Search Results

open access

MPS II drift-chamber system

Description: A new system of detectors (MPS II) which has been installed and operated in the Brookhaven National Laboratory Multiparticle Spectrometer (MPS), consisting of short drift distance drift chambers is briefly described. (WHK)
Date: May 13, 1982
Creator: Etkin, A.; Eiseman, S. & Foley, K.J.
Partner: UNT Libraries Government Documents Department
open access

Initial measurements of beam breakup instability in the advanced test accelerator

Description: This paper reports the measurements of beam breakup (BBU) instability performed on the Advanced Test Accelerator (ATA) up to the end of February, 1984. The main objective was to produce a high current usable electron beam at the ATA output. A well-known instability is BBU which arises from the accelerator cavity modes interacting with the electron beam. The dominant mode is TM/sub 130/ at a frequency of approximately 785 MHz. It couples most strongly to the beam motion and has been observed to … more
Date: May 13, 1985
Creator: Chong, Y.P.; Caporaso, G.J. & Struve, K.W.
Partner: UNT Libraries Government Documents Department
open access

Two gauge boson physics at future colliders

Description: Electroweak unification suggests that there should be WW and ZZ physics analogous to {gamma}{gamma} physics. Indeed, WW and ZZ collisions will provide an opportunity to search for the Higgs boson at future high energy colliders. Cross sections in the picobarn range are predicted for Higgs boson production at the proposed 40-TeV SSC. While other states may be produced by WW and ZZ collisions, it is the Higgs boson that looms as the most attractive objective. 31 refs., 5 figs.
Date: May 13, 1988
Creator: Cahn, Robert N.
Partner: UNT Libraries Government Documents Department
open access

Molten salt processing of mixed wastes with offgas condensation

Description: We are developing an advanced process for treatment of mixed wastes in molten salt media at temperatures of 700--1000{degrees}C. Waste destruction has been demonstrated in a single stage oxidation process, with destruction efficiencies above 99.9999% for many waste categories. The molten salt provides a heat transfer medium, prevents thermal surges, and functions as an in situ scrubber to transform the acid-gas forming components of the waste into neutral salts and immobilizes potentially fugit… more
Date: May 13, 1991
Creator: Cooper, J.F.; Brummond, W.; Celeste, J.; Farmer, J.; Hoenig, C.; Krikorian, O.H. et al.
Partner: UNT Libraries Government Documents Department
open access

SYNCHROTRON RADIATION AND RING FORMATION IN THE ELECTRON RING ACCELERATOR

Description: We discuss the possibility of using synchrotron radiation to form electron rings having a very high electric field to hold the ions inside the ring. The formulas describing bow the energy and the dimension of the ring change under the effect of synchrotron radiation are derived, and a numerical example is given.
Date: May 13, 1970
Creator: Pellegrini, C.
Partner: UNT Libraries Government Documents Department
open access

Identification of the Origin of Monojet Signatures at the LHC

Description: Several new physics scenarios can lead to monojet signatures at the LHC. If such events are observed above the Standard Model background it will be important to identify their origin. In this paper we compare and contrast these signatures as produced in two very different pictures: vector or scalar unparticle production in the scale-invariant/conformal regime and graviton emission in the Arkani-Hamed, Dimopoulos and Dvali extra-dimensional model. We demonstrate that these two scenarios can be d… more
Date: May 13, 2008
Creator: Rizzo, Thomas G.
Partner: UNT Libraries Government Documents Department
open access

VARIATIONS IN REPRODUCTIVE TOXICANT IDENTIFICATION

Description: Reproductive toxicants are a very important class of compounds. They present unique hazards to those of child bearing ages, perform their 'dirty work' using a wide variety of mechanisms on a number of different organs, and are regulatorily important. Because of all of this, properly identifying reproductive toxicants is important, but fraught with difficulty. In this paper we will describe types or reproductive toxicants, their importance, and both mistakes and good practices that people who ar… more
Date: May 13, 2008
Creator: Simmons, F
Partner: UNT Libraries Government Documents Department
open access

