Revised Academic Hardiness Scale Factor Structure in College Students

The construct of academic hardiness has gained attention in recent literature as an antecedent of successful academic performance and enrollment in higher education. Although academic hardiness scales have been validated for use with elementary and high school students, none have been examined in college students. The current study investigated the factor structure of the Revised Academic Hardiness Scale using two college student samples. Exploratory analyses found a five-factor structure in a sample of 454 students at a large university. Confirmatory analyses indicated adequate to good model fit for this solution in a sample of 160 students at a small college

Advanced Grid programming with components: a biometric identification case study

Component-oriented software development has been attracting increasing attention for building complex distributed applications. A new infrastructure supporting this advanced concept is our prototype component framework based on the Grid component model. This paper provides an overview of the component framework and presents a case study where we utilise the component-oriented approach to develop a business process application for a biometric identification system. We then introduce the tools being developed as part of an integrated development environment to enable graphical component-based development of Grid applications. Finally, we report our initial findings and experiences of efficiently using the component framework and set of software tools

(e,2e) measurements on xeon: reexamination of the fine-structure effect

The process of electron scattering from heavy target atoms is of considerable interest due to the enhanced role of relativistic effects and distortion of the electron trajectories resulting from the large value of nuclear charge. Here we present (e,2e) ionization measurements and distorted-wave Born approximation calculations for the scattering of spin-polarized electrons from xenon atoms in which the fine-structure levels of the residual ion are resolved. Comparison of measurements performed using a high-sensitivity toroidal analyzer spectrometer with the predictions of sophisticated calculations provide an improved understanding of the ionization dynamics of heavy target atoms and the treatment of electron exchange processes

(e,2e) Measurements on Xenon: Reexamination of the Fine-Structure Effect

The process of electron scattering from heavy target atoms is of considerable interest due to the enhanced role of relativistic effects and distortion of the electron trajectories resulting from the large value of nuclear charge. Here we present (e,2e) ionization measurements and distorted-wave Born approximation calculations for the scattering of spin-polarized electrons from xenon atoms in which the fine-structure levels of the residual ion are resolved. Comparison of measurements performed using a high-sensitivity toroidal analyzer spectrometer with the predictions of sophisticated calculations provide an improved understanding of the ionization dynamics of heavy target atoms and the treatment of electron exchange processes

Plasmon-assisted electron-electron collisions at metallic surfaces

We present a theoretical treatment for the ejection of a secondary electron from a clean metallic surface induced by the impact of a fast primary electron. Assuming a direct scattering between the incident, primary electron and the electron in a metal, we calculate the electron-pair energy distributions at the surfaces of Al and Be. Different models for the screening of the electron-electron interaction are examined and the footprints of the surface and the bulk plasmon modes are determined and analyzed. The formulated theoretical approach is compared with the available experimental data on the electron-pair emission from Al.Comment: 30 pages, 9 figure

Fully Differential Cross Sections for Electron-Impact Excitation-Ionization of Aligned D₂

We examine fully differential cross sections for 176 eV electron-impact dissociative excitation-ionization of orientated D2 for transitions to final ion states 2sσg, 2pσu, and 2pπu. In previous work [Phys. Rev. A 88, 062705 (2013)PLRAAN1050-294710.1103/PhysRevA.88.062705], we calculated these cross sections using the molecular four-body distorted wave (M4DW) method with the ground-state D2 wave function being approximated by a product of two Dyson 1s-type orbitals. The theoretical results were compared with experimental measurements for five different orientations of the target molecule (four in the scattering plane and one perpendicular to the scattering plane). For the unresolved 2sσg + 2pπu final states, good agreement with experiment was found for two of the five measured orientations, and for the 2pσu final state, good agreement was found for three of the five orientations. However, theory was a factor of 200 smaller than experiment for the 2pσu state. In this paper, we investigate the importance of the approximation for the molecular ground-state wave function by repeating the M4DW calculation using a better variational wave function for the ground state

Quasiparticle properties in a density functional framework

We propose a framework to construct the ground-state energy and density matrix of an N-electron system by solving selfconsistently a set of single-particle equations. The method can be viewed as a non-trivial extension of the Kohn-Sham scheme (which is embedded as a special case). It is based on separating the Green's function into a quasi-particle part and a background part, and expressing only the background part as a functional of the density matrix. The calculated single-particle energies and wave functions have a clear physical interpretation as quasiparticle energies and orbitals.Comment: 12 pages, 1 figure, to be published in Phys. Rev.

Experimental and theoretical cross sections for molecular-frame electron-impact excitation-ionization of D 2

We present both experimental and theoretical results for the dissociative ionization of D2 molecules induced by electron impact. Cross sections are determined in the molecular frame and are fully differential in the energies and emission angles of the di

Fully differential cross-section measurements for electron-impact ionization of argon over the complete in-plane angular range

The triple differential cross section for electron-impact ionization of the 3p orbital of argon by 113.5 eV incident electrons has been measured using a magnetic angle changer in a conventional (e,2e) spectrometer. Results are presented for 2 eV ejected electrons over an extended angular range, and over the complete coplanar scattering plane for 5 eV ejected electrons. The data reveal previously unobserved structures, and are compared with recent distorted-wave Born approximation (DWBA) and hybrid DWBA R-matrix calculations. Large discrepancies exist between experiment and both calculations in the accessed regions.M. A. Stevenson and B. Lohman