Sample records for bispectral threshold method

  1. Bispectral-Based Methods for Clustering Time Series Jane L. Harvill

    E-Print Network [OSTI]

    Ravishanker, Nalini

    the ratios. As an example, we apply the method to a set of time series of intensities of gamma-ray bursts, some of which exhibit nonlinear behavior; this enables us to identify gamma-ray bursts that may. As an example, we apply the bispectral-based clustering technique to a set of gamma-ray burst (GRB) intensity

  2. Methods for threshold determination in multiplexed assays

    DOE Patents [OSTI]

    Tammero, Lance F. Bentley; Dzenitis, John M; Hindson, Benjamin J

    2014-06-24T23:59:59.000Z

    Methods for determination of threshold values of signatures comprised in an assay are described. Each signature enables detection of a target. The methods determine a probability density function of negative samples and a corresponding false positive rate curve. A false positive criterion is established and a threshold for that signature is determined as a point at which the false positive rate curve intersects the false positive criterion. A method for quantitative analysis and interpretation of assay results together with a method for determination of a desired limit of detection of a signature in an assay are also described.

  3. Some Noncommutative Matrix Algebras Arising in the Bispectral Problem

    E-Print Network [OSTI]

    F. Alberto Grünbaum

    2014-07-24T23:59:59.000Z

    I revisit the so called "bispectral problem" introduced in a joint paper with Hans Duistermaat a long time ago, allowing now for the differential operators to have matrix coefficients and for the eigenfunctions, and one of the eigenvalues, to be matrix valued too. In the last example we go beyond this and allow both eigenvalues to be matrix valued.

  4. Sequential Threshold Control in Descent Splitting Methods for ...

    E-Print Network [OSTI]

    2014-11-21T23:59:59.000Z

    Nov 5, 2014 ... coordinate-wise steps together with a special threshold control. ... the computational process and leads to the (forward-backward) splitting ...

  5. USE OF A SPATIALLY ADAPTIVE THRESHOLDING METHOD FOR THE CONDITION MONITORING OF A WIND TURBINE GEARBOX

    E-Print Network [OSTI]

    Boyer, Edmond

    USE OF A SPATIALLY ADAPTIVE THRESHOLDING METHOD FOR THE CONDITION MONITORING OF A WIND TURBINE.Antoniadou@sheffield.ac.uk ABSTRACT Condition monitoring of wind turbine gearboxes is an important practice in order to de- termine the state of the wind turbine drivetrain. In this way reparative actions could be taken whenever needed

  6. Organic thin film devices with stabilized threshold voltage and mobility, and method for preparing the devices

    DOE Patents [OSTI]

    Nastasi, Michael Anthony; Wang, Yongqiang; Fraboni, Beatrice; Cosseddu, Piero; Bonfiglio, Annalisa

    2013-06-11T23:59:59.000Z

    Organic thin film devices that included an organic thin film subjected to a selected dose of a selected energy of ions exhibited a stabilized mobility (.mu.) and threshold voltage (VT), a decrease in contact resistance R.sub.C, and an extended operational lifetime that did not degrade after 2000 hours of operation in the air.

  7. Threshold voltage extraction circuit

    E-Print Network [OSTI]

    Hoon, Siew Kuok

    2000-01-01T23:59:59.000Z

    to that of the saturation method. However, instead of fixing Vos ? Vos, the drain current is measured as a function of Vos while Vns is fixed at a constant low voltage of 100mV to ensure operation in the linear MOSFET region. Neglecting channel length modulation effect... transistors are layout next to the DUT of the NMOS and PMOS Vr extraction circuits respectively for extraction of Vr via graphical means. GRAPHICAL METHOD OF THE THRESHOLD-VOLTAGE MEASUREMENT Using the graphical method, the characteristics of 4n versus Vos...

  8. Optimization Online - Sequential Threshold Control in Descent ...

    E-Print Network [OSTI]

    Igor Konnov

    2014-11-21T23:59:59.000Z

    Nov 21, 2014 ... Sequential Threshold Control in Descent Splitting Methods for Decomposable Optimization Problems. Igor Konnov(konn-igor ***at*** ya.ru).

  9. ROBUST THRESHOLDING BASED ON WAVELETS AND THINNING ALGORITHMS FOR DEGRADED CAMERA IMAGES

    E-Print Network [OSTI]

    Dupont, Stéphane

    Copernic, 7000 Mons, Belgium ABSTRACT This paper describes a thresholding method for degraded docu- ments

  10. Multiphoton detachment of H- near the one-photon threshold: Exterior complex-scaling–generalized pseudospectral method for complex quasienergy resonances

    E-Print Network [OSTI]

    Chu, Shih-I; Telnov, Dmitry A.

    1999-04-01T23:59:59.000Z

    We perform a nonperturbative study of the multiphoton above-threshold detachment of H- in the presence of 1.640??m and 1.908??m laser fields by means of the non-Hermitian Floquet formalism. The laser parameters used are related to the recent...

  11. On the measurement of laser-induced plasma breakdown thresholds

    SciTech Connect (OSTI)

    Brieschenk, Stefan [Centre for Hypersonics, The University of Queensland, Brisbane 4072 (Australia)] [Centre for Hypersonics, The University of Queensland, Brisbane 4072 (Australia); Kleine, Harald; O'Byrne, Sean [The University of New South Wales Canberra, The Australian Defence Force Academy, Canberra 2600 (Australia)] [The University of New South Wales Canberra, The Australian Defence Force Academy, Canberra 2600 (Australia)

    2013-09-07T23:59:59.000Z

    The breakdown threshold of a gas exposed to intense laser-radiation is a function of gas and laser properties. Breakdown thresholds reported in the literature often vary greatly and these differences can partially be traced back to the method that is typically used to determine breakdown thresholds. This paper discusses the traditional method used to determine breakdown thresholds and the potential errors that can arise using this approach, and presents an alternative method which can yield more accurate data especially when determining breakdown thresholds as functions of gas pressure.

  12. Top Threshold Physics

    E-Print Network [OSTI]

    Andre H. Hoang

    2006-04-21T23:59:59.000Z

    Running a future Linear Collider at the top pair threshold allows for precise measurements of the mass, the widths and the couplings of the top quark. I give a nontechnical review on recent theoretical developments and the theory status in top threshold physics concerning QCD corrections and top quark finite lifetime and electroweak effects. I also discuss threshold physics in the context of measurements of the top Yukawa coupling from $e^+e^-\\to t\\bar t H$ and of squark pair production.

  13. Threshold for dissipative fission

    SciTech Connect (OSTI)

    Thoennessen, M.; Bertsch, G.F. (National Superconducting Cyclotron Laboratory and Department of Physics Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States) Department of Physics, FM-15, University of Washington, Seattle, Washington 98105 (United States))

    1993-12-27T23:59:59.000Z

    We examine the empirical domain of validity of statistical theory, as applied to fission data on prefission neutron, charged particle, and [gamma]-ray multiplicities. Systematics are found in the threshold excitation energy for the appearance of nonstatistical fission. From the data on systems with not too high fissility,, the relevant phenomenological parameter is the ratio of the threshold temperature [ital T][sub thresh] to the (temperature dependent) fission barrier height [ital E][sub bar([ital T])]. The statistical model reproduces the data for [ital T][sub thresh]/[ital E][sub bar([ital T])[lt]0.26][plus minus]0.05 but underpredicts the multiplicities at higher [ital T][sub thresh]/[ital E][sub bar([ital T])] independent of mass and fissility of the systems.

  14. Hard Thresholding Pursuit Algorithms: Number of Iterations

    E-Print Network [OSTI]

    Hitczenko, Pawel

    algorithms do provide alternative methods. We consider here the hard thresholding pursuit (HTP) algorithm [6 us now recall that (HTP) consists in constructing a sequence (xn) of s-sparse vectors, starting absolute entries of xn-1 + A (y - Axn-1 ),(HTP1) xn := argmin{ y - Az 2, supp(z) Sn },(HTP2) until

  15. Wavelet thresholding using generalized cross Maarten Jansen, Adhemar Bultheel

    E-Print Network [OSTI]

    Jansen, Maarten

    Wavelet thresholding using generalized cross validation Maarten Jansen, Adhemar Bultheel October 1997 Abstract De­noising algorithms based on wavelet thresholding replace small wavelet coefficients,this method assumes uncorrelated noise and or­ thogonal wavelet transforms. It turns out that extension

  16. Considerations when applying thresholds to

    E-Print Network [OSTI]

    Wind erosion thresholds are crossed as gap sizes increase due to grass mortality (often, but not always (wind erosion) or property (gap size) Resilience begins to decline ­ increasing probability (wind erosion) or property (gap size) "THRESHOLD" #12;Probabilityofautogenicrecovery Status of key

  17. Resilience, Triggers, Feedbacks and Thresholds

    E-Print Network [OSTI]

    High Low Energy capture efficiency Nutrient retention efficiencyResource flows captured by organic Australia's Rangelands. CSIRO, Australia. Pp. 158. #12;Ecological Thresholds ``Thresholds are boundaries-functional Recovery requires vegetation manipulation Water capture efficiencyHigh Low High Low High Low Moderate High

  18. STEPLENGTH THRESHOLDS FOR INVARIANCE PRESERVING ...

    E-Print Network [OSTI]

    2014-06-25T23:59:59.000Z

    ods, i.e., the coefficient matrix of the discrete system is derived from the Taylor expansion of eAc?t, we present an algorithm to derive a valid steplength threshold.

  19. Summing tree graphs at threshold

    SciTech Connect (OSTI)

    Brown, L.S. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1992-11-15T23:59:59.000Z

    The solution of the classical field equation generates the sum of all tree graphs. We show that the classical equation reduces to an easily solved ordinary differential equation for certain multiparticle threshold amplitudes and compute these amplitudes.

  20. Fractal Superconductivity near Localization Threshold

    E-Print Network [OSTI]

    Fominov, Yakov

    Fractal Superconductivity near Localization Threshold Mikhail Feigel'man Landau Institute, Moscow-electron states are extended but fractal and populate small fraction of the whole volume How BCS theory should be modified to account for eigenstates fractality ? #12;Mean-Field Eq. for Tc #12;#12;3D Anderson model: = 0

  1. MACHINE MONITORING USING PROBABILITY THRESHOLDS

    E-Print Network [OSTI]

    Pollock, Stephen

    MACHINE MONITORING USING PROBABILITY THRESHOLDS AND SYSTEM OPERATING CHARACTERISTICS Stephen M and Jeffrey M. Alden G.M. R&D Center Warren, MI 48090 IOE Tech Report 95-14 #12;1. Introduction We a discrete-part production machine, with the objective of effectively determining when to shut the machine

  2. WAVELET-BASED DENOISING BY CUSTOMIZED THRESHOLDING Byung-Jun Yoon and P. P. Vaidyanathan

    E-Print Network [OSTI]

    Yoon, Byung-Jun

    WAVELET-BASED DENOISING BY CUSTOMIZED THRESHOLDING Byung-Jun Yoon and P. P. Vaidyanathan Dept, nonlinear methods, especially those based on wavelets have become increasingly popular, due to a number of ad- vantages over the linear methods. It has been shown that wavelet- thresholding has near

  3. Reduced lasing threshold from organic dye microcavities

    E-Print Network [OSTI]

    Akselrod, G. M.

    We demonstrate an unexpected tenfold reduction in the lasing threshold of an organic vertical microcavity under subpicosecond optical excitation. In contrast to conventional theory of lasing, we find that the lasing threshold ...

  4. Compositional threshold for Nuclear Waste Glass Durability

    SciTech Connect (OSTI)

    Kruger, Albert A. [Pacific Northwest National Lab., Richland, WA (United States); Farooqi, Rahmatullah [Pohang Univ. of Science and Technology, (Korea, Republic of); Hrma, Pavel R. [Pacific Northwest National Lab., Richland, WA (United States), Pohang Univ. of Science and Technology, (Korea, Republic of)

    2013-04-24T23:59:59.000Z

    Within the composition space of glasses, a distinct threshold appears to exist that separates "good" glasses, i.e., those which are sufficiently durable, from "bad" glasses of a low durability. The objective of our research is to clarify the origin of this threshold by exploring the relationship between glass composition, glass structure and chemical durability around the threshold region.

  5. Error Channels and the Threshold for Fault-tolerant Quantum Computation

    E-Print Network [OSTI]

    Bryan Eastin

    2007-10-15T23:59:59.000Z

    This dissertation treats the topics of threshold calculation, ancilla construction, and non-standard error models. Chapter 2 introduces background material ranging from quantum mechanics to classical coding to thresholds for quantum computation. In Chapter 3 numerical and analytical means are used to generate estimates of and bounds on the threshold given an error model described by a restricted stochastic Pauli channel. Chapter 4 develops a simple, flexible means of estimating the threshold and applies it to some cases of interest. Finally, a novel method of ancilla construction is proposed in Chapter 5, and the difficulties associated with implementing it are discussed.

  6. Tumor delineation using PET in head and neck cancers: Threshold contouring and lesion volumes

    E-Print Network [OSTI]

    Yetisgen-Yildiz, Meliha

    PET/CT patient images. The intensity value of the threshold contour level that returns 100Tumor delineation using PET in head and neck cancers: Threshold contouring and lesion volumes Eric as a function of the reconstruction method, smoothing, and lesion size in head and neck cancer patients using

  7. Molecular dynamics simulation of threshold displacement energies...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    experimental estimates in ceramics. Citation: Moreira PA, R Devanathan, J Yu, and WJ Weber.2009."Molecular dynamics simulation of threshold displacement energies in...

  8. Wind-Blown Sand: Threshold of Motion

    E-Print Network [OSTI]

    Swann, Christy Michelle

    2014-11-12T23:59:59.000Z

    ....................................................................................... 43 13 Bedload trap designed for this study .................................................................................. 45 14 Schematic of internal adjustable chimney adjusted to the height of the surface... predicting the threshold for wind-blown sand in natural environments are rooted in the original wind tunnel work of Bagnold (1936). He introduced an empirically-calibrated model of the threshold using shear velocity, 𝑢?: a height independent variable...

  9. Hierarchical Threshold Secret Sharing Tamir Tassa

    E-Print Network [OSTI]

    Beimel, Amos

    Hierarchical Threshold Secret Sharing Tamir Tassa Abstract We consider the problem of threshold secret sharing in groups with hierarchical structure. In such settings, the secret is shared among and the presence of higher level participants is imperative to allow the recovery of the common secret. Even though

  10. Hierarchical Threshold Secret Sharing Tamir Tassa #

    E-Print Network [OSTI]

    Tassa, Tamir

    Hierarchical Threshold Secret Sharing Tamir Tassa # December 6, 2006 Abstract We consider the problem of threshold secret sharing in groups with hierarchical structure. In such settings, the secret of the common secret. Even though secret sharing in hierarchical groups has been studied extensively in the past

  11. Hierarchical Threshold Secret Sharing Tamir Tassa

    E-Print Network [OSTI]

    Tassa, Tamir

    Hierarchical Threshold Secret Sharing Tamir Tassa Division of Computer Science, The Open University tassa@yahoo.com Abstract. We consider the problem of threshold secret sharing in groups with hierarchical structure. In such settings, the secret is shared among a group of participants

  12. Hierarchical Threshold Secret Sharing Tamir Tassa

    E-Print Network [OSTI]

    Tassa, Tamir

    Hierarchical Threshold Secret Sharing Tamir Tassa December 6, 2006 Abstract We consider the problem of threshold secret sharing in groups with hierarchical structure. In such settings, the secret is shared among and the presence of higher level participants is imperative to allow the recovery of the common secret. Even though

  13. Simulating Threshold Circuits by Majority Circuits \\Lambda

    E-Print Network [OSTI]

    Karpinski, Marek

    Simulating Threshold Circuits by Majority Circuits \\Lambda Mikael Goldmann y Numerical Analysis, and Kailath proved super­linear lower bounds on the number of wires in constant­depth majority circuits­size depth 2 majority circuit. In general we show that a polynomial­size, depth­ d threshold circuit can

  14. Multiphoton above-threshold detachment of Li-: Exterior-complex-scaling– generalized-pseudospectral method for calculations of complex-quasienergy resonances in Floquet formulation of time-dependent density-functional theory

    E-Print Network [OSTI]

    Telnov, Dmitry A.; Chu, Shih-I

    2002-10-25T23:59:59.000Z

    We extend the exterior-complex-scaling–generalized-pseudospectral (ECSGPS) method [D. A. Telnov and S. I. Chu, Phys. Rev. A 59, 2864 (1999)] to the nonperturbative calculations of complex-quasienergy resonances of many-electron quantum systems...

  15. Beyond Kennicott : perceptions of threshold, conceptions of distance

    E-Print Network [OSTI]

    Bull, Steven Keith

    1997-01-01T23:59:59.000Z

    Threshold: The thesis explores descriptions of threshold. Threshold is not an ordinary space. It relates to the here and the there and the understanding of distance. It is the phenomena of distance, no matter how close ...

  16. Threshold Effects Beyond the Standard Model

    E-Print Network [OSTI]

    Tomasz R. Taylor

    2006-12-12T23:59:59.000Z

    In this contribution to the Festschrift celebrating Gabriele Veneziano on his 65th birthday, I discuss the threshold effects of extra dimensions and their applications to physics beyond the standard model, focusing on superstring theory.

  17. A threshold type Cerenkov radiation detector

    E-Print Network [OSTI]

    Winningham, John David

    1965-01-01T23:59:59.000Z

    A THRESHOLD TYPE CERENKOV RADIATION DETECTOR A Thesis By JOHN DAVID WINNINGHAN Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree of NASTER OF SCIENCE May, 1965 Ha/or Sub...)ect: Physics A THRESHOLD TYPE CERENKOV RADIATION DETECTOR A Thesis By JOHN DAVID WINNINGHAM Approved as to style and content by: 3 v (Chairman of Committee) j' ) Heqd of Department) (Member) (Member) May, 1965 i. '. 11648 ACKNOWLEDGEIKNTS I wish...

  18. Experimental determination of transparency current density and estimation of the threshold current of semiconductor quantum well lasers

    SciTech Connect (OSTI)

    Chen, T.R.; Eng, L.E.; Zhuang, Y.H.; Yariv, A. (California Institute of Technology, Pasadena, California 91125 (US))

    1990-03-12T23:59:59.000Z

    An experimental method for determining the transparency current density of semiconductor quantum well lasers is demonstrated in a strained-layer InGaAs/GaAs single quantum well laser system. The experimental results are then used as a practical guide to the study of ultralow threshold lasers. A threshold current as low as 0.75 mA is observed.

  19. Fractal Threshold Behavior in Vacuum Gravitational Collapse

    E-Print Network [OSTI]

    Sebastian J. Szybka; Tadeusz Chmaj

    2008-04-02T23:59:59.000Z

    We present the numerical evidence for fractal threshold behavior in the five dimensional vacuum Einstein equations satisfying the cohomogeneity-two triaxial Bianchi type-IX ansatz. In other words, we show that a flip of the wings of a butterfly may influence the process of the black hole formation.

  20. Multiple Sclerosis Luminance Threshold and Measurements

    E-Print Network [OSTI]

    Foster, David H.

    Multiple Sclerosis Luminance Threshold and Measurements of Temporal Characteristics of Vision Definite MS + 6/9 - + + 7/50/F Recurrent ON + 6/6 + - + 8/47/F Definite MS + 6/6 + + + · Luminance to te t the temporal properties of vi Ion were equalized with respect to Individual luminance thresh

  1. Reliability of underwater hearing thresholds in pinnipeds

    E-Print Network [OSTI]

    Reichmuth, Colleen

    Reliability of underwater hearing thresholds in pinnipeds Brandon L. Southall Long Marine and certain testing parameters (e.g., equipment and research personnel), measured underwater hearing (0.2­6.4 kHz). These data address the reliability of acoustic signal detection measurements over time

  2. How to identify the structure of near-threshold states from the line shape

    E-Print Network [OSTI]

    Guo-Ying Chen; Wen-Sheng Huo; Qiang Zhao

    2014-10-29T23:59:59.000Z

    We revisit the compositeness theorem proposed by Weinberg in an effective field theory (EFT) and explore criteria which are sensitive to the structure of $S$-wave threshold states. On a general basis, we show that the wave function renormalization constant $Z$, which is the probability of finding an elementary component in the wave function of a threshold state, can be explicitly introduced in the description of the threshold state. As an application of this EFT method, we describe the near-threshold line shape of the $D^{\\ast 0}\\bar D^0$ invariant mass spectrum in $B\\rightarrow D^{\\ast 0}\\bar D^0 K$ and determine a nonvanishing value of $Z$. It suggests that the $X(3872)$ as a candidate of the $D^{\\ast 0}\\bar D^0$ molecule may still contain a small $c\\bar{c}$ core. This elementary component, on the one hand, explains its production in the $B$ meson decay via a short-distance mechanism, and on the other hand, is correlated with the $D^{\\ast 0}\\bar D^0$ threshold enhancement observed in the $D^{\\ast 0}\\bar D^0$ invariant mass distributions. Meanwhile, we also show that if $Z$ is non-zero, the near-threshold enhancement of the $D^{\\ast 0}\\bar D^0$ mass spectrum in the $B$ decay will be driven by the short-distance production mechanism. This conclusion is still true even if the long-distance production is enhanced by some unexpected mechanism.

  3. Threshold photodetachment spectroscopy of negative ions

    SciTech Connect (OSTI)

    Kitsopoulos, T.N.

    1991-12-01T23:59:59.000Z

    This thesis is concerned with the development and application of high resolution threshold photodetachment spectroscopy of negative ions. Chapter I deals with the principles of our photodetachment technique, and in chapter II a detailed description of the apparatus is presented. The threshold photodetachment spectra of I{sup {minus}}, and SH{sup {minus}}, presented in the last sections of chapter II, indicated that a resolution of 3 cm{sup {minus}1} can be achieved using our technique. In chapter III the threshold photodetachment spectroscopy study of the transition state region of I + HI and I + Di reactions is discussed. Our technique probes the transition state region directly, and the results of our study are the first unambiguous observations of reactive resonances in a chemical reaction. Chapters IV, V and VI are concerned with the spectroscopy of small silicon and carbon clusters. From our spectra we were able to assign electronic state energies and vibrational frequencies for the low lying electronics states of Si{sub n} (n=2,3,4), C{sub 5} and their corresponding anions.

  4. Optimization Online - A Counterexample to “Threshold Boolean form ...

    E-Print Network [OSTI]

    James Luedtke

    2015-01-02T23:59:59.000Z

    Jan 2, 2015 ... ... to “Threshold Boolean form for joint probabilistic constraints with random technology matrix” ... the Mathematical Optmization Society.

  5. Fault-Tolerant Thresholds for Encoded Ancillae with Homogeneous Errors

    E-Print Network [OSTI]

    Bryan Eastin

    2006-11-14T23:59:59.000Z

    I describe a procedure for calculating thresholds for quantum computation as a function of error model given the availability of ancillae prepared in logical states with independent, identically distributed errors. The thresholds are determined via a simple counting argument performed on a single qubit of an infinitely large CSS code. I give concrete examples of thresholds thus achievable for both Steane and Knill style fault-tolerant implementations and investigate their relation to threshold estimates in the literature.

  6. Ionization Thresholds of Small Carbon Clusters: Tunable VUVExperiments and Theory

    SciTech Connect (OSTI)

    Belau, Leonid; Wheeler, Steven E.; Ticknor, Brian W.; Ahmed,Musahid; Leone, Stephen R.; Allen, Wesley D.; Schaefer III, Henry F.; Duncan, Michael A.

    2007-07-31T23:59:59.000Z

    Small carbon clusters (Cn, n = 2-15) are produced in amolecular beam by pulsed laser vaporization and studied with vacuumultraviolet (VUV) photoionization mass spectrometry. The required VUVradiation in the 8-12 eV range is provided by the Advanced Light Source(ALS) at the Lawrence Berkeley National Laboratory. Mass spectra atvarious ionization energies reveal the qualitative relative abundances ofthe neutral carbon clusters produced. By far the most abundant species isC3. Using the tunability of the ALS, ionization threshold spectra arerecorded for the clusters up to 15 atoms in size. The ionizationthresholds are compared to those measured previously with charge-transferbracketing methods. To interpret the ionization thresholds for differentcluster sizes, new ab initio calculations are carried out on the clustersfor n = 4-10. Geometric structures are optimized at the CCSD(T) levelwith cc-pVTZ (or cc-pVDZ) basis sets, and focal point extrapolations areapplied to both neutral and cation species to determine adiabatic andvertical ionization potentials. The comparison of computed and measuredionization potentials makes it possible to investigate the isomericstructures of the neutral clusters produced in this experiment. Themeasurements are inconclusive for the n = 4-6 species because ofunquenched excited electronic states. However, the data provide evidencefor the prominence of linear structures for the n = 7, 9, 11, 13 speciesand the presence of cyclic C10.

  7. Tumor delineation using PET in head and neck cancers: Threshold contouring and lesion volumes

    SciTech Connect (OSTI)

    Ford, Eric C.; Kinahan, Paul E.; Hanlon, Lorraine; Alessio, Adam; Rajendran, Joseph; Schwartz, David L.; Phillips, Mark [University of Washington, Department of Radiation Oncology, 1959 N. E. Pacific Street, Seattle, Washington 98195 (United States) and Puget Sound Veterans Administration, 18801 S. Columbian Way, Seattle, Washington 98195 (United States); University of Washington, Department of Radiology, 1959 N. E. Pacific Street, Seattle, Washington 98195 (United States); University of Washington, Department of Radiation Oncology, 1959 N. E. Pacific Street, Seattle, Washington 98195 and School of Physics, University College Dublin (Ireland); University of Washington, Department of Radiology, 1959 N. E. Pacific Street, Seattle, Washington 98195 (United States); University of Texas, M.D. Anderson Cancer Center, Department of Radiation Oncology, 1515 Holcombe Blvd., Houston, Texas 77030 and Puget Sound Veterans Administration, 1880 S. Columbian Way, Seattle, Washington 98195 (United States); University of Washington, Department of Radiation Oncology, 1959 N. E. Pacific Street, Seattle, Washington 98195 (United States)

    2006-11-15T23:59:59.000Z

    Tumor boundary delineation using positron emission tomography (PET) is a promising tool for radiation therapy applications. In this study we quantify the uncertainties in tumor boundary delineation as a function of the reconstruction method, smoothing, and lesion size in head and neck cancer patients using FDG-PET images and evaluate the dosimetric impact on radiotherapy plans. FDG-PET images were acquired for eight patients with a GE Advance PET scanner. In addition, a 20 cm diameter cylindrical phantom with six FDG-filled spheres with volumes of 1.2 to 26.5 cm{sup 3} was imaged. PET emission scans were reconstructed with the OSEM and FBP algorithms with different smoothing parameters. PET-based tumor regions were delineated using an automatic contouring function set at progressively higher threshold contour levels and the resulting volumes were calculated. CT-based tumor volumes were also contoured by a physician on coregistered PET/CT patient images. The intensity value of the threshold contour level that returns 100% of the actual volume, I{sub V100}, was measured. We generated intensity-modulated radiotherapy (IMRT) plans for an example head and neck patient, treating 66 Gy to CT-based gross disease and 54 Gy to nodal regions at risk, followed by a boost to the FDG-PET-based tumor. The volumes of PET-based tumors are a sensitive function of threshold contour level for all patients and phantom datasets. A 5% change in threshold contour level can translate into a 200% increase in volume. Phantom data indicate that I{sub V100} can be set as a fraction, f, of the maximum measured uptake. Fractional threshold values in the cylindrical water phantom range from 0.23 to 0.51. Both the fractional threshold and the threshold-volume curve are dependent on lesion size, with lesions smaller than approximately 5 cm{sup 3} displaying a more pronounced sensitivity and larger fractional threshold values. The threshold-volume curves and fractional threshold values also depend on the reconstruction algorithm and smoothing filter with more smoothing requiring a higher fractional threshold contour level. The threshold contour level affects the tumor size, and therefore the ultimate boost dose that is achievable with IMRT. In an example head and neck IMRT plan, the D95 of the planning target volume decreased from 7770 to 7230 cGy for 42% vs 55% contour threshold levels. PET-based tumor volumes are strongly affected by the choice of threshold level. This can have a significant dosimetric impact. The appropriate threshold level depends on lesion size and image reconstruction parameters. These effects should be carefully considered when using PET contour and/or volume information for radiotherapy applications.

  8. The AMS-01 Aerogel Threshold Cherenkov counter

    E-Print Network [OSTI]

    D. Barancourt; F. Barao; G. Barbier; G. Barreira; M. Buenerd; G. Castellini; E. Choumilov; J. Favier; N. Fouque; A. Gougas; V. Hermel; R. Kossakowski; G. Laborie; G. Laurenti; S. -C. Lee; F. Mayet; B. Meillon; Y. -T. Oyang; V. Plyaskin; V. Pojidaev; C. Rossin; D. Santos; F. Vezzu; J. P. Vialle

    2000-10-12T23:59:59.000Z

    The Alpha Magnetic Spectrometer in a precursor version (AMS-01), was flown in June 1998 on a 51.6 degrees orbit and at altitudes ranging between 320 and 390 km, on board of the space shuttle Discovery (flight STS-91). AMS-01 included an Aerogel Threshold Cherenkov counter (ATC) to separate antiprotons from electrons and positrons from protons, for momenta below 3.5 GeV/c. This paper presents a description of the ATC counter and reports on its performances during the flight STS-91.

  9. Quark mass thresholds in QCD thermodynamics

    E-Print Network [OSTI]

    M. Laine; Y. Schroder

    2006-05-05T23:59:59.000Z

    We discuss radiative corrections to how quark mass thresholds are crossed, as a function of the temperature, in basic thermodynamic observables such as the pressure, the energy and entropy densities, and the heat capacity of high temperature QCD. The indication from leading order that the charm quark plays a visible role at surprisingly low temperatures, is confirmed. We also sketch a way to obtain phenomenological estimates relevant for generic expansion rate computations at temperatures between the QCD and electroweak scales, pointing out where improvements over the current knowledge are particularly welcome.

  10. Threshold 21 Model | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries PvtStratosolarTharaldson Ethanol LLCEnergyoThornwood, NewThreshold 21 Model Jump

  11. Threshold shift and above-threshold multiphoton ionization of atomic hydrogen in intense laser fields

    E-Print Network [OSTI]

    Chu, Shih-I; Cooper, J.

    1985-11-01T23:59:59.000Z

    , while hE, =e F /4m co~ = e F s/2m' is the continuum threshold upshift. 1 e 2@2 4 Itt CO and the threshold shift as (3) 0.28 0.01 0.025 0.05 0.075 —1.185(—2) —6.732( —2) —2.036( —1) —3.306( —1) 1.735{—2) 1.085( —1) 4.339(—1) 9.762( —1) 2.92( —2) 1.76( —1...

  12. Superlinear threshold detectors in quantum cryptography

    SciTech Connect (OSTI)

    Lydersen, Lars; Maroey, Oystein; Skaar, Johannes; Makarov, Vadim [Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway); University Graduate Center, NO-2027 Kjeller (Norway); Jain, Nitin; Wittmann, Christoffer; Marquardt, Christoph; Leuchs, Gerd [Max Planck Institute for the Science of Light, Guenther-Scharowsky-Strasse 1/Bau 24, DE-91058 Erlangen (Germany); Institut fuer Optik, Information und Photonik, University of Erlangen-Nuremberg, Staudtstrasse 7/B2, DE-91058 Erlangen (Germany)

    2011-09-15T23:59:59.000Z

    We introduce the concept of a superlinear threshold detector, a detector that has a higher probability to detect multiple photons if it receives them simultaneously rather than at separate times. Highly superlinear threshold detectors in quantum key distribution systems allow eavesdropping the full secret key without being revealed. Here, we generalize the detector control attack, and analyze how it performs against quantum key distribution systems with moderately superlinear detectors. We quantify the superlinearity in superconducting single-photon detectors based on earlier published data, and gated avalanche photodiode detectors based on our own measurements. The analysis shows that quantum key distribution systems using detector(s) of either type can be vulnerable to eavesdropping. The avalanche photodiode detector becomes superlinear toward the end of the gate. For systems expecting substantial loss, or for systems not monitoring loss, this would allow eavesdropping using trigger pulses containing less than 120 photons per pulse. Such an attack would be virtually impossible to catch with an optical power meter at the receiver entrance.

  13. Measurement and interpretation of threshold stress intensity factors for steels in high-pressure hydrogen gas.

    SciTech Connect (OSTI)

    Dadfarnia, Mohsen (University of Illinois at Urbana-Champaign, Urbana, IL); Nibur, Kevin A.; San Marchi, Christopher W.; Sofronis, Petros (University of Illinois at Urbana-Champaign, Urbana, IL); Somerday, Brian P.; Foulk, James W., III; Hayden, Gary A. (CP Industries, McKeesport, PA)

    2010-07-01T23:59:59.000Z

    Threshold stress intensity factors were measured in high-pressure hydrogen gas for a variety of low alloy ferritic steels using both constant crack opening displacement and rising crack opening displacement procedures. The sustained load cracking procedures are generally consistent with those in ASME Article KD-10 of Section VIII Division 3 of the Boiler and Pressure Vessel Code, which was recently published to guide design of high-pressure hydrogen vessels. Three definitions of threshold were established for the two test methods: K{sub THi}* is the maximum applied stress intensity factor for which no crack extension was observed under constant displacement; K{sub THa} is the stress intensity factor at the arrest position for a crack that extended under constant displacement; and K{sub JH} is the stress intensity factor at the onset of crack extension under rising displacement. The apparent crack initiation threshold under constant displacement, K{sub THi}*, and the crack arrest threshold, K{sub THa}, were both found to be non-conservative due to the hydrogen exposure and crack-tip deformation histories associated with typical procedures for sustained-load cracking tests under constant displacement. In contrast, K{sub JH}, which is measured under concurrent rising displacement and hydrogen gas exposure, provides a more conservative hydrogen-assisted fracture threshold that is relevant to structural components in which sub-critical crack extension is driven by internal hydrogen gas pressure.

  14. The (Unstable) Threshold of Black Hole Formation

    E-Print Network [OSTI]

    M. W. Choptuik

    1998-03-23T23:59:59.000Z

    In recent years it has become apparent that intriguing phenomenology exists at the threshold of black hole formation in a large class of general relativistic collapse models. This phenomenology, which includes scaling, self-similarity and universality, is largely analogous to statistical mechanical critical behaviour, a fact which was first noted empirically, and subsequently clarified by perturbative calculations which borrow on ideas and techniques from dynamical systems theory and renormalization group theory. This contribution, which closely parallels my talk at the conference, consists of an overview of the considerable ``zoo''' of critical solutions which have been discovered thus far, along with a brief discussion of how we currently understand the nature of these solutions from the point of view of perturbation theory.

  15. Optical ranked-order filtering using threshold decomposition

    DOE Patents [OSTI]

    Allebach, J.P.; Ochoa, E.; Sweeney, D.W.

    1987-10-09T23:59:59.000Z

    A hybrid optical/electronic system performs median filtering and related ranked-order operations using threshold decomposition to encode the image. Threshold decomposition transforms the nonlinear neighborhood ranking operation into a linear space-invariant filtering step followed by a point-to-point threshold comparison step. Spatial multiplexing allows parallel processing of all the threshold components as well as recombination by a second linear, space-invariant filtering step. An incoherent optical correlation system performs the linear filtering, using a magneto-optic spatial light modulator as the input device and a computer-generated hologram in the filter plane. Thresholding is done electronically. By adjusting the value of the threshold, the same architecture is used to perform median, minimum, and maximum filtering of images. A totally optical system is also disclosed. 3 figs.

  16. Optical ranked-order filtering using threshold decomposition

    DOE Patents [OSTI]

    Allebach, Jan P. (West Lafayette, IN); Ochoa, Ellen (Pleasanton, CA); Sweeney, Donald W. (Alamo, CA)

    1990-01-01T23:59:59.000Z

    A hybrid optical/electronic system performs median filtering and related ranked-order operations using threshold decomposition to encode the image. Threshold decomposition transforms the nonlinear neighborhood ranking operation into a linear space-invariant filtering step followed by a point-to-point threshold comparison step. Spatial multiplexing allows parallel processing of all the threshold components as well as recombination by a second linear, space-invariant filtering step. An incoherent optical correlation system performs the linear filtering, using a magneto-optic spatial light modulator as the input device and a computer-generated hologram in the filter plane. Thresholding is done electronically. By adjusting the value of the threshold, the same architecture is used to perform median, minimum, and maximum filtering of images. A totally optical system is also disclosed.

  17. anisotropy instability thresholds: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    these fluctuations are enhanced along the temperature anisotropy thresholds of the mirror, proton oblique firehose, and ion cyclotron instabilities. In addition, the measured...

  18. Laser thermoelastic generation in metals above the melt threshold

    SciTech Connect (OSTI)

    Every, A. G. [School of Physics, University of the Witwatersrand, PO Wits 2050 (South Africa)] [School of Physics, University of the Witwatersrand, PO Wits 2050 (South Africa); Utegulov, Z. N. [Department of Physics, School of Science and Technology, Nazarbayev University, Astana 010000 (Kazakhstan)] [Department of Physics, School of Science and Technology, Nazarbayev University, Astana 010000 (Kazakhstan); Veres, I. A. [RECENDT Research Center for Non-Destructive Testing GmbH, A-4040 Linz (Austria)] [RECENDT Research Center for Non-Destructive Testing GmbH, A-4040 Linz (Austria)

    2013-11-28T23:59:59.000Z

    An approach is presented for calculating thermoelastic generation of ultrasound in a metal plate exposed to nanosecond pulsed laser heating, sufficient to cause melting but not ablation. Detailed consideration is given to the spatial and temporal profiles of the laser pulse, penetration of the laser beam into the sample, the appearance and subsequent growth and then contraction of the melt pool, and the time dependent thermal conduction in the melt and surrounding solid throughout. The excitation of the ultrasound takes place during and shortly after the laser pulse and occurs predominantly within the thermal diffusion length of a micron or so beneath the surface. It is shown how, because of this, the output of the thermal simulations can be expressed as axially symmetric transient radial and normal surface force distributions. The epicentral displacement response to these force distributions is obtained by two methods, the one based on the elastodynamic Green's functions for plate geometry determined by the Cagniard generalized ray method and the other using a finite element numerical method. The two approaches are in very close agreement. Numerical simulations are reported on the epicentral displacement response of a 3.12 mm thick tungsten plate irradiated with a 4 ns pulsed laser beam with Gaussian spatial profile, at intensities below and above the melt threshold.

  19. A Threshold Autoregressive Model for Wholesale Electricity Prices

    E-Print Network [OSTI]

    A Threshold Autoregressive Model for Wholesale Electricity Prices B. Ricky Rambharat, Department the price of wholesale electricity soared to an unprecedented level of $7,500 per MwH (see [14-order threshold autoregressive model (TAR(1)) for wholesale electricity prices. (For discussion of TAR models, see

  20. Characterizing Ideal Weighted Threshold Secret Amos Beimel1

    E-Print Network [OSTI]

    Beimel, Amos

    Characterizing Ideal Weighted Threshold Secret Sharing Amos Beimel1 , Tamir Tassa1,2 , and Enav Science, The Open University, Ra'anana, Israel. Abstract. Weighted threshold secret sharing was introduced by Shamir in his seminal work on secret sharing. In such settings, there is a set of users where each user

  1. A threshold Cherenkov detector for K separation using silica aerogel

    E-Print Network [OSTI]

    Magiera, Andrzej

    A threshold Cherenkov detector for Kþ =pþ separation using silica aerogel R. Siudak a,b , A August 2008 Keywords: Threshold Cherenkov detector Silica aerogel Reaction pp ! Kþ ðLp� Kþ =pþ separation in the focal plane of a magnetic spectrograph. Silica aerogel with refractive index of n ¼ 1:05 is applied

  2. d Original Contribution IDENTIFYING THE INERTIAL CAVITATION THRESHOLD AND SKULL

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    d Original Contribution IDENTIFYING THE INERTIAL CAVITATION THRESHOLD AND SKULL EFFECTS IN AVESSEL unknown. To investigate the pressure threshold for inertial cavitation of pre- formed microbubbles during sonication, passive cavitation detection in conjunction with B-mode imaging was used. A cerebral vessel

  3. An Efficient and Accurate Method for Evaluating Time Series Similarity

    E-Print Network [OSTI]

    Michigan, University of

    , the methods whose matching criteria is bounded by a specified threshold value, such as the LCSS and the EDR to evaluate such threshold value techniques, including LCSS and EDR. Using FTSE, we show that these techniques in a framework that can evaluate a richer range of threshold-based scoring techniques, of which EDR and LCSS

  4. Radioactive sealed sources: Reasonable accountability, exemption, and licensing activity thresholds -- A technical basis

    SciTech Connect (OSTI)

    Lee, D.W. [Los Alamos National Lab., NM (United States); Shingleton, K.L. [Lawrence Livermore National Lab., CA (United States)

    1996-07-01T23:59:59.000Z

    Perhaps owing to their small size and portability, some radiation accidents/incidents have involved radioactive sealed sources (RSSs). As a result, programs for the control and accountability of RSSs have come to be recommended and emplaced that essentially require RSSs to be controlled in a manner different from bulk, unsealed radioactive material. Crucially determining the total number of RSSs for which manpower-intensive radiation protection surveillance is provided is the individual RSS activity above which such surveillance is required and below which such effort is not considered cost effective. Individual RSS activity thresholds are typically determined through scenarios which impart a chosen internal or external limiting dose to Reference Man under specified exposure conditions. The resultant RSS threshold activity levels have meaning commensurate with the assumed scenario exposure parameters, i.e., if they are realistic and technically based. A review of how the Department of Energy (DOE), the International Atomic Energy Agency (IAEA), and the Nuclear Regulatory Commission (NRC) have determined their respective accountability, exemption, and licensing threshold activity values is provided. Finally, a fully explained method using references readily available to practicing health physicists is developed using realistic, technically-based calculation parameters by which RSS threshold activities may be locally generated.

  5. Observed physical processes in mechanical tests of PBX9501 and recomendations for experiments to explore a possible plasticity/damage threshold

    SciTech Connect (OSTI)

    Buechler, Miles A. [Los Alamos National Laboratory

    2012-05-02T23:59:59.000Z

    This memo discusses observations that have been made in regards to a series of monotonic and cyclic uniaxial experiments performed on PBX9501 by Darla Thompson under Enhanced Surveilance Campaign support. These observations discussed in Section Cyclic compression observations strongly suggest the presence of viscoelastic, plastic, and damage phenomena in the mechanical response of the material. In Secton Uniaxial data analysis and observations methods are discussed for separating out the viscoelastic effects. A crude application of those methods suggests the possibility of a critical stress below which plasticity and damage may be negligible. The threshold should be explored because if it exists it will be an important feature of any constitutive model. Additionally, if the threshold exists then modifications of experimental methods may be feasible which could potentially simplify future experiments or provide higher quality data from those experiments. A set of experiments to explore the threshold stress are proposed in Section Exploratory tests program for identifying threshold stress.

  6. Near-threshold photodetachment of heavy alkali-metal anions

    SciTech Connect (OSTI)

    Bahrim, C.; Thumm, U.; Khuskivadze, A.A.; Fabrikant, I.I. [Department of Physics, Kansas State University, Manhattan, Kansas 66506-2604 (United States); Department of Chemistry and Physics, Lamar University, Beaumont, Texas 77710-10046 (United States); Department of Physics, Kansas State University, Manhattan, Kansas 66506-2604 (United States); Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588-0111 (United States)

    2002-11-01T23:59:59.000Z

    We calculate near-threshold photodetachment cross sections for Rb{sup -}, Cs{sup -}, and Fr{sup -} using the Pauli equation method with a model potential describing the effective electron-atom interaction. Parameters of the model potential are fitted to reproduce ab initio scattering phase shifts obtained from Dirac R-matrix calculations. Special care is taken to formulate the boundary conditions near the atomic nucleus for solving the Pauli equation, based on the analytic solution of the Dirac equation for a Coulomb potential. We find a {sup 3}P{sub 1}{sup o} resonance contribution to the photodetachment cross section of Rb{sup -}, Cs{sup -}, and Fr{sup -} ions. Our calculated total photodetachment cross sections for Cs agree with experiments after tuning the resonance position by 2.4 meV. For Rb{sup -} and Fr{sup -} the resonance contribution is much smaller than for Cs. We therefore also provide angle-differential cross sections and asymmetry parameters which are much more sensitive to the resonant contribution than total cross sections.

  7. On the Behavior of the Threshold Operator for Bandlimited Functions

    E-Print Network [OSTI]

    Boche, Holger

    One interesting question is how the good local approximation behavior of the Shannon sampling series for the Paley–Wiener space PW[1 over ?] is affected if the samples are disturbed by the non-linear threshold operator. ...

  8. A Threshold Autoregressive Model for Wholesale Electricity Prices

    E-Print Network [OSTI]

    A Threshold Autoregressive Model for Wholesale Electricity Prices B. Ricky Rambharat Carnegie of wholesale electricity soared to an unprecedented $7,500 per megawatt-hour (MwH) (see FERC, 1998). Models

  9. Applying thresholds to forecast potential biodiversity loss from human development

    E-Print Network [OSTI]

    Hilderbrand, Robert H.

    thresholds to projected increases in residential development in the Middle Patuxent River watershed by 2030 in the Potapsco River watershed of Maryland could result in the loss of nearly 60% of the benthic

  10. Essays on Voluntary Contribution with Private Information and Threshold Uncertainty

    E-Print Network [OSTI]

    Peng, Hui-Chun

    2014-07-08T23:59:59.000Z

    This dissertation concerns individual voluntary contributions in the subscription game with three important model considerations: private information on public good valuations, threshold uncertainty and the timing of the contribution — simultaneous...

  11. Minimum patch size thresholds of reproductive success of songbirds

    E-Print Network [OSTI]

    Butcher, Jerrod Anthony

    2009-05-15T23:59:59.000Z

    1 MINIMUM PATCH SIZE THRESHOLDS OF REPRODUCTIVE SUCCESS OF SONGBIRDS A Dissertation by JERROD ANTHONY BUTCHER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of DOCTOR OF PHILOSOPHY May 2008 Major Subject: Wildlife and Fisheries Sciences 2 MINIMUM PATCH SIZE THRESHOLDS OF REPRODUCTIVE SUCCESS OF SONGBIRDS A Dissertation by JERROD ANTHONY BUTCHER Submitted to the Office...

  12. Effect of shrink fits on threshold speeds of rotordynamic instability

    E-Print Network [OSTI]

    Mir, MD. Mofazzal Hossain

    2001-01-01T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 CHAPTER IV TEST APPARATUS . . . . 13 CHAPTER V RESULTS AND DISCUSSION . . . 17 17 30 42 42 47 5. 1 Rap Test. . 5. 2 Running Test 5. 3 Modeling and the Prcdiction of Threshold Speed of Instability.... . . . . . . . . . . . , . . . . . . . . . . . 5. 3. 1 Matching the Base Case. 5. 3. 2 Gunter's Prediction Using C, q 5. 3. 3 Modeling and Prediction of the Threshold Speed Using the XLTRC Code. . . . 51 5. 4 Prediction of the Onset Speed of Instability for a Tight Inteiference Fit...

  13. Direct Measurement of the Bubble Nucleation Energy Threshold in a CF3I Bubble Chamber

    E-Print Network [OSTI]

    Behnke, E; Brice, S J; Broemmelsiek, D; Collar, J I; Cooper, P S; Crisler, M; Dahl, C E; Fustin, D; Hall, J; Harnish, C; Levine, I; Lippincott, W H; Moan, T; Nania, T; Neilson, R; Ramberg, E; Robinson, A E; Sonnenschein, A; Vázquez-Jáuregui, E; Rivera, R A; Uplegger, L

    2013-01-01T23:59:59.000Z

    We have directly measured the energy threshold and efficiency for bubble nucleation from iodine recoils in a CF3I bubble chamber in the energy range of interest for a dark matter search. These interactions cannot be probed by standard neutron calibration methods, so we develop a new technique by observing the elastic scattering of 12 GeV/c negative pions. The pions are tracked with a silicon pixel telescope and the reconstructed scattering angle provides a measure of the nuclear recoil kinetic energy. The bubble chamber was operated with a nominal threshold of (13.6+-0.6) keV. Interpretation of the results depends on the response to fluorine and carbon recoils, but in general we find agreement with the predictions of the classical bubble nucleation theory. This measurement confirms the applicability of CF3I as a target for spin-independent dark matter interactions and represents a novel technique for calibration of superheated fluid detectors.

  14. Low-energy structure of above-threshold-ionization electron spectra: Role of the Coulomb threshold effect

    E-Print Network [OSTI]

    Telnov, Dmitry A.; Chu, Shih-I

    2011-06-10T23:59:59.000Z

    Recent experimental observations of above-threshold ionization of rare gas atoms and diatomic molecules by midinfrared laser fields [C. I. Blaga et al., Nat. Phys. 5, 335 (2009); W. Quan et al., Phys. Rev. Lett. 103, 093001 ...

  15. Nonclassicality thresholds for multiqubit states: Numerical analysis

    SciTech Connect (OSTI)

    Gruca, Jacek; Zukowski, Marek [Institute of Theoretical Physics and Astrophysics, University of Gdansk, PL-80-952 Gdansk (Poland); Laskowski, Wieslaw [Institute of Theoretical Physics and Astrophysics, University of Gdansk, PL-80-952 Gdansk (Poland); Fakultaet fuer Physik, Ludwig-Maximilians Universitaet Muenchen, D-80799 Muenchen (Germany); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Kiesel, Nikolai [Faculty of Physics, University of Vienna, A-1090 Vienna (Austria); Wieczorek, Witlef; Weinfurter, Harald [Fakultaet fuer Physik, Ludwig-Maximilians Universitaet Muenchen, D-80799 Muenchen (Germany); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Schmid, Christian [Fakultaet fuer Physik, Ludwig-Maximilians Universitaet Muenchen, D-80799 Muenchen (Germany); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); European Organisation for Astronomical Research in the Southern Hemisphere, D-85748 Garching (Germany)

    2010-07-15T23:59:59.000Z

    States that strongly violate Bell's inequalities are required in many quantum-informational protocols as, for example, in cryptography, secret sharing, and the reduction of communication complexity. We investigate families of such states with a numerical method which allows us to reveal nonclassicality even without direct knowledge of Bell's inequalities for the given problem. An extensive set of numerical results is presented and discussed.

  16. Boolean Threshold Networks: Virtues and Limitations for Biological Modeling

    E-Print Network [OSTI]

    Jorge G. T. Zañudo; Maximino Aldana; Gustavo Martínez-Mekler

    2010-11-16T23:59:59.000Z

    Boolean threshold networks have recently been proposed as useful tools to model the dynamics of genetic regulatory networks, and have been successfully applied to describe the cell cycles of \\textit{S. cerevisiae} and \\textit{S. pombe}. Threshold networks assume that gene regulation processes are additive. This, however, contrasts with the mechanism proposed by S. Kauffman in which each of the logic functions must be carefully constructed to accurately take into account the combinatorial nature of gene regulation. While Kauffman Boolean networks have been extensively studied and proved to have the necessary properties required for modeling the fundamental characteristics of genetic regulatory networks, not much is known about the essential properties of threshold networks. Here we study the dynamical properties of these networks with different connectivities, activator-repressor proportions, activator-repressor strengths and different thresholds. Special attention is paid to the way in which the threshold value affects the dynamical regime in which the network operates and the structure of the attractor landscape. We find that only for a very restricted set of parameters, these networks show dynamical properties consistent with what is observed in biological systems. The virtues of these properties and the possible problems related with the restrictions are discussed and related to earlier work that uses these kind of models.

  17. Hadron mass scaling near the s-wave threshold

    E-Print Network [OSTI]

    Tetsuo Hyodo

    2014-12-02T23:59:59.000Z

    The influence of a two-hadron threshold is studied for the hadron mass scaling with respect to some quantum chromodynamics parameters. A quantum mechanical model is introduced to describe the system with a one-body bare state coupled with a single elastic two-body scattering. The general behavior of the energy of the bound and resonance state near the two-body threshold for a local potential is derived from the expansion of the Jost function around the threshold. It is shown that the same scaling holds for the nonlocal potential induced by the coupling to a bare state. In p or higher partial waves, the scaling law of the stable bound state continues across the threshold describing the real part of the resonance energy. In contrast, the leading contribution of the scaling is forbidden by the nonperturbative dynamics near the s-wave threshold. As a consequence, the bound state energy is not continuously connected to the real part of the resonance energy. This universal behavior originates in the vanishing of the field renormalization constant of the zero-energy resonance in the s wave. A proof is given for the vanishing of the field renormalization constant, together with a detailed discussion.

  18. Threshold energy surface and Frenkel-pair resistivity for Cu

    SciTech Connect (OSTI)

    King, W.E.; Merkle, K.L.; Meshii, M.

    1982-01-01T23:59:59.000Z

    In-situ electrical resistivity damage-rate measurements in the high voltage electron microscope have been used to study electron-irradiation-induced defect production in copper single crystals at T < 10/sup 0/K. Analysis of the directional and energy dependence yields a threshold energy surface that is significantly different from those of previous investigations: two pockets of low threshold energy centered at <100> and <110> surrounded by regions of much higher threshold energy. The corresponding damage function exhibits a plateau of 0.6 Frenkel pairs. the present results imply a Frenkel pair resistivity for C of (2.75/sub -0.2//sup +0.6/) x ..cap omega..-cm.

