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Two-flavor hybrid stars with the Dyson-Schwinger quark model

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Chinese Physics C 2017年第11期41卷 110-116页

作者：魏金标陈欢 H.-J.Schulze School of Mathematics and Physics China University of Geosciences infn Sezione di Catania Dipartimento di FisicaUniversitá di Catania

We study the properties of two-flavor quark matter in the Dyson-Schwinger model and investigate the possible consequences for hybrid neutron stars,with particular regard to the two-solar-mass *** find that with some extreme values of the model parameters,the mass fraction of two-flavor quark matter in heavy neutron stars can be as high as 30 percent and the possible energy release during the conversion from nucleonic neutron stars to hybrid stars can reach 1052 erg.

关键词： hybrid stars quark matter equation of state Dyson-Schwinger equations

Study of geometric parameters for the design of short intakes with fan modelling

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Chinese Journal of Aeronautics 2022年第11期35卷 18-32页

作者： Andrea MAGRINI Ernesto BENINI dipartimento di Ingegneria Industriale Universitá degli Studi di PadovaPadova 35131Italy

The flow over a short intake is characterised by a strong interaction with the fan, that can only be captured when the rotor blades are modelled in the numerical simulations. In this paper, we use a coupled methodology to derive indications about relevant geometric variables affecting the high-incidence operation of an ultra-high bypass ratio turbofan intake with a length-to-diameter ratio of 0.35. By reproducing the effect of the fan through a body force model, we carry out a parametric study of the influence of the contraction ratio and the scarf angle at take-off conditions for a grid of 28 different three-dimensional shapes. The analysis of the selected performance metrics distributions at three angles of attack of 16., 24., and 28. reveals that a contraction ratio higher than 1.20 is needed to avoid separation at high incidence. While for an attached inlet the best performance is found with a moderate scarf angle, in presence of a developed separation the distortion level reduces as the scarf decreases up to negative values. We discuss the correspondence between the distortion indexes and the flow field, highlighting the origin of the detachment for the different geometries, according to the operating condition, and analysing the fan operation in the most distorted case. Finally, we assess the influence of modelling the rotor in the simulations, showing that its suppression effect on the separation at a given incidence depends on the intake geometric features.

关键词： Body force method Coupled methods Fan/intake interaction Nacelle aerodynamics Short intake UHBPR

Competition between fusion-evaporation and multifragmentation in central collisions in ^(58)Ni+^(48)Ca at 25A MeV

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Nuclear Science and Techniques 2013年第5期24卷 82-88页

作者： FRANCALANZA L ABBONDANNO U AMORINI F BARLINI S BINI M BOUGAULT R BRUNO M CARdellA G CASINI G AGOSTINO M D' De FILIPPO V De SANCTIS J GERACI E GIUSSANI A GRAMEGNA F GUIOT B KRAVCHUK V La GUIDARA E LANZALONE G Le NEINDRE N MAIOLINO C MARINI P MORELLI L OLMI A PAGANO A PAPA M PIANTELLI S PIRRONE S POLITI G POGGI G PORTO F RUSSOTTO P RIZZO F VANNINI G VANNUCCI L infn Laboratori Nazionali del Sud-LNS Catania 95123Italy dipartimento di fisica Universitàdi Catania I-95129Italy infn Sezione di Trieste Trieste I-34127Italy dipartimento di fisica Universitàdi FirenzeINFN Sezione di Firenze 1-50139Italy LPC Caen IN2P3-CNRS/ENSICAEN and UniversitéF-14050 Caen cedex 5-140France dipartimento di fisica Universitàdi Bologna and INFN Sezione di Bologna 4-50121Italy infn Sezione di Catania I-95129 Italy infn Sezione di Firenze I-50139 Italy dipartimento di fisica Universitàdi Milano and INFN Sezione di Milano1-20126Italy infn Laboratori Nazionali di Legnaro 1-35020 Italy Centro Siciliano di fisica Nucleare e Struttura della Materia Catania 1-95129Italy universitàKore Enna 1-94100Italy

