Dibaryons with strangeness: their weak nonleptonic decay using SU(3) symmetry and how to find them in relativistic heavy-Ion collisions

Weak SU(3) symmetry is successfully applied to the weak hadronic decay amplitudes of octet hyperons. Weak nonmesonic and mesonic decays of various dibaryons with strangeness, their dominant decay modes, and lifetimes are calculated. Production estimates for the Brookhaven Relativistic Heavy Ion Collider are presented employing wave-function coalescence. Signals for detecting strange dibaryon states in heavy-ion collisions and revealing information about the unknown hyperon-hyperon interactions are outlined.     

Burst imaging: rotation artifacts and how to correct them

The effect of coherent rotational motion on images acquired with the ultrafast single-shot spin-echo Burst sequence has been analyzed. Previous experience has demonstrated that sample rotation during Burst experiments has the potential to cause severe image artifacts. In this paper we show that no distortions are visible when the readout gradient is parallel to the rotation axis, but that there is a very distinctive behavior for the case of the rotation axis orthogonal to the imaging plane. The mathematical expression that describes the resulting signal is presented and is used as a basis for a method of correcting the k-space data. The conditions under which undistorted images may be recovered are discussed. It is shown that there is an asymmetry, dependent on the rotation direction, in both the manifestation of the artifact and the range of angular velocities over which one can correct the images. Data from an agar gel phantom rotating at a known rate are used to show how the theory is successful at reconstructing images, with no free parameters. The range of angular velocities over which correction is possible depends on the timing parameters of the pulse sequence, but for these data was -0.016 < omega less, similar 0.1 revolutions/s. Volunteer experiments have confirmed that the theory is applicable to patient motion and can correct motional distortion even when the exact rate is not known a priori. By optimizing the reconstruction to restore a known sample geometry/aspect ratio, an estimate of the rotation angular frequency is obtained with a precision of +/-10%.     

How to find two more narrow states of charmonium

Two out of the three still missing D-states of charmonium, with masses around 3.8 GeV, are shown to be narrow and detectable in hadronic collisions. They are the J^PC = 2^?? state, to be seen through its decay into ψππ or ψη, and the 2^?+ state with a favoured decay mode ψ3π. Electromagnetic decay modes are also discussed.     

Stepped polarization states: Representation and its applications to optical sensing and measurement

By the introduction of proper step functions, the alternately polarized light with stepped polarization states can be represented as one concise Jones or Stokes vector, or one complex number. These expressions can simplify the analysis and design of polarization-multiplexed optical systems. Both azimuth-stepping and ellipticity-stepping polarization states can be generated by the use of an electrooptic modulator based on dual transverse Pockels effect. In polarimetric sensing and measurement systems, the application of stepped polarization states can both simplify signal processing, and improve measurement sensitivity and signal to noise ratio (SNR).     

Attacks on practical quantum key distribution systems (and how to prevent them)

With the emergence of an information society, the idea of protecting sensitive data is steadily gaining importance. Conventional encryption methods may not be sufficient to guarantee data protection in the future. Quantum key distribution (QKD) is an emerging technology that exploits fundamental physical properties to guarantee perfect security in theory. However, it is not easy to ensure in practice that the implementations of QKD systems are exactly in line with the theoretical specifications. Such theory–practice deviations can open loopholes and compromise security. Several such loopholes have been discovered and investigated in the last decade. These activities have motivated the proposal and implementation of appropriate countermeasures, thereby preventing future attacks and enhancing the practical security of QKD. This article introduces the so-called field of quantum hacking by summarising a variety of attacks and their prevention mechanisms.     

Trapped states and transitions between them in double-well pseudopotentials

We analyze a model of a double-well pseudopotential (DWPP), based in the 1D Gross-Pitaevskii equation with a spatially modulated self-attractive nonlinearity. In the limit case when the DWPP structure reduces to the local nonlinearity coefficient represented by a set of two delta-functions, analytical solutions are obtained for symmetric, antisymmetric and asymmetric states. In this case, the transition from symmetric to asymmetric states, i.e., a spontaneous-symmetry-breaking (SSB) bifurcation, is subcritical. Numerical analysis demonstrates that the symmetric states are stable up to the SSB point, while emerging asymmetric states (together with all antisymmetric solutions) are unstable in the delta-function model. In a general model, which features a finite width of the nonlinear-potential wells, the asymmetric states quickly become stable, simultaneously with the switch of the bifurcation into the supercritical type. Antisymmetric solutions may also enjoy stabilization in the finite-width DWPP structure, demonstrating a bistability involving the asymmetric states. The symmetric states require a finite norm for their existence. A full diagram for the existence and stability of the trapped states is produced for the general model.     

