A VUV Photoionization Study of the Combustion-Relevant Reaction of the Phenyl Radical (C6H5) with Propylene (C3H6) in a High Temperature Chemical Reactor (open access)

A VUV Photoionization Study of the Combustion-Relevant Reaction of the Phenyl Radical (C6H5) with Propylene (C3H6) in a High Temperature Chemical Reactor

We studied the reaction of phenyl radicals (C6H5) with propylene (C3H6) exploiting a high temperature chemical reactor under combustion-like conditions (300 Torr, 1,200-1,500 K). The reaction products were probed in a supersonic beam by utilizing tunable vacuum ultraviolet (VUV) radiation from the Advanced Light Source and recording the photoionization efficiency (PIE) curves at mass-to-charge ratios of m/z = 118 (C9H10+) and m/z = 104 (C8H8+). Our results suggest that the methyl and atomic hydrogen losses are the two major reaction pathways with branching ratios of 86 10 percent and 14 10 percent. The isomer distributions were probed by fitting the recorded PIE curves with a linear combination of the PIE curves of the individual C9H10 and C8H8 isomers. Styrene (C6H5C2H3) was found to be the exclusive product contributing to m/z = 104 (C8H8+), whereas 3-phenylpropene, cis-1-phenylpropene, and 2-phenylpropene with branching ratios of 96 4 percent, 3 3 percent, and 1 1 percent could account for signal at m/z = 118 (C9H10+). Although searched for carefully, no evidence of the bicyclic indane molecule could be provided. The reaction mechanisms and branching ratios are explained in terms of electronic structure calculations nicely agreeing with a recent crossed molecular beam study on this …
Date: February 22, 2012
Creator: Manoa, University of Hawaii at; Laboratories, Sandia National; Zhang, Fangtong; Kaiser, Ralf I.; Golan, Amir; Ahmed, Musahid et al.
System: The UNT Digital Library
Detection of volatile organic compounds using surface enhanced Raman scattering (open access)

Detection of volatile organic compounds using surface enhanced Raman scattering

The authors present the detection of volatile organic compounds directly in their vapor phase by surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. The type of nanopillars is known as the tapered pillars. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of toluene vapor. The results show that SERS signal from a toluene vapor concentration of ppm level can be achieved, and the toluene vapor can be detected within minutes of exposing the SERS substrate to the vapor. A simple adsorption model is developed which gives results matching the experimental data. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors.
Date: March 22, 2012
Creator: Chang, A. S.; Maiti, A.; Ileri, N.; Bora, M.; Larson, C. C.; Britten, J. A. et al.
System: The UNT Digital Library
Generic Model Host System Design (open access)

Generic Model Host System Design

There are many simulation codes for accelerator modelling; each one has some strength but not all. A platform which can host multiple modelling tools would be ideal for various purposes. The model platform along with infrastructure support can be used not only for online applications but also for offline purposes. Collaboration is formed for the effort of providing such a platform. In order to achieve such a platform, a set of common physics data structure has to be set. Application Programming Interface (API) for physics applications should also be defined within a model data provider. A preliminary platform design and prototype is discussed.
Date: June 22, 2012
Creator: Chu, Chungming; Wu, Juhao; Qiang, Ji & Shen, Guobao
System: The UNT Digital Library
Studies of Space Charge Effects in the Proposed CERN PS2 (open access)

Studies of Space Charge Effects in the Proposed CERN PS2

A new proton synchrotron, the PS2, is under design study to replace the current proton synchrotron at CERN for the LHC upgrade. Nonlinear space charge effects could cause significant beam emittance growth and particle losses and limit the performance of the PS2. In this paper, we report on studies of the potential space-charge effects at the PS2 using three-dimensional self-consistent macroparticle tracking codes, IMPACT, MaryLie/IMPACT, and Synergia. We will present initial benchmark results among these codes. Effects of space-charge on the emittance growth, especially due to synchrotron coupling, aperture sizes, initial painted distribution, and RF ramping scheme will also be discussed.
Date: June 22, 2012
Creator: Qiang, Ji; Ryne, Robert; De Maria, Riccardo; Macridin, Alexandru; Spentzouris, Panagiotis; Papaphilippou, Yannis et al.
System: The UNT Digital Library
Heavy Quarkonium Production at LHC through W Boson Decays (open access)

