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Tag Archives: Evento scientifico

Nanoscience and Nanotechnology

The 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 2016 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. We plan to submit selected papers, based on conference talks and related discussions, for publication on a dedicated issue of a peer reviewed international journal we are . There will be Invited Lecturers and selected talks from the call for papers below, as well as a poster session. CALL FOR CONTRIBUTIONS 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 (or federico.micciulla@lnf.infn.it antonino.cataldo@lnf.infn.it) by 31st July 2016, specifying whether it is meant for oral or poster presentation. Authors will be notified of the acceptance of their submission by 1st September 2016. POSTER SESSION We wish inform authors that a BEST POSTER PRICE will be won, provide by a sponsor of conference. Additional detailed information can be found in the web site: https://agenda.infn.it/conferenceDisplay.py?ovw=True&confId=11337, or by e-mailing: bellucci@lnf.infn.it federico.micciulla@lnf.infn.it antonino.cataldo@lnf.infn.it silvia.bistarelli@lnf.infn.it Registration – There is no fee for attendance, however registration is …

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Extended Higgs Sector in Supersymmetry

We investigate an extension of the MSSM containing a SU(2) Higgs triplet of zero hypercharge and a gauge singlet. We show that in this model the allowed data for the Higgs boson interaction eigenstates tend to group into separate blocks for SU(2) triplet, doublet and singlet. The triplet sector has two degenerate paired states, each pair composed of a mostly-triplet charged Higgs and a mostly-triplet scalar or pseudoscalar state. The mostly-doublet sector involves instead a SM-like Higgs of 125 GeV and extra mass-degenerate states, composed of a charged, a scalar and a pseudoscalar state. We analyze the exotic decay of the SM-like Higgs into two light (hidden) pseudoscalars, as well as decays into final states containing taus, muons and bottom quarks, and explore the parameter space at the LHC. We also investigate the phenomenology of triplet-Like charged Higgs-boson pairs, decaying into multilepton final states, in different phases of energy and luminosity of the LHC.

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Lower bounds for the energy density in quantum integrable models

The energy density is classically positive, a property that fails to be true in quantum theory. However, if it were indefinitely negative, it might produce macroscopic violations of the second law of Thermodynamics or allow the existence of exotic spacetimes configurations (such as wormholes, time machines and warp drives). Fortunately, lower bounds exist and have been proved for linear fields (free quantum field theory), with few results for interacting models of QFT. In a class of quantum integrable models, on the level of one-particle states, we prove the existence of lower bounds for local averages of the energy density, establishing a first result for QFTs with interaction.

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High-purity germanium detectors in the measurements of gamma emitting radionuclides in environmental samples – mathematical vs classical efficiency calibration

High resolution gamma-ray spectrometry is a nuclear analytical technique widely used for a determination of radionuclides in wide range of their activities in various kind of samples, from nuclear waste samples to the environmental samples and foodstuffs. For the quantitative determination this technique requires a determination of a detector efficiency with a high accuracy. In the Laboratory for radioecology of the Ruder Boskovic Institute in Zagreb, we are using Canberra’s high purity germanium detectors for this type of measurements. As the detector efficiency depends on an energy of emitted gamma rays, physical properties of materials and a sample geometry, calibration standards with same characteristics should be used for the efficiency calibration. However due to a large variety of the materials that have to be analysed, it is hard to obtain standard materials of the same characteristics. Therefore, the possibility to determine the detection efficiency in a mathematical way by detector and sample setup modeling can significantly facilitate the procedure. The description of detector and its peformances, together with the comparison of accuracy and precision of the radionuclide determination by using mathematical calibrations and classically source-based ones in the measurements of specific environmental samples will be presented. As Canberra has developed Laboratory SOurceless Calibration Software (LabSOCS) for this aim, spectrometry setup, consisting of the Canberra broad energy germanium detector (BEGe) with the original lead shielding and Genie 2000, LabSOCS/ISOCS softwares are used for the quantitative determination of low-level activities in few specific matrices such as honey samples and borosilicate filters. Honey …

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Probabilities and signalling in quantum field theory

We present an approach to computing probabilities in quantum field theory for a wide class of source-detector models. The approach works directly with probabilities and not with squared matrix elements, and the resulting probabilities can be written in terms of expectation values of nested commutators and anticommutators. We present results that help in the evaluation of these, including an expression for the vacuum expectation values of general nestings of commutators and anticommutators in scalar field theory. This approach allows one to see clearly how faster-than-light signalling is prevented, because it leads to a diagrammatic expansion in which the retarded propagator plays a prominent role. We illustrate the formalism using the simple case of the much-studied Fermi two-atom problem.

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Quality Assurance and radiation tolerance studies on double-sided silicon sensors of the CBM Silicon Tracking System.

The Silicon Tracking System (STS) is the main tracking detector of the upcoming fixed-target Compressed Baryonic Matter (CBM) experiment which aims to explore the phase diagram of the strongly interacting matter in a region of high net baryonic densities and moderate temperatures. The STS will be used for the reconstruction of tracks of charged particles and determination of their momenta. The system comprises 8 tracking stations located 30 cm downstream of the target. It will be mounted with approximately 1200 double-sided silicon microstrip sensors in three different sizes. A high level of radiation damage is expected to impact on the sensors. The maximum exposure of 1× 1014 in 1 MeV neutron equivalent will be reached after several years of running depending on the physics program. The Quality Assurance (QA) procedures for the STS sensors will be overviewed highlighting the automated QA testing procedure for a single strip defect identification. In addition to this, the radiation tolerance studies performed on STS sensor prototypes will be presented.

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Going beyond traditional parton showers: amplitude-level evolution

I will explain how traditional parton showers, as implemented in the major general purpose monte carlo codes, are fundamentally limited in their accuracy and how that situation can be improved via a new amplitude-level algorithm that includes, amongst other things, Coulomb gluon exchanges between incoming and outgoing partons. Coulomb gluons are responsible for the breaking of soft-collinear factorization and they are what generates the underlying event and diffraction.

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New perspectives in effective quantum gravity and cosmological perturbation theory

In this talk I will show how the general framework of effective quantum gravity proposed by Brunetti, Fredenhagen and myself can be used to study problems in quantum cosmology. This formulation allows to derive some known results in (first order) cosmological perturbation theory from first principles and it provides a robust tool for computing higher order corrections. Conceptually, it works as a test ground for new ideas concerning construction of gauge invariant observables in effective quantum gravity. The non-local character of these observables leads to new interesting combinatorial structures arising in renormalization.

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Condensed Matter and Critical Phenomena

The workshop aims at presenting recent results in the mathematical theory of critical phenomena and effective theories in condensed matter physics and statistical mechanics, including: scaling limits of discrete spin systems, percolation models and interacting random walks; effective dynamics and phase transitions in interacting quantum many body systems; disordered electrons and localization phenomena. Invited speakers include:  M. Aizenman, R. Bauerschmidt, D. Chelkak, G. Gallavotti, K. Gawedzki, V. Mastropietro, B. Nachtergaele, A. Pizzo,  M. Porta, B. Schlein,  A. Vichi, S. Warzel Organizers: A. Giuliani, V. Mastropietro, A. Pizzo    

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POSITRON SOURCES FOR FUTURE COLLIDERS

Except the radioactive sources, the positron sources are all based on photon materialization into electron-positron pairs in a target. After a rapid recall of the different methods to generate photons, underlining the corresponding photon characteristics , we shall concentrate on three kinds of radiation: bremsstrahlung in amorphous targets , channeling and coherent bremsstrahlung in oriented crystals. Applications to future linear e+e- and circular μ+ μ – colliders will be presented.

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