Binary manipulation techniques are increasing in popularity. They support program transformations tailored toward certain program inputs, and these transformations have been shown to yield performance gains beyond the scope of static code optimizations without profile-directed feedback. They even deliver moderate gains in the presence of profile-guided optimizations. In addition, transformations can be performed on the entire executable, including library routines. This work focuses on program instrumentation, yet another application of binary manipulation. This paper reports preliminary results on generating partial data traces through dynamic binary rewriting. The contributions are threefold. First, a portable method for extracting precise data traces for partial executions of arbitrary applications is developed. Second, a set of hierarchical structures for compactly representing these accesses is developed. Third, an efficient online algorithm to detect regular accesses is introduced. These efforts are part of a larger project to counter the increasing gap between processor and main memory speeds by means of software optimization and hardware enhancements.

IN THE EVALUATION OF ODH, THE CALCULATION OF THE SPILL RATE FROM THE PRESSURIZED VESSEL IS THE CENTRAL TASK. THE ACCURACY OF THE ENGINEERING ESTIMATION BECOMES ONE OF THE SAFETY DESIGN ISSUES. THIS PAPER SUMMARIZES THE EQUATIONS FOR THE OXYGEN CONCENTRATION CALCULATION IN DIFFERENT CASES, AND DISCUSSES THE EQUATIONS FOR THE GAS RELEASE PROCESS CALCULATION BOTH FOR THE HIGH-PRESSURE GAS TANK AND THE LOW-TEMPERATURE LIQUID CONTAINER.

Several small and precise 90{degree}, 20-inch-radius bending and focusing magnet systems will be needed for the transport line of the Fermilab Electron Cooling Project to transport 4.36 MeV electrons. Originally, it was anticipated that these magnets would have a gradient index of {minus}1/2. To measure these magnets and complete achromatic bend modules, a well defined beam transport system was developed to determine the transfer matrix knowing the position and angle of several input and output beam rays passing through the magnet. The beam for this was a 12.5 keV proton beam that has the same magnetic rigidity as the electron beam in the final setup. The magnetic field is approximately 300 Gauss. For this purpose a high-brightness proton source was used and the beam collimated to give a low emittance ({approximately}10{sup {minus}8} m rad) pencil beam of {approximately}1 mm diameter with a current of {approximately}100 nA. Details of the system and results of measuring a magnet will be presented.

The design, construction, and bench testing of an X-band travelling-wave accelerating structure loaded with a permittivity=20 dielectric has been published recently by the Argonne Advanced Accelerator Group [1]. Here we describe a new program to build a test accelerator using this structure. The accelerator will be powered using high-power 11.424-GHz radiation available at the Magnicon Facility at the Naval Research Lab [2]. The magnicon is expected to provide up to 30 MW from each of two WR-90 output waveguide arms in pulses of up to 1-{micro}s duration, permitting tests of the dielectric-loaded X-band device at gradients of {approximately}40 MV/m. The use of higher power pulses (100-500 MW) eventually available at the output of an active pulse compressor [3] driven by the magnicon will permit gradients in excess of 100 MV/m to be achieved.

D0 and CDF have already started collecting data from p{bar p} collisions at the Tevatron with the Main Injector in operation and at {radical}s {approx} 2 TeV. A number of recently completed SUSY searches using data from Run I are discussed.

During the past year, the CDF Experiment has reported on a variety of results concerning QCD and electroweak studies, studies of the top quark, and searches for new phenomena. A sample of these results is presented here.

In this paper, we present a detailed analysis of the modes of a dielectric-loaded rectangular waveguide accelerating structure. In general, the acceleration field in a synchronous acceleration mode is non-uniform in the two transverse dimensions. However, we could use an array of these structures rotated alternatively by 90 degrees to get a focusing-defocusing force continuously as a simple FODO lattice, while maintaining uniform energy gain. The expressions of characteristic parameters such as R/Q, group velocity and attenuation constant are given. The longitudinal wake field experienced by a relativistic charged particle beam in the structure is also presented. These analytical results are also compared with numerical calculations using the MAFIA code suite demonstrating the validity of our analytic approach.

This Workshop was extremely useful in fleshing out many of the details related to the VLLC. For example, at the workshop it became very clear that the large machine could not provide high luminosity polarized beams at both the Z0 pole and at high energy, and it would be best to provide the Z0 factory function in the injector. In addition, the workshop identified a number of topics for further R and D. A list of some of these topics follows: What is the lower limit on {beta}{sub y}* in the high energy collider? What is a reasonable upper limit on the beam-beam parameter at 183 GeV? Is there a way to coalesce electron bunches at high energy to finesse the TMCI current limit at injection, allowing a smaller beam pipe aperture to be used? Can feedback systems be useful to combat the TMCI instability at injection? In the 45 GeV Z{sup 0} factory, are two rings essential? Are wigglers essential for polarization in the Z{sup 0} factory? How can polarization at high energies be optimized? What is the optimum method of pumping the long vacuum chamber sections? How much cost and power minimization is possible in the complete design? …

