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## Nondecoupling supersymmetry and an Lμ − Lτ gauge boson at Belle-II

The presence of kinetic mixing is an essential feature of any model that augments the Standard Model gauge symmetry with an additional U(1) symmetry . We look at the signal process, e+e− → γZ′ → γ+E/ at Belle-II, which is an outcome of this ubiquitous feature. We propose that the γ+E/ signal at the Belle-II detector will be a smoking gun for supersymmetry (SUSY) in the presence of a gauged U(1)Lμ−Lτ symmetry. A striking consequence of breaking the enhanced symmetry appearing in the limit of degenerate (s)leptons is the nondecoupling of the radiative contribution of heavy charged sleptons to the γ − Z ′ kinetic mixing. We take into account the severe constraints on gauged U(1)Lμ−Lτ models by several low-energy observables (like the muon (g − 2), data from the CCFR and BaBar collaborations, etc.) and show that any significant excess in all but the highest photon energy bin would be an undeniable signature of such heavy scalar fields in SUSY coupling to the Z′ gauge boson. The number of signal events depends crucially on the logarithm of the ratio of stau to smuon mass in the presence of SUSY. In addition, the number is also inversely proportional to the e+ − e− collision energy, making a low-energy, high-luminosity collider like Belle-II an ideal testing ground for this channel. This process can probe large swathes of the slepton mass ratio vs the additional gauge coupling (gX ) parameter space. More importantly, it can explore the narrow slice of MZ′ − ...

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## MUSE General Meeting

2019 Annual General Meeting reviewing the activities supported by the MUSE project. MUSE is a EU funded project under the Horizon 2020 Research and Innovation program, Grant Agreement 690835. It coordinates the activities of about 70 researchers from various European research institutes (INFN, University College London, University of Liverpool, Helmholtz-Centrum Dresden-Rossendorf, Fermilab) and industries (PRISMA, CAEN, AdvanSid) for the participation to the experiments at the Muon Campus of the Fermi National Laboratory (FNAL), in USA. The meeting will be held at the Frascati National Laboratory of INFN.

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## Spectroscopic Studies of Antihydrogen

Cold atoms of antihydrogen promise a unique opportunity to study the properties of atomic antimatter, and via comparisons with its well-studied matter-counterpart, the possibility to test CPT invariance. This symmetry is conserved in local quantum field theories, so tests in varied systems provides the experimental validation of this framework. In order to probe matter-antimatter symmetry at the highest possible precision, it is essential that the anti-atoms be suspended in vacuum to allow for detailed interrogation via laser light or microwaves. The ALPHA experiment, running at the CERN antimatter factory, is now trapping sufficient numbers of antihydrogen atoms to enable these studies. The best measurements in hydrogen are of the 1S-2S transitions (precision 0.01 ppt, determining the Rydberg),   the ground state hyperfine interval (precision 1ppt ), and the 2S-2P Lamb shift.  The trap environment is particularly challenging for spectroscopy and requires adaptation of the usual AMO techniques. I will present our recent measurements of these transitions in antihydrogen, where we have recently reported  2 ppt precision 1S-2S  and 9 ppm precision  ground state hyperfine interval results. Our current measurements of the antihydrogen 1s-2p transitions and demonstration of laser cooling together with the improved  antiproton beams from  ELENA  promise excellent prospects for even higher precision results.

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## Strange Matter Workshop – Strangeness studies in Italy and Japan

The main aim of the “Strange Matter Workshop Strangeness studies in Italy and Japan” Workshop is to discuss the status of the experiments performed in Italy (DAFNE collider) and Japan (J-PARC) which are studying the strong interactions of strangene (loans and hyperons) particles with the nuclear matter at low-energies, in particular kaonic atoms and nuclei, as well as  hyperon-nuclei interactions. Implications in physics and astrophysics will be discussed, together with future plans. The Workshop is organized and supported by MAECI (Ministero degli Affari Esteri e della Cooperazione Internazionale), within the StrangeMatter project, and  by LNF-INFN. Organizers: Catalina Curceanu (LNF-INFN), Chair Raffaele Del Grande (LNF-INFN) Masahiko Iwasaki (RIKEN, Japan) Alessandro Scordo (LNF-INFN) Diana Sirghi (LNF-INFN) Magdalena Skurzok  (LNF-INFN)

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## Boron Neutron Capture Therapy: status and Novosibirsk solution

At present, Boron Neutron Capture Therapy (BNCT) is considered to be a promising method for the treatment of tumors. The report presents the basics of BNCT, its development stages, the state of development of accelerator neutron sources for BNCT clinics and describes in detail the Novosibirsk accelerator neutron source. This source is a state-of-the-art device comprised of i) the Vacuum Insulation Tandem Accelerator (VITA) – a new type of charged particle accelerator, ii) an advanced solid lithium target with superior resistance to blistering, and iii) a neutron Beam Shaping Assembly. At VITA characterized by a high acceleration rate of charged particles a stationary proton beam with an energy of 2.3MeV and a current of 9 mA, sufficient for therapy, was obtained. A neutron-producing target optimal for forming an epithermal neutron flux that meets the requirements of BNCT has been developed and experimentally studied. To confirm the required quality of the neutron beam, the effect of neutron radiation on cell cultures and laboratory animals was studied. In the near future, it is planned to prepare a “handmade” Novosibirsk source for conducting therapy and to implement BNCT in 2022. The Novosibirsk source became the prototype source being built for the clinic in Xiamen (China) – one of the first five BNCT clinics. In addition to being used in BNCT, the source was used to determine dangerous impurities in ceramics for ITER and is planned to be used for radiation testing of the optical fiber and photomultiplier for CERN. In the latter case, ...

