Sample records for radiation csr model

  1. First observations of short wavelength coherent synchrotron radiation (CSR) at BC3

    E-Print Network [OSTI]

    First observations of short wavelength coherent synchrotron radiation (CSR) at BC3 Christopher-FLA) short wavelength CSR at BC3 11th December 2007 1 / 26 #12;Outline 1 Motivation CSR at BC3 End Christopher Behrens (DESY-FLA) short wavelength CSR at BC3 11th December 2007 2 / 26 #12

  2. CSR SHIELDING EXPERIMENT

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

    triplets are essential elements of CSR shielding experiment beamline setup. e - e - e - BPMflag image HES image Dispersion function minimized in the dipole where shielding plates...

  3. Cyclotron subharmonics resonant (CSR) heating

    SciTech Connect (OSTI)

    Abe, H.

    1994-01-01T23:59:59.000Z

    The cyclotron subharmonics resonant (CSR) heating mechanism is studied using particle simulation codes with an emphasis on the relationship between CSR and the nonlinear Landua damping.

  4. Coherent Synchrotron Radiation Analysis

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

    Upton, NY 11973, USA Abstract Coherent Synchrotron Radiation (CSR) effects in bunch compressors are analyzed. Schemes for reducing the CSR effects are presented. 1 INTRODUCTION...

  5. CSR in the SuperKEKB Damping Ring

    SciTech Connect (OSTI)

    Zhou, Demin; /KEK, Tsukuba; Abe, Tetsuo; /KEK, Tsukuba; Ikeda, Hitomi; /KEK, Tsukuba; Kikuchi, Mitsuo; /KEK, Tsukuba; Ohmi, Kazuhito; /KEK, Tsukuba; Oide, Katsunobu; /KEK, Tsukuba; Shibata, Kyo; /KEK, Tsukuba; Tobiyama, Makoto; /KEK, Tsukuba; Stupakov, Gennady; /SLAC

    2012-07-06T23:59:59.000Z

    Coherent synchrotron radiation (CSR) is generated when a bunched beam traverses a dipole magnet or a wiggler/undulator. It can degrade the beam quality in both storage rings and linacs through enhancing the beam energy spread and lengthening the bunch length, even cause single-bunch microwave instabilities. Using several methods, CSR impedances in the positron damping ring (DR) of the SuperKEKB which is under design were calculated. From the impedances due to CSR, resistive wall and various vacuum components, quasi-Green function wake potentials were constructed and used in simulations of Particle-In-Cell (PIC) tracking. We present the CSR related results in this paper.

  6. Solar Radiation Modeling and Measurements for Renewable Energy Applications: Data and Model Quality; Preprint

    SciTech Connect (OSTI)

    Myers, D. R.

    2003-03-01T23:59:59.000Z

    Measurement and modeling of broadband and spectral terrestrial solar radiation is important for the evaluation and deployment of solar renewable energy systems. We discuss recent developments in the calibration of broadband solar radiometric instrumentation and improving broadband solar radiation measurement accuracy. An improved diffuse sky reference and radiometer calibration and characterization software and for outdoor pyranometer calibrations is outlined. Several broadband solar radiation model approaches, including some developed at the National Renewable Energy Laboratory, for estimating direct beam, total hemispherical and diffuse sky radiation are briefly reviewed. The latter include the Bird clear sky model for global, direct beam, and diffuse terrestrial solar radiation; the Direct Insolation Simulation Code (DISC) for estimating direct beam radiation from global measurements; and the METSTAT (Meteorological and Statistical) and Climatological Solar Radiation (CSR) models that estimate solar radiation from meteorological data. We conclude that currently the best model uncertainties are representative of the uncertainty in measured data.

  7. CSR Press Release Submitted by

    E-Print Network [OSTI]

    CSR Press Release Submitted by: Categories: Posted: Energy Efficiency Listed as the Top Sustainability Issue New report says companies that take sustainability through an integrated approach are more likely to achieve their desired outcomes. Envido Sustainability, Environment Jul 30, 2010 ­ 11:48 AM EST

  8. A Model Describing Stable Coherent Synchrotron Radiation in Storage Rings F. Sannibale,* J. M. Byrd, A. Loftsdottir,

    E-Print Network [OSTI]

    , Berkeley, California 94720, USA M. Abo-Bakr, J. Feikes, K. Holldack, P. Kuske, and G. Wu¨stefeld BESSY mb of CSR at the BESSY II storage ring. We also use this model to optimize the performance of a source observation of steady state CSR when the BESSY II storage ring was tuned into a special low momentum

  9. CSR Fields: Direct Numerical Solution of the Maxwell___s Equation

    SciTech Connect (OSTI)

    Novokhatski, A.; /SLAC

    2011-06-22T23:59:59.000Z

    We discuss the properties of the coherent electromagnetic fields of a very short, ultra-relativistic bunch in a rectangular vacuum chamber inside a bending magnet. The analysis is based on the results of a direct numerical solution of Maxwell's equations together with Newton's equations. We use a new dispersion-free time-domain algorithm which employs a more efficient use of finite element mesh techniques and hence produces self-consistent and stable solutions for very short bunches. We investigate the fine structure of the CSR fields including coherent edge radiation. This approach should be useful in the study of existing and future concepts of particle accelerators and ultrafast coherent light sources. The coherent synchrotron radiation (CSR) fields have a strong action on the beam dynamics of very short bunches, which are moving in the bends of all kinds of magnetic elements. They are responsible for additional energy loss and energy spread; micro bunching and beam emittance growth. These fields may bound the efficiency of damping rings, electron-positron colliders and ultrafast coherent light sources, where high peak currents and very short bunches are envisioned. This is relevant to most high-brightness beam applications. On the other hand these fields together with transition radiation fields can be used for beam diagnostics or even as a powerful resource of THz radiation. A history of the study of CSR and a good collection of references can be found in [1]. Electromagnetic theory suggests several methods on how to calculate CSR fields. The most popular method is to use Lienard-Wiechert potentials. Other approach is to solve numerically the approximate equations, which are a Schrodinger type equation. These numerical methods are described in [2]. We suggest that a direct solution of Maxwell's equations together with Newton's equations can describe the detailed structure of the CSR fields [3].

  10. Measurement and simulation of the impact of coherent synchrotron radiation on the Jefferson Laboratory energy recovery linac electron beam

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

    Hall, C C.; Biedron, S G.; Edelen, A L.; Milton, S V.; Benson, S; Douglas, D; Li, R; Tennant, C D.; Carlsten, B E.

    2015-03-01T23:59:59.000Z

    In an experiment conducted on the Jefferson Laboratory IR free-electron laser driver, the effects of coherent synchrotron radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR recirculator. Here we examine the impact of CSR on the average energy loss as a function of bunch compression as well as the impact of CSR on the energy spectrum of the bunch. Simulation of beam dynamics in the machine, including the one-dimensional CSR model, shows very good agreement with themore »measured effect of CSR on the average energy loss as a function of compression. Finally, a well-defined structure is observed in the energy spectrum with a feature in the spectrum that varies as a function of the compression. This effect is examined in simulations, as well, and a simple explanation for the variation is proposed.« less

  11. Modeling radiation characteristics of semitransparent media

    E-Print Network [OSTI]

    Pilon, Laurent

    and Viskanta8 have proposed a model for the effective radiation characteristics of glass foams. Their analysis

  12. July 10, 2014 CSR Computer Policy Statement

    E-Print Network [OSTI]

    Lightsey, Glenn

    and/or administrator access to all computers on the CSR network. Users cannot be allowed to have root to a computer account for the purpose of doing professional research, administrative tasks, or other work and/or administrator access unless it can be specifically shown that it is necessary for them to carry

  13. June 23, 2008 CSR Computer Policy Statement

    E-Print Network [OSTI]

    Lightsey, Glenn

    and/or administrator access to all computers on the CSR network. Users cannot be allowed to have root to a computer account for the purpose of doing professional research, administrative tasks, or other work and/or administrator access unless it can be specifically shown that it is necessary for them to carry

  14. Compressor and Chicane Radiation Studies at the ATF

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

    effects (CER, CSR, CTR) from short beams - Bunch length correlated to emitted radiation frequency spectrum - Advanced reconstruction tools * Single-shot capability -...

  15. Density Functional Theory Models for Radiation Damage

    E-Print Network [OSTI]

    Density Functional Theory Models for Radiation Damage S.L. Dudarev EURATOM/CCFE Fusion Association and informative as the most advanced experimental techniques developed for the observation of radiation damage investigation and assessment of radiation damage effects, offering new insight into the origin of temperature

  16. affairs adjustment csr: Topics by E-print Network

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

    CSR Microbunching Zhirong Huang and Kwang302 Advanced Photon Source Derivation: KJK Application: ZRH Based on ZRH & KJK Main References SSY (Saldin, Schneidmiller,...

  17. Effects of CSR Generated from Upstream Bends in a Laser Plasma Storage Ring

    SciTech Connect (OSTI)

    Mitchell, C.; Qiang, J.; Venturini, M.

    2013-08-28T23:59:59.000Z

    The recent proposal [1] of a Laser Plasma Storage Ring (LPSR) envisions the use of a laser-plasma (LP) acceleration module to inject an electron beam into a compact 500 MeV storage ring. Electron bunches generated by LP methods are naturally very short (tens of femtoseconds), presenting peak currents on the order of 10 kA or higher. Of obvious concern is the impact of collective effects and in particular Coherent Synchrotron Radiation (CSR) on the beam dynamics in the storage ring. Available simulation codes (e.g. Elegant [2]) usually include transient CSR effects but neglect the contribution of radiation emitted from trailing magnets. In a compact storage ring, with dipole magnets close to each other, cross talking between different magnets could in principle be important.In this note we investigate this effect for the proposed LPSR and show that, in fact, this effect is relatively small. However our analysis also indicates that CSR effects in general would be quite strong and deserve a a careful study.

  18. The greenwashing machine: Is CSR more than communication?

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and the huge challenge raised by climate change may explain a rising concern by the consumers and thus a newThe greenwashing machine: Is CSR more than communication? Rémi BAZILLIER and Julien VAUDAY July to their sales and/or profits. However, it could be that communicating on CSR represents by itself a good

  19. The dynamic radiation environment assimilation model (DREAM)

    SciTech Connect (OSTI)

    Reeves, Geoffrey D [Los Alamos National Laboratory; Koller, Josef [Los Alamos National Laboratory; Tokar, Robert L [Los Alamos National Laboratory; Chen, Yue [Los Alamos National Laboratory; Henderson, Michael G [Los Alamos National Laboratory; Friedel, Reiner H [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    The Dynamic Radiation Environment Assimilation Model (DREAM) is a 3-year effort sponsored by the US Department of Energy to provide global, retrospective, or real-time specification of the natural and potential nuclear radiation environments. The DREAM model uses Kalman filtering techniques that combine the strengths of new physical models of the radiation belts with electron observations from long-term satellite systems such as GPS and geosynchronous systems. DREAM includes a physics model for the production and long-term evolution of artificial radiation belts from high altitude nuclear explosions. DREAM has been validated against satellites in arbitrary orbits and consistently produces more accurate results than existing models. Tools for user-specific applications and graphical displays are in beta testing and a real-time version of DREAM has been in continuous operation since November 2009.

