2005 Atomic Physics Gordon Conference, June 26-July 1, 2005 (open access)

2005 Atomic Physics Gordon Conference, June 26-July 1, 2005

This article is a detailed description of the Gordon Research Conference on Atomic Physics.
Date: June 25, 2005
Creator: Monroe, Christopher
System: The UNT Digital Library
2010 INORGANIC CHEMISTRY GORDON RESEARCH CONFERENCE JUNE 20 - 25, 2010 (open access)

2010 INORGANIC CHEMISTRY GORDON RESEARCH CONFERENCE JUNE 20 - 25, 2010

The Inorganic Chemistry GRC is one of the longest-standing of the GRCs, originating in 1951. Over the years, this conference has played a role in spawning many other GRCs in specialized fields, due to the involvement of elements from most of the periodic table. These include coordination, organometallic, main group, f-element, and solid state chemistries; materials science, catalysis, computational chemistry, nanotechnology, bioinorganic, environmental, and biomedical sciences just to name a few. The 2010 Inorganic Chemistry GRC will continue this tradition, where scientists at all levels from academic, industrial, and national laboratories meet to define the important problems in the field and to highlight emerging opportunities through exchange of ideas and discussion of unpublished results. Invited speakers will present on a wide variety of topics, giving attendees a look at areas both inside and outside of their specialized areas of interest. In addition to invited speakers, the poster sessions at GRCs are a key feature of the conference. All conferees at the Inorganic Chemistry GRC are invited to present a poster on their work, and here the informal setting promotes the free exchange of ideas and fosters new relationships. As in previous years, we will offer poster presenters the opportunity to …
Date: June 25, 2010
Creator: LOCKEMEYER, JOHN
System: The UNT Digital Library
Absolute Measurement of the Polarization of High Energy Proton Beams at RHIC (open access)

Absolute Measurement of the Polarization of High Energy Proton Beams at RHIC

The spin physics program at the Relativistic Heavy Ion Collider (RHIC) requires knowledge of the beam polarization to better than 5%. Such a goal is made the more difficult by the lack of knowledge of the analyzing power of high energy nuclear physics processes. To overcome this, a polarized hydrogen jet target was constructed and installed at one intersection region in RHIC where it intersects both beams and utilizes the precise knowledge of the jet atomic hydrogen beam polarization to measure the analyzing power in proton-proton elastic scattering in the Nuclear Coulomb Interference (CNI) region at the prescribed RHIC proton beam energy. The reverse reaction is used to assess the absolute beam polarization. Simultaneous measurements taken with fast high statistics polarimeters that measure the p-Carbon elastic scattering process also in the CNI region use the jet results to calibrate the latter.
Date: June 25, 2007
Creator: Makdisi, Y.; Bravar, A. Bunce, G. Gill, R.; Huang, H. & AL., ET
System: The UNT Digital Library
Accelerating Polarized Protons to 250 GEV (open access)

Accelerating Polarized Protons to 250 GEV

The Relativistic Heavy Ion Collider (RHIC) as the first high energy polarized proton collider was designed t o provide polarized proton collisions a t a maximum beam energy of 250 GeV. I t has been providing collisions a t a beam energy of 100 Gel' since 2001. Equipped with two full Siberian snakes in each ring, polarization is preserved during the acceleration from injection to 100 GeV with careful control of the betatron tunes and the vertical orbit distortions. However, the intrinsic spin resonances beyond 100 GeV are about a factor of two stronger than those below 100 GeV? making it important t o examine the impact of these strong intrinsic spin resonances on polarization survival and the tolerance for vertical orbit distortions. Polarized protons were accelerated t o the record energy of 250 GeV in RHIC with a polarization of 46% measured a t top energy in 2006. The polarization measurement as a function of beam energy also shows some polarization loss around 136 GeV, the first strong intrinsic resonance above 100 GeV. This paper presents the results and discusses the sensitivity of the polarization survival t o orbit distortions.
Date: June 25, 2007
Creator: Bai, M.; Ahrens, L.; Alekseev, I. G.; Alessi, J.; Beebe-Wang, J. & AL., ET
System: The UNT Digital Library
Acceleration of Electrons With the Racetrack Non-Scaling Ffag for E-Rhic (open access)

