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2 MW upgrade of the Fermilab Main Injector (open access)

2 MW upgrade of the Fermilab Main Injector

In January 2002, the Fermilab Director initiated a design study for a high average power, modest energy proton facility. An intensity upgrade to Fermilab's 120-GeV Main Injector (MI) represents an attractive concept for such a facility, which would leverage existing beam lines and experimental areas and would greatly enhance physics opportunities at Fermilab and in the U.S. With a Proton Driver replacing the present Booster, the beam intensity of the MI is expected to be increased by a factor of five. Accompanied by a shorter cycle, the beam power would reach 2 MW. This would make the MI a more powerful machine than the SNS or the J-PARC. Moreover, the high beam energy (120 GeV) and tunable energy range (8-120 GeV) would make it a unique high power proton facility. The upgrade study has been completed and published. This paper gives a summary report.
Date: June 4, 2003
Creator: Chou, Weiren
System: The UNT Digital Library
An 8-GeV Synchrotron-Based Proton Driver (open access)

An 8-GeV Synchrotron-Based Proton Driver

In January 2002, the Fermilab Director initiated a design study for a high average power, modest energy proton facility. Such a facility is a possible candidate for a construction project in the U.S. starting in the middle of this decade. The key technical element is a new machine, dubbed the ''Proton Driver,'' as a replacement of the present Booster. The study of an 8-GeV synchrotron-based proton driver has been completed and published. This paper will give a summary report, including machine layout and performance, optics, beam dynamics issues, technical systems design, civil construction, cost estimate and schedule.
Date: June 4, 2003
Creator: Chou, Weiren
System: The UNT Digital Library
Absorption and emission spectra of Ce{sup 3+} in elpasolite lattices (open access)

Absorption and emission spectra of Ce{sup 3+} in elpasolite lattices

None
Date: June 12, 2003
Creator: Tanner, Peter A.; Mak, Chris S.K.; Edelstein, Norman M.; Murdoch, Keith M.; Liu, Guokiu; Huang, Jin et al.
System: The UNT Digital Library
Active, Non-Intrusive Inspection Technologies for Homeland Defense (open access)

Active, Non-Intrusive Inspection Technologies for Homeland Defense

Active, non-intrusive inspection or interrogation technologies have been used for 100 years - with the primary focus being radiographic imaging. During the last 50 years, various active interrogation systems have been investigated and most have revealed many unique and interesting capabilities and advantages that have already benefited the general public. Unfortunately, except for medical and specific industrial applications, these unique capabilities have not been widely adopted, largely due to the complexity of the technology, the overconfident reliance on passive detection systems to handle most challenges, and the unrealistic public concerns regarding radiation safety issues for a given active inspection deployment. The unique homeland security challenges facing the United States today are inviting more "out-of-the-box" solutions and are demanding the effective technological solutions that only active interrogation systems can provide. While revolutionary new solutions are always desired, these technology advancements are rare, and when found, usually take a long time to fully understand and implement for a given application. What's becoming more evident is that focusing on under-developed, but well-understood, active inspection technologies can provide many of the needed "out-of-the-box" solutions. This paper presents a brief historical overview of active interrogation. It identifies some of the major homeland defense challenges being …
Date: June 1, 2003
Creator: Jones, James L.
System: The UNT Digital Library
Advances in lithium-ion batteries (open access)

Advances in lithium-ion batteries

The editors state in their introduction that this book is intended for lithium-ion scientists and engineers but they hope it may be of interest to scientists from other fields. Their main aim was to provide a snapshot of the state of the Lithium-ion art and in this they have largely succeeded. The book is comprised of a collection of very current reviews of the lithium ion battery literature by acknowledged experts that draw heavily on the authors' own research but are sufficiently general to provide the lithium ion researcher with enough guidance to the current literature and the current thinking in the field. Some of the literature references may be too current as there are numerous citations of conference proceedings which may be easily accessible to the lithium ion scientist or engineer but are not likely to be available to the interested chemist coming to the field for the first time. One author expresses the hope and expectation that properly peer-reviewed articles will appear in due course and the interested reader should look out for them in future. From the point of view of the lithium ion battery scientist and engineer, the book covers most of the topics that are …
Date: June 24, 2003
Creator: Kerr, John B.
System: The UNT Digital Library
Analysis of the b2 correction in the Tevatron (open access)

