Comparative experiments using high energy (10 MeV) electrons and test reactor neutrons have been undertaken to understand the role that primary damage state has on hardening (embrittlement) induced by irradiation at 300 C. Electrons produce displacement damage primarily by low energy atomic recoils, while fast neutrons produce displacements from considerably higher energy recoils. Comparison of changes resulting from neutron irradiation, in which nascent point defect clusters can form in dense cascades, with electron irradiation, where cascade formation is minimized, can provide insight into the role that the in-cascade point defect clusters have on the mechanisms of embrittlement. Tensile property changes induced by 10 MeV electrons or test reactor neutron irradiations of unalloyed iron and an Fe-O.9 wt.% Cu-1.0 wt.% Mn alloy were examined in the damage range of 9.0 x 10{sup {minus}5} dpa to 1.5 x 10{sup {minus}2} dpa. The results show the ternary alloy experienced substantially greater embrittlement in both the electron and neutron irradiate samples relative to unalloyed iron. Despite their disparate nature of defect production similar embrittlement trends with increasing radiation damage were observed for electrons and neutrons in both the ternary and unalloyed iron.

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Laser modulated scattering (LMS) is introduced as a non-destructive evaluation tool for defect inspection and characterization of optical surfaces and thin film coatings. This technique is a scatter sensitive version of the well-known photothermal microscopy (PTM) technique. It allows simultaneous measurement of the DC and AC scattering signals of a probe laser beam from an optical surface. By comparison between the DC and AC scattering signals, one can differentiate absorptive defects from non-absorptive ones. This paper describes the principle of the LMS technique and the experimental setup, and illustrates examples on using LMS as a tool for nondestructive evaluation of high quality optics.

We present the latest results from the CDF experiment at the Tevatron Collider in p{bar p} collisions at {radical}s = 1.8 TeV. The large data sample collected during Run 1, from 1992 until 1995, allows measurements in many domains of high-energy physics. Here, we report on the first measurement of sin(2{beta}), a CP violation parameter, and on an improved measurement of the top quark cross section. We also report on searches for the so-far elusive Higgs boson, and for SUSY, through searches for direct production of top and bottom scalar quarks. Finally, we outline the prospects for the physics during the upcoming Run 2, ready to start in the upcoming year 2000.

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Conventional electroactive stack components in thermal batteries are constructed from pressed-powder parts. These include the anode, separator, and cathode pellets (discs). Pressing parts that are less than 0.010 inch thick is difficult. The use of plasma spray to deposit thin CoS{sub 2} cathode films onto a stainless steel substrate was examined as an alternative to pressed-powder cathodes. The plasma-sprayed electrodes were tested in single cells under isothermal conditions and constant-current discharge over a temperature range of 400 C to 550 C using standard LiSi anodes and separators based on the LiCl-KCl eutectic. Similar tests were conducted with cells built with conventional pressed-powder cathodes, which were tested under the same conditions for comparative purposes. This paper presents the results of those tests.

We study the feasibility of a precise measurement of the mass of a 120 GeV MSM Higgs boson through direct reconstruction of ZH {yields} q{bar q}H events that would be achieved in a future e{sup +}e{sup -} linear collider operating at a center-of-mass energy of 500 GeV. Much effort has been put in a ''realistic simulation'' by including irreducible+reducible backgrounds, realistic detector effects and reconstruction procedures and sophisticated analysis tools involving Neural Networks and kinematical fitting. As a result, the Higgs mass is determined with a statistical accuracy of 50 MeV and the Z-Higgs Yukawa coupling measured to 0.7%, assuming 500 fb{sup -1} of integrated luminosity.

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Thin films of complex perovskites have a number of potentially important applications. Of major scientific and practical concern is the scaling of properties as film dimensions are reduced. This paper describes a satisfactory relationship between bulk and thin film dielectric properties of (Ba,Sr)TiO{sub 3}. Relative contributions of strain, A:B cation stoichiometry, and interface are separated to explain temperature dependent dielectric behavior.

