25MeV/u ~(40)Ar+~(115)In,~(58)Ni,~(27)Al反应中前中角区碎片角分布和元素Z分布

测量了 ２５ＭｅＶ／ｕ４０　Ａｒ＋１１５　Ｉｎ，５８　Ｎｉ，２７　Ａ１反应前中角区出射碎片的角分布和 元素 Ｚ分布．用改进的量子分子动力学（ＭＱＭＤ）模型研究了碎片的角分布和 Ｚ 分布．理论计算值和实验值整体上符合得很好，但在前角区，ＭＱＭＤ模型低估 了碎片的产额，在中角区对于Ｚ接近弹核的碎片，理论计算值比实验值偏高．碎 片产物的角分布和Ｚ分布还与统计蒸发模型ＧＥＭＩＮＩ进行了比较，结果表明，在 前角区平衡蒸发成份所占的比例很小，中角区所占的比例有所增加，但仍然是较 小的比例．同时发现平衡蒸发成份随着出射碎片核电荷数Ｚ的减小而逐渐减 少．

Sputtering induced by highly charged Pb-208(q+) bombardment on Al surface

Highly charged ions (HCls) carrying high Coulomb potential energy (E-p) could cause great changes in the physical and chemical properties of material surface when they bombard on the solid surface. In our work, the secondary ion yield dependence on highly charged Pbq+ (q = 4-36) bombardment on Al surface has been investigated. Aluminum films (99.99%) covered with a natural oxide film was chosen as our target and the kinetic energy (E-k) was varied between 80 keV and 400 keV. The yield with different incident angles could be described well by the equation developed by us. The equation consists of two parts due to the kinetic sputtering and potential sputtering. The physical interpretations of the coefficients in the said equation are discussed. Also the results on the kinetic sputtering produced by the nuclear energy loss on target Surface are presented.

Cross-correlation of excitation functions for different fragments and different scattering angles in Al-27(F-19, x)y reactions

Excitation functions have been measured for different projectile-like fragments produced in Al-27(F-19,x)y reactions at incident energies from 110.25 to 118.75 MeV in 250 keV steps. Strong cross section fluctuations of the excitation functions are observed. The cross- correlation coefficients of the excitation functions for different atomic number Z and for different scattering angle theta(cm) have been deduced. These coefficients are much larger than the statistical theoretical calculated ones. This indicates that there are strong correlations between different exit channels in the dissipative heavy ion Collision of Al-27(F-19,x)y.

Studies on the exotic structure of Al-23

The longitudinal momentum distribution (P-//) of fragments after one-proton removal from Al-23 and reaction cross sections (sigma(R)) for Al-23,Al-24 on carbon target at 74A MeV have been measured simultaneously. An enhancement in sigma(R) is observed for Al-23 compaxed with Al-24. The full width at half maximum of the P-// distribution for Mg-22 fragments has been determined to be 232 +/- 28 MeV/c. Analysis of P-// using the Few-Body Glauber Model indicates a dominant d-wave configuration for the valence proton in the ground state of Al-23. The exotic structure in Al-23 is discussed.

The coulomb potential energy effect on the intensity of the characteristic lines at highly charged ion incendence on Al surface

The Al atomic characteristic spectral lines were induced by the impact of Ar-40(q+) ions (8 <= q <= 16; kinetic energy 150 keV) on Al surface. The result shows that by Penning impinging and resonant capture, the ion energy is deposited on the Al surface to excite the target atom, which is different from light excitation. Not only are the transitions betweem electronic configurations of the atomic complex excited, but the enhancing tendency of the characteristic spectral line intensity is consistent with the enhancing tendency of the coulomb potential energy of the incident ions with increasing charged states.

Largely deformed dinuclear system formed in F-19+Al-27 dissipative collision

Excitation functions are measured for different charge products of the F-19+(27) Al reaction in the laboratory energy range 110.25-118.75MeV in steps of 250keV at theta(lab) = 57 degrees, 31 degrees and -29 degrees. The coherence rotation angular velocities of the intermediate dinuclear systems formed in the reaction are extracted from the cross section energy autocorrelation functions. Compared the angular velocity extracted from the experimental data with the ones deduced from the sticking limit, it is indicated that a larger deformation of the intermediate dinuclear system exists.

Rotation and deformation of the dinuclear system formed in dissipative reaction of F-19+Al-27

Excitation functions of the reaction products B, C, N, O, F and Ne emitted from the dissipative reaction of (19) F+(27) Al have been measured at incident energies from 110.25MeV to 118.75MeV in steps of 250keV. The moments of inertia of the intermediate dinuclear system formed in the reaction are extracted from the energy autocorrelation functions of the products. Comparing the moment of inertia extracted from the experimental data with the calculated one by using the sticking limit, it indicates that the formed dinuclear system has a large deformation in the reaction process.

Melting of Au and Al in nanometer Fe/Au and Fe/Al multilayers under swift heavy ions: A thermal spike study

Knowing that Fe is sensitive to swift heavy ion irradiations whereas Au and Al are not, the behavior of nanometric metallic multilayer systems, like [Fe(3 nm)/Au(x)](y) and [Fe(3 nm)/Al(x)](y) with x ranging between 1 and 10 mn, were studied within the inelastic thermal spike model. In addition to the usual cylindrical geometry of energy dissipation perpendicular to the ion projectile direction, the heat transport along the ion path was implemented in the electronic and atomic sub-systems. The simulations were performed using three different values of linear energy transfer corresponding to 3 MeV/u of Pb-208, Xe-132 and Kr-84 ions. For the Fe/Au system, evidence of appearance of a molten phase was found in the entire Au layer, provided the Au thickness is less than 7 nm and 3 nm for Pb and Xe ions, respectively. For the Fe/Al(x) system irradiated with Pb ions, the Al layers with a thickness less than 4 nm melt along the entire ion track. Surprisingly, the Fe layer does not melt if the Al thickness is larger than 2 nm, although the deposited energy surpasses the electronic stopping power threshold of track formation in Fe. For Kr ions melting does not occur in any of the multilayer systems.

