States

Molecular Markers of Lung Cancer in MAYAK Workers (open access)

Molecular Markers of Lung Cancer in MAYAK Workers

The molecular mechanisms that result in the elevated risk for lung cancer associated with exposure to radiation have not been well characterized. Workers from the MAYAK nuclear enterprise are an ideal cohort in which to study the molecular epidemiology of cancer associated with radiation exposure and to identify the genes targeted for inactivation that in turn affect individual risk for radiation-induced lung cancer. Epidemiology studies of the MAYAK cohort indicate a significantly higher frequency for adenocarcinoma and squamous cell carcinoma (SCC) in workers than in a control population and a strong correlation between these tumor types and plutonium exposure. Two hypotheses will be evaluated through the proposed studies. First, radiation exposure targets specific genes for inactivation by promoter methylation. This hypothesis is supported by our recent studies with the MAYAK population that demonstrated the targeting of the p16 gene for inactivation by promoter methylation in adenocarcinomas from workers (1). Second, genes inactivated in tumors can serve as biomarkers for lung cancer risk in a cancer-free population of workers exposed to plutonium. Support for this hypothesis is based on exciting preliminary results of our nested, case-control study of persons from the Colorado cohort. In that study, a panel of methylation markers …
Date: February 15, 2007
Creator: Belinsky, Steven A.
Object Type: Report
System: The UNT Digital Library
Final Technical Report - "Determining How Magnetic Helicity Injection Really Works" (open access)

Final Technical Report - "Determining How Magnetic Helicity Injection Really Works"

This research program involved direct observation of the complicated plasma dynamics underlying spheromak formation. Spheromaks are self-organizing magnetically dominated plasma configurations which potentially offer a simple, low-cost means for confining the plasma in a controlled thermonuclear fusion reactor. The spheromak source used in these studies was a coaxial co-planar magnetized plasma gun which was specifically designed to have the simplest relevant geometry. The simplicity of the geometry facilitated understanding of the basic physics and minimized confusion that would otherwise have resulted from complexities due to the experimental geometry. The coaxial plasma gun was mounted on one end of a large vacuum tank that had excellent optical access so the spheromak formation process could be tracked in detail using ultra-high speed cameras. The main accomplishments of this research program were (1) obtaining experimental data characterizing the detailed physics underlying spheromak formation and the development of new theoretical models motivated by these observations, (2) determining the relationship between spheromak physics and astrophysical jets, (3) developing a new high-speed camera diagnostic for the SSPX spheromak at the Lawrence Livermore National Lab, and (4) training graduate students and postdoctoral fellows.
Date: February 15, 2005
Creator: Bellan, Paul M.
Object Type: Report
System: The UNT Digital Library
Space searches with a quantum robot (open access)

Space searches with a quantum robot

Quantum robots are described as mobile quantum computers and ancillary systems that move in and interact with arbitrary environments. Their dynamics is given as tasks which consist of sequences of alternating computation and action phases. A task example is considered in which a quantum robot searches a space region to find the location of a system. The possibility that the search can be more efficient than a classical search is examined by considering use of Grover's Algorithm to process the search results. This is problematic for two reasons. One is the removal of entanglements generated by the (reversible) search process. The other is that (ignoring the entanglement problem), the search process in 2 dimensional space regions is no more efficient than a classical search. However quantum searches of higher dimensional space regions are more efficient than classical searches. Reasons why quantum robots are interesting independent of these results are briefly summarized.
Date: February 15, 2000
Creator: Benioff, P.
Object Type: Article
System: The UNT Digital Library
NLO Jet Physics with BlackHat (open access)