Generation of non-classical states from an optical parametric oscillator/amplifier and their applications

Quantum information and quantum optics are rapidly advancing areas of modern physics. As an important device in quantum optics and quantum information, the optical parametric amplifier/oscillator (OPA/O) has been extensively studied and applied to the generation of non-classical state since the 1980s. This article reviews the progress in the generation of non-classical state from an OPO/A and application of twin beams in quantum optics and quantum information      

Resonant states and their uses

The paper shows, for a simple model, how the wave functions belonging to complex energy eigenvalues (resonance states) can be regarded as part of a complete set of states, containing also bound states and a continuum of (generally complex) wave functions. This forms the basis of an expansion, which is used to describe inelastic scattering in the plane-wave Born approximation, taking the same simple model for the target.     

Generating function of product of bivariate Hermite polynomials and their applications in studying quantum optical states

By virtue of the operator-Hermite-polynomial method, we derive some new generating function formulas of the product of two bivariate Hermite polynomials. Their applications in studying quantum optical states are presented.     

核酸识体的研究及应用

核酸识体(aptamer)是近年来发展起来的一类经体外人工进化程序筛选出的寡聚核苷酸。它能高效、特异地结合各种配体，在蛋白质的分析检测、医学诊断治疗、生物传感器和分子开关的开发等方面有很大的应用前景，文章对核酸识体的研究和应用进展进行了综述。     

Special functions related to Dedekind-type DC-sums and their applications

In this paper, we construct trigonometric functions in the form of a sum T _p (h, k) which is referred to as a Dedekind-type DC-(Dahee and Changhee) sum. We establish analytic properties of this sum, find its trigonometric representations, and prove a reciprocity theorem for these sums. Furthermore, we obtain relationships between the Clausen functions, polylogarithm function, Hurwitz zeta function, generalized Lambert series (G-series), Hardy-Berndt sums, and the sum T _p (h, k). We also give some applications related to these sums and functions.     

Identifying and comparing states of time-delayed systems: phase diagrams and applications to human motor control systems

A data driven characterization of time-delayed stochastic systems is proposed in terms of linear delay differential equations and two drift parameters. It is shown how these parameters determine the states of such systems with respect to generalized phase diagrams. This approach allows for a comparison of systems with different parameters as exemplified for two motor control tasks: tracking and force production.     

Infra-red lasers and their applications

Properties and applications of infra-red lasers are reviewed, with particular emphasis on those likely to be fundametnally important in energy production, materials and data processing.     

Free-electron lasers and their applications

We review the classical theory of the free-electron laser and discuss possible applications in laser fusion, laser-induced chemistry, biochemistry, and solid-state physics. The possibility of using optical wigglers to reach the VUV and soft X-ray regimes is also analysed.     

原子漏斗及其应用

文章简单介绍了磁、光原子漏斗的基本原理，详细综述了各种原子漏斗方案及其实验结果．这些漏斗方案主要包括采用红失谐高斯光束、蓝失谐消逝波光场和空心光束串联而成的光学原子漏斗，采用载流导线的静磁原子漏斗以及采用磁光凝胶构成的磁光原子漏斗．文章最后还简单介绍了原子漏斗在原子光学领域中的潜在应用．     

Pre-symplectic algebroids and their applications

In this paper, we introduce the notion of a pre-symplectic algebroid and show that there is a one-to-one correspondence between pre-symplectic algebroids and symplectic Lie algebroids. This result is the geometric generalization of the relation between left-symmetric algebras and symplectic (Frobenius) Lie algebras. Although pre-symplectic algebroids are not left-symmetric algebroids, they still can be viewed as the underlying structures of symplectic Lie algebroids. Then we study exact pre-symplectic algebroids and show that they are classified by the third cohomology group of a left-symmetric algebroid. Finally, we study para-complex pre-symplectic algebroids. Associated with a para-complex pre-symplectic algebroid, there is a pseudo-Riemannian Lie algebroid. The multiplication in a para-complex pre-symplectic algebroid characterizes the restriction to the Lagrangian subalgebroids of the Levi–Civita connection in the corresponding pseudo-Riemannian Lie algebroid.