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Vector meson's spin alignments in high energy reactions

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Science China(Physics,mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-Tang Liang Yu-Gang Ma Xin-Li Sheng Qun Wang Key laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

Study on UV Excitation Properties of Eu 3+ at S6 Site in Bulk and Nanocrystalline Cubic Y2O3

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Journal of Rare Earths 2004年第1期22卷 45-48页

作者：张家骅,贾明理,吕少哲,骆永石,任新光,王笑军 Key laboratory of Excited State processes Key laboratory of Excited State processes Key laboratory of Excited State processes Key laboratory of Excited State processes Key laboratory of Excited State processes Key laboratory of Excited State processes Changchun Institute of Optics Fine mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Changchun Institute of Optics Fine mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Changchun Institute of Optics Fine mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Changchun Institute of Optics Fine mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Changchun Institute of Optics Fine mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Changchun Institute of Optics Fine mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Department of Physics Georgia Southern University Statesboro GA 30460 USA

Increases of emission intensities for Eu 3+ at the S 6 site relative to that at the C 2 site were observed as UV excitation wavelength decreases from 300 nm to 200 nm in both bulk and nanocrystalline cubic Y 2O 3:Eu 3+. Decomposition of excitation spectra shows that the charge transfer band of Eu 3+ at the S 6 site lies in the high-energy side of that at the C 2 site, resulting in that the energy transfer from the host prefers to the S 6 site. Detailed emission and excitation spectral characteristics were analyzed and discussed. In addition, spectral red-shift were found in both charge transfer bands in nanocrystalline Y 2O 3:Eu 3+ compared to the bulk material. The number ratio of S 6 sites to C 2 sites is also smaller in nanocrystalline Y 2O 3:Eu 3+ than that in the bulk one.

关键词： charge transfer band UV excitation nano-phosphor rare earths

Optical Properties of a Novel Trivalent Erbium Ions Doped into Phosphate Glass

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Journal of Rare Earths 2003年第S1期21卷 65-67页

作者：张继森秦伟平张立国秦冠仕吴崇锋赵丹林海洋 Key laboratory of Excited State processes Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences

A novel Er (3+)-doped (ZnO)(P_2O_5)(B_2O_3) glass with excellent optical properties was prepared. The glasses were proved to have high stability by the investigation of the durability in boiling water. The properties of their spectra at about 1.5 μm change a lot with the concentrations of both Er (3+) and B_2O_3. Compared with Er (3+)-doped into the borate glass and the zinc phosphate glass,the glass prepared in our laboratory shows a larger quenching concentration and a much broader emission band at 1.54 μm.

关键词： optics Er3+-doped phosphate glass rare earths

A green-yellow emitting β-Sr_2SiO_4:Eu^(2+) phosphor for near ultraviolet chip white-light-emitting diode

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Journal of Rare Earths 2008年第3期26卷 421-424页

作者：孙晓园张家骅张霞骆永石王笑军 Key laboratory of Excited State processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

Sr2SiO4：xEu^2＋ phosphors were synthesized through the solid-state reaction technique. The crystal phase of Sr2SiO4：xEu^2＋ phosphor manipulated by Eu^2＋ concentration was studied. The phase transited from β to α＇ in Sr2SiO4：xEu^2＋ phosphor with increasing europium concentration. The single β phase was formed as x≤005 and changed α＇ phase when x〉0.01. The emission spectrum of the β-Sr2SiO4：Eu^2＋ phosphor consisted of a green-yellow broadband peaking at around 540 nm and a blue band at 470 nm under near ultraviolet excitation. The white LEDs by combining near ultraviolet chips with β-Sr2SiO4：Eu^2＋ phosphors were fabricated. The luminous efficiency （15.7lm/W） was higher than α＇-Sr2SiO4：Eu^2＋ phosphor white LED.

关键词： luminescence silicate light-emitting diode rare earths

GaN-based MSM photovoltaic ultraviolet detector structure modeling and its simulation

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Journal of Semiconductors 2011年第3期32卷 61-65页

作者：陈一仁宋航黎大兵孙晓娟李志明蒋红缪国庆 Key laboratory of Excited State processes Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences

Based on the principles of metal-semiconductor-metal Schottky barrier photodetectors（MSM-PD）, using the carrier rate equations,the circuit simulation model of a GaN-based MSM photovoltaic ultraviolet detector is constructed through an appropriately equivalent *** using the Pspice analytical function of Cadence soft on the model,the relationship between the photocurrent and the terminal voltage under different UV light powers is *** result shows that under the given UV power,the photocurrent increases and tends to become saturated gradually as the terminal voltage of the device increases,and that under different UV powers,the photocurrent increases with increasing incident *** the analysis of the relationship between the photocurrent and the terminal voltage under the different ratios of interdigital electrode space and width is carried out when the UV power is *** results show that when the ratio of interdigital electrode space and width（L/W） equals 1,the photocurrent tends to be at a maximum.

