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The primary goal of the Adventures in Supercomputing activity is to capture and cultivate the interest of minority and disadvantaged elementary through high school students in science, mathematics, and computing. The program consists of five major components: (1) a summer institute for teacher enhancement and curriculum material development; (2) a fully supported classroom computing environment in participating schools; (3) summer research positions in high-performance computing for selected teachers from the program; (4) collaboration with the Colleges of Education in each laboratory's local university; and (5) an in-depth and ongoing assessment for both formative and summative evaluation of the program. These components will be extended to lower-grade levels over the course of the five-year activity. >

Within the realm of education, seldom does an innovative program become available with the potential to change an educator's teaching methodology. Adventures in Supercomputing (AiS), sponsored by the US Department of Energy (DOE), is such a program. It is a program for high school teachers that changes the teacher paradigm from a teacher-directed approach of teaching to a student-centered approach. Not only is the process of teaching changed, but the cross-curricula integration within the AiS materials is remarkable. Written from a teacher's perspective, this paper describes the AiS program and its effects on teachers and students, primarily at Wartburg Central High School, in Wartburg, Tennessee. The AiS program in Tennessee is sponsored by Oak Ridge National Laboratory.

Adventures in Supercomputing (AiS) is an innovative educational outreach program to address the shortfall in human resources in science and engineering. The program has been funded since 1992 as part of the Department of Energy's High Performance Computing and Communications Program. Supercomputers are used both as a magnet to draw students into science and engineering and as an enabling tool to assist them to explore simulations based on mathematical or physical models. The program presently involves 69 high schools and 5 middle schools in five states: Alabama, Colorado, Iowa, New Mexico, and Tennessee. The primary goal of this program is to capture and cultivate the interest of minority, female and disadvantaged students in science, mathematics, and computing. By improving the teachers' computer expertise and scientific knowledge through intense training, teachers are able to reach out confidently to this target group of students. An environment to support computing education for both students and teachers is strengthened during the year through continued technical support. The paper discusses methods of encouraging minorities, women, and disadvantaged students to become involved in the Adventures in Supercomputing program. It shares achievements of this diverse school population over the past years as these students engage in long term computational science projects. It also shares the assessment results, showing the success of the program.

We have analyzed K+p cross-section and polarization data in the momentum range 0.78–2.53 GeV/c. Single energy fits were made using an ACE parametrization which had no cutoff in J, was analytic and had Regge-asymptotic behavior in the cut cos θ plane, and contained explicit contributions from P, ϱ, A2, Λ, Σ, and low-mass di-pion exchange. Direct channel analyticity constraints were imposed by a partial-wave dispersion relation interpolation procedure, fitting expansions in regulated-norm optimal bases to each partial wave which entered as a search parameter in the single energy fits. Output from these two programs was then used for a simultaneous fit by a linearized least squares program which provided input for another iterative fitting cycle. We find no strong evidence for the existence of exotic resonances. The method of analytic smoothing, in comparison with “shortest path” methods, is found to allow more significant threshold structure to appear in the amplitudes.

Previously suggested two-variable expansions of three-body decay amplitudes in terms of harmonic functions of an O(4) group are discussed and applied to analyze the Dalitz-plot distribution of over 3.2 million K±→π±π±π∓ decay events. Among the general features of the O(4) expansions we wish to stress that they are written in the c.m. system of two of the final particles, the angular momentum of which is displayed explicitly, and that each term in the expansion has a good behavior at the threshold, pseudothreshold, and at the boundary of the physical region. We analyze the recent data of Ford et al. on charged K→3π decays, using both O(4) expansion and the standard power-series expansion in terms of the Dalitz-Fabri variables. In both cases it is perfectly adequate to keep four terms in the corresponding expansion. The χ2 fit is marginally better for the O(4) expansion. We conclude that the K→3π Dalitz plot has too little structure in it to provide a real test of the advantages or disadvantages of different treatments. It is thus most desirable to apply the O(4) expansions to Dalitz plots of other processes, like η→3π or p¯n→πππ. No conclusive evidence is found for CP violation. However, the "linear" term in the O(4) expansion of the difference between the squared matrix elements for K+ and K− decays does differ from zero by more than two standard deviations. The effect is stable with regard to the number of terms kept in the expansions. An important distinctive feature of the O(4) expansions is their intimate relation to two-variable O(3, 1) expansions of physical scattering amplitudes.