The experimental data concerning the58Ni+48Ca reaction at Elab(Ni)=25A MeV,collected by using the CHIMERA 4π device,have been analyzed in order to investigate the competition among different reaction mechanisms for central collisions in the Fermi energy *** a main criterion for centrality selection we have chosen the flow angle(flow) method,making an event-by-event analysis that considers the shape of events,as it is determined by the eigenvectors of the experimental kinetic-energy *** the selected central events(flow >60°) some global variables,good to characterize the pattern of central collisions have been *** main features of the reaction products were explored by using different constraints on some of the relevant observables,like mass and velocity distributions and their *** emphasis was devoted,for central collisions,to the competition between fusion-evaporation processes with subsequent identification of a heavy residue and a possible multifragmentation mechanism of a well defined(if any) transient nuclear *** evolution of the system and pre-equilibrium emission were taken into account by simulating the reactions in the framework of transport *** approaches have been envisaged(dynamical stochastic BNV calculations + sequential SIMON code,QMD,CoMD,etc.).Preliminary comparison of the experimental data with BNV calculations shows reasonable agreement with the assumption of sequential multifragmentation emission in the mass region of IMFs close to the heavy *** deviations from sequential processes were found for those IMFs in the region of masses intermediate between the mass of heavy residues and the mass of light *** simulations are in *** experimental analysis will be enriched also by information obtained inspecting the IMF-IMF correlation function,in order to elucidated the nature of space-time decay property of the emitting source associated with events having

关键词：多重碎裂中心碰撞蒸发过程 MeV 竞争熔合国际货币基金组织事件分析

The HEPD particle detector of the CSES satellite mission for investigating seismo-associated perturbations of the Van Allen belts

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Science China(Technological Sciences) 2018年第5期61卷 643-652页

作者： AMBROSI Giovanni BARTOCCI Simona BASARA Laurent BATTISTON Roberto BURGER William J. CARFORA Luca CASTELLINI Guido CIPOLLONE Piero CONTI Livio CONTIN Andrea DE DONATO Cinzia DE SANTIS Cristian FOLLEGA Francesco M. GUANDALINI Cristina IONICA Maria IUPPA Roberto LAURENTI Giuliano LAZZIZZERA Ignazio LOLLI Mauro MANEA Christian MARCELLI Laura MASCIANTONIO Giuseppe MERGE Matteo OSTERIA Giuseppe PACINI Lorenzo PALMA Francesco PALMONARI Federico PANICO Beatrice PATRIZII Laura PERFETTO Francesco PICOZZA Piergiorgio POZZATO Michele PUEL Matteo RASHEVSKAYA Irina RICCI Ester RICCI Marco RICCIARINI Sergio Bruno SCOTTI Valentina SOTGIU Alessando SPARVOLI Roberta SPATARO Bruno VITALE Vincenzo Istituto Nazionale di fisica Nucleare (infn) Sezione di Perugia Perugia 06123 Italy Uninettuno university Rome 00186 Italy Istituto Nazionale di fisica Nucleare (infn) Sezione di Roma Tor Vergata Rome 00133 Italy Istituto Nazionale di fisica Nucleare (infn) TIFPA Povo (TN) 38123 Italy dipartimento di fisica Universita di Trento Povo (TN) 38123 Italy dipartimento di fisica Universita di Roma Tor Vergata Rome 00133 Italy IFAC-CNR Sesto Fiorentino (FI) 50019 Italy dipartimento di fisica e Astronomia Universita di Bologna Bologna 40127 Italy Istituto Nazionale di fisica Nucleare (infn) Sezione di Bologna Bologna 40127 Italy Istituto Nazionale di fisica Nucleare (infn) Sezione di Napoli Naples 80126 Italy Istituto Nazionale di fisica Nucleare (infn) LNE Frascati (RM) 00044 Italy Agenzia Spaziale Italiana (ASI) SSDC Rome 00133 Italy

CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2^(nd), 2018 from the Jiuquan Satellite Launch Center(China).

关键词： earthquake seismic-precursors particle detector Van Allen belts magnetosphere ionosphere space weather cosmic rays

Characterisation of Photocathodes Based on Pb Thin Film Deposited by UV Pulsed Laser Ablation

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Journal of Materials Science & Technology 2014年第1期30卷 37-40页

作者： Francisco Gontad Antonella Lorusso Giancarlo Gatti Massimo Ferrario Laura Gioia Passione Luana Persano Nicola Lovergine Alessio Perrone Istituto Nazionale di fisica Nucleare e università del Salento università del Salento Dipartimento di Matematica e Fisica "E.De Giorgi" Laboratori Nazionali di Frascati Istituto Nazionale di Fisica Nucleare Center for Biomolecular Nanotechnologies Istituto Italiano di Tecnologia dipartimento di Ingegneria dell'Innovazione Università del Salento National Nanotechnology Laboratory(NNL)

This work deals with the deposition of lead （Pb） thin films by the UV pulsed laser ablation technique, for their further use as photocathode devices in superconducting radio frequency guns. Scanning electron microscopy and atomic force microscopy analyses were performed to study the morphological features of Pb thin films deposited on Si （100） and Nb substrates. The films showed a granular structure with a nearly fully covered surface only for that one deposited on Nb substrate. X-ray diffraction measurements indicate the growth of polycrystalline Pb thin films with a preferential orientation along （111） planes. Results of the photoemission performance of Pb thin film deposited on Nb substrate showed a very encouraging average value of quantum efficiency of 6 x 10-5 through a single-photon absorption process, promoting further studies in the realisation of Pb photocathodes by this technique.