Acceleration of Electrons With the Racetrack Non-Scaling Ffag for E-Rhic

The future relativistic electron hadron collider: e-RHIC requires acceleration of electrons to 10 GeV. In the case that the super conducting linac is selected for acceleration, an energy recovery scheme is required. We propose to study a possibility of using the non-scaling Fixed-Field Gradient-Accelerator (NS-FFAG) for different energies. The beam will be accelerated by the superconducting linac at the top of the sine function, brought back to the front of the linac by the non-scaling FFAG and repeating this few times until the total energy of 20 GeV is reached. After collisions the beam is brought back by the non-scaling FFAG and decelerated (on the lower RF phase) in the same sequence but in the reverse order. Conventional and non-conventional beam dynamic issues will be discussed, like the transit time matching effect and the time of flight adjustments.
Date: June 25, 2007
Creator: Trbojevic, D.; Blaskiewicz, M.; Litvinenko, V.; Ptitsyn, V. & Roser, T.
System: The UNT Digital Library
The adaptive x-ray optics project at the Lawrence Livermore National Laboratory (open access)

The adaptive x-ray optics project at the Lawrence Livermore National Laboratory

None
Date: June 25, 2013
Creator: Pardini, T; Poyneer, L A; McCarville, T J; Macintosh, B; Bauman, B & Pivovaroff, M J
System: The UNT Digital Library
Aerial oxidation of tetraethyl silicate and effect on ammonia catalyzed hydrolysis (open access)

Aerial oxidation of tetraethyl silicate and effect on ammonia catalyzed hydrolysis

Colloidal suspensions of Si0{sub 2} in ethanol prepared by the ammonia catalyzed hydrolysis of tetraethyl silicate (TEOS) in ethanol have been routinely used for over 10 years to prepare antireflective (AR) coatings on the fused silica transmissive optical components of high power fusion lasers. Very high purity coatings are required to avoid laser damage and these are obtained when the TEOS is fractionally distilled under N{sub 2} prior to use. Recently we found that products from aerial oxidation of distilled TEOS, had a significant effect on the particle size of our coating suspensions to the detriment of the optical performance. We require particle sizes less than 20 nm to avoid light loss due to scatter and contaminated TEOS gave suspensions with much higher particle sizes. Oxidation products were identified by GC mass spectroscopy and included acetaldehyde, acetic acid, silicon acetates and reaction products of these compounds with ethanol. Acetic acid and silicon acetates were found to be the major cause of large particle formation. These could be removed by careful redistillation preferably in the presence of a small quantity of magnesium ethoxide. Storage in sealed containers over N{sub 2} avoided further problems.
Date: June 25, 1997
Creator: Thomas, I. M.
System: The UNT Digital Library
Anaerobic, Nitrate-Dependent Oxidation of U(IV) Oxide Minerals by the Chemolithoautotrophic Bacterium Thiobacillus denitrificans (open access)

Anaerobic, Nitrate-Dependent Oxidation of U(IV) Oxide Minerals by the Chemolithoautotrophic Bacterium Thiobacillus denitrificans

Under anaerobic conditions and at circumneutral pH, cells of the widely-distributed, obligate chemolithoautotrophic bacterium Thiobacillus denitrificans oxidatively dissolved synthetic and biogenic U(IV) oxides (uraninite) in nitrate-dependent fashion: U(IV) oxidation required the presence of nitrate and was strongly correlated to nitrate consumption. This is the first report of anaerobic U(IV) oxidation by an autotrophic bacterium.
Date: June 25, 2004
Creator: Beller, H R
System: The UNT Digital Library
Analysis and Simulation of Main Magnet Transmission Line Effect (open access)