  20. Multiscale Modeling of Radiation Damage in

    E-Print Network [OSTI]

    Multiscale Modeling of Radiation Damage in Fusion Reactor Materials Brian D. Wirth, R.J. Kurtz-7405-Eng-48. #12;Presentation overview · Introduction to fusion reactor materials and radiation damage. tailor He HFIR isotopic tailor He HFIR target/RB He appmHe displacement damage (dpa) ffuussiioonn

  1. Application of Improved Radiation Modeling to General Circulation Models

    SciTech Connect (OSTI)

    Michael J Iacono

    2011-04-07T23:59:59.000Z

    This research has accomplished its primary objectives of developing accurate and efficient radiation codes, validating them with measurements and higher resolution models, and providing these advancements to the global modeling community to enhance the treatment of cloud and radiative processes in weather and climate prediction models. A critical component of this research has been the development of the longwave and shortwave broadband radiative transfer code for general circulation model (GCM) applications, RRTMG, which is based on the single-column reference code, RRTM, also developed at AER. RRTMG is a rigorously tested radiation model that retains a considerable level of accuracy relative to higher resolution models and measurements despite the performance enhancements that have made it possible to apply this radiation code successfully to global dynamical models. This model includes the radiative effects of all significant atmospheric gases, and it treats the absorption and scattering from liquid and ice clouds and aerosols. RRTMG also includes a statistical technique for representing small-scale cloud variability, such as cloud fraction and the vertical overlap of clouds, which has been shown to improve cloud radiative forcing in global models. This development approach has provided a direct link from observations to the enhanced radiative transfer provided by RRTMG for application to GCMs. Recent comparison of existing climate model radiation codes with high resolution models has documented the improved radiative forcing capability provided by RRTMG, especially at the surface, relative to other GCM radiation models. Due to its high accuracy, its connection to observations, and its computational efficiency, RRTMG has been implemented operationally in many national and international dynamical models to provide validated radiative transfer for improving weather forecasts and enhancing the prediction of global climate change.

  2. adult cancer csr: Topics by E-print Network

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

    Ablayev; Bob Coecke; Alexander Vasiliev 2011-03-09 25 Revue Sciences de Gestion, n 80, p. Exploring the relationship between CSR and Physics Websites Summary: practices can lead to...

  3. Using Geostationary Earth Radiation Budget dataUsing Geostationary Earth Radiation Budget data to evaluate global models and radiative processes

    E-Print Network [OSTI]

    cloud cover r.p.allan@reading.ac.uk© University of Reading 20108 #12;Radiative bias: climate models estimate radiative effect of contrail cirrus:contrail cirrus: LW ~ 40 Wm-2 SW up to 80 Wm-2 rUsing Geostationary Earth Radiation Budget dataUsing Geostationary Earth Radiation Budget data

  4. A BAYESIAN MODEL COMMITTEE APPROACH TO FORECASTING GLOBAL SOLAR RADIATION

    E-Print Network [OSTI]

    Boyer, Edmond

    1 A BAYESIAN MODEL COMMITTEE APPROACH TO FORECASTING GLOBAL SOLAR RADIATION in the realm of solar radiation forecasting. In this work, two forecasting models: Autoregressive Moving. The very first results show an improvement brought by this approach. 1. INTRODUCTION Solar radiation

  5. An adaptive radiation model for the origin of new gene functions

    E-Print Network [OSTI]

    Francino, M. Pilar

    2005-01-01T23:59:59.000Z

    An adaptive radiation model for the origin of new genePreadaptation Adaptive radiation Competition among closefor a specific niche Adaptive radiation model Adaptive gene

  6. Longitudinal pulse shaping for the suppression of coherent synchrotron radiation-induced emittance growth

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

    Mitchell, Chad; Qiang, Ji; Emma, Paul

    2013-06-01T23:59:59.000Z

    The damaging effect of coherent synchrotron radiation (CSR) on the emittance and energy spread of high-energy beams in accelerator light sources can significantly constrain the machine design and performance. We propose a mitigation approach in which the dynamical effect of the longitudinal component of CSR is suppressed by appropriately preparing the initial longitudinal current profile of the beam. In a chicane, a linear theory for the mechanism of CSR-induced emittance growth is used to demonstrate how this procedure can produce a beam whose core experiences suppressed transverse emittance growth. The dynamics of such a beam is illustrated for the Berlin-Zeuthen CSR benchmark chicane.

  7. Quantum Black Hole Model and Hawking's Radiation

    E-Print Network [OSTI]

    V. A. Berezin

    1996-02-12T23:59:59.000Z

    The black hole model with a self-gravitating charged spherical symmetric dust thin shell as a source is considered. The Schroedinger-type equation for such a model is derived. This equation appeared to be a finite differences equation. A theory of such an equation is developed and general solution is found and investigated in details. The discrete spectrum of the bound state energy levels is obtained. All the eigenvalues appeared to be infinitely degenerate. The ground state wave functions are evaluated explicitly. The quantum black hole states are selected and investigated. It is shown that the obtained black hole mass spectrum is compatible with the existence of Hawking's radiation in the limit of low temperatures both for large and nearly extreme Reissner-Nordstrom black holes. The above mentioned infinite degeneracy of the mass (energy) eigenvalues may appeared helpful in resolving the well known information paradox in the black hole physics.

  8. The PR in CSR: Assessing Perceptions of Partnerships versus Donations in Corporate Social Responsibility Initiatives

    E-Print Network [OSTI]

    Walton, Michaella Raquel

    2014-08-05T23:59:59.000Z

    CHAPTER I INTRODUCTION Corporate Social Responsibility Pervasiveness Corporate Social Responsibility (CSR) initiatives have become more common in the last decade than any other time in history (Becker-Olsen & Hill, 2005). Though CSR campaigns were... competition and higher initiative expectations from the public (Cheney, Roper & May, 2007). Research suggests that as CSR becomes more pervasive among corporations, individuals have become more skeptical of the effectiveness of these initiatives (Becker...

  9. adjustment csr 1975-2005: Topics by E-print Network

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

    not used in the official experiment, including experiments with perplexity minimization, Maximum Entropy mod- eling and parsing. 1. Introduction This paper 18 Proceedings CSR...

  10. 3D Atmospheric Radiative Transfer for Cloud System-Resolving Models: Forward Modelling and Observations

    SciTech Connect (OSTI)

    Howard Barker; Jason Cole

    2012-05-17T23:59:59.000Z

    Utilization of cloud-resolving models and multi-dimensional radiative transfer models to investigate the importance of 3D radiation effects on the numerical simulation of cloud fields and their properties.

  11. Modelling of Radiative Transfer in Light Sources

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    . . . . . . . . . . . . . . . 30 2.5.3 Temperature distribution . . . . . . . . . . . . . . . . . . . . . . . . . 32 2-X radiative transition that is responsible for the sulfur lamp's bright sun-like spectrum #12;Contents 1

  12. Corporate social responsibility (CSR) : responsibility or Innovation? : an analysis of the feedback between CSR activities and the expectations placed upon corporations

    E-Print Network [OSTI]

    Rodriguez, Adrian Xavier

    2010-01-01T23:59:59.000Z

    This thesis uses case study and interview data to present a framework for analyzing corporate behavior in order to define corporate social responsibility (CSR). It answers the question: Can corporations tie corporate social ...

  13. Hunan CSR Huanghai Electric Automobile Holding | 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 You are being directedAnnual SiteofEvaluatingGroup | Open EnergyInformationHorizonEnergyHubeiHumus Group JumpHunan CSR

  14. Canopy radiation transmission for an energy balance snowmelt model

    E-Print Network [OSTI]

    Tarboton, David

    Canopy radiation transmission for an energy balance snowmelt model Vinod Mahat1 and David G deep canopy solution. This solution enhances capability for modeling energy balance processes in a distributed energy balance snowmelt model and results compared with observations made in three different

  15. A MODEL FOR PRODUCING STABLE, BROADBAND TERAHERTZ COHERENT SYNCHROTRON RADIATION IN STORAGE RINGS*

    E-Print Network [OSTI]

    that steady state CSR has been observed for the first time in the BESSY-II storage ring [2, 3]. Coupled be found that the BESSY-II CSR emission belongs to this category. In fact, streak camera measurements for Gaussian bunches and indicating the presence of distorted distributions. Attractive features of the BESSY

  16. Radiative and Auger decay data for modelling nickel K lines

    E-Print Network [OSTI]

    P. Palmeri; P. Quinet; C. Mendoza; M. A. Bautista; J. Garcia; M. C. Witthoeft; T. R. Kallman

    2008-06-06T23:59:59.000Z

    Radiative and Auger decay data have been calculated for modelling the K lines in ions of the nickel isonuclear sequence, from Ni$^+$ up to Ni$^{27+}$. Level energies, transition wavelengths, radiative transition probabilities, and radiative and Auger widths have been determined using Cowan's Hartree--Fock with Relativistic corrections (HFR) method. Auger widths for the third-row ions (Ni$^+$--Ni$^{10+}$) have been computed using single-configuration average (SCA) compact formulae. Results are compared with data sets computed with the AUTOSTRUCTURE and MCDF atomic structure codes and with available experimental and theoretical values, mainly in highly ionized ions and in the solid state.

  17. A model code for the radiative theta pinch

    SciTech Connect (OSTI)

    Lee, S., E-mail: leesing@optusnet.com.au [INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 Australia (Australia); Physics Department, University of Malaya, Kuala Lumpur (Malaysia); Saw, S. H. [INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 Australia (Australia); Lee, P. C. K. [Nanyang Technological University, National Institute of Education, Singapore 637616 (Singapore); Akel, M. [Department of Physics, Atomic Energy Commission, Damascus, P. O. Box 6091, Damascus (Syrian Arab Republic); Damideh, V. [INTI International University, 71800 Nilai (Malaysia); Khattak, N. A. D. [Department of Physics, Gomal University, Dera Ismail Khan (Pakistan); Mongkolnavin, R.; Paosawatyanyong, B. [Department of Physics, Faculty of Science, Chulalongkorn University, Bangkok 10140 (Thailand)

    2014-07-15T23:59:59.000Z

    A model for the theta pinch is presented with three modelled phases of radial inward shock phase, reflected shock phase, and a final pinch phase. The governing equations for the phases are derived incorporating thermodynamics and radiation and radiation-coupled dynamics in the pinch phase. A code is written incorporating correction for the effects of transit delay of small disturbing speeds and the effects of plasma self-absorption on the radiation. Two model parameters are incorporated into the model, the coupling coefficient f between the primary loop current and the induced plasma current and the mass swept up factor f{sub m}. These values are taken from experiments carried out in the Chulalongkorn theta pinch.

  18. Radiative Transfer Models for Gamma-Ray Bursts

    E-Print Network [OSTI]

    Vurm, Indrek

    2015-01-01T23:59:59.000Z

    We present global radiative transfer models for heated relativistic jets. The simulations include all relevant radiative processes, starting deep in the opaque zone and following the evolution of radiation to and beyond the photosphere of the jet. The transfer models are compared with three gamma-ray bursts GRB 990123, GRB 090902B, and GRB 130427A, which have well-measured and different spectra. The models provide good fits to the observed spectra in all three cases. The fits give estimates for the jet magnetization parameter $\\varepsilon_{\\rm B}$ and the Lorentz factor $\\Gamma$. In the small sample of three bursts, $\\varepsilon_{\\rm B}$ varies between 0.01 and 0.1, and $\\Gamma$ varies between 340 and 1200.

  19. An adaptive radiation model for the origin of new gene functions

    E-Print Network [OSTI]

    Francino, M. Pilar

    2004-01-01T23:59:59.000Z

    Foster, P.L. Adaptive radiation of a frameshift mutation inThe Ecology of Adaptive Radiation, (Oxford University Press,18 th , 2004) An adaptive radiation model for the origin of

  20. Curve fitting methods for solar radiation data modeling

    SciTech Connect (OSTI)

    Karim, Samsul Ariffin Abdul, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my; Singh, Balbir Singh Mahinder, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my [Department of Fundamental and Applied Sciences, Faculty of Sciences and Information Technology, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak Darul Ridzuan (Malaysia)

    2014-10-24T23:59:59.000Z

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R{sup 2}. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods.

  1. Geosynchronous orbit determination using space surveillance network observations and improved radiative force modeling

    E-Print Network [OSTI]

    Lyon, Richard Harry, 1981-

    2004-01-01T23:59:59.000Z

    Correct modeling of the space environment, including radiative forces, is an important aspect of space situational awareness for geostationary (GEO) spacecraft. Solar radiation pressure has traditionally been modeled using ...

