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Intra-cycle depolarization of ultraintense laser pulses focused by off-axis parabolic mirrors

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High Power Laser Science and Engineering 2018年第2期6卷 141-148页

作者： Luca Labate Gianluca Vantaggiato Leonida A.Gizzi Istituto Nazionale di Ottica Consiglio Nazionale delle Ricerche Istituto Nazionale di Fisica Nucleare Sezione di Pisa

A study of the structure of the electric and magnetic fields of ultraintense laser pulses focused by an off-axis parabolic mirror is reported. At first, a theoretical model is laid out, whose final equations integration allows the space and time structure of the fields to be retrieved. The model is then employed to investigate the field patterns at different times within the optical cycle, for off-axis parabola parameters normally employed in the context of ultraintense laser–plasma interaction experiments. The results show that nontrivial, complex electromagnetic field patterns are observed at the time at which the electric and magnetic fields are supposed to vanish. The importance of this effect is then studied for different laser polarizations, f numbers and off-axis angles.

关键词： laser-driven particle acceleration laser focusing off-axis parabolic mirrors ultrashort laser pulses

Measurement of strong phases, D-D mixing, and CP violation using quantum correlation at charm threshold

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Frontiers of physics 2016年第1期11卷 1-15页

作者： Matteo Rama Sezione di Pisa dell'Istituto Nazionale di Fisica Nucleate Pisa Italy

We review the measurements of the D decay strong-phase parameters based on quantum-correlated D^0D^-0 pairs produced in the e^＋e^→（3770） →D^0D^-0 process, and we discuss their role in the measurements of Cabibbo-Kobayashi-Maskawa angle 7 and D-/9 mixing. In addition, we present estimates of the size of quantum-correlated datasets necessary to support the 7 and charm mixing measurements conducted at the LHCb and Belle Ⅱ experiments. Finally, we review the methods for measuring the D-D^- mixing and cP violation parameters at a high-luminosity charm factory, giving sensitivity estimates.

关键词： quantum correlation charm mixing CP violation

τ BRANCHING FRACTIONS

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Chinese Physics C 2016年第10期40卷 640-644页

作者： S.Banerjee K.Hayes A.Lusiani University of Louisville Hillsdale College Scuola Normale Superiore and INFN sezione di Pisa

In order to make optimal use of the experimental data to determine the T branching fractions, their uncertainties, and their correlations, we perform a global minimum X2 fit using the measured values, their uncertainties, their statistical correlations, their dependencies on external parameters and common systematics, and the relations that hold between the branching fractions, including a unitarity constraint on the sum of all the exclusive τ decay branching fractions. Starting with this edition, we use a new fit procedure, which has been elaborated by the Tau Physics Group within the Heavy Flavour Averaging Group （HFAG） [1].

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Overview and specifications of laser and target areas at the Intense Laser Irradiation Laboratory

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High Power Laser Science and Engineering 2021年第1期9卷 94-102页

作者： Leonida A.Gizzi Luca Labate Federica Baffigi Fernando Brandi Giancarlo Bussolino Lorenzo Fulgentini Petra Köster Daniele Palla Intense Laser Irradiation Laboratory(ILIL) Istituto Nazionale di Ottica-Consiglio Nazionale delle Ricerche(INO-CNR)Sede Secondaria di Pisa56124 PisaItaly Istituto Nazionale di Fisica Nucleare(INFN) Sezione di Pisa56127 PisaItaly

We present the main features of the ultrashort, high-intensity laser installation at the Intense Laser Irradiation Laboratory(ILIL) including laser, beam transport and target area specifications. The laboratory was designed to host laser–target interaction experiments of more than 220 TW peak power, in flexible focusing configurations, with ultrarelativistic intensity on the target. Specifications have been established via dedicated optical diagnostic assemblies and commissioning interaction experiments. In this paper we give a summary of laser specifications available to users,including spatial, spectral and temporal contrast features. The layout of the experimental target areas is presented, with attention to the available configurations of laser focusing geometries and diagnostics. Finally, we discuss radiation protection measures and mechanical stability of the laser focal spot on the target.

关键词： high-intensity laser laser focusing laser–plasma acceleration laboratory pointing stability radiation shielding ultrashort pulse amplification

Optical diagnostics for density measurement in high-quality laser-plasma electron accelerators

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High Power Laser Science and Engineering 2019年第2期7卷 40-50页

作者： Fernando Brandi Leonida Antonio Gizzi Intense Laser Irradiation Laboratory(ILIL) Istituto Nazionale di Ottica-Consiglio Nazionale delle Ricerche(INO-CNR)Sede Secondaria di PisaVia Moruzzi156124PisaItaly Istituto Nazionale di Fisica Nucleare(INFN) Sezione di PisaLargo Bruno PontecorvoLargoBruno Pontecorvo356127PisaItaly

Implementation of laser-plasma-based acceleration stages in user-oriented facilities requires the definition and deployment of appropriate diagnostic methodologies to monitor and control the acceleration process.An overview is given here of optical diagnostics for density measurement in laser-plasma acceleration stages,with emphasis on wellestablished and easily implemented approaches.diagnostics for both neutral gas and free-electron number density are considered,highlighting real-time measurement capabilities.Optical interferometry,in its various configurations,from standard two-arm to more advanced common-path designs,is discussed,along with spectroscopic techniques such as Stark broadening and Raman scattering.A critical analysis of the diagnostics presented is given concerning their implementation in laser-plasma acceleration stages for the production of high-quality GeV electron bunches.

