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Resolution Improvement and Pattern Generator Development for theMaskless Micro-Ion-Beam Reduction Lithography System

Description: The shrinking of IC devices has followed the Moore's Law for over three decades, which states that the density of transistors on integrated circuits will double about every two years. This great achievement is obtained via continuous advance in lithography technology. With the adoption of complicated resolution enhancement technologies, such as the phase shifting mask (PSM), the optical proximity correction (OPC), optical lithography with wavelength of 193 nm has enabled 45 nm printing by immer… more
Date: May 18, 2006
Creator: Jiang, Ximan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Transition Armature Study. Progress report No. 4, February 1--March 31, 1992

Description: This forth report covers the period February 1 to March 31, 1992. During this period we: (1) performed numerical simulations of plasma brush formation and evolution with a 1D MHD code, (2) commenced testing hybrid armature brushes with a test fixture for studying hybrid armature brush behavior, (3) acquired 7m of the LTS railgun containment structure for a 3 year loan, (4) began evaluation of 3D Electro-Magnetic codes and their suitability to be interfaced to existing 3D stress/strain and therm… more
Date: May 18, 1992
Creator: Hawke, R. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Technology development for recirculating heavy-ion accelerators

Description: The {open_quotes}recirculator,{close_quotes} a recirculating heavy-ion accelerator has been identified as a promising approach for an inertial fusion driver. System studies have been conducted to evaluate the recirculator on the basis of feasibility and cost. The recirculator has been shown to have significant cost advantages over other potential driver schemes, but some of the performance requirements exceed the capabilities of present technology. The system studies identified the high leverag… more
Date: May 18, 1993
Creator: Newton, M. A. & Kirbie, H. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of the Super-B factory Design

Description: The SuperB international team continues to optimize the design of an electron-positron collider, which will allow the enhanced study of the origins of flavor physics. The project combines the best features of a linear collider (high single-collision luminosity) and a storage-ring collider (high repetition rate), bringing together all accelerator physics aspects to make a very high luminosity of 10{sup 36} cm{sup -2} sec{sup -1}. This asymmetric-energy collider with a polarized electron beam wil… more
Date: May 18, 2012
Creator: Wittmer, W.; U., /Michigan State; Bertsche, K.; Chao, A.; Novokhatski, A.; Nosochkov, Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Charm and Charmonium Spectroscopy at B-factories

Description: Since a few years, charm and charmonium spectroscopy has revived, both from experimental and theoretical point of views. Many new states have been discovered triggering numerous theoretical publications. The B-factories with their large enriched charm sample have played a leading role on the experimental side with the observation and study of most of the new states. Other experiments such as CLEO and CDF have also contributed. Classical hadron spectroscopy predicted some of these new states, bu… more
Date: May 18, 2007
Creator: Grenier, Philippe & /SLAC /Ecole Normale Superieure, CNRS
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SuperB: A High-Luminosity Asymmetric e+e- Super Flavor Factory

Description: We discuss herein the exciting physics program that can be accomplished with a very large sample of heavy quark and heavy lepton decays produced in the very clean environment of an e{sup +}e{sup -} collider; a program complementary to that of an experiment such as LHCb at a hadronic machine. It then presents the conceptual design of a new type of e{sup +}e{sup -} collider that produces a nearly two-order-of-magnitude increase in luminosity over the current generation of asymmetric B Factories. … more
Date: May 18, 2007
Creator: Bona, M. & al., /et
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Luminosity Variations Along Bunch Trains in PEP-II

Description: In the spring of 2005 after a long shut-down, the luminosity of the B-Factory PEP-II decreased along the bunch trains by about 25-30%. There were many reasons studied which could have caused this performance degradation, like a bigger phase transient due to an additional RF station in the Low-Energy-Ring (LER), bad initial vacuum, electron cloud, chromaticity, steering, dispersion in cavities, beam optics, etc. The initial specific luminosity of 4.2 sloped down to 3.2 and even 2.8 for a long tr… more
Date: May 18, 2007
Creator: Decker, F. J.; Boyes, M.; Colocho, W. S.; Novokhatski, A.; Sullivan, M. K.; Turner, J. L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beta-Beat Correction Using Strong Sextupole Bumps in PEP-II

Description: A method for correcting lattice beta mismatches has been developed for the PEP-II collider using orbit offsets in strong sextupoles. The solution is first predicted in the MAD program by modeling closed orbit bumps in the plane of correction at the sextupoles strongest in that plane. The derived solution is then tested in the machine to confirm prediction, and finally dialed into the machine under high-current conditions.
Date: May 18, 2007
Creator: Yocky, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tracking Down a Fast Instability in the PEP-II LER

Description: During Run 5, the beam in the PEP-II Low Energy Ring (LER) became affected by a predominantly vertical instability with very fast growth rate of 10...60/ms and varying threshold. The coherent amplitude of the oscillation was limited to approx. 1 mm peak and would damp down over a few tens of turns, however, beam loss set in even as the amplitude signal damped, causing a beam abort. This led to the conclusion that the bunches were actually blowing up. The appearance of a 2{nu}{sub S} line in the… more
Date: May 18, 2007
Creator: Wienands, U.; Akre, R.; Curry, S.; DeBarger, S.; Decker, F. J.; Ecklund, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Absolute Measurement of Electron Cloud Density in a Positively-Charged Particle Beam

