet phase space in nuclear collisions, with application to data from the ALICE experiment at the LHC and the STAR experiment at RHIC. I will also discuss the potential application of these techniques to BSM measurements in proton-proton collisions, in the high luminosity era of the LHC.

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Two particle correlations with identified trigger particles in p-Pb collisions at 5.02TeV

We report results of baryon-hadron and meson-hadron correlations at intermediate pT, where an anomalous enhancement in the inclusive baryon-to-meson ratio has been observed in p-Pb collisions at VsNN = 5.02 TeV. The choice of the trigger pT region (2.0 pT 4.0 GeV/c) is of particular interest as it is believed to have contributions from both hard (fragmentation) and soft (hydrodynamics and/or coalescence model of hadronization) processes of particle production. The associated particles are charged hadrons with 1.0 pT 4.0 GeV/c. Using the two particle correlation technique, the multiplicity evolution of the pion- and proton-triggered jet-like yields has been studied to explore the underlying mechanisms of particle production in the intermediate pT (trigger pT) region.

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Numerical model fully depicting nanoparticle uptake within brain after ultrasound induced Blood-Brain Barrier opening

Low intensity Focused Ultrasound (FUS) combined with microbubbles open the Blood-Brain Barrier (BBB) locally and noninvasively, allowing the passage of nanoparticles into the brain. However, since the quantity of particles that can be delivered with this technique depends on multiple parameters such as tissue properties, particle properties and acoustic parameters, so far a model fully predicting the result of a FUS induced BBB opening experiment is missing. During this seminar, a mathematical model depicting both the vascular permeability as a function of time and the diffusion process occurring in brain tissue will be introduced. This model takes into account acoustic pressure, particle size, blood pharmacokinetics and diffusion rates. It was validated by performing in vivo delivery of nanoparticles with different hydrodynamic diameters in rats. The match with the experimental data proves the feasibility of this novel method to successfully predict and plan drug distribution after a BBB opening experiment.

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Bandi ASI/ESA

Descrizione dei Bandi ASI ed ESA di potenziale interesse INFN. Come partecipare ai Bandi ed accedere ai finanziamenti. Domande e discussione finale.

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The Axiflavon: A Minimal Axion Model from Flavor

I will discuss a simple QCD axion model that arises from identifying Peccei-Quinn with Froggatt-Nielsen symmetries. The flavor problem of the Standard Model is addressed by a U(1) flavor symmetry, which naturally leads to an axion that solves the strong CP problem. The ratio of the axion mass and its coupling to photons is related to SM fermion masses and predicted within a small range, as a direct result of the observed fermion mass hierarchies. The same hierarchies determine the axion couplings to fermions, making the framework very predictive and experimentally testable by future axion and precision flavor experiments.

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Composite Accidental Axions

One of the main problems of axion scenarios is to explain the origin of an almost exact Peccei-Quinn symmetry only broken by the QCD anomaly. In this talk I will present several models where the QCD axion arises accidentally. This can be realised in confining gauge theories where the Peccei-Quinn symmetry can emerge accidentally if the representations are chiral. In some cases these models can be understood as the deconstruction of 5-dimensional gauge theories but more general constructions are possible. Phenomenological features will be discussed.

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Strange and non-strange mesons induced processes studies at DAFNE, J-PARC and RIKEN: present and future

                                                  During the Symposium the strange and non-strange mesons induced processes studies at the DAFNE collider at LNF-INFN, Italy, and at the J-PARC and RIKEN facilities in Japan will be discussed in a unitary framework. The experimental research is focused on several complementary key processes, resulting either from stopped or low-energy kaon induced reactions at the DAFNE collider, from high-energy kaons induced reactions at J-PARC to pionic atoms studied at RIKEN. Studies of kaonic atoms and pionic atoms , of the hyperon-nucleon interactions, as well as the search for deeply bound kaonic nuclear states deliver new constraints on the antikaon-nucleon/nuclei and pion-nucleon/nuclei interactions. Taking advantage of advanced detector systems, such as high precision X-ray detectors, active targets, trackers and calorimeters, and considering the opportunity to use the Italian and Japanese facilities in the coming years, we face the unique chance for resolving the ambiguities and shed new light on the structure of the neutron stars and arrive to a new understanding of the role of strangeness in the Universe. The Symposium is organized with the support of the StrangeMatter (Strangeness in the compact stars? High precision experimental and theoretical studies of the strange matter nuclear interactions at low-energies) project, financed by the Ministero degli Affari Esteri e della Cooperazione Internazionale, Direzione Generale per la Promozione del Sistema Paese.   Organizers: Catalina Curceanu, LNF-INFN (Chair) Kenta Itahashi, RIKEN (Japan) Masahiko Iwasaki, RIKEN (Japan) Fuminori Sakuma, RIKEN (Japan) Alessandro Scordo, LNF-INFN (Italy) Johann Zmeskal, SMI-Vienna (Austria)  

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Charged lepton flavour violation: precise background calculation and effective field theoretical interpretation

This seminar reviews recent theoretical developments in the study of charged lepton flavour violation. The first part illustrates the status of precise next-to-leading order quantum electrodynamics calculations for the background of charged lepton flavour-violating processes, with a focus on the muonic “rare” and “radiative” decays. Phenomenological implications of these computations and their impact on present and future experiments will be discussed. The second part describes the recent progress in the effective field theory interpretation of charged lepton-flavour violating observables in connection with different energy scales. A systematic approach is briefly presented and applications on muonic and tauonic observables are reported.

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HOTNES (HOmogeneous Thermal NEutron Source): A new design of thermal neutron irradiation facility

A new design of thermal neutron irradiation facility, called HOTNES (HOmogeneous Thermal NEutron Source), was prototyped within the INFN-LNF / ENEA-Frascati collaboration. HOTNES is a polyethylene assembly, with about 70 cm × 70 cm square section and 100 cm height, including a large, cylindrical cavity with diameter 30 cm and height 70 cm. The facility is supplied by a 241Am-B source located on the cavity bottom. A specially studied combination of reflecting and attenuating parts produces constant values of fluence rate over irradiation planes as large as 30 cm in diameter. By varying the irradiation plane, the thermal fluence rate can be varied from about 700 cm-2 s-1 to 1000 cm-2 s-1. The facility design, previously optimized by Monte Carlo simulation, was experimentally verified. The main features of the HOTNES facility and the neutron field characterization will be presented.

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