关键词： Pulsed laser deposition Lead thin film Metallic photocathodes Quantum efficiency

羊八井50m^2RPC地毯性能研究YBJ-ARGO合作组(英文)

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高能物理与核物理 2001年第1期25卷 79-85页

作者：何会海 C.Bacci 包克智 F.Barone B.Bartoli P.Bernardini S.Bussino E. Calloni R. Cardarelli S.Catalanotti S.Cavaliere F.Cesaroni 查敏 P.Creti 单增罗布 B.D'Ettorre Piazzoli M.DeVincenzi T.diGirolamo G.diSciascio 冯振勇傅宇高晓宇庚庆喜郭宏伟何瑁黄庆 M.I 中国科学院高能物理研究所宇宙线和高能天体物理开放实验室 infn and dipartimento di fisica dell’ Universtià di Roma Tre 郑州大学物理系 infn and dipartimento di fisica dell'università di Napoli infn and dipartimento di fisica dell'università di Lecce infn and dipartimento di fisica dell’ Universtivà di Roma Tre infn and dipartimento di fisica dell'università di Napoli infn and dipartimento di fisica dell'università di Roma "Tor Verga" infn and dipartimento di fisica dell'università di Lecce 西藏大学数理系拉萨850000 西南交通大学物理系山东大学物理系云南大学物理系西藏大学数理系 Istituto di Cosmogeofisica del CNR and infn università della Basilicata infn and dipartimento di fisica dell'università di padova

利用羊八井５０ｍ２ＲＰＣ地毯（ＹＢＪ－ＡＲＧＯ实验原型）的测试数据对其性能进行了分析研究，包括原初粒子方位角分布、天顶角分布、地毯的角分辨、探测时间系统误差对方位角分布的正弦调制、探测时间系统误差的离线修正、几何不对... 详细信息

利用羊八井５０ｍ２ＲＰＣ地毯（ＹＢＪ－ＡＲＧＯ实验原型）的测试数据对其性能进行了分析研究，包括原初粒子方位角分布、天顶角分布、地毯的角分辨、探测时间系统误差对方位角分布的正弦调制、探测时间系统误差的离线修正、几何不对称的小型地毯探测器上原初粒子到达方向重建误差造成的方位角分布的不均匀性等．

关键词： γ射线天文广延大气簇射 RPC 小型地毯探测器

On the role of the uncertainty principle in superconductivity and superfluidity

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Chinese Physics B 2012年第7期21卷 125-131页

作者： Roberto Onofrio dipartimento di fisica e Astronomia"Galileo Galilei" Universitàdi PadovaVia Marzolo 8Padova 35131Italy ITAMP Harvard-Smithsonian Center for Astrophysics60 Garden StreetCambridgeMA 02138USA

We discuss the general interplay between the uncertainty principle and the onset of dissipationless transport phenomena such as superconductivity and superfluidity. We argue that these phenomena are possible because of the robustness of many-body quantum states with respect to the external environment, which is directly related to the uncertainty principle as applied to coordinates and momenta of the carriers. In the case of superconductors, this implies relationships between macroscopic quantities such as critical temperature and critical magnetic field, and microscopic quantities such as the amount of spatial squeezing of a Cooper pair and its correlation time. In the case of ultracold atomic Fermi gases, this should be paralleled by a connection between the critical temperature for the onset of superfluidity and the corresponding critical velocity. Tests of this conjecture are finally sketched with particular regard to the understanding of the behaviour of superconductors under external pressures or mesoscopic superconductors, and the possibility to mimic these effects in ultracold atomic Fermi gases using Feshbach resonances and atomic squeezed states.

关键词： superconductivity superfluidity uncertainty principle squeezed states

A Coupled FEM-BEM Approach for the Solution of the Free-Boundary Axi-Symmetric Plasma Equilibrium Problem

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Communications in Computational Physics 2022年第1期31卷 27-59页

作者： M.Bonotto D.Abate P.Bettini F.Villone Consorzio RFX(CNR ENEAINFNUniversitàdi PadovaAcciaierie Venete SpA)C.so Stati Uniti 435127 PadovaItaly infn-LNL LegnaroItaly dipartimento di Ingegneria Industriale(diI) Universitàdi PadovaItaly Consorzio CREATE DIETIUniversitàdi Napoli Federico IIItaly

