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open access

$D^0 \bar{D}^0$ Mixing at BaBar

Description: This article reviews the recent measurement of D{sup 0}-{bar D}{sup 0} mixing with the D{sup 0} {yields} K{pi} decay channel from the BABAR experiment at the PEP-II B-Factory. Averages from the Heavy Flavor Averaging Group between this result and a previous result from BELLE are also presented.
Date: October 26, 2011
Creator: Coleman, Jonathon
open access

A 3-D hydrodynamic dispersion model for modeling tracer transport in Geothermal Reservoirs

Description: A 3-D hydrodynamic dispersion model for tracer transport is developed and implemented into the TOUGH2 EOS3 (T2R3D) module. The model formulation incorporates a full dispersion tensor, based on a 3-D velocity field with a 3-D, irregular grid in a heterogeneous geological system. Two different weighting schemes are proposed for spatial average of 3-D velocity fields and concentration gradients to evaluate the mass flux by dispersion and diffusion of a tracer or a radionuclide. This new module of … more
Date: January 26, 1998
Creator: Wu, Yu-Shu & Pruess, Karsten
open access

11.424 Ghz Stripline Transversal Filter for Sub-Picosecond Bunch Timing Measurements

Description: Measurement of time-of-arrival or instantaneous longitudinal position is a fundamental beam diagnostic. We present results from a stripline transversal periodic coupler structure which forms the heart of a sub-ps beam timing detector. This filter structure approximates a sinx/x response in the frequency domain which corresponds to a limited pulse length response in the time domain. These techniques have been used extensively in beam feedback systems at 3 GHz center frequencies with operational … more
Date: August 26, 2010
Creator: Van Winkle, D.; Young, A. & Fox, J. D.
open access

A 15-T Pulsed Solenoid for a High-Power Target Experiment

Description: The MERIT experiment, to be run at CERN in 2007, is a proof-of-principle test for a target system that converts a 4-MW proton beam into a high-intensity muon beam for either a neutrino factory complex or a muon collider. The target system is based on a free mercury jet that intercepts an intense proton beam inside a 15-T solenoidal magnetic field. Here, we describe the design and initial performance of the 15-T, liquid-nitrogen-precooled, copper solenoid magnet.
Date: June 26, 2006
Creator: Kirk, H. G.; Efthymiopoulos, I.; Fabich, A.; Haug, R.; Titus, P.; McDonald, K. T. et al.
open access

1963 revisited: should we set a precedent of recalculating old exposures

Description: This paper describes recent experience in re-evaluating the dose to an employee. This employee was plagued with skin disorders for years, but he questioned his recorded beta dose only after a recent LLNL cancer study began collecting data. He was concerned that his radiation dose recorded during the time he worked on a fission burst reactor experiment in 1963 did not represent the actual dose he received. About six months were spent gathering information, putting the information together, makin… more
Date: October 26, 1981
Creator: Hoots, S.S.
open access

1st-Principles Step- and Kink-Formation Energies on Cu(111)

Description: In rough agreement with experimental values derived from Cu island shapes vs. temperature, ab-initio calculations yield formation energies of 0.27 and 0.26 eV/ step-edge-atom for (100)- and (111)-micro facet steps on Cu(lll), and 0.09 and 0.12 eV per kink in those steps. Comparison to ab-initio results for Al and Pt shows that as a rule, the average formation energy of straight steps on a close-packed metal surface equals -7% of the metal's cohesive energy.
Date: May 26, 1999
Creator: Feibelman, Peter J.
open access

The 2005 National Conference of Black Physics Students

Description: This proposal funded the 19th Annual National Conference of Black Physics Students. This conference provided physics students with the opportunity to interact with world-class researchers and the facilities at which they work. The conference supports the well established need for the US to foster a larger and stronger scientific workforce through the recruitment and retention of science and engineering students.
Date: September 26, 2006
Creator: Reid, David D.
open access

21nm X-Ray Laser Thomson Scattering of Laser-Heated Exploding Foil Plasmas

Description: Recent experiments were carried out on the Prague Asterix Laser System (PALS) towards the demonstration of a soft x-ray laser Thomson scattering diagnostic for a laser-produced exploding foil. The Thomson probe utilized the Ne-like zinc x-ray laser which was double-passed to deliver {approx}1 mJ of focused energy at 21.2 nm wavelength and lasting {approx}100 ps. The plasma under study was heated single-sided using a Gaussian 300-ps pulse of 438-nm light (3{omega} of the PALS iodine laser) at la… more
Date: September 26, 2007
Creator: Dunn, J.; Rus, B.; Mocek, T.; Nelson, A. J.; Foord, M. E.; Rozmus, W. et al.
open access

27Al and 1H Solid State NMR Studies Show Evidence of TiAl3 and TiH2 in Ti-doped NaAlH4

Description: Previous X-ray Diffraction (XRD) and Nuclear Magnetic Resonance (NMR) studies on Ti-doped NaAlH{sub 4} revealed the reaction products of two heavily doped (33.3 at.%) samples that were solvent-mixed and mechanically-milled. This investigation revealed that nano-crystalline or amorphous Al{sub 2}O{sub 3} forms from the possible coordination of aluminum with oxygen atom of the furan ring system from added tetrahydrofuran (THF) in the solvent-mixed sample, and that TiAl{sub 3} forms in mechanicall… more
Date: May 26, 2005
Creator: Herberg, J; Maxwell, R & Majzoub, E
open access