  19. Near-threshold Photoproduction of Phi Mesons from Deuterium

    E-Print Network [OSTI]

    X. Qian; W. Chen; H. Gao; K. Hicks; K. Kramer; J. M. Laget; T. Mibe; Y. Qiang; S. Stepanyan; D. J. Tedeschi; W. Xu; K. P. Adhikari; M. Amaryan; M. Anghinolfi; J. Ball; M. Battaglieri; V. Batourine; I. Bedlinskiy; M. Bellis; A. S. Biselli; C. Bookwalter; D. Branford; W. J. Briscoe; W. K. Brooks; V. D. Burkert; S. L. Careccia; D. S. Carman; P. L. Cole; P. Collins; V. Crede; A. D'Angelo; A. Daniel; N. Dashyan; R. De Vita; E. De Sanctis; A. Deur; B. Dey; S. Dhamija; C. Djalali; D. Doughty; R. Dupre; H. Egiyan; A. El Alaoui; P. Eugenio; S. Fegan; M. Y. Gabrielyan; N. Gevorgyan; G. P. Gilfoyle; K. L. Giovanetti; F. X. Girod; J. T. Goetz; W. Gohn; R. W. Gothe; L. Graham; K. A. Griffioen; M. Guidal; L. Guo; K. Hafidi; H. Hakobyan; C. Hanretty; N. Hassall; M. Holtrop; Y. Ilieva; D. G. Ireland; S. S. Jawalkar; H. S. Jo; K. Joo; D. Keller; M. Khandaker; P. Khetarpal; A. Kim; W. Kim; A. Klein; F. J. Klein; P. Konczykowski; V. Kubarovsky; S. V. Kuleshov; V. Kuznetsov; K. Livingston; D. Martinez; M. Mayer; J. McAndrew; M. E. McCracken; B. McKinnon; C. A. Meyer; K. Mikhailov; T. Mineeva; M. Mirazita; V. Mokeev; B. Moreno; K. Moriya; B. Morrison; H. Moutarde; E. Munevar; P. Nadel-Turonski; A. Ni; S. Niccolai; I. Niculescu; M. R. Niroula; M. Osipenko; A. I. Ostrovidov; R. Paremuzyan; K. Park; S. Park; S. Anefalos Pereira; S. Pisano; O. Pogorelko; S. Pozdniakov; J. W. Price; S. Procureur; D. Protopopescu; G. Ricco; M. Ripani; B. G. Ritchie; G. Rosner; P. Rossi; F. Sabatié; M. S. Saini; C. Salgado; D. Schott; R. A. Schumacher; E. Seder; H. Seraydaryan; Y. G. Sharabian; E. S. Smith; G. D. Smith; D. I. Sober; D. Sokhan; S. S. Stepanyan; P. Stoler; I. I. Strakovsky; S. Strauch; M. Taiuti; C. E. Taylor; S. Tkachenko; M. Ungaro; B . Vernarsky; M. F. Vineyard; E. Voutier; L. B. Weinstein; D. P. Weygand; M. H. Wood; N. Zachariou; L. Zana; J. Zhang; B. Zhao; Z. W. Zhao

    2010-12-14T23:59:59.000Z

    We report the first measurement of the differential cross section on $\\phi$-meson photoproduction from deuterium near the production threshold for a proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson Lab. The measurement was carried out by a triple coincidence detection of a proton, $K^+$ and $K^-$ near the theoretical production threshold of 1.57 GeV. The extracted differential cross sections $\\frac{d\\sigma}{dt}$ for the initial photon energy from 1.65-1.75 GeV are consistent with predictions based on a quasifree mechanism. This experiment establishes a baseline for a future experimental search for an exotic $\\phi$-N bound state from heavier nuclear targets utilizing subthreshold/near-threshold production of $\\phi$ mesons.

  20. Optimal Investment Under Transaction Costs: A Threshold Rebalanced Portfolio Approach

    E-Print Network [OSTI]

    Tunc, Sait

    2012-01-01T23:59:59.000Z

    We study optimal investment in a financial market having a finite number of assets from a signal processing perspective. We investigate how an investor should distribute capital over these assets and when he should reallocate the distribution of the funds over these assets to maximize the cumulative wealth over any investment period. In particular, we introduce a portfolio selection algorithm that maximizes the expected cumulative wealth in i.i.d. two-asset discrete-time markets where the market levies proportional transaction costs in buying and selling stocks. We achieve this using "threshold rebalanced portfolios", where trading occurs only if the portfolio breaches certain thresholds. Under the assumption that the relative price sequences have log-normal distribution from the Black-Scholes model, we evaluate the expected wealth under proportional transaction costs and find the threshold rebalanced portfolio that achieves the maximal expected cumulative wealth over any investment period. Our derivations ca...

  1. Low-Threshold Surface-Passivated Photonic Crystal Nanocavity Laser

    E-Print Network [OSTI]

    Dirk Englund; Hatice Altug; Jelena Vuckovic

    2007-06-21T23:59:59.000Z

    The efficiency and operating range of a photonic crystal laser is improved by passivating the InGaAs quantum well (QW) gain medium and GaAs membrane using an (NH4)S treatment. The passivated laser shows a four-fold reduction in nonradiative surface recombination rate, resulting in a four-fold reduction in lasing threshold. A three-level carrier dynamics model explains the results and shows that lasing threshold is as much determined by surface recombination losses as by the cavity quality factor (Q). Surface passivation therefore appears crucial in operating such lasers under practical conditions.

  2. Very low threshold InGaAsP mesa laser

    SciTech Connect (OSTI)

    Chen, T.R.; Chiu, L.C.; Hasson, A.; Koren, U.; Margalit, S.; Yariv, A.; Yu, K.L.

    1983-05-01T23:59:59.000Z

    Very low threshold currents InGaAsP/InP terrace mesa (T-ME) lasers with an unpassivated surface have been fabricated on semi-insulating (SI) InP substrates. Fabrication of the lasers involves a single-step liquid phase epitaxial (LPE) growth and a simple etching process. Lasers operating in the fundamental transverse mode with threshold currents as low as 6.3 mA (for a cavity length of 250 ..mu..m) have been obtained. Comparison between the unpassivated lasers and those passivated using the mass transport technique is described.

  3. Multiphoton Double Ionization of Ar and Ne Close to Threshold

    SciTech Connect (OSTI)

    Liu Yunquan [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Department of Physics and State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871 (China); Ye Difa; Liu Jie [Center for Applied Physics and Technology, Peking University, 100084 Beijing (China); Institute of Applied Physics and Computational Mathematics, 100088 Beijing (China); Rudenko, A. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Max-Planck Advanced Study Group at CFEL, 22607 Hamburg (Germany); Tschuch, S.; Duerr, M.; Moshammer, R.; Ullrich, J. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Siegel, M.; Morgner, U. [Leibniz Universitaet Hannover, Welfengarten 1, D-30167 Hannover (Germany); Gong Qihuang [Department of Physics and State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871 (China)

    2010-04-30T23:59:59.000Z

    In kinematically complete studies we explore double ionization (DI) of Ne and Ar in the threshold regime (I>3x10{sup 13} W/cm{sup 2}) for 800 nm, 45 fs pulses. The basic differences are found in the two-electron momentum distributions - 'correlation' (CO) for Ne and 'anticorrelation' (ACO) for Ar - that can be partially explained theoretically within a 3D classical model including tunneling. Transverse electron momentum spectra provide insight into 'Coulomb focusing' and point to correlated nonclassical dynamics. Finally, DI threshold intensities, CO as well as ACO regimes are predicted for both targets.

  4. Cryostat for Ultra-low-energy Threshold Germanium Spectrometers

    SciTech Connect (OSTI)

    Aalseth, Craig E.; Bonicalzi, Ricco; Fast, James E.; Hossbach, Todd W.; Orrell, John L.; Overman, Cory T.; VanDevender, Brent A.

    2013-04-01T23:59:59.000Z

    Abstract: This paper presents progress on the development of a cryostat intended to improve upon the low-energy threshold (below 0.5 keV) of p-type point contact germanium gamma-ray spectrometers. Ultra-low energy thresholds are important in the detection of low-energy nuclear recoils, an event class relevant to both dark matter direct detection and measurement of coherent neutrino-nucleus scattering. The cryostat design, including a thermal and electrical-field model, is presented. A prototype cryostat has been assembled and data acquired to evaluate its vacuum and thermal performance.

  5. Cryostat for Ultra-low-energy Threshold Germanium Spectrometers

    E-Print Network [OSTI]

    Craig E. Aalseth; Ricco M. Bonicalzi; James E. Fast; Todd W. Hossbach; John L. Orrell; Cory T. Overman; Brent A. Vandevender

    2012-10-08T23:59:59.000Z

    This paper presents progress on the development of a cryostat intended to improve upon the low-energy threshold (below 0.5 keV) of p-type point contact germanium gamma-ray spectrometers. Ultra-low energy thresholds are important in the detection of low-energy nuclear recoils, an event class relevant to both dark matter direct detection and measurement of coherent neutrino-nucleus scattering. The cryostat design, including a thermal and electrical-field model, is given. A prototype cryostat has been assembled and data acquired to evaluate its vacuum and thermal performance.

  6. Regulon inference without arbitrary thresholds: three levels of sensitivity

    SciTech Connect (OSTI)

    Dubchak, Pavel Novichkov, Elena Stavrovskaya, Dmitry Rodionov, Andrey Mironov, Inna; Rodionov, Dmitry; Mironov, Andrey; Dubchak, Inna; Novichkov, P.S.

    2010-11-15T23:59:59.000Z

    Reconstruction of transcriptional regulatory networks is one of the major challenges facing the bioinformatics community in view of constantly growing number of complete genomes. The comparative genomics approach has been successfully used for the analysis of the transcriptional regulation of many metabolic systems in various bacteria taxa. The key step in this approach is given a position weight matrix, find an optimal threshold for the search of potential binding sites in genomes. In our previous work we proposed an approach for automatic selection of TFBS score threshold coupled with inference of regulon content. In this study we developed two modifications of this approach providing two additional levels of sensitivity.

  7. Far From Threshold Buckling Analysis of Thin Films

    E-Print Network [OSTI]

    Benny Davidovitch; Robert D. Schroll; Dominic Vella; Mokhtar Adda-Bedia; Enrique Cerda

    2010-08-17T23:59:59.000Z

    Thin films buckle easily and form wrinkled states in regions of well defined size. The extent of a wrinkled region is typically assumed to reflect the zone of in-plane compressive stresses prior to buckling, but recent experiments on ultrathin sheets have shown that wrinkling patterns are significantly longer and follow different scaling laws than those predicted by standard buckling theory. Here we focus on a simple setup to show the striking differences between near-threshold buckling and the analysis of wrinkle patterns in very thin films, which are typically far from threshold.

  8. Optical Damage Threshold of Silicon for Ultrafast Infrared Pulses

    SciTech Connect (OSTI)

    Cowan, Benjamin M.; /Tech-X, Boulder /SLAC

    2007-11-28T23:59:59.000Z

    We present measurements of the optical damage threshold of crystalline silicon in air for ultrafast pulses in the near infrared. The wavelengths tested span a range from the telecommunications band at 1550 nm, extending to 2260 nm. We discuss the motivation for the measurements and give theoretical context. We then describe the experimental setup, diagnostics, and procedure. The results show a breakdown threshold of 0.2J/cm{sup 2} at 1550 nm and 1.06 ps FWHM pulse duration, and a weak dependence on wavelength.

  9. The noncommutative QED threshold energy versus the optimum collision energy

    E-Print Network [OSTI]

    Zheng-Mao Sheng; Yongming Fu; Haibo Yu

    2004-02-10T23:59:59.000Z

    Moller Scattering and Bhabha Scattering on noncommutative space-time is restudied. It is shown that the noncommutative correction of scattering cross sections is not monotonous enhancement with the total energy of colliding electrons, there is an optimum collision energy to get the greatest noncommutative correction. Most surprisingly, there is a linear relation between the noncommutative QED threshold energy and the optimum collision energy.

  10. Threshold error rates for the toric and surface codes

    E-Print Network [OSTI]

    D. S. Wang; A. G. Fowler; A. M. Stephens; L. C. L. Hollenberg

    2009-05-05T23:59:59.000Z

    The surface code scheme for quantum computation features a 2d array of nearest-neighbor coupled qubits yet claims a threshold error rate approaching 1% (NJoP 9:199, 2007). This result was obtained for the toric code, from which the surface code is derived, and surpasses all other known codes restricted to 2d nearest-neighbor architectures by several orders of magnitude. We describe in detail an error correction procedure for the toric and surface codes, which is based on polynomial-time graph matching techniques and is efficiently implementable as the classical feed-forward processing step in a real quantum computer. By direct simulation of this error correction scheme, we determine the threshold error rates for the two codes (differing only in their boundary conditions) for both ideal and non-ideal syndrome extraction scenarios. We verify that the toric code has an asymptotic threshold of p = 15.5% under ideal syndrome extraction, and p = 7.8 10^-3 for the non-ideal case, in agreement with prior work. Simulations of the surface code indicate that the threshold is close to that of the toric code.

  11. Topology Control Problems Under Symmetric and Asymmetric Power Thresholds

    E-Print Network [OSTI]

    Krumke, Sven O.

    Topology Control Problems Under Symmetric and Asymmetric Power Thresholds Sven O. Krumke1 , Rui Liu performance guarantees. Previous work on topology control has assumed the symmetric power thresh- old model, NY 12222. Email: rav i@cs . a l bany . edu. Abstract. We consider topology control problems where

  12. An in situ calibration for hearing thresholds Robert H. Withnella

    E-Print Network [OSTI]

    Allen, Jont

    for the accuracy of hearing tests e.g., Voss et al., 2000 . In situ measurement of acoustic signals in the earAn in situ calibration for hearing thresholds Robert H. Withnella Department of Speech and Hearing has historically relied on acoustic calibration in physical assemblies with an input impedance

  13. Novel failure prognostics approach with dynamic thresholds for machine degradation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Novel failure prognostics approach with dynamic thresholds for machine degradation Kamran Javed-processing and prognostics modeling. To estimate RUL of a degrading machinery, prognostics modeling phase requires precise knowledge about failure thresh- old (FT) (or failure definition). Practically, degrading machinery can have

  14. Threshold-Controlled Global Cascading in Wireless Sensor Networks

    E-Print Network [OSTI]

    Varela, Carlos

    Threshold-Controlled Global Cascading in Wireless Sensor Networks Qiming Lu and G. Korniss is a challenging task. Wireless Sensor Networks (WSNs) provide an example where understanding dynamical processes and other wireless ad- hoc networks. First, sensor nodes are often densely deployed (typically 20 sensor per

  15. Effect of shrink fits on threshold speeds of rotordynamic instability 

    E-Print Network [OSTI]

    Al-Baz, Khalid A

    2001-01-01T23:59:59.000Z

    The purpose of this thesis is to study the effect of shrink fits on the threshold speeds of rotor instability. Shrink or press fit components in built-up rotors are known sources of internal friction damping. The internal friction damping increases...

  16. Polymer Collapse, Protein Folding, and the Percolation Threshold

    E-Print Network [OSTI]

    Meirovitch, Hagai

    Polymer Collapse, Protein Folding, and the Percolation Threshold HAGAI MEIROVITCH University (Macromolecules 1989, 22, 3986­3997) to study protein folding, where H and P are the hydrophobic and polar amino; computer simulation; collapse transition; protein folding Introduction The behavior of dilute polymer

  17. Weights of Exact Threshold Functions Laszlo Babai1

    E-Print Network [OSTI]

    Babai, László

    arnsfelt@cs.au.dk 3 Steklov Mathematical Institute podolskii@mi.ras.ru 4 ITCS, Tsinghua University inputs holds. The related class of (linear) threshold functions consist of those Boolean functions that decide whether a real valued linear inequality in their Boolean inputs holds. To be more precise

  18. “Pay What You Want” as Threshold Public Good Provision

    E-Print Network [OSTI]

    Mak, Vincent; Zwick, Rami; Rao, Akshay R.; Pattaratanakun, Jake A.

    2014-12-31T23:59:59.000Z

    ; feedback; market information “PAY WHAT YOU WANT” 2 “Pay What You Want” as Threshold Public Good Provision In a recent post on the Wikimedia Foundation website, Jimmy Wales, co-founder of Wikipedia, pleaded with users to donate to the website so...

  19. Numerical investigation of the threshold for primordial black hole formation

    E-Print Network [OSTI]

    J. C. Niemeyer

    1998-06-02T23:59:59.000Z

    First results of a numerical investigation of primordial black hole formation in the radiation dominated phase of the Early Universe are presented. The simulations follow the gravitational collapse of three different families of high-amplitude density fluctuations imposed at the time of horizon crossing. The threshold for black hole formation, \\delta_{c} \\approx 0.7, is found to be nearly identical for all perturbation families if the control parameter, \\delta, is chosen as the total excess mass within the initial horizon volume. Furthermore, we demonstrate that the scaling of black hole mass with distance from the formation threshold, known to occur in near-critical gravitational collapse, applies to primordial black hole formation.

  20. Lowering the threshold in the DAMA dark matter detector

    SciTech Connect (OSTI)

    Kelso, Chris [Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112 (United States)

    2014-06-24T23:59:59.000Z

    We look at two improvements related to the DAMA/LIBRA dark matter detector. We show how using a more optimized binning scheme of the current data can lead to significantly tighter contraints on the compatible regions of the WIMP parameter space. In addition, the PMT’s of the detector were upgraded in 2010, allowing the low energy threshold to be lowered from 2 keVee to 1 keVee. We examine the implications for the dark matter interpretion of the DAMA modulation with data in this new energy region. Specifically, we focus on how well the degeneracy between the low mass and high mass regions can be removed by this new data. We find that the lower threshold data should rule out one of the two mass ranges in the spin-independent case at a minimum of the 2.6? level in the worst case scenario.

  1. LHC Beam Loss Measurements and Quench Level Abort Threshold Accuracy

    E-Print Network [OSTI]

    Dehning, B; Sapinski, M

    2010-01-01T23:59:59.000Z

    The LHC beam loss measurement system is designed to trigger the beam abort in case the magnet coil transition level from the superconducting to normal conducting sate is approached. The predicted heat deposition in the superconducting coils of the magnets has been determined by particle shower simulation codes, while for transient losses the enthalpy has been calculated. The results have been combined to determine the abort thresholds. Transient loss measurements of the energy depositions of lost protons with injected beams in the LHC are used to determine the accuracy of the beam abort threshold settings. The simulation predictions are reviewed and compared with the measurement results. The relative difference between measurements and simulation are between 30 to 50 %.

  2. On "Sub-Threshold" Reactions Involving Nuclear Fission

    E-Print Network [OSTI]

    M. Goldhaber; R. Shrock

    2000-11-29T23:59:59.000Z

    We analyze reactions of several types that are naively below threshold but can proceed because of the release of binding energy from nuclear fission and occasionally the formation of Coulombic bound states. These reactions include (i) photofission with pion production and (ii) charged current neutrino-nucleus reactions that lead to fission and/or formation of a Coulomb bound state of a $\\mu^-$ with the nucleus of a fission fragment. We comment on the possible experimental observation of these reactions.

  3. Performance Results of the AMS-01 Aerogel Threshold Cherenkov

    E-Print Network [OSTI]

    F. Mayet

    2000-02-16T23:59:59.000Z

    The Alpha Magnetic Spectrometer (AMS) was flown in june 1998 on board of the space shuttle Discovery (flight STS-91) at an altitude ranging between 320 and 390 km. This preliminary version of AMS included an Aerogel Threshold Cherenkov detector (ATC) to separate antiprotons from electron background, for momenta less than 3.5 GeV/c. In this paper, the design and physical principles of ATC will be discussed briefly, then the performance results of the ATC will be presented.

  4. Predicting threshold and location of laser damage on optical surfaces

    DOE Patents [OSTI]

    Siekhaus, Wigbert (Berkeley, CA)

    1987-01-01T23:59:59.000Z

    An apparatus useful in the prediction of the damage threshold of various optical devices, the location of weak spots on such devices and the location, identification, and elimination of optical surface impurities comprising, a focused and pulsed laser, an photo electric detector/imaging means, and a timer. The weak spots emit photoelectrons when subjected to laser intensities that are less than the intensity actually required to produce the damage. The weak spots may be eliminated by sustained exposure to the laser beam.

  5. Thresholded Lasso for high dimensional variable selection and statistical estimation

    E-Print Network [OSTI]

    Zhou, Shuheng

    2010-01-01T23:59:59.000Z

    Given $n$ noisy samples with $p$ dimensions, where $n \\ll p$, we show that the multi-step thresholding procedure based on the Lasso -- we call it the {\\it Thresholded Lasso}, can accurately estimate a sparse vector $\\beta \\in \\R^p$ in a linear model $Y = X \\beta + \\epsilon$, where $X$ is an $n \\times p$ design matrix, and $\\epsilon \\sim N(0, \\sigma^2 I_n)$. We show that under the restricted eigenvalue (RE) condition (Bickel-Ritov-Tsybakov 09), it is possible to achieve the $\\ell_2$ loss within a logarithmic factor of the ideal mean square error one would achieve with an {\\em oracle} while selecting a sufficiently sparse model -- hence achieving {\\it sparse oracle inequalities}; the oracle would supply perfect information about which coordinates are non-zero and which are above the noise level. In some sense, the Thresholded Lasso recovers the choices that would have been made by the $\\ell_0$ penalized least squares estimators, in that it selects a sufficiently sparse model without sacrificing the accuracy in ...

  6. Threshold Corrections to the Bottom Quark Mass Revisited

    E-Print Network [OSTI]

    Archana Anandakrishnan; B. Charles Bryant; Stuart Raby

    2015-01-29T23:59:59.000Z

    Threshold corrections to the bottom quark mass are often estimated under the approximation that tan$\\beta$ enhanced contributions are the most dominant. In this work we revisit this common approximation made to the estimation of the supersymmetric threshold corrections to the bottom quark mass. We calculate the full one-loop supersymmetric corrections to the bottom quark mass and survey a large part of the phenomenological MSSM parameter space to study the validity of considering only the tan$\\beta$ enhanced corrections. Our analysis demonstrates that this approximation underestimates the size of the threshold corrections by $\\sim$12.5% for most of the considered parameter space. We discuss the consequences for fitting the bottom quark mass and for the effective couplings to Higgses. We find that it is important to consider the additional contributions when fitting the bottom quark mass but the modifications to the effective Higgs couplings are typically $\\mathcal{O}$(few)% for the majority of the parameter space considered.

  7. Investigation of the Cause of Low Blister Threshold Temperatures in the RERTR-12 and AFIP-4 Experiments

    SciTech Connect (OSTI)

    Mitchell K Meyer

    2012-06-01T23:59:59.000Z

    Blister–threshold testing of fuel plates is a standard method through which the safety margin for operation of plate-type in research and test reactors is assessed. The blister-threshold temperature is indicative of the ability of fuel to operate at high temperatures for short periods of time (transient conditions) without failure. This method of testing was applied to the newly developed U-Mo monolithic fuel system. Blister annealing studies on the U-Mo monolithic fuel plates began in 2007, with the Reduced Enrichment for Research and Test Reactors (RERTR)-6 experiment, and they have continued as the U-Mo fuel system has evolved through the research and development process. Blister anneal threshold temperatures from early irradiation experiments (RERTR-6 through RERTR-10) ranged from 400 to 500°C. These temperatures were projected to be acceptable for NRC-licensed research reactors and the high-power Advanced Test Reactor (ATR) and the High Flux Isotope Reactor (HFIR) based on current safety-analysis reports (SARs). Initial blister testing results from the RERTR-12 experiment capsules X1 and X2 showed a decrease in the blister-threshold temperatures. Blister threshold temperatures from this experiment ranged from 300 to 400°C. Selected plates from the AFIP-4 experiment, which was fabricated using a process similar to that used to fabricate the RERTR-12 experiment, also underwent blister testing to determine whether results would be similar. The measured blister-threshold temperatures from the AFIP-4 plates fell within the same blister-threshold temperature range measured in the RERTR-12 plates. Investigation of the cause of this decrease in bister threshold temperature is being conducted under the guidance of Idaho National Laboratory PLN-4155, “Analysis of Low Blister Threshold Temperatures in the RERTR-12 and AFIP-4 Experiments,” and is driven by hypotheses. The main focus of the investigation is in the following areas: 1. Fabrication variables 2. Pre-irradiation characterization 3. Irradiation conditions 4. Post-irradiation examination 5. Additional blister testing 6. Mechanical modeling This report documents the preliminary results of this investigation. Several hypotheses can be dismissed as a result of this investigation. Two primary categories of causes remain. The most prominent theory, supported by the data, is that low blister-threshold temperature is the result of mechanical energy imparted on the samples during the fabrication process (hot and cold rolling) without adequate post processing (annealing). The mechanisms are not clearly understood and require further investigation, but can be divided into two categories: • Residual Stress • Undesirable interaction boundary and/or U-Mo microstructure change A secondary theory that cannot be dismissed with the information that is currently available is that a change in the test conditions has resulted in a statistically significant downward shift of measured blister temperature. This report outlines the results of the forensic investigations conducted to date. The data and conclusions presented in this report are preliminary. Definitive cause and effect relationships will be established by future experimental programs.

  8. Threshold model and the latest NA50 data on $J/?$ suppression in Pb+Pb collisions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2003-05-26T23:59:59.000Z

    Using the QGP motivated threshold model, where all the $J/\\psi$'s are suppressed above a threshold density, we have analyzed the latest version of the NA50 data on the centrality dependence of the $J/\\psi$ over Drell-Yan ratio. The data are not well explain in the model, unless the threshold density is largely smeared. Large smeared threshold density effectively excludes creation of any deconfined medium in the collision.

  9. Measurement of the generalized form factors near threshold via ?*p ? n?+ at high Q2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Park, K; Adhikari, K P; Adikaram, D; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Batourine, V; Bedlinskiy, I; Bennett, R P; et al

    2012-03-26T23:59:59.000Z

    We report the first extraction of the pion-nucleon multipoles near the production threshold for the n?+ channel at relatively high momentum transfer (Q2 up to 4.2 GeV2). The dominance of the s-wave transverse multipole (E0+), expected in this region, allowed us to access the generalized form factor G1 within the light-cone sum rule (LCSR) framework as well as the axial form factor GA. The data analyzed in this work were collected by the nearly 4? CEBAF Large Acceptance Spectrometer (CLAS) using a 5.754-GeV electron beam on a proton target. The differential cross section and the ?-N multipole E0+/GD were measuredmore »using two different methods, the LCSR and a direct multipole fit. The results from the two methods are found to be consistent and almost Q2 independent.« less

  10. Measurement of the generalized form factors near threshold via ?*p ? n?+ at high Q2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Park, K; Adhikari, K P; Adikaram, D; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Batourine, V; Bedlinskiy, I; Bennett, R P; Biselli, A S; Bookwalter, C; Boiarinov, S; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Cole, P L; Contalbrigo, M; Crede, V; D'Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Doughty, D; Dupre, R; El Alaoui, A; El Fassi, L; Euginio, P; Fedotov, G; Fradi, A; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gohn, W; Golovatch, E; Graham, L; Griffioen, K A; Guidal, M; Guo, L; Hafidi, K; Hakobyan, H; Hanretty, C; Heddle, D; Hicks, K; Holtrop, M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jenkins, D; Jo, H S; Joo, K; Khandaker, M; Khertarpal, P; Kim, A; Kim, W; Klein, F J; Kubarovsky, A; Kubarovsky, V; Kuhn, S E; Kuleshov, S V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, J D; Markov, N; Mayer, M; McKinnon, B; Mestayer, M D; Meyer, C A; Mineeva, T; Mirazita, M; Mokeev, V; Moutarde, H; Munevar, E; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Park, S; Anefalos Pereira, S; Phelps, E; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Ricco, G; Rimal, D; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Sabati ee, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seraydaryan, H; Sharabian, Y G; Smith, E S; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tian, Y; Tkachenko, S; Trivedi, A; Ungaro, M; Vernarsky, B; Vlassov, A V; Voutier, E; Watts, D P; Weygand, D P; Wood, M H; Zachariou, N; Zhao, B; Zhao, Z W

    2012-03-26T23:59:59.000Z

    We report the first extraction of the pion-nucleon multipoles near the production threshold for the n?+ channel at relatively high momentum transfer (Q2 up to 4.2 GeV2). The dominance of the s-wave transverse multipole (E0+), expected in this region, allowed us to access the generalized form factor G1 within the light-cone sum rule (LCSR) framework as well as the axial form factor GA. The data analyzed in this work were collected by the nearly 4? CEBAF Large Acceptance Spectrometer (CLAS) using a 5.754-GeV electron beam on a proton target. The differential cross section and the ?-N multipole E0+/GD were measured using two different methods, the LCSR and a direct multipole fit. The results from the two methods are found to be consistent and almost Q2 independent.

  11. Measurement of the generalized form factors near threshold via $?^* p \\to n?^+$ at high $Q^2$

    E-Print Network [OSTI]

    Kijun Park; Ralf Gothe; Krishna Adhikari; Dasuni Adikaram-Mudiyanselage; Marco Anghinolfi; Hovhannes Baghdasaryan; Jacques Ball; Marco Battaglieri; Vitaly Baturin; Ivan Bedlinskiy; Robert Bennett; Angela Biselli; Craig Bookwalter; Sergey Boyarinov; Derek Branford; William Briscoe; William Brooks; Volker Burkert; Daniel Carman; Andrea Celentano; Shloka Chandavar; Gabriel Charles; Philip Cole; Marco Contalbrigo; Volker Crede; Annalisa D'Angelo; Aji Daniel; Natalya Dashyan; Raffaella De Vita; Enzo De Sanctis; Alexandre Deur; Chaden Djalali; David Doughty; Raphael Dupre; Ahmed El Alaoui; Lamiaa Elfassi; Paul Eugenio; Gleb Fedotov; Ahmed Fradi; Marianna Gabrielyan; Nerses Gevorgyan; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Wesley Gohn; Evgeny Golovach; Lewis Graham; Keith Griffioen; Michel Guidal; Lei Guo; Kawtar Hafidi; Hayk Hakobyan; Charles Hanretty; David Heddle; Kenneth Hicks; Maurik Holtrop; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Evgeny Isupov; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Mahbubul Khandaker; Puneet Khetarpal; Andrey Kim; Wooyoung Kim; Andreas Klein; Franz Klein; A. Kubarovsky; Valery Kubarovsky; Sebastian Kuhn; Sergey Kuleshov; Nicholas Kvaltine; Kenneth Livingston; Haiyun Lu; Ian MacGregor; Nikolai Markov; Michael Mayer; Bryan McKinnon; Mac Mestayer; Curtis Meyer; Taisiya Mineeva; Marco Mirazita; Viktor Mokeev; Herve Moutarde; Edwin Munevar Espitia; Pawel Nadel-Turonski; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Mikhail Osipenko; Alexander Ostrovidov; Michael Paolone; Luciano Pappalardo; Rafayel Paremuzyan; Seungkyung Park; Sergio Pereira; Evan Phelps; Silvia Pisano; Oleg Pogorelko; Sergey Pozdnyakov; John Price; Sebastien Procureur; Yelena Prok; Giovanni Ricco; Dipak Rimal; Marco Ripani; Barry Ritchie; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Mukesh Saini; Carlos Salgado; Diane Schott; Reinhard Schumacher; Heghine Seraydaryan; Youri Sharabian; Elton Smith; Gregory Smith; Daniel Sober; Daria Sokhan; Samuel Stepanyan; Stepan Stepanyan; Paul Stoler; Igor Strakovski; Steffen Strauch; Mauro Taiuti; Wei Tang; Charles Taylor; Ye Tian; Svyatoslav Tkachenko; Arjun Trivedi; Maurizio Ungaro; Brian Vernarsky; Alexander Vlasov; Eric Voutier; Daniel Watts; Dennis Weygand; Michael Wood; Nicholas Zachariou; Bo Zhao; Zhiwen Zhao; N. Kalantarians; C. E. Hyde

    2012-02-21T23:59:59.000Z

    We report the first extraction of the pion-nucleon multipoles near the production threshold for the $n\\pi^+$ channel at relatively high momentum transfer ($Q^2$ up to 4.2 $\\rm{GeV^2}$). The dominance of the s-wave transverse multipole ($E_{0+}$), expected in this region, allowed us to access the generalized form factor $G_1$ within the light-cone sum rule (LCSR) framework as well as the axial form factor $G_A$. The data analyzed in this work were collected by the nearly $4\\pi$ CEBAF Large Acceptance Spectrometer (CLAS) using a 5.754 $\\rm{GeV}$ electron beam on a proton target. The differential cross section and the $\\pi-N$-multipole $E_{0+}/G_D$ were measured using two different methods, the LCSR and a direct multipole fit. The results from the two methods are found to be consistent and almost $Q^2$ independent.

  12. Estimating inventory thresholds for nuclear facilities using DOE STD-1027-92 Attachment 1 Table A.1 ``Thresholds for Radionuclides``

    SciTech Connect (OSTI)

    Price, D. [Onsite Engineering and Management, Inc. (United States); Hildum, J.S.; Williams, A.C. [Onsite Engineering and Management, Inc. (United States)

    1997-04-01T23:59:59.000Z

    It has recently been reports that Table A.1 of Attachment 1 of DOE STD-1027-92 is being improperly used to determine the Category 3 inventory threshold values for non-reactor nuclear facilities. The concern of this paper is that Safety Analysts and Facility Managers at the Lawrence Livermore National Laboratory (LLNL), as well as at other locations in the DOE Complex, are improperly using the entries in Table A.1. It is noted at this point that the common use of this table is to establish the lower thresholds for both Categories 2 and 3 non-reactor nuclear facilities by considering inventory quantities, as opposed to a postulated accident scenario. This paper will provide insight regarding this error and will show that the error is most likely non-conservative in nature.

  13. A Thesis for the Degree of Master of Science Provably Secure Threshold Blind

    E-Print Network [OSTI]

    Kim, Kwangjo

    A Thesis for the Degree of Master of Science Provably Secure Threshold Blind Signature Scheme Using Secure Threshold Blind Signature Scheme Using Pairings #12;Provably Secure Threshold Blind Signature and Communications University A thesis submitted to the faculty of Information and Commu- nications University

  14. Node-Replacement Policies to Maintain Threshold-Coverage in Wireless Sensor Networks

    E-Print Network [OSTI]

    Vokkarane, Vinod M.

    1 Node-Replacement Policies to Maintain Threshold-Coverage in Wireless Sensor Networks Sachin consider the problem of maintaining a minimum threshold-coverage in a wireless sensor network, while to maintain threshold-coverage in wireless sensor networks. These policies assess the candidature of each

  15. Fatigue threshold R-curves for predicting reliability of ceramics under cyclic loading

    E-Print Network [OSTI]

    Ritchie, Robert

    Fatigue threshold R-curves for predicting reliability of ceramics under cyclic loading J.J. Kruzic for the prediction of reliability in bridging ceramics under cyclic loading conditions based on a fatigue threshold R-curve threshold R-curve may express this crack-size dependence, analogous to the traditional fracture toughness R-curve

  16. A New (k, n)-Threshold Secret Sharing Scheme and Its Extension

    E-Print Network [OSTI]

    A New (k, n)-Threshold Secret Sharing Scheme and Its Extension Jun Kurihara, Shinsaku Kiyomoto)-threshold secret sharing scheme (threshold scheme), a heavy computational cost is required to make n shares and recover the secret. As a solution to this problem, several fast thresh- old schemes have been proposed

  17. Qualitative and analytical results of the bifurcation thresholds to halo orbits

    E-Print Network [OSTI]

    Sara Bucciarelli; Marta Ceccaroni; Alessandra Celletti; Giuseppe Pucacco

    2015-02-01T23:59:59.000Z

    We study the dynamics in the neighborhood of the collinear Lagrangian points in the spatial, circular, restricted three--body problem. We consider the case in which one of the primaries is a radiating body and the other is oblate (although the latter is a minor effect). Beside having an intrinsic mathematical interest, this model is particularly suited for the description of a mission of a spacecraft (e.g., a solar sail) to an asteroid. The aim of our study is to investigate the occurrence of bifurcations to halo orbits, which take place as the energy level is varied. The estimate of the bifurcation thresholds is performed by analytical and numerical methods: we find a remarkable agreement between the two approaches. As a side result, we also evaluate the influence of the different parameters, most notably the solar radiation pressure coefficient, on the dynamical behavior of the model. To perform the analytical and numerical computations, we start by implementing a center manifold reduction. Next, we estimate the bifurcation values using qualitative techniques (e.g. Poincar\\'e surfaces, frequency analysis, FLIs). Concerning the analytical approach, following \\cite{CPS} we implement a resonant normal form, we transform to suitable action-angle variables and we introduce a detuning parameter measuring the displacement from the synchronous resonance. The bifurcation thresholds are then determined as series expansions in the detuning. Three concrete examples are considered and we find in all cases a very good agreement between the analytical and numerical results.

  18. Otsu method and K-means DongjuLiu, JianYu

    E-Print Network [OSTI]

    Wolberg, George

    Otsu method and K-means DongjuLiu, JianYu Department of Computer Science Beijing Jiaotong optimal threshold, while K-means is a local optimal method. Moreover, K-means does not require computing. Therefore, K-means can be more efficiently extended to multilevel thresholding method, two

  19. Threshold irradiation dose for amorphization of silicon carbide

    SciTech Connect (OSTI)

    Snead, L.L.; Zinkle, S.J.

    1997-03-01T23:59:59.000Z

    The amorphization of silicon carbide due to ion and electron irradiation is reviewed with emphasis on the temperature-dependent critical dose for amorphization. The effect of ion mass and energy on the threshold dose for amorphization is summarized, showing only a weak dependence near room temperature. Results are presented for 0.56 MeV silicon ions implanted into single crystal 6H-SiC as a function of temperature and ion dose. From this, the critical dose for amorphization is found as a function of temperature at depths well separated from the implanted ion region. Results are compared with published data generated using electrons and xenon ions as the irradiating species. High resolution TEM analysis is presented for the Si ion series showing the evolution of elongated amorphous islands oriented such that their major axis is parallel to the free surface. This suggests that surface or strain effects may be influencing the apparent amorphization threshold. Finally, a model for the temperature threshold for amorphization is described using the Si ion irradiation flux and the fitted interstitial migration energy which was found to be {approximately}0.56eV. This model successfully explains the difference in the temperature dependent amorphization behavior of SiC irradiated with 0.56 MeV Si{sup +} at 1 x 10{sup -3} dpa/s and with fission neutrons irradiated at 1 x 10{sup -6} dpa/s irradiated to 15 dpa in the temperature range of {approximately}340{+-}10K.

  20. Electron Rescattering in Above-Threshold Photodetachment of Negative Ions

    SciTech Connect (OSTI)

    Gazibegovic-Busuladzic, A. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo, Bosnia and Herzegovina (Bosnia and Herzegowina); Milosevic, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo, Bosnia and Herzegovina (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Strasse 2a, D-12489 Berlin (Germany); Becker, W. [Max-Born-Institut, Max-Born-Strasse 2a, D-12489 Berlin (Germany); Bergues, B.; Hultgren, H.; Kiyan, I. Yu. [Albert-Ludwigs-Universitaet, D-79104 Freiburg (Germany)

    2010-03-12T23:59:59.000Z

    We present experimental and theoretical results on photodetachment of Br{sup -} and F{sup -} in a strong infrared laser field. The observed photoelectron spectra of Br{sup -} exhibit a high-energy plateau along the laser polarization direction, which is identified as being due to the rescattering effect. The shape and the extension of the plateau is found to be influenced by the depletion of negative ions during the interaction with the laser pulse. Our findings represent the first observation of electron rescattering in above-threshold photodetachment of an atomic system with a short-range potential.

  1. Deuteron-deuteron scattering above four-nucleon breakup threshold

    E-Print Network [OSTI]

    Deltuva, A

    2015-01-01T23:59:59.000Z

    Deuteron-deuteron elastic scattering and transfer reactions in the energy regime above four-nucleon breakup threshold are described by solving exact four-particle equations for transition operators. Several realistic nuclear interaction models are used, including the one with effective many-nucleon forces generated by the explicit $\\Delta$-isobar excitation; the Coulomb force between protons is taken into account as well. Differential cross sections, deuteron analyzing powers, outgoing nucleon polarization, and deuteron-to-neutron polarization transfer coefficients are calculated at 10 MeV deuteron energy. Overall good agreement with the experimental data is found. The importance of breakup channels is demonstrated.

  2. Predicting threshold and location of laser damage on optical surfaces

    DOE Patents [OSTI]

    Siekhaus, W.

    1985-02-04T23:59:59.000Z

    Disclosed is an apparatus useful in the prediction of the damage threshold of various optical devices, the location of weak spots on such devices and the location, identification, and elimination of optical surface impurities. The apparatus comprises a focused and pulsed laser, a photo electric detector/imaging means, and a timer. The weak spots emit photoelectrons when subjected to laser intensities that are less than the intensity actually required to produce the damage. The weak spots may be eliminated by sustained exposure to the laser beam.

  3. Near-threshold production of the multi-strange $?^-$ hyperon

    E-Print Network [OSTI]

    P. Chung; N. N. Ajitanand; J. M. Alexander; M. Anderson; D. Best; F. P. Brady; T. Case; W. Caskey; D. Cebra; J. L. Chance; B. Cole; K. Crowe; A. C. Das; J. E. Draper; M. L. Gilkes; S. Gushue; M. Heffner; A. S. Hirsch; E. L. Hjort; W. Holzmann; L. Huo; M. Issah; M. Justice; M. Kaplan; D. Keane; J. C. Kintner; J. Klay; D. Krofcheck; R. A. Lacey; J. Lauret; M. A. Lisa; H. Liu; Y. M. Liu; J. Milan; R. McGrath; Z. Milosevich; G. Odyniec; D. L. Olson; S. Panitkin; N. T. Porile; G. Rai; H. G. Ritter; J. L. Romero; R. Scharenberg; B. Srivastava; N. T. B Stone; T. J. M. Symons; A. Taranenko; J. Whitfield; T. Wienold; R. Witt; L. Wood; W. N. Zhang; H. Oeschler

    2003-07-26T23:59:59.000Z

    The yield for the multi-strange $\\Xi^{-}$ hyperon has been measured in 6 AGeV Au+Au collisions via reconstruction of its decay products $\\pi^{-}$ and $\\Lambda$, the latter also being reconstructed from its daughter tracks of $\\pi^{-}$ and p. The measurement is rather close to the threshold for $\\Xi^{-}$ production and therefore provides an important test of model predictions. The measured yield for $\\Xi^{-}$ and $\\Lambda$ are compared for several centralities. In central collisions the $\\Xi^{-}$ yield is found to be in excellent agreement with statistical and transport model predictions, suggesting that multi-strange hadron production approaches chemical equilibrium in high baryon density nuclear matter.

  4. New VLSI complexity results for threshold gate comparison

    SciTech Connect (OSTI)

    Beiu, V.

    1996-12-31T23:59:59.000Z

    The paper overviews recent developments concerning optimal (from the point of view of size and depth) implementations of COMPARISON using threshold gates. We detail a class of solutions which also covers another particular solution, and spans from constant to logarithmic depths. These circuit complexity results are supplemented by fresh VLSI complexity results having applications to hardware implementations of neural networks and to VLSI-friendly learning algorithms. In order to estimate the area (A) and the delay (T), as well as the classical AT{sup 2}, we shall use the following {open_quote}cost functions{close_quote}: (i) the connectivity (i.e., sum of fan-ins) and the number-of-bits for representing the weights and thresholds are used as closer approximations of the area; while (ii) the fan-ins and the length of the wires are used for closer estimates of the delay. Such approximations allow us to compare the different solutions-which present very interesting fan-in dependent depth-size and area-delay tradeoffs - with respect to AT{sup 2}.

  5. Damage thresholds of fluoride multilayers at 355 nm

    SciTech Connect (OSTI)

    Chow, R.; Kozlowski, M.R.; Loomis, G.E.; Rainer, F.

    1992-10-01T23:59:59.000Z

    Fluoride multilayer coatings were evaluated for use in 355 nm high reflector applications. The LaF[sub 3]/Na[sub 3]AlF[sub 6], NdF[sub 3]/Na[sub 3]AlF[sub 6] and GdF[sub 3]/Na[sub 3]AlF[sub 6] multilayers had laser damage thresholds of 20, 17.9 and 7.4 (measured at 10-ns pulsewidths), respectively. High tensile stresses in the coatings restricted this evaluation to only 5-layer-pair partial reflectors (49--52%).The LaF[sub 3]/Na[sub 3]AlF[sub 6], NdF[sub 3]/Na[sub 3]Al[sub 6] and GdF[sub 3]/Na[sub 3]AlF[sub 6] multilayers had tensile stresses of [approximately] 1.1 [times] 109, 1.3 [times] 109 and 9.3 [times] 10[sup 8] dynes/cm[sup 2], respectively. Substrate material and glow-discharge processing of the substrates were found to influence the density of stress-induced coating fractures and damage thresholds in some cases. If stress fracturing and scatter can be controlled, these fluoride material combinations are suited for 3[omega] applications.

  6. $J/?$ suppression in the threshold model and QGP formation time

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2007-09-03T23:59:59.000Z

    In the QGP motivated threshold model, in addition to the normal nuclear absorption, $J/\\psi$'s are subjected to an additional "anomalous" suppression. We have analysed the recently published PHENIX data on the participant number dependence of the nuclear modification factor for $J/\\psi$'s in Au+Au collisions and extracted the anomalous suppression required to explain the data. At mid rapidity $J/\\psi$'s are anomalously suppressed only above a threshold density $n_c$=3.73 fm$^{-2}$. The forward rapidity data on the otherhand require that $J/\\psi$'s are continuously "anomalously" suppressed. The analysis strongly indicate that in mid rapidity $J/\\psi$'s are suppressed in a deconfined medium. Using the PHENIX data on the participant number dependence of the Bjorken energy density, we have also estimated the QGP formation time. For critical temperature $T_c$=192 MeV, estimated QGP formation time ranges between 0.06-0.08 fm/c.

  7. Femtosecond pulse damage thresholds of dielectric coatings in vacuum

    SciTech Connect (OSTI)

    Michelle D. Shinn, Duy N. Nguyen, Luke A. Emmert ,Paul Schwoebel, Dinesh Patel, Carmen S. Menoni, Wolfgang Rudolph

    2011-03-01T23:59:59.000Z

    At 10-7 Torr, the multiple femtosecond pulse damage threshold, F(?), is about 10% of the single pulse damage fluence F(1) for hafnia and silica films compared to about 65% and 50%, respectively, at 630 Torr. In contrast, the single-pulse damage threshold is pressure independent. The decrease of F(?) with decreasing air pressure correlates with the water vapor and oxygen content of the ambient gas with the former having the greater effect. The decrease in F(?) is likely associated with an accumulation of defects derived from oxygen deficiency, for example vacancies. From atmospheric air pressure to pressures of {approx}3 x 10{sup -6} Torr, the damage 'crater' starts deterministically at the center of the beam and grows in diameter as the fluence increases. At pressure below 3x10-6 Torr, damage is initiated at random 'sites' within the exposed area in hafnia films, while the damage morphology remains deterministic in silica films. A possible explanation is that absorbing centers are created at predisposed sample sites in hafnia, for example at boundaries between crystallites, or crystalline and amorphous phases.

  8. S-wave threshold in electron attachment - observations and cross sections in CCl4 and SF6 at ultralow electron energies

    SciTech Connect (OSTI)

    Chutjian, A.; Alajajian, S.H.

    1985-05-01T23:59:59.000Z

    The threshold photoionization method was used to study low-energy electron attachment phenomena in and cross sections of CCl4 and SF6 compounds, which have applications in the design of gaseous dielectrics and diffuse discharge opening switches. Measurements were made at electron energies from below threshold to 140 meV at resolutions of 6 and 8 meV. A narrow resolution-limited structure was observed in electron attachment to CCl4 and SF6 at electron energies below 10 meV, which is attributed to the divergence of the attachment cross section in the limit epsilon, l approaches zero. The results are compared with experimental collisional-ionization results, electron-swarm unfolded cross sections, and earlier threshold photoionization data. 34 refs.

  9. The pp->K+ n Sigma+ reaction near threshold

    E-Print Network [OSTI]

    Yu. Valdau; V. Koptev; S. Barsov; M. Büscher; S. Dymov; M. Hartmann; A. Kacharava; S. Merzliakov; S. Mikirtychyants; A. Mussgiller; M. Nekipelov; R. Schleichert; H. Ströher; C. Wilkin

    2007-03-27T23:59:59.000Z

    Inclusive K+ production in proton-proton collisions has been measured at a beam energy of 2.16 GeV using the COSY-ANKE magnetic spectrometer. The resulting spectrum, as well as those corresponding to K+ p and K+ pi+ correlated pairs, can all be well described using consistent values of the total cross sections for the pp->K+ p Lambda, pp->K+ p Sigma0, and pp->K+ n Sigma+ reactions. While the resulting values for Lambda and Sigma0 production are in good agreement with world data, our value for the total Sigma+ production cross section, sigma(pp->K+ n Sigma+) = 2.5+/-0.6(stat)+/-0.4(syst) mkb at an excess energy of epsilon=129 MeV, could only be reconciled with other recently published data if there were a highly unusual near--threshold behaviour.

  10. Threshold Verification Technique for Network Intrusion Detection System

    E-Print Network [OSTI]

    Faizal, M A; Shahrin, S; Robiah, Y; Rahayu, S Siti; Nazrulazhar, B

    2009-01-01T23:59:59.000Z

    Internet has played a vital role in this modern world, the possibilities and opportunities offered are limitless. Despite all the hype, Internet services are liable to intrusion attack that could tamper the confidentiality and integrity of important information. An attack started with gathering the information of the attack target, this gathering of information activity can be done as either fast or slow attack. The defensive measure network administrator can take to overcome this liability is by introducing Intrusion Detection Systems (IDSs) in their network. IDS have the capabilities to analyze the network traffic and recognize incoming and on-going intrusion. Unfortunately the combination of both modules in real time network traffic slowed down the detection process. In real time network, early detection of fast attack can prevent any further attack and reduce the unauthorized access on the targeted machine. The suitable set of feature selection and the correct threshold value, add an extra advantage for I...

  11. The Metastability Threshold for Modified Bootstrap Percolation in d Dimensions

    E-Print Network [OSTI]

    Alexander E. Holroyd

    2006-04-03T23:59:59.000Z

    In the modified bootstrap percolation model, sites in the cube {1,...,L}^d are initially declared active independently with probability p. At subsequent steps, an inactive site becomes active if it has at least one active nearest neighbour in each of the d dimensions, while an active site remains active forever. We study the probability that the entire cube is eventually active. For all d>=2 we prove that as L\\to\\infty and p\\to 0 simultaneously, this probability converges to 1 if L=exp^{d-1} (lambda+epsilon)/p, and converges to 0 if L=exp^{d-1} (lambda-epsilon)/p, for any epsilon>0. Here exp^n denotes the n-th iterate of the exponential function, and the threshold lambda equals pi^2/6 for all d.

  12. Nanowire-based ternary transistor by threshold-voltage manipulation

    SciTech Connect (OSTI)

    Han, Junebeom; Lim, Taekyung; Bong, Jihye; Seo, Keumyoung; Ju, Sanghyun, E-mail: shju@kgu.ac.kr [Department of Physics, Kyonggi University, Suwon, Gyeonggi-Do 443-760 (Korea, Republic of); Kim, Sunkook [Department of Electronics and Radio Engineering, Kyung Hee University, Yongin, Gyeonggi-Do 446-701 (Korea, Republic of)

    2014-04-07T23:59:59.000Z

    We report on a ternary device consisting of two nanowire channels that have different threshold voltage (V{sub th}) values and show that three current stages can be produced. A microscale laser-beam shot was utilized to selectively anneal the nanowire channel area to be processed, and the amount of V{sub th} shift could be controlled by adjusting the laser wavelength. Microscale laser annealing process could control V{sub th} of the individual nanowire transistors while maintaining the other parameters the constant, such as the subthreshold slope, on–off current ratio, and mobility. This result could provide a potential for highly integrated and high-speed ternary circuits.

  13. Triple photoionization of Ne and Ar near threshold

    SciTech Connect (OSTI)

    Bluett, J.B.; Wehlitz, R. [Synchrotron Radiation Center, UW-Madison, Stoughton, Wisconsin 53589 (United States); Lukic, D. [Institute of Physics, 11001 Belgrade (Serbia and Montenegro)

    2004-04-01T23:59:59.000Z

    The triple-photoionization cross section of neon and argon near threshold has been investigated by ion time-of-flight spectrometry. We applied the Wannier power law to our data and confirmed the theoretical Wannier exponent in the cases of Ne and Ar. Our data also agree with previous findings regarding the Wannier exponent and its range of validity for Ne. However, the Wannier power law exhibits a much smaller range of validity of 2 eV for Ar compared to 5 eV for Ne. Also, in contrast to a previous experiment, we do not find a 'second' power law but a gradual decrease of the exponent above the range of validity of the Wannier power law.