Non-reproducibility of the cross sections of the products induced from dissipative reaction of F-19+Al-27

The differential cross sections of the dissipative products B, Q N, O, F, Ne, Na and Mg induced from the reactions of F-19+Al-27 at two incident energies have been measured at the HI-13 tandem accelerator, Beijing. In the case of a fixed beam incident energy 114MeV or 118.75MeV respectively, identical reaction system and the same detection system, 20 target points in steps of 2mm on(.)a 10mmx50mm rectangular Al foil have been bombarded. The experimental results indicate that the probability distribution of the cross sections is much wider than a standard Gaussian distribution. This non-reproducibility of the cross sections can't be interpreted by the statistical property of a finite count rate.

基于激光诱导击穿光谱技术的铝合金成分定量分析；Quantitative analysis of element concentration in Al alloy by using laser-induced breakdown spectroscopy

利用Nd:YAG激光器输出的532nm激光束对位于空气中的标准变形铝合金样品进行烧蚀产生了激光诱导等离子体.对测量的230—440nm波长范围的光谱进行了谱线标定,同时基于自由定标方法对样品成分进行了定量分析,确定了样品中的元素含量.分析结果与标准值具有较好的一致性.

Quantitative analysis analysis of element concentration in Al alloy by using laser-induced breakdown spectroscopy

Laser-induced breakdown plasma is produced by using Q-switched Nd: YAG laser operating at 532 nm, which interacts with the Al alloy sample target in air. The spectral lines in the 230-440 nm wavelength range have been identified, and based on the calibration-free method, the mass concentration of Al alloy are obtained, which is in good agreement with the standard value of the sample.

Measurement of K*(892)(0) and K-0 mesons in Al plus Al collisions at 1.9A GeV

A new measurement of subthreshold K*(892)(0) and K-0 production is presented. The experimental data complete the measurement of strange particles produced in Al + Al collisions at 1.9A GeV measured with the FOPI detector at SIS at GSI (Darmstadt). The K*(892)(0)/K-0 yield ratio is found to be 0.0315 +/- 0.006(stat.) +/- 0.012(syst.) and is in good agreement with the transport model prediction. These measurements provide information on the in-medium cross section of K+-pi(-) fusion, which is the dominant process in subthreshold K*(892)(0) production.

Effect of substrate and annealing on the structural and optical properties of ZnO:Al films

ZnO:Al thin films with c-axis preferred orientation were deposited on glass and Si substrates using RF magnetron sputtering technique. The effect of substrate on the structural and optical properties of ZnO:Al films were investigated. The results showed a strong blue peak from glass-substrate ZnO:Al film whose intensity became weak when deposited on Si substrate. However, the full width at half maxima (FWHM) of the Si-substrate ZnO:Al (0 0 2) peaks decreased evidently and the grain size increased. Finally, we discussed the influence of annealing temperature on the structural and optical properties of Si-substrate ZnO:Al films. After annealing, the crystal quality of Si-substrate ZnO:Al thin films was markedly improved and the intensity of blue peak (similar to 445 nm) increased noticeably. This observation may indicate that the visible emission properties of the ZnO:Al films are dependent more on the film crystallinity than on the film stoichiometry. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

MEASUREMENT OF TWO-PROTON CORRELATION FROM THE BREAK-UP OF Al-23

Experiments of Al-23 and Mg-22 radioactive beams bombarding a C-12 target at an energy of 60 similar to 70 A MeV have been performed at the projectile fragment separator beamline (RIPS) in the RIKEN Ring Cyclotron Facility to study the two-proton emission from Al-23 and Mg-22 excited states, respectively. The trajectorie of the decay products, namely Na-21 + p + p from Al-23 and Ne-20 + p + p from Mg-22, are clean identified. The relative momentum and opening angle between two protons in the rest frame of three body decay channels are obtained by relativistic-kinematics reconstruction. The results demonstrate that there are some di-proton emission components from He-2 cluster for the excited Al-23 and Mg-22.

Au LX射线发射截面和Al、Ti、Ni表面可见、红外光谱测量

本实验工作是在中国原子能科学研究院的HI-13串列加速器国家实验室第二测量厅原子物理实验平台上完成。本工作采用能量为20-50MeV的高电荷态O5+离子去轰击Au, 测量了不同能量下Au的L1、Lα、Lβ、Lγ的X射线谱，计算了不同能量下各条X射线的产生截面，并与ECPSSR理论计算结果进行了比较。实验结果表明σ（Ll）/σ(Lα) 和σ（Lγ）/σ(Lα)与ECPSSR理论计算结果符合比较好，而对于σ（Lβ）/σ(Lα)，在较低能区实验值略高于理论值。在中国科学院近代物理研究所320kV高电荷态离子实验研究平台上测量了Xeq+ (q=17-29)入射Al、Ti和Ni等表面诱发的可见光和红外光。通过对靶原子光谱线的研究，实验发现，随着入射离子的电荷态增高，原子和离子的各种光谱线可得到有效地激发。低速高电荷态离子入射金属固体表面，靶原子的特征谱线的激发强度，与入射离子的电荷态q密切相关。qc的实验测量值和理论计算值符合的较好