LaserFest Celebration (open access)

LaserFest Celebration

LaserFest was the yearlong celebration, during 2010, of the 50th anniversary of the demonstration of the first working laser. The goals of LaserFest were: to highlight the impact of the laser in its manifold commercial, industrial and medical applications, and as a tool for ongoing scientific research; to use the laser as one example that illustrates, more generally, the route from scientific innovation to technological application; to use the laser as a vehicle for outreach, to stimulate interest among students and the public in aspects of physical science; to recognize and honor the pioneers who developed the laser and its many applications; to increase awareness among policymakers of the importance of R&D funding as evidenced by such technology as lasers. One way in which LaserFest sought to meet its goals was to encourage relevant activities at a local level all across the country -- and also abroad -- that would be identified with the larger purposes of the celebration and would carry the LaserFest name. Organizers were encouraged to record and advertise these events through a continually updated web-based calendar. Four projects were explicitly detailed in the proposals: 1) LaserFest on the Road; 2) Videos; 3) Educational material; and 4) …
Date: August 25, 2011
Creator: Chodos, Alan & Rogan, Elizabeth A.
Object Type: Text
System: The UNT Digital Library
Costilla County Biodiesel Pilot Project (open access)

Costilla County Biodiesel Pilot Project

The Costilla County Biodiesel Pilot Project has demonstrated the compatibility of biodiesel technology and economics on a local scale. The project has been committed to making homegrown biodiesel a viable form of community economic development. The project has benefited by reducing risks by building the facility gradually and avoiding large initial outlays of money for facilities and technologies. A primary advantage of this type of community-scale biodiesel production is that it allows for a relatively independent, local solution to fuel production. Successfully using locally sourced feedstocks and putting the fuel into local use emphasizes the feasibility of different business models under the biodiesel tent and that there is more than just a one size fits all template for successful biodiesel production.
Date: August 25, 2011
Creator: Doon, Ben & Quintana, Dan
Object Type: Report
System: The UNT Digital Library
Elementary Particle Physics at Baylor (Final Report) (open access)

Elementary Particle Physics at Baylor (Final Report)

This report summarizes the activities of the Baylor University Experimental High Energy Physics (HEP) group on the Collider Detector at Fermilab (CDF) experiment from August 15, 2005 to May 31, 2012. Led by the Principal Investigator (Dr. Jay R. Dittmann), the Baylor HEP group has actively pursued a variety of cutting-edge measurements from proton-antiproton collisions at the energy frontier.
Date: August 25, 2012
Creator: Dittmann, J.R.
Object Type: Report
System: The UNT Digital Library
RESULTS FOR THE SECOND QUARTER 2011 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS (open access)

RESULTS FOR THE SECOND QUARTER 2011 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS

The Saltstone Facility is designed and permitted to immobilize and dispose of low-level radioactive and hazardous liquid waste (salt solution) remaining from the processing of radioactive material at the Savannah River Site. Low-level waste (LLW) streams from the Effluent Treatment Project (ETP), H-Canyon, the DDA (Deliquification, Dissolution, and Adjustment) process, and the decontaminated salt solution product from the Actinide Removal Process/Modular Caustic Side Solvent Extraction (CSSX) Unit (ARP/MCU) process are stored in Tank 50 until the LLW can be transferred to the Saltstone Facility for treatment and disposal. The LLW must meet the specified waste acceptance criteria (WAC) before it is processed into saltstone. The specific chemical and radionuclide contaminants and their respective WAC limits are listed in the current Saltstone WAC. Waste Solidification Engineering (WSE) requested that Savannah River National Laboratory (SRNL) perform quarterly analysis on saltstone samples. The concentrations of chemical and radionuclide contaminants are measured to ensure the saltstone produced during each quarter is in compliance with the current WAC. This report documents the concentrations of chemical and radionuclide contaminants for the 2011 Second Quarter samples collected from Tank 50 on April 4, 2011 and discusses those results in further detail than the previously issued results report. …
Date: August 25, 2011
Creator: Eibling, R.
Object Type: Report
System: The UNT Digital Library
New Manufacturing Method for Paper Filler and Fiber Material (open access)