关键词： MSM structure simulation equivalent circuit ultraviolet detector

Infrared-to-Visible Frequency up-Conversion in Trivalent Erbium Ions Doped Fluoride Glasses (ZnF_2-Al_F3-PbF_2-LiF)

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Journal of Rare Earths 2003年第3期21卷 315-317页

作者：秦冠仕秦伟平黄世华吴长峰赵丹刘晃清 Changchun Institute of Optics Fine Mechanics and Physics Key Laboratory of Excited States Processes Chinese Academy of Sciences

High efficiency frequency up conversion in trivalent erbium ion doped new fluoride glass matrix (ZnF 2 AlF 3 PbF 2 LiF) was investigated. Under 950 nm laser diode excitation, the glasses gave very intense green, weak red and violet emissions. The up conversion mechanism is discussed. In addition, the infrared transmittance spectrum, the Raman spectrum and the lifetime of the trivalent erbium states in the samples were measured. The results illustrate the large potential of these new glasses for photonic applications.

关键词： optics fluoride glasses Er 3+ up conversion rare earths

Synthesis of colloidal LaF_3: 0.04Yb^(3+), 0.01Er^(3+) nanocrystals with green upconversion luminescence

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Journal of Rare Earths 2008年第1期26卷 40-43页

作者：王艳秦伟平张继森曹春燕张继双金叶 Key laboratory of Excited State processes Changchun Institute of OpticsFine Mechanics and Physics Chinese Academy of Sciences

A synthesis of LaF3：0.04Yb^3＋,0.01Er^3＋ nanocrystals with oleic acid as a capping ligand was presemed. The X-Ray Diffraction （XRD） pattern indicated that the power was a single hexagonal phase. Transmission Electron Microscopy （TEM） demonstrated that the average size of the nanocrystals was less than 10 nm, with a narrow size distribution. The nanocrystals were dispersible in nonpolar solvents and form a fully transparent colloidal solution, and the solution was stable for several months without any aggregates. The Yb^3＋-Er^3＋ codoped nanocrystal colloidal solution exhibited a bright green upconversion fluorescence under 980 nm excitation from a diode laser. The nanocrystals were potentially applicable in biolabeling and bioimaging.

关键词： upconversion luminescence colloidal LaF3:0.04Yb^3+,0.01Er^3+ nanocrystals rare earths

Site Selective Spectroscopy of Surfactant-Assembled Y_2O_3∶Eu Nanotubes

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Journal of Rare Earths 2003年第6期21卷 601-604页

作者：吴长锋秦伟平张继森秦冠仕赵丹 Key laboratory of Excited State processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

Y_2O_3∶Eu nanotubes were synthesized by a surfactant assembly mechanism. Under ultraviolet-light excitation, the nanotubes present luminescence properties different from that of Y_2O_3∶Eu nanoparticles. The peak position of the charge transfer band in excitation spectra varies with the monitoring emission peaks, while the emission spectra are dependent on the excitation wavelength. Laser selective spectroscopy was performed to distinguish the local symmetries of the Eu^(3+) ions in the nanotubes. The results of laser-selective excitation indicate that the emission centers near the surface of nanotube walls exhibit inhomogeneously broadened spectra without spectral structures while the two sites (site B and site C) inside the nanotube walls present resolved spectral structures. It is concluded by the number and peak positions of the spectral lines that the sites B and C possess different site symmetries.

关键词： optics luminescence Y_2O_3∶Eu nanotube rare earths

Investigation of Modification Effect of B_2O_3 Component on Optical Spectroscopy of Er^(3+) Doped Tellurite Glasses

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Journal of Rare Earths 2007年第1期25卷 31-35页

作者：杨艳民陈宝玖王成任国仲王晓君 laboratory of Excited State processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of SciencesChangchun 130033 ChinaGraduate School of Chinese Academy of SciencesBeijing 100039 China laboratory of Excited State processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of SciencesChangchun 130033 China

To investigate the modification effect of the B2O3 component on tellurite glass, a series of glasses with a composition of xB2O3-（80-x）TeO2-10ZnO-10Na20 （x = 0, 10, 20, 30, 40, 50, 60, 70, 80） and an additional amount of 0.5% Er2Os（in molar） were prepared. The refractive index, the absorption edge of the host, the J-O parameters of Er^3＋ , the fluorescent decay time, the bandwidth, and the quantum efficiency for the 4Ⅰ13/2→4Ⅰ15/2 transition were obtained theoretically and experimentally. These results indicated that the introduction of B2O3 modified the performance of the tellurite glass. For example, with increasing content of B2O3, the refractive index of the host decreases from 1.9 to 1.5, the absorption edge of the host shifted toward the blue regime, the intensity parameter Ω6 changed from 1.08 × 10^-20（for the pure tellurite glass） to 1.98 ×10^-20 cm^2（for the pure borate glass）, the bandwidth of the 4Ⅰ13/2→4Ⅰ15/2 transition increased, and the quantum efficiency of the 4Ⅰ13/2→4Ⅰ15/2 transition decreased.

关键词： Er^3+ glass J-O theory bandwidth host absorption band gap quantum efficiencv rare earths