NLO Jet Physics with BlackHat

We present several results obtained using the BLACKHAT next-to-leading order QCD program library, in conjunction with SHERPA. In particular, we present distributions for vector boson plus 1,2,3-jet production at the Tevatron and at the asymptotic running energy of the Large Hadron Collider, including new Z + 3-jet distributions. The Z + 2-jet predictions for the second-jet P{sub T} distribution are compared to CDF data. We present the jet-emission probability at NLO in W + 2-jet events at the LHC, where the tagging jets are taken to be the ones furthest apart in pseudorapidity. We analyze further the large left-handed W{sup {+-}} polarization, identified in our previous study, for W bosons produced at high P{sub T} at the LHC.
Date: February 15, 2010
Creator: Berger, C. F.; Bern, Z.; Dixon, L. J.; Cordero, F. Febres; Forde, D.; Gleisberg, T. et al.
Object Type: Article
System: The UNT Digital Library
TEMPERATURE DISTRIBUTION AND THERMAL STRESS IN REACTOR CORE APPR-1 (open access)

TEMPERATURE DISTRIBUTION AND THERMAL STRESS IN REACTOR CORE APPR-1

The feasibility of the Liquid Metal Fuel Reactor (LMFR) proposed by Brookhaven National Laboratory as a source of electric power was thoroughly investigated. The reference design is based on an LMFR using U dissolved in Bi as the fuel and a thorium bismuthide in Bi slurry as the blanket. Detailed estimates of power costs are presented for electrical power stations from 226 to 904 Mw net electrical capability. (C.W.H.)
Date: February 15, 1956
Creator: Berggren, W. P. & Kroeger, H. R.
Object Type: Report
System: The UNT Digital Library
Geophysical survey for proposed borehole 199-K-108A, 100-K Area (open access)

Geophysical survey for proposed borehole 199-K-108A, 100-K Area

The objective of the electromagnetic survey was to locate subsurface obstructions that may affect the drilling of proposed borehole, 199-K-108A, about 75 ft southeast of the 105 KW Building, 100-K Area. Based upon the results of the survey, possible drill sites within the zone, with the least likelihood of encountering identified obstructions, were identified.
Date: February 15, 1994
Creator: Bergstrom, K. A. & Mitchell, T. H.
Object Type: Report
System: The UNT Digital Library
Simplifying Multi-loop Integrands of Gauge Theory and Gravity Amplitudes (open access)

Simplifying Multi-loop Integrands of Gauge Theory and Gravity Amplitudes

We use the duality between color and kinematics to simplify the construction of the complete four-loop four-point amplitude of N = 4 super-Yang-Mills theory, including the nonplanar contributions. The duality completely determines the amplitude's integrand in terms of just two planar graphs. The existence of a manifestly dual gauge-theory amplitude trivializes the construction of the corresponding N = 8 supergravity integrand, whose graph numerators are double copies (squares) of the N = 4 super-Yang-Mills numerators. The success of this procedure provides further nontrivial evidence that the duality and double-copy properties hold at loop level. The new form of the four-loop four-point supergravity amplitude makes manifest the same ultraviolet power counting as the corresponding N = 4 super-Yang-Mills amplitude. We determine the amplitude's ultraviolet pole in the critical dimension of D = 11/2, the same dimension as for N = 4 super-Yang-Mills theory. Strikingly, exactly the same combination of vacuum integrals (after simplification) describes the ultraviolet divergence of N = 8 supergravity as the subleading-in-1/N{sub c}{sup 2} single-trace divergence in N = 4 super-Yang-Mills theory.
Date: February 15, 2012
Creator: Bern, Z.; Carrasco, J.J.M.; Dixon, L.J.; Johansson, H. & Roiban, R.
Object Type: Article
System: The UNT Digital Library
NLO Vector Boson Production With Light Jets (open access)

NLO Vector Boson Production With Light Jets

In this contribution we present recent progress in the computation of next-to-leading order (NLO) QCD corrections for the production of an electroweak vector boson in association with jets at hadron colliders. We focus on results obtained using the virtual matrix element library BlackHat in conjunction with SHERPA, focusing on results relevant to understanding the background to top production. The production of a vector boson in association with several jets at the Large Hadron Collider (LHC) is an important background for other Standard Model processes as well as new physics signals. In particular, the production of a W boson in association with many jets is an important background for processes involving one or more top quarks. Precise predictions for the backgrounds are crucial to measurement of top-quark processes. Vector boson production in association with multiple jets is also a very important background for many SUSY searches, as it mimics the signatures of many typical decay chains. Here we will discuss how polarization information can be used as an additional handle to differentiate top pair production from 'prompt' W-boson production. More generally, ratios of observables, for example for events containing a W boson versus those containing a Z boson, are expected to …
Date: February 15, 2012
Creator: Bern, Z.; Diana, G.; Dixon, L.J.; Febres Cordero, F.; Forde, D.; Gleisberg, T. et al.
Object Type: Article
System: The UNT Digital Library
Bounds and self-consistent estimates for elastic constants of polycrystals of hcp solid He{sup 4} (open access)