New Manufacturing Method for Paper Filler and Fiber Material

The use of fillers in printing and writing papers has become a prerequisite for competing in a global market to reduce the cost of materials. Use of calcium carbonates (ranging from 18% to 30%) as filler is a common practice in the paper industry but the choices of fillers for each type of papers vary widely according to its use. The market for uncoated digital printing paper is one that continues to introduce exciting growth projections. and it is important to understand the effect that new manufacturing methods of calcium carbonates have on the energy efficiency and paper production. Research conducted under this award showed that the new fiber filler composite material has the potential to increase the paper filler content by up to 5% without losing mechanical properties. Benefits of the technology can be summarized as follows for a 1% filler increase per metric ton of paper produced: (i) production cost savings over $12, (ii) Energy savings of 100,900 btu, (iii) CO{sub 2} emission savings of 33 lbs, and additional savings for wood preparation, pulping, recovery of 203593 btu with a 46lbs of CO{sub 2} emission savings per 1% filler increase. In addition the technology has the potential to …
Date: August 25, 2013
Creator: Doelle, Klaus
Object Type: Report
System: The UNT Digital Library
Case Study of the Failure of two 13.8kV Control & Metering Transformers that caused significant Equipment Damage (open access)

Case Study of the Failure of two 13.8kV Control & Metering Transformers that caused significant Equipment Damage

The degradation and failure of cast-coil epoxy windings within 13.8kV control power transformers and metering potential transformers has been shown to be dangerous to both equipment and personnel, even though best industrial design practices were followed. Accident scenes will be examined for two events at a U.S. Department of Energy laboratory. Failure modes will be explained and current design practices discussed with changes suggested to prevent a recurrence and to minimize future risk. New maintenance philosophies utilizing partial discharge testing of the transformers as a prediction of end-of-life will be examined.
Date: August 25, 2011
Creator: Dreifuerst, G R; Chew, D B; Mangonon, H L & Swyers, P W
Object Type: Article
System: The UNT Digital Library
Modeling of a Slanted-Hole Collimator in a Compact Endocavity Gamma Camera (open access)

Modeling of a Slanted-Hole Collimator in a Compact Endocavity Gamma Camera

N/A
Date: August 25, 2013
Creator: Cui, Y.; Karmuda, M.; Lall, T.; Ionson, J.; Camarda, G.; Hossain, A. et al.
Object Type: Article
System: The UNT Digital Library
Estimation of Equivalent Sea Level Cosmic Ray Exposure for Low Background Experiment (open access)

Estimation of Equivalent Sea Level Cosmic Ray Exposure for Low Background Experiment

While scientists at CERN and other particle accelerators around the world explore the boundaries of high energy physics, the Majorana project investigates the other end of the spectrum with its extremely sensitive, low background, low energy detector. The MAJORANA DEMONSTRATOR aims to detect neutrinoless double beta decay (0νββ), a rare theoretical process in which two neutrons decay into two protons and two electrons, without the emission of the two antineutrinos that are a product of a normal double beta decay. This process is only possible if – and therefore a detection would prove — the neutrino is a Majorana particle, meaning that it is its own antiparticle [Aaselth et al. 2004] . The existence of such a decay would also disprove lepton conservation and give information about the neutrino's mass.
Date: August 25, 2012
Creator: Greene, Austen T. & Orrell, John L.
Object Type: Report
System: The UNT Digital Library
Properties and Interactions of Elementary Particles (open access)

Properties and Interactions of Elementary Particles

We summarize the accomplishments over the last renewal period in a broad program of research in experimental and theoretical High Energy Physics, conducted at the University of Michigan, and supported by the U.S. Department of Energy.
Date: August 25, 2012
Creator: Amidei, Dante; Campbell, Myron; Huterer, Dragan; Kane, Gordon; Liu, James; Qian, Jianming et al.
Object Type: Report
System: The UNT Digital Library
Construction of a Novel Tabletop X-Ray Generator (open access)

Construction of a Novel Tabletop X-Ray Generator

None
Date: August 25, 2010
Creator: Hostetter, James & /SLAC, /Louisiana State U.
Object Type: Report
System: The UNT Digital Library
Post-growth Annealing of CdZnTe crystals: an analysis of defect-structures and opto-electronic properties (open access)

Post-growth Annealing of CdZnTe crystals: an analysis of defect-structures and opto-electronic properties

N/A
Date: August 25, 2013
Creator: Yang, G.; Bolotnikov, A. E.; Fochuk, P. M.; Camarda, G. S.; Hossain, A.; Roy, U. et al.
Object Type: Article
System: The UNT Digital Library
TECHNETIUM SORPTION MEDIA REVIEW (open access)