Heavy Quarkonium Production at LHC through W Boson Decays

The production of the heavy (c{bar c})-quarkonium, (c{bar b})-quarkonium, and (b{bar b})-quarkonium states [({bar Q}') quarkonium for short], via the W{sup +} semi-inclusive decays, has been systematically studied within the framework of the nonrelativistic QCD. In addition to the two color-singlet S-wave states, we also discuss the production of the four color-singlet P-wave states |(Q{bar Q}')({sup 1}P{sub 1}){sub 1}> and |(Q{bar Q}')({sup 3}P{sub J}){sub 1}> [with J = (0,1,2)] together with the two color-octet components |(Q{bar Q}')({sup 1}S{sub 0}){sub 8}> and |(Q{bar Q}')({sup 3}S{sub 1}){sub 8}>. Improved trace technology is adopted to derive the simplified analytic expressions at the amplitude level, which shall be useful for dealing with the following cascade decay channels. At the LHC with the luminosity L {proportional_to} 10{sup 34} cm{sup -2} s{sup -1} and the center-of-mass energy {radical}S = 14 TeV, sizable heavy-quarkonium events can be produced through the W{sup +} boson decays; i.e., 2.57 x 10{sup 6} {eta}{sub c}, 2.65 x 10{sup 6} J/{Psi}, and 2.40 x 10{sup 6} P-wave charmonium events per year can be obtained, and 1.01 x 10{sup 5} B{sub c}, 9.11 x 10{sup 4} B*{sub c}, and 3.16 x 10{sup 4} P-wave (c{bar b})-quarkonium events per year can be obtained. Main …
Date: May 22, 2012
Creator: Liao, Qi-Li; U., /Chongqing; Wu, Xing-Gang; /SLAC, /Chongqing U.; Jiang, Jun; Yang, Zhi et al.
System: The UNT Digital Library
Award Nomination Information for Lawrence Livermore National Laboratory SkillSoft Perspectives Conference 2012 (open access)

Award Nomination Information for Lawrence Livermore National Laboratory SkillSoft Perspectives Conference 2012

None
Date: February 22, 2012
Creator: Positeri, L A & Molyneaux, B R
System: The UNT Digital Library
Breaking the Attosecond, Angstrom and TV/M Field Barriers with Ultra-Fast Electron Beams (open access)

Breaking the Attosecond, Angstrom and TV/M Field Barriers with Ultra-Fast Electron Beams

Recent initiatives at UCLA concerning ultra-short, GeV electron beam generation have been aimed at achieving sub-fs pulses capable of driving X-ray free-electron lasers (FELs) in single-spike mode. This use of very low Q beams may allow existing FEL injectors to produce few-100 attosecond pulses, with very high brightness. Towards this end, recent experiments at the LCLS have produced {approx}2 fs, 20 pC electron pulses. We discuss here extensions of this work, in which we seek to exploit the beam brightness in FELs, in tandem with new developments in cryogenic undulator technology, to create compact accelerator-undulator systems that can lase below 0.15 {angstrom}, or be used to permit 1.5 {angstrom} operation at 4.5 GeV. In addition, we are now developing experiments which use the present LCLS fs pulses to excite plasma wakefields exceeding 1 TV/m, permitting a table-top TeV accelerator for frontier high energy physics applications.
Date: June 22, 2012
Creator: Rosenzweig, James; Andonian, Gerard; Fukasawa, Atsushi; Hemsing, Erik; Marcus, Gabriel; Marinelli, Agostino et al.
System: The UNT Digital Library
Facts About XLDB-2011 (open access)

Facts About XLDB-2011

This note provides details of the 5th Extremely Large Databases Conference and Invitational Workshop that were held in 2011 on 18-19 October and 20 October, respectively, at the SLAC National Accelerator Laboratory in Menlo Park, California. The main goals of the conference were: (1) Encourage and accelerate the exchange of ideas between users trying to build extremely large databases worldwide and database solution providers; (2) Share lessons, trends, innovations, and challenges related to building extremely large databases; (3) Facilitate the development and growth of practical technologies for extremely large databases; and (4) Strengthen, expand, and engage the XLDB community.
Date: February 22, 2012
Creator: Becla, Jacek; Lim, Kian-Tat & Wang, Daniel L.
System: The UNT Digital Library
Functional Bounding Content Envelope for Type B Radioactive Material Transportation Packages (open access)

Functional Bounding Content Envelope for Type B Radioactive Material Transportation Packages

None
Date: May 22, 2012
Creator: Sitaraman, S.; Kim, S. & Anderson, B.
System: The UNT Digital Library
2012 CELLULAR & MOLECULAR FUNGAL BIOLOGY GORDON RESEARCH CONFERENCE, JUNE 17 - 22, 2012 (open access)

