Tag Archives: Evento scientifico

L’11 Aprile presso l’Aula Salvini edificio Alte Energie dalle 10:50 faremo il secondo incontro dedicato ad attività che coinvolgono il Laboratorio DAFNE-Luce. Le presentazioni saranno legate alle attività nell’ambito dei beni culturali che coinvolgono il laboratorio.  

The John Adams Institute for Accelerator Science is a centre of excellence in the UK for advanced and novel accelerator science, research, and technology, providing expertise and training in accelerator techniques, and promoting advanced accelerator applications in science and society. In particular I will be talking about development of the single shot, femtosecond resolution capable “time-profile” beam diagnostics and THz source of coherent radiation. I will also present the most recent achievements in development of dual-axis cavity for energy recovery high average LINACs.

The interplay between precise theory predictions and experimental measurements has written a success story in particle physics. After a brief journey into history we will review recent developments which have led to “revolutions” with regard to precision calculations in perturbative quantum field theory. The second part of the talk will focus on particle physics phenomenology, in particular on the Higgs sector, which may be a window to physics beyond the Standard Model.  

  The endless number of theories predicting new physics beyond the Standard Model presents a huge challenge to physicists at the LHC. How do we make sure we don’t miss the signs of new physics in the data? I will discuss the three main approaches we take to look for needles in the LHC data-haystack: precision Standard Model measurements, searches for new resonances, and searches for excesses in tails of kinematic distributions. I will focus on some of the most recent and exciting results, and also show you how the many null results can be useful to the wider physics community.

In this talk I will discuss some theoretical subtleties of the top-quark mass determination, issue which persists in being highly controversial. In the first part of the talk I will compare several NLO generators for top-pair production implemented in the POWHEG BOX framework, that differ by the level of accuracy employed to describe the top decay. The impact of the shower Monte Carlo programs, used to complet the NLO events generated by POWHEG BOX, is also studied. In particular, I discuss the two most widely used shower Monte Carlo programs, i.e. Pythia 8.2 and Herwig 7.1, and how it is possible to interface them with processes that contain decayed emitting resonances. The second part is instead devoted to the study of linear renormalons in observables that can be employed to determine the top mass.

Electromagnetic form factors give Lorentz invariant information about the electromagnetic charge distributions inside hadrons. They are thus a key probe of the dynamics of QCD in the low energy, non-perturbative regime. Importantly, it is well known that due to its characteristically light mass, the pion plays an important role in low energy observables. In particular, the effects of implementing pion loop corrections at the hadron level (as opposed to the quark level) will be discussed. I will show results for electromagnetic form factors calculated in the NJL Model, and in particular, that one obtains am improved prediction of the predicted Hyperon Magnetic moment when the pion loop effects are implemented in this way. One important input into this calculation is the pion form factor itself. Modern extractions of the pion form factor for moderate values of the photon virtuality (above about 0.3 GeV^2) arise from a model dependent extraction from pion electro-production data. In the second half of the talk, a simple model of pion electro-production, will be described and used to examine the model dependence of the extraction method. In the context of this simple model, the extracted form factor is systematically overestimated.

I present a brief overview of some novel detection strategies for ultra-low-mass bosonic dark matter that forms a coherently oscillating classical field. Possible effects of such dark matter fields include time-varying spin-precession effects and time-varying fundamental constants. These effects can be sought with various low-energy atomic and astrophysical probes, including magnetic resonance techniques, spectroscopy measurements, microwave/optical cavities (maser/laser interferometers), fifth-force experiments, and Big Bang nucleosynthesis. Further possible effects of dark bosons include the mediation of anomalous new forces that can be sought with electric dipole moment experiments, parity non-conservation experiments and (antimatter) spectroscopy measurements. Existing and new experimental and observational data have allowed us and other groups to improve on previous observational bounds on dark matter and dark boson interactions by many orders of magnitude.

  Yang-Mills fields present scale invariance, what allows the theory to be renormalized. In this talk we show that fractal structures can be formed by fields described by this theory. Such fractal structure allow for recursive equations that enable the calculation of high order perturbative calculations. In addition, it leads to  power-law distributions of energy and momentum, and therefore explains the emergence of the non extensive Tsallis statistics in high energy physics and in hadron physics. Similarities with the concept of thermofractal, recently introduded, are discussed, as well as comparison with experiments.

SICURA: il progetto LNF che ha vinto il bando della Regione Lazio per Progetti di Gruppi di ricerca Verrà presentato il progetto SICURA (SICUrezza RAdiologica), una proposta innovativa elaborata da Catalina Curceanu e da Roberto Bedogni che ha vinto il bando della Regione Lazio per Progetti di Gruppi di ricerca – Conoscenza e Cooperazione per un Nuovo Modello di Sviluppo. Gli elementi chiave del progetto, che si inserisce negli ambiti della sicurezza radiologica e lotta al terrorismo, sono l’impiego di sensori a basso costo e la loro integrazione mirata a rivelare simultaneamente radiazioni X, gamma e neutroni, per la realizzazione di una sonda portatile per operare nell’ambito dei controlli di sicurezza e di ordine pubblico. Grazie all’elevata capacità di interconnessione, con la sonda SICURA si potranno monitorare, in tempo reale, scenari come piazze, scuole, eventi sportivi, concerti o centri commerciali.. Il seminario illustrerà il layout preliminare del sistema di misura SICURA, le sue peculiarità rispetto a sistemi commercialmente disponibili, ed i requisiti a cui dovrà rispondere.

An overview on the current design status of the electron-ion collider project eRHIC, proposed at BNL, is presented.