Analysis and Simulation of Main Magnet Transmission Line Effect

A main magnet chain forms a pair of transmission lines. Pulse-reflection-caused voltage and current differentiation throughout the magnet chain can have adverse effect on main magnet field quality. This effect is associated with magnet system configuration, coupling efficiency, and parasitic parameters. A better understanding of this phenomenon will help us in new design and existing system upgrade. In this paper, we exam the transmission line effect due to different input functions as well as configuration, coupling, and other parameters.
Date: June 25, 2007
Creator: Zhang, W.; Marneris, I. & Sandberg, J.
System: The UNT Digital Library
Analysis of the ATW fuel cycle using the REBUS-3 code system. (open access)

Analysis of the ATW fuel cycle using the REBUS-3 code system.

Partitioning and transmutation strategies are under study in several countries as a means of reducing the long-term hazards of spent fuel and other high-level nuclear waste. Various reactor and accelerator-driven system concepts have been proposed to transmute the long-lived radioactive nuclei of waste into stable or short-lived species. Among these concepts, the accelerator-driven transmutation of waste (ATW) system has been proposed by LANL for rapid destruction of transuranic actinides and long-lived fission products ({sup 99}Tc and {sup 129}I).The current reference ATW concept employs a subcritical, liquid metal cooled, fast-spectrum nuclear subsystem. Because the discharged fuel is recycled, analysis of ATW nuclear performance requires modeling of the external cycle as well as the in-core fuel management. The fuel cycle analysis of ATW can be performed rigorously using Monte Carlo calculations coupled with detailed depletion calculations. However, the inefficiency of this approach makes it impractical, particularly in view of (a) the large number of fuel cycle calculations needed for design optimization and (b) the need to represent complex in-core and out-of-core fuel cycle operations. To meet the need for design-oriented capabilities, tools previously developed for fast reactor calculations are being adapted for application to ATW. Here we describe the extension and application …
Date: June 25, 1999
Creator: Khalil, H. S. & Yang, W. S.
System: The UNT Digital Library
Ash cloud aviation advisories (open access)

Ash cloud aviation advisories

During the recent (12--22 June 1991) Mount Pinatubo volcano eruptions, the US Air Force Global Weather Central (AFGWC) requested assistance of the US Department of Energy`s Atmospheric Release Advisory Capability (ARAC) in creating volcanic ash cloud aviation advisories for the region of the Philippine Islands. Through application of its three-dimensional material transport and diffusion models using AFGWC meteorological analysis and forecast wind fields ARAC developed extensive analysis and 12-hourly forecast ash cloud position advisories extending to 48 hours for a period of five days. The advisories consisted of ``relative`` ash cloud concentrations in ten layers (surface-5,000 feet, 5,000--10,000 feet and every 10,000 feet to 90,000 feet). The ash was represented as a log-normal size distribution of 10--200 {mu}m diameter solid particles. Size-dependent ``ashfall`` was simulated over time as the eruption clouds dispersed. Except for an internal experimental attempt to model one of the Mount Redoubt, Alaska, eruptions (12/89), ARAC had no prior experience in modeling volcanic eruption ash hazards. For the cataclysmic eruption of 15--16 June, the complex three-dimensional atmospheric structure of the region produced dramatically divergent ash cloud patterns. The large eruptions (> 7--10 km) produced ash plume clouds with strong westward transport over the South China Sea, Southeast …
Date: June 25, 1992
Creator: Sullivan, T. J.; Ellis, J. S.; Schalk, W. W. & Nasstrom, J. S.
System: The UNT Digital Library
Beam-Based Sextupole Polarity Verification in the RHIC (open access)