Analysis of the b2 correction in the Tevatron

Beam loss and emittance dilution during ramping from injection to collision energy is observed in the Tevatron, now in its collider run-II stage. It is well known that the sextupole (b2) components in the superconducting dipole magnets decay during the injection plateau and snap back rapidly at the start of the ramp. These so called dynamic effects, which were originally discovered in the Tevatron, are compensated with the chromaticity correctors, distributed around the ring. Imperfect control of the chromaticity during injection and snapback can contribute to the beam loss. Therefore a thorough investigation of the b2 compensation in the Tevatron was launched, including beam chromaticity measurements and offline magnetic measurements on Tevatron dipoles. This paper reports the status of this investigation. A companion paper describes in detail the results of the magnet measurements. This work was partly conducted as a collaboration between FNAL and CERN.
Date: June 10, 2003
Creator: al., Pierre Bauer et
System: The UNT Digital Library
Antiproton acceleration in the Fermilab Main Injector using 2.5 MHz (H=28) and 53 MHz (H=588) rf systems (open access)

Antiproton acceleration in the Fermilab Main Injector using 2.5 MHz (H=28) and 53 MHz (H=588) rf systems

During the Run II era at Fermilab, the Recycler stores antiprotons at 8 GeV and the Main Injector accelerates the antiprotons and the protons from 8 GeV to 150 GeV for Tevatron injection. The Recycler injects antiprotons to the Main Injector in 2.5 MHz rf buckets. This report presents an acceleration scheme for the antiprotons that involves a slow ramp with initial 2.5 MHz acceleration and subsequent fast acceleration with 53 MHz rf system. Beam acceleration and rf manipulation with space charge and beam loading effects are simulated using the longitudinal simulation code ESME. Simulation suggests that one can expect about 15% emittance growth for the entire acceleration cycle with beam loading compensations. Preliminary experimental results with proton beam will also be presented.
Date: June 10, 2003
Creator: al., Vincent Wu et
System: The UNT Digital Library
Antiproton stacking and un-stacking in the Fermilab Recycler Ring (open access)

Antiproton stacking and un-stacking in the Fermilab Recycler Ring

The Fermilab Recycler Ring (RR) is intended to be used as a future antiproton storage ring for the Run II proton-antiproton collider operation. It is proposed that about 40mA of antiproton beam from the Accumulator Ring will be transferred to the Recycler once for every two to three hours, stacked and cooled. This operation continues for about 10 to 20 hours depending on the collider needs for antiprotons. Eventually, the cooled antiproton beam will be un-stacked from the Recycler and transferred to the Tevatron via the Main Injector. They have simulated stacking and un-stacking of antiprotons in the Recycler using multi-particle beam dynamics simulation code ESME. In this paper they present results of these simulations.
Date: June 12, 2003
Creator: Bhat, Chandra
System: The UNT Digital Library
Antiproton stacking in the Recycler (open access)

Antiproton stacking in the Recycler

Possibilities to accumulate antiprotons in the Recycler are considered for three different cases: with current stochastic cooling, with upgraded stochastic cooling and with electron cooling. With stochastic cooling only, even upgraded, Recycler looks hardly useful. However, with electron cooling at its goal parameters and reasonably good vacuum in the Recycler, this machine would be efficient.
Date: June 23, 2003
Creator: Burov, Alexey
System: The UNT Digital Library
Aperture limitations for 2nd generation Nb3Sn LHC IR quadrupoles (open access)

Aperture limitations for 2nd generation Nb3Sn LHC IR quadrupoles

One of the straightforward ways towards the higher luminosity in the LHC is a replacement of the present 70-mm NbTi quadrupoles with Nb{sub 3}Sn quadrupoles which would provide the same field gradient but in a larger aperture. Conceptual designs of such quadrupoles with 90 mm aperture have been developed and studied. This paper discusses the possibilities and limitations of increasing the aperture of Nb{sub 3}Sn low-beta quadrupoles for a LHC luminosity upgrade up to 110 mm.
Date: June 2, 2003
Creator: Zlobin, Alexander V.; Kashikhin, Vadim V. & Strait, James B.
System: The UNT Digital Library
Assessing the Proliferation Resistance of Innovative Nuclear Fuel Cycles (open access)

