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Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.

This paper addresses the need to support a very precise optical instrument while causing essentially no influence to its natural shape. Such influences could come from a number of sources, such as manufacturing tolerances, temperature changes, over-constrained structural members, or ground motion. Kinematic couplings have long been used for purposes of repeatable location and minimal influence to the supported object, however these couplings typically offer very little damping. This paper presents a kinematic coupling that utilizes constrained-layer damping techniques to damp out the first three modes of vibration of a precision optical instrument. Finite element analysis was used to aid in the design and tuning of the dampers for the kinematic coupling. Experimental tests were conducted and confirmed the effectiveness of the dampers. The quality factor (Q), which measure the amplification at resonance, dropped from 33.3 to 5.9 on the first mode, from 156.3 to 7.1 on the second mode, and from 147.1 to 18.5 on the third mode. These dampers help to ensure that the stringent vibration requirements necessary to produce high quality optical images are met.

A generalized version of the Lindemann melting criterion has recently been used to develop a unified thermodynamic description of disorder-induced amorphization and heat-induced melting. This concept of amorphization as a melting process is based on the fact that the melting temperature of a defective crystal driven far from equilibrium will decrease relative to that of its defect-free equilibrium state. The broader view of melting provides a new perspective of damage-accumulation processes such as radiation damage, ion implantation, ion beam mixing, plastic deformation, and fracture. For example, within this conceptual framework, disorder-induced amorphization is simply polymorphous melting of a critically disordered crystal at temperatures below the glass transition temperature. In the present communication, we discuss the application of the concept to two specific cases: amorphous phase formation during ion implantation and solute segregation-induced intergranular fracture.

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A letter report issued by the General Accounting Office with an abstract that begins "This report focuses on school and community collaborations for improving student outcomes for at-risk youth. To better provide the support needed for these students to succeed in school and beyond, some schools and school districts have intensified their collaboration with businesses, community agencies, and other neighborhood organizations. These efforts, which go substantially beyond the usual links between schools and other agencies or organizations, go by such names as "extended-service schools," "full- service schools," "community schools," or, more generally, "school-community initiatives." The federal government plays a role in these initiatives because of the funding and support it provides through various programs serving youths who are disadvantaged or at risk of school failure. Schools with a large number of disadvantaged students often struggle to both educate their students and prepare them for further education or a career. The goals of the school-community initiatives GAO reviewed center on helping students achieve in school and readying them for life after graduation. Several officials GAO spoke with said that it is difficult to measure the success of these programs for at-risk youth. Officials cited the lack of funds and the complex …

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From 1992 to 1995 the CDF experiment has taken 110 pb{sup {minus}1} of p{anti p} collisions at a center-of-mass energy of 1.8 TeV. These data gave rise to a variety of important B physics measurements. Most importantly B mass, lifetime and mixing measurements, the observation of the last missing meson, the B{sub c}, and a measurement of the CP violation parameter sin 2{beta}. The highlights of those results are described and a perspective for the upcoming Run II period is given.

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.

Semiweekly newspaper from Brady, Texas that includes local, state, and national news along with advertising.

Real time pattern recognition is becoming a key issue in many position sensitive detector applications. The CDF collaboration is building SVT: a specialized electronic device designed to perform real time track reconstruction using the silicon vertex detector (SVX II). This will strongly improve the CDF capability of triggering on events containing b quarks, usually characterized by the presence of a secondary vertex. SVT is designed to reconstruct in real time charged particles trajectories using data coming from the Silicon Vertex detector and the Central Outer Tracker drift chamber. The SVT architecture and algorithm have been specially tuned to minimize processing time without degrading parameter resolution.

In this paper the authors present results on Charm and Beauty production as well as on production and polarization of Quarkonia at {radical}s = 1.8 TeV. These results were obtained from data taken with the CDF detector at Fermilab. They cover recently completed analyses of the 1992--96 collider run.

The total costs and impacts of expanding energy use in China will depend, in part, on a number of important factors, an understanding of which is vital for China's policy-makers. These issues include the additional environmental and public health impacts associated with energy use, the economic costs of infrastructure expansion to meet growing energy needs, and the potential role that renewable energy technologies could play if pushed hard in China's energy future. This short report summarizes major trends and issues in each of these three areas.

This report examines the major, foreign conventional weapon systems that China has acquired or has committed to acquire since 1990, with particular attention to implications for U.S. security concerns. It is not the assumption of this report that China’s military, the People’s Liberation Army (PLA), will engage in conflict with other forces in Asia. Nonetheless, since the mid-1990s, there has been increasing concern about China’s assertiveness in Asia and greater threats against Taiwan.

Diffractive, exclusive di-jet events produced by 500 GeV/c {pi}{sup {minus}} scattered off nuclei were used to measure their A-dependence, and to make the first direct measurement of the valence-quark momentum distribution in pions. Data on the latter are compared to two limiting predictions for the pion light-cone wave-function. The results show that the asymptotic wave-function of perturbative QCD describes the data well for Q{sup 2} of 10 GeV{sup 2} and above. The measured A-dependence is consistent with observation of point-like configurations in the pion and color-transparency calculations.

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Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Two of the greatest mysteries of modern physics are the origin of the dark matter in the universe and the nature of the highest energy particles in the cosmic ray spectrum. The authors discuss here possible direct and indirect connections between these two problems, with particular attention to two cases: in the first they study the local clustering of possible sources of ultra-high energy cosmic rays (UHECRs) driven by the local dark matter overdensity. In the second case they study the possibility that UHECRs are directly generated by the decay of weakly unstable super heavy dark matter.

The 106th Congress is considering a general overhaul of derivatives regulation. Pending legislation would codify the unregulated status of certain derivatives, exempt many other currently-regulated contracts from oversight by the Commodity Futures Trading Commission, and permit the trading of a new kind of contract: a futures contract based on the stock of an individual corporation. Derivatives legislation has been reported out of committee in both House and Senate. This report analyzes this legislation in the 106th Congress, and will be updated as developments warrant.

The {gamma} Doradus stars are a newly-discovered class of gravity-mode pulsators which lie just at or beyond the red edge of the {delta} Scuti instability strip. We present the results of calculations which predict pulsation instability of high-order g-modes with periods between 0.4 and 3 days, as observed in these stars. The pulsations are driven by the modulation of radiative flux by convection at the base of a deep envelope convection zone. Pulsation instability is predicted only for models with temperatures at the convection zone base between {approximately}200,000 and {approximately}480,000 K. The estimated shear dissipation due to turbulent viscosity within the convection zone, or in an overshoot region below the convection zone, can be comparable to or even exceed the predicted driving, and is likely to reduce the number of unstable modes, or possibly to quench the instability. Additional refinements in the pulsation modeling are required to determine the outcome. A few Doradus stars have been observed that also pulsate in {delta} Scuti-type p-modes, and at least two others have been identified as chemically peculiar. Since our calculated driving region is relatively deep, Doradus pulsations are not necessarily incompatible with surface abundance peculiarities or with {delta} Scuti p-mode pulsations driven …

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The A0 photo-injector produces electron bunches of 1--14 nC charge with an energy of 18 MeV. Detailed measurements and optimization of emittance have been carried out for a number of gun and laser operating conditions, beam line optics conditions, and at a number of beam line locations. Results are compared with the predictions of simulations using HOMDYN.

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