Beam-Based Sextupole Polarity Verification in the RHIC

This article presents a beam-based method to check RHIC arc sextupole polarities using local horizontal orbit three-bumps at injection energy. We use 11 bumps in each arc, each covering two SFs (focusing sextupoles) and one SD (defocusing sextupole). If there are no wrong sextupole polarities, the tune shifts from bump to bump and the tune shift patterns from arc to arc should be similar. Wrong sextupole polarities can be easily identified from mismatched signs or amplitudes of tune shifts from bump to bump and/or from arc to arc. Tune shifts in both planes during this study were tracked with a high-resolution base-band tunemeter (BBQ) system. This method was successfully used to the sextupole polarity check in RHIC Blue and Yellow rings in the RHIC 2006 and 2007 runs.
Date: June 25, 2007
Creator: Luo, Y.; Satogata, T.; Cameron, P.; Dellapenna, A. & Trbojevic, D.
System: The UNT Digital Library
Bpm Calibration Independent Lhc Optics Correction (open access)

Bpm Calibration Independent Lhc Optics Correction

The tight mechanical aperture for the LHC imposes severe constraints on both the beta and dispersion beating. Robust techniques to compensate these errors are critical for operation of high intensity beams in the LHC. We present simulations using realistic errors from magnet measurements and alignment tolerances in the presence of BPM noise. Correction reveals that the use of BPM calibration and model independent observables are key ingredients to accomplish optics correction. Experiments at RHIC to verify the algorithms for optics correction are also presented.
Date: June 25, 2007
Creator: Calaga, R.; Tomas, R.; Giovannozzi, M. & Zimmermann, F.
System: The UNT Digital Library
Carbon Nanotube Based Microfluidic Elements for Filtration and Concentration (open access)

Carbon Nanotube Based Microfluidic Elements for Filtration and Concentration

We have developed a method for integration of patterned arrays of carbon nanotubes or the ''nanotube mesh'' into microfabricated channels. The method includes standard lithographic methods for patterning and etching the substrate, followed by catalyst patterning, CVD deposition of nanotubes, and anodic bonding of coverslip top. We will describe a carbon nanotube filtering device fabricated using this method and discuss the use of carbon nanotube arrays as molecular concentration and separation media.
Date: June 25, 2003
Creator: Bakajin, O; Ben-Barak, N; Peng, J & Noy, A
System: The UNT Digital Library
CHALLENGES ENCOUNTERED DURING THE PROCESSING OF THE BNL ERL 5 CELL ACCELERATING CAVITY (open access)

CHALLENGES ENCOUNTERED DURING THE PROCESSING OF THE BNL ERL 5 CELL ACCELERATING CAVITY

One of the key components for the Energy Recovery Linac being built by the Electron cooling group in the Collider Accelerator Department is the 5 cell accelerating cavity which is designed to accelerate 2 MeV electrons from the gun up to 15-20 MeV, allow them to make one pass through the ring and then decelerate them back down to 2 MeV prior to sending them to the dump. This cavity was designed by BNL and fabricated by AES in Medford, NY. Following fabrication it was sent to Thomas Jefferson Lab in VA for chemical processing, testing and assembly into a string assembly suitable for shipment back to BNL for integration into the ERL. The steps involved in this processing sequence will be reviewed and the deviations from processing of similar SRF cavities will be discussed. The lessons learned from this process are documented to help future projects where the scope is different from that normally encountered.
Date: June 25, 2007
Creator: Burrill, A.
System: The UNT Digital Library
Collaboratory for support of scientific research (open access)