  14. Reexamination of an anomaly in near-threshold pair production

    SciTech Connect (OSTI)

    De Braeckeleer, L.; Adelberger, E.G.; Garcia, A. (Physics Department FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1992-11-01T23:59:59.000Z

    We investigated a reported anomaly in near-threshold pair production, using radioactive sources to measure the {gamma}+Ge{r arrow}{ital e}{sup +}+{ital e}{sup {minus}}+Ge cross-section at {ital E}{sub {gamma}}=1063, 1086, 1112, 1173, 1213, 1299, 1332, and 1408 keV. Although the data agree with the theory (numerical calculations based on an exact partial-wave formulation for a screened central potential) at the higher energies, the data lie above the theory at 1063, 1082, and 1112 keV. The discrepancy is reduced by including the final-state Coulomb interaction between the {ital e}{sup +} and {ital e}{sup {minus}}.

  15. The "Supercritical Pile" Model of GRB: Thresholds, Polarization, Time Lags

    E-Print Network [OSTI]

    Demosthenes Kazanas; Markos Georganopoulos; Apostolos Mastichiadis

    2003-11-21T23:59:59.000Z

    The essence of the ``Supercritical Pile'' model is a process for converting the energy stored in the relativistic protons of a Relativistic Blast Wave (RBW) of Lorentz factor $\\Gamma$ into electron -- positron pairs of similar Lorentz factor, while at the same time emitting most of the GRB luminosity at an energy $E_p \\simeq 1$ MeV. This is achieved by scattering the synchrotron radiation emitted by the RBW in an upstream located ``mirror'' and then re-intercepting it by the RBW. The repeated scatterings of radiation between the RBW and the ``mirror'', along with the threshold of the pair production reaction $p \\gamma \\to p e^-e^+$, lead to a maximum in the GRB luminosity at an energy $E_p \\simeq 1$ MeV, {\\sl independent of the value of $\\Gamma$}. Furthermore, the same threshold implies that the prompt $\\gamma-$ray emission is only possible for $\\Gamma$ larger than a minimum value, thereby providing a ``natural'' account for the termination of this stage of the GRB as the RBW slows down. Within this model the $\\gamma-$ray ($E \\sim 100$ keV -- 1 MeV) emission process is due to Inverse Compton scattering and it is thus expected to be highly polarized if viewed at angles $\\theta \\simeq 1/\\Gamma$ to the RBW's direction of motion. Finally, the model also predicts lags in the light curves of the lower energy photons with respect to those of higher energy; these are of purely kinematic origin and of magnitude $\\Delta t \\simeq 10^{-2}$ s, in agreement with observation.

  16. Ultimate limit in low threshold quantum well GaAlAs semiconductor lasers

    SciTech Connect (OSTI)

    Lau, K.Y.; Derry, P.L.; Yariv, A.

    1988-01-11T23:59:59.000Z

    Gain measurements were performed on buried heterostructure single quantum well lasers to ascertain the transparency current density, which represents a basic limit in the threshold current. By using the optimal design approach, a lowest threshold of 0.55 mA in a 120-..mu..m-long device was achieved. Modulation of the low threshold laser by a pseudorandom digital stream at 1.3 Gbit/s without current bias is demonstrated.

  17. Bulk optical damage thresholds for doped and undoped, crystalline and ceramic yttrium aluminum garnet

    SciTech Connect (OSTI)

    Do, Binh T.; Smith, Arlee V.

    2009-06-20T23:59:59.000Z

    We measured the bulk optical damage thresholds of pure and Nd-doped ceramic yttrium aluminum garnet (YAG), and of pure, Nd-doped, Cr-doped, and Yb-doped crystalline YAG. We used 9.9 ns, 1064 nm, single-longitudinal mode, TEM00 pulses, to determine that the breakdown thresholds are deterministic, with multiple-pulse thresholds ranging from 1.1 to 2.2 kJ/cm{sup 2}.

  18. A thermal bistability-based method for optimization of ultra-low threshold microlasers

    E-Print Network [OSTI]

    monolithic cavity exhibits a thermal non- linearity, due to self-heating by the minute optical power

  19. Die POT Methode (Peaks over Threshold) Definition 18 (Die verallgemeinerte Pareto Verteilung (GPD))

    E-Print Network [OSTI]

    Dragoti-Ã?ela, Eranda

    MDA(H)) Sein IR. Die untenstehenden Aussagen sind ¨aquivalent: (i) F MDA(H) (ii) Es existiert eine weitere Charakterisierung von MDA(H)) Sei IR. Folgende Aussagen sind ¨aquivalent: (i) F MDA(H) (ii) Es Verteilungsfunktion F MDA(H) f¨ur IR. · W¨ahle eine hohe Schwelle u (unter Verwendung von geeigneten stat

  20. Laser-induced damage threshold of silicon in millisecond, nanosecond, and picosecond regimes

    SciTech Connect (OSTI)

    Wang, X.; Shen, Z. H.; Lu, J.; Ni, X. W. [School of Science, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2010-08-15T23:59:59.000Z

    Millisecond, nanosecond, and picosecond laser pulse induced damage thresholds on single-crystal are investigated in this study. The thresholds of laser-induced damage on silicon are calculated theoretically for three pulse widths based on the thermal damage model. An axisymmetric mathematical model is established for the transient temperature field of the silicon. Experiments are performed to test the damage thresholds of silicon at various pulse widths. The results indicate that the damage thresholds obviously increase with the increasing of laser pulse width. Additionally, the experimental results agree well with theoretical calculations and numerical simulation results.

  1. Flow-induced tube vibration thresholds in heat exchangers from shellside water tests

    SciTech Connect (OSTI)

    Halle, H.; Chenoweth, J.M.; Wambsganss, M.W.

    1984-01-01T23:59:59.000Z

    Typical industrial shell-and-tube heat exchanger configurations are investigated experimentally for the occurrence of potentially damaging tube vibration as a function of flowrate. The effort is part of a program to develop vibration avoidance criteria to be integrated and optimized with the advanced thermal, hydraulic, and mechanical design methods now available. The tests use a 0.6-m (2-ft)-diameter, 3.7-m (12-ft)-long shell containing a removable tube bundle whose components are readily rearranged or replaced. The 15 different full tube bundle configurations tested represent various combinations of parameters: triangular or square tube layout patterns with different orientations to the flow, number of crosspasses, sizes of nozzles, plain or finned tubes. All bundles have 19-mm (0.75-in.)-diameter tubes spaced with a pitch-to-diameter ratio of 1.25. The heat exchanger is tested with waterflow on the shellside to determine a critical threshold, above which a small increase in the flowrate initiates a fluidelastic instability resulting in large amplitude vibration. The test conditions, the critical flowrates, the vibration frequencies, and the locations of the tubes most susceptible to vibration are presented. The given data are used for a comparison with a presently recognized method of vibration prediction and will permit updated evaluations as more advanced methods become available in the future.

  2. Observed Minimum Illuminance Threshold for Night Market Vendors in Kenya who use LED Lamps

    SciTech Connect (OSTI)

    Johnstone, Peter; Jacobson, Arne; Mills, Evan; Radecsky, Kristen

    2009-03-21T23:59:59.000Z

    Creation of light for work, socializing, and general illumination is a fundamental application of technology around the world. For those who lack access to electricity, an emerging and diverse range of LED based lighting products hold promise for replacing and/or augmenting their current fuel-based lighting sources that are costly and dirty. Along with analysis of environmental factors, economic models for total cost-ofownership of LED lighting products are an important tool for studying the impacts of these products as they emerge in markets of developing countries. One important metric in those models is the minimum illuminance demanded by end-users for a given task before recharging the lamp or replacing batteries. It impacts the lighting service cost per unit time if charging is done with purchased electricity, batteries, or charging services. The concept is illustrated in figure 1: LED lighting products are generally brightest immediately after the battery is charged or replaced and the illuminance degrades as the battery is discharged. When a minimum threshold level of illuminance is reached, the operational time for the battery charge cycle is over. The cost to recharge depends on the method utilized; these include charging at a shop at a fixed price per charge, charging on personal grid connections, using solar chargers, and purchasing dry cell batteries. This Research Note reports on the observed"charge-triggering" illuminance level threshold for night market vendors who use LED lighting products to provide general and task oriented illumination. All the study participants charged with AC power, either at a fixed-price charge shop or with electricity at their home.

  3. An Improved Lagrangian Relaxation Method for VLSI Combinational Circuit Optimization

    E-Print Network [OSTI]

    Huang, Yi-Le

    2012-02-14T23:59:59.000Z

    Gate sizing and threshold voltage (Vt) assignment are very popular and useful techniques in current very large scale integration (VLSI) design flow for timing and power optimization. Lagrangian relaxation (LR) is a common method for handling multi...

  4. Hydrodynamic sweepout thresholds in BWR Mark III reactor cavity interactions

    SciTech Connect (OSTI)

    Spencer, B.W.; Baronowsky, S.P.; Kilsdonk, D.J.

    1984-04-01T23:59:59.000Z

    Simulant-material experiments and related analysis are described which investigated hydrodynamics aspects of ex-vessel interactions following postulated core meltdown with subsequent meltthrough of the vessel lower head and ejection of molten corium from the vessel into the containment region beneath the vessel. Objectives were to examine the possible sweepout of water and corium from the cavity by the steam/H/sub 2/ flow. The dispersal pathways in this containment design include a single manway and four CRD penetrations in the cylindrical pedestal wall connecting to the drywell with a combined cross-sectional area of approx. 10 m/sup 2/. These openings range from 3.4 to 6.3 m in elevation off the concrete floor of the cavity. The experiments were performed using a 1:34 scale mock-up of the RPV/pedestal region. The first tests were quasi-steady tests. Tests were also performed using molten Wood's metal (WM). Some tests were performed with water on the cavity floor, and one test was performed using steel shot. The test results indicated that threshold gas flowrates existed beyond which dispersal of water and/or corium from the cavity can be expected. The predominant dispersal flow regime observed in the experiments involved fluidization of the water or molten WM by the gas flowrate through the system and sweepout of the fluidized liquid droplets as the gas exited the cavity through the openings in the wall. The superficial gas velocity at the onset of water sweepout ranged from 0.87 to 1.04 m/s in the tests which agrees very closely to the calculated fluidization threshold of 0.96 m/s. Application of the fluidization model for prediction of sweepout for the full-size system suggests that sweepout of water and corium can occur if the breach size in the RPV lower head exceeds approx. 10 and 17 cm dia, respectively, for steam blowdown at a vessel initial pressure of 1000 psi.

  5. An extremely sharp phase transition threshold for the slow growing hierarchy

    E-Print Network [OSTI]

    Weiermann, Andreas

    threshold point'. An everyday life example of this is the change from one material state to a different oneAn extremely sharp phase transition threshold for the slow growing hierarchy Andreas Weiermann of. This article is part of our general research program on phase transitions in logic

  6. Design and implementation of a sub-threshold wireless BFSK transmitter

    E-Print Network [OSTI]

    Paul, Suganth

    2009-05-15T23:59:59.000Z

    signal. We design and fabricate a sub-threshold wireless BFSK transmitter chip. The transmitter is specified to transmit baseband signals up to a data rate of 32kbps over a distance of 1000m. In addition to the sub-threshold implementation, we implement...

  7. Design and implementation of a sub-threshold wireless BFSK transmitter

    E-Print Network [OSTI]

    Paul, Suganth

    2008-10-10T23:59:59.000Z

    signal. We design and fabricate a sub-threshold wireless BFSK transmitter chip. The transmitter is specified to transmit baseband signals up to a data rate of 32kbps over a distance of 1000m. In addition to the sub-threshold implementation, we implement...

  8. Lake-level changes in central Patagonia (Argentina): crossing environmental thresholds

    E-Print Network [OSTI]

    Gilli, Adrian

    Lake-level changes in central Patagonia (Argentina): crossing environmental thresholds, Argentina 5 CONICET/Universidad Nacional de la Patagonia Austral, Ri´o Gallegos, Santa Cruz, Argentina-level changes in central Patagonia (Argentina): crossing environmental thresholds for Lateglacial and Holocene

  9. UNCORRECTEDPROOF 1 Fecundity determines the extinction threshold in a Canadian assemblage

    E-Print Network [OSTI]

    Holland, Jeffrey

    suggested to have negative effects on forest species. We determined 13 the extinction threshold for 12, species caught moving outside forest habitat had lower extinction thresholds than 19 species not caught habitat loss affects the 39extinction risk of different species is therefore an 40important part

  10. Transition state vibrational level thresholds for the dissociation of triplet ketene

    E-Print Network [OSTI]

    Kim, Sang Kyu

    Transition state vibrational level thresholds for the dissociation of triplet ketene Sang Kyu Kim of a unimolecular reaction is controlled by flux through quantized transition-state thresholds at each energy level­Ramsperger­Kassel­Marcus RRKM theory. The vibrational frequencies at the transition state obtained from the fits are compared

  11. Ultra Low Power 2-tier 3D Stacked Sub-threshold H.264 Intra Frame Encoder

    E-Print Network [OSTI]

    Lim, Sung Kyu

    longer battery life and do not demand a fast frequency of operation. Sub-threshold cir- cuits beneficial to such unattended sensor networks by extending their battery life. Sub- threshold design helps us in-house tools to handle TSVs and 3D stacking. The standard cells were sized with Cadence Virtuoso

  12. A New Technique To Determine The Upper Threshold for Finite Length Turbo Codes

    E-Print Network [OSTI]

    Chaturvedi, A K

    A New Technique To Determine The Upper Threshold for Finite Length Turbo Codes A.Rajeshand A in finite frame length turbo codes. These thresholds depend on the component encoder as well as the frame to indecisive and unequivocal fixed points respectively, for finiteframe length turbo codes. Concurrently, Gamal

  13. In vivo transcranial cavitation threshold detection during ultrasound-induced bloodbrain barrier opening in mice

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    In vivo transcranial cavitation threshold detection during ultrasound-induced blood­brain barrier cavitation threshold detection during ultrasound-induced blood­brain barrier opening in mice Yao-Sheng Tung1 cavitation response associated with blood­brain barrier (BBB) opening as induced by transcranial focused

  14. IEEE TRANSACTIONS ON DEPENDABLE AND SECURE COMPUTING 1 Epidemic Thresholds in Real Networks

    E-Print Network [OSTI]

    with viral spread exacerbates the problem [23]. The magnitude of viral propagation means that DDoS attacks at an exponential rate. Our epidemic threshold model subsumes many known thresholds for special-case graphs (e detrimental. With the exception of a few specialized modeling studies [18], [19], [28], [31], [34], much still

  15. High-energy above-threshold detachment from negative ions

    SciTech Connect (OSTI)

    Gazibegovic-Busuladzic, A.; Milosevic, D.B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Becker, W. [Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany)

    2004-11-01T23:59:59.000Z

    Above-threshold detachment of electrons from negative ions by an elliptically polarized laser field is analyzed within the strong-field approximation. The low-energy part of the spectrum, that is, its structure and its apparent cutoff, strongly depends on the orbital quantum number l of the initial ground state. The high-energy part is characterized by the usual extended plateau caused by rescattering, which is essentially independent of the ground state. The potential that the returning electron experiences during rescattering is modeled by the sum of a polarization potential and a static potential. This rescattering potential does not have much effect on the shape of the plateau, but it does on its height. For H{sup -} (l=0), the yield of rescattered electrons is five orders of magnitude below the direct electrons, while for I{sup -} (l=1) the yields only differ by a factor of 40. We also analyze the dependence of the angle-resolved energy spectrum on the ellipticity of the laser field and confirm general symmetry properties. An angle-integrated elliptic dichroism parameter is introduced and analyzed.

  16. Photoproduction of $?(1520)$ hyperons from nuclei near the threshold

    E-Print Network [OSTI]

    E. Ya. Paryev

    2011-12-01T23:59:59.000Z

    We present a theoretical investigation of $\\Lambda(1520)$ attenuation in ${\\gamma}A$ reactions near the threshold. It is performed in the framework of a collision model based on the nuclear spectral function. The model accounts for both primary photon-nucleon ${\\gamma}N \\to K\\Lambda(1520)$ and secondary pion-nucleon ${\\pi}N \\to K\\Lambda(1520)$ production processes. We calculate the target mass and momentum dependences of the forward $\\Lambda(1520)$ hyperon production from nuclei at photon energy of 2 GeV as well as for two options for its in-medium width. We find that the considered dependences are markedly sensitive to this width. Our studies also demonstrate that the secondary channel ${\\pi}N \\to K\\Lambda(1520)$ plays a substantial role in the intermediate momentum $\\Lambda(1520)$ photoproduction on nuclei in the chosen kinematics and, hence, is to be taken into account in the analysis of $\\Lambda(1520)$ hyperon photoproduction from nuclei with the aim to get information on its width in the matter.

  17. The sharp threshold for bootstrap percolation in all dimensions

    E-Print Network [OSTI]

    József Balogh; Béla Bollobás; Hugo Duminil-Copin; Robert Morris

    2011-02-24T23:59:59.000Z

    In r-neighbour bootstrap percolation on a graph G, a (typically random) set A of initially 'infected' vertices spreads by infecting (at each time step) vertices with at least r already-infected neighbours. This process may be viewed as a monotone version of the Glauber dynamics of the Ising model, and has been extensively studied on the d-dimensional grid $[n]^d$. The elements of the set A are usually chosen independently, with some density p, and the main question is to determine $p_c([n]^d,r)$, the density at which percolation (infection of the entire vertex set) becomes likely. In this paper we prove, for every pair $d \\ge r \\ge 2$, that there is a constant L(d,r) such that $p_c([n]^d,r) = [(L(d,r) + o(1)) / log_(r-1) (n)]^{d-r+1}$ as $n \\to \\infty$, where $log_r$ denotes an r-times iterated logarithm. We thus prove the existence of a sharp threshold for percolation in any (fixed) number of dimensions. Moreover, we determine L(d,r) for every pair (d,r).

  18. aerogel threshold cherenkov: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    by a significant noise suppression capability of the method using simple low-pass filters in the image frequency domain. The FT-method allows very deep tail' (and...

  19. SU-D-9A-02: Relative Effects of Threshold Choice and Spatial Resolution Modeling On SUV and Volume Quantification in F18-FDG PET Imaging of Anal Cancer Patients

    SciTech Connect (OSTI)

    Zhao, F [Duke University Medical Center, Durham, NC (United States); Shandong Cancer Hospital and Insititute, Jinan, Shandong (China); Bowsher, J; Palta, M; Czito, B; Willett, C; Yin, F [Duke University Medical Center, Durham, NC (United States)

    2014-06-01T23:59:59.000Z

    Purpose: PET imaging with F18-FDG is utilized for treatment planning, treatment assessment, and prognosis. A region of interest (ROI) encompassing the tumor may be determined on the PET image, often by a threshold T on the PET standard uptake values (SUVs). Several studies have shown prognostic value for relevant ROI properties including maximum SUV value (SUVmax), metabolic tumor volume (MTV), and total glycolytic activity (TGA). The choice of threshold T may affect mean SUV value (SUVmean), MTV, and TGA. Recently spatial resolution modeling (SRM) has been introduced on many PET systems. SRM may also affect these ROI properties. The purpose of this work is to investigate the relative influence of SRM and threshold choice T on SUVmean, MTV, TGA, and SUVmax. Methods: For 9 anal cancer patients, 18F-FDG PET scans were performed prior to treatment. PET images were reconstructed by 2 iterations of Ordered Subsets Expectation Maximization (OSEM), with and without SRM. ROI contours were generated by 5 different SUV threshold values T: 2.5, 3.0, 30%, 40%, and 50% of SUVmax. Paired-samples t tests were used to compare SUVmean, MTV, and TGA (a) for SRM on versus off and (b) between each pair of threshold values T. SUVmax was also compared for SRM on versus off. Results: For almost all (57/60) comparisons of 2 different threshold values, SUVmean, MTV, and TGA showed statistically significant variation. For comparison of SRM on versus off, there were no statistically significant changes in SUVmax and TGA, but there were statistically significant changes in MTV for T=2.5 and T=3.0 and in SUVmean for all T. Conclusion: The near-universal statistical significance of threshold choice T suggests that, regarding harmonization across sites, threshold choice may be a greater concern than choice of SRM. However, broader study is warranted, e.g. other iterations of OSEM should be considered.

  20. Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices

    DOE Patents [OSTI]

    Chassin, David P. (Pasco, WA); Donnelly, Matthew K. (Kennewick, WA); Dagle, Jeffery E. (Richland, WA)

    2011-12-06T23:59:59.000Z

    Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

  1. Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices

    DOE Patents [OSTI]

    Chassin, David P. (Pasco, WA); Donnelly, Matthew K. (Kennewick, WA); Dagle, Jeffery E. (Richland, WA)

    2006-12-12T23:59:59.000Z

    Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

  2. A factorization approach to next-to-leading-power threshold logarithms

    E-Print Network [OSTI]

    D. Bonocore; E. Laenen; L. Magnea; S. Melville; L. Vernazza; C. D. White

    2015-05-29T23:59:59.000Z

    Threshold logarithms become dominant in partonic cross sections when the selected final state forces gluon radiation to be soft or collinear. Such radiation factorizes at the level of scattering amplitudes, and this leads to the resummation of threshold logarithms which appear at leading power in the threshold variable. In this paper, we consider the extension of this factorization to include effects suppressed by a single power of the threshold variable. Building upon the Low-Burnett-Kroll-Del Duca (LBKD) theorem, we propose a decomposition of radiative amplitudes into universal building blocks, which contain all effects ultimately responsible for next-to-leading power (NLP) threshold logarithms in hadronic cross sections for electroweak annihilation processes. In particular, we provide a NLO evaluation of the "radiative jet function", responsible for the interference of next-to-soft and collinear effects in these cross sections. As a test, using our expression for the amplitude, we reproduce all abelian-like NLP threshold logarithms in the NNLO Drell-Yan cross section, including the interplay of real and virtual emissions. Our results are a significant step towards developing a generally applicable resummation formalism for NLP threshold effects, and illustrate the breakdown of next-to-soft theorems for gauge theory amplitudes at loop level.

  3. Low-energy-threshold analysis of the Phase I and Phase II data sets of the Sudbury Neutrino Observatory

    E-Print Network [OSTI]

    Monroe, Jocelyn

    Results are reported from a joint analysis of Phase I and Phase II data from the Sudbury Neutrino Observatory. The effective electron kinetic energy threshold used is Teff=3.5 MeV, the lowest analysis threshold yet achieved ...

  4. DESIGN CONSIDERATIONS ON PEAK POWER CLIPPING THRESHOLDS IN MICROGRIDS

    E-Print Network [OSTI]

    Paderborn, Universität

    the utility grid. This kind of operating strategy is called e.g. "peak load shaving", "peak power reduction. This method is broadly applicable to similar applications, e.g. for peak-shaving of PV power to limit" or just "peak shaving" and is applied to diverse applications and systems. This paper presents a method

  5. Measurement Of Transverse Instability Thresholds In Low And high Emittance optics At The Photon Factory Storage Ring

    E-Print Network [OSTI]

    Sakanaka, S; Kamiya, Yu; Katoh, M; Kobayakawa, H

    1990-01-01T23:59:59.000Z

    Measurement Of Transverse Instability Thresholds In Low And high Emittance optics At The Photon Factory Storage Ring

  6. An Excitatory Loop with Astrocytes Contributes to Drive Neurons to Seizure Threshold

    E-Print Network [OSTI]

    Newman, Eric A.

    An Excitatory Loop with Astrocytes Contributes to Drive Neurons to Seizure Threshold Marta Go´ mez to control seizures. Citation: Go´mez-Gonzalo M, Losi G, Chiavegato A, Zonta M, Cammarota M, et al. (2010

  7. Long-Range Validity of Threshold Laws in Inner-Shell Photodetachment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the ALS, and Denison University has now shown that the threshold laws for inner-shell photodetachment of negative ions are not only obeyed but can extend over a much...

  8. $pp\\to pp?^0$ near threshold in pionless effective field theory

    E-Print Network [OSTI]

    Shung-ichi Ando

    2007-08-30T23:59:59.000Z

    In this talk, we review our recent calculation for the $pp\\to pp\\pi^0$ reaction near threshold in pionless effective field theory with a di-baryon and external pions.

  9. Increased Resilience in Threshold Cryptography Sharing a Secret with Devices That Cannot Store Shares

    E-Print Network [OSTI]

    -mail, authorise bank transactions or access social network sites. As a consequence, personal devices are used more of battery power. These weaknesses can be mitigated by introducing threshold cryptography. The aim

  10. Intensity-resolved Above Threshold Ionization Yields of Atoms with Ultrashort Laser Pulses

    E-Print Network [OSTI]

    Hart, Nathan Andrew

    2012-10-19T23:59:59.000Z

    The above threshold ionization (ATI) spectra provide a diversity of information about a laser-atom ionization process such as laser intensity, pulse duration, carrier envelope phase, and atomic energy level spacing. However, the spatial distribution...

  11. Soft pneumatic artificial muscles with low threshold pressures for a cardiac compression device

    E-Print Network [OSTI]

    Obiajulu, Steven (Steven C.)

    2013-01-01T23:59:59.000Z

    In this paper, I present the design, fabrication and characterization of fully soft pneumatic artificial muscles (PAMs) with low threshold pressures that are intended for direct cardiac compression (DCC). McKibben type ...

  12. Hair cell regeneration and recovery of auditory thresholds following aminoglycoside ototoxicity in Bengalese nches

    E-Print Network [OSTI]

    Rubel, Edwin

    Hair cell regeneration and recovery of auditory thresholds following aminoglycoside ototoxicity Birds regenerate auditory hair cells when original hair cells are lost. Regenerated hair cells become innervated and restore hearing function. Functional recovery during hair cell regeneration is particularly

  13. Quantum probabilities and violation of CHSH-inequality from classical random signals and threshold type properly calibrated detectors

    E-Print Network [OSTI]

    Andrei Khrennikov

    2011-12-03T23:59:59.000Z

    We present a purely wave model (based on classical random field) which reproduces quantum probabilities (given by the fundamental law of quantum mechanics, Born's rule) including probabilities for joint detection of a pair of quantum observables (e.g., spin or polarization projections). The crucial point of our approach is that the presence of detector's threshold and calibration procedure have to be treated not as simply experimental technicalities, but as the basic counteparts of the theoretical model. The presence of the background field (vacuum fluctuations) is also the key-element of our prequantum model. It is of the classical signal type and the methods of classical signal theory (including statistical radiophysics) are used for its development. We stress that our prequantum model is not objective, i.e., the values of observables (clicks of detectors) cannot be assigned in advance, i.e., before measurement. Hence, the dilemma, nonobjectivity or nonlocality, is resolved in favor of nonobjectivity (our model is local of the classical field type). In particular, we reproduce the probabilities for the EPR-experiment for photon polarization and, hence, violate CHSH inequality for classical random signals (measured by the threshold type and properly calibrated detectors acting in the presence of the background field).

  14. Comparison of the "method of limits" and "alternate choice" methods in vibrometry testing

    E-Print Network [OSTI]

    Hayes, Eloise Carlton

    1992-01-01T23:59:59.000Z

    are the "method of limits" and "alternate choice" techniques. This investigation evaluated and compared these two techniques. The primary purpose of this investigation was to determine if these testing methods obtain the same vibration threshold... and to invesugate the relationship between the methods. The methods were used to test male and female populations for their vibration sensitivity in the median nerve (index finger) and the ulnar nerve (little finger) of both hands. This study utilized...

  15. Influence of the backward propagating waves on the threshold in planar nematic liquid crystal films

    E-Print Network [OSTI]

    Dmitry O. Krimer; Andrey E. Miroshnichenko; Etienne Brasselet

    2010-10-19T23:59:59.000Z

    We analyze theoretically the influence of backward propagating waves on the primary threshold when a linearly polarized light impinges at normal incidence on a planarly aligned nematic liquid crystal films. We show, that the primary threshold, as a function of the phase delay induced by the nematic layer, exhibits oscillations. The amplitude of oscillations depends strongly on the drop of the refractivity indices of the nematic and outer media at the boundaries.

  16. An analysis of the threshold necessary to sustain rural Texas retail outlets

    E-Print Network [OSTI]

    Adcock, Donna P

    1992-01-01T23:59:59.000Z

    AN ANALYSIS OF THE THRESHOLD NECESSARY TO SUSTAIN RURAL TEXAS RETAIL OUTLETS A Thesis by DONNA PFLUGER ADCOCK Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1992 Major Subject: Agricultural Economics AN ANALYSIS OF THE THRESHOLD NECESSARY TO SUSTAIN RURAL TEXAS RETAIL OUTLETS A Thesis by DONNA PFLUGER ADCOCK Approved as to style and content by: Dennis U. Fisher (Chair...

  17. Supporting Online Material Materials and Methods

    E-Print Network [OSTI]

    Wolfe, Cecily J.

    1 Supporting Online Material Materials and Methods (15) For all possible earthquake pairs. The parameters chosen for window length, filter bandpass, negative sidelobe identification, and cross-correlation threshold are appropriate for high-frequency earthquakes. In order to remove false positives or poor data

  18. Optical breakdown threshold investigation of 1064 nm laser induced air plasmas

    SciTech Connect (OSTI)

    Thiyagarajan, Magesh; Thompson, Shane [Plasma Engineering Research Lab (PERL), College of Science and Engineering, Texas A and M University-Corpus Christi, Texas 78412 (United States)

    2012-04-01T23:59:59.000Z

    We present the theoretical and experimental measurements and analysis of the optical breakdown threshold for dry air by 1064 nm infrared laser radiation and the significance of the multiphoton and collisional cascade ionization process on the breakdown threshold measurements over pressures range from 10 to 2000 Torr. Theoretical estimates of the breakdown threshold laser intensities and electric fields are obtained using two distinct theories namely multiphoton and collisional cascade ionization theories. The theoretical estimates are validated by experimental measurements and analysis of laser induced breakdown processes in dry air at a wavelength of 1064 nm by focusing 450 mJ max, 6 ns, 75 MW max high-power 1064 nm IR laser radiation onto a 20 {mu}m radius spot size that produces laser intensities up to 3 - 6 TW/cm{sup 2}, sufficient for air ionization over the pressures of interest ranging from 10 to 2000 Torr. Analysis of the measured breakdown threshold laser intensities and electric fields are carried out in relation with classical and quantum theoretical ionization processes, operating pressures. Comparative analysis of the laser air breakdown results at 1064 nm with corresponding results of a shorter laser wavelength (193 nm) [M. Thiyagarajan and J. E. Scharer, IEEE Trans. Plasma Sci. 36, 2512 (2008)] and a longer microwave wavelength (10{sup 8} nm) [A. D. MacDonald, Microwave Breakdown in Gases (Wiley, New York, 1966)]. A universal scaling analysis of the breakdown threshold measurements provided a direct comparison of breakdown threshold values over a wide range of frequencies ranging from microwave to ultraviolet frequencies. Comparison of 1064 nm laser induced effective field intensities for air breakdown measurements with data calculated based on the collisional cascade and multiphoton breakdown theories is used successfully to determine the scaled collisional microwave portion. The measured breakdown threshold of 1064 nm laser intensities are then scaled to classical microwave breakdown theory after correcting for the multiphoton ionization process for different pressures and good agreement, regarding both pressure dependence and breakdown threshold electric fields, is obtained. The effect of the presence of submicron particles on the 1064 nm breakdown threshold was also investigated. The measurements show that higher breakdown field is required, especially at lower pressures, and in close agreement with classical microwave breakdown theory and measurements in air.

  19. THRESHOLD PROBABILITY FUNCTIONS AND THERMAL INHOMOGENEITIES IN THE Ly{alpha} FOREST

    SciTech Connect (OSTI)

    Lee, Khee-Gan; Spergel, David N., E-mail: lee@astro.princeton.edu, E-mail: dns@astro.princeton.edu [Department of Astrophysical Science, Princeton University, Princeton, NJ 08544 (United States)

    2011-06-10T23:59:59.000Z

    We introduce to astrophysics the threshold probability functions S{sub 2}, C{sub 2}, and D{sub 2} first derived by Torquato et al., which effectively samples the flux probability distribution function (PDF) of the Ly{alpha} forest at different spatial scales. These statistics are tested on mock Ly{alpha} forest spectra based on various toy models for He II reionization, with homogeneous models with various temperature-density relations as well as models with temperature inhomogeneities. These mock samples have systematics and noise added to simulate the latest Sloan Digital Sky Survey Data Release 7 (SDSS DR7) data. We find that the flux PDF from SDSS DR7 can be used to constrain the temperature-density relation {gamma} (where T{proportional_to}(1 + {Delta}){sup {gamma}-1}) of the intergalactic medium (IGM) at z = 2.5 to a precision of {Delta}{gamma} = 0.2 at {approx}4{sigma} confidence. The flux PDF is degenerate to temperature inhomogeneities in the IGM arising from He II reionization, but we find S{sub 2} can detect these inhomogeneities at {approx}3{sigma}, with the assumption that the flux continuum of the Ly{alpha} forest can be determined to 9% accuracy, approximately the error from current fitting methods. If the flux continuum can be determined to 3% accuracy, then S{sub 2} is capable of constraining the characteristic scale of temperature inhomogeneities, with {approx}4{sigma} differentiation between toy models with hot bubble radii of 50 h{sup -1} Mpc and 25 h{sup -1} Mpc.

  20. Threshold velocity for environmentally-assisted cracking in low alloy steels

    SciTech Connect (OSTI)

    Wire, G.L.; Kandra, J.T.

    1997-04-01T23:59:59.000Z

    Environmentally Assisted Cracking (EAC) in low alloy steels is generally believed to be activated by dissolution of MnS inclusions at the crack tip in high temperature LWR environments. EAC is the increase of fatigue crack growth rate of up to 40 to 100 times the rate in air that occurs in high temperature LWR environments. A steady state theory developed by Combrade, suggested that EAC will initiate only above a critical crack velocity and cease below this same velocity. A range of about twenty in critical crack tip velocities was invoked by Combrade, et al., to describe data available at that time. This range was attributed to exposure of additional sulfides above and below the crack plane. However, direct measurements of exposed sulfide densities on cracked specimens were performed herein and the results rule out significant additional sulfide exposure as a plausible explanation. Alternatively, it is proposed herein that localized EAC starting at large sulfide clusters reduces the calculated threshold velocity from the value predicted for a uniform distribution of sulfides. Calculations are compared with experimental results where the threshold velocity has been measured, and the predicted wide range of threshold values for steels of similar sulfur content but varying sulfide morphology is observed. The threshold velocity decreases with the increasing maximum sulfide particle size, qualitatively consistent with the theory. The calculation provides a basis for a conservative minimum velocity threshold tied directly to the steel sulfur level, in cases where no details of sulfide distribution are known.

  1. Estimating Alarm Thresholds for Process Monitoring Data under Different Assumptions about the Data Generating Mechanism

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Burr, Tom; Hamada, Michael S.; Howell, John; Skurikhin, Misha; Ticknor, Larry; Weaver, Brian

    2013-01-01T23:59:59.000Z

    Process monitoring (PM) for nuclear safeguards sometimes requires estimation of thresholds corresponding to small false alarm rates. Threshold estimation dates to the 1920s with the Shewhart control chart; however, because possible new roles for PM are being evaluated in nuclear safeguards, it is timely to consider modern model selection options in the context of threshold estimation. One of the possible new PM roles involves PM residuals, where a residual is defined as residual = data ? prediction. This paper reviews alarm threshold estimation, introduces model selection options, and considers a range of assumptions regarding the data-generating mechanism for PM residuals.more »Two PM examples from nuclear safeguards are included to motivate the need for alarm threshold estimation. The first example involves mixtures of probability distributions that arise in solution monitoring, which is a common type of PM. The second example involves periodic partial cleanout of in-process inventory, leading to challenging structure in the time series of PM residuals.« less

  2. Ultra-low threshold, electrically pumped quantum dot photonic crystal nanocavity laser

    E-Print Network [OSTI]

    Bryan Ellis; Marie Mayer; Gary Shambat; Tomas Sarmiento; James Harris; Eugene Haller; Jelena Vuckovic

    2011-05-02T23:59:59.000Z

    Efficient, low threshold, and compact semiconductor laser sources are being investigated for many applications in high-speed communications, information processing, and optical interconnects. The best edge-emitting and vertical cavity surface-emitting lasers (VCSELs) have thresholds on the order of 100 \\muA[1,2] but dissipate too much power to be practical for many applications, particularly optical interconnects[3]. Optically pumped photonic crystal (PC) nanocavity lasers represent the state of the art in low-threshold lasers[4,5]; however, in order to be practical, techniques to electrically pump these structures must be developed. Here we demonstrate a quantum dot photonic crystal nanocavity laser in gallium arsenide pumped by a lateral p-i-n junction formed by ion implantation. Continuous wave lasing is observed at temperatures up to 150 K. Thresholds of only 181 nA at 50 K and 287 nA at 150 K are observed - the lowest thresholds ever observed in any type of electrically pumped laser.

  3. Threshold law for electron impact ionization in the model of Temkin and Poet

    SciTech Connect (OSTI)

    Macek, J.H. [Univ. of Tennessee, Knoxville, TN (United States)

    1996-05-01T23:59:59.000Z

    The angle-Sturmian theory is used to derive the threshold law for ionization of atomic hydrogen by electron impact in the model of Temkin and Poet. In this model, the exact electron-electron interaction is replaced by its monopole term. As for Wannier`s theory with the real interaction, ionization occurs only for electrons that start out nearly equidistant from the proton. Because there is a high propensity for one electron to be captured into a bound state, ionization is strongly suppressed, giving rise to a threshold law of the form {sigma} {proportional_to} exp[{minus}aE{sup {minus}1/6} + bE{sup 1/6}], where a and b are constants. The exponential law appears to be the quantal counterpart of the classical offset of the ionization threshold. Relative energy distribution are computed and found to favor configurations with unequal energy sharing.

  4. Adapting to a Changing Environment: Non-obvious Thresholds in Multi-Scale Systems

    E-Print Network [OSTI]

    Clare Perryman; Sebastian Wieczorek

    2014-07-09T23:59:59.000Z

    Many natural and technological systems fail to adapt to changing external conditions and move to a different state if the conditions vary too fast. Such "non-adiabatic" processes are ubiquitous, but little understood. We identify these processes with a new nonlinear phenomenon---an intricate threshold where a forced system fails to adiabatically follow a changing stable state. In systems with multiple time-scales such thresholds are generic, but non-obvious, meaning they cannot be captured by traditional stability theory. Rather, the phenomenon can be analysed using concepts from modern singular perturbation theory: folded singularities and canard trajectories, including composite canards. Thus, non-obvious thresholds should explain the failure to adapt to a changing environment in a wide range of multi-scale systems including: tipping points in the climate system, regime shifts in ecosystems, excitability in nerve cells, adaptation failure in regulatory genes, and adiabatic switching in technology.

  5. Threshold effects on renormalization group running of neutrino parameters in the low-scale seesaw model

    E-Print Network [OSTI]

    Johannes Bergstrom; Tommy Ohlsson; He Zhang

    2011-04-04T23:59:59.000Z

    We show that, in the low-scale type-I seesaw model, renormalization group running of neutrino parameters may lead to significant modifications of the leptonic mixing angles in view of so-called seesaw threshold effects. Especially, we derive analytical formulas for radiative corrections to neutrino parameters in crossing the different seesaw thresholds, and show that there may exist enhancement factors efficiently boosting the renormalization group running of the leptonic mixing angles. We find that, as a result of the seesaw threshold corrections to the leptonic mixing angles, various flavor symmetric mixing patterns (e.g., bi-maximal and tri-bimaximal mixing patterns) can be easily accommodated at relatively low energy scales, which is well within the reach of running and forthcoming experiments (e.g., the LHC).

  6. First passage times in integrate-and-fire neurons with stochastic thresholds

    E-Print Network [OSTI]

    Braun, Wilhelm; Thul, Rüdiger

    2015-01-01T23:59:59.000Z

    We consider a leaky integrate--and--fire neuron with deterministic subthreshold dynamics and a firing threshold that evolves as an Ornstein-Uhlenbeck process. The formulation of this minimal model is motivated by the experimentally observed widespread variation of neural firing thresholds. We show numerically that the mean first passage time can depend non-monotonically on the noise amplitude. For sufficiently large values of the correlation time of the stochastic threshold the mean first passage time is maximal for non-vanishing noise. We provide an explanation for this effect by analytically transforming the original model into a first passage time problem for Brownian motion. This transformation also allows for a perturbative calculation of the first passage time histograms. In turn this provides quantitative insights into the mechanisms that lead to the non-monotonic behaviour of the mean first passage time. The perturbation expansion is in excellent agreement with direct numerical simulations. The approa...

  7. Temperature dependence of the threshold current for InGaAlP visible laser diodes

    SciTech Connect (OSTI)

    Ishikawa, M.; Shiozawa, H.; Itaya, K.; Hatakoshi, G.; Uematsu, Y. (Research and Development Center, Toshiba Corp., Saiwai-ku, Kawasaki 210 (JP))

    1991-01-01T23:59:59.000Z

    The temperature dependence of the threshold current for InGaAlP visible light laser diodes is investigated from the aspect of gain-current characteristics. The cavity length dependence of light output power versus current characteristic was evaluated for a 40 {mu}m width InGaP-InBaAlP broad-stripe laser in the temperature range between {minus} 70 and 90{degrees} C, which had about a 670 nm oscillation wavelength at room temperature. The threshold-current density dependence on the cavity length shows that a linear-gain approximation is suitable for this system. A minimum threshold-current density at 860 A/cm{sup 2} was achieved at room temperature with a cavity length of 1160 {mu}m, which is the lowest value ever reported for this material. The linear-gain parameters {beta} and {ital J}{sub 0} depended on the temperature with the characteristic temperature of about 200 K, which is considered to be the intrinsic characteristic temperature of the threshold current for this active-layer material. The internal quantum efficiency, derived from the cavity length dependence of the differential quantum efficiency, decreased in the temperature range higher than {minus}10{degrees} C, which affected the excess threshold-current increase and the decrease in the characteristic temperature at this temperature range. The theoretical calculation, considering a one-dimensional band structure model, showed that this excess increase of the threshold current was found to be attributed to the electron overflow current into the p-type cladding layer.

  8. Threshold law for the triplet state for electron-impact ionization in the Temkin-Poet model

    SciTech Connect (OSTI)

    Ihra, W.; Mota-Furtado, F.; OMahony, P.F. [Department of Mathematics, Royal Holloway, University of London, Egham, Surrey TW200EX (United Kingdom)] [Department of Mathematics, Royal Holloway, University of London, Egham, Surrey TW200EX (United Kingdom); Macek, J.H. [Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1501 (United States)] [Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1501 (United States); [Oak Ridge National Laboratory, Post Office Box 2009 Oak Ridge, Tennessee 37831 (United States)

    1997-04-01T23:59:59.000Z

    We derive the analytical threshold behavior for the triplet cross section for electron-impact ionization in the Temkin-Poet model. The analytical results indicate that the most recent numerical calculations may fail to reproduce the correct threshold behavior in an energy regime below about E=0.1 a.u. We also present an analytical expression for the energy distribution of the two electrons near threshold. {copyright} {ital 1997} {ital The American Physical Society}

  9. Experimental study on GaP surface damage threshold induced by a high repetition rate femtosecond laser

    SciTech Connect (OSTI)

    Li Yi; Liu Feng; Li Yanfeng; Chai Lu; Xing Qirong; Hu Minglie; Wang Chingyue

    2011-05-01T23:59:59.000Z

    The surface damage threshold of undoped bulk <110> GaP induced by a high repetition rate femtosecond pulse at 1040 nm with a duration of 61 fs was studied. The threshold value was obtained by a linear fit of the incident single pulse fluence and was confirmed with a breakdown test around the threshold level. The result will be useful in high intensity, high repetition rate laser applications and ultrafast processes.

  10. Scaling laws and minimum threshold currents for quantum-confined semiconductor lasers

    SciTech Connect (OSTI)

    Yariv, A.

    1988-09-19T23:59:59.000Z

    Basic scaling laws are derived for bulk, two-dimensional (quantum well) and one-dimensional (quantum wire) semiconductor lasers. Starting from quantum derivation of the optical properties of confined carriers, the dimensional dependencies of the scaling laws are made explicit. Threshold currents of approx.100 and 2--3 ..mu..A are predicted for single quantum well and quantum wire lasers, respectively. The basic considerations of this analysis were used recently to obtain ultralow threshold quantum well lasers (P. L. Derry, A. Yariv, K. Lau, N. Bar-Chaim, K. Lee, and J. Rosenberg, Appl. Phys. Lett. 50, 1773 (1987)).

  11. Low threshold InGaAsP terrace mass transport laser on semi-insulating substrate

    SciTech Connect (OSTI)

    Chen, T.R.; Chiu, L.C.; Yu, K.L.; Koren, U.; Hasson, A.; Margalit, S.; Yariv, A.

    1982-12-15T23:59:59.000Z

    Very low threshold InGaAsP terrace lasers on semi-insulating (SI) InP substrate have been fabricated using the mass transport technique. The fabrication process involves a single-step liquid phase epitaxial (LPE) growth followed by a mass transport of InP at approx.675 /sup 0/C in the presence of an InP cover wafer. Lasers operating in the fundamental transverse mode with smooth far-field patterns and threshold currents as low as 9.5 mA have been obtained.

  12. Difference Thresholds for Timbre Related to Amplitude Spectra of Complex Sounds

    E-Print Network [OSTI]

    Kendall, Roger A.

    1975-01-01T23:59:59.000Z

    Final Investigation 121 11. Treatment x Subjects AN0VA: Data from Table 10 121 12. Scheffe Comparisons: Data from Table 11 123 13. Mean Upper and Lower Thresholds for Timbre 124 14. Treatment x Subjects AN0VA: Upper Threshold Data + from Table 13... can be represented as 360° along the time axis because of the mathematical relation between simple harmonic motion and circular functions. Thus the phase at any point during a cycle may vary between 0° and 360°. The phase angle or phase difference...

  13. Drell-Yan Production at Threshold to Third Order in QCD

    E-Print Network [OSTI]

    Taushif Ahmed; Maguni Mahakhud; Narayan Rana; V. Ravindran

    2014-12-11T23:59:59.000Z

    The recent computation on the full threshold contributions to Higgs boson production at next-to-next-to-next-to-leading order (N$^3$LO) in QCD contains valuable information on the soft gluons resulting from virtual and real emission partonic subprocesses. We use those from the real emissions to obtain the corresponding soft gluon contributions to Drell-Yan production and determine the missing $\\delta(1-z)$ part of the N$^3$LO. The numerical impact of threshold effects demonstrates the importance of our results in the precision study with the Drell-Yan process at the LHC.

  14. High Energy Thresholds in SUSY GUTs - A refined analysis

    E-Print Network [OSTI]

    A. Katsikatsou

    2014-11-26T23:59:59.000Z

    In a previous paper we have developed a novel method in order to parametrize the effect of the large number of HETs into as fewer parameters as possible. Apart from its obvious advantages this parametrization serves as a vehicle for the examination of the validity of a minimal SO(10) model concerning a series of constraints. Among them is demand for unification of the gauge couplings, the experimental values of the strong coupling constant and lower experimental bound of the proton lifetime. All of these claims lead to preferred regions both in the soft the superheavy parameter space. In this paper we give the necessary updates of our results which stem mainly from the recent experimental measurements. We also include some additions in our analysis involving the universal trilinear coupling A_0 and the rate x, which is related to superheavy vevs. Finally we cross-check the preferred regions of the parameter space and narrow the even more by applying new constraints based on the results of the LHC experiment for the mass of the Higgs particle and the supersymmetry exclusion limits.

  15. High Energy Thresholds in SUSY GUTs - A refined analysis

    E-Print Network [OSTI]

    Katsikatsou, A

    2014-01-01T23:59:59.000Z

    In a previous paper we have developed a novel method in order to parametrize the effect of the large number of HETs into as fewer parameters as possible. Apart from its obvious advantages this parametrization serves as a vehicle for the examination of the validity of a minimal SO(10) model concerning a series of constraints. Among them is demand for unification of the gauge couplings, the experimental values of the strong coupling constant and lower experimental bound of the proton lifetime. All of these claims lead to preferred regions both in the soft the superheavy parameter space. In this paper we give the necessary updates of our results which stem mainly from the recent experimental measurements. We also include some additions in our analysis involving the universal trilinear coupling A_0 and the rate x, which is related to superheavy vevs. Finally we cross-check the preferred regions of the parameter space and narrow the even more by applying new constraints based on the results of the LHC experiment f...

  16. Electron-Nuclear Energy Sharing in Above-Threshold Multiphoton Dissociative Ionization of H2

    E-Print Network [OSTI]

    Thumm, Uwe

    Electron-Nuclear Energy Sharing in Above-Threshold Multiphoton Dissociative Ionization of H2 J. Wu­4], where the photon energy is shared by the freed electrons and the nuclear fragments. For the molecular ionization [10­15], and the imaging of inter- nuclear distance using nuclear kinetic energy release spec- tra

  17. Effects of creatine loading on electromyographic fatigue threshold during cycle ergometry in college-aged women

    E-Print Network [OSTI]

    Smith, Abbie E.; Walter, Ashley A.; Herda, Trent J.; Ryan, Eric D.; Moon, Jordan R.; Cramer, Joel T.; Stout, Jeffrey R.

    2007-01-01T23:59:59.000Z

    The purpose of this study was to examine the effects of 5 days of Creatine (Cr) loading on the electromyographic fatigue threshold (EMGFT) in college-aged women. Fifteen healthy college-aged women (mean ± SD = 22.3 ± 1.7 yrs) volunteered...

  18. Dense granular ows: two-particle argument accounts for friction-like constitutive law with threshold

    E-Print Network [OSTI]

    Recanati, Catherine

    robust scaling behav- iors in various ow geomerties for dry grains, whether frictional or not [2, 4Dense granular ows: two-particle argument accounts for friction-like constitutive law a constitutive law that exhibits a ow threshold expressed as a #12;nite e#11;ective friction at ow onset

  19. Dense granular flows: two-particle argument accounts for friction-like constitutive law with threshold

    E-Print Network [OSTI]

    Boyer, Edmond

    Dense granular flows: two-particle argument accounts for friction-like constitutive law that exhibits a flow threshold expressed as a finite effective friction at flow onset. The value 83.10.Gr 83.60.La I. INTRODUCTION Dense flows of dry granular materials and granular pastes is still

  20. Determination of energy thresholds on an artificial retina using a multiple-pulsed laser 

    E-Print Network [OSTI]

    Stephenson, Albert David

    1999-01-01T23:59:59.000Z

    This study is focused on determining single and multiple pulse ED?? for laser pulses of 200 ns duration. Energy thresholds in this experiment were determined on an artificial retina, for a variety of pulse widths and spot sizes. Due to numerous...

  1. TQuEST: Threshold Query Execution for Large Sets of Time Series

    E-Print Network [OSTI]

    Kriegel, Hans-Peter

    TQuEST: Threshold Query Execution for Large Sets of Time Series Johannes AÃ?falg, Hans-Peter Kriegel TQuEST, a powerful query processor for time series databases. TQuEST supports a novel but very useful times. 1 Introduction In this paper, we present TQuEST, a powerful analysis tool for time series

  2. Perspective Aligand-receptor signaling threshold model of stem cell differentiation control

    E-Print Network [OSTI]

    Zandstra, Peter W.

    Perspective Aligand-receptor signaling threshold model of stem cell differentiation control and theoretical framework for pre- dicting and controlling the outcome of HSC stimulation by exogenous cytokines or by extracellular matrix- or cell-bound cyto- kine presentation. According to such a model, when the relevant ligand

  3. A threshold area ratio of organic to conventional agriculture causes recurrent pathogen outbreaks in organic agriculture

    E-Print Network [OSTI]

    Kolokolnikov, Theodore

    A threshold area ratio of organic to conventional agriculture causes recurrent pathogen outbreaks in organic agriculture S. Adl a, , D. Iron b , T. Kolokolnikov b a Department of Biology, Dalhousie Fungal spores Organic agriculture Pathogen dispersal Conventional agriculture uses herbicides, pesticides

  4. An Algorithm to Learn ReadOnce Threshold Formulas, and some Generic Transformations between Learning Models

    E-Print Network [OSTI]

    Eckmiller, Rolf

    An Algorithm to Learn Read­Once Threshold Formulas, and some Generic Transformations between@cpsc.ucalgary.ca Thomas R. Hancock y Siemens Corporate Research, Inc. 755 College Road East Princeton, NJ 08540 e­mail: hancock@learning.scr.siemens.com Lisa Hellerstein z Department of EECS Northwestern University 2145

  5. An Algorithm to Learn Read-Once Threshold Formulas, and some Generic Transformations between Learning Models

    E-Print Network [OSTI]

    Eckmiller, Rolf

    An Algorithm to Learn Read-Once Threshold Formulas, and some Generic Transformations between. Hancocky Siemens Corporate Research, Inc. 755 College Road East Princeton, NJ 08540 e-mail: hancock@learning.scr.siemens of generic transformations that can be used to convert an algorithm in one learning model into an algorithm

  6. Embedded epitaxial growth of low-threshold GaInAsP/InP injection lasers

    SciTech Connect (OSTI)

    Chen, P.C.; Yu, K.L.; Margalit, S.; Yariv, A.

