Monopoles at Finite Volume and Temperature in SU(2) Lattice Gauge Theory

We resolve a discrepancy between the SU(2) spacial string tension at finite temperature, and the value obtained by monopoles in the maximum Abelian gauge. Previous work had incorrectly omitted a term due to Dirac sheets. When this term is included, the monopole and full SU(2) determinations of the spacial string tension agree to within the statistical errors of the monopole calculation.Comment: 8 pages, Latex files: msum.tex,msum.aux packaged with uufile

Monopoles contra vortices in SU(2) lattice gauge theory?

We show that the scenario of vortex induced confinement of center--projected SU(2) lattice gauge theory is not necessarily in conflict with the findings in the positive plaquette model.Comment: 3 pages, LaTeX, comment to be published in Phys. Rev.

The Maximal Abelian Gauge, Monopoles, and Vortices in SU(3) Lattice Gauge Theory

We report on calculations of the heavy quark potential in SU(3) lattice gauge theory. Full SU(3) results are compared to three cases which involve gauge-fixing and projection. All of these start from the maximal abelian gauge (MAG), in its simplest form. The first case is abelian projection to U(1)xU(1). The second keeps only the abelian fields of monopoles in the MAG. The third involves an additional gauge-fixing to the indirect maximal center gauge (IMCG), followed by center projection to Z(3). At one gauge fixing/configuration, the string tensions calculated from MAG U(1)xU(1), MAG monopoles, and IMCG Z(3) are all less than the full SU(3) string tension. The projected string tensions further decrease, by approximately 10%, when account is taken of gauge ambiguities. Comparison is made with corresponding results for SU(2). It is emphasized that the formulation of the MAG is more subtle for SU(3) than for SU(2), and that the low string tensions may be caused by the simple MAG form used. A generalized MAG for SU(3) is formulated.Comment: 22 pages, latex, 2 postscript figures. Replaced version has added data at beta=6.0, analysis of Gribov ambiguities, extended tables of results, discussion of scalin

Magnetic Monopoles as Agents of Chiral Symmetry Breaking in U(1) Lattice Gauge Theory

We present results suggesting that magnetic monopoles can account for chiral symmetry breaking in abelian gauge theory. Full U(1) configurations from a lattice simulation are factorized into magnetic monopole and photon contributions. The expectation is computed using the monopole configurations and compared to results for the full U(1) configurations. It is shown that excellent agreement between the two values of is obtained if the effect of photons, which "dress" the composite operator psibarpsi, is included. This can be estimated independently by measurements of the physical fermion mass in the photon background.Comment: 14 pages REVTeX, including 5 figure

Advanced passive communication satellite systems comparison studies. Volume 1 - Summary Final report

Passive communication satellites feasibility for Comsat system - Vol.

Advanced passive communication satellite systems comparison studies. Volume 2 - Technical discussion Final report

Passive communication satellites feasibility for Comsat system - Vol.

Wall-temperature effects on the aerodynamics of a hydrogen-fueled transport concept in Mach 8 blowdown and shock tunnels

Results are presented from two separate tests on the same blended wing-body hydrogen fueled transport model at a Mach number of about 8 and a range of Reynolds numbers (based on theoretical body length) of 0.597 x 10 to the 6th power to about 156.22 x 10 to the 6th power. Tests were made in conventional hypersonic blowdown tunnel and a hypersonic shock tunnel at angles of attack of -2 deg to about 8 deg, with an extensive study made at a constant angle of attack of 3 deg. The model boundary-layer flow varied from laminar at the lower Reynolds numbers to predominantly turbulent at the higher Reynolds numbers. Model wall temperatures and stream static temperatures varied widely between the two tests, particularly at the lower Reynolds numbers. These temperature differences resulted in marked variations of the axial-force coefficients between the two tests, due in part to the effects of induced pressure and viscous interaction variations. The normal-force coefficient was essentially independent of Reynolds number. Analysis of results utilized current theoretical computer programs and basic boundary-layer theory