  2. Spreader-Bar Radiation Detection System Enhancements: A Modeling and Simulation Study

    SciTech Connect (OSTI)

    Ely, James H.; Ashbaker, Eric D.; Batdorf, Michael T.; Baciak, James E.; Hensley, Walter K.; Jarman, Kenneth D.; Robinson, Sean M.; Sandness, Gerald A.; Schweppe, John E.

    2012-11-13T23:59:59.000Z

    This report provides the modeling and simulation results of the investigation of enhanced spreader bar radiation detection systems.

  3. Modeling and Analysis of Solar Radiation Potentials on Building Rooftops

    SciTech Connect (OSTI)

    Omitaomu, Olufemi A [ORNL; Kodysh, Jeffrey B [ORNL; Bhaduri, Budhendra L [ORNL

    2012-01-01T23:59:59.000Z

    The active application of photovoltaic for electricity generation could effectively transform neighborhoods and commercial districts into small, localized power plants. This application, however, relies heavily on an accurate estimation of the amount of solar radiation that is available on individual building rooftops. While many solar energy maps exist at higher spatial resolution for concentrated solar energy applications, the data from these maps are not suitable for roof-mounted photovoltaic for several reasons, including lack of data at the appropriate spatial resolution and lack of integration of building-specific characteristics into the models used to generate the maps. To address this problem, we have developed a modeling framework for estimating solar radiation potentials on individual building rooftops that is suitable for utility-scale applications as well as building-specific applications. The framework uses light detection and ranging (LIDAR) data at approximately 1-meter horizontal resolution and 0.3-meter vertical resolution as input for modeling a large number of buildings quickly. One of the strengths of this framework is the ability to parallelize its implementation. Furthermore, the framework accounts for building specific characteristics, such as roof slope, roof aspect, and shadowing effects, that are critical to roof-mounted photovoltaic systems. The resulting data has helped us to identify the so-called solar panel sweet spots on individual building rooftops and obtain accurate statistics of the variation in solar radiation as a function of time of year and geographical location.

  4. Scalar potential model of the CMB radiation temperature

    E-Print Network [OSTI]

    John C. Hodge

    2006-03-06T23:59:59.000Z

    A derivation of a theoretical, time average, cosmic microwave background (CMB), Planckian temperature V of the universe remains a challenge. A scalar potential model (SPM) that resulted from considerations of galaxy cells is applied to deriving a value for V. The heat equation is solved for a cell with the boundary conditions of SPM Source and Sink characteristics, with simplified cell characteristics, and with zero initial temperature. The universe is a collection of cells. The CMB radiation is black body radiation with the cells acting as radiators and absorbers. Conventional thermodynamics is applied to calculate V = 2.718 K. The temperature and matter content of cells are finely controlled by a feedback mechanism. Because time is required for matter to flow from Sources to Sinks, the radiation temperature of cells cycles about V after an initial growth phase. If the universe is like an ideal gas in free expansion and is not in thermal equilibrium, then the pressure and volume follow the measured CMB temperature vm = 2.725 K. Therefore, increasing vm >V equates to an expansion pressure on matter and expanding volume.

  5. A simplified physical model for assessing solar radiation over Brazil using GOES 8 visible imagery

    E-Print Network [OSTI]

    A simplified physical model for assessing solar radiation over Brazil using GOES 8 visible imagery; published 30 January 2004. [1] Solar radiation assessment by satellite is constrained by physical Composition and Structure: Transmission and scattering of radiation; KEYWORDS: solar radiation, satellite

  6. Coupled Deterministic-Monte Carlo Transport for Radiation Portal Modeling

    SciTech Connect (OSTI)

    Smith, Leon E.; Miller, Erin A.; Wittman, Richard S.; Shaver, Mark W.

    2008-01-14T23:59:59.000Z

    Radiation portal monitors are being deployed, both domestically and internationally, to detect illicit movement of radiological materials concealed in cargo. Evaluation of the current and next generations of these radiation portal monitor (RPM) technologies is an ongoing process. 'Injection studies' that superimpose, computationally, the signature from threat materials onto empirical vehicle profiles collected at ports of entry, are often a component of the RPM evaluation process. However, measurement of realistic threat devices can be both expensive and time-consuming. Radiation transport methods that can predict the response of radiation detection sensors with high fidelity, and do so rapidly enough to allow the modeling of many different threat-source configurations, are a cornerstone of reliable evaluation results. Monte Carlo methods have been the primary tool of the detection community for these kinds of calculations, in no small part because they are particularly effective for calculating pulse-height spectra in gamma-ray spectrometers. However, computational times for problems with a high degree of scattering and absorption can be extremely long. Deterministic codes that discretize the transport in space, angle, and energy offer potential advantages in computational efficiency for these same kinds of problems, but the pulse-height calculations needed to predict gamma-ray spectrometer response are not readily accessible. These complementary strengths for radiation detection scenarios suggest that coupling Monte Carlo and deterministic methods could be beneficial in terms of computational efficiency. Pacific Northwest National Laboratory and its collaborators are developing a RAdiation Detection Scenario Analysis Toolbox (RADSAT) founded on this coupling approach. The deterministic core of RADSAT is Attila, a three-dimensional, tetrahedral-mesh code originally developed by Los Alamos National Laboratory, and since expanded and refined by Transpire, Inc. [1]. MCNP5 is used to calculate sensor pulse-height tallies. RADSAT methods, including adaptive, problem-specific energy-group creation, ray-effect mitigation strategies and the porting of deterministic angular flux to MCNP for individual particle creation are described in [2][3][4]. This paper discusses the application of RADSAT to the modeling of gamma-ray spectrometers in RPMs.

  7. APPLICATIONS OF THE PHOTONUCLEAR FRAGMENTATION MODEL TO RADIATION PROTECTION PROBLEMS

    SciTech Connect (OSTI)

    Pavel Degtiarenko

    1996-01-01T23:59:59.000Z

    In order to provide radiation protection systems for high energy electron accelerators it is necessary to define the yields of hadrons produced when the electron beam interacts with a fixed target. In practical terms this will occur when any beam or fraction of the beam is lost from the accelerator orbit or when any fraction of the beam is intercepted by a target inserted in the path of the beam or when the beam is totally absorbed by a beam dump. The electron and gamma yields from these interactions are well characterized and amenable to calculation utilizing Monte Carlo shower codes. However, the yield of hadrons has been less well defined. Neutron production has received most attention because of its importance to radiation shielding. Production mechanisms such as the giant dipole and the quasi-deuteron resonances have provided valuable information for total neutron yields for electron beams at energies less than about 400 MeV. For electron beams at energies extending to 10 GeV it is necessary to include the higher energy resonance structures and the various intranuclear production channels that are available for the production of higher energy neutrons. The production model described in this paper permits the calculation of laboratory angle and energy of all hadrons produced when an electron beam of energy between 100 MeV and 10 GeV interacts with a fixed target. This model can be used as an event generator for Monte Carlo codes used for many radiation protection purposes including calculation of radiation shielding.

  8. Radiation Modeling In Fluid Flow Iain D. Boyd

    E-Print Network [OSTI]

    Wang, Wei

    Collector #12;4 Fundamentals of Radiation (1) · All matter with non-zero temperature emits thermal radiation with energy flux given by the Stefan-Boltzmann Law: e.g., Sun: T=5800 K, total radiated power = 4 distribution (Planck spectrum) !q =T 4 W/m2 #12;5 Planck Radiation Spectrum #12;6 Solar Radiation Spectrum

  9. Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal waters

    E-Print Network [OSTI]

    Lee, Zhongping

    Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal waters in the upper ocean, the vertical distribution of solar radiation (ESR) in the shortwave domain plays (2005), Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal

  10. High-energy radiation damage in zirconia: modeling results ....

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

    zirconia in intense radiation environments. Citation: Zarkadoula E, R Devanathan, WJ Weber, M Seaton, I Todorov, K Nordlund, MT Dove, and K Trachenko.2014."High-energy radiation...

  11. Research SummaryForest Research Monitoring and evaluating Quality of Life for CSR 07

    E-Print Network [OSTI]

    (Target 1), and increases management activities), quality of experience and personal in visitsResearch SummaryForest Research Monitoring and evaluating Quality of Life for CSR 07 As part corporate Quality of Life (QoL) targets, giving rise to the Monitoring and Evaluating Quality of Life

  12. Compendium of Material Composition Data for Radiation Transport Modeling

    SciTech Connect (OSTI)

    McConn, Ronald J.; Gesh, Christopher J.; Pagh, Richard T.; Rucker, Robert A.; Williams III, Robert

    2011-03-04T23:59:59.000Z

    Introduction Meaningful simulations of radiation transport applications require realistic definitions of material composition and densities. When seeking that information for applications in fields such as homeland security, radiation shielding and protection, and criticality safety, researchers usually encounter a variety of materials for which elemental compositions are not readily available or densities are not defined. Publication of the Compendium of Material Composition Data for Radiation Transport Modeling, Revision 0, in 2006 was the first step toward mitigating this problem. Revision 0 of this document listed 121 materials, selected mostly from the combined personal libraries of staff at the Pacific Northwest National Laboratory (PNNL), and thus had a scope that was recognized at the time to be limited. Nevertheless, its creation did provide a well-referenced source of some unique or hard-to-define material data in a format that could be used directly in radiation transport calculations being performed at PNNL. Moreover, having a single common set of material definitions also helped to standardize at least one aspect of the various modeling efforts across the laboratory by providing separate researchers the ability to compare different model results using a common basis of materials. The authors of the 2006 compendium understood that, depending on its use and feedback, the compendium would need to be revised to correct errors or inconsistencies in the data for the original 121 materials, as well as to increase (per users suggestions) the number of materials listed. This 2010 revision of the compendium has accomplished both of those objectives. The most obvious change is the increased number of materials from 121 to 372. The not-so-obvious change is the mechanism used to produce the data listed here. The data listed in the 2006 document were compiled, evaluated, entered, and error-checked by a group of individuals essentially by hand, providing no library file or mechanism for revising the data in a consistent and traceable manner. The authors of this revision have addressed that problem by first compiling all of the information (i.e., numbers and references) for all the materials into a single database, maintained at PNNL, that was then used as the basis for this document.

  13. Running of Radiative Neutrino Masses: The Scotogenic Model

    E-Print Network [OSTI]

    Romain Bouchand; Alexander Merle

    2012-04-30T23:59:59.000Z

    We study the renormalization group equations of Ma's scotogenic model, which generates an active neutrino mass at 1-loop level. In addition to other benefits, the main advantage of the mechanism exploited in this model is to lead to a natural loop-suppression of the neutrino mass, and therefore to an explanation for its smallness. However, since the structure of the neutrino mass matrix is altered compared to the ordinary type I seesaw case, the corresponding running is altered as well. We have derived the full set of renormalization group equations for the scotogenic model which, to our knowledge, had not been presented previously in the literature. This set of equations reflects some interesting structural properties of the model, and it is an illustrative example for how the running of neutrino parameters in radiative models is modified compared to models with tree-level mass generation. We also study a simplified numerical example to illustrate some general tendencies of the running. Interestingly, the structure of the RGEs can be exploited such that a bimaximal leptonic mixing pattern at the high-energy scale is translated into a valid mixing pattern at low energies, featuring a large value of \\theta_{13}. This suggests very interesting connections to flavour symmetries.

