# Tag Archives: Evento scientifico

## Highlights in Supergravity:Callan-Coleman-Jackiw 47 years later

We discuss properties of the supercurrent in the superconformal formulation of N=1,4D supergravity. Superconformal matter gives simplified conservation laws as in the case of the CCJ improved energy momentum tensor. This approach is useful to classify curved superspace backgrounds.

Scopri di più »## Measuring propagation speed of Coulomb fields

In planetary systems, the problem arises whether gravity attracting the planets towards the central star has an instantaneous action or propagates with finite velocity. Laplace noticed that, if gravity propagated with finite velocity, planets motion would become unstable due to a torque originating from time lag of the gravitational interactions. Given that equations describing gravitational interaction are formally the same describing electrostatic interactions, we have performed an experiment meant to measure the time/space evolution of the electric field generated by a uniformly moving set of electrons. The results we obtain seem compatible with an electric field rigidly carried by the beam itself.

Scopri di più »## A GENERALIZED SPIN STATISTICS THEOREM

The spin statistics theorem is generalized to show that a state obeys Fermi-Dirac statistics if and only if the state is invariant under the action of SL(n;C). Also a discussion of the experimental evidence and how the theorem relates to spin entanglement and special relativity will be presented.

Scopri di più »## Atomic structure of highly charged ions and exotic atoms: from accurate tests of Quantum Electrodynamics to the measurement of unstable particles masses.

An overview of investigations on unusual atomic systems, such highly charged ions and pionic atoms, is presented. In highly charged ions, where the associated Coulomb field is several order of magnitude higher that of the most powerful available laser, Quantum Electrodynamics (QED) corrections, as the self-energy and the vacuum polarisation, have to be considered to all order of Zα. This is still a challenge for theoretical predictions, which can finely tested by spectroscopy of such systems. In pionic hydrogen and deuterium, high-accuracy X-ray spectroscopy provides important information on the strong interaction force between the pion (formed by an anti-quark and a quark) and the nucleons (proton and/or the neutron, each formed by three quarks). Experimental findings are compared to the more accurate available predictions based on effective field theories. In the case of atomic transitions where the influence of the strong force is negligible and QED predictions are well known, accurate X-ray spectroscopy is used to determine the mass of the negatively charged pion. The new measurement presented here yields an accuracy of 1.3 parts per million improving the accuracy of the value recommended by the Particle Data Group by a factor of about two.

Scopri di più »## EBS Project Overview

The ESRF – the European Synchrotron Radiation Facility – is a user facility in Grenoble, France, and the source of the most intense high-energy (6 GeV) X-rays in the world. It was the very first ‘third-generation’ synchrotron to be built and its light provides opportunities for scientists all over the world in the exploration of materials and living matter ranging from the chemistry and physics of materials to archaeology and cultural heritage, together with structural biology and medical applications, the sciences of the environment and the sciences of information and nanotechnologies. In 2019, the existing storage ring will be removed and a first-of-a-kind new lattice, based on an innovative arrangement of magnets, will be installed in its place, dramatically reducing the equilibrium emittance. This ‘fourth-generation’ synchrotron will produce an X-ray beam 100 times more brilliant and coherent than the ESRF source today, allowing imaging down from the micrometre to the nanometre scale and ‒ in parallel with upgraded beamlines, instrumentation and data infrastructure ‒ providing previously unimaginable opportunities for applications as varied as nanoscopy, science at extreme conditions and structural biology. The ESRF ‒ Extremely Brilliant Source (EBS) project was launched in 2015 and its current status, two years into the project, will be presented, alongside the expected performance of the accelerator, the technical challenges confronted and its future potential fields of applications.

Scopri di più »## Bandi MAECI

Seminario informativo sulle opportunità offerte dai Bandi del MAECI (Ministero degli Affari Esteri e della Cooperazione Internazionale) interverrà la Cons. A.Pastorelli (Direzione Generale per la Promozione del Sistema Paese – MAECI)

Scopri di più »## Autumn Institute: Precision physics to achieve the LHC accuracy goals

Aim of the workshop: The Large Hadron Collider has so far performed extremely well and led in 2012 to the milestone discovery of the Higgs boson; however, no signal of new physics has shown up yet. For the sake of carrying out searches for physics Beyond the Standard Model and reliable estimates of the backgrounds, precise calculations and Monte Carlo generators have been of paramount importance. In this mini-workshop, we shall present novel improvements in the matching of parton showers with exact NLO matrix elements, as well as progresses in the fits of parton distribution functions, including small-x resummation. New strategies to measure the top-quark mass and CP violation in top events at the LHC will also be presented. Speakers: Benjamin Fuks (Université Pierre et Marie Curie, Paris) "Next-to-leading order calculations matched to parton showers for supersymmetry and dark matter" Umberto De Sanctis (Università di Roma `Tor Vergata') "Top physics with soft muons in ATLAS" Marco Bonvini (Università di Roma `La Sapienza') "Small-x resummation in PDF fits"

Scopri di più »## Nanoscience and Nanotechnology

Nanoscience and Nanotechnology 2017 ISTITUTO NAZIONALE DI FISICA NUCLEARE LABORATORI NAZIONALI DI FRASCATI Frascati, Via Enrico Fermi, 40 16 – 20 OCTOBER 2017 The NEXT Nanotechnology group at INFN – LNF organizes since 2000 a series of international meetings in the area of nanotechnology. The Nanotechnology group at INFN – LNF organizes since 2000 a series of international meetings in the area of nanotechnology. The conference in 2017 is devoted to recent developments in nanoscience and its manifold technological applications. It consists of a number of tutorial/keynote lectures, as well as research talks presenting frontier nanoscience research developments and innovative nanotechnologies in the areas of biology, medicine, aerospace, optoelectronics, energy, materials and characterizations, low-dimensional nanostructures and devices. There will be Invited Lecturers and selected talks from the ad-hoc call for papers, as well as a poster session. Authors wishing to submit their work for presentation at the conference can send an abstract as a doc file (max 2 pages, including figures) to bellucci@lnf.infn.it by 21st September 2017, specifying whether it is meant for oral or poster presentation. Authors will be notified of the acceptance of their submission by 25th September 2017. Registration – There is no fee for attendance, however registration is mandatory and must be submitted before 30th September 2017. Hotel reservation is the responsibility of the participants. Additional information can be found in the web site: http://www.lnf.infn.it/lnfadmin/travel/alberghi.html Information how to reach the venue is found in: http://www.lnf.infn.it/lnfadmin/travel/travel.html A map of the Frascati town, ...

Scopri di più »## The Quest for the Axion

The axion arises in the course of an elegant solution of the strong CP problem. In addition, it is a very good candidate for dark matter and may explain the excessive cooling of stars in various stages of their evolution. Moreover, the saxion may play the role of the inflaton, leading to a very predictive and distinctive cosmological history of the universe. There are new, relatively small experiments around the globe, which are hunting the axion and complement the search for physics beyond the Standard Model at the Large Hadron Collider.

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