We propose Compton scattering of a short pulse visible laser beam by a low energy (but relativistic) electron beam at a right angle for generation of femtosecond x-rays. Simple analysis to determine the qualitative and quantitative characteristics of the x-ray pulse is presented.

A review of recent developments in the quantum differential calculus. The quantum group GL[sub q](n) is treated by considering it as a particular quantum space. Functions on SL[sub q] (n) are defined as a subclass of functions on GL[sub q](n). The case of SO[sub q](n) is also briefly considered. These notes cover part of a lecture given at the XIX International Conference on Group Theoretic Methods in Physics, Salamanca, Spain 1992.

Spin physics activities at medium and high energies became significantly active when polarized targets and polarized beams became accessible for hadron-hadron scattering experiments. My overview of spin physics will be inclined to the study of strong interaction using facilities at Argonne ZGS, Brookhaven AGS (including RHIC), CERN, Fermilab, LAMPF, an SATURNE. In 1960 accelerator physicists had already been convinced that the ZGS could be unique in accelerating a polarized beam; polarized beams were being accelerated through linear accelerators elsewhere at that time. However, there was much concern about going ahead with the construction of a polarized beam because (i) the source intensity was not high enough to accelerate in the accelerator, (ii) the use of the accelerator would be limited to only polarized-beam physics, that is, proton-proton interaction, and (iii) p-p elastic scattering was not the most popular topic in high-energy physics. In fact, within spin physics, [pi]-nucleon physics looked attractive, since the determination of spin and parity of possible [pi]p resonances attracted much attention. To proceed we needed more data beside total cross sections and elastic differential cross sections; measurements of polarization and other parameters were urgently needed. Polarization measurements had traditionally been performed by analyzing the spin of …

The D0 Experiment is a new, large multipurpose experiment at the Tevatron Proton-Antiproton Collider at the Fermi National Accelerator Laboratory. From the analysis of data taken during August--October, 1992, a selection of preliminary physics results will be given on inclusive jet production, direct photon production, the production and decay properties of the W and Z bosons, the search for the top quark in the dilepton and lepton + jets channels, B physics and searches for new particles.

The fact that experimental accuracy is finite makes the measurement of particle positions and velocities non-local and often non- commutative even in a scale invariant theory. Applied to electromagnetic and gravitational phenomena, we argue that this leads to a relativistic action at a distance theory in which fields'' are simple a quasi-local interpolating concept extrapolated from macroscopic conservation laws. We sketch how this analysis could lead to classical field equations as a macroscopic approximation to relativistic quantum mechanics, but do not construct a formal proof.

We calculate hadron spectrum of quantum chromodynamics without dynamical fermions on a 32[sup 3] [times] 64 lattice volume at [beta] = 6.5. Using two different wall sources of staggered fermion whose mass is 0.01, 0.005 and 0.0025 under the background gauge configurations, we extract local light hadron masses and the [triangle] masses and compare these hadron masses with those from experiments. The numerical simulation is executed on the Intel Touchstone Delta computer. We employ multihit metropolis algorithm with over-relaxation method steps to update gauge field configuration and gauge field configuration are collected at every 1000 sweeps. After the gauge field configuration is fixed to Coulomb gauge, the conjugate gradient method is used for Dirac matrix inversion.

The temperature dependence of amorphization dose for zircon under 1.5 MeV Kr ion irradiation has been investigated using the ANL HVEM-Tandem Facility. Three regimes were observed in the amorphization dose-temperature curve. In the first regime (15 to 300 K), the critical amorphization dose increased from 3.06 to 4.5 ions/nm[sup 2]. In the second regime (300 to 473 K), there is little change in the amorphizationdose. In the third regime (> 473 K), the amorphization dose increased exponentially to 8.3 ions/nm[sup 2] at 913 K. This temperature dependence of amorphization dose can be described by two processes with different activation energies (0.018 and 0.31 eV respectively) which are attributed to close pair recombination in the cascades at low temperatures and radiation-enhanced epitaxial recrystallization at higher temperatures. The upper temperature limit for amorphization of zircon is estimated to be 1100 K. The ion-mass dependence of the amorphization dose (in dpa) has also been discussed in terms of the energy to recoils based on data obtained from He, Ne, Ar, Kr, Xe irradiations and a [sup 238]Pu-doped sample.