  14. OUMBE, Armel, WALD, Lucien, BLANC, Philippe, and SCHROEDTER-HOMSCHEIDT, Marion. Exploitation of radiative transfer model for assessing solar radiation: the relative importance of atmospheric

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of radiative transfer model for assessing solar radiation: the relative importance of atmospheric constituents, Germany * Corresponding Author, armel.oumbe@ensmp.fr Abstract Solar radiation is modified in its way: solar radiation, atmospheric optics, satellite images, Heliosat method 1. Introduction A wealth

  15. Nuisance Source Population Modeling for Radiation Detection System Analysis

    SciTech Connect (OSTI)

    Sokkappa, P; Lange, D; Nelson, K; Wheeler, R

    2009-10-05T23:59:59.000Z

    A major challenge facing the prospective deployment of radiation detection systems for homeland security applications is the discrimination of radiological or nuclear 'threat sources' from radioactive, but benign, 'nuisance sources'. Common examples of such nuisance sources include naturally occurring radioactive material (NORM), medical patients who have received radioactive drugs for either diagnostics or treatment, and industrial sources. A sensitive detector that cannot distinguish between 'threat' and 'benign' classes will generate false positives which, if sufficiently frequent, will preclude it from being operationally deployed. In this report, we describe a first-principles physics-based modeling approach that is used to approximate the physical properties and corresponding gamma ray spectral signatures of real nuisance sources. Specific models are proposed for the three nuisance source classes - NORM, medical and industrial. The models can be validated against measured data - that is, energy spectra generated with the model can be compared to actual nuisance source data. We show by example how this is done for NORM and medical sources, using data sets obtained from spectroscopic detector deployments for cargo container screening and urban area traffic screening, respectively. In addition to capturing the range of radioactive signatures of individual nuisance sources, a nuisance source population model must generate sources with a frequency of occurrence consistent with that found in actual movement of goods and people. Measured radiation detection data can indicate these frequencies, but, at present, such data are available only for a very limited set of locations and time periods. In this report, we make more general estimates of frequencies for NORM and medical sources using a range of data sources such as shipping manifests and medical treatment statistics. We also identify potential data sources for industrial source frequencies, but leave the task of estimating these frequencies for future work. Modeling of nuisance source populations is only useful if it helps in understanding detector system performance in real operational environments. Examples of previous studies in which nuisance source models played a key role are briefly discussed. These include screening of in-bound urban traffic and monitoring of shipping containers in transit to U.S. ports.

  16. A spatiotemporal auto-regressive moving average model for solar radiation

    E-Print Network [OSTI]

    Stone, J. V.

    A spatiotemporal auto-regressive moving average model for solar radiation C.A. Glasbey and D 1). Solar radiation, averaged over ten minute intervals, was recorded at each site for two years otherwise there are too many parameters to be estimated. As we wish to simulate solar radiation on a network

  17. Time series modeling and large scale global solar radiation forecasting from geostationary satellites data

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Time series modeling and large scale global solar radiation forecasting from geostationary global solar radiation. In this paper, we use geostationary satellites data to generate 2-D time series of solar radiation for the next hour. The results presented in this paper relate to a particular territory

  18. USING LEARNING MACHINES TO CREATE SOLAR RADIATION MAPS FROM NUMERICAL WEATHER PREDICTION MODELS,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    USING LEARNING MACHINES TO CREATE SOLAR RADIATION MAPS FROM NUMERICAL WEATHER PREDICTION MODELS to develop a methodology to generate solar radiation maps using information from different sources. First with conclusions and next works in the last section. Keywords: Solar Radiation maps, Numerical Weather Predictions

  19. Evaluating the present-day simulation of clouds, precipitation, and radiation in climate models

    E-Print Network [OSTI]

    Robert, Pincus

    , and net cloud radiative effect, projected cloud fraction, and surface precipitation rate) over the globalEvaluating the present-day simulation of clouds, precipitation, and radiation in climate models] This paper describes a set of metrics for evaluating the simulation of clouds, radiation, and precipitation

  20. Compensating effect of the coherent synchrotron radiation in bunch compressors

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

    Jing, Yichao; Hao, Yue; Litvinenko, Vladimir N.

    2013-06-01T23:59:59.000Z

    Typical bunch compression for a high-gain free-electron laser (FEL) requires a large compression ratio. Frequently, this compression is distributed in multiple stages along the beam transport line. However, for a high-gain FEL driven by an energy recovery linac (ERL), compression must be accomplished in a single strong compressor located at the beam line’s end; otherwise the electron beam would be affected severely by coherent synchrotron radiation (CSR) in the ERL’s arcs. In such a scheme, the CSR originating from the strong compressors could greatly degrade the quality of the electron beam. In this paper, we present our design for a bunch compressor that will limit the effect of CSR on the e-beam’s quality. We discuss our findings from a study of such a compressor, and detail its potential for an FEL driven by a multipass ERL developed for the electron-Relativistic Heavy Ion Collider.

  1. Economic analysis: impact of CS/R process on benzene market

    SciTech Connect (OSTI)

    Spielberger, L.; Klein, J.

    1981-05-01T23:59:59.000Z

    Contract No. DE-AC01-78ET10159 (formerly ET-78-C-01-3117) between UOP/SDC and the United States Department of Energy (DOE) requires UOP/SDC to provide specific engineering and technical services to the DOE Office of Coal Processing in support of the Coal Gasification Program. This report covers an economic study on the projected price of benzene through the next decade based on the market factors and production costs. The impact of the CS/R process on the benzene market was evaluated. In addition, the cost of gas from the CS/R process was determined as a function of the byproduct credit for benzene.

  2. Experimental Studies on Coherent Synchrotron Radiation at an Emittance Exchange Beamline

    SciTech Connect (OSTI)

    Thangaraj, J.C.T.; Thurman-Keup, R.; Ruan, J.; Johnson, A.S.; Lumpkin, A.H.; Santucci, J.; /Fermilab

    2012-04-01T23:59:59.000Z

    One of the goals of the Fermilab A0 photoinjector is to experimentally investigate the transverse to longitudinal emittance exchange (EEX) principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR) in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy chirped beam.

  3. Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone

    E-Print Network [OSTI]

    Yakovlev, Vadim

    Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone Shawn M (electromagnetic and thermal) modeling to cover practically valuable scenarios of hybrid (heat radiation is applied to the process of hybrid heating of cylindrical samples of limestone in Ceralink's MAT TM kiln

  4. Interpretation of AIRS Data in Thin Cirrus Atmospheres Based on a Fast Radiative Transfer Model

    E-Print Network [OSTI]

    Liou, K. N.

    Interpretation of AIRS Data in Thin Cirrus Atmospheres Based on a Fast Radiative Transfer Model of California, Los Angeles, Los Angeles, California B. H. KAHN Jet Propulsion Laboratory, California Institute radiative transfer model has been developed for application to cloudy satellite data assimilation

  5. A 3D STOCHASTIC CLOUD MODEL FOR INVESTIGATING THE RADIATIVE PROPERTIES OF INHOMOGENEOUS CIRRUS CLOUDS

    E-Print Network [OSTI]

    Hogan, Robin

    A 3D STOCHASTIC CLOUD MODEL FOR INVESTIGATING THE RADIATIVE PROPERTIES OF INHOMOGENEOUS CIRRUS, Berkshire, United Kingdom 1 INTRODUCTION The importance of ice clouds on the earth's radiation budget for quantifying this effect, and several such models exist for boundary layer clouds, such as those of Cahalan et

  6. Stochastic modeling of the cell killing effect for low- and high-LET radiation

    E-Print Network [OSTI]

    Partouche, Julien

    2005-02-17T23:59:59.000Z

    Theoretical modeling of biological response to radiation describes qualitatively and quantitatively the results of radiobiological effects at the molecular, chromosomal, and cellular level. The repair-misrepair (RMR) model is the radiobiological...

  7. Stochastic modeling of the cell killing effect for low- and high-LET radiation 

    E-Print Network [OSTI]

    Partouche, Julien

    2005-02-17T23:59:59.000Z

    Theoretical modeling of biological response to radiation describes qualitatively and quantitatively the results of radiobiological effects at the molecular, chromosomal, and cellular level. The repair-misrepair (RMR) model ...

  8. Global oceanic rainfall estimation from AMSR-E data based on a radiative transfer model 

    E-Print Network [OSTI]

    Jin, Kyoung-Wook

    2006-04-12T23:59:59.000Z

    An improved physically-based rainfall algorithm was developed using AMSR-E data based on a radiative transfer model. In addition, error models were designed and embedded in the algorithm to assess retrieval errors ...

  9. Normal Tissue Complication Probability Modeling of Radiation-Induced Hypothyroidism After Head-and-Neck Radiation Therapy

    SciTech Connect (OSTI)

    Bakhshandeh, Mohsen [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mahdavi, Seied Rabi Mehdi [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nikoofar, Alireza; Vasheghani, Maryam [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)] [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kazemnejad, Anoshirvan [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

    2013-02-01T23:59:59.000Z

    Purpose: To determine the dose-response relationship of the thyroid for radiation-induced hypothyroidism in head-and-neck radiation therapy, according to 6 normal tissue complication probability models, and to find the best-fit parameters of the models. Methods and Materials: Sixty-five patients treated with primary or postoperative radiation therapy for various cancers in the head-and-neck region were prospectively evaluated. Patient serum samples (tri-iodothyronine, thyroxine, thyroid-stimulating hormone [TSH], free tri-iodothyronine, and free thyroxine) were measured before and at regular time intervals until 1 year after the completion of radiation therapy. Dose-volume histograms (DVHs) of the patients' thyroid gland were derived from their computed tomography (CT)-based treatment planning data. Hypothyroidism was defined as increased TSH (subclinical hypothyroidism) or increased TSH in combination with decreased free thyroxine and thyroxine (clinical hypothyroidism). Thyroid DVHs were converted to 2 Gy/fraction equivalent doses using the linear-quadratic formula with {alpha}/{beta} = 3 Gy. The evaluated models included the following: Lyman with the DVH reduced to the equivalent uniform dose (EUD), known as LEUD; Logit-EUD; mean dose; relative seriality; individual critical volume; and population critical volume models. The parameters of the models were obtained by fitting the patients' data using a maximum likelihood analysis method. The goodness of fit of the models was determined by the 2-sample Kolmogorov-Smirnov test. Ranking of the models was made according to Akaike's information criterion. Results: Twenty-nine patients (44.6%) experienced hypothyroidism. None of the models was rejected according to the evaluation of the goodness of fit. The mean dose model was ranked as the best model on the basis of its Akaike's information criterion value. The D{sub 50} estimated from the models was approximately 44 Gy. Conclusions: The implemented normal tissue complication probability models showed a parallel architecture for the thyroid. The mean dose model can be used as the best model to describe the dose-response relationship for hypothyroidism complication.

  10. Effect of non-standard interaction for radiative neutrino mass model

    SciTech Connect (OSTI)

    Konishi, Y.; Sato, J.; Shimomura, T. [Department of Physics, Saitama University, Shimo-okubo, Sakura-ku, Saitama, 338-8570 (Japan); Department of Physics, Niigata University, Niigata, 950-2181 (Japan)

    2012-07-27T23:59:59.000Z

    We examined effects of non-standard interactions (NSIs) in a radiative neutrino mass model. The radiative neutrino mass model suggested by Kraus Nasri and Trodden can explain not only neutrino flavor mixing and neutrino masses, but also dark matter relic abundance. Although the NSI effects of the model are too small to be detected by present neutrino oscillation experiments, we might observe the small effects in future experiments such as neutrino factory.

  11. Measured radiation patterns of the scale model dipole tool

    E-Print Network [OSTI]

    Lu, Rongrong

    2003-01-01T23:59:59.000Z

    The sound field of finite dipole acoustic transducers in a steel tool was investigated and their horizontal by measuring their vertical radiation patterns in water at two different frequencies. Measurements were also made ...