关键词： gas target interferometry laser-plasma laser wake-field acceleration Raman scattering Stark broadening

Mt.Etna volcano high-resolution topography:airborne LiDAR modelling validated by GPS data

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International Journal of digital Earth 2016年第7期9卷 710-732页

作者： Marina Bisson Claudia Spinetti Marco Neri Alessandro Bonforte Istituto Nazionale di Geofisica e Vulcanologia via della Faggiola 32PisaItaly Istituto Nazionale di Geofisica e Vulcanologia Centro Nazionale Terremotivia di Vigna MurataRomeItaly Istituto Nazionale di Geofisica e Vulcanologia Sezione di CataniaOsservatorio EtneoPiazza RomaCataniaItaly

High-resolution digital topography is essential for land management and planning in any type of territory as well as the reproduction of the Earth surface in a geocoded digital format that allows several digital Earth applications.In a volcanic environment,digital Elevation Models are a valid reference for multi-temporal analyses aimed to observe frequent changes of a volcano edifice and for the relative detailed morphological and structural analyses.For the first time,a DTM(digital Terrain Model)and a DSM(digital Surface Model)covering the entire Mt.Etna volcano(Italy)derived from the same airborne Light Detection and Ranging(LiDAR)are here presented.More than 250 million 3D LiDAR points have been processed to distinguish ground elements from natural and anthropic features.The end product is the highly accurate representation of Mt.Etna landscape(DSM)and ground topography(DTM)dated 2005.Both models have a high spatial resolution of 2 m and cover an area of 620 km2.The DTM has been validated by GPS ground control points.The vertical accuracy has been evaluated,resulting in a root-mean-square-error of±0.24 m.The DTM is available as electronic supplement and represents a valid support for various scientific studies.

关键词： Airborne LiDAR GPS DEM Mt.Etna

Quantal symmetries in the non-linear σ model with Maxwell and non-Abelian Chern-Simons terms

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Chinese Physics C 2010年第5期34卷 535-538页

作者：王珂姜云国霍秋红 Department of Applied Physics Beijing University of Technology Department of Physics University of Pisa INFN Sezione di PisaLargo Pontecorvo3.Ed.C56127 PisaItaly College of Materials Science and Engineering Beijing University of Technology

The quantal symmetry property of the CP1 nonlinear σ model with Maxwell non-Abelian ChernSimons terms in(2+1) dimension is studied.In the Coulomb gauge,the system is quantized by using the Faddeev-Senjanovic(FS) path-integral formalism.Based on the quantaum Noether theorem,the quantal conserved angular momentum is derived and the fractional spin at the quantum level in this system is presented.

关键词： non-linear sigma model non-Abelian Chern-Simons fractional spin

Some pathogenic characters of paratyphoid Salmonella enterica strains isolated from poultry

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1161-1166页

作者： Fabrizio Bertelloni Giovanni Tosi Paola Massi Laura Fiorentini Maria Parigi Domenico Cerri Valentina Virginia Ebani Department of Veterinary Science University of PisaViale Delle Piagge 256124 Pisa Italy Istituto Zooprofilattico Sperimentale Della Lombardia e Dell'Emilia Romagna Sezione Diagnostica di Forl(i)Via Don E. Servadei 3E/3F47122 Forl(i)(FC) Italy

Objective: To investigate some pathogenic characters of Salmonella enterica strains isolated from poultry.Methods: Twenty-three genetically distinct Salmonella enterica strains, of different serovars and pulsotype, were examined for virulence traits. Resistance to gastric acid environment was estimated by measuring the percentage of survived bacterial cells after exposure for 2 h to a synthetic gastric juice. Strains were analyzed with PCR for the presence of the following virulence genes: mgtC and rhu M located on SPI-3, sopB and pipB located on SPI-5, Salmonella virulence plasmid(spv)R(spvR), spvB and spvC located on Salmonella plasmid virulence and sodCI, sopE, and gipA located on prophage.Finally, resistance to 21 antibiotics was tested with Kirby–Bauer method.Results: A percentage of 82.60% of strains were resistant to gastric environment after induction and 60.87% of the strains exhibited constitutive resistance too. Nineteen different virulence profiles were detected. The phage related genes sodCI and sopE and the plasmid mediated operon spvR, spvB and spvC(spvRBC) were detected in 82.60%,47.82% and 52.17% of strains, respectively. Typhimurium and Enteritidis strains showed the highest number of virulence genes. Twenty-one different antibiotic resistance profiles were obtained and two isolates(Typhimurium and Enteritidis) resulted sensible to all the tested molecules. The ampicillin, streptomycin, sulfonamide and tetracycline resistance profile was detected in seven isolates(30.43%).Conclusion: Our results show that paratyphoid Salmonella strains with several characters of pathogenicity, that may be cause of severe pathology in animals and humans, are circulating among poultry.

关键词： Paratyphoid salmonellae Poultry Gastric acid resistance Virulence genes Antimicrobial resistance

Cosmogonic Speculations: Particle Creation from Energy Conservation in the Universe Evolution

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Journal of Modern Physics 2016年第11期7卷 1331-1344页

作者： Paolo Christillin dipartimento di Fisica Università di Pisa and I.N.F.N. Sezione di Pisa Pisa Italy

Information about the Universe from Hubble’s law is consistent with that coming from the evaluation of inertial forces, supporting the picture of a steady state expansion of a black hole Universe. Backed up also by the consideration of the black body self energy, the post big bang temperature decrease is consistent with particle creation if energy conservation applies at every scale. This process is shown to provide a gravitational repulsive force which can counterbalance gravitational attraction thus allowing the possibility of a steady non-inflationary expansion. That seems to provide an alternative coherent scheme for our picture of the Universe evolution, disposing of the cosmological term, of dark energy and of the bulk of dark matter.

关键词： Cosmogony Black Holes Particle Creation Self Energy Inertial Forces