Assessing the Proliferation Resistance of Innovative Nuclear Fuel Cycles

The National Nuclear Security Administration is developing methods for nonproliferation assessments to support the development and implementation of U.S. nonproliferation policy. This paper summarizes the key results of that effort. Proliferation resistance is the degree of difficulty that a nuclear material, facility, process, or activity poses to the acquisition of one or more nuclear weapons. A top-level measure of proliferation resistance for a fuel cycle system is developed here from a hierarchy of metrics. At the lowest level, intrinsic and extrinsic barriers to proliferation are defined. These barriers are recommended as a means to characterize the proliferation characteristics of a fuel cycle. Because of the complexity of nonproliferation assessments, the problem is decomposed into: metrics to be computed, barriers to proliferation, and a finite set of threats. The spectrum of potential threats of nuclear proliferation is complex and ranges from small terrorist cells to industrialized countries with advanced nuclear fuel cycles. Two general categories of methods have historically been used for nonproliferation assessments: attribute analysis and scenario analysis. In the former, attributes of the systems being evaluated (often fuel cycle systems) are identified that affect their proliferation potential. For a particular system under consideration, the attributes are weighted subjectively. In …
Date: June 23, 2003
Creator: Bari, R.; Roglans, J.; Denning, R. & Mladineo, S.
System: The UNT Digital Library
Atomic resolution of lithium ions in LiCoO{sub 2} (open access)

Atomic resolution of lithium ions in LiCoO{sub 2}

LiCoO{sub 2} is the most common lithium storage material used as positive electrode in lithium rechargeable batteries. Ordering of lithium and vacancies has a profound effect on the physical properties of Li{sub x}CoO{sub 2} and the electrochemical performances of lithium batteries. An exit surface wave (ESW) phase image reconstructed from experimental images obtained on the LBNL One-Angstrom Microscope (OAM) shows all three types of atoms in LiCoO{sub 2}.
Date: June 5, 2003
Creator: Shao-Horn, Yang; Croguennec, Laurence; Delmas, Claude; Nelson, E. Chris & O'Keefe, Michael A.
System: The UNT Digital Library
Automated Batch Characterization of Icf Shells With Vision-Enabled Optical Microscope System (open access)

Automated Batch Characterization of Icf Shells With Vision-Enabled Optical Microscope System

OAK-B135 Inertial Confinement Fusion (ICF) shells are mesoscale objects with nano-scale dimensional and nano-surface finish requirements. Currently, the shell dimensions are measured by white-light interferometry and an image analysis method. These two methods complement each other and give a rather complete data set on a single shell. The process is, however, labor intensive. They have developed an automation routine to fully characterize a shell in one shot and perform unattended batch measurements. The method is useful to the ICF program both for production screening and for full characterization. It also has potential for Inertial Fusion Energy (IFE) power plant where half a million shells need to be processed daily.
Date: June 1, 2003
Creator: Huang, H.; Stephens, R. B.; Hill, D. W.; Lyon, C.; Nikroo, A. & Steinman, D. A.
System: The UNT Digital Library
The AWM-SIAM Sonia Kovalesvky Lecture - 3 part Lecture Series (open access)

The AWM-SIAM Sonia Kovalesvky Lecture - 3 part Lecture Series

The Association for Women in Mathematics (AWM) in cooperation with the Society for Industrial and Applied Mathematics (SIAM) and with funding from the Department of Energy initiated a new lecture series. The purpose of the lecture series is to increase the visibility of women who have made significant contributions in applied or computational mathematics. The AWM-SIAM Sonia Kovalevsky Lecture is presented at the SIAM Annual Meeting which is a national conference. The lecturer is a woman who has made distinguished contributions in applied or computational mathematics. The lecturer is determined by the Selection Committee which consists of two members of AWM and two members of SIAM, appointed by the presidents of these organizations. The committee may solicit nominations from other members of the scientific and engineering community. The lectureship may be awarded to any woman in the scientific or engineering community.
Date: June 3, 2003
Creator: Lenhart, Suzanne & Lewis, Jennifer
System: The UNT Digital Library
B physics at CDF (open access)