    1981-03-01T23:59:59.000Z

    Single-growth liquid-phase embedded epitaxy in the GaInAsP/InP system is described, and a new heterostructure laser is grown using this technique. These lasers exhibit excellent current and optical confinement. Threshold currents as low as 45 mA are achieved for a laser with 4-..mu..m-wide active region.

  7. L-H Transition Threshold; Orbit Loss Theory Revisited J.A. Heikkinen1

    E-Print Network [OSTI]

    L-H Transition Threshold; Orbit Loss Theory Revisited J.A. Heikkinen1 , T.P. Kiviniemi2 , T. Kurki of different theoretical models to explain a transition to an H-mode in toroidal plasmas have been suggested [1]. Common to most of them is that a strong shear in ExB rotation is required at the transition conditions

  8. Adaptive Threshold Spike Detection using Stationary Wavelet Transform for Neural Recording Implants

    E-Print Network [OSTI]

    Mason, Andrew

    to optimize power consumption. The system was designed in 130nm CMOS and shown to occupy 0.082 mm2. Such a system must operate with very low power and occupy minimal area in order to facilitate implantationAdaptive Threshold Spike Detection using Stationary Wavelet Transform for Neural Recording Implants

  9. An Efficient Threshold-Based Power Management Mechanism for Heterogeneous Soft Real-Time Clusters

    E-Print Network [OSTI]

    Lu, Ying

    An Efficient Threshold-Based Power Management Mechanism for Heterogeneous Soft Real-Time Clusters {lwang, ylu}@cse.unl.edu Abstract With growing cost of electricity, the power management of server proposes an efficient algorithm for power management of heterogeneous soft real-time clusters. It is built

  10. EnergySmart: Toward Energy-Efficient Manycores for Near-Threshold Computing

    E-Print Network [OSTI]

    Torrellas, Josep

    and static energy. According to initial estimates [7, 13], NTC can decrease the energy per operationEnergySmart: Toward Energy-Efficient Manycores for Near-Threshold Computing Ulya R. Karpuzcu on-chip voltage (Vdd) domains. However, this paper finds that such an approach is energy inefficient

  11. Measurement of T20,,90... in the 1 He reaction below deuteron breakup threshold

    E-Print Network [OSTI]

    Knutson, Lynn

    to the parametrization of the tensor force in the trinucleon system. The T20 analyzing power was measured at an incidentMeasurement of T20,,90°... in the 1 H,,d, ...3 He reaction below deuteron breakup threshold K. P, Wisconsin 53706 Received 10 November 1995 The tensor analyzing powers of the 1 H(d, )3 He reaction

  12. Threshold phenomena and complexity: a statistical physics analysis of the random

    E-Print Network [OSTI]

    Duxbury, Phillip M.

    Threshold phenomena and complexity: a statistical physics analysis of the random Satis#12;ability problem. R#19;emi Monasson 1 Laboratoire de Physique Th#19;eorique de l'ENS, 75005 Paris. Abstract designed by physicists to deal with optimization or decision problems in an accessible language

  13. Efficient generic on-line/off-line (threshold) signatures without key exposure q

    E-Print Network [OSTI]

    Kim, Kwangjo

    security requirements. Ó 2008 Elsevier Inc. All rights reserved. 1. Introduction The notion of on-line/off-line manufacturing process or as a background computation whenever the card is connected to power, and the on-lineEfficient generic on-line/off-line (threshold) signatures without key exposure q Xiaofeng Chen a

  14. Determination of energy thresholds on an artificial retina using a multiple-pulsed laser

    E-Print Network [OSTI]

    Stephenson, Albert David

    1999-01-01T23:59:59.000Z

    This study is focused on determining single and multiple pulse ED?? for laser pulses of 200 ns duration. Energy thresholds in this experiment were determined on an artificial retina, for a variety of pulse widths and spot sizes. Due to numerous...

  15. ccsd00000619 Phenomenology of the pp ! pp reaction close to threshold

    E-Print Network [OSTI]

    to threshold A. Delo#11; #3; Institute for Nuclear Studies, Ho_za 69, 00-681 Warsaw, Poland (Dated: September 22, 2003) The recent high statistics measurement of the pp ! pp#17; reaction at an excess energy Q=15 on-shell approximation in the enhancement factor and by allowing for a linear energy dependence

  16. The Benard-Von Karman instability : an experimental study near the threshold

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    alternately to form a double row of oppositely signed vortices : the Benard-Von Karman vortex street. PreviousL-483 The Benard-Von Karman instability : an experimental study near the threshold C. Mathis, M features ofthe flow have been known since the work of Benard [3] or Von Karman [4]. For Re 4 the flow

  17. 2[r arrow][ital n] threshold production at the tree level

    SciTech Connect (OSTI)

    Brown, L.S.; Zhai, C. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1993-06-15T23:59:59.000Z

    The threshold behavior of a theory with two coupled scalar fields [chi] and [phi] is investigated. We compute the amplitude for two on-mass-shell [chi] particles to produce an arbitrary number of [phi] particles at rest in the tree approximation.

  18. Total cross section for p + p r arrow p + p +. pi. sup 0 near threshold

    SciTech Connect (OSTI)

    Miller, G.A.; Sauer, P.U. (Department of Physics, FM-15, University of Washington, Seattle, Washington (USA))

    1991-11-01T23:59:59.000Z

    We compare a phenomenology of {pi}{sup 0} production in {ital p}-{ital p} scattering with recent Indiana University Cyclotron Facility data for energies near threshold. The computed magnitude of the cross section is too small by a factor of about 5, even though the energy dependence is satisfactorily described.

  19. NetTRUST: mixed NETworks Trust infrastRUcture baSed on Threshold cryptography

    E-Print Network [OSTI]

    Boyer, Edmond

    NetTRUST: mixed NETworks Trust infrastRUcture baSed on Threshold cryptography Mawloud Omar Re and the performance evaluation prove the adequacy of this solution to mixed networks architectures. Keywords to military applications), but the combination of ad-hoc networks with infrastructure based networks

  20. $J/?$ suppression in the threshold model at RHIC and LHC energy

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2007-11-14T23:59:59.000Z

    In the QGP based threshold model \\cite{Blaizot:2000ev,Blaizot:1996nq}, in addition to the normal nuclear absorption, $J/\\psi$'s are subjected to an 'anomalous' suppression such that above a threshold density $n_{J/\\psi}$, all the $J/\\psi$'s are melted. In the threshold model we have analysed the recent PHENIX data on the centrality dependence of $J/\\psi$ suppression in Au+Au collisions at RHIC. Feedback from decay of the state $\\chi$ is accounted for. $J/\\psi$'s are anomalously suppressed above a threshold density, $n_{J/\\psi}=3.57\\pm 0.17$ $fm^{-2}$. Threshold density for anomalous suppression of the state $\\chi$ is uncertain to a large extent, $n_\\chi=0.32 \\pm 0.32$ $fm^{-2}$. The fraction $F$ of the state $\\chi$ can not be determined unambiguously, depending on the nuclear absorption, it can vary from 20% to 40%. We have also predicted for the suppression in Pb+Pb collisions at LHC energy. In central Pb+Pb collisions, $J/\\psi$'s are suppressed by a factor of 3-4. Suppression pattern is rather similar to that in Au+Au collisions, if not slighty less in central collisions. Using the PHENIX data on the participant number dependence of the Bjorken energy density, we have also estimated the QGP formation time. For critical temperature $T_c$=192 MeV, estimated QGP formation time ranges between 0.07-0.09 fm/c.

  1. Wavelength dependence of the threshold in an InGaP-InAlGaP vertical cavity surface emitting laser

    SciTech Connect (OSTI)

    Chow, W.W.; Schneider, R.P. Jr.; Lott, J.A.; Choquette, K.D. (Sandia National Laboratories, Albuquerque, New Mexico 87185-0350 (United States))

    1994-07-11T23:59:59.000Z

    The wavelength dependence of the threshold in an InGaP-InAlGaP vertical cavity surface emitting laser is investigated using a microscopic theory of the semiconductor gain medium. Good agreement is found between experiment and theory for the minimum threshold lasing wavelength for a range of laser structures.

  2. Mixing of partial waves near B*B?* threshold in e?e? annihilation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Xin; Voloshin, M. B.

    2013-05-01T23:59:59.000Z

    We consider the production of B*B?* meson pairs in e?e? annihilation near the threshold. The rescattering due to pion exchange between the mesons results in a mixing between three partial wave amplitudes: two P-wave amplitudes with the total spin of the meson pair S=0 and S=2 and an F-wave amplitude. The mixing due to pion exchange with a low momentum transfer is calculable up to c.m. energy E?15–20 MeV above the threshold. We find that the P–F mixing is numerically quite small in this energy range, while the mixing of the two P-wave amplitudes is rapidly changing with energy and can reach of order one at such low energies.

  3. Direct Dose Consequences Due to DOE-STD-1027 Threshold Values

    SciTech Connect (OSTI)

    Hochhalter, E Eugene; Durante, Richard Paul; Walker, Jonathon Bill

    2001-06-01T23:59:59.000Z

    The purpose of this paper is to discuss the potential direct dose consequences to facility workers and/or co-located workers from a Hazard Category 2 or 3 nuclear facility or a less than Hazard Category 3 radiological inventory. At the Idaho National Engineering and Environmental Laboratory (INEEL), the safety analysis for several Hazard Category 3 nuclear facilities had to be revisited and the direct dose consequences associated with the facility radiological inventory had to be analyzed and incorporated into the safety analysis. This additional safety analysis was required because it was assumed that for a nuclear facility operating with radiological inventories between the Hazard Category 3 threshold quantities as a lower bounds and less the Hazard Category 2 threshold quantities as an upper bounds, the risk to the facility worker and/or co-located worker was within the INEEL Evaluation Guidelines for radiological exposures.

  4. The effect of a percolation threshold in the Kozeny-Carman relation

    SciTech Connect (OSTI)

    Mavko, G.; Nur, A. [Stanford Univ., CA (United States). Dept. of Geophysics] [Stanford Univ., CA (United States). Dept. of Geophysics

    1997-09-01T23:59:59.000Z

    One of the most important properties of reservoir rocks, and perhaps the most difficult to predict, is permeability. Laboratory studies have shown that permeability depends on a long list of parameters: porosity, pore size and shape, clay content, stress, pore pressure, fluid type, saturation--a nearly overwhelming complexity. In spite of this, the essential behavior can often be expressed successfully using the remarkably simple Kozeny-Carman relation. Numerous authors have studied the role of percolation in both electrical and fluid transport, in particular the details of transport in the neighborhood of the percolation threshold. The goal here is to show that by including the percolation threshold, in a very simple way, in the Kozeny-Carman relation, the derived third-power dependence on porosity can be retained while accurately fitting the observed permeability in certain well sorted materials--thus extending the range of this already useful tool.

  5. Vibrational Feshbach resonances in near threshold HOCO{sup -} photodetachment: a theoretical study

    SciTech Connect (OSTI)

    Miyabe, Shungo; Haxton, Dan; Lawler, Keith; Orel, Ann; McCurdy, Bill; Rescigno, Tom

    2011-03-02T23:59:59.000Z

    The results of a theoretical study of HOCO{sup ?} photodetachment are presented, with a view toward understanding the origin of two peaks observed by Lu and Continetti (Phys. Rev. Lett. 99, 113005 (2007)) in the photoelectron kinetic energy spectrum very close to threshold. It is shown that the peaks can be attributed to vibrational Feshbach resonances of dipole-bound trans-HOCO{sup ?}, and not s- and p-wave shape resonances as previously assumed. Fixed-nuclei variational electron-HOCO scattering calculations are used to compute photodetachment cross sections and laboratory-frame photoelectron angular distributions. The calculations show a broad A??(#25;{pi}*)-shape resonance several eV above threshold.

  6. Interference Oscillations in the Angular Distribution of Laser-Ionized Electrons near Ionization Threshold

    SciTech Connect (OSTI)

    Arbo, D.G.; Yoshida, S.; Persson, E.; Dimitriou, K.I.; Burgdoerfer, J. [Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10/136, A-1040 Vienna (Austria)

    2006-04-14T23:59:59.000Z

    We analyze the two-dimensional momentum distribution of electrons ionized by few-cycle laser pulses in the transition regime from multiphoton absorption to tunneling by solving the time-dependent Schroedinger equation and by a classical-trajectory Monte-Carlo simulation with tunneling (CTMC-T). We find a complex two-dimensional interference pattern that resembles above threshold ionization (ATI) rings at higher energies and displays Ramsauer-Townsend-type diffraction oscillations in the angular distribution near threshold. CTMC-T calculations provide a semiclassical explanation for the dominance of selected partial waves. While the present calculation pertains to hydrogen, we find surprising qualitative agreement with recent experimental data for rare gases [A. Rudenko et al., J. Phys. B 37, L407 (2004)].

  7. Sub-threshold $\\phi$ and $\\Xi^-$ production by high mass resonances with UrQMD

    E-Print Network [OSTI]

    Steinheimer, Jan

    2015-01-01T23:59:59.000Z

    We present a possible explanation for the deep sub-threshold, $\\phi$ and $\\Xi^-$ production yields measured with the HADES experiment in Ar+KCl reactions at $E_{\\mathrm{lab}}=1.76$ A GeV and present predictions for Au+Au reactions at $E_{\\mathrm{lab}}=1.23$ A GeV. To explain the surprisingly high yields of $\\phi$ and $\\Xi^-$ hadrons we propose new decay channels for high mass baryon resonances. These new decay channels are constrained by elementary $\\mathrm{p+p}\\rightarrow \\mathrm{p+p+}\\phi$ cross sections, and $\\Xi^-$ production in p+Nb. Based on the fits to the elementary reactions one obtains a satisfactorily description of $\\phi$ and $\\Xi^-$ production in deep sub-threshold Ar+KCl reactions. The results implicate that no new medium effects are required to describe the rare strange particle production data in low energy nuclear collisions.

  8. Near Threshold Neutral Pion Electroproduction at High Momentum Transfers and Generalized Form Factors

    E-Print Network [OSTI]

    P. Khetarpal; P. Stoler; I. G. Aznauryan; V. Kubarovsky; K. P. Adhikari; D. Adikaram; M. Aghasyan; M. J. Amaryan; M. D. Anderson; S. Anefalos Pereira; M. Anghinolfi; H. Avakian; H. Baghdasaryan; J. Ball; N. A. Baltzell; M. Battaglieri; V. Batourine; I. Bedlinskiy; A. S. Biselli; J. Bono; S. Boiarinov; W. J. Briscoe; W. K. Brooks; V. D. Burkert; D. S. Carman; A. Celentano; G. Charles; P. L. Cole; M. Contalbrigo; V. Crede; A. D'Angelo; N. Dashyan; R. De Vita; E. De Sanctis; A. Deur; C. Djalali; D. Doughty; M. Dugger; R. Dupre; H. Egiyan; A. El Alaoui; L. El Fassi; P. Eugenio; G. Fedotov; S. Fegan; R. Fersch; J. A. Fleming; A. Fradi; M. Y. Gabrielyan; M. Garçon; N. Gevorgyan; G. P. Gilfoyle; K. L. Giovanetti; F. X. Girod; J. T. Goetz; W. Gohn; E. Golovatch; R. W. Gothe; K. A. Griffioen; B. Guegan; M. Guidal; L. Guo; K. Hafidi; H. Hakobyan; C. Hanretty; N. Harrison; K. Hicks; D. Ho; M. Holtrop; C. E. Hyde; Y. Ilieva; D. G. Ireland; B. S. Ishkhanov; E. L. Isupov; H. S. Jo; K. Joo; D. Keller; M. Khandaker; A. Kim; W. Kim; F. J. Klein; S. Koirala; A. Kubarovsky; S. V. Kuleshov; N. D. Kvaltine; S. Lewis; K. Livingston; H. Y. Lu; I. J. D. MacGregor; Y. Mao; D. Martinez; M. Mayer; B. McKinnon; C. A. Meyer; T. Mineeva; M. Mirazita; V. Mokeev; R. A. Montgomery; H. Moutarde; E. Munevar; C. Munoz Camacho; P. Nadel-Turonski; R. Nasseripour; S. Niccolai; G. Niculescu; I. Niculescu; M. Osipenko; A. I. Ostrovidov; L. L. Pappalardo; R. Paremuzyan; K. Park; S. Park; E. Pasyuk; E. Phelps; J. J. Phillips; S. Pisano; O. Pogorelko; S. Pozdniakov; J. W. Price; S. Procureur; D. Protopopescu; A. J. R. Puckett; B. A. Raue; G. Ricco; D. Rimal; M. Ripani; G. Rosner; P. Rossi; F. Sabatié; M. S. Saini; C. Salgado; N. A. Saylor; D. Schott; R. A. Schumacher; E. Seder; H. Seraydaryan; Y. G. Sharabian; G. D. Smith; D. I. Sober; D. Sokhan; S. S. Stepanyan; S. Stepanyan; I. I. Strakovsky; S. Strauch; M. Taiuti; W. Tang; C. E. Taylor; S. Tkachenko; M. Ungaro; B. Vernarsky; H. Voskanyan; E. Voutier; N. K. Walford; L. B. Weinstein; D. P. Weygand; M. H. Wood; N. Zachariou; J. Zhang; Z. W. Zhao; I. Zonta

    2012-11-29T23:59:59.000Z

    We report the measurement of near threshold neutral pion electroproduction cross sections and the extraction of the associated structure functions on the proton in the kinematic range $Q^2$ from 2 to 4.5 GeV$^2$ and $W$ from 1.08 to 1.16 GeV. These measurements allow us to access the dominant pion-nucleon s-wave multipoles $E_{0+}$ and $S_{0+}$ in the near-threshold region. In the light-cone sum-rule framework (LCSR), these multipoles are related to the generalized form factors $G_1^{\\pi^0 p}(Q^2)$ and $G_2^{\\pi^0 p}(Q^2)$. The data are compared to these generalized form factors and the results for $G_1^{\\pi^0 p}(Q^2)$ are found to be in good agreement with the LCSR predictions, but the level of agreement with $G_2^{\\pi^0 p}(Q^2)$ is poor.

  9. Stability threshold of ion temperature gradient driven mode in reversed field pinch plasmas

    SciTech Connect (OSTI)

    Guo, S. C. [Consorzio RFX, Associazione Euratom-ENEA sulla fusione, Corso Stati Uniti 4, Padova 35127 (Italy)

    2008-12-15T23:59:59.000Z

    For the first time in the reversed field pinch (RFP) configuration, the stability threshold of the ion temperature gradient driven (ITG) mode is studied by linear gyrokinetic theory. In comparison with tokamaks, the RFP configuration has a shorter connection length and stronger magnetic curvature drift. These effects result in a stronger instability driving mechanism and a larger growth rate in the fluid limit. However, the kinetic theory shows that the temperature slopes required for the excitation of ITG instability are much steeper than the tokamak ones. This is because the effect of Landau damping also becomes stronger due to the shorter connection length, which is dominant and ultimately determines the stability threshold. The required temperature slope for the instability may only be found in the very edge of the plasma and/or near the border of the dominant magnetic island during the quasi-single helicity state of discharge.

  10. Surface mobility near threshold and other parameters of insulated gate field effect transistors

    E-Print Network [OSTI]

    Gnadinger, Alfred P.

    1970-01-01T23:59:59.000Z

    SURFACE MOBILITY NEAR THRESHOLD AND OTHER PARAMETERS OF INSULATED GATE FIELD EFFECT TRANSISTORS BY Alfred P. Gnadinger Dipl. El. Ing. ETH Swiss Federal Institute of Technology, Zurich, 1965 M.S.E.E, University of Kansas, Lawrence, 1968... Committee: May, 1970 RD0107 4S0S0 TO MY WIFE AND OUR PARENTS i ABSTRACT The mobility of the mobile carriers in the inversion layer of an Insulated Gate Field Effect Transistor (IGFET) has been investigated with particular...

  11. Elastic proton scattering on tritium below the n-$^{3}{He}$ threshold

    E-Print Network [OSTI]

    Rimantas Lazauskas

    2009-03-27T23:59:59.000Z

    Elastic proton scattering on ${}^{3}{H}$ nucleus is studied inbetween p-% ${}^{3}{H}$ and n-${}^{3}{He}$ thresholds, in the energy region where $\\alpha$-particles first excited state is inbeded in the continuum. For this aim Faddeev-Yakubovski equations are solved in configuration space, fully considering effects due to the isospin breaking as well as rigorously treating Coulomb interaction. Different realistic nuclear Hamiltonians are tested, elucidating open problems in nuclear interaction description.

  12. Electron-Positron Pair Production by an Electron in a Magnetic Field Near the Process Threshold

    E-Print Network [OSTI]

    O. P. Novak; R. I. Kholodov; P. I. Fomin

    2011-01-13T23:59:59.000Z

    The electron-positron pair production by an electron in a strong magnetic field near the process threshold is considered. The process is shown to be more probable if the spin of the initial electron is oriented along the field. In this case, the probability of the process is $\\sim10^{13} s^{-1}$ when the magnetic field strength is $H=4\\cdot 10^{12}$ G.

  13. Limiting absorption principle for some long range perturbations of Dirac systems at threshold energies

    E-Print Network [OSTI]

    Nabile Boussaid; Sylvain Golénia

    2009-06-08T23:59:59.000Z

    We establish a limiting absorption principle for some long range perturbations of the Dirac systems at threshold energies. We cover multi-center interactions with small coupling constants. The analysis is reduced to study a family of non-self-adjoint operators. The technique is based on a positive commutator theory for non self-adjoint operators, which we develop in appendix. We also discuss some applications to the dispersive Helmholzt model in the quantum regime.

  14. Intensity-dependent enhancements in high-order above-threshold ionization

    SciTech Connect (OSTI)

    Milosevic, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany); Hasovic, E.; Gazibegovic-Busuladzic, A. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo, Bosnia and Herzegovina (Bosnia and Herzegowina); Busuladzic, M. [Medical Faculty, University of Sarajevo, Cekalusa 90, 71000 Sarajevo (Bosnia and Herzegowina); Becker, W. [Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany)

    2007-11-15T23:59:59.000Z

    The very pronounced intensity-dependent enhancements of groups of peaks of high-order above-threshold-ionization spectra of rare-gas atoms are investigated using an improved version of the strong-field approximation, which realistically models the respective atom. Two types of enhancements are found and explained in terms of constructive interference of the contributions of a large number of long quantum orbits. The first type is observed for intensities slightly below channel closings. Its intensity dependence is comparatively smooth and it is generated by comparatively few (of the order of 20) orbits. The second type occurs precisely at channel closings and exhibits an extremely sharp intensity dependence. It requires constructive interference of a very large number of long orbits (several hundreds) and generates cusps in the electron spectrum at integer multiples of the laser-photon energy. An interpretation of these enhancements as a threshold phenomenon is also given. An interplay of different types of the threshold anomalies is observed. The position of both types of enhancements, in the photoelectron-energy--laser-intensity plane, shifts to the next channel closing intensity with the change of the ground-state parity. The enhancements gradually disappear with decreasing laser pulse duration. This confirms the interpretation of enhancements as a consequence of the interference of long strong-laser-field-induced quantum orbits.

  15. Interplay of threshold resummation and hadron mass corrections in deep inelastic processes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Accardi, Alberto; Anderle, Daniele P.; Ringer, Felix

    2015-02-01T23:59:59.000Z

    We discuss hadron mass corrections and threshold resummation for deep-inelastic scattering lN-->l'X and semi-inclusive annihilation e+e- -->hX processes, and provide a prescription how to consistently combine these two corrections respecting all kinematic thresholds. We find an interesting interplay between threshold resummation and target mass corrections for deep-inelastic scattering at large values of Bjorken xB. In semi-inclusive annihilation, on the contrary, the two considered corrections are relevant in different kinematic regions and do not affect each other. A detailed analysis is nonetheless of interest in the light of recent high precision data from BaBar and Belle on pion and kaon production,more »with which we compare our calculations. For both deep inelastic scattering and single inclusive annihilation, the size of the combined corrections compared to the precision of world data is shown to be large. Therefore, we conclude that these theoretical corrections are relevant for global QCD fits in order to extract precise parton distributions at large Bjorken xB, and fragmentation functions over the whole kinematic range.« less

  16. Interplay of threshold resummation and hadron mass corrections in deep inelastic processes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Accardi, Alberto; Anderle, Daniele P.; Ringer, Felix

    2015-02-01T23:59:59.000Z

    We discuss hadron mass corrections and threshold resummation for deep-inelastic scattering lN-->l'X and semi-inclusive annihilation e+e- -->hX processes, and provide a prescription how to consistently combine these two corrections respecting all kinematic thresholds. We find an interesting interplay between threshold resummation and target mass corrections for deep-inelastic scattering at large values of Bjorken xB. In semi-inclusive annihilation, on the contrary, the two considered corrections are relevant in different kinematic regions and do not affect each other. A detailed analysis is nonetheless of interest in the light of recent high precision data from BaBar and Belle on pion and kaon production, with which we compare our calculations. For both deep inelastic scattering and single inclusive annihilation, the size of the combined corrections compared to the precision of world data is shown to be large. Therefore, we conclude that these theoretical corrections are relevant for global QCD fits in order to extract precise parton distributions at large Bjorken xB, and fragmentation functions over the whole kinematic range.

  17. Renormalization Group Evolution of Neutrino Parameters in Presence of Seesaw Threshold Effects and Majorana Phases

    E-Print Network [OSTI]

    Shivani Gupta; Sin Kyu Kang; C. S. Kim

    2015-02-01T23:59:59.000Z

    We examine the renormalization group evolution (RGE) for different mixing scenarios in the presence of seesaw threshold effects from high energy scale (GUT) to the low electroweak (EW) scale in the Standard Model (SM) and Minimal Supersymmetric Standard Model (MSSM). We consider four mixing scenarios namely Tri-Bimaximal Mixing, Bimaximal Mixing, Hexagonal Mixing and Golden Ratio Mixing which come from different flavor symmetries at the GUT scale. We find that the Majorana phases play an important role in the RGE running of these mixing patterns along with the seesaw threshold corrections. We present a comparative study of the RGE of all these mixing scenarios both with and without Majorana CP phases when seesaw threshold corrections are taken into consideration. We find that in the absence of these Majorana phases both the RGE running and seesaw effects may lead to $\\theta_{13}energies both in the SM and MSSM. However, if the Majorana phases are incorporated to the mixing matrix the running can be enhanced both in the SM and MSSM. Even by incorporating non zero Majorana CP phases in the SM, we do not get $\\theta_{13}$ in its present 3$\\sigma$ range. The current values of the two mass squared differences and mixing angles including $\\theta_{13}$ can be produced in the MSSM case with tan$\\beta$ = 10 and non zero Majorana CP phases at low energy. We also calculate the order of effective Majorana mass and Jarlskog Invariant for each scenario under consideration.

  18. Imaging properties of the Medipix2 system exploiting single and dual energy thresholds

    E-Print Network [OSTI]

    Tlustos, Lukas; Campbell, Michael; Heijne, Erik H M; Kincade, Karla Lorraine; Llopart-Cudie, Xavier; Stejskal, Pavel

    2006-01-01T23:59:59.000Z

    Low noise, high resolution and high dose efficiency are the common requirements for most X-ray imaging applications. Especially in medical applications the dose efficiency is a necessity for detector systems. We present the imaging performance of the Medipix2 readout chip bump bonded to a 300 mu m thick Si detector as a function of the detection threshold, a free parameter not available in conventional integrating imaging systems. Spatial resolution has been measured using the modulation transfer function (MTF) and it varies between 8.2 Ip/mm and 11.0 Ip/mm at 70%. An associated measurement of noise power spectrum (NPS) permits us to derive the detective quantum efficiency (DQE) which can be as a high as 25.5 % for a broadband incoming spectrum. The influence of charge diffusion in the sensor together with threshold variation in the readout chip is discussed. Although the Medipix2 system is used in photon counting mode with a single threshold in energy, the system is also capable of counting within a given en...

  19. A Low-threshold Analysis of CDMS Shallow-site Data

    SciTech Connect (OSTI)

    Akerib, D.S.; /Case Western Reserve U.; Attisha, M.J.; /Brown U.; Baudis, L.; /Zurich-Irchel U.; Bauer, D.A.; /Fermilab; Bolozdynya, A.I.; /Case Western Reserve U.; Brink, P.L.; /SLAC; Bunker, R.; /UC, Santa Barbara; Cabrera, B.; /Stanford U., Phys. Dept.; Caldwell, D.O.; /UC, Santa Barbara; Chang, C.L.; /Stanford U., Phys. Dept.; Clarke, R.M.; /Stanford U., Phys. Dept.; Cooley, J.; /Southern Methodist U.; Crisler, M.B.; /Fermilab; Cushman, P.; /Minnesota U.; DeJongh, F.; /Fermilab; Dixon, R.; /Fermilab; Driscoll, D.D.; /Case Western Reserve U.; Filippini, J.; /Caltech; Funkhouser, S.; /UC, Berkeley; Gaitskell, R.J.; /Brown U.; Golwala, S.R.; /Caltech /Fermilab /Fermilab /Colorado U., Denver /Case Western Reserve U. /Texas A-M /Minnesota U. /UC, Berkeley /UC, Berkeley /Caltech /Stanford U., Phys. Dept. /UC, Santa Barbara /Stanford U., Phys. Dept. /Minnesota U. /Queen's U., Kingston /Minnesota U. /St. Olaf Coll. /Florida U. /LBL, Berkeley /UC, Berkeley /Texas A-M /UC, Santa Barbara /Syracuse U. /UC, Berkeley /Princeton U. /Case Western Reserve U. /Stanford U., Phys. Dept. /UC, Santa Barbara /Fermilab /Santa Clara U.

    2012-06-04T23:59:59.000Z

    Data taken during the final shallow-site run of the first tower of the Cryogenic Dark Matter Search (CDMS II) detectors have been reanalyzed with improved sensitivity to small energy depositions. Four {approx}224 g germanium and two {approx}105 g silicon detectors were operated at the Stanford Underground Facility (SUF) between December 2001 and June 2002, yielding 118 live days of raw exposure. Three of the germanium and both silicon detectors were analyzed with a new low-threshold technique, making it possible to lower the germanium and silicon analysis thresholds down to the actual trigger thresholds of {approx}1 and {approx}2 keV, respectively. Limits on the spin-independent cross section for weakly interacting massive particles (WIMPs) to elastically scatter from nuclei based on these data exclude interesting parameter space for WIMPs with masses below 9 GeV/c{sup 2}. Under standard halo assumptions, these data partially exclude parameter space favored by interpretations of the DAMA/LIBRA and CoGeNT experiments data as WIMP signals, and exclude new parameter space for WIMP masses between 3 and 4 GeV/c{sup 2}.

  20. A low-threshold analysis of CDMS shallow-site data

    SciTech Connect (OSTI)

    Akerib, D.S.; /Case Western Reserve U.; Attisha, M.J.; /Brown U.; Baudis, L.; /Zurich-Irchel U.; Bauer, D.A.; /Fermilab; Bolozdynya, A.I.; /Case Western Reserve U.; Brink, P.L.; /SLAC; Bunker, R.; /UC, Santa Barbara; Cabrera, B.; /Stanford U., Phys. Dept.; Caldwell, D.O.; /UC, Santa Barbara; Chang, C.L.; /Stanford U., Phys. Dept.; Clarke, R.M.; /Stanford U., Phys. Dept. /Southern Methodist U.

    2010-10-01T23:59:59.000Z

    Data taken during the final shallow-site run of the first tower of the Cryogenic Dark Matter Search (CDMS II) detectors have been reanalyzed with improved sensitivity to small energy depositions. Four {approx}224 g germanium and two {approx}105 g silicon detectors were operated at the Stanford Underground Facility (SUF) between December 2001 and June 2002, yielding 118 live days of raw exposure. Three of the germanium and both silicon detectors were analyzed with a new low-threshold technique, making it possible to lower the germanium and silicon analysis thresholds down to the actual trigger thresholds of {approx}1 keV and {approx}2 keV, respectively. Limits on the spin-independent cross section for weakly interacting massive particles (WIMPs) to elastically scatter from nuclei based on these data exclude interesting parameter space for WIMPs with masses below 9 GeV/c{sup 2}. Under standard halo assumptions, these data partially exclude parameter space favored by interpretations of the DAMA/LIBRA and CoGeNT experiments data as WIMP signals, and exclude new parameter space for WIMP masses between 3 GeV/c{sup 2} and 4 GeV/c{sup 2}.

  1. Theoretical Limit to the Laser Threshold Current Density in an InGaN Quantume Well Laser

    SciTech Connect (OSTI)

    Amano, H; Chow, W W; Han, J

    1998-10-09T23:59:59.000Z

    This paper describes an investigation of the spontaneous emission limit to the laser threshold current density in an InGaN quantum well laser. The peak gain and spontaneous emission rate as functions of carrier density are com- puted using a microscopic laser theory. From these quantities, the minimum achievable threshold current density is determined for a given threshold gain. The dependence on quantum well width, and the effects of inhomogeneous broadening due to spatial alloy variations are discussed. Also, comparison with experiments is made.

  2. Method for improving instrument response

    DOE Patents [OSTI]

    Hahn, David W. (7528 Oxford Cir., Dublin, Alameda County, CA 94568); Hencken, Kenneth R. (2665 Calle Alegre, Pleasanton, Alameda County, CA 94566); Johnsen, Howard A. (5443 Celeste Ave., Livermore, Alameda County, CA 94550); Flower, William L. (5447 Theresa Way, Livermore, Alameda County, CA 94550)

    2000-01-01T23:59:59.000Z

    This invention pertains generally to a method for improving the accuracy of particle analysis under conditions of discrete particle loading and particularly to a method for improving signal-to-noise ratio and instrument response in laser spark spectroscopic analysis of particulate emissions. Under conditions of low particle density loading (particles/m.sup.3) resulting from low overall metal concentrations and/or large particle size uniform sampling can not be guaranteed. The present invention discloses a technique for separating laser sparks that arise from sample particles from those that do not; that is, a process for systematically "gating" the instrument response arising from "sampled" particles from those responses which do not, is dislosed as a solution to his problem. The disclosed approach is based on random sampling combined with a conditional analysis of each pulse. A threshold value is determined for the ratio of the intensity of a spectral line for a given element to a baseline region. If the threshold value is exceeded, the pulse is classified as a "hit" and that data is collected and an average spectrum is generated from an arithmetic average of "hits". The true metal concentration is determined from the averaged spectrum.

  3. Zero Kinetic Energy Photofragment Spectroscopy: The Threshold Dissociation of NO2 J. A. Mueller, S. A. Rogers, and Paul L. Houston*

    E-Print Network [OSTI]

    Houston, Paul L.

    at the dissociation threshold of, while for higher energies, a new peak occurs as the energy threshold is reachedZero Kinetic Energy Photofragment Spectroscopy: The Threshold Dissociation of NO2 J. A. Mueller, S. A. Rogers, and Paul L. Houston* Department of Chemistry, Cornell UniVersity, Ithaca, New York 14853

  4. Method and apparatus for analog pulse pile-up rejection

    DOE Patents [OSTI]

    De Geronimo, Gianluigi

    2013-12-31T23:59:59.000Z

    A method and apparatus for pulse pile-up rejection are disclosed. The apparatus comprises a delay value application constituent configured to receive a threshold-crossing time value, and provide an adjustable value according to a delay value and the threshold-crossing time value; and a comparison constituent configured to receive a peak-occurrence time value and the adjustable value, compare the peak-occurrence time value with the adjustable value, indicate pulse acceptance if the peak-occurrence time value is less than or equal to the adjustable value, and indicate pulse rejection if the peak-occurrence time value is greater than the adjustable value.

  5. Method and apparatus for analog pulse pile-up rejection

    DOE Patents [OSTI]

    De Geronimo, Gianluigi

    2014-11-18T23:59:59.000Z

    A method and apparatus for pulse pile-up rejection are disclosed. The apparatus comprises a delay value application constituent configured to receive a threshold-crossing time value, and provide an adjustable value according to a delay value and the threshold-crossing time value; and a comparison constituent configured to receive a peak-occurrence time value and the adjustable value, compare the peak-occurrence time value with the adjustable value, indicate pulse acceptance if the peak-occurrence time value is less than or equal to the adjustable value, and indicate pulse rejection if the peak-occurrence time value is greater than the adjustable value.

  6. Above-threshold multiphoton detachment from the H- ion by 10.6-?m radiation: Angular distributions and partial widths

    E-Print Network [OSTI]

    Chu, Shih-I; Telnov, Dmitry A.

    1994-11-01T23:59:59.000Z

    We present a general procedure for accurate nonperturbative treatment of the angular distribution and partial widths for multiphoton above-threshold detachment (ATD) of atoms or negative ions in intense laser fields. The procedure consists...

  7. Anomaly in the K^0_S Sigma^+ photoproduction cross section off the proton at the K* threshold

    E-Print Network [OSTI]

    R. Ewald; A. V. Anisovich; B. Bantes; O. Bartholomy; D. Bayadilov; R. Beck; Y. A. Beloglazov; K. -T. Brinkmann; V. Crede; H. Dutz; D. Elsner; K. Fornet-Ponse; F. Frommberger; Ch. Funke; A. B. Gridnev; E. Gutz; W. Hillert; J. Hannappel; P. Hoffmeister; I. Jaegle; O. Jahn; T. Jude; J. Junkersfeld; H. Kalinowsky; S. Kammer; V. Kleber; Frank Klein; Friedrich Klein; E. Klempt; B. Krusche; M. Lang; H. Löhner; I. V. Lopatin; D. Menze; T. Mertens; J. G. Messchendorp; V. Metag; M. Nanova; V. A. Nikonov; D. Novinski; R. Novotny; M. Ostrick; L. Pant; H. van Pee; A. Roy; A. V. Sarantsev; S. Schadmand; Ch. Schmidt; H. Schmieden; B. Schoch; S. Shende; V. Sokhoyan; A. Süle; V. V. Sumachev; T. Szczepanek; U. Thoma; D. Trnka; R. Varma; D. Walther; Ch. Wendel

    2011-12-04T23:59:59.000Z

    The $\\gamma + p \\rightarrow K^0 + \\Sigma^+$ photoproduction reaction is investigated in the energy region from threshold to $E_\\gamma = 2250$\\,MeV. The differential cross section exhibits increasing forward-peaking with energy, but only up to the $K^*$ threshold. Beyond, it suddenly returns to a flat distribution with the forward cross section dropping by a factor of four. In the total cross section a pronounced structure is observed between the $K^*\\Lambda$ and $K^*\\Sigma$ thresholds. It is speculated whether this signals the turnover of the reaction mechanism from t-channel exchange below the $K^*$ production threshold to an s-channel mechanism associated with the formation of a dynamically generated $K^*$-hyperon intermediate state.

  8. Evidence of a Threshold Wind Speed in Tower-mounted Scatterometer Data David W. Draper and David G. Long

    E-Print Network [OSTI]

    Long, David G.

    . Evidence of the threshold wind speed and a hysteresis effect have been observed in airship and wave tank in airship data [2]. YSCAT, an ultra-wideband (2-14 GHz) tower-mounted scat- terometer, provides significant

  9. Wave-packet propagation based calculation of above-threshold ionization in the x-ray regime

    E-Print Network [OSTI]

    Tilley, Matthew; Santra, Robin

    2015-01-01T23:59:59.000Z

    We investigate the multi-photon process of above-threshold ionization for the light elements hydrogen, carbon, nitrogen and oxygen in the hard x-ray regime. Numerical challenges are discussed and by comparing Hartree-Fock-Slater calculations to configuration-interaction-singles results we justify the mean-field potential approach in this regime. We present a theoretical prediction of two-photon above-threshold-ionization cross sections for the mentioned elements. Moreover, we study how the importance of above-threshold ionization varies with intensity. We find that for carbon, at x-ray intensities around $10^{23}{\\rm Wcm}^{-2}$, two-photon above-threshold ionization of the K-shell electrons is as probable as one-photon ionization of the L-shell electrons.

  10. Identification of the stimulated-emission threshold in high-{beta} nanoscale lasers through phase-space reconstruction

    SciTech Connect (OSTI)

    Hachair, X.; Elvira, D.; Le Gratiet, L.; Lemaitre, A.; Abram, I.; Sagnes, I.; Robert-Philip, I.; Beveratos, A. [Laboratoire de Photonique et de Nanostructures, CNRS-UPR20, Route de Nozay, 91460 Marcoussis (France); Braive, R. [Laboratoire de Photonique et de Nanostructures, CNRS-UPR20, Route de Nozay, 91460 Marcoussis (France); Universite Paris Denis Diderot, 75205 Paris, Cedex 13 (France); Lippi, G. L. [Institut Non Lineaire de Nice, Universite de Nice-Sophia Antipolis, 1361 Route des Lucioles, F-06560 Valbonne (France); Institut Non Lineaire de Nice, CNRS UMR 6618, 1361 Route des Lucioles, F-06560 Valbonne (France)

    2011-05-15T23:59:59.000Z

    Nanoscale lasers sustain a few optical modes so that the fraction of spontaneous emission {beta} funnelled into the useful (lasing) mode is high (of the order of 10{sup -1}) and the threshold, which traditionally corresponds to an abrupt kink in the light-in-light-out curve, becomes ill defined. We propose an alternative definition of the threshold that is based on the dynamical response of the laser and is valid even for {beta}=1 lasers. The laser dynamics is analyzed through a reconstruction of its phase-space trajectory for pulsed excitations. Crossing the threshold, brings about a change in the shape of the trajectory and in the area contained in it. An unambiguous determination of the threshold in terms of this change is shown theoretically and illustrated experimentally in a photonic-crystal laser.

  11. Measurement and modeling of infrared nonlinear absorption coefficients and laser-induced damage thresholds in Ge and GaSb

    SciTech Connect (OSTI)

    Wagner, T. J.; Bohn, M. J.; Coutu, R. A. Jr. [Air Force Institute of Technology, Wright Patterson Air Force Base, Ohio 45433 (United States); Gonzalez, L. P.; Murray, J. M.; Guha, S. [Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright Patterson Air Force Base, Ohio 45433 (United States); Schepler, K. L. [Air Force Research Laboratory, Sensors Directorate, Wright Patterson Air Force Base, Ohio 45433 (United States)

    2010-10-15T23:59:59.000Z

    Using a simultaneous fitting technique to extract nonlinear absorption coefficients from data at two pulse widths, we measure two-photon and free-carrier absorption coefficients for Ge and GaSb at 2.05 and 2.5 {mu}m for the first time, to our knowledge. Results agreed well with published theory. Single-shot damage thresholds were also measured at 2.5 {mu}m and agreed well with modeled thresholds using experimentally determined parameters including nonlinear absorption coefficients and temperature dependent linear absorption. The damage threshold for a single-layer Al{sub 2}O{sub 3} anti-reflective coating on Ge was 55% or 35% lower than the uncoated threshold for picosecond or nanosecond pulses, respectively.

  12. Multiple pulse thermal damage thresholds of materials for x-ray free electron laser optics investigated with an ultraviolet laser

    SciTech Connect (OSTI)

    Hau-Riege, Stefan P.; London, Richard A.; Bionta, Richard M.; Soufli, Regina; Ryutov, Dmitri; Shirk, Michael; Baker, Sherry L. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94539 (United States); Smith, Patrick M.; Nataraj, Pradeep [Kovio, Inc., 1145 Sonora Court, Sunnyvale, California 94086 (United States)

    2008-11-17T23:59:59.000Z

    Optical elements to be used for x-ray free electron lasers (XFELs) must withstand multiple high-fluence pulses. We have used an ultraviolet laser to study the damage of two candidate materials, crystalline Si and B{sub 4}C-coated Si, emulating the temperature profile expected to occur in optics exposed to XFEL pulses. We found that the damage threshold for 10{sup 5} pulses is {approx}20% to 70% lower than the melting threshold.

  13. The Fermi-Pasta-Ulam problem revisited: stochasticity thresholds in nonlinear Hamiltonian systems

    E-Print Network [OSTI]

    Lapo Casetti; Monica Cerruti-Sola; Marco Pettini; E. G. D. Cohen

    1998-04-21T23:59:59.000Z

    The Fermi-Pasta-Ulam $\\alpha$-model of harmonic oscillators with cubic anharmonic interactions is studied from a statistical mechanical point of view. Systems of N= 32 to 128 oscillators appear to be large enough to suggest statistical mechanical behavior. A key element has been a comparison of the maximum Lyapounov coefficient $\\lambda_{max}$ of the FPU $\\alpha$-model and that of the Toda lattice. For generic initial conditions, $\\lambda_{max}(t)$ is indistinguishable for the two models up to times that increase with decreasing energy (at fixed N). Then suddenly a bifurcation appears, which can be discussed in relation to the breakup of regular, soliton-like structures. After this bifurcation, the $\\lambda_{max}$ of the FPU model appears to approach a constant, while the $\\lambda_{max}$ of the Toda lattice appears to approach zero, consistent with its integrability. This suggests that for generic initial conditions the FPU $\\alpha$-model is chaotic and will therefore approach equilibrium and equipartition of energy. There is, however, a threshold energy density $\\epsilon_c(N)\\sim 1/N^2$, below which trapping occurs; here the dynamics appears to be regular, soliton-like and the approach to equilibrium - if any - takes longer than observable on any available computer. Above this threshold the system appears to behave in accordance with statistical mechanics, exhibiting an approach to equilibrium in physically reasonable times. The initial conditions chosen by Fermi, Pasta and Ulam were not generic and below threshold and would have required possibly an infinite time to reach equilibrium.

  14. Dynamics of $K^+$ Production in Heavy Ion Collisions close to Threshold

    E-Print Network [OSTI]

    Christoph Hartnack

    2005-07-01T23:59:59.000Z

    In this article the production of $K^+$ at energies close to the threshold is studied in detail. The production mechanisms, the influence of in-medium effects, cross sections, the nuclear equation of state and the dynamics of the nucleons on the kaon dynamics are discussed. A special regard will be taken on the collision of Au+Au at 1.5 GeV, a reaction that has recently been analyzed in detail by experiments performed by the KaoS and FOPI collaborations at the SIS accelerator at GSI.

  15. Kinetic Model for a Threshold Filter in an Enzymatic System for Bioanalytical and Biocomputing Applications

    E-Print Network [OSTI]

    Vladimir Privman; Sergii Domanskyi; Shay Mailloux; Yaovi Holade; Evgeny Katz

    2014-11-09T23:59:59.000Z

    A recently experimentally observed biochemical "threshold filtering" mechanism by processes catalyzed by the enzyme malate dehydrogenase is explained in terms of a model that incorporates an unusual mechanism of inhibition of this enzyme that has a reversible mechanism of action. Experimental data for a system in which the output signal is produced by biocatalytic processes of the enzyme glucose dehydrogenase are analyzed to verify the model's validity. We also establish that fast reversible conversion of the output product to another compound, without the additional inhibition, cannot on its own result in filtering.

  16. Systematics of threshold incident energy for deep sub-barrier fusion hindrance

    E-Print Network [OSTI]

    Takatoshi Ichikawa; Kouichi Hagino; Akira Iwamoto

    2007-04-21T23:59:59.000Z

    We systematically evaluate the potential energy at the touching configuration for heavy-ion reactions using various potential models. We point out that the energy at the touching point, especially that estimated with the Krappe-Nix-Sierk (KNS) potential, strongly correlates with the threshold incident energy for steep fall-off of fusion cross sections observed recently for several systems at extremely low energies. This clearly indicates that the steep fall-off phenomenon can be attributed to the dynamics after the target and projectile touch with each other, e.g., the tunneling process and the nuclear saturation property in the overlap region.

  17. Single-growth embedded epitaxy AlGaAs injection lasers with extremely low threshold currents

    SciTech Connect (OSTI)

    Katz, J.; Margalit, S.; Wilt, D.; Chen, P.C.; Yariv, A.

    1980-12-01T23:59:59.000Z

    A new type of strip-geometry AlGaAs double-heterostructure laser with an embedded optical waveguide has been developed. The new structure is fabricated using a single step of epitaxial growth. Lasers with threshold currents as low as 9.5 mA (150 ..mu..m long) were obtained. These lasers exhibit operation in a single spatial and longitudinal mode, have differential quantum efficiencies exceeding 45%, and a characteristic temperature of 175/sup 0/ C. They emit more than 12 mW/facet of optical power without any kinks.

  18. Final state interactions at the threshold of Higgs boson pair production

    E-Print Network [OSTI]

    Zhang, Zhentao

    2015-01-01T23:59:59.000Z

    We study the effect of final state interactions at the threshold of Higgs boson pair production in the Glashow-Weinberg-Salam model. We consider three major processes of the pair production in the model: lepton pair annihilation, ZZ fusion, and WW fusion. We find that the corrections caused by the effect for these processes are markedly different. According to our results, the effect can cause non-negligible corrections to the cross sections for lepton pair annihilation and small corrections for ZZ fusion, and this effect is negligible for WW fusion.

  19. Threshold conditions for lasing of a free electron laser oscillator with longitudinal electrostatic wiggler

    SciTech Connect (OSTI)

    Sepehri Javan, N. [Department of Physics, Faculty of Sciences, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, 56199-11367 (Iran, Islamic Republic of)

    2012-12-15T23:59:59.000Z

    The system of the nonlinear non-stationary equations describing spatial-temporal dynamics of the amplitudes of an ondulator radiation and a space-charge wave of a relativistic electron beam in the resonator is obtained. A free electron laser resonator with longitudinal electrostatic wiggler is considered. In the linear approximation, the threshold conditions of lasing for Raman and Compton regimes under excitation of forward and backward electromagnetic wave are achieved. In the various physical situations, the variation of the minimum length of the resonator with the amplitude of wiggler, density of electron beam, and with the reflection coefficients of resonator's mirrors is investigated.

  20. 190-fs passively mode-locked thulium fiber laser with a low threshold

    SciTech Connect (OSTI)

    Sharp, R.C.; Spock, D.E.; Pan, N.; Elliot, J. [Raytheon Company, Electronic Systems, 131 Spring Street, Lexington, Massachusetts 02173 (United States)

    1996-06-01T23:59:59.000Z

    We report a self-starting passively mode-locked thulium-doped silica fiber laser capable of 190-fs pulses. This practical, compact package is driven by a single 50-mW passively cooled diode laser, has a launched pump-power threshold of 18 mW for mode locking, and produces a 50-MHz train of mode-locked 20-pJ pulses at a wavelength near 1.9 {mu}m. {copyright} {ital 1996 Optical Society of America.}

  1. Energy scan by $?$ mesons and threshold energy for the confinement-deconfinement phase transition

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2010-05-18T23:59:59.000Z

    We argue that the ratio of $\\phi$ mesons multiplicity over cube of the mean $p_T$ is proportional to the degeneracy of the medium produced in ultra-relativistic heavy ion collisions. The ratio extracted from the existing $\\phi$ meson data in the energy range $\\sqrt{s}$=6.3-200 GeV, indicate that beyond a threshold energy $\\sqrt{s}_{th}=15.74\\pm 8.10$ GeV, the medium crosses over from a confined phase to a deconfined phase.

  2. Crack closure effects on fatigue crack growth thresholds and remaining life in an HSLA steel

    SciTech Connect (OSTI)

    Todd, J.A.; Mostovoy, S. [Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Mechanical, Materials and Aerospace Engineering; Chen, L. [Texas Instruments, Attleboro, MA (United States); Yankov, E.Y. [A. Finkl and Sons, Chicago, IL (United States)

    1997-02-01T23:59:59.000Z

    The effects of crack closure on the near-threshold corrosion fatigue crack growth behavior of Mil S-24645 HSLA steel and its weld metal have been investigated in air, ASTM seawater at the free corrosion potential, and ASTM seawater at {minus}0.8V and {minus}1.0V (SCE) using frequencies of 10, 2, and 0.2 Hz, and a stress ratio, R = 0.1. Remaining life, in the presence and absence of crack closure, has been estimated as a function of applied stress range for a structure containing a 3-mm-deep surface semi-elliptical flaw.

  3. Multiscale analysis of the laser-induced damage threshold in optical coatings

    SciTech Connect (OSTI)

    Capoulade, Jeremie; Gallais, Laurent; Natoli, Jean-Yves; Commandre, Mireille

    2008-10-10T23:59:59.000Z

    We have investigated the influence of laser beam size on laser-induced damage threshold (LIDT) in the case of single- and multiple-shot irradiation. The study was performed on hafnia thin films deposited with various technologies (evaporation, sputtering, with or without ion assistance). LIDT measurements were carried out at 1064 nm and 12 ns with a spot size ranging from a few tens to a few hundreds of micrometers, in 1-on-1 and R-on-1 modes. These measurements were compared with simulations obtained with the statistical theory of laser-induced damage caused by initiating inclusions.

  4. Modeling of recurrent threshold crossings due to noise with long memory

    E-Print Network [OSTI]

    Singh, Abhishek Narayan

    2007-04-25T23:59:59.000Z

    of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee: Laszlo B. Kish Committee Members: Don R. Halverson C.B. William H. Marlow....S., The University of Texas at Arlington Chair of Advisory Committee: Dr. Laszlo B. Kish This thesis addresses the recurrent threshold crossing behavior of long-time correlated noise. The behavior of long-time correlated noise like f , 5.1 , and 2 can...

