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Tag Archives: Evento scientifico

Recent progress in understanding deconfinement and chiral symmetry breaking transitions

While the crucial role of gauge topology was recognized from 1970’s, confinement was associated with monopoles and chiral symmetry breaking with instantons. Recognizing presence of non-zero holonomy, van Baal and others discovered splitting of the instantons into their constituents — the instanton-dyons. Several groups now work out properties of their ensembles, which generate both the deconfinement and chiral phase transitions in QCD-like theories. Introducing variable phases for quark periodicity conditions — known as flavor holonomies — one can switch fermion coupling to different dyons, and thus dramatically change both the order and temperature of both transitions. First lattice studies of modified — so called $Z_N$-symmetric QCD — have also found these effects.

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LISA Pathfinder, first step to observing gravitational waves from space

Observation of gravitational waves (g.w.) in the mHz region is extremely promising for the wealth of sources and processes that can be studied. That frequency region is only accessible from space, and that is the motivation of the ESA mission eLISA, scheduled for the mid 2030’s. We will report, fresh after disclosure, on the first results of the space experiment LISA Pathfinder, a feasibility demonstrator, flying now and performing tests of free fall and related technologies.

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What is Time?

“If nobody ask me what is time I think I know, but if somebody ask me I don’t know what to say” (Sant`Agostino). Still now “time is the most mysterious quantity of Physics” (Greenberger). I do think that the description of time evolution in ALL fundamental equation of physics is inadequate. In this seminar I will explain why and I will outline a possible solution for this fundamental problem, which gives also a precise meaning to the time-energy uncertainty relation and generalizes the Caldirola “cronon” concept eliminating the self-acceleration solutions of the equation of motion of a free electron.

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LNF Mini-Workshop Series: Development of novel detectors at LNF

The Frascati Laboratories have a long and outstanding expertise in detectors development  and  construction. Through the years these detectors have been successfully installed on many apparatus,in Frascati and in others High Energy and Nuclear Physics Laboratories. In this workshop some of the most recent novel technologies developed at LNF will be reported by our youngest colleagues: these technologies are suitable not only for general purpose collider detectors and dark matter searches, but also for astrophysics, medical and industrial applications.

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The physics of Binary Neutron Star merger from general relativistic numerical simulations.

In this talk I will focus on the physics of Binary Neutron Stars merger obtained from numerical simulations of the Einstein equations coupled to matter. The results are obtained using a semi-realistic descriptions of the equation of state (EOS), where the EOS is described by a seven-segment piece-wise polytropic and a thermal component. One of the important characteristics of the present investigation is that it is entirely performed using only publicly available open source software, the Einstein Toolkit for the dynamical evolution and the LORENE code for the generation of the initial models. After the gravitational-wave event GW150914, observed by the LIGO/Virgo collaboration, the new eve of Gravitational Wave physics has just began and it is clear that accurate modelling of the gravitational wave signal emitted by compact binary sources will play a prominent role. In particular I will present results for the gravitational wave-signal obtained from three-dimensional numerical simulations of the dynamics of binary neutron star (BNS) mergers from the late stage of the inspiral process up to about 20 ms after the system has merged, either to form a hyper-massive neutron star (NS) or a rotating black hole (BH).

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Strangeness, Gravitational waves and neutron stars

ONE DAY MEETING Strangeness, Gravitational waves and neutron stars 10 June 2016 INFN-LNF Aula di Direzione (Ed. 1)   The meeting is centred on the most recent developments and findings in the strangeness physics, in particular the possible role of strangeness in neutron stars, on the discovery of gravitational waves and on the future of these fields, considering that a copious source of gravitational waves are expected to be the binaries of neutron stars. Combining the theoretical and experimental findings in these sectors will allow a better and more accurate understanding of the involved processes, at the crossroad between strong interaction and general relativity. Organizers: Catalina Oana Curceanu, Maria Paola Lombardo Speakers include: Omar Benhar (INFN Sapienza), Ignazio Bombaci (Univ. e INFN Pisa), Alessandro Drago (Univ. e INFN Ferrara, Italy) Viviana Fafone (ToV), Alessandra Feo (Univ. Perugia), Massimo Mannarelli (LNGS), Kristian Piscicchia (LNF-INFN e Centro Fermi, Roma), Jacobus Verbaarschot (SUNY),  