TECHNETIUM SORPTION MEDIA REVIEW

This report presents information and references to aid in the selection of 99Tc sorption media for feasibility studies regarding the removal of 99Tc from Hanford's low activity waste. The report contains literature search material for sorption media (including ion exchange media) for the most tested media to date, including SuperLig 639, Reillex HPQ, TAM (Kruion), Purolite A520E and A530E, and Dowex 1X8. The U.S. Department of Energy (DOE), Office of River Protection (ORP) is responsible for management and completion of the River Protection Project (RPP) mission, which comprises both the Hanford Site tank farms and the Waste Treatment and Immobilization Plant (WTP). The RPP mission is to store, retrieve and treat Hanford's tank waste; store and dispose of treated wastes; and close the tank farm waste management areas and treatment facilities in a safe, environmentally compliant, cost-effective and energy-effective manner.
Date: August 25, 2011
Creator: JB, DUNCAN; SE, KELLY; RA, ROBBINS; RD, ADAMS; MA, THORSON & CC, HAASS
Object Type: Report
System: The UNT Digital Library
Measurements of Form Factors with the BaBar Experiment (open access)

Measurements of Form Factors with the BaBar Experiment

Selected recent results on measurements of form factors by the BaBar Collaboration are reviewed, including e{sup +}e{sup -} {yields} {eta}{prime}{gamma}, leptonic and semileptonic charm decays from data collected at or near the {Upsilon}(4S) resonance.
Date: August 25, 2011
Creator: Li, Selina Z.
Object Type: Article
System: The UNT Digital Library
Ground Movement in SSRL Ring (open access)

Ground Movement in SSRL Ring

Users of the Stanford Synchrotron Radiation Lightsource (SSRL) are being affected by diurnal motion of the synchrotron's storage ring, which undergoes structural changes due to outdoor temperature fluctuations. In order to minimize the effects of diurnal temperature fluctuations, especially on the vertical motion of the ring floor, scientists at SSRL tried three approaches: painting the storage ring white, covering the asphalt in the middle of the ring with highly reflective Mylar and installing Mylar on a portion of the ring roof and walls. Vertical motion in the storage ring is measured by a Hydrostatic Leveling System (HLS), which calculates the relative height of water in a pipe that extends around the ring. The 24-hr amplitude of the floor motion was determined using spectral analysis of HLS data, and the ratio of this amplitude before and after each experiment was used to quantitatively determine the efficacy of each approach. The results of this analysis showed that the Mylar did not have any significant effect on floor motion, although the whitewash project did yield a reduction in overall HLS variation of 15 percent. However, further analysis showed that the reduction can largely be attributed to a few local changes rather than an …
Date: August 25, 2011
Creator: Sunikumar, Nikita & /SLAC, /UCLA
Object Type: Report
System: The UNT Digital Library
Accelerator Production Options for 99MO (open access)

Accelerator Production Options for 99MO

Shortages of {sup 99}Mo, the most commonly used diagnostic medical isotope, have caused great concern and have prompted numerous suggestions for alternate production methods. A wide variety of accelerator-based approaches have been suggested. In this paper we survey and compare the various accelerator-based approaches.
Date: August 25, 2010
Creator: Bertsche, Kirk
Object Type: Article
System: The UNT Digital Library
The added economic and environmental value of plug-in electric vehicles connected to commercial building microgrids (open access)

The added economic and environmental value of plug-in electric vehicles connected to commercial building microgrids

Connection of electric storage technologies to smartgrids or microgrids will have substantial implications for building energy systems. In addition to potentially supplying ancillary services directly to the traditional centralized grid (or macrogrid), local storage will enable demand response. As an economically attractive option, mobile storage devices such as plug-in electric vehicles (EVs) are in direct competition with conventional stationary sources and storage at the building. In general, it is assumed that they can improve the financial as well as environmental attractiveness of renewable and fossil based on-site generation (e.g. PV, fuel cells, or microturbines operating with or without combined heat and power). Also, mobile storage can directly contribute to tariff driven demand response in commercial buildings. In order to examine the impact of mobile storage on building energy costs and carbon dioxide (CO2) emissions, a microgrid/distributed-energy-resources (DER) adoption problem is formulated as a mixed-integer linear program with minimization of annual building energy costs applying CO2 taxes/CO2 pricing schemes. The problem is solved for a representative office building in the San Francisco Bay Area in 2020. By using employees' EVs for energy management, the office building can arbitrage its costs. But since the car battery lifetime is reduced, a business model …
Date: August 25, 2010
Creator: Stadler, Michael; Momber, Ilan; Megel, Olivier; Gomez, Tomás; Marnay, Chris; Beer, Sebastian et al.
Object Type: Article
System: The UNT Digital Library
Fiber Accelerating Structures (open access)