  5. Empirical Evaluation of a New Method for Calculating Signal to Noise Ratio (SNR) for Microarray Data Analysis

    SciTech Connect (OSTI)

    Zhou, Jizhong; He, Zhili; Zhou, Jizhong

    2008-03-06T23:59:59.000Z

    Signal-to-noise-ratio (SNR) thresholds for microarray data analysis were experimentally determined with an oligonucleotide array that contained perfect match (PM) and mismatch (MM) probes based upon four genes from Shewanella oneidensis MR-1. A new SNR calculation, called signal to both standard deviations ratio (SSDR) was developed, and evaluated along with other two methods, signal to standard deviation ratio (SSR), and signal to background ratio (SBR). At a low stringency, the thresholds of SSR, SBR, and SSDR were 2.5, 1.60 and 0.80 with oligonucleotide and PCR amplicon as target templates, and 2.0, 1.60 and 0.70 with genomic DNA as target templates. Slightly higher thresholds were obtained at the high stringency condition. The thresholds of SSR and SSDR decreased with an increase in the complexity of targets (e.g., target types), and the presence of background DNA, and a decrease in the composition of targets, while SBR remained unchanged under all situations. The lowest percentage of false positives (FP) and false negatives (FN) was observed with the SSDR calculation method, suggesting that it may be a better SNR calculation for more accurate determination of SNR thresholds. Positive spots identified by SNR thresholds were verified by the Student t-test, and consistent results were observed. This study provides general guidance for users to select appropriate SNR thresholds for different samples under different hybridization conditions.

  6. Production of K?K? pairs in proton-proton collisions below the ? meson threshold

    SciTech Connect (OSTI)

    Ye, Q. J.; Hartmann, M.; Chiladze, D.; Dymov, S.; Dzyuba, A.; Gao, H.; Gebel, R.; Hejny, V.; Kacharava, A.; Lorentz, B.; Mchedlishvili, D.; Merzliakov, S.; Mielke, M.; Mikirtytchiants, S.; Ohm, H.; Papenbrock, M.; Polyanskiy, A.; Serdyuk, V.; Stein, H. J.; Ströher, H.; Trusov, S.; Valdau, Yu.; Wilkin, C.; Wüstner, P.

    2013-06-01T23:59:59.000Z

    The pp?ppK?K? reaction was measured below the ? threshold at a beam energy of 2.568 GeV using the COSY-ANKE magnetic spectrometer. By assuming that the four-body phase space is distorted only by the product of two-body final-state interactions, fits to a variety of one-dimensional distributions permit the evaluation of differential and total cross sections. The shapes of the distributions in the Kp and Kpp invariant masses are reproduced only if the K?p interaction is even stronger than that found at higher energy. The cusp effect in the K?K? distribution at the K?K¯¯¯? threshold is much more clear and some evidence is also found for coupling between the K?p and K¯¯¯?n channels. However, the energy dependence of the total cross section cannot be reproduced by considering only a simple product of such pairwise final-state interactions.

  7. Mass-Analyzed Threshold Ionization (MATI) Spectroscopy of Atoms and Molecules using VUV Synchrotron Radiation

    SciTech Connect (OSTI)

    Kostko, Oleg; Kim, Sang Kyu; Leone, Stephen R.; Ahmed, Musahid

    2009-01-28T23:59:59.000Z

    Mass-analyzed threshold ionization (MATI) spectroscopy using synchrotron radiation (Advanced Light Source, Lawrence Berkeley National Laboratory) has been performed for Ar, N2, O2, N2O, H2O, C2H2, and C6H6. MATI allows for a better determination of ionization energies compared to those derived from photoionization efficiency curves traditionally used in synchrotron photoionization mass spectrometry. The separation of the long-lived Rydberg state from the directly-formed prompt ion, essential for a meaningful MATI spectrum, has been accomplished by employing an arrangement of ion optics coupled to unique electric-field pulsing schemes. For Ar, a number of resolved bands below the ionization energy are observed, and these are ascribed to high-n,l Rydberg states prepared in the MATI scheme. The first vibrational stateresolved MATI spectra of N2 and O2 are reported and spectral characteristics are discussed in comparison with previously-reported threshold photoelectron spectroscopic studies. While MATI performed with synchrotron radiation is intrinsically less sensitive compared to laser based sources, this work demonstrates that MATI spectroscopy performed with widely tunable VUV radiation is a complementary technique for studying the ionization spectroscopy of polyatomic molecules.

  8. A precision measurement of the $p$($e,e^\\prime p\\,$)$?^0$ reaction at threshold

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chirapatpimol, Khem [UVA; et. al.,

    2015-05-01T23:59:59.000Z

    New results are reported from a measurement of $\\pi^0$ electroproduction near threshold using the $p(e,e^{\\prime} p)\\pi^0$ reaction. The experiment was designed to determine precisely the energy dependence of $s-$ and $p-$wave electromagnetic multipoles as a stringent test of the predictions of Chiral Perturbation Theory (ChPT). The data were taken with an electron beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time, complete coverage of the $\\phi^*_{\\pi}$ and $\\theta^*_{\\pi}$ angles in the $p \\pi^0$ center-of-mass was obtained for invariant energies above threshold from 0.5 MeV up to 15 MeV. The 4-momentum transfer $Q^2$ coverage ranges from 0.05 to 0.155 (GeV/c)$^2$ in fine steps. A simple phenomenological analysis of our data shows strong disagreement with $p-$wave predictions from ChPT for $Q^2>0.07$ (GeV/c)$^2$, while the $s-$wave predictions are in reasonable agreement.

  9. Production of K+K? pairs in proton-proton collisions below the ? meson threshold

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ye, Q. J.; Hartmann, M.; Chiladze, D.; Dymov, S.; Dzyuba, A.; Gao, H.; Gebel, R.; Hejny, V.; Kacharava, A.; Lorentz, B.; Mchedlishvili, D.; Merzliakov, S.; Mielke, M.; Mikirtytchiants, S.; Ohm, H.; Papenbrock, M.; Polyanskiy, A.; Serdyuk, V.; Stein, H. J.; Ströher, H.; Trusov, S.; Valdau, Yu.; Wilkin, C.; Wüstner, P.

    2013-06-01T23:59:59.000Z

    The pp?ppK+K? reaction was measured below the ? threshold at a beam energy of 2.568 GeV using the COSY-ANKE magnetic spectrometer. By assuming that the four-body phase space is distorted only by the product of two-body final-state interactions, fits to a variety of one-dimensional distributions permit the evaluation of differential and total cross sections. The shapes of the distributions in the Kp and Kpp invariant masses are reproduced only if the K?p interaction is even stronger than that found at higher energy. The cusp effect in the K+K? distribution at the K0K{bar}0 threshold is much more clear and some evidence is also found for coupling between the K?p and K?0n channels. However, the energy dependence of the total cross section cannot be reproduced by considering only a simple product of such pairwise final-state interactions.

  10. Precision Measurement of the p(e, e´p) ?? Reaction at Threshold

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chirapatpimol, K.; Shabestari, M.H.; Lindgren, R. A.; Smith, L. C.; Annand, J. R. M.; Higinbotham, D. W.; Moffit, B.

    2015-05-01T23:59:59.000Z

    New results are reported from a measurement of $\\pi^0$ electroproduction near threshold using the p(e, e´p) ?? reaction. The experiment was designed to determine precisely the energy dependence of $s-$ and $p-$wave electromagnetic multipoles as a stringent test of the predictions of Chiral Perturbation Theory (ChPT). The data were taken with an electron beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time, complete coverage of the $\\phi^*_{\\pi}$ and $\\theta^*_{\\pi}$ angles in the $p \\pi^0$ center-of-mass was obtained for invariant energies above threshold from 0.5 MeV up to 15 MeV. Themore »4-momentum transfer $Q^2$ coverage ranges from 0.05 to 0.155 (GeV/c)$^2$ in fine steps. A simple phenomenological analysis of our data shows strong disagreement with $p-$wave predictions from ChPT for $Q^2>0.07$ (GeV/c)$^2$, while the $s-$wave predictions are in reasonable agreement.« less

  11. Precision Measurement of the p ( e , e ' p ) ? 0 Reaction at Threshold

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chirapatpimol, K.; Shabestari, M.H.; Lindgren, R.A.; Smith, L.C.; Annand, J.R.M.; Higinbotham, D.W.; Moffit, B.; Nelyubin, V.; Norum, B.E.; Allada, K.; Aniol, K.; Ardashev, K.; Armstrong, D.S.; Arndt, R.A.; Benmokhtar, F.; Bernstein, A.M.; Bertozzi, W.; Briscoe, W.J.; Bimbot, L.; Camsonne, A.; Chen, J.-P.; Choi, S.; Chudakov, E.; Cisbani, E.; Cusanno, F.; Dalton, M.M.; Dutta, C.; Egiyan, K.; Fernàndez-Ramìrez, C.; Feuerbach, R.; Fissum, K.G.; Frullani, S.; Garibaldi, F.; Gayou, O.; Gilman, R.; Gilad, S.; Goity, J.; Gomez, J.; Hahn, B.; Hamilton, D.; Hansen, J.-O.; Huang, J.; Igarashi, R.; Ireland, D.; de Jager, C.W.; Jin, X.; Jiang, X.; Jinasundera, T.; Kellie, J.; Keppel, C.E.; Kolb, N.; LeRose, J.; Liyanage, N.; Livingston, K.; McNulty, D.; Mercado, L.; Michaels, R.; Mihovilovi?, M.; Qian, S.; Qian, X.; Mailyan, S.; Mamyan, V.; Marrone, S.; Monaghan, P.; Nanda, S.; Perdrisat, C.F.; Piasetzky, E.; Protopopescu, D.; Punjabi, V.; Qiang, Y.; Rachek, I.A.; Rakhman, A.; Riordan, S.; Ron, G.; Rosner, G.; Saha, A.; Sawatzky, B.; Shahinyan, A.; Širca, S.; Sparveris, N.; Subedi, R.R.; Suleiman, R.; Strakovsky, I.; Sulkosky, V.; Moinelo, J.; Voskanyan, H.; Wang, K.; Wang, Y.; Watson, J.; Watts, D.; Wojtsekhowski, B.; Workman, R.L.; Yao, H.; Zhan, X.; Zhang, Y.; Hall A Collaboration

    2015-05-01T23:59:59.000Z

    New results are reported from a measurement of ?? electroproduction near threshold using the p(e,e'p)?? reaction. The experiment was designed to determine precisely the energy dependence of s- and p-wave electromagnetic multipoles as a stringent test of the predictions of chiral perturbation theory (ChPT). The data were taken with an electron beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time, complete coverage of the ?*? and ?*? angles in the p?? center of mass was obtained for invariant energies above threshold from 0.5 up to 15 MeV. The 4-momentum transfer Q² coverage ranges from 0.05 to 0.155 (GeV/c)² in fine steps. A simple phenomenological analysis of our data shows strong disagreement with p-wave predictions from ChPT for Q²>0.07 (GeV/c)², while the s-wave predictions are in reasonable agreement.

  12. A precision measurement of the $p$($e,e^\\prime p\\,$)$?^0$ reaction at threshold

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chirapatpimol, Khem; et. al.,

    2015-05-01T23:59:59.000Z

    New results are reported from a measurement of $\\pi^0$ electroproduction near threshold using the $p(e,e^{\\prime} p)\\pi^0$ reaction. The experiment was designed to determine precisely the energy dependence of $s-$ and $p-$wave electromagnetic multipoles as a stringent test of the predictions of Chiral Perturbation Theory (ChPT). The data were taken with an electron beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time, complete coverage of the $\\phi^*_{\\pi}$ and $\\theta^*_{\\pi}$ angles in the $p \\pi^0$ center-of-mass was obtained for invariant energies above threshold from 0.5 MeV up to 15 MeV. The 4-momentummore »transfer $Q^2$ coverage ranges from 0.05 to 0.155 (GeV/c)$^2$ in fine steps. A simple phenomenological analysis of our data shows strong disagreement with $p-$wave predictions from ChPT for $Q^2>0.07$ (GeV/c)$^2$, while the $s-$wave predictions are in reasonable agreement.« less

  13. Production of K?K? pairs in proton-proton collisions below the ? meson threshold

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ye, Q. J.; Hartmann, M.; Chiladze, D.; Dymov, S.; Dzyuba, A.; Gao, H.; Gebel, R.; Hejny, V.; Kacharava, A.; Lorentz, B.; et al

    2013-06-01T23:59:59.000Z

    The pp?ppK?K? reaction was measured below the ? threshold at a beam energy of 2.568 GeV using the COSY-ANKE magnetic spectrometer. By assuming that the four-body phase space is distorted only by the product of two-body final-state interactions, fits to a variety of one-dimensional distributions permit the evaluation of differential and total cross sections. The shapes of the distributions in the Kp and Kpp invariant masses are reproduced only if the K?p interaction is even stronger than that found at higher energy. The cusp effect in the K?K? distribution at the K?K¯¯¯? threshold is much more clear and some evidencemore »is also found for coupling between the K?p and K¯¯¯?n channels. However, the energy dependence of the total cross section cannot be reproduced by considering only a simple product of such pairwise final-state interactions.« less

  14. Blister Threshold Based Thermal Limits for the U-Mo Monolithic Fuel System

    SciTech Connect (OSTI)

    D. M. Wachs; I. Glagolenko; F. J. Rice; A. B. Robinson; B. H. Rabin; M. K. Meyer

    2012-10-01T23:59:59.000Z

    Fuel failure is most commonly induced in research and test reactor fuel elements by exposure to an under-cooled or over-power condition that results in the fuel temperature exceeding a critical threshold above which blisters form on the plate. These conditions can be triggered by normal operational transients (i.e. temperature overshoots that may occur during reactor startup or power shifts) or mild upset events (e.g., pump coastdown, small blockages, mis-loading of fuel elements into higher-than-planned power positions, etc.). The rise in temperature has a number of general impacts on the state of a fuel plate that include, for example, stress relaxation in the cladding (due to differential thermal expansion), softening of the cladding, increased mobility of fission gases, and increased fission-gas pressure in pores, all of which can encourage the formation of blisters on the fuel-plate surface. These blisters consist of raised regions on the surface of fuel plates that occur when the cladding plastically deforms in response to fission-gas pressure in large pores in the fuel meat and/or mechanical buckling of the cladding over damaged regions in the fuel meat. The blister temperature threshold decreases with irradiation because the mechanical properties of the fuel plate degrade while under irradiation (due to irradiation damage and fission-product accumulation) and because the fission-gas inventory progressively increases (and, thus, so does the gas pressure in pores).

  15. The study of threshold behaviour of effective potential for $^{6}$Li+$^{58,64}$Ni systems

    E-Print Network [OSTI]

    M. Biswas; Subinit Roy; M. Sinha; M. K. Pradhan; A. Mukherjee; P. Basu; H. Majumdar; K. Ramachandran; A. Shrivastava

    2008-01-30T23:59:59.000Z

    The elastic scattering for $^6$Li+$^{64}$Ni system was measured in the bombarding energy range of 13 MeV $\\leq$ $E_{lab}$ $\\leq$ 26 MeV. A phenomenological optical model analysis was performed and the behaviour of the surface strengths of the potential components with decreasing energy was extracted. A further analysis of the measured angular distributions, along with the existing data for $^6$Li+$^{58}$Ni, was performed with two different model potentials - one with the folded potential normalized with a complex factor (OMP1) and the other with a {\\it hybrid} potential composed of a renormalized folded real and a phenomenological imaginary (OMP2) potential components - were used in the calculation. All the model potentials predict similar energy dependent behaviour for the interaction potential around the barrier. The observed energy dependence of the strengths of the real and imaginary potentials corroborate with the dispersion relation prediction for both the $^6$Li+$^{64}$Ni and $^6$Li+$^{58}$Ni systems. Though the evidence of breakup is distinct in the energy variation of the potential strengths, close to the barrier the variation is more in the line of conventional threshold anomaly. Also the threshold behaviour of the interaction potential does not indicate any distinct isotopic dependence.

  16. A precision measurement of the $p$($e,e^\\prime p\\,$)$?^0$ reaction at threshold

    E-Print Network [OSTI]

    K. Chirapatpimol; M. H. Shabestari; R. A. Lindgren; L. C. Smith; J. R. M. Annand; D. W. Higinbotham; B. Moffit; V. Nelyubin; B. E. Norum; K. Allada; K. Aniol; K. Ardashev; D. S. Armstrong; R. A. Arndt; F. Benmokhtar; A. M. Bernstein; W. Bertozzi; W. J. Briscoe; L. Bimbot; A. Camsonne; J. -P. Chen; S. Choi; E. Chudakov; E. Cisbani; F. Cusanno; M. M. Dalton; C. Dutta; K. Egiyan; C. Fernandez-Ramirez; R. Feuerbach; K. G. Fissum; S. Frullani; F. Garibaldi; O. Gayou; R. Gilman; S. Gilad; J. Goity; J. Gomez; B. Hahn; D. Hamilton; J. -O. Hansen; J. Huang; R. Igarashi; D. Ireland; C. W. de Jager; X. Jin; X. Jiang; T. Jinasundera; J. Kellie; C. E. Keppel; N. Kolb; J. LeRose; N. Liyanage; K. Livingston; D. McNulty; L. Mercado; R. Michaels; M. Mihovilovic; S. Qian; X. Qian; S. Mailyan; V. Mamyan; S. Marrone; P. Monaghan; S. Nanda; C. F. Perdrisat; E. Piasetzky; D. Protopopescu; V. Punjabi; Y. Qiang; I. A. Rachek; A. Rakhman; G. Ron; G. Rosner; A. Saha; B. Sawatzky; A. Shahinyan; S. Sirca; N. Sparveris; R. R. Subedi; R. Suleiman; I. Strakovsky; V. Sulkosky; J. Moinelo; H. Voskanyan; K. Wang; Y. Wang; J. Watson; D. Watts; B. Wojtsekhowski; R. L. Workman; H. Yao; X. Zhan; Y. Zhang

    2015-04-10T23:59:59.000Z

    New results are reported from a measurement of $\\pi^0$ electroproduction near threshold using the $p(e,e^{\\prime} p)\\pi^0$ reaction. The experiment was designed to determine precisely the energy dependence of $s-$ and $p-$wave electromagnetic multipoles as a stringent test of the predictions of Chiral Perturbation Theory (ChPT). The data were taken with an electron beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time, complete coverage of the $\\phi^*_{\\pi}$ and $\\theta^*_{\\pi}$ angles in the $p \\pi^0$ center-of-mass was obtained for invariant energies above threshold from 0.5 MeV up to 15 MeV. The 4-momentum transfer $Q^2$ coverage ranges from 0.05 to 0.155 (GeV/c)$^2$ in fine steps. A simple phenomenological analysis of our data shows strong disagreement with $p-$wave predictions from ChPT for $Q^2>0.07$ (GeV/c)$^2$, while the $s-$wave predictions are in reasonable agreement.

  17. Bound and resonance states of the dipolar anion of hydrogen cyanide: competition between threshold effects and rotation in an open quantum system

    E-Print Network [OSTI]

    K. Fossez; N. Michel; W. Nazarewicz; M. P?oszajczak; Y. Jaganathen

    2014-10-24T23:59:59.000Z

    Bound and resonance states of the dipole-bound anion of hydrogen cyanide HCN$^-$ are studied using a non-adiabatic pseudopotential method and the Berggren expansion technique involving bound states, decaying resonant states, and non-resonant scattering continuum. We devise an algorithm to identify the resonant states in the complex energy plane. To characterize spatial distributions of electronic wave functions, we introduce the body-fixed density and use it to assign families of resonant states into collective rotational bands. We find that the non-adiabatic coupling of electronic motion to molecular rotation results in a transition from the strong-coupling to weak-coupling regime. In the strong coupling limit, the electron moving in a subthreshold, spatially extended halo state follows the rotational motion of the molecule. Above the ionization threshold, electron's motion in a resonance state becomes largely decoupled from molecular rotation. Widths of resonance-band members depend primarily on the electron orbital angular momentum.

  18. ANALYTICAL METHODS FOR DISCRIMINATING STARDUST IN AEROGEL CAPTURE MEDIA

    E-Print Network [OSTI]

    Sean Brennan; Hope A. Ishii; John P. Bradley; Katharina Luening; Piero Pianetta

    Methods using X-ray fluorescence have been developed to identify cometary material captured in aerogel during the NASA Stardust mission to Comet 81P/Wild 2. These analytical methods are necessitated by the levels of trace contaminants present in the aerogel. The cometary material disaggregates during deceleration in the aerogel, so fluorescence mapping of the entire track (which can be several millimeters long) is necessary. Distinguishing those pixels which have cometary material and aerogel from those which have only cometary material can be very challenging. We have chosen a “dual thresholdmethod, with some pixels clearly having only aerogel (plus contaminants) and other pixels clearly having cometary and aerogel material. Between these two threshold levels is a set of pixels which cannot be easily ascribed to one or the other. By leaving these pixels out of the analysis, the estimate of cometary material is improved.

  19. Correlation methods

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1981-01-01T23:59:59.000Z

    Correlation methods have been developed to provide a quick and relatively simple technique for estimating the performance of passive solar systems. The correlations are done with respect to data generated from simulation models. The techniques and accuracies are described. Both the Solar Load Ratio and Un-Utilizability methods are described. The advantages and limitations of correlation methods as design tools are discussed.

  20. Ultralow threshold graded-index separate-confinement heterostructure single quantum well (Al,Ga)As lasers

    SciTech Connect (OSTI)

    Derry, P.L.; Chen, H.Z.; Morkoc, H.; Yariv, A.; Lau, K.Y.; Bar-Chaim, N.; Lee, K.; Rosenberg, J.

    1988-03-01T23:59:59.000Z

    Broad area graded-index separate-confinement heterostructure single quantum well lasers grown by molecular-beam epitaxy (MBE) with threshold current density as low as 93 A/cm/sup 2/ (520 ..mu..m long) have been fabricated. Buried lasers formed from similarly structured MBE material with liquid phase epitaxy regrowth had threshold currents at submilliampere levels when high reflectivity coatings were applied to the end facets. A cw threshold current of 0.55 mA was obtained for a laser with facet reflectivities of approx.80%, a cavity length of 120 ..mu..m, and an active region stripe width of 1 ..mu..m. These devices driven directly with logic level signals have switch-on delays <50 ps without any current prebias. Such lasers permit fully on--off switching while at the same time obviating the need for bias monitoring and feedback control.

  1. Above-threshold ionization of diatomic molecules by few-cycle laser pulses

    SciTech Connect (OSTI)

    Gazibegovic-Busuladzic, A. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Hasovic, E. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Str. 2a, D-12489 Berlin (Germany); Busuladzic, M. [Medical Faculty, University of Sarajevo, Cekalusa 90, 71000 Sarajevo (Bosnia and Herzegowina); Milosevic, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Str. 2a, D-12489 Berlin (Germany); Academy of Sciences and Arts of Bosnia and Herzegovina Bistrik 7, 71000 Sarajevo (Bosnia and Herzegowina); Kelkensberg, F.; Siu, W. K. [FOM-Institute AMOLF, Science park 104, NL-1098 XG Amsterdam (Netherlands); Vrakking, M. J. J. [Max-Born-Institut, Max-Born-Str. 2a, D-12489 Berlin (Germany); FOM-Institute AMOLF, Science park 104, NL-1098 XG Amsterdam (Netherlands); Lepine, F. [Universite Lyon 1 (France); CNRS (France); LASIM, UMR 5579, 43 bvd. du 11 novembre 1918, F-69622 Villeurbanne (France); Sansone, G.; Nisoli, M. [Politecnico di Milano, Department of Physics, National Research Council of Italy, Institute of Photonics and Nanotechnologies (CNR-IFN), Piazza L. da Vinci 32, I-20133, Milano (Italy); Znakovskaya, I. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching (Germany); Kling, M. F. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching (Germany); J.R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas 66506 (United States)

    2011-10-15T23:59:59.000Z

    Above-threshold ionization of diatomic molecules by infrared carrier-envelope phase (CEP) stable few-cycle laser pulses is analyzed both experimentally and theoretically. The theoretical approach is based on the recently developed molecular improved strong-field approximation (ISFA), generalized to few-cycle pulses. Instead of using the first Born approximation, the rescattering matrix element in the ISFA is now calculated exactly. This modification leads to the appearance of characteristic minima in the differential cross section as a function of the scattering angle. Experimental angle-resolved photoelectron spectra of N{sub 2} and O{sub 2} molecules are obtained using the velocity map imaging technique. A relatively good agreement of experimental and simulated angle-resolved spectra, CEP-dependent asymmetry maps, and extracted electron-molecular ion elastic scattering differential cross sections is obtained.

  2. Uncertainties of optical-model parameters for the study of the threshold anomaly

    E-Print Network [OSTI]

    Daniel Abriola; A. Arazi; J. Testoni; F. Gollan; G. V. Martí

    2015-03-13T23:59:59.000Z

    In the analysis of elastic-scattering experimental data, optical-model parameters (usually, depths of real and imaginary potentials) are fitted and conclusions are drawn analyzing their variations at bombardment energies close to the Coulomb barrier (threshold anomaly). The judgement about the shape of this variation (related to the physical processes producing this anomaly) depends on these fitted values but the robustness of the conclusions strongly depends on the uncertainties with which these parameters are derived. We will show that previous published studies have not used a common criterium for the evaluation of the parameter uncertainties. In this work, a study of these uncertainties is presented, using conventional statistic tools as well as bootstrapping techniques. As case studies, these procedures are applied to re-analyze detailed elastic-scattering data for the $^{12}$C + $^{208}$Pb and the $^6$Li + $^{80}$Se systems.

  3. Violations of Lorentz invariance in the neutrino sector: an improved analysis of anomalous threshold constraints

    E-Print Network [OSTI]

    Luca Maccione; Stefano Liberati; David M. Mattingly

    2013-03-11T23:59:59.000Z

    Recently there has been a renewed activity in the physics of violations of Lorentz invariance in the neutrino sector. Flavor dependent Lorentz violation, which generically changes the pattern of neutrino oscillations, is extremely tightly constrained by oscillation experiments. Flavor independent Lorentz violation, which does not introduce new oscillation phenomena, is much more weakly constrained with constraints coming from time of flight and anomalous threshold analyses. We use a simplified rotationally invariant model to investigate the effects of finite baselines and energy dependent dispersion on anomalous reaction rates in long baseline experiments and show numerically that anomalous reactions do not necessarily cut off the spectrum quite as sharply as currently assumed. We also present a revised analysis of how anomalous reactions can be used to cast constraints from the observed atmospheric high energy neutrinos and the expected cosmogenic ones.

  4. Attosecond electron pulses from interference of above-threshold de Broglie waves

    E-Print Network [OSTI]

    Sandor Varro; Gyozo Farkas

    2007-05-02T23:59:59.000Z

    It is shown that the the interference of above-threshold electron de Broglie waves, generated by an intense laser pulse at a metal surface yields attosecond electron pulses. This inerference is an analogon of the superposition of high harmonics generated from rare gas atoms, resulting in trains of attosecond light pulses.Owing to the inherent kinematic dispersion, the propagation of attosecond de Broglie waves in vacuum is very different from that of attosecond light pulses, which propagate without changing shape. Above the metal surface there are "collaps bands" and "revival layers" of the electron current even at macroscopic distances. In the range of parameters considered, the maximum value of the current densities of such ultrashort electron pulses has been estimated to be of order of couple of tenths of milliamps per square centimeters.

  5. Rescattering Effect and Near Threshold Enhancement of $p\\bar p$ System

    E-Print Network [OSTI]

    G. Y. Chen; H. R. Dong; J. P. Ma

    2008-06-28T23:59:59.000Z

    We study the observed enhancement of a $p\\bar p$ system near the threshold in the process $J/\\psi \\to \\gamma p\\bar p$ and $e^+ e^- \\to p\\bar p$. From early studies the enhancement can be explained by final state interactions, which are in general taken into account with some potential models. In this work we offer a simple approach within quantum field theory to explain the observed enhancement. We point out that among different final state interactions the rescattering in a $N\\bar N$ system though exchange of $\\pi$ is the most important. The effects of the rescattering is completely fixed by the well-known coupling $g_{\\pi NN}$. Our results show that the enhancement in $J/\\psi \\to \\gamma p\\bar p$ and $e^+ e^- \\to p\\bar p$ can be well described with the rescattering effects.

  6. Study of a Threshold Cherenkov Counter Based on Silica Aerogels with Low Refractive Indices ?

    E-Print Network [OSTI]

    I. Adachi; T. Sumiyoshi; K. Hayashi; N. Iida; R. Enomoto; K. Tsukada; R. Suda; S. Matsumoto; K. Natori; M. Yokoyama; H. Yokogawa

    1994-01-01T23:59:59.000Z

    To identify ? ± and K ± in the region of 1.0 ? 2.5 GeV/c, a threshold Cherenkov counter equipped with silica aerogels has been investigated. Silica aerogels with a low refractive index of 1.013 have been successfully produced using a new technique. By making use of these aerogels as radiators, we have constructed a Cherenkov counter and have checked its properties in a test beam. The obtained results have demonstrated that our aerogel was transparent enough to make up for loss of the Cherenkov photon yield due to a low refractive index. Various configurations for the photon collection system and some types of photomultipliers, such as the fine-mesh type, for a read out were also tested. From these studies, our design of a Cherenkov counter dedicated to ?/K separation up to a few GeV/c with an efficiency greater than 90 % was considered. 1

  7. Influence of cleaning process on the laser-induced damage threshold of substrates

    SciTech Connect (OSTI)

    Shen Zhengxiang; Ding Tao; Ye Xiaowen; Wang Xiaodong; Ma Bin; Cheng Xinbin; Liu Huasong; Ji Yiqin; Wang Zhanshan

    2011-03-20T23:59:59.000Z

    The cleaning process of optical substrates plays an important role during the manufacture of high-power laser coatings. Two kinds of substrates, fused silica and BK7 glass, and two cleaning processes, called process 1 and process 2 having different surfactant solutions and different ultrasonic cleaning parameters, are adopted to compare the influence of the ultrasonic cleaning technique on the substrates. The evaluation standards of the cleaning results include contaminant-removal efficiency, weak absorption, and laser-induced damage threshold of the substrates. For both fused silica and BK7, process 2 is more efficient than process 1. Because acid and alkaline solutions can increase the roughness of BK7, process 2 is unsuitable for BK7 glass cleaning. The parameters of the cleaning protocol should be changed depending on the material of the optical components and the type of contamination.

  8. Ablation experiment and threshold calculation of titanium alloy irradiated by ultra-fast pulse laser

    SciTech Connect (OSTI)

    Zheng, Buxiang; Jiang, Gedong; Wang, Wenjun, E-mail: wenjunwang@mail.xjtu.edu.cn; Wang, Kedian; Mei, Xuesong [School of Mechanical Engineering, Xi'an Jiaotong University, No. 28, Xianning Westroad, Xi'an 710049 (China) [School of Mechanical Engineering, Xi'an Jiaotong University, No. 28, Xianning Westroad, Xi'an 710049 (China); State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710054 (China)

    2014-03-15T23:59:59.000Z

    The interaction between an ultra-fast pulse laser and a material's surface has become a research hotspot in recent years. Micromachining of titanium alloy with an ultra-fast pulse laser is a very important research direction, and it has very important theoretical significance and application value in investigating the ablation threshold of titanium alloy irradiated by ultra-fast pulse lasers. Irradiated by a picosecond pulse laser with wavelengths of 1064 nm and 532 nm, the surface morphology and feature sizes, including ablation crater width (i.e. diameter), ablation depth, ablation area, ablation volume, single pulse ablation rate, and so forth, of the titanium alloy were studied, and their ablation distributions were obtained. The experimental results show that titanium alloy irradiated by a picosecond pulse infrared laser with a 1064 nm wavelength has better ablation morphology than that of the green picosecond pulse laser with a 532 nm wavelength. The feature sizes are approximately linearly dependent on the laser pulse energy density at low energy density and the monotonic increase in laser pulse energy density. With the increase in energy density, the ablation feature sizes are increased. The rate of increase in the feature sizes slows down gradually once the energy density reaches a certain value, and gradually saturated trends occur at a relatively high energy density. Based on the linear relation between the laser pulse energy density and the crater area of the titanium alloy surface, and the Gaussian distribution of the laser intensity on the cross section, the ablation threshold of titanium alloy irradiated by an ultra-fast pulse laser was calculated to be about 0.109 J/cm{sup 2}.

  9. Method for microbeam radiation therapy

    DOE Patents [OSTI]

    Slatkin, D.N.; Dilmanian, F.A.; Spanne, P.O.

    1994-08-16T23:59:59.000Z

    A method is disclosed of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation. The dose is in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue. No Drawings

  10. Threshold-Resummed Cross Section for the Drell-Yan Process in Pion-Nucleon Collisions at COMPASS

    E-Print Network [OSTI]

    Matthias Aicher; Andreas Schäfer; Werner Vogelsang

    2011-04-18T23:59:59.000Z

    We present a study of the Drell-Yan process in pion-proton collisions including next-to-leading-logarithmic threshold-resummed contributions. We analyze rapidity-integrated as well as rapidity-differential cross sections in the kinematic regime relevant for the COMPASS fixed target experiment. We find that resummation leads to a significant enhancement of the cross section compared to fixed-order calculations in this regime. Particularly large corrections arise at large forward and backward rapidities of the lepton pair. We also study the scale dependence of the cross section and find it to be substantially reduced by threshold resummation.

  11. Vortex methods

    SciTech Connect (OSTI)

    Chorin, A.J. [California Univ., Berkeley, CA (United States). Dept. of Mathematics]|[Lawrence Berkeley Lab., CA (United States)

    1993-06-01T23:59:59.000Z

    Vortex methods originated from the observation that in incompressible inviscid flow vorticity (or, more accurately, circulation) is a conserved quantity, as can be readily deduced from the absence of tangential stresses. Thus, if the vorticity is known at time t=0, one can find the flow at a later time by simply following the vorticity. In this narrow context, a vortex method is a numerical method that follows vorticity. The author restricts himself in these lectures to a special class of numerical vortex methods, those that are based on a Lagrangian transport of vorticity in hydrodynamics by smoothed particles (blobs) and those whose analysis contributes to the understanding of blob methods. Blob methods started in the 1930`s.

  12. Connection method

    DOE Patents [OSTI]

    Weyand, J.D.

    1986-11-18T23:59:59.000Z

    A method is disclosed of making a region exhibiting a range of compositions, comprising plasma spraying various compositions on top of one another onto a base. 2 figs.

  13. Method to improve reliability of a fuel cell system using low performance cell detection at low power operation

    DOE Patents [OSTI]

    Choi, Tayoung; Ganapathy, Sriram; Jung, Jaehak; Savage, David R.; Lakshmanan, Balasubramanian; Vecasey, Pamela M.

    2013-04-16T23:59:59.000Z

    A system and method for detecting a low performing cell in a fuel cell stack using measured cell voltages. The method includes determining that the fuel cell stack is running, the stack coolant temperature is above a certain temperature and the stack current density is within a relatively low power range. The method further includes calculating the average cell voltage, and determining whether the difference between the average cell voltage and the minimum cell voltage is greater than a predetermined threshold. If the difference between the average cell voltage and the minimum cell voltage is greater than the predetermined threshold and the minimum cell voltage is less than another predetermined threshold, then the method increments a low performing cell timer. A ratio of the low performing cell timer and a system run timer is calculated to identify a low performing cell.

  14. The vibrational energies of ozone up to the dissociation threshold: Dynamics calculations on an accurate potential energy surface

    E-Print Network [OSTI]

    Farantos, Stavros C.

    The vibrational energies of ozone up to the dissociation threshold: Dynamics calculations present an ab initio potential energy surface for the ground electronic state of ozone. It is global, i. All bound states of nonrotating ozone up to more than 99% of the dissociation energy are calculated

  15. Damage Threshold of Platinum Coating used for Optics for Self-Seeding of Soft X-ray Free Electron Laser

    SciTech Connect (OSTI)

    Krzywinski, Jacek; Cocco, Daniele; Moeller, Stefan; Ratner, Daniel

    2015-01-01T23:59:59.000Z

    We investigated the experimental damage threshold of platinum coating on a silicon substrate illuminated by soft x-ray radiation at grazing incidence angle of 2.1 deg. The coating was the same as the blazed grating used for the soft X-ray self-seeding optics of the Linac Coherent Light Source free electron laser. The irradiation condition was chosen such that the absorbed dose was similar to the maximum dose expected for the grating. The expected dose was simulated by solving the Helmholtz equation in non-homogenous media. The experiment was performed at 900 eV photon energy for both single pulse and multi-shot conditions. We have not observed single shot damage. This corresponds to a single shot damage threshold being higher than 3 J/cm2. The multiple shot damage threshold measured for 10 shots and about 600 shots was determined to be 0.95 J/cm2 and 0.75 J/cm2 respectively. The damage threshold occurred at an instantaneous dose which is higher that the melt dose of platinum.

  16. Damage Threshold of Platinum Coating used for Optics for Self-Seeding of Soft X-ray Free Electron Laser

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Krzywinski, Jacek; Cocco, Daniele; Moeller, Stefan; Ratner, Daniel

    2015-01-01T23:59:59.000Z

    We investigated the experimental damage threshold of platinum coating on a silicon substrate illuminated by soft x-ray radiation at grazing incidence angle of 2.1 deg. The coating was the same as the blazed grating used for the soft X-ray self-seeding optics of the Linac Coherent Light Source free electron laser. The irradiation condition was chosen such that the absorbed dose was similar to the maximum dose expected for the grating. The expected dose was simulated by solving the Helmholtz equation in non-homogenous media. The experiment was performed at 900 eV photon energy for both single pulse and multi-shot conditions. Wemore »have not observed single shot damage. This corresponds to a single shot damage threshold being higher than 3 J/cm2. The multiple shot damage threshold measured for 10 shots and about 600 shots was determined to be 0.95 J/cm2 and 0.75 J/cm2 respectively. The damage threshold occurred at an instantaneous dose which is higher that the melt dose of platinum.« less

  17. Low-threshold, mirrorless emission at 981 nm in an Yb,Gd,Lu:KYW inverted rib waveguide laser

    E-Print Network [OSTI]

    Low-threshold, mirrorless emission at 981 nm in an Yb,Gd,Lu:KYW inverted rib waveguide laser Amol for generating short pulses [2]. Liquid phase epitaxy has been used to fabricate planar [3, 4] and channel [5, 6W and a channel waveguide laser with an output power of 11 mW [9]. In this paper we demonstrate mirrorless lasing

  18. Threshold Pressure for Disappearance of Size-Induced Effect in Spinel-Structure Ge3N4 Nanocrystals

    E-Print Network [OSTI]

    Downs, Robert T.

    Threshold Pressure for Disappearance of Size-Induced Effect in Spinel-Structure Ge3N4 Nanocrystals demonstrate that the incompressibility of spinel Ge3N4 nanocrystals decreases when the pressure is elevated above 20 GPa. Ge3N4 nanocrystals initially exhibit a higher bulk modulus of 381(2) GPa. But, above 20

  19. A Thermally-Aware Methodology for Design-Specific Optimization of Supply and Threshold Voltages in Nanometer Scale ICs

    E-Print Network [OSTI]

    411 A Thermally-Aware Methodology for Design-Specific Optimization of Supply and Threshold Voltages and associated thermal effects have strong impact on the packaging, cooling costs, and reliability for deep submicron technologies [2-5]. For power-constrained applications, lowering supply voltage (Vdd) offers

  20. A peaks-over-threshold analysis of extreme traffic load effects on bridges Franziska Schmidt, Xiao Yi Zhou, Franois Toutlemonde

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    extreme traffic load or traffic load effect. These are: i. a half-normal curve fitted to the end1 A peaks-over-threshold analysis of extreme traffic load effects on bridges Franziska Schmidt focuses on modeling and estimating tail parameters of bridge traffic load effects by generalized Pareto

  1. Comparison of near-threshold reactivity of ground-state and spin-orbit excited chlorine atoms with methane

    E-Print Network [OSTI]

    Zare, Richard N.

    indicate that the Cl* CH4 reaction is unimportant in the near-threshold collision energy range of 0 at both low and high temperatures. Among other possible sources for this behavior, Ravishankara and Wine3. This postulate is based on the assump- tion that the extra spin-orbit energy 881 cm 1 of Cl* is available

  2. Oxygen and organic matter thresholds for benthic faunal activity on the Pakistan margin oxygen minimum zone (7001100 m)

    E-Print Network [OSTI]

    Levin, Lisa

    Oxygen and organic matter thresholds for benthic faunal activity on the Pakistan margin oxygen increased animal activity associated with increasing bottom-water oxygen concentration. We examined faunal community responses to oxygen and organic matter gradients across the lower oxygen minimum zone (OMZ

  3. Observation of a stripping threshold for the reaction N2 ^++CH4?N2H^++CH3

    E-Print Network [OSTI]

    Wyatt, J. R.; Strattan, L. W.; Snyder, S. C.; Hierl, Peter M.

    1976-01-01T23:59:59.000Z

    to possess a threshold at 0.1 eV. At the higher energies there is a large isotope effect favoring abstraction of H over D. The product velocity vector distribution is strongly peaked forward of the center of mass, indicating that the reaction is predominantly...

  4. Error Probabilities and Threshold Selection in Networked Nuclear Detection Chetan D. Pahlajani, Jianxin Sun, Ioannis Poulakakis, Herbert G. Tanner

    E-Print Network [OSTI]

    Poulakakis, Ioannis

    of nuclear detection relates to the problem of using radiation sensor data to decide, within a given time. Specifically, it is noted that currently deployed systems for detecting the transport of illicit radioactiveError Probabilities and Threshold Selection in Networked Nuclear Detection Chetan D. Pahlajani

  5. Vacuum ultraviolet mass-analyzed threshold ionization spectroscopy of benzene: Vibrational analysis of C6H6

    E-Print Network [OSTI]

    Kim, Myung Soo

    Vacuum ultraviolet mass-analyzed threshold ionization spectroscopy of benzene: Vibrational analysis-photon spectra agrees with the previous suggestion that the geometry of benzene cation in the ground electronic. INTRODUCTION Benzene cation has been the focus of an intensive re- search effort, both experimental1

  6. Damage Threshold of Platinum Coating used for Optics for Self-Seeding of Soft X-ray Free Electron Laser

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Krzywinski, Jacek; Cocco, Daniele; Moeller, Stefan; Ratner, Daniel

    2015-01-01T23:59:59.000Z

    We investigated the experimental damage threshold of platinum coating on a silicon substrate illuminated by soft x-ray radiation at grazing incidence angle of 2.1 deg. The coating was the same as the blazed grating used for the soft X-ray self-seeding optics of the Linac Coherent Light Source free electron laser. The irradiation condition was chosen such that the absorbed dose was similar to the maximum dose expected for the grating. The expected dose was simulated by solving the Helmholtz equation in non-homogenous media. The experiment was performed at 900 eV photon energy for both single pulse and multi-shot conditions. We have not observed single shot damage. This corresponds to a single shot damage threshold being higher than 3 J/cm2. The multiple shot damage threshold measured for 10 shots and about 600 shots was determined to be 0.95 J/cm2 and 0.75 J/cm2 respectively. The damage threshold occurred at an instantaneous dose which is higher that the melt dose of platinum.

  7. Damage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength

    E-Print Network [OSTI]

    von der Linde, D.

    to the optical components required to utilize XFEL beams, including radiation damage. Theoretical workDamage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength SC were exposed to single 25 fs long pulses of 32.5 nm free-electron-laser radiation at fluences of up

  8. Robust model-based detection of the lung field boundaries in portable chest radiographs supported by selective thresholding

    E-Print Network [OSTI]

    Athens, University of

    Robust model-based detection of the lung field boundaries in portable chest radiographs supported of the lung field boundaries in portable chest radiographs supported by selective thresholding D K Iakovidis1-ray misinterpretation rates. This paper presents a novel methodology for the detection of the lung field boundaries

  9. Stack Sizing Analysis and Optimization for FinFET Logic Cells and Circuits Operating in the Sub/Near-Threshold Regime

    E-Print Network [OSTI]

    Pedram, Massoud

    -threshold regimes. This model accurately captures the drain current as a function of both the gate and drain-inversion region [10]. The drain current of a FinFET transistor in the super-threshold region follows the -power. Unfortunately, the EKV model is difficult to provide back- of-the-envelope insights and is difficult to work

  10. Does Beta React to Market Conditions?: Estimates of Bull and Bear Betas using a Nonlinear Market Model with Endogenous Threshold Parameter

    E-Print Network [OSTI]

    Kearns, Michael

    Does Beta React to Market Conditions?: Estimates of Bull and Bear Betas using a Nonlinear Market Model with Endogenous Threshold Parameter by George Woodward and Heather Anderson Department transition between bull and bear states and allows the data to determine the threshold value. The estimated

  11. IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY, VOL. 7, NO. 1, MARCH 2007 181 Impact of Strain or Ge Content on the Threshold

    E-Print Network [OSTI]

    Kumar, M. Jagadesh

    of Strain or Ge Content on the Threshold Voltage of Nanoscale Strained-Si/SiGe Bulk MOSFETs M. Jagadesh--The impact of strain on the threshold voltage of nanoscale strained-Si/SiGe MOSFETs is studied by developing a compact analytical model. Our model includes the effects of strain (Ge mole fraction in SiGe substrate

  12. One-Photon Mass-Analyzed Threshold Ionization Spectroscopy of Bis(6-benzene)chromium and Its Benzene and Ar Clusters

    E-Print Network [OSTI]

    Kim, Sang Kyu

    One-Photon Mass-Analyzed Threshold Ionization Spectroscopy of Bis(6-benzene)chromium and Its Benzene and Ar Clusters Kyo-Won Choi and Sang Kyu Kim* Department of Chemistry and School of Molecular-analyzed threshold ionization (MATI) spectroscopy of bis(6-benzene)chromium is reported. The adiabatic ionization

  13. STAR FORMATION LAWS AND THRESHOLDS FROM INTERSTELLAR MEDIUM STRUCTURE AND TURBULENCE

    SciTech Connect (OSTI)

    Renaud, Florent; Kraljic, Katarina; Bournaud, Frederic, E-mail: florent.renaud@cea.fr [Laboratoire AIM Paris-Saclay, CEA/IRFU/SAp, Universite Paris Diderot, F-91191 Gif-sur-Yvette Cedex (France)

    2012-11-20T23:59:59.000Z

    We present an analytical model of the relation between the surface density of gas and star formation rate in galaxies and clouds, as a function of the presence of supersonic turbulence and the associated structure of the interstellar medium (ISM). The model predicts a power-law relation of index 3/2, flattened under the effects of stellar feedback at high densities or in very turbulent media, and a break at low surface densities when ISM turbulence becomes too weak to induce strong compression. This model explains the diversity of star formation laws and thresholds observed in nearby spirals and their resolved regions, the Small Magellanic Cloud, high-redshift disks and starbursting mergers, as well as Galactic molecular clouds. While other models have proposed interstellar dust content and molecule formation to be key ingredients to the observed variations of the star formation efficiency, we demonstrate instead that these variations can be explained by ISM turbulence and structure in various types of galaxies.

  14. Experimental onset threshold and magnetic pressure pileup for 3D Sweet-Parker reconnection

    SciTech Connect (OSTI)

    Intrator, Thomas P [Los Alamos National Laboratory; Sun, Xuan [Los Alamos National Laboratory; Lapenta, Giovanni [Los Alamos National Laboratory; Furno, Ivo [Los Alamos National Laboratory; [NON LANL

    2008-01-01T23:59:59.000Z

    In space, astrophysical and laboratory plasmas, magnetic reconnect ion converts magnetic into particle energy during unsteady, explosive events. The abrupt onset and cessation has been a long standing puzzle. We show the first three-dimensional (3D) laboratory example of onset and stagnation of Sweet-Parker type magnetic reconnection between magnetized and parallel current (flux) ropes driven by magnetohydrodynamic (MHD) attraction and 3D instability. Mutually attracting flux ropes advect and merge oppositely directed magnetic fields. Magnetic flux is annihilated, but reaches soon a threshold where magnetic flux and pressure pile up, and reconnection magnetic topology appears. This occurs when inflow speeds exceed the SweetParker speed v{sub SP} = v{sub A} / S{sup 1/2}, where v{sub A} is the Alfven speed and S is the Lundquist number for the reconnection layer, as magnetic flux arrives faster than flux annihilation can process it. Finally piled up fields generate MHD reaction forces that stall the inflow and the reconnection process.

  15. Phase space path-integral formulation of the above-threshold ionization

    SciTech Connect (OSTI)

    Milosevic, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina) [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Str. 2a, 12489 Berlin (Germany); Academy of Sciences and Arts of Bosnia and Herzegovina, Bistrik 7, 71000 Sarajevo (Bosnia and Herzegowina)

    2013-04-15T23:59:59.000Z

    Atoms and molecules submitted to a strong laser field can emit electrons of high energies in the above-threshold ionization (ATI) process. This process finds a highly intuitive and also quantitative explanation in terms of Feynman's path integral and the concept of quantum orbits [P. Salieres et al., Science 292, 902 (2001)]. However, the connection with the Feynman path-integral formalism is explained only by intuition and analogy and within the so-called strong-field approximation (SFA). Using the phase space path-integral formalism we have obtained an exact result for the momentum-space matrix element of the total time-evolution operator. Applying this result to the ATI we show that the SFA and the so-called improved SFA are, respectively, the zeroth- and the first-order terms of the expansion in powers of the laser-free effective interaction of the electron with the rest of the atom (molecule). We have also presented the second-order term of this expansion which is responsible for the ATI with double scattering of the ionized electron.

  16. Observation of abnormally large radii of nuclei in excited states in the vicinity of neutron thresholds

    SciTech Connect (OSTI)

    Ogloblin, A. A., E-mail: ogloblina@bk.ru; Danilov, A. N. [Russian Research Centre Kurchatov Institute (Russian Federation); Belyaeva, T. L. [Universidad Nacional Autonoma de Mexico (UNAM) (Mexico); Demyanova, A. S. [Russian Research Centre Kurchatov Institute (Russian Federation); Goncharov, S. A. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation); Trzaska, W. [University of Jyvaeskylae (Finland)

    2011-11-15T23:59:59.000Z

    Differential cross sections for inelastic scattering leading to the excitation of some nuclear states situated near neutron-emission thresholds were analyzed. With the aid of a modified diffraction model, abnormally large radii were found for the 1/2{sub 1}{sup +} state of the {sup 13}C nucleus at 3.09 MeV, for the first levels of positive-parity rotational bands in the {sup 9}Be (1/2{sup +} level at 1.68 MeV and 5/2{sup +} level at 3.05 MeV) and {sup 11}Be (5/2{sup +} level at 1.78 MeV and 3/2{sup +} level at 3.41 MeV) nuclei, and for the 2{sub 1}{sup +} state of the {sup 14}Be nucleus at 1.54 MeV and 1{sub 1}{sup -} state of the {sup 12}Be nucleus at 2.7 MeV. All of these states possess signatures typical of neutron halos.

  17. A Threshold Gas \\v{C}erenkov Detector for the Spin Asymmetries of the Nucleon Experiment

    E-Print Network [OSTI]

    Armstrong, Whitney R; Kaczanowicz, Ed; Lukhanin, Alexander; Meziani, Zein-Eddine; Sawatzky, Brad

    2015-01-01T23:59:59.000Z

    We report on the design, construction, commissioning, and performance of a threshold gas \\v{C}erenkov counter in an open configuration, which operates in a high luminosity environment and produces a high photo-electron yield. Part of a unique open geometry detector package known as the Big Electron Telescope Array, this \\v{C}erenkov counter served to identify scattered electrons and reject produced pions in an inclusive scattering experiment known as the Spin Asymmetries of the Nucleon Experiment E07-003 at the Thomas Jefferson National Accelerator Facility (TJNAF) also known as Jefferson Lab. The experiment consisted of a measurement of double spin asymmetries $A_{\\parallel}$ and $A_{\\perp}$ of a polarized electron beam impinging on a polarized ammonia target. The \\v{C}erenkov counter's performance is characterised by a yield of about 20 photoelectrons per electron or positron track. Thanks to this large number of photoelectrons per track, the \\v{C}erenkov counter had enough resolution to identify electron-p...

  18. High-order above-threshold ionization of argon: Plateau resonances and the Floquet quasienergy spectrum

    SciTech Connect (OSTI)

    Potvliege, R. M.; Vucic, Svetlana [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Institute of Physics, Pregrevica 118, 11080 Belgrade-Zemun (Serbia and Montenegro)

    2006-08-15T23:59:59.000Z

    The Floquet quasienergy spectrum of argon in a strong laser field of 800 nm wavelength is calculated for intensities up to 7x10{sup 13} W cm{sup -2}, and beyond for some states, using a discrete complex basis set. Many of the dressed excited states of interest shift nonponderomotively in complicated ways but keep an ionization width narrow enough to produce sharp enhancements of above-threshold ionization (ATI) through Stark-shift-induced resonances. The quasienergy map is compared to high-resolution ATI spectra for 120 fs Ti:sapphire pulses [Nandor et al., Phys. Rev. A 60, R1771 (1999)]. The plateau enhancements happen at intensities where the dressed ground state is in resonance or in the wing of resonances with dressed excited states. The resonant dressed states are identified. In many cases, the same state is responsible for an enhancement of ATI in the low as well as the high orders. No evidence is found for enhancements that are not concomitant with any curve crossing and could thereby be interpreted as channel-closing enhancement.

