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Results of Beam Inflection Tests

Description: "An experimental study has been made regarding the passage of a beam of 100-kV ions (H⁺ and H₂⁺) across a magnetic field by means of a crossed electric field." This experiment was designed to answer the following questions: "(1) Is there a limit to the current that will traverse a magnetic field by the action of a crossed electric field? If so, what is the limit? (2) Do difficulties arise in maintaining the electric field? (3) For the source employed, what is the angular divergence and current … more
Date: April 1, 1957
Creator: Linlor, William I., 1915-
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Panel session: Part 1, In flux -- Science Policy and the social structure of Big Laboratories, 1964--1979

Description: This report discusses the in flux of science policy and the social structure of big laboratories during the period of 1964 to 1979 and some sociological consequences of high energy physicists` development of the standard model during the same period.
Date: September 1, 1993
Creator: Westfall, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The generalized Erlangen program and setting a geometry for four- dimensional conformal fields

Description: This is the text of a talk at the International Symposium on ``Mathematical Physics towards the XXI Century`` held in March 1993 at Beersheva, Israel. In the first part we attempt to summarize XXth Century Physics, in the light of Kelvin`s 1900 speech ``Dark Clouds over XIXth Century Physics.`` Contrary to what is usually said, Kelvin predicted that the ``clouds`` (relativity and quantum mechanics) would revolutionize physics and that one hundred years might be needed to harmonize them with cla… more
Date: October 22, 1993
Creator: Ne`eman, Y.; Hehl, F. W. & Mielke, E. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The MuCool Test Area and RF Program

Description: The MuCool RF Program focuses on the study of normal conducting RF structures operating in high magnetic field for applications in muon ionization cooling for Neutrino Factories and Muon Colliders. This paper will give an overview of the program, which will include a description of the test facility and its capabilities, the current test program, and the status of a cavity that can be rotated in the magnetic field which allows for a more detailed study of the maximum stable operating gradient v… more
Date: May 1, 2010
Creator: Bross, A. D.; Jansson, A.; Moretti, A.; Yonehara, K.; Huang, D.; Torun, Y. et al.
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Partner: UNT Libraries Government Documents Department
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Band Collapse and the Quantum Hall Effect in Graphene

Description: The recent Quantum Hall experiments in graphene have confirmed the theoretically well-understood picture of the quantum Hall (QH) conductance in fermion systems with continuum Dirac spectrum. In this paper we take into account the lattice, and perform an exact diagonalization of the Landau problem on the hexagonal lattice. At very large magnetic fields the Dirac argument fails completely and the Hall conductance, given by the number of edge states present in the gaps of the spectrum, is dominat… more
Date: March 16, 2010
Creator: Bernevig, B.Andrei; Hughes, Taylor L.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.; Chen, Han-Dong; /Illinois U., Urbana et al.
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Partner: UNT Libraries Government Documents Department
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Long-term monitoring of ULF electromagnetic fields at Parkfield, CA

Description: Electric and magnetic fields in the (10{sup -4}-1.0) Hz band were monitored at two sites adjacent to the San Andreas Fault near Parkfield and Hollister, California from 1995 to present. A data window [2002-2005], enclosing the September 28, 2004 M6 Parkfield earthquake, was analyzed to determine if anomalous electric or magnetic fields, or changes in ground conductivity, occurred before the earthquake. The data were edited, removing intervals of instrument malfunction leaving 875 days in the fo… more
Date: August 1, 2009
Creator: Kappler, K. N.; Morrison, H. F. & Egbert, G. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fluctuations of the van der Waals attraction force between macroscopic bodies

Description: The tliccry of the fluctuations of the van der Waals (vdW) attractive force between macroscopic bodies is developed. A general equation for the spectral density of the fluctuating surface Maxwell stress (force per unit mea.) in va,cuurn nea,r the surface of a body is derived under the assumption that, inside the bodies, the random La.ngevin sources of the electric and magnetic fields (charges, polarizations, currents) are Gaussian. This spectral density of stress is an integral over frequencies… more
Date: January 1, 2003
Creator: Kogan, A. S. (Aleksandr Semenovich)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Geophysical Techniques for Monitoring CO2 Movement During Sequestration

Description: The relative merits of the seismic, gravity, and electromagnetic (EM) geophysical techniques are examined as monitoring tools for geologic sequestration of carbon dioxide (CO{sub 2}). This work does not represent an exhaustive study, but rather demonstrates the capabilities of a number of geophysical techniques for two synthetic modeling scenarios. The first scenario represents combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the Schrader Bluff field on… more
Date: November 15, 2005
Creator: Gasperikova, Erika & Hoversten, G. Michael
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A SQUID-based microwave cavity search for dark-matter axions

Description: Axions in the {mu}eV mass range are a plausible cold dark matter candidate and may be detected by their conversion into microwave photons in a resonant cavity immersed in a static magnetic field. The first result from such an axion search using a superconducting first-stage amplifier (SQUID) is reported. The SQUID amplifier, replacing a conventional GaAs field-effect transistor amplifier, successfully reached axion-photon coupling sensitivity in the band set by present axion models and sets the… more
Date: October 21, 2009
Creator: Asztalos, S. J.; Carosi, G.; Hagmann, C.; Kinion, D.; van Bibber, K.; Hotz, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experimental Verification of the Hall Effect during Magnetic Reconnection in a Laboratory Plasma

Description: In this letter we report a clear and unambiguous observation of the out-of-plane quadrupole magnetic field suggested by numerical simulations in the reconnecting current sheet in the Magnetic Reconnection Experiment (MRX). Measurements show that the Hall effect is large in collisionless regime and becomes small as the collisionality increases, indicating that the Hall effect plays an important role in collisionless reconnection.
Date: June 16, 2005
Creator: Ren, Yang; Yamada, Masaaki; Gerhardt, Stefan; Ji, Hantao; Kulsrud, Russell & Kuritsyn, Aleksey
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final report [The 15th Workshop on Electromagnetic Induction in the Earth, held 8/20-26/2000, and The 5th Magnetotelluric Data Interpretation Workshop, 8/17-19/2000]

Description: This document reports on how the DOE helped to support travel of students and scientists to the conferences in Brazil. Attendee names, funding, and session titles are listed.
Date: June 25, 2002
Creator: Alumbaugh, David L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Conceptual Design of Pion Capture Magnets of Up to 15 Cm Bore and 20 T Peak Field.