  12. SKIRT: the design of a suite of input models for Monte Carlo radiative transfer simulations

    E-Print Network [OSTI]

    Baes, Maarten

    2015-01-01T23:59:59.000Z

    The Monte Carlo method is the most popular technique to perform radiative transfer simulations in a general 3D geometry. The algorithms behind and acceleration techniques for Monte Carlo radiative transfer are discussed extensively in the literature, and many different Monte Carlo codes are publicly available. On the contrary, the design of a suite of components that can be used for the distribution of sources and sinks in radiative transfer codes has received very little attention. The availability of such models, with different degrees of complexity, has many benefits. For example, they can serve as toy models to test new physical ingredients, or as parameterised models for inverse radiative transfer fitting. For 3D Monte Carlo codes, this requires algorithms to efficiently generate random positions from 3D density distributions. We describe the design of a flexible suite of components for the Monte Carlo radiative transfer code SKIRT. The design is based on a combination of basic building blocks (which can...

  13. Monte Carlo Simulation of Radiation in Gases with a NarrowBand Model

    E-Print Network [OSTI]

    Dufresne, Jean-Louis

    , France (\\Phi) now at the Institute of Energy and Power Plant Technology, TH Darmstadt, 64287 DarmstadtMonte Carlo Simulation of Radiation in Gases with a Narrow­Band Model and a Net is used for simulation of radiative heat transfers in non­gray gases. The proposed procedure is based

  14. Modelling dynamics of samples exposed to free-electron-laser radiation with Boltzmann equations

    E-Print Network [OSTI]

    Beata Ziaja; Antonio R. B. de Castro; Edgar Weckert; Thomas Moeller

    2005-12-20T23:59:59.000Z

    We apply Boltzmann equations for modelling the radiation damage in samples irradiated by photons from free electron laser (FEL). We test this method in a study case of a spherically symmetric xenon cluster irradiated with VUV FEL photons. The results obtained demonstrate the potential of the Boltzmann method for describing the complex and non-equilibrium dynamics of samples exposed to FEL radiation.

  15. Optimizing spectral indices and chemometric analysis of leaf chemical properties using radiative transfer modeling

    E-Print Network [OSTI]

    Gitelson, Anatoly

    Optimizing spectral indices and chemometric analysis of leaf chemical properties using radiative for Sciences, 260 Panama Street, Stanford, CA 94305, USA d Center for Advanced Land Management Information squares regression We used synthetic reflectance spectra generated by a radiative transfer model, PROSPECT

  16. Optimizing spectral indices and chemometric analysis of leaf chemical properties using radiative transfer modeling

    E-Print Network [OSTI]

    Gitelson, Anatoly

    Optimizing spectral indices and chemometric analysis of leaf chemical properties using radiative for Sciences, 260 Panama Street, Stanford, CA 94305, USA d Center for Advanced Land Management Information regression We used synthetic reflectance spectra generated by a radiative transfer model, PROSPECT-5

  17. A Coupled Model for Radiative Transfer: Doppler Effects, Equilibrium and Non-Equilibrium Diffusion Asymptotics

    E-Print Network [OSTI]

    Goudon, Thierry

    A Coupled Model for Radiative Transfer: Doppler Effects, Equilibrium and Non-Equilibrium Diffusion. The interaction terms take into account both scattering and absorption/emission phenomena, as well as Doppler-diffusion equations. Key words. Hydrodynamic limits. Diffusion approximation. Radiative transfer. Doppler correction

  18. The Radiation Reaction Effects in the BMT Model of Spinning Charge and the Radiation Polarization Phenomenon

    E-Print Network [OSTI]

    S. L. Lebedev

    2005-12-19T23:59:59.000Z

    The effect of radiation polarization attended with the motion of spinning charge in the magnetic field could be viewed through the classical theory of self-interaction. The quantum expression for the polarization time follows from the semiclassical relation $T_{QED}\\sim \\hbar c^{3}/\\mu_{B}^2\\omega_{c}^3$, and needs quantum explanation neither for the orbit nor for the spin motion. In our approach the polarization emerges as a result of natural selection in the ensenmble of elastically scattered electrons among which the group of particles that bear their spins in the 'right' directions has the smaller probability of radiation. The evidence of non-complete polarization degree is also obtained.

  19. 2D radiative modelling of He I spectral lines formed in solar prominences

    E-Print Network [OSTI]

    L. Leger; F. Paletou

    2008-07-11T23:59:59.000Z

    We present preliminary results of 2D radiative modelling of He I lines in solar prominences, using a new numerical code developed by us (Leger, Chevallier and Paletou 2007). It treats self-consistently the radiation transfer and the non-LTE statistical equilibrium of H and, in a second stage, the one of He using a detailed atomic model. Preliminary comparisons with new visible plus near-infrared observations made at high spectral resolution with THeMIS are very satisfactory.

  20. Radiation transport modeling using extended quadrature method of moments

    SciTech Connect (OSTI)

    Vikas, V., E-mail: vvikas@iastate.edu [Department of Aerospace Engineering, 2271 Howe Hall, Iowa State University, Ames, IA 50011 (United States); Hauck, C.D., E-mail: hauckc@ornl.gov [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Wang, Z.J., E-mail: zjw@ku.edu [Department of Aerospace Engineering, 2120 Learned Hall, University of Kansas, Lawrence, KS 66045 (United States); Fox, R.O., E-mail: rofox@iastate.edu [Department of Chemical and Biological Engineering, 2114 Sweeney Hall, Iowa State University, Ames, IA 50011 (United States)

    2013-08-01T23:59:59.000Z

    The radiative transfer equation describes the propagation of radiation through a material medium. While it provides a highly accurate description of the radiation field, the large phase space on which the equation is defined makes it numerically challenging. As a consequence, significant effort has gone into the development of accurate approximation methods. Recently, an extended quadrature method of moments (EQMOM) has been developed to solve univariate population balance equations, which also have a large phase space and thus face similar computational challenges. The distinct advantage of the EQMOM approach over other moment methods is that it generates moment equations that are consistent with a positive phase space density and has a moment inversion algorithm that is fast and efficient. The goal of the current paper is to present the EQMOM method in the context of radiation transport, to discuss advantages and disadvantages, and to demonstrate its performance on a set of standard one-dimensional benchmark problems that encompass optically thin, thick, and transition regimes. Special attention is given in the implementation to the issue of realizability—that is, consistency with a positive phase space density. Numerical results in one dimension are promising and lay the foundation for extending the same framework to multiple dimensions.

  1. Methodology A simple linear model for radiative forcing of absorbing

    E-Print Network [OSTI]

    Peters, Karsten

    Absorbing aerosol in cloudy scenes: effects on atmospheric radia7on Aerosol Cloud Cloud prevents aerosol-radiation interaction; small negative forcing, i.e. COOLING Indirect rather than direct effect through modification of cloud properties Cloud enhances "surface albedo"; potentially large

  2. A physical model of radiated enhancement of plasma-surrounded antenna

    SciTech Connect (OSTI)

    Gao, Xiaotian; Wang, Chunsheng, E-mail: wangcs@hit.edu.cn; Jiang, Binhao; Zhang, Zhonglin [Harbin Institute of Technology, 92 West Dazhi Street, Nan Gang District, 150001 Harbin (China)

    2014-09-15T23:59:59.000Z

    A phenomenon that the radiated power may be enhanced when an antenna is surrounded by a finite plasma shell has been found in numerical and experimental studies. In this paper, a physical model was built to express the mechanism of the radiated enhancement. In this model, the plasma shell is treated as a parallel connection of a capacitance and a conductance whose parameters change with the system parameters (plasma density, collision frequency, and antenna frequency). So, the radiated enhancement can be explained by the resonance between the plasma shell and the infinite free space. Furthermore, the effects of system parameters on the radiated power are given and effects corresponding to mechanisms are performed based on the physical model.

  3. Viscous boundary layers of radiation-dominated, relativistic jets. II. The free-streaming jet model

    E-Print Network [OSTI]

    Coughlin, Eric R

    2015-01-01T23:59:59.000Z

    We analyze the interaction of a radiation-dominated jet and its surroundings using the equations of radiation hydrodynamics in the viscous limit. In a previous paper we considered the two-stream scenario, which treats the jet and its surroundings as distinct media interacting through radiation viscous forces. Here we present an alternative boundary layer model, known as the free-streaming jet model -- where a narrow stream of fluid is injected into a static medium -- and present solutions where the flow is ultrarelativistic and the boundary layer is dominated by radiation. It is shown that these jets entrain material from their surroundings and that their cores have a lower density of scatterers and a harder spectrum of photons, leading to observational consequences for lines of sight that look "down the barrel of the jet." These jetted outflow models may be applicable to the jets produced during long gamma-ray bursts and super-Eddington phases of tidal disruption events.

  4. Irreversible Processes in a Universe modelled as a mixture of a Chaplygin gas and radiation

    E-Print Network [OSTI]

    G. M. Kremer

    2003-03-26T23:59:59.000Z

    The evolution of a Universe modelled as a mixture of a Chaplygin gas and radiation is determined by taking into account irreversible processes. This mixture could interpolate periods of a radiation dominated, a matter dominated and a cosmological constant dominated Universe. The results of a Universe modelled by this mixture are compared with the results of a mixture whose constituents are radiation and quintessence. Among other results it is shown that: (a) for both models there exists a period of a past deceleration with a present acceleration; (b) the slope of the acceleration of the Universe modelled as a mixture of a Chaplygin gas with radiation is more pronounced than that modelled as a mixture of quintessence and radiation; (c) the energy density of the Chaplygin gas tends to a constant value at earlier times than the energy density of quintessence does; (d) the energy density of radiation for both mixtures coincide and decay more rapidly than the energy densities of the Chaplygin gas and of quintessence.

  5. A Prospective Cohort Study on Radiation-induced Hypothyroidism: Development of an NTCP Model

    SciTech Connect (OSTI)

    Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E.M.C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J.H.M. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Laan, Bernard F.A.M. van der [Department of Otorhinolaryngology/Head and Neck Surgery, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Wolffenbuttel, Bruce H.R. [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Oosting, Sjoukje F. [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Schilstra, Cornelis [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A., E-mail: j.a.langendijk@umcg.nl [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)

    2012-11-01T23:59:59.000Z

    Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism. Methods and Materials: The thyroid-stimulating hormone (TSH) level of 105 patients treated with (chemo-) radiation therapy for head-and-neck cancer was prospectively measured during a median follow-up of 2.5 years. Hypothyroidism was defined as elevated serum TSH with decreased or normal free thyroxin (T4). A multivariate logistic regression model with bootstrapping was used to determine the most important prognostic variables for radiation-induced hypothyroidism. Results: Thirty-five patients (33%) developed primary hypothyroidism within 2 years after radiation therapy. An NTCP model based on 2 variables, including the mean thyroid gland dose and the thyroid gland volume, was most predictive for radiation-induced hypothyroidism. NTCP values increased with higher mean thyroid gland dose (odds ratio [OR]: 1.064/Gy) and decreased with higher thyroid gland volume (OR: 0.826/cm{sup 3}). Model performance was good with an area under the curve (AUC) of 0.85. Conclusions: This is the first prospective study resulting in an NTCP model for radiation-induced hypothyroidism. The probability of hypothyroidism rises with increasing dose to the thyroid gland, whereas it reduces with increasing thyroid gland volume.

  6. Order Reduction of the Radiative Heat Transfer Model for the Simulation of Plasma Arcs

    E-Print Network [OSTI]

    Fagiano, Lorenzo

    2015-01-01T23:59:59.000Z

    An approach to derive low-complexity models describing thermal radiation for the sake of simulating the behavior of electric arcs in switchgear systems is presented. The idea is to approximate the (high dimensional) full-order equations, modeling the propagation of the radiated intensity in space, with a model of much lower dimension, whose parameters are identified by means of nonlinear system identification techniques. The low-order model preserves the main structural aspects of the full-order one, and its parameters can be straightforwardly used in arc simulation tools based on computational fluid dynamics. In particular, the model parameters can be used together with the common approaches to resolve radiation in magnetohydrodynamic simulations, including the discrete-ordinate method, the P-N methods and photohydrodynamics. The proposed order reduction approach is able to systematically compute the partitioning of the electromagnetic spectrum in frequency bands, and the related absorption coefficients, tha...