2012 CELLULAR & MOLECULAR FUNGAL BIOLOGY GORDON RESEARCH CONFERENCE, JUNE 17 - 22, 2012

The Gordon Research Conference on CELLULAR & MOLECULAR FUNGAL BIOLOGY was held at Holderness School, Holderness New Hampshire, June 17 - 22, 2012. The 2012 Gordon Conference on Cellular and Molecular Fungal Biology (CMFB) will present the latest, cutting-edge research on the exciting and growing field of molecular and cellular aspects of fungal biology. Topics will range from yeast to filamentous fungi, from model systems to economically important organisms, and from saprophytes and commensals to pathogens of plants and animals. The CMFB conference will feature a wide range of topics including systems biology, cell biology and morphogenesis, organismal interactions, genome organisation and regulation, pathogenesis, energy metabolism, biomass production and population genomics. The Conference was well-attended with 136 participants. Gordon Research Conferences does not permit publication of meeting proceedings.
Date: June 22, 2012
Creator: Berman, Judith
System: The UNT Digital Library
Management Of Hanford KW Basin Knockout Pot Sludge As Spent Nuclear Fuel (open access)

Management Of Hanford KW Basin Knockout Pot Sludge As Spent Nuclear Fuel

CH2M HILL Plateau Remediation Company (CHPRC) and AREVA Federal Services, LLC (AFS) have been working collaboratively to develop and deploy technologies to remove, transport, and interim store remote-handled sludge from the 10S-K West Reactor Fuel Storage Basin on the U.S. Department of Energy (DOE) Hanford Site near Richland, WA, USA. Two disposal paths exist for the different types of sludge found in the K West (KW) Basin. One path is to be managed as Spent Nuclear Fuel (SNF) with eventual disposal at an SNF at a yet to be licensed repository. The second path will be disposed as remote-handled transuranic (RH-TRU) waste at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. This paper describes the systems developed and executed by the Knockout Pot (KOP) Disposition Subproject for processing and interim storage of the sludge managed as SNF, (i.e., KOP material).
Date: October 22, 2012
Creator: Raymond, R. E. & Evans, K. M.
System: The UNT Digital Library
Reconstruction Algorithm for Point Source Neutron Imaging through Finite Thickness Scintillator (open access)

Reconstruction Algorithm for Point Source Neutron Imaging through Finite Thickness Scintillator

None
Date: January 22, 2012
Creator: Wang, H; Tang, V; McCarrick, J F & Moran, S
System: The UNT Digital Library
Micro-Analysis of Actinide Minerals for Nuclear Forensics and Treaty Verification (open access)

Micro-Analysis of Actinide Minerals for Nuclear Forensics and Treaty Verification

Micro-Raman spectroscopy has been demonstrated to be a viable tool for nondestructive determination of the crystal phase of relevant minerals. Collecting spectra on particles down to 5 microns in size was completed. Some minerals studied were weak scatterers and were better studied with the other techniques. A decent graphical software package should easily be able to compare collected spectra to a spectral library as well as subtract out matrix vibration peaks. Due to the success and unequivocal determination of the most common mineral false positive (zircon), it is clear that Raman has a future for complementary, rapid determination of unknown particulate samples containing actinides.
Date: March 22, 2012
Creator: M. Morey, M. Manard, R. Russo, G. Havrilla
System: The UNT Digital Library
2012 CHEMISTRY & PHYSICS OF GRAPHITIC CARBON MATERIALS GORDON RESEARCH CONFERENCE, JUNE 17-22, 2012 (open access)

2012 CHEMISTRY & PHYSICS OF GRAPHITIC CARBON MATERIALS GORDON RESEARCH CONFERENCE, JUNE 17-22, 2012

This conference will highlight the urgency for research on graphitic carbon materials and gather scientists in physics, chemistry, and engineering to tackle the challenges in this field. The conference will focus on scalable synthesis, characterization, novel physical and electronic properties, structure-properties relationship studies, and new applications of the carbon materials. Contributors
Date: June 22, 2012
Creator: Fertig, Herbert
System: The UNT Digital Library
Human Factors Engineering Program Review Model (NUREG-0711)Revision 3: Update Methodology and Key Revisions (open access)

Human Factors Engineering Program Review Model (NUREG-0711)Revision 3: Update Methodology and Key Revisions