Multiplicities in high energy interactions

Description: This paper reviews the data on multiplicities in high energy interactions. Results from e/sup +/e/sup -/ annihilation, from neutrino interactions, and from hadronic collisions, both diffractive and nondiffractive, are compared and contrasted. The energy dependence of the mean charged multiplicity, <n/sub ch/>, as well as the rapidity density at Y = 0 are presented. For hadronic collisions, the data on neutral pion production shows a strong correlation with <n/sub ch/>. The heavy particle fracti… more
Date: May 13, 1985
Creator: Derrick, M.
Partner: UNT Libraries Government Documents Department
open access

Collective accelerator for electron colliders

Description: A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch.
Date: May 13, 1985
Creator: Briggs, R. J.
Partner: UNT Libraries Government Documents Department
open access

Use of the ''MURA'' transformation to generate the fields and calculate the motion of protons in the designed Argonne Mini-ASPUN FFAG Spiral Sector Accelerator

Description: As a long range goal for the production of high intensity neutrons, Argonne National Laboratory has proposed the construction of a 1.5 GeV FFAG Spiral Sector Accelerator called ASPUN. The 500-MeV injector for this proposed accelerator is a smaller FFAG Spiral Sector Accelerator named Mini-ASPUN. Until such a time as the larger machine could be built, it was planned that Mini-ASPUN would replace the present RCS now being used for the IPNS program at Argonne. In order to obtain an accurate estima… more
Date: May 13, 1985
Creator: Crosbie, E.A.
Partner: UNT Libraries Government Documents Department
open access

The NO to NO{sub 2} conversion by ethylene oxidation

Description: A well-stirred reactor experiment and chemical kinetic modeling effort were performed in order to study the effect of ethylene oxidation on the conversion of nitric oxide (NO) to nitrogen dioxide (NO{sub 2}). Parameters examined in this study were temperature (1003--1260K) and input hydrocarbon concentration (220--3270 ppmv wet). The stirred reactor residence time was maintained at {approximately}2 milliseconds. Kinetic calculations indicated the NO to NO{sub 2} conversion proceeded through the… more
Date: May 13, 1994
Creator: Marinov, N. M.; Steele, R. C.; Malte, P. C. & Hori, M.
Partner: UNT Libraries Government Documents Department
open access

Burst mode FEL with the ETA-III induction linac

Description: Pulses of 140 GHz microwaves have been produced at a 2 kHz rate using the ETA-III induction linac and IMP wiggler. The accelerator was run in bursts of up to 50 pulses at 6 MeV and greater than 2 kA peak current. A feedback timing control system was used to synchronize acceleration voltage pulses with the electron beam, resulting in sufficient reduction of the corkscrew and energy sweep for efficient FEL operation. Peak microwave power for short bursts was in the range 0.5--1.1 GW, which is com… more
Date: May 13, 1993
Creator: Lasnier, C. J.; Allen, S. L. & Felker, B.
Partner: UNT Libraries Government Documents Department
open access

Refining a triangulation of a planar straight-line graph to eliminate large angles

Description: Triangulations without large angles have a number of applications in numerical analysis and computer graphics. In particular, the convergence of a finite element calculation depends on the largest angle of the triangulation. Also, the running time of a finite element calculation is dependent on the triangulation size, so having a triangulation with few Steiner points is also important. Bern, Dobkin and Eppstein pose as an open problem the existence of an algorithm to triangulate a planar straig… more
Date: May 13, 1993
Creator: Mitchell, S. A.
Partner: UNT Libraries Government Documents Department
open access

Intracavity adaptive correction of a 10 kW, solid-state, heat-capacity laser

Description: The Solid-State, Heat-Capacity Laser (SSHCL), under development at Lawrence Livermore National Laboratory (LLNL) is a large aperture (100 cm{sup 2}), confocal, unstable resonator requiring near-diffraction-limited beam quality. There are two primary sources of the aberrations in the system: residual, static aberrations from the fabrication of the optical components and predictable, time-dependent, thermally-induced index gradients within the gain medium. A deformable mirror placed within the ca… more
Date: May 13, 2004
Creator: LaFortune, K N; Hurd, R L; Brase, J M & Yamamoto, R M
Partner: UNT Libraries Government Documents Department
open access

Anodic Behavior of Alloy 22 in Calcium Chloride and in Calcium Chloride Plus Calcium Nitrate Brines