The effects of structural defects on the electrical activity of S doped GaN{sub x}As{sub 1-x} layers formed by S and N coimplantation in GaAs are reported. S and N ions were implanted to the depth of about 0.4 {micro}m. Electrochemical capacitance voltage measurements on samples annealed at 945 C for 10s show that in a thin (<0.1 {micro}m) surface layer the concentration of active shallow donors is almost an order of magnitude larger in S and N co-implanted samples than in samples implanted with S alone. The activation efficiency of S donors also shows a broad minimum at a depth of about 0.2 {micro}m below the surface. The results of these electrical measurements are correlated with the distribution of structural defects revealed by transmission electron microscopy (TEM). The TEM micrographs show that in addition to a band of dislocation loops commonly found in ion implanted GaAs, an additional band of small voids is observed in samples co-implanted with S and N. The location of this band correlates well with the region of reduced electrical activation of S donors, suggesting that formation of the voids through N accumulation results in a lower concentration of active, substitutional N atoms.

A five-watts G-M/J-T refrigerator was built and installed for the high-energy physics research at Brookhaven National Laboratory in 2001. A liquid helium target of 8.25 liters was required for an experiment in the proton beam line at the Alternating Gradient Synchrotron (AGS) of BNL. The large radiation heat load towards the target requires a five-watts refrigerator at 4.2 K to support a liquid helium flask of 0.2 meter in diameter and 0.3 meter in length which is made of Mylar film of 0.35 mm in thickness. The liquid helium flask is thermally exposed to the vacuum windows that are also made of 0.35 mm thickness Mylar film at room temperature. The refrigerator uses a two-stage Gifford-McMahon cryocooler for precooling the Joule-Thomson circuit that consists of five Linde-type heat exchangers. A mass flow rate of 0.8 {approx} 1.0 grams per second at 17.7 atm is applied to the refrigerator cold box. The two-phase helium flows between the liquid target and liquid/gas separator by means of thermosyphon. The paper presents the system design as well as the test results including the control of thermal oscillation.

Fermilab and other DOE high energy physics laboratories are studying the possibility of a Very Large Hadron Collider (VLHC) for operation in the post-LHC era. The current VLHC design [1] foresees a 2-staged approach, where the second stage (referred to as VLHC-2) has a proton energy up to 100 TeV at a peak luminosity of 2{center_dot}10{sup 34} cm{sup {minus}2} sec{sup {minus}1}. The protons are guided through a large 233 km circumference ring with 10 T bending magnets using Nb{sub 3}Sn superconductor at 5 K. The synchrotron radiation (SR) power emitted by the beam in such a machine is {approx}5 W/m/beam [1]. However, other VLHC scenarios (e.g. [2]) with smaller rings and higher luminosity result in SR power levels exceeding this value, reaching 10 or even 20 W/m/beam. Intercepting and removing this power in a cryogenic environment is a major challenge. In this paper a discussion of SR in the VLHC-2, and various approaches to the issue, are presented. One possibility is the use of a beam screen (BS) to intercept the synchrotron radiation power. The BS operating temperature is chosen to balance thermodynamic efficiency, cryogenic-, vacuum-, beam-stability- and magnet-aperture issues. Another approach is to intercept the radiation in discrete points …

The status of QCD studies at the Fermilab Tevatron are discussed. Specifically, the measurements of inclusive jet cross sections from the CDF and D0 collaborations are compared to theoretical predictions. New measurements in the forward rapidity regions are described and multijet results are discussed.

The preconceptual design of an S-band photo-injector system for a Next Linear Collider (NLC) Engineering Test Facility (ETF) at Fermi National Accelerator Laboratory (FNAL) has been completed. A photo-cathode gun will deliver a range of bunch charges up to 4 nC at around 190 MeV. The projected performance is 2.5 {pi} mm-mrad rms normalized transverse emittance at 1 nC and 6.7 {pi} mm-mrad at 3.6 nC bunch charge, for 0.5 mm rms radius spherical bunches with an energy spread of less than 0.1%. We describe the proposed beamline and the performance achieved in end-to-end simulations.

A liquid helium target for the high-energy physics was built and installed in the proton beam line at the Alternate Gradient Synchrotron of Brookhaven National Laboratory in 2001. The target flask has a liquid volume of 8.25 liters and is made of thin Mylar film. A G-M/J-T cryocooler of five-watts at 4.2K was used to produce liquid helium and refrigerate the target. A thermosyphon circuit for the target was connected to the J-T circuit by a liquid/gas separator. Because of the large heat load to the target and its long transfer lines, thermal oscillations were observed during the system tests. To eliminate the oscillation, a series of tests and analyses were carried out. This paper describes the phenomena and provides the understanding of the thermal oscillations in the target system.