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The results of tests conducted on strip heaters intended for the Large Hadron Collider (LHC) are presented. The tests were performed on two locations on a 1.9-meter high gradient quadrupole model to study heater response times based on strip heater induced quenches and peak temperatures and quench velocities from spot heater induced quenches. The LHC interaction region is expected to be dependent on strip heaters for quench protection.

The design of the Fermilab high-gradient quadrupole superconducting magnet is presented. The mechanical design provides satisfactory coil support against mechanical disturbances in the body of the magnet. However, problems remain in the end regions of the magnets, where majority of the training quenches occur. The end transition region has been improved by extending the copper wedge further into the ends resulting in better mechanical support and higher adhesion between cable and end parts.

The design, production experience and experimental results of the initial 2 m quadrupole magnet models are presented. The quadrupole magnets are being designed and tested by the Lawrence Berkeley National Laboratory and the Fermi National Accelerator Laboratory for the LHC Interaction Region inner triplets. The magnets have a nominal gradient of 205 T/m in a 70 mm bore and are designed to operate in a superfluid helium environment at a temperature of 1.9 degrees Kelvin.

The Brookhaven National Laboratory, Lawrence Berkeley National Laboratory and Fermilab are jointly developing a high gradient quadrupole for the LHC interaction regions. The design involves a two-layer, cos(2theta) coil geometry incorporated in a 70 mm aperture operating in superfluid helium conditions. Magnetic, thermal and mechanical design developments for cooling, high field quality and maximum gradient exceeding 250 T/m are described.

Heat flow analyses were conducted on LHC interaction region quadrupoles to the boiling saturated He II. Stagnant pressurized He II has been the primary coolant for quadrupole magnets. The influence of cooling channel heights and cable surface heat flux on the magnet's thermal characteristics was then examined. Comparisons were also conducted on internally- and externally-arranged He II heat exchanger designs.

Fermilab is developing high gradient quadrupoles for applications in the Large Hadron Collider interaction regions at CERN. To gather information on ideal quadrupole designs, tests were conducted on a Tevatron low-Beta quadrupole cold mass. The quadrupole's temperature performance was compared to that of a mechanically-modified, heavily-instrumented version. The quadrupole exhibited excellent coil cooling and quench characteristics in superfluid helium conditions.

Complications regarding the fabrication of a graded cable splice in outer coils may be avoided by using a magnetic design for the LHC interaction region quadrupole. The approach, which maintains maximum gradients to over 235 T/m, involves the use of a closed iron, shims, strong preloaded collars and iron. Mechanical finite element analysis reveals a maximum gradient excitation and cooldown to 1.8 K.

We present an overview of the CDF End Plug Upgrade Project. The structure of the upgraded calorimeter and the design of the optical readout system is discussed. We describe the production of scintillating tile/fiber multi-tile assemblies (megatiles) and present the quality control results of megatiles produced for the CDF End Plug Upgrade Hadron Calorimeter. The sample of megatiles presented in this analysis corresponds to approximately 16,500 individual tile/fiber assemblies. We discuss the quality control requirements and present the distributions of the quantities measured during the QC process. The various contributions to the tile-to-tile light yield variations are isolated and discussed.

Field measurement of quadrupole magnets for the Large Hadron Collider's (LHC) interaction regions are reported and discussed.

Bird strike is a significant problem for the aviation industry, caused in part by the attractiveness of the grass surrounding airports to birds. Endophyte-infected grasses such as Avanex® have been shown to reduce bird populations at airports through the production of secondary metabolites. These metabolites are unpalatable to herbivorous, omnivorous and granivorous birds and are known to reduce insect densities, thereby making the sown areas less attractive to insectivorous birds. Raptors also provide a bird-strike threat which could be reduced by controlling mouse populations around airports. In this study, the effect of endophyte-infected seed on mouse feeding behaviour has been investigated. By performing a choice trial offering diets containing endophyte-infected and endophyte-free tall fescue seed, it was shown that endophyte-infected seed was less palatable to mice ( P < 0·001 in a 14-d trial). Furthermore, when diet positions were reversed, mouse feeding behaviour was modified to again select endophyte-free material ( P < 0·001 over a further 14 d). This result shows that endophyte-infected grasses could not only be used in the control of bird populations but they also have the potential to control mouse populations which in turn would decrease the number of raptors. This use of endophyte-infected grasses in areas surrounding airport runways shows great promise for the aviation industry. [ABSTRACT FROM AUTHOR]