Fiber Accelerating Structures

One of the options for future particle accelerators are photonic band gap (PBG) fiber accelerators. PBG fibers are specially designed optical fibers that use lasers to excite an electric field that is used to accelerate electrons. To improve PBG accelerators, the basic parameters of the fiber were tested to maximize defect size and acceleration. Using the program CUDOS, several accelerating modes were found that maximized these parameters for several wavelengths. The design of multiple defects, similar to having closely bound fibers, was studied to find possible coupling or the change of modes. The amount of coupling was found to be dependent on distance separated. For certain distances accelerating coupled modes were found and examined. In addition, several non-periodic fiber structures were examined using CUDOS. The non-periodic fibers produced several interesting results and promised more modes given time to study them in more detail.
Date: August 25, 2010
Creator: Hammond, Andrew P. & /SLAC, /Reed Coll.
Object Type: Report
System: The UNT Digital Library
Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation (open access)

Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation

Massive stars influence their surroundings through radiation, winds, and supernova explosions far out of proportion to their small numbers. However, the physical processes that initiate and govern the birth of massive stars remain poorly understood. Two widely discussed models are monolithic collapse of molecular cloud cores and competitive accretion. To learn more about massive star formation, we perform simulations of the collapse of rotating, massive, cloud cores including radiative heating by both non-ionizing and ionizing radiation using the FLASH adaptive mesh refinement code. These simulations show fragmentation from gravitational instability in the enormously dense accretion flows required to build up massive stars. Secondary stars form rapidly in these flows and accrete mass that would have otherwise been consumed by the massive star in the center, in a process that we term fragmentation-induced starvation. This explains why massive stars are usually found as members of high-order stellar systems that themselves belong to large clusters containing stars of all masses. The radiative heating does not prevent fragmentation, but does lead to a higher Jeans mass, resulting in fewer and more massive stars than would form without the heating. This mechanism reproduces the observed relation between the total stellar mass in the cluster …
Date: August 25, 2010
Creator: Peters, Thomas; /ZAH, Heidelberg; Klessen, Ralf S.; /ZAH, Heidelberg /KIPAC, Menlo Park; Mac Low, Mordecai-Mark; Hist., /Amer. Museum Natural et al.
Object Type: Article
System: The UNT Digital Library
Coherence Properties of the LCLS (open access)

Coherence Properties of the LCLS

The LINAC Coherent Light Source (LCLS), an X-Ray free-electron laser(FEL) based on the self amplified spontaneous emission principle, has recently come on-line. For many users it is desirable to have an idea of the level of transverse coherence of the X-Ray beam produced. In this paper, we analyze the output of GENESIS simulations of electrons traveling through the FEL. We first test the validity of an approach that ignores the details of how the beam was produced, and instead, by assuming a Gaussian-Schell model of transverse coherence, predicts the level of transverse coherence simply through looking at the beam radius at several longitudinal slices. We then develop a Markov chain Monte Carlo approach to calculating the degree of transverse coherence, which offers a {approx}100-fold speedup compared to the brute-force algorithm previously in use. We find the beam highly coherent. Using a similar Markov chain Monte Carlo approach, we estimate the reasonability of assuming the beam to have a Gaussian-Schell model of transverse coherence, with inconclusive results.
Date: August 25, 2010
Creator: Ocko, Samuel
Object Type: Report
System: The UNT Digital Library
Vector Boson Jets with BlackHat and Sherpa (open access)

Vector Boson Jets with BlackHat and Sherpa

We review recent NLO QCD results for W, Z + 3-jet production at hadron colliders, computing using BlackHat and SHERPA, and including also some new results for Z + 3-jet production for the LHC at 7 TeV. We report new progress towards the NLO cross section for W + 4-jet production. In particular, we show that the virtual matrix elements produced by BlackHat are numerically stable. We also show that with an improved integrator and tree-level matrix elements from BlackHat, SHERPA produces well-behaved real-emission contributions. As an illustration, we present the real-emission contributions - including dipole-subtraction terms - to the p{sub T} distribution of the fourth jet, for a single subprocess with the maximum number of gluons.
Date: August 25, 2010
Creator: Berger, C.F.; /MIT, LNS; Bern, Z.; /UCLA; Dixon, Lance J.; /SLAC et al.
Object Type: Article
System: The UNT Digital Library
Optimization of the LCLS Single Pulse Shutter (open access)

