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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 domain.As 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 tensor.For the selected central events(flow >60°) some global variables,good to characterize the pattern of central collisions have been constructed.The 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 correlations.Much 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 system.Dynamical evolution of the system and pre-equilibrium emission were taken into account by simulating the reactions in the framework of transport theories.different 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 residues.Possible 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 IMFs.Further simulations are in progress.The 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 the largest IMF multiplicity.

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

68Ni和132Sn矮共振约束对称能密度依赖行为(英文)

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IMP & HIRFL Annual Report 2010年 23-25页

作者：曹李刚 Andrea Carbone Gianluca Colo dipartimento di Fisica Universit`a degliStudi di Milano infn Sezione di Milano

The energy per particle in a nuclear system characterized by a total density ρ(sum of the neutron and proton densities ρn and ρp),and by a local asymmetry δ≡(ρn-ρp)/ρ,is usually written asEA(ρ,δ)=E/A(ρ,δ=0)+ S(ρ)δ2.(1)Odd powers of δ are forbidden by the isospin symmetry and the term proportional to δ4 is found to be negligible.The above equation defines the so-called symmetry energy S(ρ).Determining the values of the symmetry energy at various densities

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1-13 Constraints on Symmetry Energy from Pygmy Resonances in 68Ni and 132Sn

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IMP & HIRFL Annual Report 2010年第1期 23-25页

作者： Cao Ligang Andrea Carbone Gianluca Colo dipartimento di Fisica Universit＇a degliStudi di Milano via Celoria 16 20133 Milano Italy infn Sezione di Milano via Celoria 16 20133 Milano Italy

Primordial black hole mass functions as a probe of cosmic origin

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： Yi-Fu Cai Chengfeng Tang Geyu Mo Sheng-Feng Yan Chao Chen Xiao-Han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(infn) Sezione di MilanoMilano 20146Italy diSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati infn Via Enrico Fermi 541 Frascati(Roma)00044Italy infn sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce cosmology.The standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from PBHs.We demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic origin.Additionally,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

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双J/ψ介子不变质量谱中首次发现新型结构

Science Bulletin 2020年第23期65卷 1983-1993,M0004页

作者：大型强子对撞机底夸克实验(LHCb)合作组 Nikhef National Institute for Subatomic Physics Netherlands Amsterdam Physik-Institut Universitat Zurich Switzerland Zurich Oliver Lodge Laboratory University of Liverpool United Kingdom Liverpool Instituto Galego de Fisica de Altas Enerxias (IGFAE) Universidade de Santiago de Compostela Spain Santiago de Compostela H.H. Wills Physics Laboratory University of Bristol United Kingdom Bristol Universite Clermont Auvergne CNRS/IN2P3LPC France Clermont-Ferrand University of Michigan United States Ann Arbor INFN Sezione di Milano Italy Milano University of Cincinnati United States Cincinnati Fakultat Physik Technische Universitat Dortmund Germany Dortmund European Organization for Nuclear Research (CERN) Switzerland Geneva School of Physics and Astronomy University of Glasgow United Kingdom Glasgow ICCUB Universitat de Barcelona Spain Barcelona Department of Physics and Astronomy University of Manchester United Kingdom Manchester Petersburg Nuclear Physics Institute NRC Kurchatov Institute (PNPI NRC KI) Russia Gatchina Universidade Federal do Rio de Janeiro (UFRJ) Brazil Rio de Janeiro Universite Paris-Saclay CNRS/IN2P3IJCLab France Orsay infn sezione di Firenze Italy Firenze Institute of Physics Ecole Polytechnique Federale de Lausanne (EPFL) Switzerland Lausanne infn sezione di Ferrara Italy Ferrara Physikalisches Institut Ruprecht-Karls-Universitat Heidelberg Germany Heidelberg Institute for High Energy Physics NRC Kurchatov Institute (IHEP NRC KI) ProtvinoRussia Russia Protvino Syracuse University United States Syracuse Yandex School of Data Analysis Russia Moscow Aix Marseille Univ CNRS/IN2P3CPPM France Marseille Department of Physics University of Warwick United Kingdom Coventry Imperial College London United Kingdom London Laboratoire Leprince-Ringuet France Palaiseau Centro Brasileiro de Pesquisas Fisicas (CBPF) Brazil Rio de Janeiro infn sezione di Genova Italy Genova Universita di Genova Italy Genova National University of Science and Technolog

除介子和重子之外的由夸克和胶子组成的粒子统称奇异强子.对奇异强子的研究可以加深对强相互作用的理解.利用质心能量为7、8和13 TeV,总积分亮度为9 fb-1的质子-质子对撞数据,大型强子对撞机底夸克实验(LHCb)研究了双J/ψ介子的不变质... 详细信息

除介子和重子之外的由夸克和胶子组成的粒子统称奇异强子.对奇异强子的研究可以加深对强相互作用的理解.利用质心能量为7、8和13 TeV,总积分亮度为9 fb-1的质子-质子对撞数据,大型强子对撞机底夸克实验(LHCb)研究了双J/ψ介子的不变质量分布.实验在6.9 GeV/c2附近观测到一个符合共振态谱形的窄峰(X(6900))并在两倍于J/ψ介子质量(≈6.2 GeV/c2)以上看到一个较宽的凸起结构.在超过5倍标准偏差的显著水平上,实验数据排除了6.2到7.4 GeV/c2的质量范围内不含任何共振态的假设,这个质量范围涵盖了理论模型预言的由四个粲夸克组成的强子态的质量.基于X(6900)结构的不变质量分布呈现Breit-Wigner谱形的假设,实验对它的质量和自然宽度进行了测量.此次发现将有助于理解强子内部的强相互作用机制,进而推动量子色动力学的理论研究.