Description: Alloy 22 (UNS N60622) is a nickel-based alloy, which is extensively used in aggressive industrial applications, especially due to its resistance to localized corrosion and stress corrosion cracking in high chloride environments. The purpose of this work was to characterize the anodic behavior of Alloy 22 in concentrated calcium chloride (CaCl{sub 2}) brines and to evaluate the inhibitive effect of nitrate, especially to localized corrosion. Standard electrochemical tests such as polarization re… more
Date: May 13, 2003
Creator: Evans, K. J.; Day, S. D.; Ilevbare, G. O.; Whalen, M. T.; King, K. J.; Hust, G. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Accelerator and Ion Beam Tradeoffs for Studies of Warm Dense Matter

Description: One approach for heating a target to ''Warm Dense Matter'' conditions (similar, for example, to the interiors of giant planets or certain stages in Inertial Confinement Fusion targets), is to use intense ion beams as the heating source (see refs.[6] and [7] and references therein for motivation and accelerator concepts). By consideration of ion beam phase space constraints, both at the injector, and at the final focus, and consideration of simple equations of state and relations for ion stoppin… more
Date: May 13, 2005
Creator: Barnard, J. J.; Briggs, R. J.; Callahan, D. A.; Davidson, R. C.; Friedman, A.; Grisham, L. et al.
Partner: UNT Libraries Government Documents Department
open access

Application of the Principle of Maximum Conformality to Top-Pair Production

Description: A major contribution to the uncertainty of finite-order perturbative QCD predictions is the perceived ambiguity in setting the renormalization scale {mu}{sub r}. For example, by using the conventional way of setting {mu}{sub r} {element_of} [m{sub t}/2, 2m{sub t}], one obtains the total t{bar t} production cross-section {sigma}{sub t{bar t}} with the uncertainty {Delta}{sigma}{sub t{bar t}}/{sigma}{sub t{bar t}} {approx} (+3%/-4%) at the Tevatron and LHC even for the present NNLO level. The Pri… more
Date: May 13, 2013
Creator: Brodsky, Stanley J.; Wu, Xing-Gang & Dept of Physics, Chongqing University, China
Partner: UNT Libraries Government Documents Department
open access

Rhodium-Catalyzed C-C Bond Formation via Heteroatom-Directed C-H Bond Activation

Description: Once considered the 'holy grail' of organometallic chemistry, synthetically useful reactions employing C-H bond activation have increasingly been developed and applied to natural product and drug synthesis over the past decade. The ubiquity and relative low cost of hydrocarbons makes C-H bond functionalization an attractive alternative to classical C-C bond forming reactions such as cross-coupling, which require organohalides and organometallic reagents. In addition to providing an atom economi… more
Date: May 13, 2010
Creator: Colby, Denise; Bergman, Robert & Ellman, Jonathan
Partner: UNT Libraries Government Documents Department
open access

EFFECT OF PRETREATMENT ON PT-CO/C CATHODE CATALYSTS FOR THE OXYGEN-REDUCTION REACTION

Description: In order to reduce the precious metal loading without sacrificing activity and stability, a new method for the preparation of bimetallic catalysts is proposed. Currently, Pt-alloy particles, with 2 to 3 nm in diameter, are loaded on high surface area carbon supports. Of the Pt loaded, only the surface atoms interact with the reactants. In order to increase the Pt utilization per metal particle the new process for catalyst preparation will incorporate a non-noble transition metal core coated wit… more
Date: May 13, 2009
Creator: Fox, E.
Partner: UNT Libraries Government Documents Department
open access

Calibrating Accelerometers Using an Electromagnetic Launcher

Description: A Pulse Forming Network (PFN), Helical Electromagnetic Launcher (HEML), Command Module (CM), and Calibration Table (CT) were built and evaluated for the combined ability to calibrate an accelerometer. The PFN has a maximum stored energy of 19.25 kJ bank and is fired by a silicon controlled rectifier (SCR), with appropriate safety precautions. The HEML is constructed out of G-10 fiberglass and is designed to accelerate 600 grams to 10 meters per second. The CM is microcontroller based running Ar… more
Date: May 13, 2012
Creator: Timpson, Erik
Partner: UNT Libraries Government Documents Department
Back to Top of Screen