High angular resolution electron channeling X-ray spectroscopy (HARECXS) was examined as a practical tool to locate lattice-ions in spinel crystals. The orientation dependent intensity distribution of emitted X-rays obtained by HARECXS is so sensitive to lattice-ion configuration in the illuminated areas that the occupation probabilities on specific positions in the crystal lattice can be determined accurately through comparison with the theoretical rocking curves. HARECXS measurements have revealed partially disordered cation arrangement in MgO{center_dot}nAl{sub 2}O{sub 3} with n = 1.0 and 2.4. Most Al{sup 3+} lattice-ions occupy the octahedral (VIII) sites, while Mg{sup 2} lattice-ions reside on both the tetrahedral (IV) and the octahedral (VIII) sites. The structural vacancies are enriched in the IV-sites. Further evacuation of cations from the IV-sites to the VIII-sites is recognized in a disordering process induced by irradiation with 1 MeV Ne{sup +} ions up to 8.9 dpa at 870 K.

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Beam gauges have been used in the last decade or so for measuring the internal azimuthal compressive coil stresses in superconducting magnets. In early model Large Hadron Collider Interaction Region (LHC IR) quadrupoles tested at Fermilab, the beam gauges indicated excessively high amounts of inner and outer coil prestress during the collaring process, inconsistent with the coil size and modulus data. In response to these measurements, a simple mechanics based quantitative understanding of different factors affecting beam gauges has been developed. A finite element model with contact elements and non-linear material behavior, confirmed with experimental results, was developed. The results indicate that a small plastic deformation of either the beam or the backing plate can cause significant errors in the measured stress values. The effect of variations in coil modulus and support boundary conditions on beam gauge performance are also discussed.

The trilinear couplings appear as the three gauge boson vertices and can be measured by studying the gauge boson pair production processes. The measurement of the coupling parameters is one of the few remaining crucial tests of the Standard Model. D0 has studied W{gamma}, Z{gamma}, WW, and WZ production and found no evidence of anomalous production. In this paper we review all the current results from D0 data.

Zirconolite is one of the major host phases for actinides in various wasteforms for immobilizing high level radioactive waste (HLW). Over time, zirconolite's crystalline matrix is damaged by {alpha}-particles and energetic recoil nuclei recoil resulting from {alpha}-decay events. The cumulative damage caused by these particles results in amorphization. Data from natural zirconolites suggest that radiation damage anneals over geologic time and is dependant on the thermal history of the material. Proposed HLW containment strategies rely on both a suitable wasteform and geologic isolation. Depending on the waste loading, depth of burial, and the repository-specific geothermal gradient, burial could result in a wasteform being exposed to temperatures of between 100--450 C. Consequently, it is important to assess the effect of temperature on radiation damage in synthetic zirconolite. Zirconolite containing wasteforms are likely to be hot pressed at or below 1,473 K (1,200 C) and/or sintered at or below 1,623 K (1,350 C). Zirconolite fabricated at temperatures below 1,523 K (1,250 C) contains many stacking faults. As there have been various attempts to link radiation resistance to structure, the authors decided it was also pertinent to assess the role of stacking faults in radiation resistance. In this study, they simulate {alpha}-decay damage …

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Metalorganic chemical vapor deposition was used to synthesize epitaxial Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}{minus}PbTiO{sub 3} films on SrTiO{sub 3} and SrRuO{sub 3}/SrTiO{sub 3} substrates, using solid Mg(DPM){sub 2} as the Mg precursor. Depositing conditions have been identified under which phase-pure perovskite PMN-PT may be grown. In contrast, in lead-poor environments, an additional second phases of a disordered magnesium-niobium oxide has tentatively been identified. X-ray diffraction and selected area electron diffraction indicate a cube-on-cube orientation relationship between film and substrate, with a (001) rocking curve width of 0.1{degree}, and in-plane mosaic of 0.8{degree}. The rms surface roughness of a 200nm thick PMN film on SrTiO{sub 3} was 2 to 3 nm as measured by scanned probe microscopy. The zero-bias dielectric constant and loss measured at room temperature and 10 kHz for a 350 nm thick pure PMN film on SrRuO{sub 3}/SrTiO{sub 3} were 1100 and 2%, respectively. Small-signal permittivity ranged from 900 to 1400 depending on deposition conditions and Ti content; low values for the dielectric loss between 1 and 3% were determined for all specimens. Here the authors report on growth conditions and the initial structural and dielectric characterization of these samples.