关键词：量子色动力学大型强子对撞机强相互作用强子显著水平共振态质量范围粲夸克

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中子的内部结构:来自BESIII的研究

Science Bulletin 2022年第6期67卷 557-560页

作者： Simone Pacetti Rinaldo Baldini Ferroli Andrea Bianconi Egle Tomasi-Gustafsson dipartimento di Fisica e Geologia and INFN Sezione di Perugia1-06123 PerugiaItaly Laboratori Nazionali di Frascati dell'infn 1-00044 FrascatiItaly dipartimento di Ingegneria dell'Informazione Brescia1-25133 BresciaItaly INFN Sezione di Pavia1-27100 PaviaItaly DPhN IRFUCEAUniversitéParis-Saclay1-91191 Gif-sur-Yvette CedexFrance

The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these data represent an unprecedented tool for highlighting and studying specific features of the neutron FF.Until a few years ago,the only available data were those obtained by the FENICE experiment at Frascati,in the’90s[2].

关键词： BESⅢ precise

CPT INVARIANCE TESTS IN NEUTRAL KAON DECAY

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Chinese Physics C 2016年第10期40卷 707-709页

作者： M. Antonelli LNF-infn, Frascati LNF-infn Frascati infn sezione di Napoli

CPT theorem is based on three assumptions： quantum field theory, locality, and Lorentz invariance, and thus it is a fundamental probe of our basic understanding of particle physics. Strangeness oscillation in K^0 -K^... 详细信息

关键词： CPT定理介子衰变 Lorentz 中性测试变性量子场论粒子物理

Search for the doubly heavy baryons Ωbc~0 and Ξbc~0 decaying to Λc~+π~- and Ξc~+π~-

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Chinese Physics C 2021年第9期45卷 14-25页

作者： R.Aaij C.Abellán Beteta T.Ackernley B.Adeva M.Adinolfi H.Afsharnia C.A.Aidala S.Aiola Z.Ajaltouni S.Akar J.Albrecht F.Alessio M.Alexander A.Alfonso Albero Z.Aliouche G.Alkhazov P.Alvarez Cartelle S.Amato Y.Amhis L.An L.Anderlini A.Andreianov M.Andreotti F.Archilli A.Artamonov M.Artuso K.Arzymatov E.Aslanides M.Atzeni B.Audurier S.Bachmann M.Bachmayer J.J.Back P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista Leite R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Baryshnikov J.M.Basels G.Bassi B.Batsukh A.Battig A.Bay M.Becker F.Bedeschi I.Bediaga A.Beiter V.Belavin S.Belin V.Bellee K.Belous I.Belov I.Belyaev G.Bencivenni E.Ben-Haim A.Berezhnoy *** D.Berninghoff H.C.Bernstein C.Bertella A.Bertolin C.Betancourt F.Betti Ia.Bezshyiko S.Bhasin J.Bhom L.Bian M.S.Bieker S.Bifani P.Billoir M.Birch F.C.R.Bishop A.Bitadze A.Bizzeti M.Bj?rn M.P.Blago T.Blake F.Blanc S.Blusk D.Bobulska J.A.Boelhauve O.Boente Garcia T.Boettcher A.Boldyrev A.Bondar N.Bondar S.Borghi M.Borisyak M.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boyer C.Bozzi M.J.Bradley S.Braun A.Brea Rodriguez M.Brodski J.Brodzicka A.Brossa Gonzalo D.Brundu A.Buonaura C.Burr A.Bursche A.Butkevich J.S.Butter J.Buytaert W.Byczynski S.Cadeddu H.Cai R.Calabrese L.Calefice L.Calero diaz S.Cali R.Calladine M.Calvi M.Calvo Gomez P.Camargo Magalhaes A.Camboni P.Campana A.F.Campoverde Quezada S.Capelli L.Capriotti A.Carbone G.Carboni R.Cardinale A.Cardini I.Carli P.Carniti L.Carus K.Carvalho Akiba A.Casais Vidal G.Casse M.Cattaneo G.Cavallero S.Celani J.Cerasoli A.J.Chadwick M.G.Chapman M.Charles Ph.Charpentier G.Chatzikonstantinidis C.A.Chavez Barajas M.Chefdeville C.Chen S.Chen A.Chernov V.Chobanova S.Cholak M.Chrzaszcz A.Chubykin V.Chulikov P.Ciambrone M.F.Cicala X.Cid Vidal G.Ciezarek P.E.L.Clarke M.Clemencic H.V.Cliff J.Closier J.L.Cobbledick V.Coco J.A.B.Coelho J.Cogan E.Cogneras L.Cojocariu P.Collins T.Colombo L.Congedo A.Contu N.Cooke G.Coombs G.Corti C.M.Costa Sobral B.Couturier D.C.Craik J.Crkovská M.Cruz Torres R.Currie C.L.Da Silva E.Dall’Occo J.Dalseno C.D’Amb AGH-University of Science and Technology Faculty of Computer Science Electronics and Telecommunications AGH-University of Science and Technology Faculty of Physics and Applied Computer Science Aix Marseille Univ CNRS/IN2P3 CPPM Budker Institute of Nuclear Physics (SB RAS) Cavendish Laboratory University of Cambridge Center for High Energy Physics Tsinghua University Centro Brasileiro de Pesquisas Físicas (CBPF) DS4DS La Salle Universitat Ramon Llull Departamento de Fisica Universidad Nacional de Colombia Department of Physics and Astronomy University of Manchester Department of Physics and Astronomy Uppsala University Department of Physics University of Oxford Department of Physics University of Warwick European Organization for Nuclear Research (CERN) Fakult?t Physik Technische Universit?t Dortmund Guangdong Provencial Key Laboratory of Nuclear Science Institute of Quantum Matter South China Normal University H.H. Wills Physics Laboratory University of Bristol Hangzhou Institute for Advanced Study UCAS Hanoi University of Science Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences Horia Hulubei National Institute of Physics and Nuclear Engineering I.Physikalisches Institut RWTH Aachen University ICCUB Universitat de Barcelona infn Laboratori Nazionali di Frascati infn sezione di Bari infn sezione di Bologna infn sezione di Cagliari infn sezione di Ferrara infn sezione di Firenze infn sezione di Genova INFN Sezione di Milano INFN Sezione di Milano-Bicocca infn sezione di Perugia infn sezione di Pisa infn sezione di Roma La Sapienza infn sezione di Roma Tor Vergata Imperial College London Institut für Physik Universit?t Rostock Institute Of High Energy Physics (IHEP) Institute for High Energy Physics NRC Kurchatov Institute (IHEP NRC KI) Institute for Nuclear Research of the National Academy of Sciences (KINR) Institute for Nuclear Research of the Russian Academy of Sciences (INR RAS) Institute of Nuclear Physics Moscow State University (SINP MSU) Institute of Part