  19. Investigation of the passivity, hydrogen embrittlement and threshold stress of duplex stainless steel

    SciTech Connect (OSTI)

    Gojic, M.; Metikos-Hukovic, M.; Babic, R. [Univ. of Zagreb (Croatia)

    1996-12-31T23:59:59.000Z

    The electrochemical behavior of duplex stainless steel has been studied in various environments. Its passivity state was investigated in borate-buffer using cyclic voltammetry and impedance spectroscopy techniques. The susceptibility towards sulfide stress cracking and hydrogen embrittlement were tested at a constant load under cathodic polarization in the NACE solution saturated with H{sub 2}S and 0.5 M sulfuric acid solution containing As{sub 2}O{sub 3} as a promoter. SEM analysis accompanied these investigations. It is proposed that the highly protective quality of the passive film formed on the investigated duplex stainless steel may be associated with the presence of multiple oxidation rates (Cr{sup 3+} and Cr{sup 6+}) formed in the solid state along with (CrO{sub 4}{sup 2{minus}} and MoO{sub 4}{sup 2{minus}}) anions and the great variety of possible bridging ligand states (OH{sup {minus}}, H{sub 2}O, O{sup 2{minus}}). This leads to a significant degree of bonding flexibility and supports amorphous, i.e., glassy structure of the passive film. Therefore, the stresses that would be associated with epitaxy, are easily alleviated without the creation of long-range defect structures. The investigated duplex stainless steel shows high resistance to hydrogen embrittlement and sulfide stress cracking. The embrittlement index was determined to be 26%, while the threshold stress amounts to 84% of the yield strength.

  20. No-Impact Threshold Values for NRAP’s Reduced Order Models

    SciTech Connect (OSTI)

    Last, George V.; Murray, Christopher J.; Brown, Christopher F.; Jordan, Preston D.; Sharma, Maneesh

    2013-02-01T23:59:59.000Z

    The purpose of this study was to develop methodologies for establishing baseline datasets and statistical protocols for determining statistically significant changes between background concentrations and predicted concentrations that would be used to represent a contamination plume in the Gen II models being developed by NRAP’s Groundwater Protection team. The initial effort examined selected portions of two aquifer systems; the urban shallow-unconfined aquifer system of the Edwards-Trinity Aquifer System (being used to develop the ROM for carbon-rock aquifers, and the a portion of the High Plains Aquifer (an unconsolidated and semi-consolidated sand and gravel aquifer, being used to development the ROM for sandstone aquifers). Threshold values were determined for Cd, Pb, As, pH, and TDS that could be used to identify contamination due to predicted impacts from carbon sequestration storage reservoirs, based on recommendations found in the EPA’s “Unified Guidance for Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities” (US Environmental Protection Agency 2009). Results from this effort can be used to inform a “no change” scenario with respect to groundwater impacts, rather than the use of an MCL that could be significantly higher than existing concentrations in the aquifer.

  1. Study of the near-threshold ? ? mass enhancement in doubly OZI-suppressed J / ? ? ? ? ? decays

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ablikim, M.; Achasov, M. N.; Albayrak, O.; Ambrose, D. J.; An, F. F.; An, Q.; Bai, J. Z.; Ban, Y.; Becker, J.; Bennett, J. V.; Bertani, M.; Bian, J. M.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; Ding, W. M.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fang, J.; Fang, S. S.; Fava, L.; Feng, C. Q.; Ferroli, R. B.; Friedel, P.; Fu, C. D.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, T.; Guo, Y. P.; Han, Y. L.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Huang, G. M.; Huang, G. S.; Huang, J. S.; Huang, L.; Huang, X. T.; Huang, Y.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Kopf, B.; Kornicer, M.; Kuehn, W.; Lai, W.; Lange, J. S.; Leyhe, M.; Li, C. H.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, K.; Li, Lei; Li, Q. J.; Li, S. L.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Liao, X. T.; Lin, D.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H.; Liu, H. B.; Liu, H. H.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K.; Liu, K. Y.; Liu, Kai; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X. Y.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nicholson, C.; Nikolaev, I. B.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Park, J. W.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Prencipe, E.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, X. S.; Qin, Y.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schaefer, B. D.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Toth, D.; Ullrich, M.; Varner, G. S.; Wang, B. Q.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q. J.; Wang, S. G.; Wang, X. F.; Wang, X. L.; Wang, Y. F.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, Q. G.; Wen, S. P.; Werner, M.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, S. X.; Wu, W.; Wu, Z.; Xia, L. G.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, G. M.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Xu, Z. R.; Xue, F.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, H. W.; Yu, J. S.; Yu, S. P.; Yuan, C. Z.; Yuan, Y.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, R.; Zhang, S. H.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhang, Zhenghao; Zhao, G.; Zhao, H. S.; Zhao, J. W.; Zhao, K. X.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. Z.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zhong, B.; Zhong, Z.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. M.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.

    2013-02-01T23:59:59.000Z

    A 2.25×10? J/? event sample accumulated with the BESIII detector is used to study the doubly Okubo-Zweig-Iizuka-suppressed decay modes J/?????, ????????, ??K?K?. A strong deviation (>30?) from three-body J/????? phase space is observed near the ?? mass threshold that is consistent with a previous observation reported by the BESII experiment. A partial wave analysis with a tensor covariant amplitude that assumes that the enhancement is due to the presence of a resonance, the X(1810), is performed and confirms that the spin-parity of the X(1810) is 0??. The mass and width of the X(1810) are determined to be M=1795±7(stat)+13-5(syst)±19(mod) MeV/c² and ?=95±10(stat)+21-34(syst)±75(mod) MeV/c², respectively, and the product branching fraction is measured to be B(J/???X(1810))×B(X(1810)???)=(2.00±0.08(stat)+0.45-1.00(syst)±1.30(mod))×10??. These results are consistent within errors with those of the BESII experiment.

  2. Study of a Threshold Cherenkov Counter Based on Silica Aerogels with Low Refractive Indices

    E-Print Network [OSTI]

    I. Adachi et al

    1994-12-13T23:59:59.000Z

    To identify $\\pi^{\\pm}$ and $K^{\\pm}$ in the region of $1.0\\sim 2.5$ GeV/c, a threshold Cherenkov counter equipped with silica aerogels has been investigated. Silica aerogels with a low refractive index of 1.013 have been successfully produced using a new technique. By making use of these aerogels as radiators, we have constructed a Cherenkov counter and have checked its properties in a test beam. The obtained results have demonstrated that our aerogel was transparent enough to make up for loss of the Cherenkov photon yield due to a low refractive index. Various configurations for the photon collection system and some types of photomultipliers, such as the fine-mesh type, for a read out were also tested. From these studies, our design of a Cherenkov counter dedicated to $\\pi / K$ separation up to a few GeV/c %in the momentum range of $1.0 \\sim 2.5$ GeV/c with an efficiency greater than $90$ \\% was considered.

  3. Maximum approximate entropy and r threshold: A new approach for regularity changes detection

    E-Print Network [OSTI]

    Juan F. Restrepo; Gastón Schlotthauer; María E. Torres

    2014-05-29T23:59:59.000Z

    Approximate entropy (ApEn) has been widely used as an estimator of regularity in many scientific fields. It has proved to be a useful tool because of its ability to distinguish different system's dynamics when there is only available short-length noisy data. Incorrect parameter selection (embedding dimension $m$, threshold $r$ and data length $N$) and the presence of noise in the signal can undermine the ApEn discrimination capacity. In this work we show that $r_{max}$ ($ApEn(m,r_{max},N)=ApEn_{max}$) can also be used as a feature to discern between dynamics. Moreover, the combined use of $ApEn_{max}$ and $r_{max}$ allows a better discrimination capacity to be accomplished, even in the presence of noise. We conducted our studies using real physiological time series and simulated signals corresponding to both low- and high-dimensional systems. When $ApEn_{max}$ is incapable of discerning between different dynamics because of the noise presence, our results suggest that $r_{max}$ provides additional information that can be useful for classification purposes. Based on cross-validation tests, we conclude that, for short length noisy signals, the joint use of $ApEn_{max}$ and $r_{max}$ can significantly decrease the misclassification rate of a linear classifier in comparison with their isolated use.

  4. Energetics and structural properties of three-dimensional bosonic clusters near threshold

    SciTech Connect (OSTI)

    Hanna, G. J.; Blume, D. [Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)

    2006-12-15T23:59:59.000Z

    We treat three-dimensional bosonic clusters with up to N=40 atoms, interacting additively through two-body van der Waals potentials, in the near-threshold regime. Our study includes super-borromean systems with N atoms for which all subsystems are unbound. We determine the energetics and structural properties such as the expectation value of the interparticle distance as a function of the coupling strength. It has been shown that the coupling strength g{sub *}{sup (N)}, for which the N-body system becomes unbound, is bounded by the coupling constant g{sub *}{sup (N-1)}, for which the next smaller system with N-1 atoms becomes unbound, i.e., g{sub *}{sup (N)}{>=}(N-1)g{sub *}{sup (N-1)}/N. By fitting our numerically determined ground-state energies to a simple functional form with three fitting parameters, we determine the relationship between g{sub *}{sup (N)} and g{sub *}{sup (N-1)}. Our trimer and tetramer energies fall on the so-called Tjon line, which has been studied in nuclear physics. We confirm the existence of generalized Tjon lines for larger clusters. Signatures of the universal behavior of weakly bound three-dimensional clusters can possibly be observed in ultracold Bose gases.

  5. Method and system for controlling a synchronous machine over full operating range

    DOE Patents [OSTI]

    Walters, James E. (Carmel, IN); Gunawan, Fani S. (Westfield, IN); Xue, Yanhong (Westfield, IN)

    2002-01-01T23:59:59.000Z

    System and method for controlling a synchronous machine are provided. The method allows for calculating a stator voltage index. The method further allows for relating the magnitude of the stator voltage index against a threshold voltage value. An offset signal is generated based on the results of the relating step. A respective state of operation of the machine is determined. The offset signal is processed based on the respective state of the machine.

  6. A new cloud and aerosol layer detection method based on micropulse lidar measurements

    E-Print Network [OSTI]

    Li, Zhanqing

    A new cloud and aerosol layer detection method based on micropulse lidar measurements Chuanfeng algorithm to detect aerosols and clouds based on micropulse lidar measurements. A semidiscretization is then introduced. Combined with empirical threshold values, we determine if the signal waves indicate clouds

  7. e08-008: Exclusive study of deuteron electrodisintegration near threshold

    SciTech Connect (OSTI)

    Hanretty, Charles [JLAB, Newport News, VA (United States)

    2014-01-01T23:59:59.000Z

    The study of threshold electrodisintegration of and elastic scattering on the only stable two nucleon system, the deuteron, can reveal specific aspects of the N-N interaction. The simplicity of electrodisintegration along with the simplicity of the deuteron makes this study most appropriate for revealing these interactions. By using an incident beam of polarized electrons and by measuring the polarization of the recoiling proton, the ratio of the electric (G{sub E} ) and magnetic (G{sub M} ) form factors for d((vector e),e?(vector p)) (and p((vector e) ,e?(vector p))) reactions may be extracted. This experiment was conducted in Hall A at Jefferson Lab in Newport News, Virginia using a beam of polarized electrons provided by the CEBAF Accelerator incident on a liquid deuterium (and hydrogen) target. The scattered electron and the recoiling (polarized) proton were detected using the High Resolution Spectrometers of Hall A. To determine the polarization of the recoil proton, an analyzing material was placed perpendicular to the protons trajectory through the spectrometer, in front of a set of straw chambers. Due to the spin-orbit interactions involved in the scattering of the proton from the analyzer material, asymmetries seen in the distribution of events detected by these straw chambers reveal the polarization of the recoil proton. By tracking the spin procession of the polarized protons from the straw chambers back to the target, the transferred and induced polarization of the proton may be determined. The (double-spin) asymmetries observed in the straw chambers will first be studied for the well-known elastic p((vector e), e?(vector p)) process and compared to the asymmetries for d((vector e),e?(vector p))n(x{sub B}=1) . The analysis will then be repeated to determine how these asymmetries change with increasing x{sub B} (to the kinematic limit for deuteron electrodisintegration).

  8. Lead-chalcogenide mid-infrared vertical external cavity surface emitting lasers with improved threshold: Theory and experiment

    SciTech Connect (OSTI)

    Fill, Matthias [ETH Zurich, Laser Spectroscopy and Sensing Lab, 8093 Zurich (Switzerland) [ETH Zurich, Laser Spectroscopy and Sensing Lab, 8093 Zurich (Switzerland); Phocone AG, 8005 Zurich (Switzerland)] [Switzerland; Debernardi, Pierluigi [IEIIT-CNR, Torino 10129 (Italy)] [IEIIT-CNR, Torino 10129 (Italy); Felder, Ferdinand [Phocone AG, 8005 Zurich (Switzerland)] [Phocone AG, 8005 Zurich (Switzerland); Zogg, Hans [ETH Zurich (Switzerland)] [ETH Zurich (Switzerland)

    2013-11-11T23:59:59.000Z

    Mid-infrared Vertical External Cavity Surface Emitting Lasers (VECSEL) based on narrow gap lead-chalcogenide (IV-VI) semiconductors exhibit strongly reduced threshold powers if the active layers are structured laterally for improved optical confinement. This is predicted by 3-d optical calculations; they show that lateral optical confinement is needed to counteract the anti-guiding features of IV-VIs due to their negative temperature dependence of the refractive index. An experimental proof is performed with PbSe quantum well based VECSEL grown on a Si-substrate by molecular beam epitaxy and emitting around 3.3??m. With proper mesa-etching, the threshold intensity is about 8-times reduced.

  9. Estimating Methods

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1997-03-28T23:59:59.000Z

    Based on the project's scope, the purpose of the estimate, and the availability of estimating resources, the estimator can choose one or a combination of techniques when estimating an activity or project. Estimating methods, estimating indirect and direct costs, and other estimating considerations are discussed in this chapter.

  10. Characterization methods

    SciTech Connect (OSTI)

    Glass, J.T. [North Carolina State Univ., Raleigh (United States)

    1993-01-01T23:59:59.000Z

    Methods discussed in this compilation of notes and diagrams are Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and other surface analysis techniques (auger electron spectroscopy, x-ray photoelectron spectroscopy, electron energy loss spectroscopy, and scanning tunnelling microscopy). A comparative evaluation of different techniques is performed. In-vacuo and in-situ analyses are described.

  11. Method and system for managing an electrical output of a turbogenerator

    DOE Patents [OSTI]

    Stahlhut, Ronnie Dean (Bettendorf, IA); Vuk, Carl Thomas (Denver, IA)

    2009-06-02T23:59:59.000Z

    The system and method manages an electrical output of a turbogenerator in accordance with multiple modes. In a first mode, a direct current (DC) bus receives power from a turbogenerator output via a rectifier where turbogenerator revolutions per unit time (e.g., revolutions per minute (RPM)) or an electrical output level of a turbogenerator output meet or exceed a minimum threshold. In a second mode, if the turbogenerator revolutions per unit time or electrical output level of a turbogenerator output are less than the minimum threshold, the electric drive motor or a generator mechanically powered by the engine provides electrical energy to the direct current bus.

  12. Method and system for managing an electrical output of a turbogenerator

    DOE Patents [OSTI]

    Stahlhut, Ronnie Dean (Bettendorf, IA); Vuk, Carl Thomas (Denver, IA)

    2010-08-24T23:59:59.000Z

    The system and method manages an electrical output of a turbogenerator in accordance with multiple modes. In a first mode, a direct current (DC) bus receives power from a turbogenerator output via a rectifier where turbogenerator revolutions per unit time (e.g., revolutions per minute (RPM)) or an electrical output level of a turbogenerator output meet or exceed a minimum threshold. In a second mode, if the turbogenerator revolutions per unit time or electrical output level of a turbogenerator output are less than the minimum threshold, the electric drive motor or a generator mechanically powered by the engine provides electrical energy to the direct current bus.

  13. Infrared emitting device and method

    DOE Patents [OSTI]

    Kurtz, Steven R. (Albuquerque, NM); Biefeld, Robert M. (Albuquerque, NM); Dawson, L. Ralph (Albuquerque, NM); Howard, Arnold J. (Albuquerque, NM); Baucom, Kevin C. (Albuquerque, NM)

    1997-01-01T23:59:59.000Z

    An infrared emitting device and method. The infrared emitting device comprises a III-V compound semiconductor substrate upon which are grown a quantum-well active region having a plurality of quantum-well layers formed of a ternary alloy comprising InAsSb sandwiched between barrier layers formed of a ternary alloy having a smaller lattice constant and a larger energy bandgap than the quantum-well layers. The quantum-well layers are preferably compressively strained to increase the threshold energy for Auger recombination; and a method is provided for determining the preferred thickness for the quantum-well layers. Embodiments of the present invention are described having at least one cladding layer to increase the optical and carrier confinement in the active region, and to provide for waveguiding of the light generated within the active region. Examples have been set forth showing embodiments of the present invention as surface- and edge-emitting light emitting diodes (LEDs), an optically-pumped semiconductor laser, and an electrically-injected semiconductor diode laser. The light emission from each of the infrared emitting devices of the present invention is in the midwave infrared region of the spectrum from about 2 to 6 microns.

  14. Method of quantitating dsDNA

    DOE Patents [OSTI]

    Stark, Peter C. (Los Alamos, NM); Kuske, Cheryl R. (Los Alamos, NM); Mullen, Kenneth I. (Los Alamos, NM)

    2002-01-01T23:59:59.000Z

    A method for quantitating dsDNA in an aqueous sample solution containing an unknown amount of dsDNA. A first aqueous test solution containing a known amount of a fluorescent dye-dsDNA complex and at least one fluorescence-attenutating contaminant is prepared. The fluorescence intensity of the test solution is measured. The first test solution is diluted by a known amount to provide a second test solution having a known concentration of dsDNA. The fluorescence intensity of the second test solution is measured. Additional diluted test solutions are similarly prepared until a sufficiently dilute test solution having a known amount of dsDNA is prepared that has a fluorescence intensity that is not attenuated upon further dilution. The value of the maximum absorbance of this solution between 200-900 nanometers (nm), referred to herein as the threshold absorbance, is measured. A sample solution having an unknown amount of dsDNA and an absorbance identical to that of the sufficiently dilute test solution at the same chosen wavelength is prepared. Dye is then added to the sample solution to form the fluorescent dye-dsDNA-complex, after which the fluorescence intensity of the sample solution is measured and the quantity of dsDNA in the sample solution is determined. Once the threshold absorbance of a sample solution obtained from a particular environment has been determined, any similarly prepared sample solution taken from a similar environment and having the same value for the threshold absorbance can be quantified for dsDNA by adding a large excess of dye to the sample solution and measuring its fluorescence intensity.

  15. Method and apparatus for monitoring a hydrocarbon-selective catalytic reduction device

    DOE Patents [OSTI]

    Schmieg, Steven J; Viola, Michael B; Cheng, Shi-Wai S; Mulawa, Patricia A; Hilden, David L; Sloane, Thompson M; Lee, Jong H

    2014-05-06T23:59:59.000Z

    A method for monitoring a hydrocarbon-selective catalytic reactor device of an exhaust aftertreatment system of an internal combustion engine operating lean of stoichiometry includes injecting a reductant into an exhaust gas feedstream upstream of the hydrocarbon-selective catalytic reactor device at a predetermined mass flowrate of the reductant, and determining a space velocity associated with a predetermined forward portion of the hydrocarbon-selective catalytic reactor device. When the space velocity exceeds a predetermined threshold space velocity, a temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is determined, and a threshold temperature as a function of the space velocity and the mass flowrate of the reductant is determined. If the temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is below the threshold temperature, operation of the engine is controlled to regenerate the hydrocarbon-selective catalytic reactor device.

  16. $J/?$ production in Au+Au/Cu+Cu collisions at $\\sqrt{s}_{NN}$=200 GeV and the threshold model

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2006-10-09T23:59:59.000Z

    Using the QGP motivated threshold model, where all the $J/\\psi$'s are suppressed above a threshold density, we have analyzed the preliminary PHENIX data on the centrality dependence of nuclear modification factor for $J/\\psi$'s in Cu+Cu and in Au+Au collisions, at RHIC energy, $\\sqrt{s}_{NN}$=200 GeV. Centrality dependence of $J/\\psi$ suppression in Au+Au collisions are well explained in the model for threshold densities in ranges of 3.6-3.7 $fm^{-2}$. $J/\\psi$ suppression in Cu+Cu collisions on the other hand are not explained in the model.

  17. Method to reduce damage to backing plate

    DOE Patents [OSTI]

    Perry, Michael D. (Livermore, CA); Banks, Paul S. (Livermore, CA); Stuart, Brent C. (Fremont, CA)

    2001-01-01T23:59:59.000Z

    The present invention is a method for penetrating a workpiece using an ultra-short pulse laser beam without causing damage to subsequent surfaces facing the laser. Several embodiments are shown which place holes in fuel injectors without damaging the back surface of the sack in which the fuel is ejected. In one embodiment, pulses from an ultra short pulse laser remove about 10 nm to 1000 nm of material per pulse. In one embodiment, a plasma source is attached to the fuel injector and initiated by common methods such as microwave energy. In another embodiment of the invention, the sack void is filled with a solid. In one other embodiment, a high viscosity liquid is placed within the sack. In general, high-viscosity liquids preferably used in this invention should have a high damage threshold and have a diffusing property.

  18. Gelcasting methods

    DOE Patents [OSTI]

    Walls, Claudia A. (Oak Ridge, TN); Kirby, Glen H. (Knoxville, TN); Janney, Mark A. (Knoxville, TN); Omatete, Ogbemi O. (Knoxville, TN); Nunn, Stephen D. (Knoxville, TN); McMillan, April D. (Knoxville, TN)

    2000-01-01T23:59:59.000Z

    A method of gelcasting includes the steps of providing a solution of at least hydroxymethylacrylamide (HMAM) and water. At least one inorganic powder is added to the mixture. At least one initiator system is provided to polymerize the HMAM. The initiator polymerizes the HMAM and water, to form a firm hydrogel that contains the inorganic powder. One or more comonomers can be polymerized with the HMAM monomer, to alter the final properties of the gelcast material. Additionally, one or more additives can be included in the polymerization mixture, to alter the properties of the gelcast material.

  19. Evaluation of Shear Strength Threshold of Concern for Retrieval of Interim-Stored K-Basin Sludge in the Hanford Site

    SciTech Connect (OSTI)

    Onishi, Yasuo; Yokuda, Satoru T.; Schmidt, Andrew J.

    2010-11-01T23:59:59.000Z

    K-Basin sludge will be recovered into the Sludge Transport and Storage Containers (STSCs) and will be stored in the T Plant for interim storage (at least 10 years). Long-term sludge storage tests conducted by Pacific Northwest National Laboratory show that high uranium content K Basin sludge can self-cement and form a strong sludge with a bulk shear strength of up to 65 kPa. Some of this sludge has "paste" and "chunks" with shear strengths of approximately 3~5 kPa and 380 ~ 770 kPa, respectively. High uranium content sludge samples subjected to hydrothermal testing (e.g., 185°C, 10 h) have been observed to form agglomerates with a shear strength up to 170 kPa. After interim storage at T Plant, the sludge in the STSCs will be mobilized by water jets impinging the sludge. The objective of the evaluation was to determine the range of sludge shear strength for which there is high confidence that a water-jet retrieval system can mobilize stored K-Basin sludge from STSCs. The shear strength at which the sludge can be retrieved is defined as the "shear strength threshold of concern." If the sludge shear strength is greater than the value of the shear strength threshold of concern, a water-jet retrieval system will be unlikely to mobilize the sludge up to the container’s walls. The shear strength threshold of concern can be compared with the range of possible shear strengths of K-Basin stored sludge to determine if the current post interim-storage, water-jet retrieval method is adequate. Fourteen effective cleaning radius (ECR) models were reviewed, and their validity was examined by applying them to Hanford 241-SY-101 and 241-AZ-101 Tanks to reproduce the measured ECR produced by the mixer pumps. The validation test identified that the Powell-3 and Crowe-2 ECR models are more accurate than other ECR models reviewed. These ECR models were used to address a question as to whether the effective cleaning radius of a water jet is sufficient or if it can be readily expanded to cover the range of possible shear strengths. These results will assist CH2M HILL Plateau Remediation Company (CHPRC) to establish the technical basis of the feasibility of the sludge retrieval and storage plan and to develop an adequate water jet system to retrieve the stored K-Basin sludge in the STSCs. The STSCs are 2:1 elliptical-head vessels, 58 inches in diameter and 105 inches tall. Each STSC will contain 0.5 to 2.1 m3 of settled sludge with the specific loading dependent upon sludge type.

  20. Submilliampere threshold current pseudomorphic InGaAs/AlGaAs buried-heterostructure quantum well lasers grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Eng, L.E.; Chen, T.R.; Sanders, S.; Zhuang, Y.H.; Zhao, B.; Yariv, A. (Department of Applied Physics, California Institute of Technology, Pasadena, California 91125 (US)); Morkoc, H. (The Coordinated Science Laboratory, University of Illinois, Urbana, Illinois 61801)

    1989-10-02T23:59:59.000Z

    We report on low threshold current strained InGaAs/AlGaAs single quantum well lasers grown by molecular beam epitaxy. Broad-area threshold current densities of 114 A/cm{sup 2} at 990 nm were measured for 1540-{mu}m-long lasers. Threshold currents of 2.4 mA at 950 nm were obtained for an uncoated buried-heterostructure device with a 2-{mu}m-wide stripe and 425-{mu}m-long cavity. With reflective coatings the best device showed 0.9 mA threshold current ({ital L}=225 {mu}m). Preliminary modulation measurements show bandwidths up to 5.5 GHz limited by the detector response.

  1. 216 J. Opt. Soc. Am. B/Vol. 13, No. 1/January 1996 D. von der Linde and H. Schuler Breakdown threshold and plasma formation

    E-Print Network [OSTI]

    von der Linde, D.

    216 J. Opt. Soc. Am. B/Vol. 13, No. 1/January 1996 D. von der Linde and H. Sch¨uler Breakdown threshold and plasma formation in femtosecond laser­solid interaction D. von der Linde and H. Sch

  2. SupplementalFigures1 Supplementary Figure S1: Sample Mean Excess (SME) for a range of thresholds at the grid point closest to 3

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    SupplementalFigures1 2 Supplementary Figure S1: Sample Mean Excess (SME) for a range of thresholds at the grid point closest to 3 Bergen, Norway in the BCMHIRHAM5 downscaling. The SME

  3. Method and apparatus for biological sequence comparison

    DOE Patents [OSTI]

    Marr, T.G.; Chang, W.I.

    1997-12-23T23:59:59.000Z

    A method and apparatus are disclosed for comparing biological sequences from a known source of sequences, with a subject (query) sequence. The apparatus takes as input a set of target similarity levels (such as evolutionary distances in units of PAM), and finds all fragments of known sequences that are similar to the subject sequence at each target similarity level, and are long enough to be statistically significant. The invention device filters out fragments from the known sequences that are too short, or have a lower average similarity to the subject sequence than is required by each target similarity level. The subject sequence is then compared only to the remaining known sequences to find the best matches. The filtering member divides the subject sequence into overlapping blocks, each block being sufficiently large to contain a minimum-length alignment from a known sequence. For each block, the filter member compares the block with every possible short fragment in the known sequences and determines a best match for each comparison. The determined set of short fragment best matches for the block provide an upper threshold on alignment values. Regions of a certain length from the known sequences that have a mean alignment value upper threshold greater than a target unit score are concatenated to form a union. The current block is compared to the union and provides an indication of best local alignment with the subject sequence. 5 figs.

  4. Method and apparatus for biological sequence comparison

    DOE Patents [OSTI]

    Marr, Thomas G. (Huntington, NY); Chang, William I-Wei (Huntington, NY)

    1997-01-01T23:59:59.000Z

    A method and apparatus for comparing biological sequences from a known source of sequences, with a subject (query) sequence. The apparatus takes as input a set of target similarity levels (such as evolutionary distances in units of PAM), and finds all fragments of known sequences that are similar to the subject sequence at each target similarity level, and are long enough to be statistically significant. The invention device filters out fragments from the known sequences that are too short, or have a lower average similarity to the subject sequence than is required by each target similarity level. The subject sequence is then compared only to the remaining known sequences to find the best matches. The filtering member divides the subject sequence into overlapping blocks, each block being sufficiently large to contain a minimum-length alignment from a known sequence. For each block, the filter member compares the block with every possible short fragment in the known sequences and determines a best match for each comparison. The determined set of short fragment best matches for the block provide an upper threshold on alignment values. Regions of a certain length from the known sequences that have a mean alignment value upper threshold greater than a target unit score are concatenated to form a union. The current block is compared to the union and provides an indication of best local alignment with the subject sequence.

  5. Ultralow-threshold graded-index separate-confinement single quantum well buried heterostructure (Al,Ga)As lasers with high reflectivity coatings

    SciTech Connect (OSTI)

    Derry, P.L.; Yariv, A.; Lau, K.Y.; Bar-Chaim, N.; Lee, K.; Rosenberg, J.

    1987-06-22T23:59:59.000Z

    Unlike conventional semiconductor lasers, single quantum well lasers with high reflectively coatings have dramatically reduced threshold currents as a result of the smaller volume of the (active) quantum well region. A cw threshold current of 0.95 mA was obtained for a buried graded-index separate-confinement heterostructure single quantum well laser with facet reflectivities of --70%, a cavity length of 250 ..mu..m, and an active region stripe width of 1 ..mu..m.

  6. Complete direct method for electron-hydrogen scattering: Application to the collinear and Temkin-Poet models

    SciTech Connect (OSTI)

    Bartlett, Philip L.; Stelbovics, Andris T. [Centre for Atomic, Molecular and Surface Physics, Murdoch University, Perth 6150 (Australia)

    2004-02-01T23:59:59.000Z

    We present an efficient generalization of the exterior complex scaling (ECS) method to extract discrete inelastic and ionization amplitudes for electron-impact scattering of atomic hydrogen. This fully quantal method is demonstrated over a range of energies for the collinear and Temkin-Poet models and near-threshold ionization is examined in detail for singlet and triplet scattering. Our numerical calculations for total ionization cross sections near threshold strongly support the classical threshold law of Wannier [Phys. Rev. 90, 817 (1953)] ({sigma}{proportional_to}E{sup 1.128{+-}}{sup 0.004}) for the L=0 singlet collinear model and the semiclassical threshold law of Peterkop [J. Phys. B 16, L587 (1983)] ({sigma}{proportional_to}E{sup 3.37{+-}}{sup 0.02}) for the L=0 triplet collinear model, and are consistent with the semiclassical threshold law of Macek and Ihra [Phys. Rev. A 55, 2024 (1997)] ({sigma}{proportional_to}exp[(-6.87{+-}0.01)E{sup -1/6}]) for the singlet Temkin-Poet model.

  7. Casting methods

    DOE Patents [OSTI]

    Marsden, Kenneth C.; Meyer, Mitchell K.; Grover, Blair K.; Fielding, Randall S.; Wolfensberger, Billy W.

    2012-12-18T23:59:59.000Z

    A casting device includes a covered crucible having a top opening and a bottom orifice, a lid covering the top opening, a stopper rod sealing the bottom orifice, and a reusable mold having at least one chamber, a top end of the chamber being open to and positioned below the bottom orifice and a vacuum tap into the chamber being below the top end of the chamber. A casting method includes charging a crucible with a solid material and covering the crucible, heating the crucible, melting the material, evacuating a chamber of a mold to less than 1 atm absolute through a vacuum tap into the chamber, draining the melted material into the evacuated chamber, solidifying the material in the chamber, and removing the solidified material from the chamber without damaging the chamber.

  8. Tensiometer methods

    DOE Patents [OSTI]

    Grover, Blair K.; Hubbell, Joel M.; Sisson, James B.; Casper, William L.

    2005-12-20T23:59:59.000Z

    A method for collecting data regarding a matric potential of a media includes providing a tensiometer having a stainless steel tensiometer casing, the stainless steel tensiometer casing comprising a tip portion which includes a wetted porous stainless steel membrane through which a matric potential of a media is sensed; driving the tensiometer into the media using an insertion tube comprising a plurality of probe casing which are selectively coupled to form the insertion tube as the tensiometer is progressively driven deeper into the media, wherein the wetted porous stainless steel membrane is in contact with the media; and sensing the matric potential the media exerts on the wetted porous stainless steel membrane by a pressure sensor in fluid hydraulic connection with the porous stainless steel membrane. A tensiometer includes a stainless steel casing.

  9. A continuum model with a percolation threshold and tunneling-assisted interfacial conductivity for carbon nanotube-based nanocomposites

    SciTech Connect (OSTI)

    Wang, Yang; Weng, George J., E-mail: weng@jove.rutgers.edu [Department of Mechanical and Aerospace Engineering, Rutgers University, New Brunswick, New Jersey 08903 (United States); Meguid, Shaker A. [Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8 (Canada); Hamouda, Abdel Magid [Department of Mechanical and Industrial Engineering, Qatar University, Doha (Qatar)

    2014-05-21T23:59:59.000Z

    A continuum model that possesses several desirable features of the electrical conduction process in carbon-nanotube (CNT) based nanocomposites is developed. Three basic elements are included: (i) percolation threshold, (ii) interface effects, and (iii) tunneling-assisted interfacial conductivity. We approach the first one through the selection of an effective medium theory. We approach the second one by the introduction of a diminishing layer of interface with an interfacial conductivity to build a 'thinly coated' CNT. The third one is introduced through the observation that interface conductivity can be enhanced by electron tunneling which in turn can be facilitated with the formation of CNT networks. We treat this last issue in a continuum fashion by taking the network formation as a statistical process that can be represented by Cauchy's probability density function. The outcome is a simple and yet widely useful model that can simultaneously capture all these fundamental characteristics. It is demonstrated that, without considering the interface effect, the predicted conductivity would be too high, and that, without accounting for the additional contribution from the tunneling-assisted interfacial conductivity, the predicted conductivity beyond the percolation threshold would be too low. It is with the consideration of all three elements that the theory can fully account for the experimentally measured data. We further use the developed model to demonstrate that, despite the anisotropy of the intrinsic CNT conductivity, it is its axial component along the CNT direction that dominates the overall conductivity. This theory is also proved that, even with a totally insulating matrix, it is still capable of delivering non-zero conductivity beyond the percolation threshold.

  10. Dependence of the L- to H-mode Power Threshold on Toroidal Rotation and the Link to Edge Turbulence Dynamics

    SciTech Connect (OSTI)

    McKee, G; Gohil, P; Schlossberg, D; Boedo, J; Burrell, K; deGrassie, J; Groebner, R; Makowski, M; Moyer, R; Petty, C; Rhodes, T; Schmitz, L; Shafer, M; Solomon, W; Umansky, M; Wang, G; White, A; Xu, X

    2008-10-13T23:59:59.000Z

    The injected power required to induce a transition from L-mode to H-mode plasmas is found to depend strongly on the injected neutral beam torque and consequent plasma toroidal rotation. Edge turbulence and flows, measured near the outboard midplane of the plasma (0.85 < r/a < 1.0) on DIII-D with the high-sensitivity 2D beam emission spectroscopy (BES) system, likewise vary with rotation and suggest a causative connection. The L-H power threshold in plasmas with the ion {del}B drift away from the X-point decreases from 4-6 MW with co-current beam injection, to 2-3 MW with near zero net injected torque, and to <2 MW with counter injection. Plasmas with the ion {del}B drift towards the X-point exhibit a qualitatively similar though less pronounced power threshold dependence on rotation. 2D edge turbulence measurements with BES show an increasing poloidal flow shear as the L-H transition is approached in all conditions. At low rotation, the poloidal flow of turbulent eddies near the edge reverses prior to the L-H transition, generating a significant poloidal flow shear that exceeds the measured turbulence decorrelation rate. This increased poloidal turbulence velocity shear may facilitate the L-H transition. No such reversal is observed in high rotation plasmas. The poloidal turbulence velocity spectrum exhibits a transition from a Geodesic Acoustic Mode zonal flow to a higher-power, lower frequency, zero-mean-frequency zonal flow as rotation varies from co-current to balanced during a torque scan at constant injected neutral beam power, perhaps also facilitating the L-H transition. This reduced power threshold at lower toroidal rotation may benefit inherently low-rotation plasmas such as ITER.

  11. Infrared emitting device and method

    DOE Patents [OSTI]

    Kurtz, S.R.; Biefeld, R.M.; Dawson, L.R.; Howard, A.J.; Baucom, K.C.

    1997-04-29T23:59:59.000Z

    The infrared emitting device comprises a III-V compound semiconductor substrate upon which are grown a quantum-well active region having a plurality of quantum-well layers formed of a ternary alloy comprising InAsSb sandwiched between barrier layers formed of a ternary alloy having a smaller lattice constant and a larger energy bandgap than the quantum-well layers. The quantum-well layers are preferably compressively strained to increase the threshold energy for Auger recombination; and a method is provided for determining the preferred thickness for the quantum-well layers. Embodiments of the present invention are described having at least one cladding layer to increase the optical and carrier confinement in the active region, and to provide for waveguiding of the light generated within the active region. Examples have been set forth showing embodiments of the present invention as surface- and edge-emitting light emitting diodes (LEDs), an optically-pumped semiconductor laser, and an electrically-injected semiconductor diode laser. The light emission from each of the infrared emitting devices of the present invention is in the midwave infrared region of the spectrum from about 2 to 6 microns. 8 figs.

  12. Reconstructing the WIMP Velocity Distribution from Direct Dark Matter Detection Data with a Non-negligible Threshold Energy

    E-Print Network [OSTI]

    Shan, Chung-Lin

    2015-01-01T23:59:59.000Z

    In this paper, we investigate the modification of our expressions developed for the model-independent data analysis procedure of the reconstruction of the (time-averaged) one-dimensional velocity distribution of Galactic Weakly Interacting Massive Particles (WIMPs) with a non-negligible experimental threshold energy. Our numerical simulations show that, for a minimal reconstructable velocity of as high as O(200) km/s, our model-independent modification of the estimator for the normalization constant could provide precise reconstructed velocity distribution points to match the true WIMP velocity distribution with a <~ 10% bias.

  13. Direct Production of Tripartite Pump-Signal-Idler Entanglement in the Above-Threshold Optical Parametric Oscillator

    E-Print Network [OSTI]

    A. S. Villar; M. Martinelli; C. Fabre; P. Nussenzveig

    2006-10-09T23:59:59.000Z

    We calculate the quantum correlations existing among the three output fields (pump, signal, and idler) of a triply resonant non-degenerate Optical Parametric Oscillator operating above threshold. By applying the standard criteria [P. van Loock and A. Furusawa, Phys. Rev. A 67, 052315 (2003)], we show that strong tripartite continuous-variable entanglement is present in this well-known and simple system. Furthermore, since the entanglement is generated directly from a nonlinear process, the three entangled fields can have very different frequencies, opening the way for multicolored quantum information networks.

  14. Hadron Physics at the Charm and Bottom Thresholds and Other Novel QCD Physics Topics at the NICA Accelerator Facility

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; /SLAC

    2012-06-20T23:59:59.000Z

    The NICA collider project at the Joint Institute for Nuclear Research in Dubna will have the capability of colliding protons, polarized deuterons, and nuclei at an effective nucleon-nucleon center-of mass energy in the range {radical}s{sub NN} = 4 to 11 GeV. I briefly survey a number of novel hadron physics processes which can be investigated at the NICA collider. The topics include the formation of exotic heavy quark resonances near the charm and bottom thresholds, intrinsic strangeness, charm, and bottom phenomena, hidden-color degrees of freedom in nuclei, color transparency, single-spin asymmetries, the RHIC baryon anomaly, and non-universal antishadowing.

  15. Deep sub-threshold $?^-$ production in Ar+KCl reactions at 1.76A GeV

    E-Print Network [OSTI]

    G. Agakishiev; A. Balanda; R. Bassini; D. Belver; A. V. Belyaev; A. Blanco; M. Böhmer; J. L. Boyard; P. Braun-Munzinger; P. Cabanelas; E. Castro; S. Chernenko; T. Christ; M. Destefanis; J. Díaz; F. Dohrmann; A. Dybczak; T. Eberl; L. Fabbietti; O. V. Fateev; P. Finocchiaro; P. Fonte; J. Friese; I. Fröhlich; T. Galatyuk; J. A. Garzón; R. Gernhäuser; A. Gil; C. Gilardi; M. Golubeva; D. González-Díaz; F. Guber; T. Hennino; R. Holzmann; I. Iori; A. Ivashkin; M. Jurkovic; B. Kämpfer; K. Kanaki; T. Karavicheva; D. Kirschner; I. Koenig; W. Koenig; B. W. Kolb; R. Kotte; F. Krizek; R. Krücken; W. Kühn; A. Kugler; A. Kurepin; S. Lang; J. S. Lange; K. Lapidus; T. Liu; L. Lopes; M. Lorenz; L. Maier; A. Mangiarotti; J. Markert; V. Metag; B. Michalska; J. Michel; D. Mishra; E. Morinière; J. Mousa; C. Müntz; L. Naumann; J. Otwinowski; Y. C. Pachmayer; M. Palka; Y. Parpottas; V. Pechenov; O. Pechenova; J. Pietraszko; W. Przygoda; B. Ramstein; A. Reshetin; M. Roy-Stephan; A. Rustamov; A. Sadovsky; B. Sailer; P. Salabura; A. Schmah; Yu. G. Sobolev; S. Spataro; B. Spruck; H. Ströbele; J. Stroth; C. Sturm; M. Sudol; A. Tarantola; K. Teilab; P. Tlusty; M. Traxler; R. Trebacz; H. Tsertos; V. Wagner; M. Weber; M. Wisniowski; T. Wojcik; J. Wüstenfeld; S. Yurevich; Y. V. Zanevsky; P. Zhou

    2009-07-21T23:59:59.000Z

    We report first results on a deep sub-threshold production of the doubly strange hyperon $\\Xi^-$ in a heavy-ion reaction. At a beam energy of 1.76A GeV the reaction Ar+KCl was studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18/GSI. A high-statistics and high-purity $\\Lambda$ sample was collected, allowing for the investigation of the decay channel $\\Xi^- \\to \\Lambda \\pi^-$. The deduced $\\Xi^-/(\\Lambda+\\Sigma^0)$ production ratio of $(5.6 \\pm 1.2 ^{+1.8}_{-1.7})\\cdot 10^{-3}$ is significantly larger than available model predictions.

  16. Fluid models for evaluating threshold-based control policies for survivability of a distributed network

    E-Print Network [OSTI]

    Gautam, Natarajan

    in change of work load characteristics. Therefore, the resource sharing mechanism must be robust to work Abstract The objective of this paper is to develop methods to improve the survivability of a distributed by the agent on the machine but also by other applications running on the machine. Based on the load

  17. Transition threshold in Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses

    SciTech Connect (OSTI)

    Wei, Wen-Hou [Department of Applied Physics, Chongqing University, Chongqing 401331 (China); Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Fang, Liang, E-mail: lfang@cqu.edu.cn [Department of Applied Physics, Chongqing University, Chongqing 401331 (China); Shen, Xiang [Laboratory of Infrared Material and Devices, Advanced Technology Research Institute, Ningbo University, Ningbo 315211 (China); Wang, Rong-Ping [Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2014-03-21T23:59:59.000Z

    Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses with Ge content from 7.5 to 32.5?at.?% have been prepared by melt-quench technique, and the physical parameters including glass transition temperature (T{sub g}), density (?), compactness (C), shear elastic moduli (C{sub s}), compression elastic moduli (C{sub c}), refractive index (n), and optical bandgap (E{sub g}) have been investigated. While all these physical parameters show threshold behavior in the glass with a chemically stoichiometric composition. Raman spectra analysis also indicates that, with increasing Ge content, Se-chains or rings gradually disappear until all Se-atoms are consumed in the glass with a chemically stoichiometric composition. With further increasing Ge content, homopolar Ge-Ge and Sb-Sb bonds are formed and the chemical order in the glasses is violated. The threshold behavior of the physical properties in the Ge{sub x}Sb{sub 10}Se{sub 90?x} glasses can be traced to demixing of networks above the chemically stoichiometric composition.

  18. Dressed-bound-state molecular strong-field approximation: Application to above-threshold ionization of heteronuclear diatomic molecules

    SciTech Connect (OSTI)

    Hasovic, E. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, BA-71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Strasse 2a, DE-12489 Berlin (Germany); Busuladzic, M. [Medical Faculty, University of Sarajevo, Cekalusa 90, BA-71000 Sarajevo (Bosnia and Herzegowina); Becker, W. [Max-Born-Institut, Max-Born-Strasse 2a, DE-12489 Berlin (Germany); Milosevic, D. B. [Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, BA-71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Strasse 2a, DE-12489 Berlin (Germany); Academy of Sciences and Arts of Bosnia and Herzegovina, Bistrik 7, BA-71000 Sarajevo (Bosnia and Herzegowina)

    2011-12-15T23:59:59.000Z

    The molecular strong-field approximation (MSFA), which includes dressing of the molecular bound state, is introduced and applied to above-threshold ionization of heteronuclear diatomic molecules. Expressions for the laser-induced molecular dipole and polarizability as functions of the laser parameters (intensity and frequency) and molecular parameters [molecular orientation, dipole, and parallel and perpendicular polarizabilities of the highest occupied molecular orbital (HOMO)] are presented. Our previous MSFA theory, which incorporates the rescattering effects, is generalized from homonuclear to heteronuclear diatomic molecules. Angle- and energy-resolved high-order above-threshold ionization spectra of oriented heteronuclear diatomic molecules, exemplified by the carbon monoxide (CO) molecule, exhibit pronounced minima, which can be related to the shape of their HOMO-electron-density distribution. For the CO molecule we have found an analytical condition for the positions of these minima. We have also shown that the effect of the dressing of the HOMO is twofold: (i) the laser-induced Stark shift decreases the ionization yield and (ii) the laser-induced time-dependent dipole and polarizability change the oscillatory structure of the spectra.

  19. Ultralow-threshold laser and blue shift cooperative luminescence in a Yb{sup 3+} doped silica microsphere

    SciTech Connect (OSTI)

    Huang, Yantang, E-mail: g@fzu.edu.cn; Huang, Yu; Zhang, Peijin [College of Physics and Information Engineering, Fuzhou University, Fu Zhou, 350108 (China)] [College of Physics and Information Engineering, Fuzhou University, Fu Zhou, 350108 (China); Guo, Changlei [College of Physics and Information Engineering, Fuzhou University, Fu Zhou, 350108 (China) [College of Physics and Information Engineering, Fuzhou University, Fu Zhou, 350108 (China); Department of Electronic Engineering, Institute of Optoelectronic Technology, Xiamen University, Xiamen, 361005 (China)

    2014-02-15T23:59:59.000Z

    An experimental investigation on ultralow threshold laser and blue shift cooperative luminescence (CL) in a Yb{sup 3+} doped silica microsphere (YDSM) with continuous-wave 976 nm laser diode pumping is reported. The experimental results show that the YDSM emits laser oscillation with ultralow threshold of 2.62 ?W, and the laser spectrum is modulated by the microsphere morphology characteristics. In addition, blue emission of YDSM is also observed with the increase of pump power, which is supposed to be generated by CL of excited Yb ion-pairs with the absorption of 976 nm photons and Si-O vibration phonons, and the process is explained with an energy level diagram. This property of the blue shift CL with phonons absorption in the Yb{sup 3+}doped microcavity makes it attractive for the application of laser cooling based on anti-Stokes fluorescence emission, if the Yb{sup 3+}doped microcavity made from with low phonon energy host materials.

  20. Lowering the background level and the energy threshold of Micromegas x-ray detectors for axion searches

    E-Print Network [OSTI]

    F. J. Iguaz; S. Aune; F. Aznar; J. F. Castel; T. Dafni; M. Davenport; E. Ferrer-Ribas; J. Galan; J. A. Garcia; J. G. Garza; I. Giomataris; I. G. Irastorza; T. Papaevangelou; A. Rodriguez; A. Tomas; T. Vafeiadis; S. C. Yildiz

    2015-01-07T23:59:59.000Z

    Axion helioscopes search for solar axions by their conversion in x-rays in the presence of high magnetic fields. The use of low background x-ray detectors is an essential component contributing to the sensitivity of these searches. In this work, we review the recent advances on Micromegas detectors used in the CERN Axion Solar Telescope (CAST) and proposed for the future International Axion Observatory (IAXO). The actual setup in CAST has achieved background levels below 10$^{-6}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$, a factor 100 lower than the first generation of Micromegas detectors. This reduction is based on active and passive shielding techniques, the selection of radiopure materials, offline discrimination techniques and the high granularity of the readout. We describe in detail the background model of the detector, based on its operation at CAST site and at the Canfranc Underground Laboratory (LSC), as well as on Geant4 simulations. The best levels currently achieved at LSC are low than 10$^{-7}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$ and show good prospects for the application of this technology in IAXO. Finally, we present some ideas and results for reducing the energy threshold of these detectors below 1 keV, using high-transparent windows, autotrigger electronics and studying the cluster shape at different energies. As a high flux of axion-like-particles is expected in this energy range, a sub-keV threshold detector could enlarge the physics case of axion helioscopes.

  1. Damage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength

    SciTech Connect (OSTI)

    Hau-Riege, S; London, R A; Bionta, R M; McKernan, M A; Baker, S L; Krzywinski, J; Sobierajski, R; Nietubyc, R; Pelka, J B; Jurek, M; Klinger, D; Juha, L; Chalupsky, J; Cihelka, J; Hajkova, V; Koptyaev, S; Velyhan, A; Krasa, J; Kuba, J; Tiedtke, K; Toleikis, S; Tschentscher, T; Wabnitz, H; Bergh, M; Caleman, C; Sokolowski-Tinten, K; Stojanovic, N; Zastrau, U; Tronnier, A; Meyer-ter-Vehn, J

    2007-12-03T23:59:59.000Z

    We exposed samples of B4C, amorphous C, chemical-vapor-deposition (CVD)-diamond C, Si, and SiC to single 25 fs-long pulses of 32.5 nm free-electron-laser radiation at fluences of up to 2.2 J/cm{sup 2}. The samples were chosen as candidate materials for x-ray free electron laser (XFEL) optics. We found that the threshold for surface-damage is on the order of the fluence required for thermal melting. For larger fluences, the crater depths correspond to temperatures on the order of the critical temperature, suggesting that the craters are formed by two-phase vaporization [1]. XFELs have the promise of producing extremely high-intensity ultrashort pulses of coherent, monochromatic radiation in the 1 to 10 keV regime. The expected high output fluence and short pulse duration pose significant challenges to the optical components, including radiation damage. It has not been possible to obtain direct experimental verification of the expected damage thresholds since appropriate x-ray sources are not yet available. FLASH has allowed us to study the interaction of high-fluence short-duration photon pulses with materials at the shortest wavelength possible to date. With these experiments, we have come closer to the extreme conditions expected in XFEL-matter interaction scenarios than previously possible.

  2. Precision calculation of above-threshold multiphoton ionization in intense short-wavelength laser fields: The momentum-space approach and time-dependent generalized pseudospectral method

    E-Print Network [OSTI]

    Chu, Shih-I; Zhou, Zhongyuan

    2011-01-19T23:59:59.000Z

    . Villoresi, M. Nisoli, S. Stagira, E. Priori, and S. De Silvestri, Nature (London) 414, 182 (2001). [26] G. G. Paulus, F. Lindner, H. Walther, A. Baltuska, E. Goulielmakis, M. Lezius, and F. Krausz, Phys. Rev. Lett. 91, 253004 (2003). [27] A. Rudenko, K.... Zrost, C. D. Schro¨ter, V. L. B. de Jesus, B. Feuerstein, R. Moshammer, and J. Ullrich, J. Phys. B 37, L407 (2004). [28] A. Rudenko, K. Zrost, T. Ergler, A. B. Voitkiv, B. Najjari, V. L. B. de Jesus, B. Feuerstein, C. D. Schro¨ter, R. Moshammer, and J...

  3. Systems and methods for deactivating a matrix converter

    DOE Patents [OSTI]

    Ransom, Ray M.

    2013-04-02T23:59:59.000Z

    Systems and methods are provided for deactivating a matrix conversion module. An electrical system comprises an alternating current (AC) interface, a matrix conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the matrix conversion module, and a control module. The control module is coupled to the matrix conversion module, and in response to a shutdown condition, the control module is configured to operate the matrix conversion module to deactivate the first conversion module when a magnitude of a current through the inductive element is less than a threshold value.