Bounds and self-consistent estimates for elastic constants of polycrystals of hcp solid He{sup 4}

Recent advances in methods for computing both Hashin-Shtrikman bounds and related selfconsistent (or CPA) estimates of elastic constants for polycrystals composed of randomly oriented crystals can be applied successfully to hexagonal close packed solid He{sup 4}. In particular, since the shear modulus C{sub 44} of hexagonal close-packed solid He is known to undergo large temperature variations when 20 mK {<=}#20; T {<=}#20; 200 mK, bounds and estimates computed with this class of effective medium methods, while using C{sub 44} {r_arrow} 0 as a proxy for melting, are found to be both qualitatively and quantitatively very similar to prior results obtained using Monte Carlo methods. Hashin- Shtrikman bounds provide significantly tighter constraints on the polycrystal behavior than do the traditional Voigt and Reuss bounds.
Date: February 15, 2012
Creator: Berryman, J. G.
Object Type: Article
System: The UNT Digital Library
REPETITIVELY PULSED ACCELERATOR BOOSTERS (open access)

REPETITIVELY PULSED ACCELERATOR BOOSTERS

None
Date: February 15, 1965
Creator: Beyster, J.R. & Russell, J.L.
Object Type: Report
System: The UNT Digital Library
Design Issues for the ILC Positron Source (open access)

Design Issues for the ILC Positron Source

A positron source for the International Linear Collider (ILC) can be designed using either a multi-GeV electron beam or a multi-MeV photon beam impinging on a metal target. The major design issues are: choice of drive beam and its generation, choice of target material, the target station, positron capture section, target vault and beam transport to the ILC positron damping ring complex. This paper lists the ILC positron source requirements and their implications for the design of the positron source. A conceptual design for the ILC is expected to be finished in the next two years. With emphasis on this timescale, source design issues and possible solutions are discussed.
Date: February 15, 2006
Creator: Bharadwaj, V.; Batygin, Yu. K.; Pitthan, R.; Schultz, D. C.; Sheppard, J.; Vincke, H. et al.
Object Type: Article
System: The UNT Digital Library
Conceptual design for the STAR barrel electromagnetic calorimeter support rings (open access)

Conceptual design for the STAR barrel electromagnetic calorimeter support rings

The STAR electromagnetic calorimeter (EMC) will be used to measure the energy of photons and electrons from collisions of beams of particles in the RHIC accelerator under construction at Brookhaven National Laboratory. The present design is documented in the EMC Conceptual Design Report, and consists of a cylindrical barrel and two flat endcap calorimeter sections. The barrel EMC will consist of 120 modules, each subtending 6{degrees} in azimuthal angle about the beam ({phi}), and half the barrel length. Each module will be subdivided into ``towers`` of alternating scintillator and lead, which project to the nominal interaction point. There is a strong coupling between the designs for the EMC and for the conventional solenoidal magnet, which will be located immediately outside the barrel EMC. For example, the inner radius of the magnet must be minimized to lower costs and to reduce the STAR detector`s outer diameter to fit within constraints of the existing detector building. This condition requires the calorimeter modules to be just thick enough to accomplish physics goals and to support their weight with small deflections. This note describes progress in the design of the EMC support rings. Several ring designs and methods of construction have been considered. In …
Date: February 15, 1994
Creator: Bielick, E.; Fornek, T.; Spinka, H. & Underwood, D.
Object Type: Report
System: The UNT Digital Library
Evaluation of selected chemical processes for production of low-cost silicon (Phase III). Silicon Material Task, Low-Cost Solar Array Project. Thirteenth quarterly progress report, October 1-December 31, 1978 (open access)