We have analyzed data on K+p elastic scattering at 21 momenta covering the range 0.5–2.5 GeV/c. We present results of three phase shift analyses. One of these is an energy independent accelerated convergence expansion (ACE) analysis in which high partial waves are included through use of conformal mapping as suggested by analytic approximation theory. The other two are an energy independent and an energy smoothed conventional analysis. The ACE method gave, with the same number of parameters, a 20% average improvement in x2 as well as more unique phase shift solutions. The high partial waves gave significant contributions to total and inelastic cross sections. The ACE method is also sensitive to the value of gΛΣ2 = gKΛN2 + gKΣN2; we have obtained the value gΛΣ2 = 15.2 ± 2.3.

The experimental Dalitz plot for $\overline{p}n\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}}$ annihilations at rest is analyzed, using previously suggested two-variable expansions of decay amplitudes, based on the representation theory of the group O(4). A fair fit to the Dalitz plot is obtained by minimizing the ${\ensuremath{\chi}}^{2}$ function, assuming that the annihilation proceeds from a protium state of definite (but unspecified) angular momentum $J$ (or from several such states). Fits with 2, 4, 6, and 9 free parameters are considered, the values of the parameters are essentially stable with respect to the "cutoff" of the expansion, and the solutions are unique. The fit is purely kinematical, in that no assumptions are made about the initial and final state or the annihilation dynamics. An analysis of the contribution of various parts of the Dalitz plot to the over-all ${\ensuremath{\chi}}^{2}$ suggests that the fit would be considerably improved by including, e.g., $\ensuremath{\rho}$- and $f$-meson final-state resonances explicitly. We compare the O(4) expansions with a power-series expansion in Dalitz-Fabri variables and also with various models that have been recently applied, in particular the Veneziano model and its generalizations and various final-state-interaction models.

An analysis of the available data below 2.24-GeV c.m. energy for the process $\ensuremath{\gamma}p\ensuremath{\rightarrow}\ensuremath{\eta}p$ yields values of $G\ensuremath{\equiv}\ensuremath{\Gamma}(R\ensuremath{\rightarrow}\ensuremath{\gamma}p)\ensuremath{\Gamma}(R\ensuremath{\rightarrow}\ensuremath{\eta}p)$ for several $s$-channel resonances, $R$. By varying the details of the direct-channel isobar model it is found that the values of $G$ are reasonably model-independent. When these values are combined with information from other reactions it is possible to calculate electromagnetic widths for the important resonance states in this process. These include essential contributions from ${S}_{11}$ and ${P}_{11}$ states; in addition, admixtures of ${P}_{13}$, ${D}_{13}$, ${F}_{17}$, and ${G}_{17}$ resonances are also needed in order to obtain a good fit to the data. An excellent fit is found by including some recently conjectured stray baryonic states which do not couple significantly to the $\ensuremath{\pi}N$ channel.

This handbook tells the casual user how to run the program MHD2V106, a computer program to determine linear growth rates and eigenmodes for an ideal MHD plasma in a cylinder or toroid of rectangular cross section.

The nonlinear evolution of ideal MHD internal instabilities is investigated in straight cylindrical geometry by means of a 3-D initial-value computer code. These instabilities are characterized by pairs of velocity vortex cells rolling off each other and helically twisted down the plasma column. The cells persist until the poloidal velocity saturates at a few tenths of the Alfven velocity. The nonlinear phase is characterized by convection around these essentially fixed vortex cells. For example, the initially centrally peaked temperature profile is convected out and around to form an annulus of high temperature surrounding a small region of lower temperature. Weak, centrally localized instabilities do not alter the edge of the plasma. Strong, large-scale instabilities, resulting from a stronger longitudinal equilibrium current, drive the plasma against the wall. After three examples of instability are analyzed in detail, the numerical methods and their verification are discussed.

We have studied the nonlinear evolution of fixed-boundary instabilities using a 3-D ideal-MHD computer simulation. Here, we concentrate on the effect of elongation and peaked profile. It is found that the dominant process is convection around essentially fixed velocity vortex cells.