  4. Method and apparatus for welding precipitation hardenable materials

    DOE Patents [OSTI]

    Murray, Jr., Holt (Hopewell, NJ); Harris, Ian D. (Dublin, OH); Ratka, John O. (Cleveland Heights, OH); Spiegelberg, William D. (Parma, OH)

    1994-01-01T23:59:59.000Z

    A method for welding together members consisting of precipitation age hardened materials includes the steps of selecting a weld filler material that has substantially the same composition as the materials being joined, and an age hardening characteristic temperature age threshold below that of the aging kinetic temperature range of the materials being joined, whereby after welding the members together, the resulting weld and heat affected zone (HAZ) are heat treated at a temperature below that of the kinetic temperature range of the materials joined, for obtaining substantially the same mechanical characteristics for the weld and HAZ, as for the parent material of the members joined.

  5. Method and apparatus for welding precipitation hardenable materials

    DOE Patents [OSTI]

    Murray, H. Jr.; Harris, I.D.; Ratka, J.O.; Spiegelberg, W.D.

    1994-06-28T23:59:59.000Z

    A method for welding together members consisting of precipitation age hardened materials includes the steps of selecting a weld filler material that has substantially the same composition as the materials being joined, and an age hardening characteristic temperature age threshold below that of the aging kinetic temperature range of the materials being joined, whereby after welding the members together, the resulting weld and heat affected zone (HAZ) are heat treated at a temperature below that of the kinetic temperature range of the materials joined, for obtaining substantially the same mechanical characteristics for the weld and HAZ, as for the parent material of the members joined. 5 figures.

  6. Methods and systems for detecting abnormal digital traffic

    DOE Patents [OSTI]

    Goranson, Craig A [Kennewick, WA; Burnette, John R [Kennewick, WA

    2011-03-22T23:59:59.000Z

    Aspects of the present invention encompass methods and systems for detecting abnormal digital traffic by assigning characterizations of network behaviors according to knowledge nodes and calculating a confidence value based on the characterizations from at least one knowledge node and on weighting factors associated with the knowledge nodes. The knowledge nodes include a characterization model based on prior network information. At least one of the knowledge nodes should not be based on fixed thresholds or signatures. The confidence value includes a quantification of the degree of confidence that the network behaviors constitute abnormal network traffic.

  7. Low-threshold (--600 A/cm/sup 2/ at room temperature) GaAs/AlGaAs lasers on Si (100)

    SciTech Connect (OSTI)

    Chen, H.Z.; Ghaffari, A.; Wang, H.; Morkoc, H.; Yariv, A.

    1987-10-26T23:59:59.000Z

    Low-threshold graded-refractive-index GaAs/AlGaAs laser structures were grown on Si (100) by molecular beam epitaxy and tested at room temperature under a probe station. Broad area devices having widths of 110--120 ..mu..m and cavity lengths of --500--1210 ..mu..m exhibited threshold current densities as low as 600 A/cm/sup 2/ and total slope efficiencies of as high as 0.75 W/A. The thresholds fell in the range of 600--1000 A/cm/sup 2/ in three different wafers, and it is assumed that the quality of the facets accounts for most of the spread in results.

  8. Determination of the melting threshold of TiO{sub 2} thin films processed by excimer laser irradiation

    SciTech Connect (OSTI)

    Van Overschelde, O. [Chimie des Interactions Plasma-Surface, Universite de Mons, 23, Place du Parc, 7000 Mons (Belgium); Delsate, T. [Service de Physique Theorique et Mathematique, Universite de Mons, 6 Avenue du champ de Mars, 7000 Mons (Belgium); Snyders, R. [Chimie des Interactions Plasma-Surface, Universite de Mons, 23, Place du Parc, 7000 Mons (Belgium); Materia Nova Research Center, 1 Avenue Copernic, 7000 Mons (Belgium)

    2012-06-15T23:59:59.000Z

    Processing surfaces by laser needs an understanding of the mechanisms generated by irradiation. In this work, to gain understanding of the mechanisms occurring during irradiation of TiO{sub 2} thin films by means of KrF excimer laser, we have performed infrared time resolved reflectivity measurements. This experimental investigation revealed modifications of the heating/cooling cycle as a function of the fluence (F). These modifications start appearing for a fluence value of about {approx}0.25 J/cm{sup 2} which is associated with the melting threshold of the film. Additionally, we have solved numerically the heat equation of the system with specific boundary conditions. From these calculations, we have established the thermal history of the film during the 25 ns irradiation pulse. The data reveal that a part of the medium liquefies around a fluence of 0.23 J/cm{sup 2} in good agreement with the experimental data.

  9. A Simple and Fast Iterative Soft-thresholding Algorithm for Tight Frames in Compressed Sensing Magnetic Resonance Imaging

    E-Print Network [OSTI]

    Liu, Yunsong; Cai, Jian-Feng; Guo, Di; Chen, Zhong; Qu, Xiaobo

    2015-01-01T23:59:59.000Z

    Compressed sensing has shown great potentials in accelerating magnetic resonance imaging. Fast image reconstruction and high image quality are two main issues faced by this new technology. It has been shown that, redundant image representations, e.g. tight frames, can significantly improve the image quality. But how to efficiently solve the reconstruction problem with these redundant representation systems is still challenging. This paper attempts to address the problem of applying fast iterative soft-thresholding algorithm (FISTA) to tight frames based magnetic resonance image reconstruction. By introducing the canonical dual frame, we construct an orthogonal projection operator on the range of the analysis sparsity operator and propose a new algorithm, called the projected FISTA (pFISTA). We theoretically prove that pFISTA converges to the minimum of a function with a balanced tight frame sparsity. One major advantage of pFISTA is that only one extra parameter, the step size, is introduced and the numerical...

  10. Measurement of 3pi^0 photoproduction on the proton from threshold to 1.4 GeV

    E-Print Network [OSTI]

    Starostin, A; Nefkens, B M K; Ahrens, J; Annand, J R M; Arends, H J; Bantawa, K; Bartolome, P A; Beck, R; Bekrenev, V; Braghieri, A; Branford, D; Briscoe, W J; Brudvik, J; Cherepnya, S; Dieterle, M; Downie, E J; Fil'kov, L V; Glazier, D I; Gregor, R; Heid, E; Hornidge, D; Jaegle, I; Jahn, O; Jude, T C; Kashevarov, V L; Keshelashvili, I; Kondratiev, R; Korolija, M; Koulbardis, A; Kruglov, S; Krusche, B; Lisin, V; Livingston, K; MacGregor, I J D; Manley, D M; Martinez, M; McGeorge, J C; McNicoll, E F; Metag, V; Mushkarenkov, A; Oberle, M; Ostrick, M; Pedroni, P; Polonski, A; Prakhov, S; Robinson, J; Rosner, G; Rostomyan, T; Schumann, S; Sikora, M H; Sober, D; Supek, I; Thiel, M; Thomas, A; Unverzagt, M; Watts, D P; Wertmueller, D; Witthauer, L

    2011-01-01T23:59:59.000Z

    The total cross section for gamma p -> 3pi0 p has been measured for the first time from threshold to 1.4 GeV using the tagged photon beam of the Mainz Microtron. The equipment utilized the Crystal Ball multiphoton spectrometer, the TAPS forward detector and a particle identification detector. The gamma p -> 3pi0 p total cross section has two broad enhancements at sqrt{s}~1.5 GeV and 1.7 GeV. We obtained the ratio of the total cross sections gamma p -> 3pi0 p to gamma p -> eta p equal to 0.014 \\pm 0.001 at sqrt{s}~1.5 GeV.

  11. Measurement of 3pi^0 photoproduction on the proton from threshold to 1.4 GeV

    E-Print Network [OSTI]

    A. Starostin; I. M. Suarez; B. M. K. Nefkens; J. Ahrens; J. R. M. Annand; H. J. Arends; K. Bantawa; P. A. Bartolome; R. Beck; V. Bekrenev; A. Braghieri; D. Branford; W. J. Briscoe; J. Brudvik; S. Cherepnya; M. Dieterle; E. J. Downie; L. V. Fil'kov; D. I. Glazier; R. Gregor; E. Heid; D. Hornidge; I. Jaegle; O. Jahn; T. C. Jude; V. L. Kashevarov; I. Keshelashvili; R. Kondratiev; M. Korolija; A. Koulbardis; S. Kruglov; B. Krusche; V. Lisin; K. Livingston; I. J. D. MacGregor; D. M. Manley; M. Martinez; J. C. McGeorge; E. F. McNicoll; V. Metag; A. Mushkarenkov; M. Oberle; M. Ostrick; P. Pedroni; A. Polonski; S. Prakhov; J. Robinson; G. Rosner; T. Rostomyan; S. Schumann; M. H. Sikora; D. Sober; I. Supek; M. Thiel; A. Thomas; M. Unverzagt; D. P. Watts; D. Wertmueller; L. Witthauer

    2011-01-19T23:59:59.000Z

    The total cross section for gamma p -> 3pi0 p has been measured for the first time from threshold to 1.4 GeV using the tagged photon beam of the Mainz Microtron. The equipment utilized the Crystal Ball multiphoton spectrometer, the TAPS forward detector and a particle identification detector. The gamma p -> 3pi0 p total cross section has two broad enhancements at sqrt{s}~1.5 GeV and 1.7 GeV. We obtained the ratio of the total cross sections gamma p -> 3pi0 p to gamma p -> eta p equal to 0.014 \\pm 0.001 at sqrt{s}~1.5 GeV.

  12. Threshold Photoelectron Photoion Coincidence (TPEPICO) Studies: The Road to ? 0.1 kJ/mol Thermochemistry

    SciTech Connect (OSTI)

    Baer, Tomas [University of North Carolina

    2013-10-14T23:59:59.000Z

    The threshold photoelectron photoion coincidence (TPEPICO) technique is utilized to investigate the dissociation dynamics and thermochemistry of energy selected medium to large organic molecular ions. The reactions include parallel and consecutive steps that are modeled with the statistical theory in order to extract dissociation onsets for multiple dissociation paths. These studies are carried out with the aid of molecular orbital calculations of both ions and the transition states connecting the ion structure to their products. The results of these investigations yield accurate heats of formation of ions, free radicals, and stable molecules. In addition, they provide information about the potential energy surface that governs the dissociation process. Isomerization reactions prior to dissociation are readily inferred from the TPEPICO data.

  13. Multiple colliding electromagnetic pulses: a way to lower the threshold of $e^+e^-$ pair production from vacuum

    E-Print Network [OSTI]

    S. S. Bulanov; V. D. Mur; N. B. Narozhny; J. Nees; V. S. Popov

    2010-03-12T23:59:59.000Z

    The scheme of simultaneous multiple pulse focusing on one spot naturally arises from the structural features of projected new laser systems, such as ELI and HiPER. It is shown that the multiple pulse configuration is beneficial for observing $e^+e^-$ pair production from vacuum under the action of sufficiently strong electromagnetic fields. The field of the focused pulses is described using a realistic three-dimensional model based on an exact solution of the Maxwell equations. The $e^+e^-$ pair production threshold in terms of electromagnetic field energy can be substantially lowered if, instead of one or even two colliding pulses, multiple pulses focused on one spot are used. The multiple pulse interaction geometry gives rise to subwavelength field features in the focal region. These features result in the production of extremely short $e^+e^-$ bunches.

  14. Remote Method Invocation Remote Method Invocation

    E-Print Network [OSTI]

    Hao, Jin-Kao

    Remote Method Invocation Remote Method Invocation Jean-Michel Richer jean-michel.richer@univ-angers.fr http://www.info.univ-angers.fr/pub/richer M2 Informatique 2010-2011 1 / 22 #12;Remote Method Invocation Plan Plan 1 Introduction 2 RMI en d´etails 3 Exemple 4 Application 2 / 22 #12;Remote Method Invocation

  15. Method and system for turbomachinery surge detection

    SciTech Connect (OSTI)

    Faymon, David K.; Mays, Darrell C.; Xiong, Yufei

    2004-11-23T23:59:59.000Z

    A method and system for surge detection within a gas turbine engine, comprises: measuring the compressor discharge pressure (CDP) of the gas turbine over a period of time; determining a time derivative (CDP.sub.D ) of the measured (CDP) correcting the CDP.sub.D for altitude, (CDP.sub.DCOR); estimating a short-term average of CDP.sub.DCOR.sup.2 ; estimating a short-term average of CDP.sub.DCOR ; and determining a short-term variance of corrected CDP rate of change (CDP.sub.roc) based upon the short-term average of CDP.sub.DCOR and the short-term average of CDP.sub.DCOR.sup.2. The method and system then compares the short-term variance of corrected CDP rate of change with a pre-determined threshold (CDP.sub.proc) and signals an output when CDP.sub.roc >CDP.sub.proc. The method and system provides a signal of a surge within the gas turbine engine when CDP.sub.roc remains>CDP.sub.proc for pre-determined period of time.

  16. Fusion rules and the Patera-Sharp generating-function method

    E-Print Network [OSTI]

    L. Begin; C. Cummins; P. Mathieu; M. A. Walton

    2002-10-18T23:59:59.000Z

    We review some contributions on fusion rules that were inspired by the work of Sharp, in particular, the generating-function method for tensor-product coefficients that he developed with Patera. We also review the Kac-Walton formula, the concepts of threshold level, fusion elementary couplings, fusion generating functions and fusion bases. We try to keep the presentation elementary and exemplify each concept with the simple $\\su(2)_k$ case.

  17. DAKOTA reliability methods applied to RAVEN/RELAP-7.

    SciTech Connect (OSTI)

    Swiler, Laura Painton; Mandelli, Diego [Idaho National Laboratory, Idaho Falls, ID; Rabiti, Cristian [Idaho National Laboratory, Idaho Falls, ID; Alfonsi, Andrea [Idaho National Laboratory, Idaho Falls, ID

    2013-09-01T23:59:59.000Z

    This report summarizes the result of a NEAMS project focused on the use of reliability methods within the RAVEN and RELAP-7 software framework for assessing failure probabilities as part of probabilistic risk assessment for nuclear power plants. RAVEN is a software tool under development at the Idaho National Laboratory that acts as the control logic driver and post-processing tool for the newly developed Thermal-Hydraulic code RELAP-7. Dakota is a software tool developed at Sandia National Laboratories containing optimization, sensitivity analysis, and uncertainty quantification algorithms. Reliability methods are algorithms which transform the uncertainty problem to an optimization problem to solve for the failure probability, given uncertainty on problem inputs and a failure threshold on an output response. The goal of this work is to demonstrate the use of reliability methods in Dakota with RAVEN/RELAP-7. These capabilities are demonstrated on a demonstration of a Station Blackout analysis of a simplified Pressurized Water Reactor (PWR).

  18. Parametrization of gamma-ray production cross-sections for pp interactions in a broad proton energy range from the kinematic threshold to PeV energies

    E-Print Network [OSTI]

    Ervin Kafexhiu; Felix Aharonian; Andrew M. Taylor; Gabriela S. Vila

    2014-07-05T23:59:59.000Z

    Using publicly available Monte Carlo codes as well as compilation of published data on p--p interactions for proton kinetic energy below 2 GeV, we parametrize the energy spectra and production rates of $\\gamma$-rays by simple but quite accurate ($\\leq 20 \\%$) analytical expressions in a broad range from the kinematic threshold to PeV energies.

  19. Evidence for a Narrow Near-Threshold Structure in the J/ psi phi Mass Spectrum in B+-->J/ psi phi K+ Decays

    E-Print Network [OSTI]

    Xie, Si

    Evidence is reported for a narrow structure near the J/?? threshold in exclusive B+?J/??K+ decays produced in (p)over-bar p collisions at ?s=1.96??TeV. A signal of 14±5 events, with statistical significance in excess of ...

  20. Optical Nonlinearity in Ar and N2 near the Ionization Threshold J. K. Wahlstrand, Y.-H. Cheng, Y.-H. Chen, and H. M. Milchberg

    E-Print Network [OSTI]

    Milchberg, Howard

    Optical Nonlinearity in Ar and N2 near the Ionization Threshold J. K. Wahlstrand, Y.-H. Cheng, Y measure the nonlinear optical response in argon and nitrogen in a thin gas target to laser intensities.103901 PACS numbers: 42.65.An, 42.65.Jx, 42.65.Re The optical Kerr effect, the intensity-dependent refrac

  1. High Efficiency Oxide-Confined High-Index-Contrast Broad-Area Lasers with Reduced Threshold Current Density and Improved Near-Field Profile

    E-Print Network [OSTI]

    Bowers, John

    High Efficiency Oxide-Confined High-Index-Contrast Broad-Area Lasers with Reduced Threshold Current. The poor lateral electrical and optical confinement, however, make current spreading unavoidable and lead), followed by non-selective O2-enhanced wet thermal oxidation [2] to grow a uniform thickness layer of high

  2. IEEE TRANSACTIONS ON BIO-MEDICAL ENGINEERINNG, VOL. BME-18, NO. 4, JULY 1971 HEWLETTP p , C ag Ultrasonic Threshold Dosages for the Mammalan

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    , and human central nervous systems are presented for a wide range of the pertinent parameters. There does of commercially avail- able ultrasonic diagnostic instruments, the experimentally deter- mined threshold dosages, Ohio, October 15, 1970. The authors are with Bioacoustics Research Laboratory, Univer- sity of Illinois

  3. PHYSICAL REVIEW A 87, 023407 (2013) Multiphoton above-threshold ionization in superintense free-electron x-ray laser fields

    E-Print Network [OSTI]

    Chu, Shih-I

    2013-01-01T23:59:59.000Z

    . INTRODUCTION With the recent development of free-electron lasers (FELs), particularly the "fourthPHYSICAL REVIEW A 87, 023407 (2013) Multiphoton above-threshold ionization in superintense free-electron successfully used to investigate the multiphoton processes of a hydrogen atom exposed to superintense free-electron

  4. Measured hot-electron intensity thresholds quantified by a two-plasmon-decay resonant common-wave gain in various experimental configurations

    SciTech Connect (OSTI)

    Michel, D. T.; Maximov, A. V.; Short, R. W.; Delettrez, J. A.; Edgell, D.; Hu, S. X.; Igumenshchev, I. V.; Myatt, J. F.; Solodov, A. A.; Stoeckl, C.; Yaakobi, B.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14636 (United States)] [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14636 (United States)

    2013-05-15T23:59:59.000Z

    The fraction of laser energy converted into hot electrons by the two-plasmon-decay instability is found to have different overlapped intensity thresholds for various configurations on the Omega Laser Facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997); J. H. Kelly et al., J. Phys. IV 133, 75 (2006)]. A factor-of-2 difference in the overlapped intensity threshold is observed between two- and four-beam configurations. The overlapped intensity threshold increases by a factor of 2 between the 4- and 18-beam configurations and by a factor of 3 between the 4- and 60-beam configurations. This is explained by a linear common-wave model where multiple laser beams drive a common electron-plasma wave in a wavevector region that bisects the laser beams (resonant common-wave region in k-space). These experimental results indicate that the hot-electron threshold depends on the hydrodynamic parameters at the quarter-critical density surface, the configuration of the laser beams, and the sum of the intensity of the beams that share the same angle with the common-wave vector.

  5. Evaluation of the threshold of stability for the human spine Martin L. Tanaka a,b,d,, Maury A. Nussbaum b,c

    E-Print Network [OSTI]

    Ross, Shane

    stability Kinematic variability Low back pain a b s t r a c t The threshold of stability (ToS) is introduced of the ToS to changes in postural control using visual feedback as a control variable. The ToS was found in which minimal instrumentation is needed. Its simplicity, sensitivity, and low cost suggest that the ToS

  6. Parametrization of the increase of the aeolian erosion threshold wind friction velocity due to soil moisture for arid and semi-arid areas

    E-Print Network [OSTI]

    Boyer, Edmond

    partition scheme (in which the wind energy is transfered to the erodible surface as a functionParametrization of the increase of the aeolian erosion threshold wind friction velocity due to soil February 1998 / Revised: 11 May 1998 / Accepted: 25 May 1998 Abstract. Large-scale simulation of the soil

  7. GaN nanowire lasers with low lasing thresholds Silvija Gradecak, Fang Qian, Yat Li, Hong-Gyu Park, and Charles M. Liebera

    E-Print Network [OSTI]

    Li, Yat

    GaN nanowire lasers with low lasing thresholds Silvija Gradecak, Fang Qian, Yat Li, Hong-Gyu Park September 2005; published online 18 October 2005 We report optically pumped room-temperature lasing in GaN of 22 kW/cm2 that are substantially lower than other previously reported GaN nanowires. Key

  8. SUBJECT: Increase in Equipment Capitalization Threshold to $5,000 As of July 1, 2011 the Florida Board of Governors approved BOG Regulation 9.001, 9.002, 9.003

    E-Print Network [OSTI]

    Fernandez, Eduardo

    resources greater than $250 all have been capitalized. As of July 1, 2011 the threshold is increased from personal property items with a cost of greater $5,000 and library resources with a cost greater than $250SUBJECT: Increase in Equipment Capitalization Threshold to $5,000 As of July 1, 2011 the Florida

  9. High-power, very low threshold, GaImnP/AIGaInP visble-diode lasers l-l. B. Serreze, v. C. Chen, and R. 6. Waters

    E-Print Network [OSTI]

    lasers,and this cw threshold current density is believedto be, by far, the lowest. Low-power visibleHigh-power, very low threshold, GaImnP/AIGaInP visble-diode lasers l-l. B. Serreze, v. C. Chen light (665 nm) laser diodesemploying a strained-layer,single quantum well, graded index

  10. High-energy threshold reaction rates on 0.8 GeV proton-irradiated thick Pb-target

    E-Print Network [OSTI]

    Yu. E. Titarenko; V. F. Batyaev; A. Yu. Titarenko; M. A. Butko; K. V. Pavlov; R. S. Tikhonov; S. N. Florya; S. G. Mashnik; W. Gudowski

    2007-05-08T23:59:59.000Z

    This works presents results of activation-aided determination of threshold reaction rates in 92 209Bi, natPb, 197Au, 181Ta, 169Tm, natIn, 93Nb, 64Zn, 65Cu, 63Cu, 59Co, 19F, and 12C samples and in 121 27Al samples. All the samples were aligned with the proton beam axis inside and outside the demountable 92-cm thick Pb target of 15-cm diameter assembled of 23 4-cm thick discs. The samples were placed on 12 target disks to reproduce the long axis distribution of protons and neutrons. In June 2006, the target was exposed for 18 hours to a 800-MeV proton beam extracted from the ITEP U-10 accelerator. The proton fluence and the proton beam shape were determined using the 27Al(p,x)7Be monitor reaction. The reaction rates were determined by the direct gamma-spectrometry techniques. In total, 1196 gamma-spectra have been measured, and about 1500 reaction rates determined. The measured reaction rates were simulated by the MCNPX code using the following databases: ENDF/B6 for neutrons below 20 MeV, MENDL2 for 20-100 MeV neutrons, and MENDL2P for proton cross sections up to 200 MeV. An acceptable agreement of simulations with experimental data has been found.

  11. A semi-analytic power balance model for low (L) to high (H) mode transition power threshold

    SciTech Connect (OSTI)

    Singh, R., E-mail: rsingh129@yahoo.co.in [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Institute for Plasma Research, Bhat Gandhinagar 2382 428 (India); Jhang, Hogun [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Kaw, P. K. [Institute for Plasma Research, Bhat Gandhinagar 2382 428 (India); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093 (United States); Center for Astrophysics and Space Sciences, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093-0424 (United States); Nordman, H. [Department of Earth and Space Sciences, Chalmers University of Technology, SE-412 96 Göteborg (Sweden); Bourdelle, C. [Euratom-CEA Association, CEA/DSM/DRFC, CEA Cadarache F-13108 Saint-Paul-Lez-Durance (France); Loarte, A. [ITER Organization, Route de Vinon Sur Verdon, A. 13115 Saint Paul Lez Durance (France)

    2014-06-15T23:59:59.000Z

    We present a semi-analytic model for low (L) to high (H) mode transition power threshold (P{sub th}). Two main assumptions are made in our study. First, high poloidal mode number drift resistive ballooning modes (high-m DRBM) are assumed to be the dominant turbulence driver in a narrow edge region near to last closed flux surface. Second, the pre-transition edge profile and turbulent diffusivity at the narrow edge region pertain to turbulent equipartition. An edge power balance relation is derived by calculating the dissipated power flux through both turbulent conduction and convection, and radiation in the edge region. P{sub th} is obtained by imposing the turbulence quench rule due to sheared E?×?B rotation. Evaluation of P{sub th} shows a good agreement with experimental results in existing machines. Increase of P{sub th} at low density (i.e., the existence of roll-over density in P{sub th} vs. density) is shown to originate from the longer scale length of the density profile than that of the temperature profile.

  12. Investigation of stimulated raman scattering using short-pulse diffraction limited laser beam near the instability threshold

    SciTech Connect (OSTI)

    Kline, John L [Los Alamos National Laboratory; Montgomery, David S [Los Alamos National Laboratory; Flippo, Kirk A [Los Alamos National Laboratory; Rose, Harvey A [Los Alamos National Laboratory; Yin, L [Los Alamos National Laboratory; Albright, B J [Los Alamos National Laboratory; Johnson, R P [Los Alamos National Laboratory; Shimada, T [Los Alamos National Laboratory; Bowers, K [Los Alamos National Laboratory; Rousseaux, C [CEA; Tassin, V [CEA; Baton, S D [FRANCE; Amiranoff, F [FRANCE; Hardin, R A [WEST VIRGINIA UNIV

    2008-01-01T23:59:59.000Z

    Short pulse laser plasma interaction experiments using diffraction limited beams provide an excellent platform to investigate the fundamental physics of Stimulated Raman Scattering. Detailed understanding of these laser plasma instabilities impacts the current inertial confinement fusion ignition designs and could potentially impact fast ignition when higher energy lasers are used with longer pulse durations ( > 1 kJ and> 1 ps). Using short laser pulses, experiments can be modeled over the entire interaction time of the laser using particle-in-cell codes to validate our understanding quantitatively. Experiments have been conducted at the Trident laser facility and the LULI (Laboratoire pour l'Utilisation des Lasers Intenses) to investigate stimulated Raman scattering near the threshold of the instability using 527 nm and 1059 nm laser light respectively with 1.5-3.0 ps pulses. In both experiments, the interaction beam was focused into a pre-ionized He gas-jet plasma. Measurements of the reflectivity as a function of intensity and k{lambda}{sub D} were completed at the Trident laser facility. At LULI, a 300 fs Thomson scattering probe is used to directly measure the density fluctuations of the driven electron plasma and ion acoustic waves. Work is currently underway comparing the results of the experiments with simulations using the VPIC [K. J. Bowers, et at., Phys. Plasmas, 15 055703 (2008)] particle-in-cell code. Details of the experimental results are presented in this manuscript.

  13. Cancer-associated p53 tetramerization domain mutants: quantitative analysis reveals a low threshold for tumor suppressor inactivation

    SciTech Connect (OSTI)

    Kamada, R.; Anderson, C.; Nomura, T.; Sakaguchi, K.

    2011-01-07T23:59:59.000Z

    The tumor suppressor p53, a 393-amino acid transcription factor, induces cell cycle arrest and apoptosis in response to genotoxic stress. Its inactivation via the mutation of its gene is a key step in tumor progression, and tetramer formation is critical for p53 post-translational modification and its ability to activate or repress the transcription of target genes vital in inhibiting tumor growth. About 50% of human tumors have TP53 gene mutations; most are missense ones that presumably lower the tumor suppressor activity of p53. In this study, we explored the effects of known tumor-derived missense mutations on the stability and oligomeric structure of p53; our comprehensive, quantitative analyses encompassed the tetramerization domain peptides representing 49 such substitutions in humans. Their effects on tetrameric structure were broad, and the stability of the mutant peptides varied widely ({Delta}T{sub m} = 4.8 {approx} -46.8 C). Because formation of a tetrameric structure is critical for protein-protein interactions, DNA binding, and the post-translational modification of p53, a small destabilization of the tetrameric structure could result in dysfunction of tumor suppressor activity. We suggest that the threshold for loss of tumor suppressor activity in terms of the disruption of the tetrameric structure of p53 could be extremely low. However, other properties of the tetramerization domain, such as electrostatic surface potential and its ability to bind partner proteins, also may be important.

  14. Method for nonlinear optimization for gas tagging and other systems

    DOE Patents [OSTI]

    Chen, T.; Gross, K.C.; Wegerich, S.

    1998-01-06T23:59:59.000Z

    A method and system are disclosed for providing nuclear fuel rods with a configuration of isotopic gas tags. The method includes selecting a true location of a first gas tag node, selecting initial locations for the remaining n-1 nodes using target gas tag compositions, generating a set of random gene pools with L nodes, applying a Hopfield network for computing on energy, or cost, for each of the L gene pools and using selected constraints to establish minimum energy states to identify optimal gas tag nodes with each energy compared to a convergence threshold and then upon identifying the gas tag node continuing this procedure until establishing the next gas tag node until all remaining n nodes have been established. 6 figs.

  15. Method for nonlinear optimization for gas tagging and other systems

    DOE Patents [OSTI]

    Chen, Ting (Chicago, IL); Gross, Kenny C. (Bolingbrook, IL); Wegerich, Stephan (Glendale Heights, IL)

    1998-01-01T23:59:59.000Z

    A method and system for providing nuclear fuel rods with a configuration of isotopic gas tags. The method includes selecting a true location of a first gas tag node, selecting initial locations for the remaining n-1 nodes using target gas tag compositions, generating a set of random gene pools with L nodes, applying a Hopfield network for computing on energy, or cost, for each of the L gene pools and using selected constraints to establish minimum energy states to identify optimal gas tag nodes with each energy compared to a convergence threshold and then upon identifying the gas tag node continuing this procedure until establishing the next gas tag node until all remaining n nodes have been established.

  16. Systems and methods for initializing a charging system

    DOE Patents [OSTI]

    Ransom, Ray M.; Perisic, Milun; Kajouke, Lateef A.

    2014-09-09T23:59:59.000Z

    Systems and methods are provided for initiating a charging system. The method, for example, may include, but is not limited to, providing, by the charging system, an incrementally increasing voltage to a battery up to a first predetermined threshold while the energy conversion module has a zero-percent duty cycle, providing, by the charging system, an incrementally increasing voltage to the battery from an initial voltage level of the battery up to a peak voltage of a voltage source while the energy conversion module has a zero-percent duty cycle, and providing, by the charging system, an incrementally increasing voltage to the battery by incrementally increasing the duty cycle of the energy conversion module.

  17. Systems and methods for initializing a charging system

    DOE Patents [OSTI]

    Ransom, Ray M; Perisic, Milun; Kajouke, Lateef A

    2014-06-24T23:59:59.000Z

    Systems and methods are provided for initiating a charging system. The method, for example, may include, but is not limited to, providing, by the charging system, an incrementally increasing voltage to a battery up to a first predetermined threshold while the energy conversion module has a zero-percent duty cycle, providing, by the charging system, an incrementally increasing voltage to the battery from an initial voltage level of the battery up to a peak voltage of a voltage source while the energy conversion module has a zero-percent duty cycle, and providing, by the charging system, an incrementally increasing voltage to the battery by incrementally increasing the duty cycle of the energy conversion module.

  18. Physics-based, Bayesian sequential detection method and system for radioactive contraband

    DOE Patents [OSTI]

    Candy, James V; Axelrod, Michael C; Breitfeller, Eric F; Chambers, David H; Guidry, Brian L; Manatt, Douglas R; Meyer, Alan W; Sale, Kenneth E

    2014-03-18T23:59:59.000Z

    A distributed sequential method and system for detecting and identifying radioactive contraband from highly uncertain (noisy) low-count, radionuclide measurements, i.e. an event mode sequence (EMS), using a statistical approach based on Bayesian inference and physics-model-based signal processing based on the representation of a radionuclide as a monoenergetic decomposition of monoenergetic sources. For a given photon event of the EMS, the appropriate monoenergy processing channel is determined using a confidence interval condition-based discriminator for the energy amplitude and interarrival time and parameter estimates are used to update a measured probability density function estimate for a target radionuclide. A sequential likelihood ratio test is then used to determine one of two threshold conditions signifying that the EMS is either identified as the target radionuclide or not, and if not, then repeating the process for the next sequential photon event of the EMS until one of the two threshold conditions is satisfied.

  19. Methods for improved forewarning of condition changes in monitoring physical processes

    DOE Patents [OSTI]

    Hively, Lee M.

    2013-04-09T23:59:59.000Z

    This invention teaches further improvements in methods for forewarning of critical events via phase-space dissimilarity analysis of data from biomedical equipment, mechanical devices, and other physical processes. One improvement involves objective determination of a forewarning threshold (U.sub.FW), together with a failure-onset threshold (U.sub.FAIL) corresponding to a normalized value of a composite measure (C) of dissimilarity; and providing a visual or audible indication to a human observer of failure forewarning and/or failure onset. Another improvement relates to symbolization of the data according the binary numbers representing the slope between adjacent data points. Another improvement relates to adding measures of dissimilarity based on state-to-state dynamical changes of the system. And still another improvement relates to using a Shannon entropy as the measure of condition change in lieu of a connected or unconnected phase space.

  20. Universiteit Antwerpen Research Methods

    E-Print Network [OSTI]

    Nierstrasz, Oscar

    Methods Science vs. Engineering 5 Science Engineering Physics Chemistry Biology Mathematics ElectroUniversiteit Antwerpen Research Methods in Computer Science (Serge Demeyer -- University of Antwerp Introduction · Origins of Computer Science · Research Philosophy Research Methods · Feasibility study · Pilot

  1. Introduction Conjugate Gradient Method

    E-Print Network [OSTI]

    Vuik, Kees

    Introduction Conjugate Gradient Method Deflation Domain Decomposition Research Master Thesis Presentation #12;Introduction Conjugate Gradient Method Deflation Domain Decomposition Research Plaxis Finite Kaliszka Master Thesis Literature Study Presentation #12;Introduction Conjugate Gradient Method Deflation

  2. Hydrogen Threshold Cost Calculation

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of Blythe SolarContaminationCurrent Technology »Clean Coal » CoalProgram

  3. Threshold Reflectivity Zc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2, 2003 (Next ReleaseThomasTheories |20 -18 -16 -14

  4. Method Of Charging Maintenance-Free Nickel Metal Hydride Storage Cells

    DOE Patents [OSTI]

    Berlureau, Thierry (Bordeaux, FR); Liska, Jean-Louis (Bordeaux, FR)

    1999-11-16T23:59:59.000Z

    A method of charging an industrial maintenance-free Ni-MH storage cell, the method comprising in combination a first stage at a constant current I.sub.1 lying in the range I.sub.c /10 to I.sub.c /2, and a second stage at a constant current I.sub.2 lying in the range I.sub.c /50 to I.sub.c /10, the changeover from the first stage to the second stage taking place when the time derivative of the temperature reaches a threshold value which varies as a function of the temperature at the time of the changeover.

  5. Effect of quantum well non-uniformities on lasing threshold, linewidth, and lateral near field filamentation in violet (Al,In)GaN laser diodes

    SciTech Connect (OSTI)

    Jeschke, J.; Zeimer, U.; Redaelli, L.; Einfeldt, S.; Weyers, M. [Ferdinand-Braun-Institut, Leibniz-Institut fuer Hoechstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin (Germany); Kneissl, M. [Ferdinand-Braun-Institut, Leibniz-Institut fuer Hoechstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin (Germany); Institute of Solid State Physics, Technical University of Berlin, 10623 Belin (Germany)

    2014-10-27T23:59:59.000Z

    The lateral near field patterns and filamentation effects of gain guided broad area (Al,In)GaN-based laser diodes emitting around 415?nm have been investigated. Diodes from the same laser bar, which are close to each other, show nearly the same number and widths of filaments. Comparison of different bars, which are from the same wafer but further apart from each other, reveals that a higher number of filaments correlates with a higher laser threshold and broader spectral linewidth. Cathodoluminescence mappings at 80?K show strong variations of the quantum well band gap and hence of the emission wavelength for the bars with strong filamentation. These observations confirm previous theoretical predictions stating that large band gap fluctuations increase the threshold current and spectral linewidth. Furthermore, filamentation is enhanced as well because of a reduction of the carrier diffusion length.

  6. Anomalous reduction of the switching voltage of Bi-doped Ge{sub 0.5}Se{sub 0.5} ovonic threshold switching devices

    SciTech Connect (OSTI)

    Seo, Juhee [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 305-350 (Korea, Republic of); Ahn, Hyung-Woo [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Material Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Shin, Sang-yeol [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Materials Science and Engineering, Korea Aerospace University, Goyang 412-791 (Korea, Republic of); Cheong, Byung-ki; Lee, Suyoun, E-mail: slee-eels@kist.re.kr [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of)

    2014-04-14T23:59:59.000Z

    Switching devices based on Ovonic Threshold Switching (OTS) have been considered as a solution to overcoming limitations of Si-based electronic devices, but the reduction of switching voltage is a major challenge. Here, we investigated the effect of Bi-doping in Ge{sub 0.5}Se{sub 0.5} thin films on their thermal, optical, electrical properties, as well as on the characteristics of OTS devices. As Bi increased, it was found that both of the optical energy gap (E{sub g}{sup opt}) and the depth of trap states decreased resulting in a drastic reduction of the threshold voltage (V{sub th}) by over 50%. In addition, E{sub g}{sup opt} was found to be about three times of the conduction activation energy for each composition. These results are explained in terms of the Mott delocalization effect by doping Bi.

  7. High-speed digital modulation of ultralow threshold (<1 mA) GaAs single quantum well lasers without bias

    SciTech Connect (OSTI)

    Lau, K.Y.; Bar-Chaim, N.; Derry, P.L.; Yariv, A.

    1987-07-13T23:59:59.000Z

    GaAlAs buried heterostructure lasers with submilliampere threshold current fabricated from single quantum well wafers can be driven directly with logic level signals without any current bias. The switch-on delay was measured to be <50 ps and no relaxation oscillation ringing was observed. These lasers permit fully o-smcapsn-smcapsreverse arrow-smcapso-smcapsf-smcapsf-smcaps multigigabit digital switching while at the same time obviating the need for bias monitoring and feedback control.

  8. We've found an error in our paper. In the threshold signature scheme that we used, there are restrictions on the threshold value. In particular if the key is shared over a degree t polynomial, then 2t+1 players (not t+1)

    E-Print Network [OSTI]

    Singh, Jaswinder Pal

    and will be updating the paper accordingly. Securing Bitcoin wallets via threshold signatures Steven Goldfeder stevenag@cs.princeton.edu Arvind Narayanan arvindn@cs.princeton.edu ABSTRACT The Bitcoin ecosystem has suffered frequent thefts serious. Due to the irre- versibility, automation, and pseudonymity of transactions, Bitcoin currently

  9. Using wavelet analysis to compare the QCD prediction and experimental data on $R_{e^+e^-}$ and to determine parameters of the charmonium states above the $D\\bar D$ threshold

    E-Print Network [OSTI]

    Henner, V K; Belozerova, T S

    2015-01-01T23:59:59.000Z

    The first part of our analysis uses the wavelet method to compare the Quantum Chromodynamic (QCD) prediction for the ratio of hadronic to muon cross sections in electron-positron collisions, $R$, with experimental data for $R$ over a center of mass energy range up to 7.5 GeV. A direct comparison of the raw experimental data and the QCD prediction is difficult because the data have a wide range of structures and large statistical errors and the QCD description contains sharp quark-antiquark thresholds. However, a meaningful comparison can be made if a type of "smearing" procedure is used to smooth out rapid variations in both the theoretical and experimental values of $R$. A wavelet analysis (WA) can be used to achieve this smearing effect. In the second part of the analysis we concentrate on the 3.0 - 6.0 GeV energy region containing the relatively wide charmonium resonances $\\psi(1^-)$. We use the wavelet methodology to distinguish these resonances from experimental noise, background and from each other, and...

  10. Using wavelet analysis to compare the QCD prediction and experimental data on $R_{e^+e^-}$ and to determine parameters of the charmonium states above the $D\\bar D$ threshold

    E-Print Network [OSTI]

    V. K. Henner; C. L. Davis; T. S. Belozerova

    2015-06-12T23:59:59.000Z

    The first part of our analysis uses the wavelet method to compare the Quantum Chromodynamic (QCD) prediction for the ratio of hadronic to muon cross sections in electron-positron collisions, $R$, with experimental data for $R$ over a center of mass energy range up to 7.5 GeV. A direct comparison of the raw experimental data and the QCD prediction is difficult because the data have a wide range of structures and large statistical errors and the QCD description contains sharp quark-antiquark thresholds. However, a meaningful comparison can be made if a type of "smearing" procedure is used to smooth out rapid variations in both the theoretical and experimental values of $R$. A wavelet analysis (WA) can be used to achieve this smearing effect. In the second part of the analysis we concentrate on the 3.0 - 6.0 GeV energy region containing the relatively wide charmonium resonances $\\psi(1^-)$. We use the wavelet methodology to distinguish these resonances from experimental noise, background and from each other, and are thus able to determine more reliably the parameters of these states. These two analyses are examples of the usefulness of WA in extracting information in a model independent way from high energy physics data.

  11. Radiochemical method development

    SciTech Connect (OSTI)

    Erickson, M.D.; Aldstadt, J.H.; Alvarado, J.S.; Crain, J.S.; Orlandini, K.A.; Smith, L.L.

    1994-09-01T23:59:59.000Z

    The authors have developed methods for chemical characterization of the environment under a multitask project that focuses on improvement of radioanalytical methods with an emphasis on faster and cheaper routine methods. The authors have developed improved methods for separation of environmental levels of technetium-99, radium, and actinides from soil and water; separation of actinides from soil and water matrix interferences; and isolation of strontium. They are also developing methods for simultaneous detection of multiple isotopes (including nonradionuclides) by using a new instrumental technique, inductively coupled plasma-mass spectrometry (ICP-MS). The new ICP-MS methods have greater sensitivity and efficiency and could replace many radiometric techniques. They are using flow injection analysis to integrate and automate the separation methods with the ICP-MS methodology. The final product of all activities will be methods that are available (published in the U.S. Department of Energy`s analytical methods compendium) and acceptable for use in regulatory situations.

  12. Method for enhanced control of welding processes

    DOE Patents [OSTI]

    Sheaffer, Donald A. (Livermore, CA); Renzi, Ronald F. (Tracy, CA); Tung, David M. (Livermore, CA); Schroder, Kevin (Pleasanton, CA)

    2000-01-01T23:59:59.000Z

    Method and system for producing high quality welds in welding processes, in general, and gas tungsten arc (GTA) welding, in particular by controlling weld penetration. Light emitted from a weld pool is collected from the backside of a workpiece by optical means during welding and transmitted to a digital video camera for further processing, after the emitted light is first passed through a short wavelength pass filter to remove infrared radiation. By filtering out the infrared component of the light emitted from the backside weld pool image, the present invention provides for the accurate determination of the weld pool boundary. Data from the digital camera is fed to an imaging board which focuses on a 100.times.100 pixel portion of the image. The board performs a thresholding operation and provides this information to a digital signal processor to compute the backside weld pool dimensions and area. This information is used by a control system, in a dynamic feedback mode, to automatically adjust appropriate parameters of a welding system, such as the welding current, to control weld penetration and thus, create a uniform weld bead and high quality weld.

  13. Critical Parameters for Turbulent Transport in the SOL: Mechanism for the L-H Transition and its impact on the H-mode Power Threshold and Density Limit in ITER

    E-Print Network [OSTI]

    Critical Parameters for Turbulent Transport in the SOL: Mechanism for the L-H Transition and its impact on the H-mode Power Threshold and Density Limit in ITER

  14. ENVIRONMENTAL PHYSICS METHODS

    E-Print Network [OSTI]

    Horváth, Ákos

    , environmental radiation, noise, acustics, infra sound, natural radioactivity, solar energy, polarized lightENVIRONMENTAL PHYSICS METHODS LABORATORY PRACTICES #12;Foundations of Environmental Science Lecture Enviromental Physics Methods Laboratory Practices #12;Eötvös Loránd University Faculty of Science ENVIRONMENTAL

  15. Method of intrinsic marking

    DOE Patents [OSTI]

    Adams, David P; McDonald, Joel Patrick; Jared, Bradley Howell; Hodges, V. Carter; Hirschfeld, Deidre; Blair, Dianna S

    2014-04-01T23:59:59.000Z

    A method of pulsed laser intrinsic marking can provide a unique identifier to detect tampering or counterfeiting.

  16. FORMED 2008 Formal Methods

    E-Print Network [OSTI]

    Gibson, J. Paul

    - puter science in schools. Formal methods bridge the boundary between computing and mathematics of computer science as a discipline in its own right. We give concrete examples of the type of formal methods formal methods in schools? The current state of mathematics teaching around the world is causing prob

  17. Combustible structural composites and methods of forming combustible structural composites

    DOE Patents [OSTI]

    Daniels, Michael A. (Idaho Falls, ID); Heaps, Ronald J. (Idaho Falls, ID); Steffler, Eric D (Idaho Falls, ID); Swank, William D. (Idaho Falls, ID)

    2011-08-30T23:59:59.000Z

    Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

  18. Combustible structural composites and methods of forming combustible structural composites

    DOE Patents [OSTI]

    Daniels, Michael A.; Heaps, Ronald J.; Steffler, Eric D.; Swank, W. David

    2013-04-02T23:59:59.000Z

    Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

  19. Method using a density field for locating related items for data mining

    DOE Patents [OSTI]

    Wylie, Brian N. (Albuquerque, NM)

    2002-01-01T23:59:59.000Z

    A method for locating related items in a geometric space transforms relationships among items to geometric locations. The method locates items in the geometric space so that the distance between items corresponds to the degree of relatedness. The method facilitates communication of the structure of the relationships among the items. The method makes use of numeric values as a measure of similarity between each pairing of items. The items are given initial coordinates in the space. An energy is then determined for each item from the item's distance and similarity to other items, and from the density of items assigned coordinates near the item. The distance and similarity component can act to draw items with high similarities close together, while the density component can act to force all items apart. If a terminal condition is not yet reached, then new coordinates can be determined for one or more items, and the energy determination repeated. The iteration can terminate, for example, when the total energy reaches a threshold, when each item's energy is below a threshold, after a certain amount of time or iterations.

  20. Study of digital pulse shape discrimination method for n-? separation of EJ-301 liquid scintillation detector

    E-Print Network [OSTI]

    Bo Wan; Xueying Zhang; Liang Chen; Honglin Ge; Fei Ma; Hongbin Zhang; Yongqin Ju; Yanbin Zhang; Yanyan Li; Xiaowei Xu

    2015-02-06T23:59:59.000Z

    A digital pulse shape discrimination system based on a programmable module NI-5772 has been established and tested with EJ-301 liquid scintillation detector. The module was operated by means of running programs developed in LabVIEW with the sampling frequency up to 1.6GS/s. Standard gamma sources 22Na, 137Cs and 60Co were used to calibrate the EJ-301 liquid scintillation detector, and the gamma response function has been obtained. Digital algorithms for charge comparison method and zero-crossing method have been developed. The experimental results showed that both digital signal processing (DSP) algorithms could discriminate neutrons from gamma-rays. Moreover, the zero-crossing method shows better n-{\\gamma} discrimination at 80 keVee and lower, whereas the charge comparison method gives better results at higher thresholds. In addition, the figure-of-merit (FOM) of two different dimension detectors were extracted at 9 energy thresholds, and it was found that the smaller one presented a better n-{\\gamma} separation property for fission neutrons.

  1. Observation of a Near-Threshold {omega}J/{psi} Mass Enhancement in Exclusive B{yields}K{omega}J/{psi} Decays

    SciTech Connect (OSTI)

    Choi, S.-K. [Gyeongsang National University, Chinju (Korea, Republic of); Olsen, S.L.; Browder, T.E.; Fang, F.; Trabelsi, K.; Varner, G. [University of Hawaii, Honolulu, Hawaii 96822 (United States); Abe, K.; Adachi, I.; Gershon, T.; Hastings, N.C.; Hazumi, M.; Ishikawa, A.; Iwasaki, Y.; Katayama, N.; Kichimi, H.; Nakao, M.; Nakazawa, H.; Nishida, S.; Sagawa, H.; Sakai, Y. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan)] [and others

    2005-05-13T23:59:59.000Z

    We report the observation of a near-threshold enhancement in the {omega}J/{psi} invariant mass distribution for exclusive B{yields}K{omega}J/{psi} decays. The results are obtained from a 253 fb{sup -1} data sample that contains 275x10{sup 6} BB pairs that were collected near the {upsilon}(4S) resonance with the Belle detector at the KEKB asymmetric energy e{sup +}e{sup -} collider. The statistical significance of the {omega}J/{psi} mass enhancement is estimated to be greater than 8{sigma}.

  2. Two-Source Double-Slit Interference in Angle-Resolved High-Energy Above-Threshold Ionization Spectra of Diatoms

    SciTech Connect (OSTI)

    Okunishi, M.; Itaya, R.; Shimada, K.; Pruemper, G.; Ueda, K. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Busuladzic, M. [Medical Faculty, Cekalusa 90, University of Sarajevo, 71000 Sarajevo (Bosnia and Herzegowina); Gazibegovic-Busuladzic, A. [Faculty of Science, Zmaja od Bosne 35, University of Sarajevo, 71000 Sarajevo (Bosnia and Herzegowina); Milosevic, D. B. [Faculty of Science, Zmaja od Bosne 35, University of Sarajevo, 71000 Sarajevo (Bosnia and Herzegowina); Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany); Becker, W. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Max-Born-Institut, Max-Born-Strasse 2a, 12489 Berlin (Germany)

    2009-07-24T23:59:59.000Z

    When an electron from a diatomic molecule undergoes tunneling-rescattering ionization, a novel form of destructive interference can be realized that involves all four geometric orbits that are available to the electron when it is freed, because both ionization and rescattering may take place at the same or at different centers. We find experimentally and confirm theoretically that in orientation-averaged angle-resolved high-order above-threshold ionization spectra the corresponding destructive interference is visible for O{sub 2} but not for N{sub 2}. This effect is different from the suppression of ionization that is well known to occur for O{sub 2}.

  3. Using polymer electrolyte gates to set-and-freeze threshold voltage and local potential in nanowire-based devices and thermoelectrics

    E-Print Network [OSTI]

    Sofia Fahlvik Svensson; Adam M. Burke; Damon J. Carrad; Martin Leijnse; Heiner Linke; Adam P. Micolich

    2014-11-11T23:59:59.000Z

    We use the strongly temperature-dependent ionic mobility in polymer electrolytes to 'freeze in' specific ionic charge environments around a nanowire using a local wrap-gate geometry. This enables us to set both the threshold voltage for a conventional doped substrate gate and the local disorder potential at temperatures below 200 Kelvin, which we characterize in detail by combining conductance and thermovoltage measurements with modeling. Our results demonstrate that local polymer electrolyte gates are compatible with nanowire thermoelectrics, where they offer the advantage of a very low thermal conductivity, and hold great potential towards setting the optimal operating point for solid-state cooling applications.

  4. Continuous-wave operation of extremely low-threshold GaAs/AlGaAs broad-area injection laser on (110) Si substrate at room temperature

    SciTech Connect (OSTI)

    Chen, H.Z.; Ghaffari, A.; Wang, H.; Morkoc, H.; Yariv, A.

    1987-10-01T23:59:59.000Z

    Room-temperature continuous-wave operation of large-area (120 ..mu..m x 980 ..mu..m) GaAs/AlGaAs graded-refractive-index separate-confinement heterostructure lasers on (100)Si substrates has been obtained. Minimum threshold-current densities of 214 A/cm/sup 2/ (1900-..mu..m cavity length), maximum slope efficiencies of about 0.8 W/A (600-..mu..m cavity length), and optical power in excess of 270 mW/facet (900-..mu..m cavity length) have been observed under pulsed conditions.

  5. Damage threshold and focusability of mid-infrared free-electron laser pulses gated by a plasma mirror with nanosecond switching pulses

    SciTech Connect (OSTI)

    Wang, Xiaolong; Nakajima, Takashi; Zen, Heishun; Kii, Toshiteru; Ohgaki, Hideaki [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2013-11-04T23:59:59.000Z

    The presence of a pulse train structure of an oscillator-type free-electron laser (FEL) results in the immediate damage of a solid target upon focusing. We demonstrate that the laser-induced damage threshold can be significantly improved by gating the mid-infrared FEL pulses with a plasma mirror. Although the switching pulses we employ have a nanosecond duration which does not guarantee the clean wavefront of the gated FEL pulses, the high focusability is experimentally confirmed through the observation of spectral broadening by a factor of 2.1 when we tightly focus the gated FEL pulses onto the Ge plate.

  6. Localization-delocalization transition of electrons at the percolation threshold of semiconductor GaAs1–xNx alloys: The appearance of a mobility edge

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Alberi, K.; Fluegel, B.; Beaton, D. A.; Ptak, A. J.; Mascarenhas, A.

    2012-07-01T23:59:59.000Z

    Electrons in semiconductor alloys have generally been described in terms of Bloch states that evolve from constructive interference of electron waves scattering from perfectly periodic potentials, despite the loss of structural periodicity that occurs on alloying. Using the semiconductor alloy GaAs??xNx as a prototype, we demonstrate a localized to delocalized transition of the electronic states at a percolation threshold, the emergence of a mobility edge, and the onset of an abrupt perturbation to the host GaAs electronic structure, shedding light on the evolution of electronic structure in these abnormal alloys.