  7. Evaluation of GCM Column Radiation Models Under Cloudy Conditions with The Arm BBHRP Value Added Product

    SciTech Connect (OSTI)

    Dr. Lazaros Oreopoulos and Dr. Peter M. Norris

    2010-03-14T23:59:59.000Z

    The overarching goal of the project was to improve the transfer of solar and thermal radiation in the most sophisticated computer tools that are currently available for climate studies, namely Global Climate Models (GCMs). This transfer can be conceptually separated into propagation of radiation under cloudy and under cloudless conditions. For cloudless conditions, the factors that affect radiation propagation are gaseous absorption and scattering, aerosol particle absorption and scattering and surface albedo and emissivity. For cloudy atmospheres the factors are the various cloud properties such as cloud fraction, amount of cloud condensate, the size of the cloud particles, and morphological cloud features such as cloud vertical location, cloud horizontal and vertical inhomogeneity and cloud shape and size. The project addressed various aspects of the influence of the above contributors to atmospheric radiative transfer variability. In particular, it examined: (a) the quality of radiative transfer for cloudless and non-complex cloudy conditions for a substantial number of radiation algorithms used in current GCMs; (b) the errors in radiative fluxes from neglecting the horizontal variabiity of cloud extinction; (c) the statistical properties of cloud horizontal and vertical cloud inhomogeneity that can be incorporated into radiative transfer codes; (d) the potential albedo effects of changes in the particle size of liquid clouds; (e) the gaseous radiative forcing in the presence of clouds; and (f) the relative contribution of clouds of different sizes to the reflectance of a cloud field. To conduct the research in the various facets of the project, data from both the DOE ARM project and other sources were used. The outcomes of the project will have tangible effects on how the calculation of radiative energy will be approached in future editions of GCMs. With better calculations of radiative energy in GCMs more reliable predictions of future climate states will be attainable, thus affecting public policy decisions with great impact to public life.

  8. Macro-particle FEL model with self-consistent spontaneous radiation

    E-Print Network [OSTI]

    Litvinenko, Vladimir N

    2015-01-01T23:59:59.000Z

    Spontaneous radiation plays an important role in SASE FELs and storage ring FELs operating in giant pulse mode. It defines the correlation function of the FEL radiation as well as its many spectral features. Simulations of these systems using randomly distributed macro-particles with charge much higher that of a single electron create the problem of anomalously strong spontaneous radiation, limiting the capabilities of many FEL codes. In this paper we present a self-consistent macro-particle model which provided statistically exact simulation of multi-mode, multi-harmonic and multi-frequency short-wavelength 3-D FELs including the high power and saturation effects. The use of macro-particle clones allows both spontaneous and induced radiation to be treated in the same fashion. Simulations using this model do not require a seed and provide complete temporal and spatial structure of the FEL optical field.

  9. Radiative Reactions and Coherence Modeling in the High Altitude Electromagnetic Pulse

    E-Print Network [OSTI]

    Charles N. Vittitoe; Mario Rabinowitz

    2003-06-03T23:59:59.000Z

    A high altitude nuclear electromagnetic pulse (EMP) with a peak field intensity of 5 x 10^4 V/m carries momentum that results in a retarding force on the average Compton electron (radiating coherently to produce the waveform) with magnitude near that of the geomagnetic force responsible for the coherent radiation. The retarding force results from a self field effect. The Compton electron interaction with the self generated magnetic field due to the other electrons accounts for the momentum density in the propagating wave; interaction with the self generated electric field accounts for the energy flux density in the propagating wave. Coherent addition of radiation is also quantitatively modeled.

  10. Modeling of the radiation belt megnetosphere in decisional timeframes

    DOE Patents [OSTI]

    Koller, Josef; Reeves, Geoffrey D; Friedel, Reiner H.W.

    2013-04-23T23:59:59.000Z

    Systems and methods for calculating L* in the magnetosphere with essentially the same accuracy as with a physics based model at many times the speed by developing a surrogate trained to be a surrogate for the physics-based model. The trained model can then beneficially process input data falling within the training range of the surrogate model. The surrogate model can be a feedforward neural network and the physics-based model can be the TSK03 model. Operatively, the surrogate model can use parameters on which the physics-based model was based, and/or spatial data for the location where L* is to be calculated. Surrogate models should be provided for each of a plurality of pitch angles. Accordingly, a surrogate model having a closed drift shell can be used from the plurality of models. The feedforward neural network can have a plurality of input-layer units, there being at least one input-layer unit for each physics-based model parameter, a plurality of hidden layer units and at least one output unit for the value of L*.

  11. Quantum method of determination of penetrability in FRW model with radiation

    E-Print Network [OSTI]

    Sergei P. Maydanyuk

    2014-07-18T23:59:59.000Z

    In paper the closed Friedmann-Robertson-Walker model with quantization in presence of the positive cosmological constant, radiation and Chaplygin gas is studied. For analysis of tunneling probability for birth of an asymptotically deSitter, inflationary Universe as a function of the radiation energy a new definition of a "free" wave propagating inside strong fields is introduced. Vilenkin's tunneling boundary condition is corrected, penetrability and reflection are calculated in fully quantum stationary approach.

  12. The 1D Iterative Model for Predicting Thermal Radiation from a Jet Fire

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    manuscript, published in "6. International Seminar on Fire and Explosion Hazards (FEH), Leeds : UnitedThe 1D Iterative Model for Predicting Thermal Radiation from a Jet Fire Leroy, G.* and Duplantier of the current jet fire models used in the accidental fire risks department are semi- empirical. They depend

  13. The Radiative Properties of Small Clouds: Multi-Scale Observations and Modeling

    SciTech Connect (OSTI)

    Feingold, Graham [NOAA ESRL; McComiskey, Allison [CIRES, University of Colorado

    2013-09-25T23:59:59.000Z

    Warm, liquid clouds and their representation in climate models continue to represent one of the most significant unknowns in climate sensitivity and climate change. Our project combines ARM observations, LES modeling, and satellite imagery to characterize shallow clouds and the role of aerosol in modifying their radiative effects.

  14. A convective-radiative heat transfer model for gas core reactors

    SciTech Connect (OSTI)

    Chen, G.; Anghaie, S. [Univ. of Florida, Gainesville, FL (United States)

    1995-12-31T23:59:59.000Z

    A convective-radiative heat transfer model is developed and used to predict the temperature distribution in gaseous fuel nuclear reactor cores. The axisymmetric, thin layer Navier-Stokes equations with diffusive radiation source term are the basis for this modeling approach. An algebraic turbulence model is used to calculate the eddy viscosity. The Rosseland diffusion approximation is used to model the radiative heat transfer. A hybrid implicit-explicit numerical scheme with Gauss-Seidel iterative process and a highly stretched grid system near wall is employed to solve the governing equations. Several cases with different internal heat generation rates are modeled and analyzed. Results of the temperature distribution, wall heat flux and the associated Nusselt number are presented. The influence of the internal heat generation rate and the wall temperature on the radiative and convective wall heat fluxes are discussed. At gas and wall temperatures close to 3,500 K and 1,600 K, respectively, the radiative and convective heat transfer rates have similar values.

  15. analytical radiation model: Topics by E-print Network

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

    337 Coupled thermodynamic-dynamic semi-analytical model of Free Piston Stirling engines CERN Preprints Summary: The study of free piston Stirling engine (FPSE) requires both...

  16. THE DEVELOPMENT OF RADIATION EMBRITTLEMENT MODELS FOR U.S. POWER REACTOR PRESSURE VESSEL STEELS

    SciTech Connect (OSTI)

    Wang, Jy-An John [ORNL; Rao, Nageswara S [ORNL

    2006-01-01T23:59:59.000Z

    The information fusion technique is used to develop radiation embrittlement prediction models for reactor pressure vessel (RPV) steels from U.S. power reactors, including boiling water reactors and pressurized water reactors. The Charpy transition temperature-shift data is used as the primary index of RPV radiation embrittlement in this study. Six parameters {Cu, Ni, P, neutron fluence, irradiation time, and irradiation temperature {are used in the embrittlement prediction models. The results indicate that this new embrittlement predictor achieved reductions of about 49.5% and 52% in the uncertainties for plate and weld data, respectively, for pressurized water reactor and boiling water reactor data, compared with the Nuclear Regulatory Commission Regulatory Guide 1.99, Rev. 2. The implications of dose-rate effect and irradiation temperature effects for the development of radiation embrittlement models are also discussed.

  17. RAMI4PILPS: An intercomparison of formulations for the partitioning of solar radiation in land surface models

    E-Print Network [OSTI]

    Ni-Meister, Wenge

    RAMI4PILPS: An intercomparison of formulations for the partitioning of solar radiation in land for the partitioning of solar radiation in land surface models, J. Geophys. Res., 116, G02019, doi:10.1029/2010JG001511 [e.g., Zeng et al., 2000; Dai et al., 2004]. The partitioning of solar radiation between

  18. New formulae to evaluate the atmospheric layers of precipitable water and gases, applicable in solar radiation computing models

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    in solar radiation computing models V. B0103descu Energetica, Centrale Electrice, Polytechn. Inst irradiance. In this context, the relatively low density of solar radiation recording stations favoured measurements. Reviews and classifications of the main calculations procedures of solar radiation have been

  19. Evaluation of Clouds and Their Radiative Effects Simulated by the NCAR Community Atmospheric Model CAM2 Against Satellite Observations

    E-Print Network [OSTI]

    Bretherton, Chris

    Evaluation of Clouds and Their Radiative Effects Simulated by the NCAR Community Atmospheric Model-4738 (Accepted) #12;1 ABSTRACT Cloud climatology and the cloud radiative forcing at the top cloud radiative forcing at the TOA at different latitudes. The differences of cloud vertical structures

  20. Radiative hydrodynamics in the highly super adiabatic layer of stellar evolution models

    E-Print Network [OSTI]

    F. J. Robinson; P. Demarque; S. Sofia; K. L. Chan; Y. -C. Kim; D. B. Guenther

    2000-11-02T23:59:59.000Z

    We present results of three dimensional simulations of the uppermost part of the sun, at 3 stages of its evolution. Each model includes physically realistic radiative-hydrodynamics (the Eddington approximation is used in the optically thin region), varying opacities and a realistic equation of state (full treatment of the ionization of H and He). In each evolution model, we investigate a domain, which starts at the top of the photosphere and ends just inside the convection zone (about 2400 km in the sun model). This includes all of the super-adiabatic layer (SAL). Due to the different positions of the three models in the $log (g) $ vs $log T_{eff}$ plane, the more evolved models have lower density atmospheres. The reduction in density causes the amount of overshoot into the radiation layer, to be greater in the more evolved models.

  1. Single-Column Modeling, GCM Parameterizations and Atmospheric Radiation Measurement Data

    SciTech Connect (OSTI)

    Somerville, R.C.J.; Iacobellis, S.F.