Collaboratory for support of scientific research

Collaboration is an increasingly important aspect of magnetic fusion energy research. With the increased size and cost of experiments needed to approach reactor conditions, the numbers being constructed has become limited. In order to satisfy the desire for many groups to conduct research on these facilities, we have come to rely more heavily on collaborations. Fortunately, at the same time, development of high performance computers and fast and reliable wide area networks has provided technological solutions necessary to support the increasingly distributed work force without the need for relocation of entire research staffs. Development of collaboratories, collaborative or virtual laboratories, is intended to provide the capability needed to interact from afar with colleagues at multiple sites. These technologies are useful to groups interacting remotely during experimental operations as well as to those involved in the development of analysis codes and large scale simulations The term ``collaboratory`` refers to a center without walls in which researchers can perform their studies without regard to geographical location - interacting with colleagues, accessing instrumentation, sharing data and computational resources, and accessing information from digital libraries [1],[2]. While it is widely recognized that remote collaboration is not a universal replacement for personal contact, it does …
Date: June 25, 1998
Creator: Casper, T. A.; Meyer, W. H. & Moller, J. M.
System: The UNT Digital Library
Collective Effects in the NSLS-II Storage Ring. (open access)

Collective Effects in the NSLS-II Storage Ring.

A new high-brightness synchrotron light source (NSLS-II) is under design at BNL. The 3-GeV NSLS-II storage ring has a double-bend achromatic lattice with damping wigglers installed in zero-dispersion straights to reduce the emittance below 1nm. In this paper, we present an overview of the impact of collective effects upon the performance of the storage ring. Subjects discussed include instability thresholds, Touschek lifetime and intra-beam scattering.
Date: June 25, 2007
Creator: Krinsky, S.; Bengtsson, J.; Berg, J. S.; Blaskiewicz, M.; Blednykh, A.; Guo, W. et al.
System: The UNT Digital Library
Collective Effects in the Rhic-Ii Electron Cooler (open access)

Collective Effects in the Rhic-Ii Electron Cooler

Electron cooling at RHIC-I1 upgrade imposes strict requirements on the quality of the electron beam at the cooling section. Beam current dependent effects such as the space charge, wake fields, CSR in bending magnets, trapped ions, etc., will tend to spoil the beam quality and decrease the cooling efficiency. In this paper, we estimate the defocusing effect of the space charge at the cooling section and describe our plan to compensate the defocusing space charge force by focusing solenoids. We also estimate the energy and emittance growth cased by wake fields. Finally, we discuss ion trapping in the electron cooler and consider different techniques to minimize the effect of ion trapping.
Date: June 25, 2007
Creator: Pozdeyev, E.; Ben-Zvi, Ilan; Fedotov, A.; Kayran, D.; Litvinenko, V. & Wang, G.
System: The UNT Digital Library
Collective Effects in the SuperB Collider (open access)

Collective Effects in the SuperB Collider

Some collective effects have been studied for the SuperB high luminosity collider. Estimates of the effect of Intra Beam Scattering (IBS) on the emittance and energy spread growths have been carried up for both the High Energy (HER, positrons) and the Low Energy (LER, electrons) rings. Electron cloud build up simulations for HER were performed with the ECLOUD code, developed at CERN, to predict the cloud formation in the arcs, taking into account possible remediation techniques such as clearing electrodes. The new code CMAD, developed at SLAC, has been used to study the effect of this electron cloud on the beam and assess the thresholds above which the electron cloud instability would set in.
Date: June 25, 2012
Creator: Demma, Theo; /INFN, Rome & Pivi, Mauro
System: The UNT Digital Library
Colliding pulse injection experiments in non-collinear geometryfor controlled laser plasma wakefield acceleration of electrons (open access)

Colliding pulse injection experiments in non-collinear geometryfor controlled laser plasma wakefield acceleration of electrons