[sup 63]Cu and [sup 65]Cu NMR spectra from cluster-assembled nanophase copper with an average grain size between 5 and 10mn show a broadened peak, at the normal Knight-shifted frequency for copper meta which arises from only the central 1/2 to -1/2 transition. A very broad background is observed on either side of that peak. Some samples exhibit a second broad peak at a position normally associated with non-metallic copper. Pulsed NMR measurements of the central peak show that virtually all the copper signals are significantly broadened and have a spin-spin relaxation time longer than larger grained copper samples. Line shape measurements, using spin echoes, as a function of delay between rf excitation and measurement show there are a number of copper sites with longer relaxation times which have a significantly larger broadening. Those sites are tentatively identified as being at or near a grain boundary or free surface. A small orientation effect is observed indicating an anisotropy within the samples. An isochronal anneal of one sample showed significant, but not complete, line narrowing after an anneal at 450C consistent with other nanophase metals which show grain growth above 40--50% of the melting temperature.

Recent studies have identified a number of critical technologies that are essential to the nation's defense, economic competitiveness, energy independence, and betterment of public health. The National Critical Technologies Panel (NCTP) has identified the following critical technology areas: Aeronautics and Surface Transportation; Biotechnology and Life Sciences; Energy and Environment; Information and Communications; Manufacturing; and Materials. Sponsored by the Department of Energy's Office of Energy Research (OER), the Critical Technologies Research Workshop was held in May 1992. Approximately 100 scientists, engineers, and managers from the national laboratories, industry, academia, and govemment participated. The objective of the Berkeley Workshop was to advance the role of the DOE multiprogram energy laboratories in critical technologies research by describing, defining, and illustrating research areas, opportunities, resources, and key decisions necessary to achieve national research goals. An agenda was developed that looked at DOE's capabilities and options for research in critical technologies and provided a forum for industry, academia, govemment, and the national laboratories to address: Critical technology research needs; existing research activities and resources; capabilities of the national laboratories; and opportunities for national laboratories, industries, and universities. The Workshop included plenary sessions in which presentations by technology and policy leaders set the context for further …

We describe current and future Polarized Light Sources at SLAC for use with photocathode electron guns to produce polarized electron beams. The SLAC experiments SLD and E142 are considered, and are used to define the required parameters for the Polarized Light Sources.

The D0 calorimeter trigger system consists of many levels to make physics motivated trigger decisions. The Level-1 trigger uses hardware techniques to reduce the trigger rate from [approximately] 100kHz to 200Hz. It forms sums of electromagnetic and hadronic energy, globally and in towers, along with finding the missing transverse energy. A minimum energy is set on these energy sums to pass the event. The Level-2 trigger is a set of software filters, operating in a parallel-processing microvax farm which further reduces the trigger rate to a few Hertz. These filters will reject events which lack electron candidates, jet candidates, or missing transverse energy in the event. The performance of these triggers during the early running of the D0 detector will also be discussed.

A brief overview of the status of lattice QCD is given, with emphasis on topics relevant to phenomenology. The calculation of the light quark spectrum, the lattice prediction of [alpha] [sub [ovr MS]] (M [sub Z]), and the calculation of f[sub B] are discussed. 3 figs., 3 tabs., 40 refs.