The U.S. Nuclear Regulatory Commission (NRC) reviews the human factors engineering (HFE) programs of applicants for nuclear power plant construction permits, operating licenses, standard design certifications, and combined operating licenses. The purpose of these safety reviews is to help ensure that personnel performance and reliability are appropriately supported. Detailed design review procedures and guidance for the evaluations is provided in three key documents: the Standard Review Plan (NUREG-0800), the HFE Program Review Model (NUREG-0711), and the Human-System Interface Design Review Guidelines (NUREG-0700). These documents were last revised in 2007, 2004 and 2002, respectively. The NRC is committed to the periodic update and improvement of the guidance to ensure that it remains a state-of-the-art design evaluation tool. To this end, the NRC is updating its guidance to stay current with recent research on human performance, advances in HFE methods and tools, and new technology being employed in plant and control room design. NUREG-0711 is the first document to be addressed. We present the methodology used to update NUREG-0711 and summarize the main changes made. Finally, we discuss the current status of the update program and the future plans.
Date: July 22, 2012
Creator: Ohara J. M.; Higgins, J. & Fleger, S.
System: The UNT Digital Library
Lessons Re-learned: The Little Things (open access)

Lessons Re-learned: The Little Things

This slide show discusses: connector choices; polishing technique (manual vs. machine); fiber interconnect construction; and deployment of fiber in the field.
Date: October 22, 2012
Creator: Perez, C., Lewis, T.
System: The UNT Digital Library
Magnetic Fields in Population III Star Formation (open access)

Magnetic Fields in Population III Star Formation

We study the buildup of magnetic fields during the formation of Population III star-forming regions, by conducting cosmological simulations from realistic initial conditions and varying the Jeans resolution. To investigate this in detail, we start simulations from identical initial conditions, mandating 16, 32 and 64 zones per Jeans length, and studied the variation in their magnetic field amplification. We find that, while compression results in some amplification, turbulent velocity fluctuations driven by the collapse can further amplify an initially weak seed field via dynamo action, provided there is sufficient numerical resolution to capture vortical motions (we find this requirement to be 64 zones per Jeans length, slightly larger than, but consistent with previous work run with more idealized collapse scenarios). We explore saturation of amplification of the magnetic field, which could potentially become dynamically important in subsequent, fully-resolved calculations. We have also identified a relatively surprising phenomena that is purely hydrodynamic: the higher-resolved simulations possess substantially different characteristics, including higher infall-velocity, increased temperatures inside 1000 AU, and decreased molecular hydrogen content in the innermost region. Furthermore, we find that disk formation is suppressed in higher-resolution calculations, at least at the times that we can follow the calculation. We discuss the …
Date: February 22, 2012
Creator: Turk, Matthew J.; Oishi, Jeffrey S.; Abel, Tom & Bryan, Greg
System: The UNT Digital Library
Photon Strength and the Low-Energy Enhancement (open access)

Photon Strength and the Low-Energy Enhancement

The ability of atomic nuclei to emit and absorb photons with energy E{sub {gamma}} is known as the photon strength function f(E{sub {gamma}}). It has direct relevance to astrophysical element formation via neutron capture processes due to its central role in nuclear reactions. Studies of f(E{sub {gamma}}) have benefited from a wealth of data collected in neutron capture and direct reactions but also from newly commissioned inelastic photon scattering facilities. The majority of these experimental methods, however, rely on the use of models because measured {gamma}-ray spectra are simultaneously sensitive to both the nuclear level density and f(E{sub {gamma}}). As excitation energy increases towards the particle separation energies, the level density increases rapidly, creating the quasi-continuum. Nuclear properties in this excitation energy region are best characterized using statistical quantities, such as f(E{sub {gamma}}). A point of contention in studies of the quasi-continuum has been an unexpected and unexplained increase in f(E{sub {gamma}}) at low {gamma}-ray energies (i.e. below E{sub {gamma}} {approx}3 MeV) in a subset of light-to-medium mass nuclei. Ideally, a new model-independent experimental technique is required to address questions regarding the existence and origin of this low-energy enhancement in f(E{sub {gamma}}). Here such a model-independent approach is presented for …
Date: February 22, 2012
Creator: Wiedeking, M; Bernstein, L A; Krticka, M; Bleuel, D L; Allmond, J M; Basunia, M S et al.
System: The UNT Digital Library
Reach the Bottom Line of the Sbottom Search (open access)

