The stability of empty resonators (or cold cavities) has been widely studied, and is well understood. Here we consider the stability of symmetric resonator systems when there is a free-electron laser (FEL) interaction present within the cavity. We first construct a linear thick-lens model of the FEL and analytically study the dependence of resonator stability on its geometry. Next, we employ a nonlinear, three-dimensional FEL oscillator code to study the dependence of FEL performance on the cavity configuration. The analytic and numerical approaches are compared and it is shown that they agree quite well. It is found that the region of stability is shifted toward longer cavities, and beyond the concentric configuration. Between the confocal and the concentric configurations, where the empty-resonator analysis predicts stability, there now appear regions of instability. We find that operation near the concentric configuration is preferable, and operation very near the confocal should be avoided.

A copy of a newspaper article pertaining to the military's anti-gay and lesbian servicemen policies and how the policies have been challenged by the Lambda Legal Defense and Education Fund.

The Advanced Photon Source (APS), which is currently under construction as a national user facility at Argonne National Laboratory is a third-generation synchrotron x-ray source, one of only three in the world. It is expected to produce x-rays that are 10,000 times brighter than any currently produced elsewhere for use in research in a wide range of scientific areas. Users from industry, national laboratories, universities, and business will be able to come to the APS to conduct research either as members of Collaborative Access Teams (CATS) or as Independent Investigators. Principal users will be members of CATS, which will be building and operating all of the beamlines present in the first phase of APS beamline development. The first set of CATs has been selected through a competitive proposal process involving peer scientific review, thorough technical evaluation, and significant management oversight by the APS. This document is a compilation of posters presented at the Fifth Users Meeting for the Advanced Photon Source, held at Argonne National Laboratory on October 14--15, 1992. All CATs whose scientific cases were approved by the APS Proposal Evaluation Board are included. In addition, this document contains a poster from the Center for Synchrotron Radiation and Research …

This paper describes the development of an RF cavity design for the proposed PEP-II asymmetric B factory. The high luminosity required of PEP-II provides challenges in the design of the RF cavities, most notably in the reduced higher-order mode (HOM) impedances that must be attained and in the power that must be dissipated in the cavity walls. This paper outlines the goals set in these regards, describes how the cavity has been developed to meet them, and presents the results of measurements on a low-power test model built to verify the HOM damping scheme.

Photoemission from Cu mirror at a laser fluence of 10[sup 11] W/cm[sup 2], 300 fs, pulse is investigated for various angles of incidence, intensities and polarizations. Electron emission is enhanced by [approximately] 20 from s to p polarization and by 4 on changing the angle of incidence from 0 to 73 degree.

We compare the ratio of the strong coupling [alpha][sub s] measured in Z[sup 0] [yields] b[bar b] events to that measured in Z[sup 0] [yields] q[bar q](q=u,d,s,c) in the SLD experiment at SLAC. Z[sup 0] [yields] b[bar b] events are identified with the aid of a precision silicon vertex detector by requiring that at least three charged tracks pass more than 3.0[sigma] from the Z[sup 0] decay vertex. This method has an estimated efficiency of 54% with a purity of 71%. Jets are identified and counted by clustering charged tracks according to the JADE algorithm. By comparing the 3-jet fraction in tagged events to that in all hadronic events, we extract a preliminary result of [alpha][sub s](b)/[alpha][sub s](udsc) = 1.18 [plus minus] 0.11(stat) [plus minus] 0.05(sys).

Differential electron emission is studied for 50--500 keV H[sup +] and H atom impact on helium. Using the first Born formulation, it is shown that projectile electron-target electron interactions are expected to dominate the differential cross sections for low energy target electron emission induced by fast neutral projectile impact on any target. Measurements of the 15[degrees] electron emission were made in order to investigate this prediction. For low impact energies, a constant ratio between the hydrogen atom and proton impact cross sections was found for emitted electron velocities less than half the projectile velocity, V[sub p] But as the collision energy increased, for electron velocities less than 0.25 V[sub p], the cross section ratio increased as the emitted electron velocity decreased. This is interpreted as a signature of projectile electron-target electron interactions becoming dominant for distant collisions between neutral particles.

One result of the 1991 B Factory Workshop at SLAC was the definition of a software benchmark project: a user-friendly data browsing tool called a tupleviewer''. The tupleviewer is a program which interactively displays 1-D and 2-D graphical plots from data stored as n-tuples. A set of rules define the minimum requirements for the tupleviewer, but the choices for platform, programming language, window system, graphics package and GUI development system are left open. The purpose of this project is to provide an arena in which to compare these open choices, as well as to provide a training exercise. The results of these efforts, including the experiences of the developers and comparisons between the projects are reported. In particular, comparisons are reported between the various GUI tool kits used.