Optimization of the LCLS Single Pulse Shutter

A mechanical shutter which operates on demand is used to isolate a single pulse from a 120 Hz X-ray source. This is accomplished with a mechanical shutter which is triggered on demand with frequencies ranging from 0 to 10 Hz. The single pulse shutter is an iron blade that oscillates on a pivot in response to a force generated by a pair of pulsed electromagnets (current driven teeter-totter). To isolate an individual pulse from the X-ray beam, the motion of the mechanical shutter should be synchronized in such a way that it allows a single pulse to pass through the aperture and blocks the other incoming pulses. Two consecutive pulses are only {approx} 8 ms apart and the shutter is required to complete one full cycle such that no two pulses pass through the opening. Also the opening of the shutter blade needs to be at least 4 mm so that a 1 mm diameter rms Gaussian beam can pass through without modulation. However, the 4 mm opening is difficult to obtain due to blade rebound and oscillation of the blade after colliding with the electromagnet. The purpose of this project is to minimize and/or totally eliminate the rebound of …
Date: August 25, 2010
Creator: Adera, Solomon & /Georgia Tech., Atlanta /SLAC
Object Type: Report
System: The UNT Digital Library
First Demonstration of the Echo-Enabled Harmonic Generation Technique for Short-Wavelength Seeded Free Electron Lasers (open access)

First Demonstration of the Echo-Enabled Harmonic Generation Technique for Short-Wavelength Seeded Free Electron Lasers

We report the first experimental demonstration of the echo-enabled harmonic generation (EEHG) technique which holds great promise for generation of high power, fully coherent short-wavelength radiation. In this experiment, coherent radiation at the 3rd and 4th harmonic of the second seed laser is generated from the so-called beam echo effect. The experiment confirms the physics behind this technique and paves the way for applying the EEHG technique for seeded x-ray free electron lasers.
Date: August 25, 2010
Creator: Xiang, D.; Colby, E.; Dunning, M.; Gilevich, S.; Hast, C.; Jobe, K. et al.
Object Type: Article
System: The UNT Digital Library
Essence of the Vacuum Quark Condensate (open access)

Essence of the Vacuum Quark Condensate

We show that the chiral-limit vacuum quark condensate is qualitatively equivalent to the pseudoscalar meson leptonic decay constant in the sense that they are both obtained as the chiral-limit value of well-defined gauge-invariant hadron-to-vacuum transition amplitudes that possess a spectral representation in terms of the current-quark mass. Thus, whereas it might sometimes be convenient to imagine otherwise, neither is essentially a constant mass-scale that fills all spacetime. This means, in particular, that the quark condensate can be understood as a property of hadrons themselves, which is expressed, for example, in their Bethe-Salpeter or light-front wavefunctions.
Date: August 25, 2010
Creator: Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; Roberts, Craig D.; /Argonne, PHY /Peking U.; Shrock, Robert; /YITP, Stony Brook et al.
Object Type: Article
System: The UNT Digital Library
Dynamic Star Formation in the Massive DR21 Filament (open access)

Dynamic Star Formation in the Massive DR21 Filament

The formation of massive stars is a highly complex process in which it is unclear whether the star-forming gas is in global gravitational collapse or an equilibrium state supported by turbulence and/or magnetic fields. By studying one of the most massive and dense star-forming regions in the Galaxy at a distance of less than 3 kpc, i.e. the filament containing the well-known sources DR21 and DR21(OH), we attempt to obtain observational evidence to help us to discriminate between these two views. We use molecular line data from our {sup 13}CO 1 {yields} 0, CS 2 {yields} 1, and N{sub 2}H{sup +} 1 {yields} 0 survey of the Cygnus X region obtained with the FCRAO and CO, CS, HCO{sup +}, N{sub 2}H{sup +}, and H{sub 2}CO data obtained with the IRAM 30m telescope. We observe a complex velocity field and velocity dispersion in the DR21 filament in which regions of the highest column-density, i.e., dense cores, have a lower velocity dispersion than the surrounding gas and velocity gradients that are not (only) due to rotation. Infall signatures in optically thick line profiles of HCO{sup +} and {sup 12}CO are observed along and across the whole DR21 filament. By modelling the observed …
Date: August 25, 2010
Creator: Schneider, N.; Csengeri, T.; Bontemps, S.; Motte, F.; Simon, R.; Hennebelle, P. et al.
Object Type: Article
System: The UNT Digital Library