800MHz Crab Cavity Conceptual Design For the LHC Upgrade

Description: In this paper, we present an 800 MHz crab cavity conceptual design for the LHC upgrade. The cell shape is optimized for lower maximum peak surface fields as well as higher transverse R/Q. A compact coax-to-coax coupler scheme is proposed to damp the LOM/SOM modes. A two-stub antenna with a notch filter is used as the HOM coupler to damp the HOM modes in the horizontal plane and rejects the operating mode at 800MHz. Multipacting (MP) simulations show that there are strong MP particles at the dis… more
Date: May 26, 2009
Creator: Xiao, Liling; Li, Zenghai; Ng, Cho-Kuen; Seryi, Andrei & /SLAC
open access

Ab Initio Many-Body Calculations Of n-3H, n-4He, p-3,4He, And n-10Be Scattering

Description: We develop a new ab initio many-body approach capable of describing simultaneously both bound and scattering states in light nuclei, by combining the resonating-group method with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters. This approach preserves translational symmetry and Pauli principle. We present phase shifts for neutron scattering on {sup 3}H, {sup 4}He and {sup 10}Be and proton scattering on {sup 3,4}He, using realistic nucleon-… more
Date: March 26, 2008
Creator: Quaglioni, S & Navratil, P
open access

Ab initio study of low-energy electron collisions withtertafluoroethene, C2F4

Description: We report the results of variational calculations of elastic electron scattering by tetrafluoroethene, C{sub 2}F{sub 4}, with incident electron energies ranging from 0.5 to 20 eV, using the complex Kohn method and effective core potentials. These are the first fully calculations to reproduce experimental angular differential cross sections at energies below 10 eV. Low-energy electron scattering by C{sub 2}F{sub 4} is sensitive to the inclusion of electronic correlation and target-distortion eff… more
Date: April 26, 2004
Creator: Trevisan, C. S.; Orel, A. E. & Rescigno, Thomas N.
open access

Abrupt onset of a second energy gap at the superconducting transition of underdoped Bi2212

Description: he superconducting gap--an energy scale tied to the superconducting phenomena--opens on the Fermi surface at the superconducting transition temperature (Tc) in conventional BCS superconductors. In underdoped high-Tc superconducting copper oxides, a pseudogap (whose relation to the superconducting gap remains a mystery) develops well above Tc (refs 1, 2). Whether the pseudogap is a distinct phenomenon or the incoherent continuation of the superconducting gap above Tc is one of the central questi… more
Date: May 26, 2007
Creator: Hussain, Zahid; Lee, W. S.; Vishik, I. M.; Tanaka, K.; Lu, D. H.; Sasagawa, T. et al.
open access

Absorptance Measurements of Optical Coatings - A Round Robin

Description: An international round robin study was conducted on the absorption measurement of laser-quality coatings. Sets of optically coated samples were made by a ''reactive DC magnetron'' sputtering and an ion beam sputtering deposition process. The sample set included a high reflector at 514 nm and a high reflector for the near infrared (1030 to 1318 nm), single layers of silicon dioxide, tantalum pentoxide, and hafnium dioxide. For calibration purposes, a sample metalized with hafnium and an uncoated… more
Date: October 26, 2000
Creator: Chow, R; Taylor, J R; Wu, Z L; Boccara, C A; Broulik, U; Commandre, M et al.
open access

Acceleration of compact toroid plasma rings for fusion applications

Description: We describe experimental results for a new type of collective accelerator based on magnetically confined compact torus (CT) plasma rings and discuss applications to both inertial and magnetic fusion. We have demonstrated the principle of CT acceleration in the RACE device with acceleration of 0.5 mg ring masses to 400 km/s and 0.02 mg ring masses to 1400 km/s at greater than or equal to30% efficiency. Scaling the CT accelerator to the multi-megajoule level could provide an efficient, economical… more
Date: August 26, 1988
Creator: Hartman, C. W.; Barr, W. L.; Eddleman, J. L.; Gee, M.; Hammer, J. H.; Ho, S. K. et al.
open access

Acceleration of Polarized Protons in the AGS With Two Helical Partial Snakes.

Description: Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult: the depolarizing resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions and are not feasible in the AGS since straight sections are too short. Recently, two helical partial snakes with double pitch design have been built and installed in the AGS. With careful setup of optics at injection and along the ramp, this combination c… more
Date: June 26, 2006
Creator: Huang, H.; Ahrens, L. A.; Bai, M.; Bravar, A.; Brown, K.; Courant, E. D. et al.
open access

ACCELERATION PHYSICS CODE WEB REPOSITORY.

Description: In the framework of the CARE HHH European Network, we have developed a web-based dynamic accelerator-physics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.
Date: June 26, 2006
Creator: WEI, J.
open access

Accelerator-based atomic physics experiments with photon and ion beams

Description: Accelerator-based atomic physics experiments at Brookhaven presently use heavy-ion beams from the Dual MP Tandem Van de Graaff Accelerator Facility for atomic physics experiments of several types. Work is presently in progress to develop experiments which will use the intense photon beams which will be available in the near future from the ultraviolet (uv) and x-ray rings of the National Synchrotron Light Source (NSLS). Plans are described for experiments at the NSLS and an exciting development… more
Date: April 26, 1984
Creator: Johnson, B. M.; Jones, K. W. & Meron, M.
open access

Accepting Mixed Waste as Alternate Feed Material for Processing and Disposal at a Licensed Uranium Mill

Description: Certain categories of mixed wastes that contain recoverable amounts of natural uranium can be processed for the recovery of valuable uranium, alone or together with other metals, at licensed uranium mills, and the resulting tailings permanently disposed of as 11e.(2) byproduct material in the mill's tailings impoundment, as an alternative to treatment and/or direct disposal at a mixed waste disposal facility. This paper discusses the regulatory background applicable to hazardous wastes, mixed w… more
Date: February 26, 2002
Creator: Frydenland, D. C.; Hochstein, R. F. & Thompson, A. J.
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