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## Wave-function Collapse as a Resolution of a Tension between General Relativity and Quantum Theory

Conferenza a cura del Prof. Sir Roger Penrosem (Università di Oxford). Il talk sarà in lingua inglese, adatto ad un pubblico specialistico. Il 25 settembre 2019 il Prof. Sir Roger Penrose, dell’Università di Oxford, terrà una conferenza ai Laboratori Nazionali di Frascati, illustrando la sua visione circa le possibilità di risolvere la tensione tra relatività generale e meccanica quantistica. La conferenza, intitolata “Il collasso della funzione d’onda quale soluzione all’attrito tra Relatività Generale e Teoria Quantistica”, si terrà alle ore 16:15 presso l’Auditorium Bruno Touschek. Il talk è organizzato nell’ambito del workshop “Is Quantum Theory exact? From quantum foundations to quantum applications” che avrà luogo ai LNF tra il 23 e il 27 settembre 2019. Roger Penrose è autore d’importanti contributi alla fisica matematica della relatività generale e della cosmologia. Ha ricevuto numerosi premi e riconoscimenti, tra cui, nel 1988, il Premio Wolf per la fisica assieme a Stephen Hawking per i teoremi sulle singolarità di Penrose–Hawking, la Medaglia Dirac (1989) e la Medaglia Einstein (1990). Ingresso libero su prenotazione Maggiori dettagli relativi al workshop saranno disponibili alla pagina dedicata: https://agenda.infn.it/event/19468/

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## Is Quantum Theory exact? From quantum foundations to quantum applications

The main aim of the “Is Quantum Theory exact? From quantum foundations to quantum applications” Workshop is to discuss theoretical and experimental hot issues related to quantum physics, from foundational issues (such as connection between gravity and quantum physics, collapse models, spin-statistics) to quantum technologies, including new findings and ideas to investigate quantum effects in biological systems. The Workshop is supported by the Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Roma, by LNF-INFN and by the Foundational Questions Institute, FQXi. Organizers: Catalina Curceanu (LNF-INFN), Chair Pawel Moskal (Jagellionian University, Krakow, Poland) Johann Marton (SMI-Vienna, Austria) Alessandro Scordo (LNF-INFN) Magdalena Skurzok (LNF-INFN) Kristian Piscicchia (Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Roma and LNF-INFN)   http://www.mdpi.com/journal/entropy Media partner Entropy (ISSN 1099-4300, Impact Factor: 2.419) is an open access journal which maintains a rigorous and fast peer-review system with a median publication time of 44 days from submission to publication online. Since its launch in 1998, it has been fully covered by the leading indexing and abstracting services, including Scopus and SCIE (Web of Science), Google Scholar and MathSciNet. You are welcomed to visit the website http://www.mdpi.com/journal/entropy and to learn more about the journal.

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## A search for the A-prime particle at JLab and a proposal for a Very Asymmetric Collider.

A search was done by using electro-production of a heavy photon (A’) in electron scattering from W nuclei with following decay to an electron-positron pair. The experiment was performed at Hall A of Jefferson Lab using a 2.1 GeV beam and collected statistics for a search sensitivity of 0.1 ppm (relative to the coupling of an EM photon). Such a sensitivity is about 10 times better than known from currently published experiments for the A’ mass near 200 MeV. The experiment and preliminary analysis of the data quality will be presented. In the second part of this talk, I will discuss the search for A’ in an inverse reaction with a positron-electron annihilation which has an important advantage of being independent of the A’ decay. The experiment for the mass range above 70 MeV requires a novel experimental technique because typical colliders with cm energy below 500 MeV have insufficient luminosity. The concept of a Very Asymmetric Collider is based on a low energy electron beam accelerator and a high energy positron storage ring. Such a configuration allows us to boost the luminosity to the level of 10$^{34}$ 1/cm$^2$/s.

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## Logarithmic accuracy of parton showers

We formulate some first fundamental elements of an approach for assessing the logarithmic accuracy of parton-shower algorithms based on two broad criteria: their ability to reproduce the singularity structure of multi-parton matrix elements, and their ability to reproduce logarithmic resummation results. We illustrate our approach by considering properties of two transverse-momentum ordered final-state showers, examining features up to second order in the strong coupling. In particular we identify regions where they fail to reproduce the known singular limits of matrix elements. The characteristics of the shower that are responsible for this also affect the logarithmic resummation accuracies of the shower, both in terms of leading (double) logarithms at subleading colour number and next-to-leading (single) logarithms at leading colour number.

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