B physics at CDF

B physics is at the core of the CDF agenda for Run II. With the Tevatron performance gradually improving, samples of data corresponding to about 70 pb{sup -1} are now available. Due to improved detector capabilities these data already allow one to improve a number of Run I results, as well as perform a series of new measurements. We present an overview of the current state of B physics at CDF.
Date: June 4, 2003
Creator: Anikeev, K.
System: The UNT Digital Library
Barrier RF stacking at Fermilab (open access)

Barrier RF stacking at Fermilab

A key issue to upgrade the luminosity of the Tevatron Run2 program and to meet the neutrino requirement of the NuMI experiment at Fermilab is to increase the proton intensity on the target. This paper introduces a new scheme to double the number of protons from the Main Injector (MI) to the pbar production target (Run2) and to the pion production target (NuMI). It is based on the fact that the MI momentum acceptance is about a factor of four larger than the momentum spread of the Booster beam. Two RF barriers--one fixed, another moving--are employed to confine the proton beam. The Booster beams are injected off-momentum into the MI and are continuously reflected and compressed by the two barriers. Calculations and simulations show that this scheme could work provided that the Booster beam momentum spread can be kept under control. Compared with slip stacking, a main advantage of this new method is small beam loading effect thanks to the low peak beam current. The RF barriers can be generated by an inductive device, which uses nanocrystal magnet alloy (Finemet) cores and fast high voltage MOSFET switches. This device has been designed and fabricated by a Fermilab-KEK-Caltech team. The first …
Date: June 4, 2003
Creator: al., Weiren Chou et
System: The UNT Digital Library
Beam dynamics simulations for the Fermilab Recycler Ring barrier buckets (open access)

Beam dynamics simulations for the Fermilab Recycler Ring barrier buckets

The Recycler Ring (RR) is an 8 GeV pbar storage ring for future ppbar collider operations at Fermilab. By design, the beam in the Recycler is stored in three segments (hot, cold and newly transferred beam) azimuthally, using barrier buckets. Properties of the beam in the Recycler are found to be affected by stray magnetic field caused by the Main Injector acceleration ramping process. Here we present results of our measurements of the longitudinal emittance growth of the beam in the Recycler Ring due to the Main Injector ramp and the results of model simulation of this effect using a multi-particle beam dynamics simulation program (ESME).
Date: June 2, 2003
Creator: al., H. Kang et
System: The UNT Digital Library
Beam losses at injection energy and during acceleration in the Tevatron (open access)

Beam losses at injection energy and during acceleration in the Tevatron

Protons and anti-protons circulate on helical orbits in the Tevatron. At injection energy (150 GeV) the lifetimes of both species are significantly lower on the helical orbits compared to lifetimes on the central orbit but for different reasons. There are also significant beam losses in both beams when they are accelerated to top energy (980 GeV) again for different reasons. They report on experimental studies to determine the reasons and on methods of improving the lifetimes and losses for both beams.
Date: June 2, 2003
Creator: al., Tanaji Sen et
System: The UNT Digital Library
A Binary Segmentation Approach for Boxing Ribosome Particles in Cryo EM Micrographs (open access)

A Binary Segmentation Approach for Boxing Ribosome Particles in Cryo EM Micrographs

Three-dimensional reconstruction of ribosome particles from electron micrographs requires selection of many single-particle images. Roughly 100,000 particles are required to achieve approximately 10 angstrom resolution. Manual selection of particles, by visual observation of the micrographs on a computer screen, is recognized as a bottleneck in automated single particle reconstruction. This paper describes an efficient approach for automated boxing of ribosome particles in micrographs. Use of a fast, anisotropic non-linear reaction-diffusion method to pre-process micrographs and rank-leveling to enhance the contrast between particles and the background, followed by binary and morphological segmentation constitute the core of this technique. Modifying the shape of the particles to facilitate segmentation of individual particles within clusters and boxing the isolated particles is successfully attempted. Tests on a limited number of micrographs have shown that over 80 percent success is achieved in automatic particle picking.
Date: June 24, 2003
Creator: Adiga, Umesh P. S.; Malladi, Ravi; Baxter, William & Glaeser, Robert M.
System: The UNT Digital Library
Bioactive glass coatings for orthopedic metallic implants (open access)