The first search for the doubly heavy Ωbc~0 baryon and a search for the Ξbc~0 baryon are performed using pp collision data collected via the LHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 TeV,corresponding to an integrated luminosity of 5.2 fb-1.The baryons are reconstructed via their decays to ∧c~+π~-andΞc~+π~-.No significant excess is found for invariant masses between 6700 and 7300 MeV/c2,in a rapidity range from2.0 to 4.5 and a transverse momentum range from 2 to 20 MeV/c.Upper limits are set on the ratio of the Ωbc~0 andΞbc~0 production cross-section times the branching fraction to ∧c~+π~-(Ξc~+π~-) relative to that of the ∧b~0(Ξb~0) baryon,for different lifetime hypotheses,at 95% confidence level.The upper limits range from 0.5×10-4to 2.5×10-4for theΩbc~0→∧c~+π~-(Ξbc~0→∧c~+π~-) decay,and from 1.4×10-3to 6.9×10-3for the Ωbc~0→Ξc~+π~-(Ξbc~0→Ξc~+π~-) decay,depending on the considered mass and lifetime of the Ωbc~0(Ξbc~0) baryon.

关键词： B physics quarkonium spectroscopy heavy quark production

Effect of the Tensor Force on Charge-Exchange Spin-Dependent Multipole Excitations

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Chinese Physics Letters 2010年第10期27卷 60-63页

作者：白春林张焕乔张锡珍许甫荣 H. Sagawa G. Colo China Institute of Atomic Energy Beijing 102413 School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 Center for Mathematics and Physics University of Aizu Aizu- Wakamatsu Fukushima 965-8560 Japan dipartimento di Fisica Universitgdegli Studi di Milano and INFN Sezione di Milano 20133 Milano Italy

The charge-exchange spin-dipole （SD） and spin-quadrupole （SQ） strength functions of 90Zr are calculated with and without the tensor terms of the Skyrme interaction in self-consistent HF＋RPA approach. It is found that, in SD and SQ transitions, the RPA correlations associated with the tensor terms shin dramatically the strengths of （Ylσ）λ = l？1 and （Ylσ）λ = 1 modes upward and downward, respectively, and also shift the strengths of （Ylσ）λ = l ＋ 1 modes upward. The coupling between （Yl = λ ？ 1σ）λ and （Yl = λ ＋ 1σ）λ modes arising from the tensor correlation is noticeable. The RPA tensor correlations produce strengths of SD and SQ modes, which are distributed in a much wider energy range, and the （Ylσ）λ = l ？ 1 modes dominate the high energy part of the strength functions. These energy shifts and coupling effects of different modes can be understood qualitatively by expressing a finite range tensor force in a separable form.

关键词：自旋相关张量 Skyrme相互作用激励多极收费能量范围耦合效应