Evaluation of selected chemical processes for production of low-cost silicon (Phase III). Silicon Material Task, Low-Cost Solar Array Project. Thirteenth quarterly progress report, October 1-December 31, 1978

Refinements of the design of the 50 MT/year Experimental Process System Development Unit (EPSDU) have been made and competitive bids have been received from mechanical, electrical, and structural contractors. Emergency procedures have been defined to counter a variety of contingencies disclosed in operations and safety reviews. Work continues with the fluidized-bed model to define conditions under which useful segregation of large particles can be obtained. Experimental work with an electrolytic cell for zinc chloride disclosed no significant increase in power efficiency by steps taken to increase electrolyte circulation. On the basis of materials compatibility and permeability tests, 310 stainless steel was chosen for the shell of the fluidized-bed reactor and SiC-coated graphite for the liner. Experiments on the volatility of lead, iron, and cadmium at the ppM level in zinc at its boiling point are being continued with provisions being made to withdraw molten samples so as to avoid segregation on freezing, believed to be the cause of earlier discrepancies.
Date: February 15, 1979
Creator: Blocher, J.M. Jr. & Browning, M.F.
Object Type: Report
System: The UNT Digital Library
Preliminary evaluation of 30 potential granitic rock sites for a radioactive waste storage facility in southern Nevada (open access)

Preliminary evaluation of 30 potential granitic rock sites for a radioactive waste storage facility in southern Nevada

Results of preliminary study are presented which was performed under subtask 2.7 of the NTS Terminal Waste Storage Program Plan for 1978. Subtask 2.7 examines the feasibility of locating a nuclear waste repository in a granitic stock or pluton in southern Nevada near the Nevada Test Site (NTS). It is assumed for the purposes of this study that such a repository cannot be located at NTS. This assumption may or may not be correct. This preliminary report does not identify a particular site as being a suitable location for a repository. Nor does it absolutely eliminate a particular site from further consideration. It does, however, answer the basic question of probable suitability of some of the sites and present a systematic method for site evaluation. Since the findings of this initial study have been favorable, it will be followed by more exhaustive and detailed studies of the original 30 sites and perhaps others. In future studies some of the evaluation criteria used in the preliminary study may be modified or eliminated, and new criteria may be introduced.
Date: February 15, 1978
Creator: Boardman, C.R. & Knutson, C.F.
Object Type: Report
System: The UNT Digital Library
Advanced, Graphite-Matrix, Dispersion-Type Fuel Systems And Research on Graphite. Quarterly Progress Report for the Period Ending February 14, 1965 (open access)

Advanced, Graphite-Matrix, Dispersion-Type Fuel Systems And Research on Graphite. Quarterly Progress Report for the Period Ending February 14, 1965

None
Date: February 15, 1965
Creator: Bokros, J. C.; Goeddel, W. V.; Lonsdale, H. K.; Price, R. J.; White, J. L. & Zumwalt, L. R.
Object Type: Report
System: The UNT Digital Library
Modeling Antimortar Lethality by a Solid-State Heat-Capacity Laser (open access)

Modeling Antimortar Lethality by a Solid-State Heat-Capacity Laser

We have studied the use of a solid-state heat-capacity laser (SSHCL) in mortar defense. This type of laser, as built at LLNL, produces high-energy pulses with a wavelength of about 1 {micro}m and a pulse repetition rate of 200 Hz. Currently, the average power is about 26 kW. Our model of target interactions includes optical absorption, two-dimensional heat transport in the metal casing and explosive, melting, wind effects (cooling and melt removal), high-explosive reactions, and mortar rotation. The simulations continue until HE initiation is reached. We first calculate the initiation time for a range of powers on target and spot sizes. Then we consider an engagement geometry in which a mortar is fired at an asset defended by a 100-kW SSHCL. Propagation effects such as diffraction, turbulent broadening, scattering, and absorption are calculated for points on the trajectory, by means of a validated model. We obtain kill times and fluences, as functions of the rotation rate. These appear quite feasible.
Date: February 15, 2005
Creator: Boley, C D & Rubenchik, A M
Object Type: Article
System: The UNT Digital Library
Third-Party Finance for Commercial Photovoltaic Systems: The Rise of the PPA (open access)

