检索结果-南通市图书馆

Energy Transfer in Cubic PbF_(2):Gd Crystals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2001年第6期18卷 829-830页

作者： ZHANG Guo-Bin SHI Jun-Yan ZHANG Zeng-Ming HAN Zheng-Fu SHI Chao-Shu ZHANG Xin-Yi G.Zimmerer M.Kirm SHEN Ding-Zhong National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026 Department of Astronomy and Applied Physics University of Science and Technology of ChinaHefei 230026 II institut für experimental physik der Universität hamburg 22607 HamburgGermany Shanghai institute of Ceramic Chinese Academy of SciencesShanghai 200050

The emission and excitation spectra of cubic PbF_(2):Gd were *** with pure crystals,the emissions from Gd^(3+) were observed upon cation exciton excitation in lattices,while the emission from intrinsic self-trapped ex... 详细信息

关键词： excitation cubic pure

Temperature Dependence of the Luminescence Decay Time of a PbWO_(4) Scintillator

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1998年第6期15卷 455-456页

作者： SHI Chao-shu DENG Jie HAN Zheng-fu XIE Zhi-jian LIAO Jing-ying G.Zimmerer J.Beker M.Kamada M.Runne A.Schröder Department of Physics University of Science and Technology of ChinaHefei 230026 NSRL University of Science and Technology of ChinaHefei 230026 Shanghai institute of Ceramics Chinese Academy of SciencesShanghai 200050 II.institut für experimental physik der Universität hamburg Germany UVSOR Institute of Molecular ScienceJapan

experimental results are given for the temperature dependence of the decay time of the emission at 430nm from PbWO_(4) crystal under vacuum-ultraviolet(82nm)photon excitation in the temperature range of *** structures in the curve are interpreted for the first time by studying the thermoluminescence of PbWO_(4),which originates from the traps in the crystal.

关键词： crystal ultraviolet excitation

Formation of Superheavy Nuclei in Massive Fusion Reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

原子核物理评论 2009年第S1期26卷 168-174页

作者： Scheid Werner institut fr Theoretische physik der Universitt

Within the concept of the dinuclear system(DNS),by incorporating the coupling of the relative motion to the nucleon transfer process,a dynamical model is proposed for describing the formation of superheavy residue nucleus in massive fusion reactions,in which the capture of two heavy colliding nuclei,the formation of compound nucleus and the de-excitation process are calculated using empirical coupled channel model,solving master equation numerically and statistical theory,respectively. By using the DNS model,the evaporation-residue excitation functions in the 48Ca induced fusion reactions and in the cold fusion reactions are investigated systematically and compared with available experimental data. Optimal evaporation channels and combinations as well as the corresponding excitation energies are proposed. The possible factors that influencing the isotopic dependence of the production cross sections are analyzed. The formation of the superheavy nuclei based on the isotopes U with different projectiles are also investigated.

关键词： DNS model massive fusion reaction evaporation-residue excitation function

Dust growth in protoplanetary disks-a comprehensive experimental / theoretical approach

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2010年第12期10卷 1199-1214页

作者： Jürgen Blum institut für Geophysik und extraterrestrische physik University of Braunschweig

More than a decade of dedicated experimental work on the collisional physics of protoplanetary dust has brought us to a point at which the growth of dust aggregates can - for the first time - be self-consistently and reliably modeled. In this article, the emergent collision model for protoplanetery dust aggregates, as well as the numerical model for the evolution of dust aggregates in protoplanetary disks, is reviewed. It turns out that, after a brief period of rapid collisional growth of fluffy dust aggregates to sizes of a few centimeters, the protoplanetary dust particles are subject to bouncing collisions, in which their porosity is considerably decreased. The model results also show that low-velocity fragmentation can reduce the final mass of the dust aggregates but that it does not trigger a new growth mode as discussed previously. According to the current stage of our model, the direct formation of kilometer-sized planetesimals by collisional sticking seems unlikely, implying that collective effects, such as the streaming instability and the gravitational instability in dust-enhanced regions of the protoplanetary disk, are the best candidates for the processes leading to planetesimals.

关键词： planetary systems: protoplanetary disks -- planetary systems: formation-- methods: laboratory -- methods: numerical

Production mechanism of superheavy nuclei in massive fusion reactions

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2009年第S1期33卷 86-88页

作者：冯兆庆靳根明李君清 Werner Scheid institute of Modern Physics Chinese Academy of Sciences institut für Theoretische physik der Universitt

Within the concept of the dinuclear system (DNS), a dynamical model is proposed for describing the formation of superheavy nuclei in complete fusion reactions by incorporating the coupling of the relative motion to the nucleon transfer process. The capture of two heavy colliding nuclei, the formation of the compound nucleus and the de-excitation process are calculated by using an empirical coupled channel model, solving a set of microscopically derived master equations numerically and applying statistical theory, respectively. Fusion-fission reactions and evaporation residue excitation functions of synthesizing superheavy nuclei (SHN) are investigated systematically and compared them with available experimental data. The possible factors that affecting the production cross sections of SHN are discussed in this workshop.