Bioactive glass coatings for orthopedic metallic implants

The objective of this work is to develop bioactive glass coatings for metallic orthopedic implants. A new family of glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate coatings on Ti-based and Co-Cr alloys have been determined and related to the glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, glass coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.
Date: June 30, 2003
Creator: Lopez-Esteban, Sonia; Saiz, Eduardo; Fujino, Sigheru; Oku, Takeo; Suganuma, Katsuaki & Tomsia, Antoni P.
System: The UNT Digital Library
Bottom and charm masses and lifetimes at the Tevatron; and a pentaquark search (open access)

Bottom and charm masses and lifetimes at the Tevatron; and a pentaquark search

The Fermilab Tevatron, operating at {radical}s = 1.96 TeV, provides a rich environment for the study of the bottom and charmed hadrons and for searches of other bound states. Presented here are recent measurements of the masses of the following states using fully reconstructed events: B{sup +}, B{sup 0}, B{sub s}, {Lambda}{sub b}, and the neutral B**. Lifetimes from both CDF and D0 in exclusive decays for all of these modes are also presented (sans the B**). A search was conducted at CDF for the {Xi}{sup 2} and {Xi}{sup 0} pentaquark states in the decay {Xi}(1860) {yields} {Xi}{sup -} {pi}{sup {+-}} setting a limit on their production in p-{bar p} collisions relative to the number of {Xi}(1530) baryons seen.
Date: June 9, 2003
Creator: Huffman, B. Todd
System: The UNT Digital Library
Bs physics and prospects at the Tevatron (open access)

Bs physics and prospects at the Tevatron

Both experiments CDF and D0 at the Tevatron collider have now the first samples of B{sub s} where preliminary measurements are performed. The mass and lifetime determination is shown and the yield for the hadronic B{sub s} decays, the first step towards the B{sub s} production fraction and Branching Ratio, is discussed. This also sets the bases for a re-evaluation of mixing capabilities in Run II.
Date: June 16, 2003
Creator: Lucchesi, D.
System: The UNT Digital Library
The BTeV pixel and microstrip detector (open access)

The BTeV pixel and microstrip detector

The BTeV pixel detector is one of the most crucial elements in the BTeV experiment. While the pixel detector is technically challenging, we have made great progress towards identifying viable solutions for individual components of the system. The forward silicon tracker is based on more mature technology and its design has benefited from the experience of other experiments. Nevertheless, we have started an R&D program on the forward silicon tracker and first results are expected some time next year.
Date: June 4, 2003
Creator: Kwan, Simon W
System: The UNT Digital Library
Calibration Tools for Measurement of Highly Enriched Uranium in Oxide and Mixed Uranium-Plutonium Oxide with a Passive-Active Neutron Drum Shuffler (open access)

Calibration Tools for Measurement of Highly Enriched Uranium in Oxide and Mixed Uranium-Plutonium Oxide with a Passive-Active Neutron Drum Shuffler

Lawrence Livermore National Laboratory (LLNL) has completed an extensive effort to calibrate the LLNL passive-active neutron drum (PAN) shuffler (Canberra Model JCC-92) for accountability measurement of highly enriched uranium (HEU) oxide and HEU in mixed uranium-plutonium (U-Pu) oxide. Earlier papers described the PAN shuffler calibration over a range of item properties by standards measurements and an extensive series of detailed simulation calculations. With a single normalization factor, the simulations agree with the HEU oxide standards measurements to within {+-}1.2% at one standard deviation. Measurement errors on mixed U-Pu oxide samples are in the {+-}2% to {+-}10% range, or {+-}20 g for the smaller items. The purpose of this paper is to facilitate transfer of the LLNL procedure and calibration algorithms to external users who possess an identical, or equivalent, PAN shuffler. Steps include (1) measurement of HEU standards or working reference materials (WRMs); (2) MCNP simulation calculations for the standards or WRMs and a range of possible masses in the same containers; (3) a normalization of the calibration algorithms using the standard or WRM measurements to account for differences in the {sup 252}Cf source strength, the delayed-neutron nuclear data, effects of the irradiation protocol, and detector efficiency; and (4) a …
Date: June 13, 2003
Creator: Mount, M.; O'Connell, W.; Cochran, C. & Rinard, P.
System: The UNT Digital Library