Third-Party Finance for Commercial Photovoltaic Systems: The Rise of the PPA

Installations of grid-connected photovoltaic (PV) systems in the United States have increased dramatically in recent years, growing from less than 20 MW in 2000 to nearly 500 MW at the end of 2007, a compound average annual growth rate of 59%. Of particular note is the increasing contribution of 'non-residential' grid-connected PV systems--defined here as those systems installed on the customer (rather than utility) side of the meter at commercial, institutional, non-profit, or governmental properties--to the overall growth trend. Although there is some uncertainty in the numbers, non-residential PV capacity grew from less than half of aggregate annual capacity installations in 2000-2002 to nearly two-thirds in 2007. This relative growth trend is expected to have continued through 2008. This article, which is excerpted from a longer report, focuses specifically on just one subset of the non-residential PV market: systems hosted (and perhaps owned) by commercial, tax-paying entities. Tax-exempt entities (e.g., non-profits or municipalities) face unique issues and have different financing options at their disposal; readers interested in PV financing options for tax-exempt entities can find more information in the Bolinger report.
Date: February 15, 2009
Creator: Bolinger, Mark A.
Object Type: Article
System: The UNT Digital Library
TRU VU rig instrumentation. [Final report] (open access)

TRU VU rig instrumentation. [Final report]

TRU VU was developed in response to the growing need for real time rig instrumentation that interface various rig systems into a common database. TRU VU is a WITS compatible (Wellsite Information Transfer Standard) system that logs drilling data and MWD data into a common database. Real time data as well as historical data can be viewed from up to eight locations on the rig or from numerous locations in communication with the rig. The TRU VU well monitoring package can be configured to operate manned or unmanned depending on the specific requirements of the operator or drilling contractor. TRU VU does not require a drilling recorder and is totally independent of all rig systems. For example, depth is monitored directly from the draw works and can monitor pipe movement while drilling or tripping. Weight on bit is zeroed automatically on each connection and does not require manual input.
Date: February 15, 1993
Creator: Boone, S. G.
Object Type: Report
System: The UNT Digital Library
TRU VU rig instrumentation (open access)

TRU VU rig instrumentation

TRU VU was developed in response to the growing need for real time rig instrumentation that interface various rig systems into a common database. TRU VU is a WITS compatible (Wellsite Information Transfer Standard) system that logs drilling data and MWD data into a common database. Real time data as well as historical data can be viewed from up to eight locations on the rig or from numerous locations in communication with the rig. The TRU VU well monitoring package can be configured to operate manned or unmanned depending on the specific requirements of the operator or drilling contractor. TRU VU does not require a drilling recorder and is totally independent of all rig systems. For example, depth is monitored directly from the draw works and can monitor pipe movement while drilling or tripping. Weight on bit is zeroed automatically on each connection and does not require manual input.
Date: February 15, 1993
Creator: Boone, S.G.
Object Type: Report
System: The UNT Digital Library
N >= 4 Supergravity Amplitudes from Gauge Theory at Two Loops (open access)

N >= 4 Supergravity Amplitudes from Gauge Theory at Two Loops

We present the full two-loop four-graviton amplitudes in N = 4, 5, 6 supergravity. These results were obtained using the double-copy structure of gravity, which follows from the recently conjectured color-kinematics duality in gauge theory. The two-loop four-gluon scattering amplitudes in N = 0, 1, 2 supersymmetric gauge theory are a second essential ingredient. The gravity amplitudes have the expected infrared behavior: the two-loop divergences are given in terms of the squares of the corresponding one-loop amplitudes. The finite remainders are presented in a compact form. The finite remainder for N = 8 supergravity is also presented, in a form that utilizes a pure function with a very simple symbol.
Date: February 15, 2012
Creator: Boucher-Veronneau, C. & Dixon, L. J.
Object Type: Article
System: The UNT Digital Library
Induction accelerators and free-electron lasers at LLNL: Beam Research Program (open access)