In this paper we present a coupled Finite Element Method–Boundary Element Method(FEM-BEM)approach for the solution of the free-boundary axi-symmetric plasma equilibrium *** proposed method,obtained from an improvement of the Hagenow-Lackner coupling method,allows to efficiently model the equilibrium problem in unbounded domains by discretizing only the plasma region;the external conductors can be modelled either as 2D or 3D models,according to the problem of in*** paper explores different iterative methods for the solution of the nonlinear Grad-Shafranov equation,such as Picard,Newton-Raphson and Newton-Krylov,in order to provide a robust and reliable tool,able to handle large-scale problems(*** resolution equilibria).This method has been implemented in the FRIDA code(FReeboundary Integro-differential Axisimmetric–https://***/matteobonotto/FRIDA),together with a suitable Adaptive Integration Technique(AIT)for the computation of the source *** has been successfully tested and validated against experimental data from RFX-mod device,and numerical equilibria of an ITER-like device.

关键词： FEM-BEM MHD plasma equilibrium Grad-Shafranov equation

Energy spectrum of cosmic protons and helium nuclei by a hybrid measurement at 4300 m a.s.l.

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Chinese Physics C 2014年第4期38卷 25-31页

作者： B.Bartoli P.Bernardini 毕效军 I.Bolognino P.Branchini A.Budano A.K.Calabrese Melcarne P.Camarri 曹臻 R.Cardarelli S.Catalanotti 陈松战陈天禄 P.Creti 崔树旺戴木忠 A.D'Amone 单增罗布 I.De Mitri B.D'Ettorre Piazzoli T.di Girolamo G.di Sciascio 冯存峰冯朝阳冯振勇苟全补郭义庆何会海胡海兵胡红波 M.Iacovacci R.Iuppa 贾焕玉拉巴次仁厉海金 G.Liguori 刘成刘俊刘茂元卢红马玲玲马欣华 G.Mancarella S.M.Mari G.Marsella D.Martello S.Mastroianni P.Montini C.C.Ning M.Panareo B.Panico L.Perrone P.Pistilli F.Ruggieri P.Salvini R.Santonico S.N.Sbano 沈培若盛向东石峰 A.Surdo 谭有恒 P.Vallania S.Vernetto C.Vigorito 王辉吴超勇吴含荣薛良杨群羽杨先楚姚志国袁爱芳查敏张慧敏张力张学尧张勇赵静扎西次仁扎西桑珠周勋秀祝凤荣朱清棋 G.Zizzi 白云翔陈明君陈垚冯少辉高博顾旻皓侯超李晓晓刘佳刘加丽王旭肖刚张丙开张寿山周斌左雄 dipartimento di fisica dell’università di Napoli "Federico II" Complesso Universitario di Monte Sant’Angelovia Cinthia Istituto Nazionale di fisica Nucleare Sezione di Napoli Complesso Universitario di Monte Sant’Angelovia Cinthia dipartimento di Matematica e fisica "Ennio De Giorgi" Università del Salento via per Arnesano Istituto Nazionale di fisica Nucleare Sezione di Lecce via per Arnesano Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences dipartimento di fisica dell’università di Pavia via Bassi 627100 Pavia Italy Istituto Nazionale di fisica Nucleare Sezione di Pavia via Bassi 627100 Pavia Italy Istituto Nazionale di fisica Nucleare Sezione di Roma Tre via della Vasca Navale 8400146 Roma Italy Istituto Nazionale di fisica Nucleare-CNAF Viale Berti-Pichat 6/240127 Bologna Italy dipartimento di fisica dell’università di Roma "Tor Vergata" via della Ricerca Scientifica Istituto Nazionale di fisica Nucleare Sezione di Roma Tor Vergata via della Ricerca Scientifica Tibet university Hebei Normal university Yunnan university Shandong university Southwest Jiaotong university dipartimento di fisica dell’università "Roma Tre" via della Vasca Navale 8400146 Roma Italy Osservatorio Astrofisico di Torino dell’Istituto Nazionale di Astrofisica via P.Giuria 110125 Torino Italy Istituto Nazionale di fisica Nucleare Sezione di Torino via P.Giuria 110125 Torino Italy dipartimento di fisica dell’università di Torino via P.Giuria 110125 Torino Italy Physics Department Kunming University Normal College of Fuyang

The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured below the so-called ＂knee＂ by using a hybrid experiment with a wide field-of-view Cherenkov telescope and the Resistive Plate Chamber （RPC） array of the ARGO-YBJ experiment at 4300 m above sea level. The Hydrogen and Helium nuclei have been well separated from other cosmic ray components by using a multi-parameter technique. A highly uniform energy resolution of about 25% is achieved throughout the whole energy range （100-700 TeV）. The observed energy spectrum is compatible with a single power law with index γ=-2.63±0.06.

关键词： Cherenkov telescope ARGO-YBJ energy spectrum hybrid measurement composition