Description: For the Neutrino Factory and Muon Collider Collaboration, BNL has considered solenoidal magnet systems of several types to capture pions generated by bombarding a mercury jet with multi-GeV protons. The magnet systems generate up to 20 T, uniform to 5% throughout a cylindrical volume 0.15 m in diameter and 0.6 m long. Axially downstream the field ramps gradually downward by a factor of sixteen, while the bore increases fourfold. The steady-state system needed for an accelerator has many superco… more
Date: September 24, 2001
Creator: Weggel, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An Investigation of the Effects of a Driven Plasma Rotation on Fluctuation in a Magnetized Linear Plasma Source. Final Technical Report

Description: The rotation of a plasma is one of the most fundamental global modes of plasma behavior. It is the zeroth order plasma response to a transverse electric field. In its simplest kinetic form, the so-called E x B drift (here, E is the electric field vector and B is the magnetic field vector), both the ions and the electrons will undergo a drift in the same direction. This motion is considered a universal mode of a plasma since the mechanism of the E x B drift is, to zero-order, independent of both… more
Date: May 18, 2004
Creator: Thomas, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Greybull Sandstone Petroleum Potential on the Crow Indian Reservation, South-Central Montana

Description: The focus of this project was to explore for stratigraphic traps that may be present in valley-fill sandstone at the top of the Lower Cretaceous Kootenai Formation. This sandstone interval, generally known as the Greybull Sandstone, has been identified along the western edge of the reservation and is a known oil and gas reservoir in the surrounding region. The Greybull Sandstone was chosen as the focus of this research because it is an excellent, well-documented, productive reservoir in adjacen… more
Date: May 13, 2002
Creator: Lopez, David A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Assembly of LIGA using Electric Fields

Description: The goal of this project was to develop a device that uses electric fields to grasp and possibly levitate LIGA parts. This non-contact form of grasping would solve many of the problems associated with grasping parts that are only a few microns in dimensions. Scaling laws show that for parts this size, electrostatic and electromagnetic forces are dominant over gravitational forces. This is why micro-parts often stick to mechanical tweezers. If these forces can be controlled under feedback contro… more
Date: April 1, 2002
Creator: FEDDEMA, JOHN T.; WARNE, LARRY K.; JOHNSON, WILLIAM A.; OGDEN, ALLISON J. & ARMOUR, DAVID L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Scale-invariant Lipatov kernels from t-channel unitarity

Description: The Lipatov equation can be regarded as a reggeon Bethe-Salpeter equation in which higher-order reggeon interactions give higher-order kernels. Infra-red singular contributions in a general kernel are produced by t-channel nonsense states and the allowed kinematic forms are determined by unitarity. Ward identity and infra-red finiteness gauge invariance constraints then determine the corresponding scale-invariant part of a general higher-order kernel.
Date: November 14, 1994
Creator: Coriano, C. & White, A. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chatter suppression through variable impedance and smart fluids

Description: A novel approach to mitigating chatter vibrations in machine tools is presented. Encountered in many types of metal removal processes, chatter is a dangerous condition which results from the interaction of the cutting dynamics with the modal characteristics of the machine-workpiece assembly. Tool vibrations are recored on the surface of the workpiece during metal removal, imposing a waviness which alters the chip thickness during subsequent cutting passes. Deviations from the nominal chip thick… more
Date: February 1, 1996
Creator: Segalman, D. & Redmond, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phonons in Intrinsic Josephson Systems

Description: Subgap structures in the I-V curves of layered superconductors are explained by the excitation of phonons by Josephson oscillations. In the presence of a magnetic field applied parallel to the layers additional structures due to fluxon motion appear. Their coupling with phonons is investigated theoretically and a shift of the phonon resonances in strong magnetic fields is predicted.
Date: October 1, 2000
Creator: Preis, C. & Schmalzl, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dynamic Devices: Pickups and Pickers

Description: A large proportion of the dynamic devices used to interact with the charged-particle beams in accelerators or storage rings can be classified as pickups or kickers. These devices act through time-varying electromagnetic fields either to extract information about the particle's motion or to effect a change in that motion. A given configuration of electrodes may be used either as a pickup or as a kicker; that duality will be addressed in this paper. An example of a simple electrode is the loop an… more
Date: August 1, 1986
Creator: Lambertson, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electric power high-voltage transmission lines: Design options, cost, and electric and magnetic field levels

Description: This report provides background information about (1) the electric and magnetic fields (EMFs) of high-voltage transmission lines at typical voltages and line configurations and (2) typical transmission line costs to assist on alternatives in environmental documents. EMF strengths at 0 {+-} 200 ft from centerline were calculated for ac overhead lines, and for 345 and 230-kV ac underground line and for a {+-}450-kV dc overhead line. Compacting and height sensitivity factors were computed for the … more
Date: November 1, 1994
Creator: Stoffel, J. B.; Pentecost, E. D.; Roman, R. D. & Traczyk, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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