Supersymmetric penguin contributions to the decay b -> s gamma with non-universal squarks masses

We give explicit expressions for the amplitudes associated with the supersymmetric contributions to the process: b -> s gamma in the context of SUSY extensions of Standard Model with non-universal soft SUSY breaking terms. From experimental data, we deduce the limits on the squark mass insertions obtained from different contributions (gluinos, neutralinos and charginos).Comment: 13 pages, 6 figures, changes: added remarks and new referenc

Standard Model Baryogenesis

Simply on CP arguments, we argue against a Standard Model explanation of baryogenesis via the charge transport mechanism. A CP-asymmetry is found in the reflection coefficients of quarks hitting the electroweak phase boundary created during a first order phase transition. The problem is analyzed both in an academic zero temperature case and in the realistic finite temperature one. At finite temperature, a crucial role is played by the damping rate of quasi-quarks in a hot plasma, which induces loss of spatial coherence and suppresses reflection on the boundary even at tree-level. The resulting baryon asymmetry is many orders of magnitude below what observation requires. We comment as well on related works.Comment: 10 pages, CERN-TH. 7368/94, LPTHE Orsay-94/71, HD-THEP-94-2

A laser velocimeter system for large-scale aerodynamic testing

A unique laser velocimeter was developed that is capable of sensing two orthogonal velocity components from a variable remote distance of 2.6 to 10 m for use in the 40- by 80-Foot and 80- by 120-Foot Wind Tunnels and the Outdoor Aerodynamic Research Facility at Ames Research Center. The system hardware, positioning instrumentation, and data acquisition equipment are described in detail; system capabilities and limitations are discussed; and expressions for systematic and statistical accuracy are developed. Direct and coupled laboratory measurements taken with the system are compared with measurements taken with a laser velocimeter of higher spatial resolution, and sample data taken in the open circuit exhaust flow of a 1/50-scale model of the 80- by 120-Foot Wind Tunnel are presented

Laser velocimetry in the low-speed wind tunnels at Ames Research Center

The historical development of laser velocimetry and its application to low-speed (less than 100 m/sec) aerodynamic flows in the subsonic wind tunnels at Ames Research Center is reviewed. A fully three dimensional velocimeter for the Ames 7- by 10-Foot Wind Tunnel is described, and its capabilities are presented through sample data from a recent experiment. Finally, a long-range (2.6 to 10 m) velocimeter that is designed to be installed within the test section of the Ames 40- by 80-Foot Wind Tunnel is described and sample data are presented

Quantum Stability of the Phase Transition in Rigid QED

Rigid QED is a renormalizable generalization of Feynman's space-time action characterized by the addition of the curvature of the world line (rigidity). We have recently shown that a phase transition occurs in the leading approximation of the large N limit. The disordered phase essentially coincides with ordinary QED, while the ordered phase is a new theory. We have further shown that both phases of the quantum theory are free of ghosts and tachyons. In this letter, we study the first sub-leading quantum corrections leading to the renormalized mass gap equation. Our main result is that the phase transition does indeed survive these quantum fluctuations.Comment: PHYZZX, 9 pages, 3 Postscript figures, to be published in Nucl. Phys.

THE EFFECTS OF FATIGUE AND BACKPACK DESIGN ON POSTURE

The purpose of this study was to determine the effects of fatigue and backpack design on head and trunk position. Twenty four young female volunteers were filmed while walking 3200m around a track with a suspension and student backpack, as well as in an unloaded control condition. Head and trunk absolute angles were recorded after 400m and again at 2800m for all three conditions. A repeated measures ANOVA indicated that significant differences did occur between the two backpacks in head flexion, maximal trunk extension, and total range of motion of the trunk. Fatigue differences were seen in head flexion and maximal trunk flexion. It was concluded that even with relatively light loads a supported backpack was superior to a student backpack