The left-right cross section asymmetry for Z boson production in e[sup +]e[sup -] annihilation (A[sub LR]) has been measured at E[sub cm] = 91.55 GeV with the SLD detector at the SLAC Linear Collider (SLC) using a longitudinally polarized electron beam. The electron polarization was continually monitored with a Compton scattering polarimeter, and was typically 22%. We have accumulated a sample of [approximately]10,200 Z events. We find that A[sup LR] = 0.100 [plus minus] 0.044 [plus minus] 0.003 where the first error is statistical and the second is systematic. From this measurement, we determine the weak mixing angle defined at the Z boson pole to be sin[sup 2][theta](lept/w) = 0.2378 [plus minus] 0.0056.

This paper reviews a number of programs funded through the Engineered Tribological Interfaces (ETI) Task area of the Tribology Program that utilize energetic beams of atoms to enhance the mechanical and microstructural properties of near-surface regions to improve the tribological performance of critical components. The processes used in these programs include techniques based on chemical vapor deposition, physical vapor deposition, and ion implantation. A common feature of these techniques is their ability to produce dense and adherent modified surfaces without need for subsequent grinding/polishing treatments. Another feature of these techniques is their ability to introduce a wide range of elements into near-surface regions.

A large silicon strip tracking detector is planned for the upgrade of the D0 experiment at Fermilab. This detector is designed to gag secondary vertices, to measure the momenta of charged particles and to operate in the high rate environment of the upgraded Tevatron. Details of the detector design are presented here.

The reconstruction of high-angle twist grain boundaries on the four densest atomic planes in gold are investigated using the recently developed method of grand-canonical simulated quenching. It is found that the grain boundaries on the two densest planes, (111) and (100), do not reconstruct, while those on the (110) and (113) planes do.

Dissolution rates for air-oxidized spent fuel were measured in flowthrough tests. Results from two types of specimens, separated grains and multigrain particles, both in oxidized (U[sub 4]O[sub 9+x]) and unoxidized (UO[sub 2]) conditions indicated only minor effects of oxidation on the surface-area-normalized rates. Similar results were obtained for unirradiated specimens in three different oxidation states (UO[sub 2], U[sub 3]O[sub 7], and U[sub 3]O[sub 8]). These observations have important practical implications for disposal of spent fuel in a geologic repository as well as implications regarding the oxidative dissolution mechanism of UO[sub 2] fuel.

We study the effects of virtual leptoquark exchange on charged current and neutral current process at HERA, on di-lepton production at the Tevatron, and on quark pair production at LEP II. We present the areas of parameter space that can be excluded at these colliders by searching for deviations from Standard Model expectations.

An analysis of the W [yields] l[nu] events, l=e,[mu], yields a jet multiplicity distribution. Data selection and background are presented. The data are shown to be in good agreement with the VECBOS Monte Carlo which generates W [yields] l[nu] plus n jets by a leading order QCD calculation (n=0[divided by]4).

Kinematic properties of four-jet events in p[bar p] collisions at [radical]s = 1.8 TeV are compared with the predictions of leading order quantum chromodynamics. We place an upper limit on the double parton scattering cross of [sigma][sub DP] < 120 nb (95% C.L.) for partons with transverse momenta greater than 18 GeV/c. Defining the effective cross section [sigma][sub eff] through the equation of [sigma][sub eff] = [sigma][sub DP] = [sigma][sub dijet]/([sup 2]/[sigma][sub eff]), where [sigma][sub dijet] is the cross section for two-jets events, the limit [sigma][sub eff] > 3.9 mb (95% C.L.) is also placed. Implications for physics at the SSC ([radical]s = 40 TeV) are discussed.

We review prospects for top discovery in the current 1992 CDF run, focusing on the inclusive electron and muon channels. In the standard model, [approximately] 37% of t[bar t] events contain a high P[sub T] electron or muon. In particular, B tagging through soft leptons and secondary vertices are discussed. Expected signal to background and prospects for the current CDF 1992 run are given.

We discussed the use of renormalization counterterms to restore the chiral gauge symmetry in a lattice theory of Wilson fermions. We show that a large class of counterterms can be implemented automatically by making a simple modification to the fermion determinant.