  7. An adaptive multi-element generalized polynomial chaos method for stochastic differential equations

    SciTech Connect (OSTI)

    Wan Xiaoliang [Division of Applied Mathematics, Center for Fluid Mechanics, Brown University, 182 George Street, Box F, Providence, RI 02912 (United States)]. E-mail: xlwan@dam.brown.edu; Karniadakis, George Em [Division of Applied Mathematics, Center for Fluid Mechanics, Brown University, 182 George Street, Box F, Providence, RI 02912 (United States)]. E-mail: gk@dam.brown.edu

    2005-11-01T23:59:59.000Z

    We formulate a Multi-Element generalized Polynomial Chaos (ME-gPC) method to deal with long-term integration and discontinuities in stochastic differential equations. We first present this method for Legendre-chaos corresponding to uniform random inputs, and subsequently we generalize it to other random inputs. The main idea of ME-gPC is to decompose the space of random inputs when the relative error in variance becomes greater than a threshold value. In each subdomain or random element, we then employ a generalized polynomial chaos expansion. We develop a criterion to perform such a decomposition adaptively, and demonstrate its effectiveness for ODEs, including the Kraichnan-Orszag three-mode problem, as well as advection-diffusion problems. The new method is similar to spectral element method for deterministic problems but with h-p discretization of the random space.

  8. Rainwater Harvesting: Landscape Methods 

    E-Print Network [OSTI]

    Lesikar, Bruce J.; Mechell, Justin; Alexander, Rachel

    2008-05-30T23:59:59.000Z

    landscape methods can save consumers money, reduce the demand for potable water, use water efficiently, and reduce flooding, erosion and surface water contamination....

  9. Method of degrading trinitrotoluene

    DOE Patents [OSTI]

    Tyndall, Richard L. (Clinton, TN); Vass, Arpad (Oak Ridge, TN)

    1996-01-01T23:59:59.000Z

    A method of eluting trinitrotoluene (TNT) from soil using a dispersant from bacterial intra-amoebic isolate 1s, ATCC 75229.

  10. Finite Volume Element Method

    E-Print Network [OSTI]

    2003-12-06T23:59:59.000Z

    FVE is closely related to the control volume finite element method ... simple stencils, to apply to a fairly wide range of fluid flow equations, to effectively treat.

  11. Method and apparatus for effecting light-off of a catalytic converter in a hybrid powertrain system

    DOE Patents [OSTI]

    Roos, Bryan Nathaniel; Spohn, Brian L

    2013-07-02T23:59:59.000Z

    A powertrain system includes a hybrid transmission and an internal combustion engine coupled to an exhaust aftertreatment device. A method for operating the powertrain system includes operating the hybrid transmission to generate tractive torque responsive to an operator torque request with the internal combustion engine in an engine-off state so long as the tractive torque is less than a threshold. The internal combustion engine is operated in an engine-on state at preferred operating conditions to effect light-off of the exhaust aftertreatment device and the hybrid transmission is coincidentally operated to generate tractive torque responsive to the operator torque request when the operator torque request exceeds the threshold. The internal combustion engine is then operated in the engine-on state to generate tractive torque responsive to the operator torque request.

  12. Systems and methods for commutating inductor current using a matrix converter

    DOE Patents [OSTI]

    Ransom, Ray M; Kajouke, Lateef A; Perisic, Milun

    2012-10-16T23:59:59.000Z

    Systems and methods are provided for delivering current using a matrix converter in a vehicle. An electrical system comprises an AC interface, a first conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the first conversion module, and a control module coupled to the first conversion module. The control module is configured to operate the first conversion module in a bidirectional operating mode to commutate current bidirectionally. When a magnitude of the current through the inductive element is greater than a first threshold value, the control module operates the conversion module in a unidirectional operating mode, wherein current is commutated unidirectionally.

  13. Reconstructing the nucleon-nucleon potential by a new coupled-channel inversion method

    E-Print Network [OSTI]

    Andrey Pupasov; Boris F. Samsonov; Jean-Marc Sparenberg; Daniel Baye

    2011-02-24T23:59:59.000Z

    A second-order supersymmetric transformation is presented, for the two-channel Schr\\"odinger equation with equal thresholds. It adds a Breit-Wigner term to the mixing parameter, without modifying the eigenphase shifts, and modifies the potential matrix analytically. The iteration of a few such transformations allows a precise fit of realistic mixing parameters in terms of a Pade expansion of both the scattering matrix and the effective-range function. The method is applied to build an exactly-solvable potential for the neutron-proton $^3S_1$-$^3D_1$ case.

  14. Study of {psi}(2S) decays to {gamma}pp, {pi}{sup 0}pp, and {eta}pp, and search for pp threshold enhancements

    SciTech Connect (OSTI)

    Alexander, J. P.; Cassel, D. G.; Das, S.; Ehrlich, R.; Fields, L.; Gibbons, L.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Kreinick, D. L.; Kuznetsov, V. E.; Patterson, J. R.; Peterson, D.; Riley, D.; Ryd, A.; Sadoff, A. J.; Shi, X.; Sun, W. M. [Cornell University, Ithaca, New York 14853 (United States); Yelton, J. [University of Florida, Gainesville, Florida 32611 (United States); Rubin, P. [George Mason University, Fairfax, Virginia 22030 (United States)

    2010-11-01T23:59:59.000Z

    The decays of {psi}(2S) into {gamma}pp, {pi}{sup 0}pp, and {eta}pp have been studied with the CLEO-c detector using a sample of 24.5x10{sup 6} {psi}(2S) events obtained from e{sup +}e{sup -} annihilations at {radical}(s)=3686 MeV. The data show evidence for the excitation of several N{sup *} resonances in p{pi}{sup 0} and p{eta} channels in {pi}{sup 0}pp and {eta}pp decays, and f{sub 2} states in {gamma}pp decay. Branching fractions for decays of {psi}(2S) to {gamma}pp, {pi}{sup 0}pp, and {eta}pp have been determined. No evidence for pp threshold enhancements was found in the reactions {psi}(2S){yields}Xpp, where X={gamma}, {pi}{sup 0}, {eta}. We do, however, find confirming evidence for a pp threshold enhancement in J/{psi}{yields}{gamma}pp as previously reported by BES.

  15. Measurement of cross sections of p(e,e'pi^+)n for near pion threshold and high-lying resonances at high Q^2

    SciTech Connect (OSTI)

    Kijun Park

    2012-04-01T23:59:59.000Z

    During the last decade, remarkable experimental data have been collected in an extensive programs to study the excitation of nucleon resonance (N*) at Jefferson Laboratory through pion electroproduction using polarized electron beam and unpolarized proton target. The CEBAF Large Acceptance Spectrometer (CLAS) is well suited for the study of a broad range of kinematics in the invariant mass W and photon virtuality Q{sup 2} with nearly complete angular coverage for the hadronic decays. Electron scattering allows us to probe the effective degrees of freedom in excited nucleon states from meson-baryon to dressed quarks in terms of varying the distance scale. The study of nucleon structure allows us to understand these effective degrees of freedom. In this proceeding, I present preliminary cross sections for single pion production in mass range of high-lying resonances as well as near the pion threshold. Analysis of N{pi}{sup +} cross sections together with N{pi}{sup 0} and N {pi}{pi} exclusive electroproduction data, will allow us for the first time to determine electrocouplings of several high-lying excited proton states (W {ge} 1.6 GeV) at photon virtualities that correspond to the transition toward the dominance of quark degrees of freedom. I also present preliminary result on the E{sub 0+} multipole near pion threshold at 2.0 GeV{sup 2} {le} Q{sup 2} {le} 4.5 GeV{sup 2} using exclusive N{pi}{sup +} electroproduction data.

  16. Method of forming nanodielectrics

    DOE Patents [OSTI]

    Tuncer, Enis [Knoxville, TN; Polyzos, Georgios [Oak Ridge, TN

    2014-01-07T23:59:59.000Z

    A method of making a nanoparticle filled dielectric material. The method includes mixing nanoparticle precursors with a polymer material and reacting the nanoparticle mixed with the polymer material to form nanoparticles dispersed within the polymer material to form a dielectric composite.

  17. Sampling system and method

    DOE Patents [OSTI]

    Decker, David L; Lyles, Brad F; Purcell, Richard G; Hershey, Ronald Lee

    2014-05-20T23:59:59.000Z

    An apparatus and method for supporting a tubing bundle during installation or removal. The apparatus includes a clamp for securing the tubing bundle to an external wireline. The method includes deploying the tubing bundle and wireline together, The tubing bundle is periodically secured to the wireline using a clamp.

  18. Water treatment method

    DOE Patents [OSTI]

    Martin, Frank S. (Farmersville, OH); Silver, Gary L. (Centerville, OH)

    1991-04-30T23:59:59.000Z

    A method for reducing the concentration of any undesirable metals dissolved in contaminated water, such as waste water. The method involves uniformly reacting the contaminated water with an excess amount of solid particulate calcium sulfite to insolubilize the undesirable metal ions, followed by removal thereof and of the unreacted calcium sulfite.

  19. Methods for data classification

    DOE Patents [OSTI]

    Garrity, George (Okemos, MI); Lilburn, Timothy G. (Front Royal, VA)

    2011-10-11T23:59:59.000Z

    The present invention provides methods for classifying data and uncovering and correcting annotation errors. In particular, the present invention provides a self-organizing, self-correcting algorithm for use in classifying data. Additionally, the present invention provides a method for classifying biological taxa.

  20. Water treatment method

    DOE Patents [OSTI]

    Martin, F.S.; Silver, G.L.

    1991-04-30T23:59:59.000Z

    A method is described for reducing the concentration of any undesirable metals dissolved in contaminated water, such as waste water. The method involves uniformly reacting the contaminated water with an excess amount of solid particulate calcium sulfite to insolubilize the undesirable metal ions, followed by removal thereof and of the unreacted calcium sulfite.

  1. Langlie Test Method Program for use with the HP-41CV/X calculator

    SciTech Connect (OSTI)

    Kopczewski, M.R.

    1987-10-01T23:59:59.000Z

    Explosive component designers need to test the sensitivity of some unit response as a function level of stress, for example, the sensitivity of a detonator or ignitor bridgewire to input current. There exists a threshold level, above which the detonator will function and below which it will not. Statistical testing of explosive components often requires destructive testing of expensive hardware. If the unit functions, it is destroyed; and if it doesn't fire, the results from any further testing cannot be relied on because the initial test affects the detonator. In order to obtain meaningful results and not expend a large number of units, the Langlie ''One-Shot'' Method of testing is employed. Typical component attributes that require Langlie testing include ''all-fire'' and ''no-fire'' tests to determine threshold levels of performance. Generally, any sensitivity testing lends itself to the Langlie method. This method has also been shown to be insensitive to design. Typically, support test groups and venders implement the test method with their own computers. The method is subject to some interpretation which may lead to inconsistency in results from facility to facility. Another concern is that an error made in choosing a stimulus level will affect subsequent levels, resulting in an analysis that is not a true Langlie. A program has been written for the HP-41CV/X calculator in order to standardize the Langlie test procedures at the various facilities, and to minimize the possibilities of introducing errors in the test method. A distinct advantage of using the calculator is the ability to hand carry it in the field and perform the Langlie test method at remote locations. 2 refs.

  2. RESEARCH ARTICLE An Alternating Direction Method for Total ...

    E-Print Network [OSTI]

    2014-08-13T23:59:59.000Z

    where the soft-thresholding operator T is defined componentwise as. T (x, ?)i ... left-hand-side of the above system is positive definite and tridiagonal. Hence ...

  3. Method for inducing hypothermia

    DOE Patents [OSTI]

    Becker, Lance B.; Hoek, Terry Vanden; Kasza, Kenneth E.

    2005-11-08T23:59:59.000Z

    Systems for phase-change particulate slurry cooling equipment and methods to induce hypothermia in a patient through internal and external cooling are provided. Subcutaneous, intravascular, intraperitoneal, gastrointestinal, and lung methods of cooling are carried out using saline ice slurries or other phase-change slurries compatible with human tissue. Perfluorocarbon slurries or other slurry types compatible with human tissue are used for pulmonary cooling. And traditional external cooling methods are improved by utilizing phase-change slurry materials in cooling caps and torso blankets.

  4. Method for inducing hypothermia

    DOE Patents [OSTI]

    Becker, Lance B. (Chicago, IL); Hoek, Terry Vanden (Chicago, IL); Kasza, Kenneth E. (Palos Park, IL)

    2003-04-15T23:59:59.000Z

    Systems for phase-change particulate slurry cooling equipment and methods to induce hypothermia in a patient through internal and external cooling are provided. Subcutaneous, intravascular, intraperitoneal, gastrointestinal, and lung methods of cooling are carried out using saline ice slurries or other phase-change slurries compatible with human tissue. Perfluorocarbon slurries or other slurry types compatible with human tissue are used for pulmonary cooling. And traditional external cooling methods are improved by utilizing phase-change slurry materials in cooling caps and torso blankets.

  5. Method for inducing hypothermia

    DOE Patents [OSTI]

    Becker, Lance B. (Chicago, IL); Hoek, Terry Vanden (Chicago, IL); Kasza, Kenneth E. (Palos Park, IL)

    2008-09-09T23:59:59.000Z

    Systems for phase-change particulate slurry cooling equipment and methods to induce hypothermia in a patient through internal and external cooling are provided. Subcutaneous, intravascular, intraperitoneal, gastrointestinal, and lung methods of cooling are carried out using saline ice slurries or other phase-change slurries compatible with human tissue. Perfluorocarbon slurries or other slurry types compatible with human tissue are used for pulmonary cooling. And traditional external cooling methods are improved by utilizing phase-change slurry materials in cooling caps and torso blankets.

  6. Catalytic reforming methods

    DOE Patents [OSTI]

    Tadd, Andrew R; Schwank, Johannes

    2013-05-14T23:59:59.000Z

    A catalytic reforming method is disclosed herein. The method includes sequentially supplying a plurality of feedstocks of variable compositions to a reformer. The method further includes adding a respective predetermined co-reactant to each of the plurality of feedstocks to obtain a substantially constant output from the reformer for the plurality of feedstocks. The respective predetermined co-reactant is based on a C/H/O atomic composition for a respective one of the plurality of feedstocks and a predetermined C/H/O atomic composition for the substantially constant output.

  7. A regularized simplex method

    E-Print Network [OSTI]

    2013-02-25T23:59:59.000Z

    Abstract. In case of a special problem class, the simplex method can be implemented as a ... of the dual problem, in case a special simplex pricing rule is used.

  8. Bayesian methods in bioinformatics

    E-Print Network [OSTI]

    Baladandayuthapani, Veerabhadran

    2007-04-25T23:59:59.000Z

    - niques for drawing random samples from the posterior for inference. We show that the approach achieves very competitive performance as compared to other methods. The second part focuses on modeling DNA microarray data. Microarray technology enables us...

  9. Stochastic Methods Gabriel Zachmann

    E-Print Network [OSTI]

    Behnke, Sven

    1 Stochastic Methods Gabriel Zachmann Universität Bonn Motivation ADB-Trees Stochastic Closest-Trees [Klein & Zachmann, 2003] 2. Stochastic Closest Features Tracking [Raghupathi et al., 2004; Debunne & Guy

  10. Method for characterization of repetitive frequency laser resistance of optical coatings

    SciTech Connect (OSTI)

    Zhang Dong; He Hongbo; Zhao Yuanan; Li Dawei; Fan Zhengxiu

    2009-05-20T23:59:59.000Z

    The characterization of repetitive frequency (S-on-1) laser resistance of optical coatings was investigated experimentally based on damage pattern divided into slight damage and severe damage. It was discovered that, when only the slight damage pattern was counted, a peak would be seen in the damage probability curve, and the laser fluence at this peak was stable as pulse sequence S changed. The stable laser fluence at this peak, therefore, could be employed to characterize the repetitive frequency laser resistance of optical coatings. This method is different from the method proposed by the International Organization for Standardization [ISO 11254-2(2001)] and has the advantage of simplicity in practical applications. According to our analysis, it is a method that can obtain the functional damage threshold of optics.

  11. Method of treating depression

    DOE Patents [OSTI]

    Henn, Fritz

    2013-04-09T23:59:59.000Z

    Methods for treatment of depression-related mood disorders in mammals, particularly humans are disclosed. The methods of the invention include administration of compounds capable of enhancing glutamate transporter activity in the brain of mammals suffering from depression. ATP-sensitive K.sup.+ channel openers and .beta.-lactam antibiotics are used to enhance glutamate transport and to treat depression-related mood disorders and depressive symptoms.

  12. Method of treating depression

    DOE Patents [OSTI]

    Henn, Fritz (East Patchogue, NY)

    2012-01-24T23:59:59.000Z

    Methods for treatment of depression-related mood disorders in mammals, particularly humans are disclosed. The methods of the invention include administration of compounds capable of enhancing glutamate transporter activity in the brain of mammals suffering from depression. ATP-sensitive K.sup.+ channel openers and .beta.-lactam antibiotics are used to enhance glutamate transport and to treat depression-related mood disorders and depressive symptoms.

  13. Pushing schedule derivation method

    SciTech Connect (OSTI)

    Henriquez, B. [Compania Siderurgica Huachipato S.A., Talcahuano (Chile)

    1996-12-31T23:59:59.000Z

    The development of a Pushing Schedule Derivation Method has allowed the company to sustain the maximum production rate at CSH`s Coke Oven Battery, in spite of having single set oven machinery with a high failure index as well as a heat top tendency. The stated method provides for scheduled downtime of up to two hours for machinery maintenance purposes, periods of empty ovens for decarbonization and production loss recovery capability, while observing lower limits and uniformity of coking time.

  14. Relativistic R-matrix close-coupling method based on the effective Hamiltonian in many-body perturbation theory

    SciTech Connect (OSTI)

    Vilkas, Marius J.; Ishikawa, Yasuyuki [Department of Chemistry, University of Puerto Rico, P.O. Box 23346 San Juan, Puerto Rico 00931-3346 (United States)

    2007-06-15T23:59:59.000Z

    A relativistic R-matrix close-coupling method is developed and implemented based on effective many-body Hamiltonians for accurate representation of the target and collisional states in multielectron ions. The effective Hamiltonian in relativistic multireference many-body perturbation theory accurately accounts for short-range many-body interactions unaccounted for in the extant nonrelativistic and Breit-Pauli R-matrix methods. The method is successfully applied to the near-threshold electron impact excitation of the 3s{sup 2} {sup 1}S{yields}3s3p {sup 3}P transition in Mg-like argon (Ar{sup 6+}) ion where the observed disagreement between the experimental absolute total cross sections and those predicted by using the Breit-Pauli R-matrix method reveals an inadequacy of the R-matrix methods based on the configuration-interaction representation of the basis states.

  15. Sub-250?nm low-threshold deep-ultraviolet AlGaN-based heterostructure laser employing HfO{sub 2}/SiO{sub 2} dielectric mirrors

    SciTech Connect (OSTI)

    Kao, Tsung-Ting; Liu, Yuh-Shiuan; Mahbub Satter, Md.; Li, Xiao-Hang; Lochner, Zachary; Douglas Yoder, P.; Detchprohm, Theeradetch; Dupuis, Russell D.; Shen, Shyh-Chiang, E-mail: shyh.shen@ece.gatech.edu; Ryou, Jae-Hyun [School of Electrical and Computer Engineering, Georgia Institute of Technology, 777 Atlantic Dr. NW, Atlanta, Georgia 30332-0250 (United States)] [School of Electrical and Computer Engineering, Georgia Institute of Technology, 777 Atlantic Dr. NW, Atlanta, Georgia 30332-0250 (United States); Fischer, Alec M.; Wei, Yong; Xie, Hongen; Ponce, Fernando A. [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States)] [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States)

    2013-11-18T23:59:59.000Z

    We report a sub-250-nm, optically pumped, deep-ultraviolet laser using an Al{sub x}Ga{sub 1?x}N-based multi-quantum-well structure grown on a bulk Al-polar c-plane AlN substrate. TE-polarization-dominant lasing action was observed at room temperature with a threshold pumping power density of 250?kW/cm{sup 2}. After employing high-reflectivity SiO{sub 2}/HfO{sub 2} dielectric mirrors on both facets, the threshold pumping power density was further reduced to 180?kW/cm{sup 2}. The internal loss and threshold modal gain can be calculated as 2?cm{sup ?1} and 10.9?cm{sup ?1}, respectively.

  16. Scintillation efficiency measurement of Na recoils in NaI(Tl) below the DAMA/LIBRA energy threshold

    E-Print Network [OSTI]

    Xu, Jingke; Calaprice, Frank; Westerdale, Shawn; Froborg, Francis; Suerfu, Burkhant; Alexander, Thomas; Aprahamian, Ani; Back, Henning O; Casarella, Clark; Fang, Xiao; Gupta, Yogesh K; Ianni, Aldo; Lamere, Edward; Lippincott, W Hugh; Liu, Qian; Lyons, Stephanie; Siegl, Kevin; Smith, Mallory; Tan, Wanpeng; Kolk, Bryant Vande

    2015-01-01T23:59:59.000Z

    The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3keV$_{\\text{nr}}$ to 52keV$_{\\text{nr}}$, covering the whole DAMA/LIBRA energy region for light WIMP interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies, but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

  17. High-order perturbation expansion of non-Hermitian Floquet theory for multiphoton and above-threshold ionization processes

    E-Print Network [OSTI]

    Telnov, Dmitry A.; Chu, Shih-I

    1999-12-14T23:59:59.000Z

    within the interval @ 0,N 21 # . Equation ~34! is valid in general except for the m 50, l5l0 case. In this special case the sum does not include i5 j0: @ G # j l00,j8l005 (i50 iÞ j0 N21 @ f i ,l0 (0) # j@f i ,l0 (0) # j 8 Ei ,l02«0 (0) . ~35! As one can... Floquet matrix. The motivations of this paper are two- fold. First, we outline a procedure that works for both weak and intermediate laser intensities but does not require the diagonalization of the full Floquet matrix. Second, the method will not only...

  18. Evidence for a Narrow Near-Threshold Structure in the $J/\\psi\\phi$ Mass Spectrum in $B^+\\to J/\\psi\\phi K^+$ Decays

    SciTech Connect (OSTI)

    Aaltonen, T.; /Helsinki Inst. of Phys.; Adelman, Jahred A.; /Chicago U., EFI; Akimoto, T.; /Tsukuba U.; Alvarez Gonzalez, B.; /Cantabria Inst. of Phys.; Amerio, S.; /INFN, Padua; Amidei, Dante E.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, Alberto; /Frascati; Antos, Jaroslav; /Comenius U.; Apollinari, G.; /Fermilab; Apresyan, A.; /Purdue U. /Waseda U.

    2009-03-01T23:59:59.000Z

    Evidence is reported for a narrow structure near the J/{psi}{phi} threshold in exclusive B{sup +} {yields} J/{psi}{phi}K{sup +} decays produced in {bar p}p collisions at {radical}s = 1.96 TeV. A signal of 14 {+-} 5 events, with statistical significance in excess of 3.8 standard deviations, is observed in a data sample corresponding to an integrated luminosity of 2.7 fb{sup -1}, collected by the CDF II detector. The mass and natural width of the structure are measured to be 4143.0 {+-} 2.9(stat) {+-} 1.2(syst) MeV/c{sup 2} and 11.7{sub -5.0}{sup +8.3}(stat) {+-} 3.7(syst) MeV/c{sup 2}.

  19. Fabrication of silica aerogel with $n$ = 1.08 for $e^+/?^+$ separation in a threshold Cherenkov counter of the J-PARC TREK/E36 experiment

    E-Print Network [OSTI]

    Makoto Tabata; Akihisa Toyoda; Hideyuki Kawai; Youichi Igarashi; Jun Imazato; Suguru Shimizu; Hirohito Yamazaki

    2015-06-09T23:59:59.000Z

    This study presents the development of hydrophobic silica aerogel for use as a radiator in threshold-type Cherenkov counters. These counters are to be used for separating positrons and positive muons produced by kaon decay in the J-PARC TREK/E36 experiment. We chose to employ aerogel with a refractive index of 1.08 to identify charged particles with momenta of approximately 240 MeV/$c$, and the radiator block shape was designed with a trapezoidal cross-section to fit the barrel region surrounding the kaon stopping target in the center of the TREK/E36 detector system. Including spares, we obtained 30 crack-free aerogel blocks segmented into two layers, each layer having a thickness of 2 cm and a length of 18 cm, to fill 12 counter modules. Optical measurements showed that the produced aerogel tiles had the required refractive indices and transparency.

  20. Calibration of a solid state nuclear track detector (SSNTD) with high detection threshold to search for rare events in cosmic rays

    E-Print Network [OSTI]

    S. Dey; D. Gupta; A. Maulik; Sibaji Raha; Swapan K. Saha; D. Syam; J. Pakarinen; D. Voulot; F. Wenander

    2011-03-23T23:59:59.000Z

    We have investigated a commercially available polymer for its suitability as a solid state nuclear track detector (SSNTD). We identified that polymer to be polyethylene terephthalate (PET) and found that it has a higher detection threshold compared to many other widely used SSNTDs which makes this detector particularly suitable for rare event search in cosmic rays as it eliminates the dominant low Z background. Systematic studies were carried out to determine its charge response which is essential before any new material can be used as an SSNTD. In this paper we describe the charge response of PET to 129Xe, 78Kr and 49Ti ions from the REX-ISOLDE facility at CERN, present the calibration curve for PET and characterize it as a nuclear track detector.

  1. Thresholds and criteria for evaluating and communicating impact significance in environmental statements: 'See no evil, hear no evil, speak no evil'?

    SciTech Connect (OSTI)

    Wood, Graham [Department of Planning, School of the Built Environment, Oxford Brookes University, Gipsy Lane, Oxford, 0X3 0BP (United Kingdom)], E-mail: gjwood@brookes.ac.uk

    2008-01-15T23:59:59.000Z

    The evaluation and communication of the significance of environmental effects remains a critical yet poorly understood component of EIA theory and practice. Following a conceptual overview of the generic dimensions of impact significance in EIA, this paper reports upon the findings of an empirical study of recent environmental impact statements that considers the treatment of significance for impacts concerning landscape ('see no evil') and noise ('hear no evil'), focussing specifically upon the evaluation and communication of impact significance ('speak no evil') in UK practice. Particular attention is given to the use of significance criteria and thresholds, including the development of a typology of approaches applied within the context of noise and landscape/visual impacts. Following a broader discussion of issues surrounding the formulation, application and interpretation of significance criteria, conclusions and recommendations relevant to wider EIA practice are suggested.

  2. Limits on Low-Mass WIMP Dark Matter with an Ultra-Low-Energy Germanium Detector at 220 eV Threshold

    E-Print Network [OSTI]

    Shin-Ted Lin; H. T. Wong; for the TEXONO Collaboration

    2008-10-20T23:59:59.000Z

    An energy threshold of (220$\\pm$10) eV was achieved at an efficiency of 50% with a four-channel ultra-low-energy germanium detector each with an active mass of 5 g\\cite{wimppaper}. This provides a unique probe to WIMP dark matter with mass below 10 GeV. With low background data taken at the Kuo-Sheng Laboratory, constraints on WIMPs in the galactic halo were derived. Both spin-independent WIMP-nucleon and spin-dependent WIMP-neutron bounds improve over previous results for WIMP mass between 3$-$6 GeV. These results, together with those on spin-dependent couplings, will be presented. Sensitivities for full-scale experiments were projected. This detector technique makes the unexplored sub-keV energy window accessible for new neutrino and dark matter experiments.

  3. Optical breakdown threshold in nanosecond high repetition second harmonic generation by periodically poled Mg-doped LiTaO{sub 3} crystal

    SciTech Connect (OSTI)

    Louchev, Oleg A.; Wada, Satoshi [Center for Advanced Photonics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Center for Advanced Photonics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hatano, Hideki; Kitamura, Kenji [Division of Environment and Energy Materials, National Institute for Materials Science (NIMS) 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)] [Division of Environment and Energy Materials, National Institute for Materials Science (NIMS) 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2013-08-26T23:59:59.000Z

    Our study shows that a local temperature increase of ?1 K in the crystal lattice caused by second harmonic generation (SHG) and two-photon absorption of 532 nm radiation at the rear of periodically poled stoichiometric LiTaO{sub 3} crystal by changing spontaneous polarization induces a pyroelectric field ?10 kV/cm, accelerating free electrons to an energy of ?10 eV, followed by optical breakdown and crystal damage. Theoretical analysis leads to an explicit expression for the threshold laser fluence of optical breakdown giving ?1.2 J/cm{sup 2} for 1064 nm input radiation in 6.8 kHz pulsed SHG operation, agreeing well with the experimentally found value ?1.32 J/cm{sup 2}.

  4. AN “EASY” PARALLEL SIMPLEX METHOD

    E-Print Network [OSTI]

    Richard Van Slyke

    2006-07-10T23:59:59.000Z

    Both revised simplex and interior point methods have difficulty with dense ... Keywords: Wavelet decomposition, linear programming; Standard simplex method; ...

  5. Methods of forming steel

    DOE Patents [OSTI]

    Branagan, Daniel J. (Iona, ID); Burch, Joseph V. (Shelley, ID)

    2001-01-01T23:59:59.000Z

    In one aspect, the invention encompasses a method of forming a steel. A metallic glass is formed and at least a portion of the glass is converted to a crystalline steel material having a nanocrystalline scale grain size. In another aspect, the invention encompasses another method of forming a steel. A molten alloy is formed and cooled the alloy at a rate which forms a metallic glass. The metallic glass is devitrified to convert the glass to a crystalline steel material having a nanocrystalline scale grain size. In yet another aspect, the invention encompasses another method of forming a steel. A first metallic glass steel substrate is provided, and a molten alloy is formed over the first metallic glass steel substrate to heat and devitrify at least some of the underlying metallic glass of the substrate.

  6. Actinide extraction methods

    DOE Patents [OSTI]

    Peterman, Dean R. (Idaho Falls, ID) [Idaho Falls, ID; Klaehn, John R. (Idaho Falls, ID) [Idaho Falls, ID; Harrup, Mason K. (Idaho Falls, ID) [Idaho Falls, ID; Tillotson, Richard D. (Moore, ID) [Moore, ID; Law, Jack D. (Pocatello, ID) [Pocatello, ID

    2010-09-21T23:59:59.000Z

    Methods of separating actinides from lanthanides are disclosed. A regio-specific/stereo-specific dithiophosphinic acid having organic moieties is provided in an organic solvent that is then contacted with an acidic medium containing an actinide and a lanthanide. The method can extend to separating actinides from one another. Actinides are extracted as a complex with the dithiophosphinic acid. Separation compositions include an aqueous phase, an organic phase, dithiophosphinic acid, and at least one actinide. The compositions may include additional actinides and/or lanthanides. A method of producing a dithiophosphinic acid comprising at least two organic moieties selected from aromatics and alkyls, each moiety having at least one functional group is also disclosed. A source of sulfur is reacted with a halophosphine. An ammonium salt of the dithiophosphinic acid product is precipitated out of the reaction mixture. The precipitated salt is dissolved in ether. The ether is removed to yield the dithiophosphinic acid.

  7. Method of grid generation

    DOE Patents [OSTI]

    Barnette, Daniel W. (Veguita, NM)

    2002-01-01T23:59:59.000Z

    The present invention provides a method of grid generation that uses the geometry of the problem space and the governing relations to generate a grid. The method can generate a grid with minimized discretization errors, and with minimal user interaction. The method of the present invention comprises assigning grid cell locations so that, when the governing relations are discretized using the grid, at least some of the discretization errors are substantially zero. Conventional grid generation is driven by the problem space geometry; grid generation according to the present invention is driven by problem space geometry and by governing relations. The present invention accordingly can provide two significant benefits: more efficient and accurate modeling since discretization errors are minimized, and reduced cost grid generation since less human interaction is required.

  8. Method for determining molten metal pool level in twin-belt continuous casting machines

    DOE Patents [OSTI]

    Kaiser, Timothy D. (Colchester, VT); Daniel, Sabah S. (Pittsburgh, PA); Dykes, Charles D. (Milton, VT)

    1989-03-21T23:59:59.000Z

    A method for determining level of molten metal in the input of a continuous metal casting machine having at least one endless, flexible, revolving casting belt with a surface which engages the molten metal to be cast and a reverse, cooled surface along which is directed high velocity liquid coolant includes the steps of predetermining the desired range of positions of the molten metal pool and positioning at least seven heat-sensing transducers in bearing contact with the moving reverse belt surface and spaced in upstream-downstream relationship relative to belt travel spanning the desired pool levels. A predetermined temperature threshold is set, somewhat above coolant temperature and the output signals of the transducer sensors are scanned regarding their output signals indicative of temperatures of the moving reverse belt surface. Position of the molten pool is determined using temperature interpolation between any successive pair of upstream-downstream spaced sensors, which follows confirmation that two succeeding downstream sensors are at temperature levels exceeding threshold temperature. The method accordingly provides high resolution for determining pool position, and verifies the determined position by utilizing full-strength signals from two succeeding downstream sensors. In addition, dual sensors are used at each position spanning the desired range of molten metal pool levels to provide redundancy, wherein only the higher temperature of each pair of sensors at a station is utilized.

  9. Unorthodox theoretical methods

    SciTech Connect (OSTI)

    Nedd, Sean

    2012-06-20T23:59:59.000Z

    The use of the ReaxFF force field to correlate with NMR mobilities of amine catalytic substituents on a mesoporous silica nanosphere surface is considered. The interfacing of the ReaxFF force field within the Surface Integrated Molecular Orbital/Molecular Mechanics (SIMOMM) method, in order to replicate earlier SIMOMM published data and to compare with the ReaxFF data, is discussed. The development of a new correlation consistent Composite Approach (ccCA) is presented, which incorporates the completely renormalized coupled cluster method with singles, doubles and non-iterative triples corrections towards the determination of heats of formations and reaction pathways which contain biradical species.

  10. Methods of visualizing graphs

    DOE Patents [OSTI]

    Wong, Pak C. (Richland, WA); Mackey, Patrick S. (Kennewick, WA); Perrine, Kenneth A. (Richland, WA); Foote, Harlan P. (Richland, WA); Thomas, James J. (Richland, WA)

    2008-12-23T23:59:59.000Z

    Methods for visualizing a graph by automatically drawing elements of the graph as labels are disclosed. In one embodiment, the method comprises receiving node information and edge information from an input device and/or communication interface, constructing a graph layout based at least in part on that information, wherein the edges are automatically drawn as labels, and displaying the graph on a display device according to the graph layout. In some embodiments, the nodes are automatically drawn as labels instead of, or in addition to, the label-edges.

  11. Contaminant treatment method

    DOE Patents [OSTI]

    Shapiro, Andrew Philip (Schenectady, NY); Thornton, Roy Fred (Schenectady, NY); Salvo, Joseph James (Schenectady, NY)

    2003-01-01T23:59:59.000Z

    The present invention provides a method for treating contaminated media. The method comprises introducing remediating ions consisting essentially of ferrous ions, and being peroxide-free, in the contaminated media; applying a potential difference across the contaminated media to cause the remediating ions to migrate into contact with contaminants in the contaminated media; chemically degrading contaminants in the contaminated media by contact with the remediating ions; monitoring the contaminated media for degradation products of the contaminants; and controlling the step of applying the potential difference across the contaminated media in response to the step of monitoring.

  12. Biomass treatment method

    DOE Patents [OSTI]

    Friend, Julie (Claymont, DE); Elander, Richard T. (Evergreen, CO); Tucker, III; Melvin P. (Lakewood, CO); Lyons, Robert C. (Arvada, CO)

    2010-10-26T23:59:59.000Z

    A method for treating biomass was developed that uses an apparatus which moves a biomass and dilute aqueous ammonia mixture through reaction chambers without compaction. The apparatus moves the biomass using a non-compressing piston. The resulting treated biomass is saccharified to produce fermentable sugars.

  13. LAB #8 Numerical Methods

    E-Print Network [OSTI]

    2005-10-20T23:59:59.000Z

    Page 1. LAB #8. Numerical Methods. Goal: The purpose of this lab is to explain how computers numerically ... Also you will examine what .... (7) Now consider the differential equation ... 3-exp(2*y)+sqrt(t)/y; (Don't forget the “;” at the end.).

  14. Sampling system and method

    DOE Patents [OSTI]

    Decker, David L.; Lyles, Brad F.; Purcell, Richard G.; Hershey, Ronald Lee

    2013-04-16T23:59:59.000Z

    The present disclosure provides an apparatus and method for coupling conduit segments together. A first pump obtains a sample and transmits it through a first conduit to a reservoir accessible by a second pump. The second pump further conducts the sample from the reservoir through a second conduit.

  15. Heart imaging method

    DOE Patents [OSTI]

    Collins, H. Dale (Richland, WA); Gribble, R. Parks (Richland, WA); Busse, Lawrence J. (Littleton, CO)

    1991-01-01T23:59:59.000Z

    A method for providing an image of the human heart's electrical system derives time-of-flight data from an array of EKG electrodes and this data is transformed into phase information. The phase information, treated as a hologram, is reconstructed to provide an image in one or two dimensions of the electrical system of the functioning heart.

  16. Method of purifying isosaccharinate

    DOE Patents [OSTI]

    Rai, Dhanpat (Yachats, OR); Moore, Robert C. (Edgewood, NM); Tucker, Mark D. (Albuquerque, NM)

    2010-09-07T23:59:59.000Z

    A method of purifying isosaccharinate by mixing sodium carbonate, potassium carbonate, sodium hydroxide or potassium hydroxide with calcium isosaccharinate, removing the precipitated calcium carbonate and adjusting the pH to between approximately 4.5 to 5.0 thereby removing excess carbonate and hydroxide to provide an acidic solution containing isosaccharinate.

  17. Method of dehydrocyclizing alkanes

    SciTech Connect (OSTI)

    Buss, W.C.; Hughes, T.R.

    1986-12-23T23:59:59.000Z

    A method is described of reforming hydrocarbons comprising contacting the hydrocarbons with a catalyst comprising a large-pore zeolite containing: (a) at least one Group VIII metal; and (b) an alkaline earth metal selected from the group consisting of barium, strontium and calcium. The Selectivity Index of the catalyst is greater than 60%.

  18. Cooling load estimation methods

    SciTech Connect (OSTI)

    McFarland, R.D.

    1984-01-01T23:59:59.000Z

    Ongoing research on quantifying the cooling loads in residential buildings, particularly buildings with passive solar heating systems, is described. Correlations are described that permit auxiliary cooling estimates from monthly average insolation and weather data. The objective of the research is to develop a simple analysis method, useful early in design, to estimate the annual cooling energy required of a given building.

  19. Yet another fast multipole method without multipoles ---Pseudoparticle multipole method

    E-Print Network [OSTI]

    Makino, Jun

    Yet another fast multipole method without multipoles --- Pseudo­particle multipole method Junichiro In this paper we describe a new approach to implement the O(N) fast multipole method and O(N log N) tree method. As in the case of the fast multipole method (FMM) [6], it is possible to implement higher order multipole

  20. Study of digital pulse shape discrimination method for n-{\\gamma} separation of EJ-301 liquid scintillation detector

    E-Print Network [OSTI]

    Wan, Bo; Chen, Liang; Ge, Honglin; Ma, Fei; Zhang, Hongbin; Ju, Yongqin; Zhang, Yanbin; Li, Yanyan; Xu, Xiaowei

    2015-01-01T23:59:59.000Z

    A digital pulse shape discrimination system based on a programmable module NI-5772 has been established and tested with EJ-301 liquid scintillation detector. The module was operated by means of running programs developed in LabVIEW with the sampling frequency up to 1.6GS/s. Standard gamma sources 22Na, 137Cs and 60Co were used to calibrate the EJ-301 liquid scintillation detector, and the gamma response function has been obtained. Digital algorithms for charge comparison method and zero-crossing method have been developed. The experimental results showed that both digital signal processing (DSP) algorithms could discriminate neutrons from gamma-rays. Moreover, the zero-crossing method shows better n-{\\gamma} discrimination at 80 keVee and lower, whereas the charge comparison method gives better results at higher thresholds. In addition, the figure-of-merit (FOM) of two different dimension detectors were extracted at 9 energy thresholds, and it was found that the smaller one presented a better n-{\\gamma} separ...

  1. Simulating biofilm deformation and detachment with the immersed boundary method

    E-Print Network [OSTI]

    Sudarsan, Rangarajan; Stockie, John M; Eberl, Hermann J

    2015-01-01T23:59:59.000Z

    We apply the immersed boundary (or IB) method to simulate deformation and detachment of a periodic array of wall-bounded biofilm colonies in response to a linear shear flow. The biofilm material is represented as a network of Hookean springs that are placed along the edges of a triangulation of the biofilm region. The interfacial shear stress, lift and drag forces acting on the biofilm colony are computed by using fluid stress jump method developed by Williams, Fauci and Gaver [Disc. Contin. Dyn. Sys. B 11(2):519-540, 2009], with a modified version of their exclusion filter. Our detachment criterion is based on the novel concept of an averaged equivalent continuum stress tensor defined at each IB point in the biofilm which is then used to determine a corresponding von Mises yield stress; wherever this yield stress exceeds a given critical threshold the connections to that node are severed, thereby signalling the onset of a detachment event. In order to capture the deformation and detachment behaviour of a bio...

  2. Ion sensing method

    DOE Patents [OSTI]

    Smith, Richard Harding; Martin, Glenn Brian

    2004-05-18T23:59:59.000Z

    The present invention allows the determination of trace levels of ionic substances in a sample solution (ions, metal ions, and other electrically charged molecules) by coupling a separation method, such as liquid chromatography, with ion selective electrodes (ISE) prepared so as to allow detection at activities below 10.sup.-6 M. The separation method distributes constituent molecules into fractions due to unique chemical and physical properties, such as charge, hydrophobicity, specific binding interactions, or movement in an electrical field. The separated fractions are detected by means of the ISE(s). These ISEs can be used singly or in an array. Accordingly, modifications in the ISEs are used to permit detection of low activities, specifically, below 10.sup.-6 M, by using low activities of the primary analyte (the molecular species which is specifically detected) in the inner filling solution of the ISE. Arrays constructed in various ways allow flow-through sensing for multiple ions.

  3. Inspection system calibration methods

    DOE Patents [OSTI]

    Deason, Vance A.; Telschow, Kenneth L.

    2004-12-28T23:59:59.000Z

    An inspection system calibration method includes producing two sideband signals of a first wavefront; interfering the two sideband signals in a photorefractive material, producing an output signal therefrom having a frequency and a magnitude; and producing a phase modulated operational signal having a frequency different from the output signal frequency, a magnitude, and a phase modulation amplitude. The method includes determining a ratio of the operational signal magnitude to the output signal magnitude, determining a ratio of a 1st order Bessel function of the operational signal phase modulation amplitude to a 0th order Bessel function of the operational signal phase modulation amplitude, and comparing the magnitude ratio to the Bessel function ratio.

  4. Biological tracer method

    DOE Patents [OSTI]

    Strong-Gunderson, J.M.; Palumbo, A.V.

    1998-09-15T23:59:59.000Z

    The present invention is a biological tracer method for characterizing the movement of a material through a medium, comprising the steps of: introducing a biological tracer comprising a microorganism having ice nucleating activity into a medium; collecting at least one sample of the medium from a point removed from the introduction point; and analyzing the sample for the presence of the biological tracer. The present invention is also a method for using a biological tracer as a label for material identification by introducing a biological tracer having ice nucleating activity into a material, collecting a sample of a portion of the labelled material and analyzing the sample for the presence of the biological tracer. 2 figs.

  5. Biological tracer method

    DOE Patents [OSTI]

    Strong-Gunderson, Janet M. (Ten Mile, TN); Palumbo, Anthony V. (Oak Ridge, TN)

    1998-01-01T23:59:59.000Z

    The present invention is a biological tracer method for characterizing the movement of a material through a medium, comprising the steps of: introducing a biological tracer comprising a microorganism having ice nucleating activity into a medium; collecting at least one sample of the medium from a point removed from the introduction point; and analyzing the sample for the presence of the biological tracer. The present invention is also a method for using a biological tracer as a label for material identification by introducing a biological tracer having ice nucleating activity into a material, collecting a sample of a portion of the labelled material and analyzing the sample for the presence of the biological tracer.

  6. Cold isopressing method

    DOE Patents [OSTI]

    Chen, Jack C. (Getzville, NY); Stawisuck, Valerie M. (North Tonawanda, NY); Prasad, Ravi (East Amherst, NY)

    2003-01-01T23:59:59.000Z

    A cold isopressing method in which two or more layers of material are formed within an isopressing mold. One of the layers consists of a tape-cast film. The layers are isopressed within the isopressing mold, thereby to laminate the layers and to compact the tape-cast film. The isopressing mold can be of cylindrical configuration with the layers being coaxial cylindrical layers. The materials used in forming the layers can contain green ceramic materials and the resultant structure can be fired and sintered as necessary and in accordance with known methods to produce a finished composite, ceramic structure. Further, such green ceramic materials can be of the type that are capable of conducting hydrogen or oxygen ions at high temperature with the object of utilizing the finished composite ceramic structure as a ceramic membrane element.

  7. Die singulation method

    DOE Patents [OSTI]

    Swiler, Thomas P [Albuquerque, NM; Garcia, Ernest J [Albuquerque, NM; Francis, Kathryn M [Rio Rancho, NM

    2014-01-07T23:59:59.000Z

    A method is disclosed for singulating die from a semiconductor substrate (e.g. a semiconductor-on-insulator substrate or a bulk silicon substrate) containing an oxide layer (e.g. silicon dioxide or a silicate glass) and one or more semiconductor layers (e.g. monocrystalline or polycrystalline silicon) located above the oxide layer. The method etches trenches through the substrate and through each semiconductor layer about the die being singulated, with the trenches being offset from each other around at least a part of the die so that the oxide layer between the trenches holds the substrate and die together. The trenches can be anisotropically etched using a Deep Reactive Ion Etching (DRIE) process. After the trenches are etched, the oxide layer between the trenches can be etched away with a HF etchant to singulate the die. A release fixture can be located near one side of the substrate to receive the singulated die.

  8. Die singulation method

    DOE Patents [OSTI]

    Swiler, Thomas P.; Garcia, Ernest J.; Francis, Kathryn M.

    2013-06-11T23:59:59.000Z

    A method is disclosed for singulating die from a semiconductor substrate (e.g. a semiconductor-on-insulator substrate or a bulk silicon substrate) containing an oxide layer (e.g. silicon dioxide or a silicate glass) and one or more semiconductor layers (e.g. monocrystalline or polycrystalline silicon) located above the oxide layer. The method etches trenches through the substrate and through each semiconductor layer about the die being singulated, with the trenches being offset from each other around at least a part of the die so that the oxide layer between the trenches holds the substrate and die together. The trenches can be anisotropically etched using a Deep Reactive Ion Etching (DRIE) process. After the trenches are etched, the oxide layer between the trenches can be etched away with an HF etchant to singulate the die. A release fixture can be located near one side of the substrate to receive the singulated die.

  9. KALRA AND LYSECKY: ASHOUEI et al.: CARLONI et al.: LIU et al.: AN APPROACH FOR ADAPTIVE DRAM TEMPERATURE AND POWER MANAGEMENT 679 [8] P. Pant, R. K. Roy, and A. Chatterjee, "Dual-threshold voltage assign-

    E-Print Network [OSTI]

    Carloni, Luca

    TEMPERATURE AND POWER MANAGEMENT 679 [8] P. Pant, R. K. Roy, and A. Chatterjee, "Dual-threshold voltage assign, and K. Roy, "Novel sizing algorithm for yield improvement under process variation in nanometer. Narendra, S. Borkar, C. Hawkins, K. Roy, and V. De, "Technology scaling of optimum reverse body bias

  10. Chromosome doubling method

    DOE Patents [OSTI]

    Kato, Akio

    2006-11-14T23:59:59.000Z

    The invention provides methods for chromosome doubling in plants. The technique overcomes the low yields of doubled progeny associated with the use of prior techniques for doubling chromosomes in plants such as grasses. The technique can be used in large scale applications and has been demonstrated to be highly effective in maize. Following treatment in accordance with the invention, plants remain amenable to self fertilization, thereby allowing the efficient isolation of doubled progeny plants.

  11. Method for detecting biomolecules

    DOE Patents [OSTI]

    Huo, Qisheng (Albuquerque, NM); Liu, Jun (Albuquerque, NM)

    2008-08-12T23:59:59.000Z

    A method for detecting and measuring the concentration of biomolecules in solution, utilizing a conducting electrode in contact with a solution containing target biomolecules, with a film with controllable pore size distribution characteristics applied to at least one surface of the conducting electrode. The film is functionalized with probe molecules that chemically interact with the target biomolecules at the film surface, blocking indicator molecules present in solution from diffusing from the solution to the electrode, thereby changing the electrochemical response of the electrode

  12. Method for scavenging mercury

    DOE Patents [OSTI]

    Chang, Shih-ger (El Cerrito, CA); Liu, Shou-heng (Kaohsiung, TW); Liu, Zhao-rong (Beijing, CN); Yan, Naiqiang (Berkeley, CA)

    2009-01-20T23:59:59.000Z

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting of flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  13. Method for scavenging mercury

    DOE Patents [OSTI]

    Chang, Shih-Ger (El Cerrito, CA); Liu, Shou-Heng (Kaohsiung, TW); Liu, Zhao-Rong (Beijing, CN); Yan, Naiqiang (Berkeley, CA)

    2011-08-30T23:59:59.000Z

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting of flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  14. Method for scavenging mercury

    DOE Patents [OSTI]

    Chang, Shih-ger (El Cerrito, CA); Liu, Shou-heng (Kaohsiung, TW); Liu, Zhao-rong (Bejing, CN); Yan, Naiqiang (Burkeley, CA)

    2010-07-13T23:59:59.000Z

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  15. Method for making nanomaterials

    DOE Patents [OSTI]

    Fan, Hongyou; Wu, Huimeng

    2013-06-04T23:59:59.000Z

    A method of making a nanostructure by preparing a face centered cubic-ordered metal nanoparticle film from metal nanoparticles, such as gold and silver nanoparticles, exerting a hydrostatic pressure upon the film at pressures of several gigapascals, followed by applying a non-hydrostatic stress perpendicularly at a pressure greater than approximately 10 GPA to form an array of nanowires with individual nanowires having a relatively uniform length, average diameter and density.

  16. Vapor spill monitoring method

    DOE Patents [OSTI]

    Bianchini, Gregory M. (Livermore, CA); McRae, Thomas G. (Livermore, CA)

    1985-01-01T23:59:59.000Z

    Method for continuous sampling of liquified natural gas effluent from a spill pipe, vaporizing the cold liquified natural gas, and feeding the vaporized gas into an infrared detector to measure the gas composition. The apparatus utilizes a probe having an inner channel for receiving samples of liquified natural gas and a surrounding water jacket through which warm water is flowed to flash vaporize the liquified natural gas.

  17. Method of casting aerogels

    DOE Patents [OSTI]

    Poco, John F. (Livermore, CA)

    1993-01-01T23:59:59.000Z

    The invention describes a method for making monolithic castings of transparent silica aerogel with densities in the range from 0.001 g/cm.sup.3 to 0.6 g/cm.sup.3. Various shapes of aerogels are cast in flexible polymer molds which facilitate removal and eliminate irregular surfaces. Mold dimensions are preselected to account for shrinkage of alcogel which occurs during the drying step of supercritical extraction of solvent.

  18. Method of casting aerogels

    DOE Patents [OSTI]

    Poco, J.F.

    1993-09-07T23:59:59.000Z

    The invention describes a method for making monolithic castings of transparent silica aerogel with densities in the range from 0.001 g/cm[sup 3] to 0.6 g/cm[sup 3]. Various shapes of aerogels are cast in flexible polymer molds which facilitate removal and eliminate irregular surfaces. Mold dimensions are preselected to account for shrinkage of aerogel which occurs during the drying step of supercritical extraction of solvent. 2 figures.

  19. Method of dehydrocyclizing alkanes

    SciTech Connect (OSTI)

    Buss, W.C.; Hughes, T.R.

    1984-03-06T23:59:59.000Z

    A method of dehydrocyclizing alkanes is disclosed wherein the alkanes are contacted with a catalyst containing a large-pore zeolite, a Group VIII metal, and an alkaline earth metal. The amount of Group VIII metal and the amount of alkaline earth metal present in the catalyst are adjusted so that the selectivity for n-hexane of the dehydrocyclization reaction is greater than 60%.

  20. Bayesian method for testing TTBT compliance with unknown intercept and slope. Scientific report number 101

    SciTech Connect (OSTI)

    Baek, J.; Gray, H.L.; McCartor, G.D.; Woodward, W.A.

    1992-09-19T23:59:59.000Z

    In this report the authors examine the Bayesian method for testing for compliance to a given threshold studies by Nicholson, Mensing and Gray. It is noted that although this test and accompanying confidence intervals are valid for single event, it is incorrect to apply it or the confidence intervals to repeated events at the same site unless the number of calibration events is large. Since in any foreseeable future the number of calibration events is likely to be small, this report studies the applicability of the Bayesian test in this case. The results suggest that in many instances the Bayesian method examined here should be used on repeated events with caution if the number of calibration events is less than three.