Orthogonal or symplectic Yangians are defined by the Yang-Baxter RLL relation involving the fundamental R matrix with so(n) or sp(2m) symmetry. The conditions on the evaluation of the second order are investigated with respect to the restrictions implied on the representation weights.

Modified Orbital Atomic Study of Dominant Rydberg Series in the Photoionization Spectra of Halogen-like Kr^+ and Xe^+ Ions

For the description of scattering processes and resonances a proper treatment of the continuum is necessary. To achieve such a description in a microscopic many-body approach one has to connect compact configurations that describe the internal part of the wave function with external cluster configurations representing the open channels. We have developed such an approach within fermionic molecular dynamics (FMD). FMD uses a wave-packet basis that allows to describe the internal parts of the wave function and the external cluster channels on equal footing. The matching to the asymptotic behavior as given by two point-like clusters interacting only via Coulomb is performed in the microscopic R-matrix formalism. As a first example we discuss the continuum states in C. We previously studied C in bound state approximation [1]. The focus was on the properties of the Hoyle state, which lies just above the Be-He threshold. Whereas the bound state approximation is expected to work well for a very narrow resonance like the Hoyle state this is no longer true for other resonances like the second 2 state. The resonance position and width for this state could only be determined very recently by direct excitation with photons [2]. The existence and the nature of other states in the continuum is still hotly debated. To address these questions we extend our calculations with a proper treatment of the continuum. Before doing the full FMD calculation a study within the microscopic αcluster model has been performed. The microscopic cluster model with full antisymmetrization and employing a phenomenological two-body interaction proved to be successful in describing many properties of C. In the internal region the Hilbert space is built from three-α configurations on a triangular grid. In the external region Be-He configurations are added. The Be eigenstates are obtained in bound state approximation by diagonalizating configurations up to 9 fm distance. Our results will have to be checked for convergence with respect to increasing the number of included Be (pseudo-) states. Technically the challenge is related to the restoration of rotational symmetry. First the intrinsic wave functions for Be have to be projected on good angular momentum. In a second step the Be-He configurations (with different orientations of the Be spin) have to be projected on total angular momentum. For solving the Schrodinger equation with the microscopic R-matrix method, Hamiltonian and norm kernels for the different channels have to be calculated. In Fig. 1 the calculated phase shifts (from the diagonal

实验通过17F+p共振弹性散射研究了复合核18Ne激发态中与天体核反应14O(α， p)17F相关的共振态性质。利用兰州放射性束流线(RIBLL)对弹核碎裂反应产生的放射性束17F进行了分离和提纯。经过降能后，能量为4.22 AMeV 的17F束流轰击在T2终端的厚氢靶(CH2)n上。 两套∆E-E Si探测器望远镜放置在两个不同的探测角度θlab≈2.3°和14°上，对反冲质子的角度和能量进行了测量。实验观测到了复合核18Ne的几条质子共振能级。通过R-Matrix理论程序对激发函数进行拟合，得到了共振态的能量、 自旋、 宇称和衰变宽度等共振参数。 Resonant properties in18Ne relevant to the stellar reaction of 14O(α, p)17F have been investigated through a resonant elastic scattering of 17F+p. The 17F RI beam was produced via a projectilefragmentation reaction， and subsequently separated and purified by Radioactive Ion beam Line in Lanzhou(RIBLL). After a series of energy degradation，a 4.22 AMeV 17F beam bombarded a thick(CH2)ntarget at T2 terminal. Energy and angle of the recoiled protons were measured by two sets of ∆E-E silicon telescope at θlab≈2.3°，14° respectively. Several resonances in 18Ne were observed，and their resonant parametersincluding energy，spinparity and decay width have been determined by an R-Matrix analysis of the experimental excitation function.

Correlation–polarization effects in electron/positron scattering from acetylene: A comparison of computational models

It is suggested that the R-matrixcross-section for Ps–Xe scattering (Blackwood J E, McAlinden M T andWalters H R J 2002 J. Phys. B: At. Mol. Opt. Phys. 35 2661) is incorrect.

Here we recap the works of two posters presented at the 2002 NASA Laboratory Astrophysics Workshop. The first was Shortcomings of the R-Matrix Method for Treating Dielectronic Recombination. The second was Computation of Dielectronic Recombination Data for the Oxygen-Like Isoelectronic Sequence.

This paper is the second part of two back-to-back papers concerningelectron-impactexcitation of Kr. This part concerns excitation of the individual levels thatconstitute the 4p55p, 4p54d and 4p56s configurations of Kr,at incident electron energies (E0) of 20.0 and 15.0 eV, for scatteringangles (θ) ranging from 10° to 130°. As in part I,excitation cross sections are measured and calculated using the R-matrix (RM)and the unitarized first-order many-body theory (UFOMBT) methods. Comparisonsbetween the present experimental and theoretical results, and also with otherexperimental results, are presented.

For the two-parametric quantized group glq,s(2), the authors calculate the explicit form of the universal R-matrix.

R-matrix study of atomic Rydberg series applications to the nsn's [1]S and nsn'd [1]D series of alkaline-earths

This paper traces the construction of the bracket model of the Jones polynomial, and how this model can be naturally interpreted as a vacuum-vacuum expectation in a combinatorial version of physical theory. From this point of view certain structures such as solutions to the Yang-Baxter equation, and the quantum group for emerge naturally from topological considerations. We then see how quantum groups give rise to invariants of links via solutions to the Yang-Baxter equation. Section 5, is an original treatment of the construction of the universal R-matrix. All the other material has, or will appear elsewhere in similar form.

Abstract The convergence of the eigenchannel (EK) and R-matrix (RM) theories - depending on their free parameters - is numerically investigated by comparing with a simple, analytically solvable model. The comparison shows that the results of the EK-theory are in general closer to the exact solution than those of the RM-theory. Especially in regions of sharp resonances the dependence of the expansion of the wave functions on the interaction radius ac and on the boundary condition Bc is very strong in the RM-theory and one needs very many levels to achieve good results.

The Effect of Variations in the Cue R Matrix Upon the Obtained Policy Equation of Judges