The angular dependence of the magnetoresistance was measured on the same single crystal of a YBa[sub 2]Cu[sub 3]O[sub 7-[delta]] prepared initially with a superconducting transition temperature of 93.0K and then annealed to obtain a transition temperature of 56.9K. A second oxygen deficient sample was produced with a transition temperature 57.0K and nearly identical transport characteristics. Twin boundary pinning superimposed on flux flow behavior was observed in both the 56.9K and 93.0K states for magnetic field rotation in ab plane. For magnetic field rotations off the c axis we observe twin boundary pinning only for the nearly stoichiometric state. We find the broadening of the resistive transition in magnetic field (H [parallel] c) to occur over a much larger interval of reduced temperature in the deoxygenated state. The enhanced broadening of the resistive transition in magnetic field and absence of twin boundary pinning may indicate that the vortex system is two dimensional and in general, defects are rendered ineffective in pinning due to the absence of three dimensional collective elastic effects.

This article consists of three parts. In part one we review the present status of dense nuclear matter calculations, and introduce a representative collection of realistic nuclear equations of state which are derived for different assumptions about the physical behavior of dense matter (baryon population, pion condensation,.possible transition of baryon matter to quark matter). In part two we review recently performed non-rotating and rotating compact star calculations performed for these equations of state. The minimum stable rotational periods of compact stars, whose knowledge is of decisive importance for the interpretation of rapidly rotating pulsars, axe determined. For this purpose two different limits on stable rotation are studied: rotation at the general relativistic Kepler period (below which mass shedding at the star's equator sets in), and, secondly, rotation at the gravitational radiation-reaction instability (at which emission of gravitational waves set in which slows the star down). Part three of this article deals with the properties of hypothetical strange stars. Specifically we investigate the amount of nuclear solid crust that can be carried by a rotating strange star, and answer the question whether such objects can give rise to the observed phenomena of pulsar glitches, which is at the present time the …

This document contains the inventories (70,000 cubic meters) and generation rates (7,700 cubic meters/ year) of low-level mixed wastes for the U.S. DOE. The twelve sites with the most significant processing needs are Fernald, Hanford, K-25, Idaho National Engineering Laboratory (INEL), Lawrence Livermore National Laboratory, Los Alamos National Laboratory (LANL), Oak Ridge National Laboratory (ORNL), Padacuh Gaseous Diffusion Plant, Savannah River Site (SRS), and Y-12 plant. The largest inventories are located at INEL, Y-12, SRS, and K-25. The largest generation rates are located at INEL, Y-12, and SRS.

Recent developments in the use of interlayers to tailor the Schottky barrier height (SBH) at a metal/GaAs interface are discussed. The goal has been to gain control of band bending in the interfacial region by modifying both the interface Fermi energy and the charge density in the depletion region. The approach has been to grow both the interlayer and the metal overlayer under ultrahigh vacuum conditions by molecular beam epitaxy, and then to determine the chemistry of interface formation, structure, and band bending by x-ray photoelectron spectroscopy and diffraction and by low-energy electron diffraction. The interface Fermi energy can be changed from the usual midgap value of 0.7--0.8 eV relative to the band edge by the use of epitaxial transition metal aluminide (TMA) overlayers such as NiAl. The unique chemistry of interface formation between this intermetallic compound and GaAs pins the Fermi level [approximately]0.3--0.4 eV above the valence band maximum, and results in a SBH of [approximately]1 eV. The SBH can be increased to [approximately]1.2 eV by the use of a wide bandgap interlayer such as AlAs. The charge density in the depletion region can be changed by growing an n[sup +]-type group IV interlayer between the TMA overlayer and …

A laboratory procedure is given for demonstrating, for students at high school level or above, the difference between the electrical conductivity of metals and ceramics.

In January 1992, Argonne National Laboratory East, Environmental and Waste Management Program, learned that a chemical material used for testing of all HEPA filters at the primary source, Flanders Filter, Inc. in Washington, NC, was considered a hazardous chemical by Washington State Dangerous Waste Regulations. These regulations are under the jurisdiction of the Washington Administration Code, Chapter 173-303, and therefore directly under impact the Hanford Site Solid Waste Acceptance Criteria. Dioctyl Phthalate, DOP'' as it is referred to in chemical abbreviation form, is added in small test quantities at the factory, at three Department of Energy (DOE) operated HEPA filter test facilities, and in the installed duct work at various operating laboratories or production facilities. When small amounts of radioactivity are added to the filter media in operation, the result is a mixed waste. This definition would normally only develop in the state of Washington since their acceptance criteria is ten times more stringent then the US Environmental Protection Agencys' (US EPA). Methods of Processing will be discussed, which will include detoxification, physical separation, heat and vacuum separation, and compaction. The economic impact of a mixed waste definition in the State of Washington, and an Low Level Waste (LLW) definition …