Description: Clouds of stray electrons are ubiquitous in particle accelerators and frequently limit the performance of storage rings. Earlier measurements of electron energy distribution and flux to the walls provided only a relative electron cloud density. We have measured electron accumulation using ions expelled by the beam. The ion energy distribution maps the depressed beam potential and gives the dynamic cloud density. Clearing electrode current reveals the static background cloud density, allowing th… more
Date: May 18, 2006
Creator: Covo, M K; Molvik, A W; Friedman, A; Vay, J; Seidl, P A; Logan, B G et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Feedback Techniques and Ecloud Instabilites - Design Estimates

Description: The SPS at high intensities exhibits transverse single-bunch instabilities with signatures consistent with an Ecloud driven instability. While the SPS has a coupled-bunch transverse feedback system, control of Ecloud-driven motion requires a much wider control bandwidth capable of sensing and controlling motion within each bunched beam. This paper draws beam dynamics data from the measurements and simulations of this SPS instability, and estimates system requirements for a feedback system with … more
Date: May 18, 2009
Creator: Fox, J. D.; Mastorides, T.; Ndabashimiye, G.; Rivetta, C.; Winkle, D. Van; Byrd, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Pulser for the Tevatron electron lens gun

Description: To compensate for beam-beam interaction in Tevatron, an ''electron lens'' is considered to be an effective instrument. When a bunch of electrons with energy in the range (10-16) kV is overlapping with a bunch of antiprotons, the resulting focusing force for antiprotons can be adjusted by changing the electron beam current and by profiling its radial distribution. There exist several scenarios of how the system must function. According to one of them, an electron gun that supplies electrons must… more
Date: May 18, 2004
Creator: al., Iouri Terechkine et
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electroweak physics: search for zz and zw production in p anti-p collisions at s**(1/2) = 1.96 tev

Description: We present a search for ZZ and ZW vector boson pair production in p{bar p} collisions at {radical}s = 1.96 TeV using the leptonic decay channels ZZ {yields} llvv, ZZ {yields} lll'l' and ZW {yields} lll'v. In a data sample corresponding to an integrated luminosity of 194 pb{sup -1} collected with the Collider Detector at Fermilab, 3 candidate events are found with an expected background of 1.0 {+-} 0.2 events. We set a 95% confidence level upper limit of 15.2 pb on the cross section for ZZ plus … more
Date: May 18, 2005
Creator: Acosta, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MARS simulations of the NuMI primary beamline

Description: MARS is a Monte Carlo code for simulation of three-dimensional hadronic and electromagnetic cascades, muon and low-energy neutron transport in shielding and in accelerator and detector components in the energy range from a fraction of an eV up to 100 TeV. This report uses MARS to both transport the 120 GeV primary proton beam from the NuMI extraction Lambertsons through the NuMI Pre-target Hall and calculate the radiological effect of beam losses at various locations and for a variety of condit… more
Date: May 18, 2004
Creator: Striganov, Sergei I
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fiber positioning and MRS response

Description: This paper provides experimental results on the dependence of the output signal from small-area silicon photodetectors, such as MRS (Metal-Resistive layer-Semiconductor) photodiodes, on the fiber alignment.
Date: May 18, 2004
Creator: al., Pavel Polozov et
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Beam-Beam Simulations for a Single Pass SuperB-Factory

Description: A study of beam-beam collisions for an asymmetric single pass SuperB-Factory is presented [1]. In this scheme an e{sup -} and an e{sup +} beam are first stored and damped in two Damping Rings (DR), then extracted, compressed and focused to the IP. After collision the two beams are re-injected in the DR to be damped and extracted for collision again. The explored beam parameters are similar to those used in the design of the International Linear Collider, except for the beam energies. Flat beams… more
Date: May 18, 2007
Creator: Biagini, M. E.; Raimondi, P.; Seeman, J. & Schulte, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beam cooling: Principles and achievements

Description: After a discussion of Liouville's theorem, and its implications for beam cooling, a brief description is given of each of the various methods of beam cooling: stochastic, electron, radiation, laser, ionization, etc. For each, we present the type of particle for which it is appropriate, its range of applicability, and the currently achieved degree of cooling. For each method we also discuss the present applications and, also, possible future developments and further applications.
Date: May 18, 2003
Creator: Mohl, Dieter & Sessler, Andrew M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A new Mtest beamline for the 1999 fixed target run

Description: The beamline cryogenic system for the Meson area will not be run for the 1999 fixed target run. The current MTest (MT) beamline relies on cryogenic magnets. A non-cryogenic solution is proposed which can yield up to 1 x 10{sup 6} pions per cycle at 120 GeV/c per 1 x 10{sup 11} incident protons at 800 GeV/c.
Date: May 18, 2000
Creator: Kobilarcik, C. N. Brown and T. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron beam characterization at the Intense Pulsed Neutron Source.

Description: The Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory is a spallation neutron source dedicated to materials research. Its three cryogenic methane moderators provide twelve neutron beams to fourteen neutron scattering instruments and test facilities. The moderators at IPNS are of cryogenic methane (CH{sub 4}); one of liquid methane at 100 K, and two of solid methane at 30 K. These moderators produce intense beams of both cold and thermal neutrons. The moderators are each of a d… more
Date: May 18, 1998
Creator: Iverson, E. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Sampled Master Oscillator for the PEP-II B Factory

Description: A sampled phase-locked loop synchronizes the PEP-II B Factory rings to their SLAC Linac injector. The injection of both electrons and positrons into the separate rings and into their proper rf buckets requires phase shifting the linac rf with respect to the PEP rings. One of every three machine cycles provides the PEP ring an undisturbed reference while the other two thirds of the time the reference is unusable due to the injection scheme. The ring rf must be tunable about its nominal frequency… more
Date: May 18, 1999
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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