Composite bulkhead fabrication development

Composite bulkhead is produced by a fabrication concept utilizing vacuum and/or autoclave pressure to hold preformed welded sandwich elements in place during bonding and aging

BFKL Physics in Jet Production at e+e- colliders

Virtual photon scattering in $e^+e^-$ collisions can result in events with the electron-positron pair at large rapidity separation with hadronic activity in between. The BFKL equation resums large logarithms that dominate the cross section for this process. We report here on a Monte Carlo method for solving the BFKL equation that allows kinematic constraints to be taken into account and show results for $e^+e^-$ collisions.Comment: 3 pages, Latex, talk presented at the 2000 Meeting of the Division of Particles and Fields of the APS, Columbus, OH, August 9--12, 200

The Collision Energy Dependence of Dijet Cross Sections as a Probe of BFKL Physics

The dependence of the subprocess cross section for dijet production at fixed transverse momentum on the (large) rapidity separation Delta y of the dijets can be used to test for `BFKL physics', i.e. the presence of higher--order (alphas log(Delta y)^n contributions. Unfortunately in practice these subtle effects are masked by the additional, stronger dependence arising from the parton distributions. We propose a simple ratio test using two different collider energies n which the parton distribution dependence largely cancels. Such a ratio does distinguish between the `asymptotic' analytic BFKL and lowest-order QCD predictions. However, when subasymptotic effects from overall energy-momentum conservation are included, the BFKL predictions for present collider energies change qualitatively. In particular, the real gluon emission contributions to the BFKL cross section are suppressed. The proposed ratio therefore provides an interesting laboratory for studying the interplay of leading-logarithm and kinematic effects.Comment: 13 pages LaTeX, uses epsf; Fig. 2 corrected; conclusions unchanged; version to be published in Phys. Lett.

Progress Towards a Generator for BFKL Physics

In certain regions of phase space in jet production, large logarithms can arise which are resummed by the BFKL equation. Linear colliders can potentially be excellent places to study BFKL effects in jet production. We discuss an approach to BFKL calculations which incorporates kinematic effects explicitly and can be implemented in an event generator.Comment: 4 pages including 2 figures, Latex, uses epsfig, aipproc.sty; talk presented at Linear Collider Workshop 2000, Fermilab, Batavia, IL, Oct. 24--28, 200

Shuttle orbiter S-band quad antenna switching evaluation

Automatic switching of the shuttle orbiter S-band quad antennas by the orbiter on-board computers was evaluated. The development and use of an extensive computer program to determine antenna switch position states as a function of time for various orbital activities is described. The selection of the optimum quad antenna element at any given time is based on the look angle to the appropriate Tracking Data Relay Satellite (TDRS). It is shown that a 2.4 second period is required for updating the S-band quad antenna switch state based on a maximum roll rate of 2 deg per second. The possibility of a variable update period is suggested since the 2 deg per second attitude rate is seldom encountered and would, for example, dictate approximately 248,000 on-board computer calculations during Reference Mission 2. The average number of antenna switch state changes was found to be in the range of 1,300 for Reference Mission 2