    2005-03-18T23:59:59.000Z

    Our overall goal is identical to that of the Atmospheric Radiation Measurement (ARM) Program: the development of new and improved parameterizations of cloud-radiation effects and related processes, using ARM data at all three ARM sites, and the implementation and testing of these parameterizations in global and regional models. To test recently developed prognostic parameterizations based on detailed cloud microphysics, we have first compared single-column model (SCM) output with ARM observations at the Southern Great Plains (SGP), North Slope of Alaska (NSA) and Topical Western Pacific (TWP) sites. We focus on the predicted cloud amounts and on a suite of radiative quantities strongly dependent on clouds, such as downwelling surface shortwave radiation. Our results demonstrate the superiority of parameterizations based on comprehensive treatments of cloud microphysics and cloud-radiative interactions. At the SGP and NSA sites, the SCM results simulate the ARM measurements well and are demonstrably more realistic than typical parameterizations found in conventional operational forecasting models. At the TWP site, the model performance depends strongly on details of the scheme, and the results of our diagnostic tests suggest ways to develop improved parameterizations better suited to simulating cloud-radiation interactions in the tropics generally. These advances have made it possible to take the next step and build on this progress, by incorporating our parameterization schemes in state-of-the-art 3D atmospheric models, and diagnosing and evaluating the results using independent data. Because the improved cloud-radiation results have been obtained largely via implementing detailed and physically comprehensive cloud microphysics, we anticipate that improved predictions of hydrologic cycle components, and hence of precipitation, may also be achievable. We are currently testing the performance of our ARM-based parameterizations in state-of-the--art global and regional models. One fruitful strategy for evaluating advances in parameterizations has turned out to be using short-range numerical weather prediction as a test-bed within which to implement and improve parameterizations for modeling and predicting climate variability. The global models we have used to date are the CAM atmospheric component of the National Center for Atmospheric Research (NCAR) CCSM climate model as well as the National Centers for Environmental Prediction (NCEP) numerical weather prediction model, thus allowing testing in both climate simulation and numerical weather prediction modes. We present detailed results of these tests, demonstrating the sensitivity of model performance to changes in parameterizations.

  2. Broadband Model Performance for an Updated National Solar Radiation Database in the United States of America: Preprint

    SciTech Connect (OSTI)

    Myers, D. R.; Wilcox, S.; Marion, W.; George, R.; Anderberg, M.

    2005-09-01T23:59:59.000Z

    Updated review of broadband model performance in a project being done to update the existing United States National Solar Radiation Database (NSRDB).

  3. Effective-medium model of wire metamaterials in the problems of radiative heat transfer

    SciTech Connect (OSTI)

    Mirmoosa, M. S., E-mail: mohammad.mirmoosa@aalto.fi; Nefedov, I. S., E-mail: igor.nefedov@aalto.fi; Simovski, C. R., E-mail: konstantin.simovski@aalto.fi [Department of Radio Science and Engineering, School of Electrical Engineering, Aalto University, P. O. Box 13000, 00076 Aalto (Finland); Rüting, F., E-mail: felix.ruting@uam.es [Departamento de Física Teorica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autonoma de Madrid, E-28049 (Spain)

    2014-06-21T23:59:59.000Z

    In the present work, we check the applicability of the effective medium model (EMM) to the problems of radiative heat transfer (RHT) through so-called wire metamaterials (WMMs)—composites comprising parallel arrays of metal nanowires. It is explained why this problem is so important for the development of prospective thermophotovoltaic (TPV) systems. Previous studies of the applicability of EMM for WMMs were targeted by the imaging applications of WMMs. The analogous study referring to the transfer of radiative heat is a separate problem that deserves extended investigations. We show that WMMs with practically realizable design parameters transmit the radiative heat as effectively homogeneous media. Existing EMM is an adequate tool for qualitative prediction of the magnitude of transferred radiative heat and of its effective frequency band.

  4. Modeling progression in radiation-induced lung adenocarcinomas

    E-Print Network [OSTI]

    Fakir, Hatim; Hofmann, Werner; Sachs, Rainer K.

    2010-01-01T23:59:59.000Z

    carrying capacity. Indeed, Speer et al. (1984) showed thatdata for tumor growth (Speer et al. 1984). In our study,model. Math Biosci Speer JF, Petrosky VE, Retsky MW,

  5. The Los Alamos dynamic radiation environment assimilation model (DREAM) for space weather specification and forecasting

    SciTech Connect (OSTI)

    Reeves, Geoffrey D [Los Alamos National Laboratory; Friedel, Reiner H W [Los Alamos National Laboratory; Chen, Yue [Los Alamos National Laboratory; Koller, Josef [Los Alamos National Laboratory; Henderson, Michael G [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    The Dynamic Radiation Environment Assimilation Model (DREAM) was developed at Los Alamos National Laboratory to assess, quantify, and predict the hazards from the natural space environment and the anthropogenic environment produced by high altitude nuclear explosions (HANE). DREAM was initially developed as a basic research activity to understand and predict the dynamics of the Earth's Van Allen radiation belts. It uses Kalman filter techniques to assimilate data from space environment instruments with a physics-based model of the radiation belts. DREAM can assimilate data from a variety of types of instruments and data with various levels of resolution and fidelity by assigning appropriate uncertainties to the observations. Data from any spacecraft orbit can be assimilated but DREAM was designed to function with as few as two spacecraft inputs: one from geosynchronous orbit and one from GPS orbit. With those inputs, DREAM can be used to predict the environment at any satellite in any orbit whether space environment data are available in those orbits or not. Even with very limited data input and relatively simple physics models, DREAM specifies the space environment in the radiation belts to a high level of accuracy. DREAM has been extensively tested and evaluated as we transition from research to operations. We report here on one set of test results in which we predict the environment in a highly-elliptical polar orbit. We also discuss long-duration reanalysis for spacecraft design, using DREAM for real-time operations, and prospects for 1-week forecasts of the radiation belt environment.

  6. The Accretion Wind Model of the Fermi Bubbles (II): Radiation

    E-Print Network [OSTI]

    Mou, Guobin; Gan, Zhaoming; Sun, Mouyuan

    2015-01-01T23:59:59.000Z

    In a previous work, we have shown that the formation of the Fermi bubbles can be due to the interaction between winds launched from the hot accretion flow in Sgr A* and the interstellar medium (ISM). In that work, we focus only on the morphology. In this paper we continue our study by calculating the gamma-ray radiation. Some cosmic ray protons (CRp) and electrons must be contained in the winds, which are likely formed by physical processes such as magnetic reconnection. We have performed MHD simulations to study the spatial distribution of CRp, considering the advection and diffusion of CRp in the presence of magnetic field. We find that a permeated zone is formed just outside of the contact discontinuity between winds and ISM, where the collisions between CRp and thermal nuclei mainly occur. The decay of neutral pions generated in the collisions, combined with the inverse Compton scattering of background soft photons by the secondary leptons generated in the collisions and primary CR electrons can well expl...

  7. A parametric study of shock jump chemistry, electron temperature, and radiative heat transfer models in hypersonic flows 

    E-Print Network [OSTI]

    Greendyke, Robert Brian

    1988-01-01T23:59:59.000Z

    will examine the radiance model and various step models in order to determine their appropriateness to the flight regime of the AOTV. The final area to be investigated will be the effect of nonequilibrium corrections on the radiative heat transfer models... of T and e T will be valid as long as there is a reasonable amount vNs of nitrogen molecules in the flow. Radiative Heat Transfer Models For this study, four radiative heat transfer models were examined. One of these models is an optically thin radiance...

  8. Measurements and modeling of soot formation and radiation in microgravity jet diffusion flames

    SciTech Connect (OSTI)

    Ku, J.C.; Tong, L. [Wayne State Univ., Detroit, MI (United States). Mechanical Engineering Dept.; Greenberg, P.S. [NASA Lewis Research Center, Cleveland, OH (United States). Microgravity Combustion Branch

    1996-12-31T23:59:59.000Z

    This is a computational and experimental study for soot formation and radiative heat transfer in jet diffusion flames under normal gravity (1-g) and microgravity (0-g) conditions. Instantaneous soot volume fraction maps are measured using a full-field imaging absorption technique developed by the authors. On modeling, the authors have coupled flame structure and soot formation models with detailed radiation transfer calculations. Favre-averaged boundary layer equations with a k-e-g turbulence model are used to predict the flow field, and a conserved scalar approach with an assumed {beta}-pdf are used to predict gaseous species mole fraction. Scalar transport equations are used to describe soot volume fraction and number density distributions, with formation and oxidation terms modeled by one-step rate equations and thermophoretic effects included. An energy equation is included to couple flame structure and radiation analyses through iterations, neglecting turbulence-radiation interactions. The YIX solution for a finite cylindrical enclosure is used for radiative heat transfer calculations. The spectral absorption coefficient for soot aggregates is calculated from the Rayleigh solution using complex refractive index data from a Drude-Lorentz model. The exponential-wide-band model is used to calculate the spectral absorption coefficient for H{sub 2}O and CO{sub 2}. Predicted soot volume fraction and temperature results agree well with published data for a normal gravity co-flow laminar flames and turbulent jet flames. Predicted soot volume fraction results also agree with the data for 1-g and 0-g laminar jet flames as well as 1-g turbulent jet flames.

  9. Three-dimensional Radiative Transfer Modeling of the Polarization of the Sun's Continuous Spectrum

    E-Print Network [OSTI]

    J. Trujillo Bueno; N. Shchukina

    2008-12-18T23:59:59.000Z

    Here we formulate and solve the 3D radiative transfer problem of the polarization of the solar continuous radiation. Our approach takes into account not only the anisotropy of the continuum radiation, but also the symmetry-breaking effects caused by the horizontal atmospheric inhomogeneities produced by the solar surface convection. Interestingly, our radiative transfer modeling in a well-known 3D hydrodynamical model of the solar photosphere shows remarkable agreement with the empirical data, significantly better than that obtained via the use of 1D atmospheric models. Although this result confirms that the above-mentioned 3D model was indeed a suitable choice for our Hanle-effect estimation of the substantial amount of "hidden" magnetic energy that is stored in the quiet solar photosphere, we have found however some small discrepancies whose origin may be due to uncertainties in the empirical data and/or in the thermal and density structure of the 3D model. For this reason, we have paid some attention also to other (more familiar) observables, like the center-limb variation of the continuum intensity, which we have calculated taking into account the scattering contribution to the continuum source function. The overall agreement with the observed center-limb variation turns out to be impressive, but we find a hint that the model's temperature gradients in the continuum forming layers could be slightly too steep, perhaps because all current simulations of solar surface convection and magnetoconvection compute the radiative flux divergence ignoring the fact that the effective polarizability is not completely negligible, especially in the downward-moving intergranular lane plasma.

  10. A GENERAL CIRCULATION MODEL FOR GASEOUS EXOPLANETS WITH DOUBLE-GRAY RADIATIVE TRANSFER

    SciTech Connect (OSTI)

    Rauscher, Emily [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Boulevard, Tucson, AZ 85721-0092 (United States); Menou, Kristen [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)

    2012-05-10T23:59:59.000Z

    We present a new version of our code for modeling the atmospheric circulation on gaseous exoplanets, now employing a 'double-gray' radiative transfer scheme, which self-consistently solves for fluxes and heating throughout the atmosphere, including the emerging (observable) infrared flux. We separate the radiation into infrared and optical components, each with its own absorption coefficient, and solve standard two-stream radiative transfer equations. We use a constant optical absorption coefficient, while the infrared coefficient can scale as a power law with pressure; however, for simplicity, the results shown in this paper use a constant infrared coefficient. Here we describe our new code in detail and demonstrate its utility by presenting a generic hot Jupiter model. We discuss issues related to modeling the deepest pressures of the atmosphere and describe our use of the diffusion approximation for radiative fluxes at high optical depths. In addition, we present new models using a simple form for magnetic drag on the atmosphere. We calculate emitted thermal phase curves and find that our drag-free model has the brightest region of the atmosphere offset by {approx}12 Degree-Sign from the substellar point and a minimum flux that is 17% of the maximum, while the model with the strongest magnetic drag has an offset of only {approx}2 Degree-Sign and a ratio of 13%. Finally, we calculate rates of numerical loss of kinetic energy at {approx}15% for every model except for our strong-drag model, where there is no measurable loss; we speculate that this is due to the much decreased wind speeds in that model.