关键词： DNS model master equations production cross sections

Λb^0-baryon production in pp collisions in the general-mass variable-flavour-number scheme,and comparison with CMS and LHCb data

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2018年第8期42卷 34-44页

作者： G.Kramer H.Spiesberger II.institut für Theoretische physik Universitat HamburgLuruper Chaussee 149D-22761 HamburgGermany institut für physik Johannes-Gutenberg-UniversitatStaudinger Weg 7D-55099 MainzGermany Centre for Theoretical and Mathematical Physics and Department of Physics University of Cape TownRondebosch 7700South Africa

We calculate the next-to-leading-order cross section for the inclusive production ofΛ（b ）baryons in pp collisions in the general-mass variable-flavor-number *** use realistic evolved non-perturbative fragmentation functions obtained from fits to B-meson production in e^＋e^-annihilation and compare our results for transversemomentum and rapidity distributions with recent experimental data from the CMS and the LHCb collaborations at the CERN *** find satisfactory agreement in general,with some indication for the need to modify the available fragmentation functions at larger values of the scale variable.

关键词： heavy flavor production perturbative QCD Ab production

A new quantum speed-meter interferometer: measuring speed to search for intermediate mass black holes

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2018年第1期7卷 940-948页

作者： Stefan L.Danilishin Eugene Knyazev Nikita V.Voronchev Farid Ya.Khalili Christian Gräf Sebastian Steinlechner Jan-Simon Hennig Stefan Hild institut für Theoretische physik Leibniz Universität Hannover and Max-Planck-Institut für Gravitationsphysik(Albert-Einstein-Institut)Callinstraße 38D-30167 HannoverGermany SUPA School of Physics and AstronomyUniversity of GlasgowGlasgow G128QQUnited Kingdom M.V.Lomonosov Moscow State university Faculty of PhysicsMoscow 119991Russia institut für Laserphysik und Zentrum für Optische Quantentechnologien der Universität hamburg Luruper Chaussee 14922761 HamburgGermany

The recent discovery of gravitational waves(GW)by Advanced LIGO(Laser Interferometric Gravitational-wave Observatory)has impressively launched the novel field of gravitational astronomy and allowed us to glimpse exciting objects about which we could previously only *** sensitivity improvements at the low-frequency end of the detection band of future GW observatories must rely on quantum non-demolition(QND)methods to suppress fundamental quantum fluctuations of the light fields used to readout the GW *** we present a novel concept of how to turn a conventional Michelson interferometer into a QND speed-meter interferometer with coherently suppressed quantum back-action *** use two orthogonal polarizations of light and an optical circulator to couple *** carry out a detailed analysis of how imperfections and optical loss influence the achievable *** find that the proposed configuration significantly enhances the low-frequency sensitivity and increases the observable event rate of binary black-hole coalescences in the range of 102103Mby a factor of up to~300.

关键词： quantum allowed coherent

Next-to-leading-order relativistic and QCD corrections to prompt J/ψpair photoproduction at future e^(+)e^(−)colliders

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第8期48卷 104-112页

作者： Zhi-Guo He Xiao-Bo Jin Bernd A.Kniehl Rong Li Department of Physics and Electronics School of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing 100029China II.institut für Theoretische physik Universität HamburgLuruper Chaussee 14922761 HamburgGermany institut für Theoretische physik Universität Regensburg93040 RegensburgGermany Center of Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China institute of Theoretical Physics Xi’an Jiaotong UniversityXi’an 710049China

Within the framework of nonrelativistic-QCD factorization,we calculate both the next-to-leading-order relativistic and QCD corrections to prompt J/ψpair production,with feed-down fromψ(2S)mesons,via photon-photon collisions at future e^(+)e^(−)colliders,including the Future Circular Lepton Collider(FCC-ee),the Circular Electron Positron Collider(CEPC),and the Compact Linear Collider(CLIC).We present total cross sections and distributions in single J/ψtransverse momentum and rapidity,as well as in J/ψpair invariant *** relativistic and QCD corrections both turn out to be large and ***,the production rates are large enough for useful experimental studies.

关键词： heavy quarkonium perturbative calculation two-photon collisions

Dibaryons: Molecular versus compact hexaquarks

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2021年第2期45卷 23-38页

作者： H.Clement T.Skorodko physikalisches institut der Universität Tübingen and Kepler Center for Astro and Particle Physics University of TübingenAuf der Morgenstelle 14D-72076 TübingenGermany

Hexaquarks constitute a natural extension of complex quark systems,just as tetra-and pentaquarks *** this end,the current status of d^(*)(2380)in both experiment and theory is *** high-precision meas-urements in the nucleon-nucleon channel and analyses thereof have established d^(*)(2380)as an indisputable reson-ance in the long-sought dibaryon *** features of this I(J^(P))=0(3^(+))state are its narrow width and deep binding relative to the 0(1232)0(1232)*** decay branchings favor theoretical calculations predict-ing a compact hexaquark nature of this *** review the current status of experimental and theoretical studies on d^(*)(2380)as well as new physics aspects it may bring in *** addition,we review the situation at the 0(1232)N and N^(*)(1440)N thresholds,where evidence for a number of resonances of presumably molecular nature has been found-similar to the situation in charmed and beauty ***,we briefly discuss the situation of dibaryon searches in the flavored quark sectors.

关键词： dibaryon hexaquark molecule