An optical injection scheme for a laser-plasma basedaccelerator which employs a non-collinear counter-propagating laser beamto push background electrons in the focusing and acceleration phase viaponderomotive beat with the trailing part of the wakefield driver pulseis discussed. Preliminary experiments were performed using a drive beamof a_0 = 2.6 and colliding beam of a_1 = 0.8 both focused on the middleof a 200 mu m slit jet backed with 20 bar, which provided ~; 260 mu mlong gas plume. The enhancement in the total charge by the collidingpulse was observed with sharp dependence on the delay time of thecolliding beam. Enhancement of the neutron yield was also measured, whichsuggests a generation of electrons above 10 MeV.
Date: June 25, 2007
Creator: Toth, Carl B.; Esarey, Eric H.; Geddes, Cameron G.R.; Leemans,Wim P.; Nakamura, Kei; Panasenko, Dmitriy et al.
System: The UNT Digital Library
Complete Genome Sequence of Coraliomargarita Akajimensis Type Strain (04OKA010-24T) (open access)

Complete Genome Sequence of Coraliomargarita Akajimensis Type Strain (04OKA010-24T)

Coraliomargarita akajimensis Yoon et al. 2007 the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium which was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis organism is of special interest because of its phylogenetic position in a genomically purely studied area in the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
Date: June 25, 2010
Creator: Mavromatis, Konstantinos; Abt, Birte; Brambilla, Evelyne; Lapidus, Alla; Copeland, Alex; Desphande, Shweta et al.
System: The UNT Digital Library
Complete Genome Sequence of Denitrovibrio Acetiphilus Type Strain (N2460T) (open access)

Complete Genome Sequence of Denitrovibrio Acetiphilus Type Strain (N2460T)

Denitrovibrio acetiphilus Myhr and Torsvik 2000 is the type species of the genus Denitrovibrio in the bacterial family Deferribacteraceae. It is of phylogenetic interest because there are only six genera described in the family Deferribacteraceae. D. acetiphilus was isolated as a representative of a population reducing nitrate to ammonia in a laboratory column simulating the conditions in off-shore oil recovery fields. When nitrate was added to this column undesirable hydrogen sulfide production was stopped because the sulfate reducing populations were superseded by these nitrate reducing bacteria. Here we describe the features of this marine, mesophilic, obligately anaerobic organism respiring by nitrate reduction, together with the complete genome sequence, and annotation. This is the second complete genome sequence of the order Deferribacterales and the class Deferribacteres, which is the sole class in the phylum Deferribacteres. The 3,222,077 bp genome with its 3,034 protein-coding and 51 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.
Date: June 25, 2010
Creator: Kiss, Hajnalka; Lang, Elke; Lapidus, Alla; Copeland, Alex; Nolan, Matt; Glavina Del Rio, Tijana et al.
System: The UNT Digital Library
A Complete Scheme for Ionization Cooling for a Muon Collider. (open access)

A Complete Scheme for Ionization Cooling for a Muon Collider.

A complete scheme for production and cooling a muon beam for three specified muon colliders is presented. Parameters for these muon colliders are given. The scheme starts with the front end of a proposed neutrino factory that yields bunch trains of both muon signs. Emittance exchange cooling in slow helical lattices reduces the longitudinal emittance until it becomes possible to merge the trains into single bunches, one of each sign. Further cooling in all dimensions is applied to the single bunches in further slow helical lattices. Final transverse cooling to the required parameters is achieved in 50 T solenoids using high TC superconductor at 4 K. Preliminary simulations of each element are presented.
Date: June 25, 2007
Creator: Palmer, R. B.; Berg, J. S.; Fernow, R. C.; Gallardo, J. C.; Kirk, H. G.; Alexahin, Y. et al.
System: The UNT Digital Library
Conceptual Design of the NSLS-II Injection System. (open access)

Conceptual Design of the NSLS-II Injection System.

We present the conceptual design of the NSLS-II injection system [1,2]. The injection system consists of a low-energy linac, booster and transport lines. We review two different injection system configurations; a booster located in the storage ring tunnel and a booster housed in a separate building. We briefly discuss main parameters and layout of the injection system components.
Date: June 25, 2007
Creator: Shaftan, T.; Rose, T.; Pinayev, I.; Heese, R.; Bengtsson, J.; Skaritka, J. et al.
System: The UNT Digital Library