光的碰撞再分布

光的碰撞再分布是２０多年来发展起来的研究原子碰撞过程的新技术，目前已成为研究原子相互作用的强有力的工具。文章简要介绍了碰撞再分布技术的基本原理和典型实验，并给出了应用实例。     

Studies of ion energy and yield from argon clusters heated by intense femtosecond laser pulses

Using time-of-flight spectrometry, the interaction of intense femtosecond laser pulses with argon clusters has been studied by measuring the energy and yield of emitted ions. With two different supersonic nozzles, the dependence of average ion energy on cluster size in a large range of has been measured. The experimental results indicate that when the cluster size , the average ion energy Coulomb explosion is the dominant expansion mechanism. Beyond this size, the average ion energy gets saturated gradually, the clusters exhibit a mixed Coulomb-hydrodynamic expansion behavior. We also find that with the increasing gas backing pressure, there is a maximum ion yield, the ion yield decreases as the gas backing pressure is further increased.     

Dynamics of laser-induced shock wave by optical probe in air

A new simple optical system based on optical beam deflection combining the holophote corner cube was developed in order to study the dynamics of laser-induced shock waves in air. In this method, we adopt a He-Ne laser beam as the detection beam. The He-Ne laser beam, reflected by corner cube, intersects the propagating shock wave at two successive positions. The measurement of the shock wave velocity benefits from the double peak signals induced by the same acting laser pulse, which is calculated from the time interval between the corresponding oscilloscope signals and the distance of the two He-Ne laser beams. By virtue of this setup, we are also able to determine the pressure of the generated shock waves. It is shown that this method is simple with a fairly good precision and is much easier than the conventional methods used for this task.     

102Ru核振动到转动演化的微观研究

基于微观sdIBM-2方案和实验单粒子能量值,在最普遍的哈密顿量下,用两组不同的核子.核子等效相互作用参数,分别很好地再现了102Ru核的振动带能谱和转动带能谱及其演化过程.微观和唯象的研究指认:1)这两种激发模式的共存区是能态81 -121 (即Ex=2.500-4.000 MeV);态81 是振动模式占据优势的能态,态121 是转动模式占据优势的能态,而状态101 则是两种模式的中立能态;2)态121 是141 态退耦到态101 辐射光子相变后的中间能态;3)从基态起直到201 态的yrast态全都是集体态,而以后出现的第一个拆对顺排态很可能就是中子h11/2的两准粒子态;4)这种结构的过渡不是很剧烈的,而是通过玻色子结构常数在过渡区中不大的改变来实现的.     

近自然彩色图像融合算法及其实时处理系统的发展

在军事和生产领域,特别是在极其恶劣的可视条件下,图像融合技术越来越强调融合效果显示的"近自然"感觉,以及人类视觉感知的要求。从彩色图像融合算法的发展概况出发,着重介绍了两种具有代表性的基于视觉特性的近自然彩色图像融合方法,并特别阐述了课题组近期开展的相关算法研究成果。总结了国内外实时彩色图像融合系统的发展现状,概括了课题组已具备的硬件实验基础,综合分析了实时彩色图像融合技术的若干关键技术,如多源图像特征分析、实时图像配准、融合图像后处理等。针对实时图像融合技术的应用状况,提出图像融合系统未来的发展趋势。     

Dark matter results from 100 live days of XENON100 data

We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of (1.8 ± 0.6) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above 7.0 × 10(-45) cm(2) for a WIMP mass of 50 GeV/c(2) at 90% confidence level.     

Persistence Properties and Unique Continuation of Solutions to a Two-component Camassa–Holm Equation

We will consider a two-component Camassa–Holm system which arises in shallow water theory. The present work is mainly concerned with persistence properties and unique continuation to this new kind of system, in view of the classical Camassa–Holm equation. Firstly, it is shown that there are three results about these properties of the strong solutions. Then we also investigate the infinite propagation speed in the sense that the corresponding solution does not have compact spatial support for t > 0 though the initial data belongs to C₀^￥(BbbR)C_{0}^{infty}(Bbb{R}).     

ZnO:Ag film growth on Si substrate with ZnO buffer layer by rf sputtering

ZnO buffer layers were deposited on n-Si (1 0 0) substrate by rf magnetron sputtering at a lower power of 40 W. Then Ag-doped ZnO (SZO) films were deposited on buffered and non-buffered Si at a higher sputtering power of 100 W. The effects of buffer layer on the structural, electrical and optical properties of SZO films were investigated. The three-dimensional island growth process of ZnO buffer layer was discussed. The energy band diagram of p-SZO/n-Si heterojunction was constructed based on Anderson's model. Results show the ZnO buffer layer leads to better properties of SZO film, including larger grain size, smoother surface, higher carrier mobility, better rectifying behavior, lower interface state density, and weaker deep-level emission. It is because the ZnO buffer layer effectively relaxes the partial stress induced by the large lattice mismatch between SZO and Si.     

模式偏置波前传感器理论模拟及实验验证

将模式偏置法与全息多重存储法波前传感器原理联系起来,通过研究模式偏置波前传感器的输出响应特性,间接得到全息模式波前传感器的运行规律.对模式偏置波前传感器进行理论分析与总结,并建立简化模型,针对若干阶Zernike像差,通过数值模拟对理论结果进行验证.模拟结果显示:传感器输出信号与各种类型待测像差系数有不同的变化关系,这...