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A short walk through the physics of neutron stars

Neutron stars are excellent observatories to test our present understanding of the theory of strong interacting matter at extreme conditions, and they offer an interesting interplay between nuclear processes and astrophysical observables. Conditions of matter inside neutron stars are very different from those one can find in Earth and, therefore, a good knowledge of the equation of state of dense matter is required to understand the properties of neutron stars. On the first part of this talk I will briefly review some of the general properties of these fascinating objects. On the second part, I will revise the problem of the strong softening of the EoS, and the consequent reduction of the maximum mass, induced by the presence of hyperons in the neutron star interior, a puzzle which has become more intringuing and difficult to solve due the recent measurements of the unusually high masses of the millisecond pulsars PSR J1903+0327 ($1.667\pm 0.021 M_\odot$), PSR J1614-2230 ($1.97 \pm 0.04 M_\odot$), and PSR J0348+0432 ($2.01 pm 0.04 M_\odot$). Finally, I will also examine the role of hyperons on the cooling properties of newly born neutron stars and on the so-called r-mode instability.

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Mathematics and Physics at the Crossroads

Mathematicians and theoretical physicists meet and discuss outstanding issues and future research directions at the crossroads of Gauge Fields, Strings and Holography Operator Algebras and Quantum Field Theory Condensed Matter and Critical Phenomena an INdAM intensive  period  framed within the cooperation agreement between CMTP and INFN The program runs from June 6 to July 29 and from August 22 until September 30, 2016. Its purpose is to bring together leading international experts and talented young researchers in mathematics and theoretical physics, especially in Algebra, Operator Algebras, Geometry, Statistical Mechanics, Quantum Field Theory and String Theory, in order to stimulate interaction and cross-fertilization between these disciplines.  The format includes seminars, informal meetings and three topical workshops on Operator Algebras and Quantum Field Theory, Gauge and String Theory, Condensed Matter and Critical Phenomena.  A Mathematical Physics school is planned as well. Office space, meeting rooms and access to the LNF Library will be provided. We welcome the participation of students and young postdocs.                                       October 7, 2016 Beyond the Crossroads…    The program has concluded, and thanks to anyone who has helped making it a success! One-day concluding event will take  place at INdAM on October 27    

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Una possibile partecipazione INFN al progetto Qubic

L’esperimento Qubic si propone la misura dei modi B di polarizzazione con una sensibilità sul parametro r (rapporto tra l’ampiezza delle perturbazioni tensoriali/scalari) pari a circa 2×10-2 in tre anni di presa dati. Si tratta di un passo ulteriore nel miglioramento dell’attuale limite di Bicep2+Planck (r

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The Horizon2020 EuPRAXIA Project – Towards a Groundbreaking European Plasma Accelerator

Particle accelerators based on RF systems have been a remarkable success story since they were proposed 90 years ago by Ising and demonstrated experimentally by Wideröe. Today there are some 30,000 accelerators world-wide, from small industrial accelerators to the Large Hadron Collider, one of mankind largest machines. The maximum beam energy in particle accelerators has for many years followed an exponential increase with time, the so-called Livingston curve. However, progress has slowed down significantly over the last years. At the same time the new technology of plasma-based electron accelerators has emerged with exponential progress since 1980. Acceleration lengths are a factor 100-1000 shorter than in conventional accelerators. Plasmas excited by industrially available lasers have produced accelerating gradients of up to 100 GV/m and electrons at energies up to 4.25 GeV, promising a revolution in the way accelerators are built. Much more compact and cost-effective accelerators can be imagined. The potential of this technology is discussed. National and international activities are summarized. Special emphasis will be placed on the “European Plasma Research Accelerator with Excellence in Applications” (EuPRAXIA) project, the second accelerator-related EU design study in Horizon2020. This EU-financed study aims at proposing a European Research Infrastructure that pioneers a compact plasma accelerator for applications in photon science, High Energy Physics and other fields, like medical imaging applications. EuPRAXIA is supported by a consortium of 16 member institutes and presently 15 associated partner labs in Europe, Asia and the US.

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