Single crystal silicon has been the material of choice for x-ray monochromators for the past several decades. However, the need for suitable monochromators to handle the high heat load of the next generation synchrotron x-ray beams on the one hand and the rapid and on-going advances in synthetic diamond technology on the other make a compelling case for the consideration of a diamond mollochromator system. In this Paper, we consider various aspects, advantage and disadvantages, and promises and pitfalls of such a system and evaluate the comparative an monochromator subjected to the high heat load of the most powerful x-ray beam that will become available in the next few years. The results of experiments performed to evaluate the diffraction properties of a currently available synthetic single crystal diamond are also presented. Fabrication of diamond-based monochromator is within present technical means.

A remarkable degree of consistency of experimental results from tokamaks throughout the world has developed with regard to the phenomenology of the transition from L-mode to H-mode confinement in tokamaks. The transition is initiated in a narrow layer at the plasma periphery where density fluctuations are suppressed and steep gradients of temperature and density form in a region with large first and second radial derivatives in the [upsilon][sub E][sup [yields]] = (E [times] B)/B[sup 2] flow velocity. These results are qualitatively consistent with theories which predict suppression of fluctuations by shear or curvature in [upsilon]E. The required [upsilon]E flow is generated very rapidly when the magnitude of the heating power or of an externally imposed radial current exceed threshold values and several theoretical models have been developed to explain the observed changes in the [upsilon]E flow. After the transition occurs, the altered boundary conditions enable the development of improved confinement in the plasma interior on a confinement time scale. The resulting H-mode discharge has typically twice the confinement of L-mode discharges and regimes of further improved confinement have been obtained in some H-mode scenarios.

I am honored to be invited to give a talk on this occasion to celebrate Martin Perl's 65th birthday. John Jaros, the organizer of this occasion, wanted me to recollect several things, especially: what motivated me to write my 1971 Physical Review paper on the heavy lepton entitled Decay Correlations of Heavy Lepton in e[sup minus] + e[sup +] = [ell][sup -] + [ell]+;'' why did I think of muon-electron coincidence; and what were the contributions of Thacker and Sakurai. In this paper I answer his requests and add something else later.

We have used a novel bolometric technique and a resonant technique to obtain accurate submillimeter and microwave residual loss data for epitaxial thin films of YBa[sub 2]Cu[sub 3]O[sub 7], Tl[sub 2]Ca[sub 2]Ba[sub 2]Cu[sub 3]O[sub 10] and Tl[sub 2]CaBa[sub 2]Cu[sub 2]O[sub 8]. For all films we obtain good agreement between the submillimeter and microwave data, with the residual losses in both the Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O films scaling approximately as frequency squared below [approximately] 1 THz. We are able to fit the losses in the Y-Ba-Cu-O films to a two fluid and a weakly coupled grain model for the a-b planeconductivity, in good agreement with results from a Kramers-Kronig analysis of the loss data.

Measurements of hadronic [tau] decays to states containing at least one strange meson are reviewed. New results are presented from a self-consistent analysis of one-prong decays including kaons and from a study of the kaon content in three-prong decays. First observations of the resonance contribution to the strange axial-vector channel are reported. The findings are compared to model predictions of K[sub 1] mixing and interference in [tau] decay.

We provide a preview of the physics issues which could be addressed with intense beams of pions in the 1--2 GeV/c region. These include: the exploitation of the ([pi][sup +], K[sup +]) associated production reaction on proton and nuclear targets for high resolution studies of hypernuclear structure and decays, as well as [Lambda]-proton scattering, the use of pion reactions with hydrogen or deuterium targets to provide tagged [eta] beams for studies of rare decays, precision studies of baryon resonances which couple to the [pi]N system, and the exploration of pion elastic, inelastic, and charge exchange reactions above the (3,3)-resonance as a tool for the study of nuclear structure.

We present a thermodynamic model of solid-state amorphization based on a generalization of the well-known Lindemann criterion. The original Lindemann criterion proposes that melting occurs when the root-mean-square amplitude of thermal displacement exceeds a critical value. This criterion can be generalized to include solid-state amorphization by taking into account the static displacements. In an effort to verify the generalized melting criterion, we have performed molecular dynamics simulations of radiation-induced amorphization in NiZr, NiZr[sub 2], NiTi and FeTi using embedded-atom potentials. The average shear elastic constant G was calculated as a function of the total mean-square atomic displacement following random atom-exchanges and introduction of Frenkel pairs. Results provide strong support for the generalized melting criterion.

