Image display system 511

The experience of the Idaho Department of Water Resources Remote Sensing Unit in bringing on line their System 511 is described. The system 511 is run on a PDP minicomputer. The minimum system hardware configuration is an 11/34 with a minimum core of 128 K word, 10 megabytes of direct access disk and a floating point processor. The required software configuration is an RSX 11M V 3.2 operating system with a FORTRAN IV plus compiler. The structure of System 511 is a series of hierarchical modular software units. Problems occurring during the systems installation are discussed, and the system operating and error detection capabilities and documentation evaluated

Spin and angular momentum in the nucleon

Using the covariant spectator theory (CST), we present the results of a valence quark-diquark model calculation of the nucleon structure function f(x) measured in unpolarized deep inelastic scattering (DIS), and the structure functions g1(x) and g2(x) measured in DIS using polarized beams and targets. Parameters of the wave functions are adjusted to fit all the data. The fit fixes both the shape of the wave functions and the relative strength of each component. Two solutions are found that fit f(x) and g1(x), but only one of these gives a good description of g2(x). This fit requires the nucleon CST wave functions contain a large D-wave component (about 35%) and a small P-wave component (about 0.6%). The significance of these results is discussed.Comment: 27 pages; 13 figure

Poisoning of Hydrogen Dissociation at Pd (100) by Adsorbed Sulfur Studied by ab initio Quantum Dynamics and ab initio Molecular Dynamics

We report calculations of the dissociative adsorption of H_2 at Pd (100) covered with 1/4 monolayer of sulfur using quantum dynamics as well as molecular dynamics and taking all six degrees of freedom of the two H atoms fully into account. The ab initio potential-energy surface (PES) is found to be very strongly corrugated. In particular we discuss the influence of tunneling, zero-point vibrations, localization of the nuclei's wave function when narrow valleys of the PES are passed, steering of the approaching H_2 molecules towards low energy barrier configurations, and the time scales of the center of mass motion and the other degrees of freedom. Several ``established'' concepts, which were derived from low-dimensional dynamical studies, are shown to be not valid.Comment: 4 pages, 3 figures, submitted to Surf. Sci. Lett. Other related publications can be found at http://www.rz-berlin.mpg.de/th/paper.htm

Large-N limit of the two-dimensoinal Yang-Mills theory on surfaces with boundaries

The large-N limit of the two-dimensional U$(N)$ Yang-Mills theory on an arbitrary orientable compact surface with boundaries is studied. It is shown that if the holonomies of the gauge field on boundaries are near the identity, then the critical behavior of the system is the same as that of an orientable surface without boundaries with the same genus but with a modified area. The diffenece between this effective area and the real area of the surface is obtained and shown to be a function of the boundary conditions (holonomies) only. A similar result is shown to hold for the group SU$(N)$ and other simple groups.Comment: 11 pages, LaTeX2

Explosive hypervelocity drag accelerator

Accelerator for launching hypervelocity projectile by drag force of jet produced by gaseous explosive product

The moduli space of (111)-polarized abelian surfaces is unirational

We prove that the moduli space $\cal A$11lev of (1,11)-polarized Abelian surfaces with level structure of canonical type is birational to Klein's cubic hypersurface in P4. Therefore, $\cal A$11lev is unirational but not rational, and there are no Γ11-cusp forms of weight 3. The same methods also provide an easy proof of the rationality of $\cal A$9lev

Large-N limit of the generalized 2D Yang-Mills theory on cylinder

Using the collective field theory approach of large-N generalized two-dimensional Yang-Mills theory on cylinder, it is shown that the classical equation of motion of collective field is a generalized Hopf equation. Then, using the Itzykson-Zuber integral at the large-N limit, it is found that the classical Young tableau density, which satisfies the saddle-point equation and determines the large-N limit of free energy, is the inverse of the solution of this generalized Hopf equation, at a certain point.Comment: 11 pages, add a paragraph after eq.(20) and add one reference, accepted for publication in: Nucl. Phys. B (2000