Reach the Bottom Line of the Sbottom Search

We propose a new search strategy for directly-produced sbottoms at the LHC with a small mass splitting between the sbottom and its decayed stable neutralino. Our search strategy is based on boosting sbottoms through an energetic initial state radiation jet. In the final state, we require a large missing transverse energy and one or two b-jets besides the initial state radiation jet. We also define a few kinematic variables to further increase the discovery reach. For the case that the sbottom mainly decays into the bottom quark and the stable neutralino, we have found that even for a mass splitting as small as 10 GeV sbottoms with masses up to around 400 GeV can be excluded at the 95% confidence level with 20 inverse femtobarn data at the 8 TeV LHC.
Date: May 22, 2012
Creator: Alvarez, Ezequiel & Bai, Yang
System: The UNT Digital Library
X-Band RF Gun Development (open access)

X-Band RF Gun Development

In support of the MEGa-ray program at LLNL and the High Gradient research program at SLAC, a new X-band multi-cell RF gun is being developed. This gun, similar to earlier guns developed at SLAC for Compton X-ray source program, will be a standing wave structure made of 5.5 cells operating in the pi mode with copper cathode. This gun was designed following criteria used to build SLAC X-band high gradient accelerating structures. It is anticipated that this gun will operate with surface electric fields on the cathode of 200 MeV/m with low breakdown rate. RF will be coupled into the structure through a final cell with symmetric duel feeds and with a shape optimized to minimize quadrupole field components. In addition, geometry changes to the original gun, operated with Compton X-ray source, will include a wider RF mode separation, reduced surface electric and magnetic fields.
Date: June 22, 2012
Creator: Vlieks, Arnold; Dolgashev, Valery; Tantawi, Sami; Anderson, Scott; Hartemann, Fred & Marsh, Roark
System: The UNT Digital Library
A Green Prison: The Santa Rita Jail Campus Microgrid (open access)

A Green Prison: The Santa Rita Jail Campus Microgrid

A large microgrid project is nearing completion at Alameda County’s twenty-two-year-old 45 ha 4,000-inmate Santa Rita Jail, about 70 km east of San Francisco. Often described as a green prison, it has a considerable installed base of distributed energy resources (DER) including an eight-year old 1.2 MW PV array, a five-year old 1 MW fuel cell with heat recovery, and considerable efficiency investments. A current US$14 M expansion adds a 2 MW-4 MWh Li-ion battery, a static disconnect switch, and various controls upgrades. During grid blackouts, or when conditions favor it, the Jail can now disconnect from the grid and operate as an island, using the on-site resources described together with its back-up diesel generators. In other words, the Santa Rita Jail is a true microgrid, or μgrid, because it fills both requirements, i.e. it is a locally controlled system, and it can operate both grid connected and islanded. The battery’s electronics includes Consortium for Electric Reliability Technology (CERTS) Microgrid technology. This enables the battery to maintain energy balance using droops without need for a fast control system.
Date: January 22, 2012
Creator: Marnay, Chris; DeForest, Nicholas & Lai, Judy
System: The UNT Digital Library
Components of the dilepton continuum in Pb+Pb collisions at sqrt s = 2.76 TeV (open access)

Components of the dilepton continuum in Pb+Pb collisions at sqrt s = 2.76 TeV

None
Date: February 22, 2012
Creator: Vogt, R; Shukla, P & Kumar, V
System: The UNT Digital Library
Nuclear PDFs (open access)

Nuclear PDFs

N/A
Date: October 22, 2012
Creator: D., De Florian; M., Stratmann; Zurita, P. & Sassot, R.
System: The UNT Digital Library
A REALISTIC EXAMINATION OF COLD FUSION CLAIMS 24 YEARS LATER (open access)

A REALISTIC EXAMINATION OF COLD FUSION CLAIMS 24 YEARS LATER

On March 29, 1989, chemists Martin Fleischmann and Stanley Pons announced they had discovered an effect whose explanation was required to lie in the realm of nuclear reactions. Their claim, and those subsequent to it of roughly similar nature, became known as ‘cold fusion’. Research continues to this day on this effect, but what has become clear is that whatever it is, it is not a conventional fusion process. Thus the ‘cold fusion’ moniker is somewhat inappropriate and many current researchers in the field prefer the term “Low Energy Nuclear Reactions (LENR)”, although other terms have been coined for it as well. the results developed out of the LENR research do in fact show something is happening to produce signals which might be interpreted as supporting nuclear reactions (which is what encourages and sustains LENR researchers), but which can also be interpreted via a set of unique and interesting conventional processes. The focus of this document is to describe and address recent objections to such processes so that subsequent LENR research can be guided to develop information that will determine whether either set of explanations has merit. It is hoped that criteria delineated herein will aid the USDOE and other …
Date: October 22, 2012
Creator: Shanahan, K.
System: The UNT Digital Library