Induction accelerators and free-electron lasers at LLNL: Beam Research Program

Linear induction accelerators have been developed to produce pulses of charged particles at voltages exceeding the capabilities of single-stage, diode-type accelerators and at currents too high rf accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multistage induction machine. The advent of magnetic pulse power systems makes sustained operation at high repetition rates practical, and high-average-power capability is very likely to open up many new applications of induction machines. In Part A of this paper, we survey the US induction linac technology, emphasizing electron machines. We also give a simplified description of how induction machines couple energy to the electron beam to illustrate many general issues that designers of high-brightness and high-average-power induction linacs must consider. We give an example of the application of induction accelerator technology to the relativistic klystron, a power source for high-gradient accelerators. In Part B we address the application of LIAs to free-electron lasers. The multikiloampere peak currents available from linear induction accelerators make high-gain, free-electron laser amplifier configurations feasible. High extraction efficiencies in a single mass of the electron beam are possible if the wiggler parameters are appropriately ''tapered'', as recently demonstrated at millimeter wavelengths on the 4-MeV ELF …
Date: February 15, 1989
Creator: Briggs, R. J.
Object Type: Report
System: The UNT Digital Library
The Pulse Line Ion Accelerator Concept (open access)

The Pulse Line Ion Accelerator Concept

The Pulse Line Ion Accelerator concept was motivated by the desire for an inexpensive way to accelerate intense short pulse heavy ion beams to regimes of interest for studies of High Energy Density Physics and Warm Dense Matter. A pulse power driver applied at one end of a helical pulse line creates a traveling wave pulse that accelerates and axially confines the heavy ion beam pulse. Acceleration scenarios with constant parameter helical lines are described which result in output energies of a single stage much larger than the several hundred kilovolt peak voltages on the line, with a goal of 3-5 MeV/meter acceleration gradients. The concept might be described crudely as an ''air core'' induction linac where the PFN is integrated into the beam line so the accelerating voltage pulse can move along with the ions to get voltage multiplication.
Date: February 15, 2006
Creator: Briggs, Richard J.
Object Type: Article
System: The UNT Digital Library
Environmental Test Activity on the Flight Modules of the GLAST LAT Tracker (open access)

Environmental Test Activity on the Flight Modules of the GLAST LAT Tracker

The GLAST Large Area Telescope (LAT) is a gamma-ray telescope consisting of a silicon micro-strip detector tracker followed by a segmented CsI calorimeter and covered by a segmented scintillator anticoincidence system that will search for {gamma}-rays in the 20 MeV-300 GeV energy range. The results of the environmental tests performed on the flight modules (towers) of the Tracker are presented. The aim of the environmental tests is to verify the performance of the silicon detectors in the expected mission environment. The tower modules are subjected to dynamic tests that simulate the launch environment and thermal vacuum test that reproduce the thermal gradients expected on orbit. The tower performance is continuously monitored during the whole test sequence. The environmental test activity, the results of the tests and the silicon tracker performance are presented.
Date: February 15, 2007
Creator: Brigida, M.; Caliandro, A.; Favuzzi, C.; Fusco, P.; Gargano, F.; Giglietto, N. et al.
Object Type: Article
System: The UNT Digital Library
Performance of the Integrated Tracker Towers of the GLAST Large Area Telescope (open access)

Performance of the Integrated Tracker Towers of the GLAST Large Area Telescope

The GLAST Large Area Telescope (LAT) is a high energy gamma ray observatory, mounted on a satellite that will be own in 2007. The LAT tracker consists of an array of tower modules, equipped with planes of silicon strip detectors (SSDs) interleaved with tungsten converter layers. Photon detection is based on the pair conversion process; silicon strip detectors will reconstruct tracks of electrons and positrons. The instrument is actually being assembled. The first towers have been already tested and integrated at Stanford Linear Accelerator Center (SLAC). An overview of the integration stages of the main components of the tracker and a description of the pre-launch tests will be given. Experimental results on the performance of the tracker towers will be also discussed.
Date: February 15, 2007
Creator: Brigida, M.; Caliandro, A.; Favuzzi, C.; Fusco, P.; Gargano, F.; Giglietto, N. et al.
Object Type: Article
System: The UNT Digital Library