A new run has begun at the Tevatron Collider, and two detectors, CDF and D0, have started taking data. After a short review of the situation of the top search in both the single and dilepton channel, we present the expectations for the near and far future. There have already been accelerator and detector upgrades, and more are to come. Important improvements are also expected from new analysis tools.

A significant enhancement of the in-field J[sub c] of Ag-clad (Bi,Pb)-Sr-Ca-Cu-0 (BPSCCO:2223) wires has been achieved using a controlled melt procedure. The greatly reduced weak linking has resulted in an extended plateau regime in the J[sub c]-H curve. J[sub c]s of 40,000 A/cm[sup 2] at 77 K (self field) and 9,000 A/cm[sup 2] at 77 K (1 T) have been achieved. The improved J. H characteristics may be attributed to microstructures consisting of uniform grain alignment throughout the entire cross section, intimate connection between grains, impurities within the grains, and an optimal level of dispersed 2212 phase. Irreversibility line measurements using both AC susceptibility in DC fields (reported elsewhere), and magnetization measurements, have indicated that flux pinning can be enhanced in the melt-processed samples over the results of normal solid-state processing with its less-than optimal 2212-phase content. But sufficiently long annealing times during the normal'' route may achieve 2212-phase content and J[sub c]s which are comparable to those of melt-processed samples.

Nanophase (n-) ZrO[sub 2] was produce in its pure and partially stabilized form by the gas-phase condensation method. The material was examined by x-ray diffraction and Raman scattering to obtain information on the structural evolution of the material during sintering. Two types of Y[sub 2]O[sub 3] doped ZrO[sub 2] doped ZrO[sub 2] nanophase materials were made, one by co-deposition of n-Y[sub 2]O[sub 3] and n-ZrO[sub 2]. We have determined that the co-deposition process is the most effect means of doping the n-ZrO[sub 2].

New measurements of the electric G[sub E](Q[sup 2]) and magnetic G[sub M](Q[sup 2]) form factors of the nucleons are reported. The proton data cover the Q[sup 2] range from 1.75 to 8.83 (GeV/c)[sup 2] and the neutron data from 1.75 to 4.00 (GeV/c)[sup 2], more than doubling the range of previous data. Scaled by the dipole fit, G[sub D](Q[sup 2]), the results for G[sub Mp](Q[sup 2])/[mu][sub p]G[sub D](Q[sup 2]) decrease smoothly from 1.05 to 0.92, while G[sub Ep](Q[sup 2])/G[sub D](Q[sup 2]) is consistent with unity. The preliminary results for Gm.(Q2)1 GD(Q2) consistent with unity, while F[sub En][sup 2] is consistent with zero at all values of Q[sup 2]. Comparisons are made to QCD Sum Rule, diquark, constituent quark, and VMD models, none of which agree with all of the new data.

Nanometer-scale atom clusters (with average diameters below 20 nm) of a variety of materials, including both metals and ceramics, have been synthesized by precursor evaporation and condensation in high-purity gases. The gas-entrained clusters can be collected and subsequently consolidated in situ under ultrahigh vacuum or other controlled atmosphere conditions to create bulk nanophase materials. These ultrafine-grained materials have properties that are often significantly different and considerably improved relative to those of their coarser-grained counterparts. The observed property changes relate to both their small grain sizes and the large percentage of their atoms in grain boundary environments. Since it is becoming apparent that their properties can be engineered during gas-phase synthesis and subsequent processing, nanophase materials assembled from atom clusters should have significant potential for technological development in a variety of applications. Some of the recent research on nanophase materials is reviewed.