  11. A stochastic model for tumor geometry evolution during radiation therapy in cervical cancer

    SciTech Connect (OSTI)

    Liu, Yifang; Lee, Chi-Guhn [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario M5S 3G8 (Canada)] [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario M5S 3G8 (Canada); Chan, Timothy C. Y., E-mail: tcychan@mie.utoronto.ca [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario M5S 3G8, Canada and Techna Institute for the Advancement of Technology for Health, 124-100 College Street Toronto, Ontario M5G 1P5 (Canada)] [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario M5S 3G8, Canada and Techna Institute for the Advancement of Technology for Health, 124-100 College Street Toronto, Ontario M5G 1P5 (Canada); Cho, Young-Bin [Department of Radiation Physics, Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, 610 University of Avenue, Toronto, Ontario M5T 2M9, Canada and Department of Radiation Oncology, University of Toronto, 148-150 College Street, Toronto, Ontario M5S 3S2 (Canada)] [Department of Radiation Physics, Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, 610 University of Avenue, Toronto, Ontario M5T 2M9, Canada and Department of Radiation Oncology, University of Toronto, 148-150 College Street, Toronto, Ontario M5S 3S2 (Canada); Islam, Mohammad K. [Department of Radiation Physics, Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, 610 University of Avenue, Toronto, Ontario M5T 2M9 (Canada) [Department of Radiation Physics, Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, 610 University of Avenue, Toronto, Ontario M5T 2M9 (Canada); Department of Radiation Oncology, University of Toronto, 148-150 College Street, Toronto, Ontario M5S 3S2 (Canada); Techna Institute for the Advancement of Technology for Health, 124-100 College Street, Toronto, Ontario M5G 1P5 (Canada)

    2014-02-15T23:59:59.000Z

    Purpose: To develop mathematical models to predict the evolution of tumor geometry in cervical cancer undergoing radiation therapy. Methods: The authors develop two mathematical models to estimate tumor geometry change: a Markov model and an isomorphic shrinkage model. The Markov model describes tumor evolution by investigating the change in state (either tumor or nontumor) of voxels on the tumor surface. It assumes that the evolution follows a Markov process. Transition probabilities are obtained using maximum likelihood estimation and depend on the states of neighboring voxels. The isomorphic shrinkage model describes tumor shrinkage or growth in terms of layers of voxels on the tumor surface, instead of modeling individual voxels. The two proposed models were applied to data from 29 cervical cancer patients treated at Princess Margaret Cancer Centre and then compared to a constant volume approach. Model performance was measured using sensitivity and specificity. Results: The Markov model outperformed both the isomorphic shrinkage and constant volume models in terms of the trade-off between sensitivity (target coverage) and specificity (normal tissue sparing). Generally, the Markov model achieved a few percentage points in improvement in either sensitivity or specificity compared to the other models. The isomorphic shrinkage model was comparable to the Markov approach under certain parameter settings. Convex tumor shapes were easier to predict. Conclusions: By modeling tumor geometry change at the voxel level using a probabilistic model, improvements in target coverage and normal tissue sparing are possible. Our Markov model is flexible and has tunable parameters to adjust model performance to meet a range of criteria. Such a model may support the development of an adaptive paradigm for radiation therapy of cervical cancer.

  12. BTRAM: An Interactive Atmospheric Radiative Transfer Model I.M. Chapman1

    E-Print Network [OSTI]

    Naylor, David A.

    radiance incident on the spectrometer/radiometer. Computer simulations, known as radiative transfer models source of opacity at submillimetre wavelengths where many objects emit most of their energy. Although high altitude observatories (such as the James Clerk Maxwell Telescope (JCMT) in Hawaii and the Atacama

  13. CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL

    E-Print Network [OSTI]

    Heinemann, Detlev

    CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL Enio B-970, SP, Brazil. Phone + 55 12 39456741, Fax + 55 12 39456810, fernando@dge.inpe.br. Samuel L. Abreu, Hans, Federal University of Santa Catarina -UFSC, Florianópolis, 88040-900, (SC), Brazil. Richard Perez

  14. Radiative Models of Sagittarius A* and M87 from Relativistic MHD Simulations

    E-Print Network [OSTI]

    Militzer, Burkhard

    Radiative Models of Sagittarius A* and M87 from Relativistic MHD Simulations Jason Dexter of this dissertation may be referred to Proquest Information and Learning, 300 North Zeeb Road, Ann Arbor, MI 48106 Simulations Jason Dexter Chair of the Supervisory Committee: Professor Eric Agol Department of Astronomy

  15. Thoughts on entropic gravity in the Parikh-Wilczek tunneling model of Hawking radiation

    E-Print Network [OSTI]

    Wen-Yu Wen

    2014-05-28T23:59:59.000Z

    In this letter, we use the Parikh-Wilczek tunneling model of Hawking radiation to illustrate that a reformulation of Verlinde's entropic gravity is needed to derive the Newton's law for a temperature-varying screen, demanded by the conservation of energy. Furthermore, the entropy stored in the holographic screen is shown to be additive and its temperature dependence can be obtained.

  16. INVENTORY OF SOLAR RADIATION/SOLAR ENERGY SYSTEMS ESTIMATORS, MODELS, SITE-SPECIFIC DATA, AND PUBLICATIONS

    E-Print Network [OSTI]

    INVENTORY OF SOLAR RADIATION/SOLAR ENERGY SYSTEMS ESTIMATORS, MODELS, SITE-SPECIFIC DATA, and Buildings Systems Integration Center National Renewable Energy Laboratory 8 July 2009 SOLAR SYSTEM POTENTIAL/calculators/PVWATTS/version1/ http://rredc.nrel.gov/solar/calculators/PVWATTS/version2/ Estimates the electrical energy

  17. Combined Treatment Effects of Radiation and Immunotherapy: Studies in an Autochthonous Prostate Cancer Model

    SciTech Connect (OSTI)

    Wada, Satoshi [Department of Oncology, James Buchanan Brady Urological Institute, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Harris, Timothy J.; Tryggestad, Erik [Department of Radiation Oncology and Molecular Radiation Sciences, James Buchanan Brady Urological Institute, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Yoshimura, Kiyoshi [Department of Oncology, James Buchanan Brady Urological Institute, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Zeng, Jing [Department of Radiation Oncology and Molecular Radiation Sciences, James Buchanan Brady Urological Institute, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Yen, Hung-Rong; Getnet, Derese; Grosso, Joseph F.; Bruno, Tullia C. [Department of Oncology, James Buchanan Brady Urological Institute, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); De Marzo, Angelo M. [Department of Pathology, James Buchanan Brady Urological Institute, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Department of Urology, James Buchanan Brady Urological Institute, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); and others

    2013-11-15T23:59:59.000Z

    Purpose: To optimize the combination of ionizing radiation and cellular immunotherapy using a preclinical autochthonous model of prostate cancer. Methods and Materials: Transgenic mice expressing a model antigen under a prostate-specific promoter were treated using a platform that integrates cone-beam CT imaging with 3-dimensional conformal therapy. Using this technology we investigated the immunologic and therapeutic effects of combining ionizing radiation with granulocyte/macrophage colony-stimulating factor-secreting cellular immunotherapy for prostate cancer in mice bearing autochthonous prostate tumors. Results: The combination of ionizing radiation and immunotherapy resulted in a significant decrease in pathologic tumor grade and gross tumor bulk that was not evident with either single-modality therapy. Furthermore, combinatorial therapy resulted in improved overall survival in a preventive metastasis model and in the setting of established micrometastases. Mechanistically, combined therapy resulted in an increase of the ratio of effector-to-regulatory T cells for both CD4 and CD8 tumor-infiltrating lymphocytes. Conclusions: Our preclinical model establishes a potential role for the use of combined radiation-immunotherapy in locally advanced prostate cancer, which warrants further exploration in a clinical setting.

  18. Modeling proton intensity gradients and radiation dose equivalents in the inner

    E-Print Network [OSTI]

    Pringle, James "Jamie"

    Modeling proton intensity gradients and radiation dose equivalents in the inner heliosphere using exposure in IP space. In this paper, we utilize EMMREM to study the radial dependence of proton peak crossfield diffusion at large radial distances. Our results show that radial dependencies of proton peak

  19. MODELLING RADIATIVELY ACTIVE WATER-ICE CLOUDS: IMPACT ON THE THERMAL STRUCTURE AND WATER CYCLE.

    E-Print Network [OSTI]

    Madeleine, Jean-Baptiste

    MODELLING RADIATIVELY ACTIVE WATER-ICE CLOUDS: IMPACT ON THE THERMAL STRUCTURE AND WATER CYCLE. J. The essential role of water-ice clouds in shaping the thermal structure of the martian atmosphere has been long presumed [1] but neglected in GCMs because of the lack of observations and difficulty to predict

  20. Testing Radiative Neutrino Mass Models at the LHC

    E-Print Network [OSTI]

    Yi Cai; Jackson D. Clarke; Michael A. Schmidt; Raymond R. Volkas

    2015-02-07T23:59:59.000Z

    The Large Hadron Collider provides us new opportunities to search for the origin of neutrino mass. Beyond the minimal see-saw models a plethora of models exist which realise neutrino mass at tree- or loop-level, and it is important to be sure that these possibilities are satisfactorily covered by searches. The purpose of this paper is to advance a systematic approach to this problem. Majorana neutrino mass models can be organised by SM-gauge-invariant operators which violate lepton number by two units. In this paper we write down the minimal ultraviolet completions for all of the mass-dimension 7 operators. We predict vector-like quarks, vector-like leptons, scalar leptoquarks, a charged scalar, and a scalar doublet, whose properties are constrained by neutrino oscillation data. A detailed collider study is presented for $O_3=LLQ\\bar dH$ and $O_8 = L\\bar d\\bar e^\\dagger \\bar u^\\dagger H$ completions with a vector-like quark $\\chi\\sim(3, 2, -\\frac{5}{6})$ and a leptoquark $\\phi\\sim(\\bar 3,1,\\frac{1}{3})$. The existing LHC limits extracted from searches for vector-like fermions and sbottoms/stops are $m_\\chi \\gtrsim 620$ GeV and $m_\\phi\\gtrsim 600$ GeV.

  1. A Statistical Model for Generating a Population of Unclassified Objects and Radiation Signatures Spanning Nuclear Threats

    SciTech Connect (OSTI)

    Nelson, K; Sokkappa, P

    2008-10-29T23:59:59.000Z

    This report describes an approach for generating a simulated population of plausible nuclear threat radiation signatures spanning a range of variability that could be encountered by radiation detection systems. In this approach, we develop a statistical model for generating random instances of smuggled nuclear material. The model is based on physics principles and bounding cases rather than on intelligence information or actual threat device designs. For this initial stage of work, we focus on random models using fissile material and do not address scenarios using non-fissile materials. The model has several uses. It may be used as a component in a radiation detection system performance simulation to generate threat samples for injection studies. It may also be used to generate a threat population to be used for training classification algorithms. In addition, we intend to use this model to generate an unclassified 'benchmark' threat population that can be openly shared with other organizations, including vendors, for use in radiation detection systems performance studies and algorithm development and evaluation activities. We assume that a quantity of fissile material is being smuggled into the country for final assembly and that shielding may have been placed around the fissile material. In terms of radiation signature, a nuclear weapon is basically a quantity of fissile material surrounded by various layers of shielding. Thus, our model of smuggled material is expected to span the space of potential nuclear weapon signatures as well. For computational efficiency, we use a generic 1-dimensional spherical model consisting of a fissile material core surrounded by various layers of shielding. The shielding layers and their configuration are defined such that the model can represent the potential range of attenuation and scattering that might occur. The materials in each layer and the associated parameters are selected from probability distributions that span the range of possibilities. Once an object is generated, its radiation signature is calculated using a 1-dimensional deterministic transport code. Objects that do not make sense based on physics principles or other constraints are rejected. Thus, the model can be used to generate a population of spectral signatures that spans a large space, including smuggled nuclear material and nuclear weapons.

  2. Simulation and modeling for the stand-off radiation detection system (SORDS) using GEANT4

    SciTech Connect (OSTI)

    Hoover, Andrew S [Los Alamos National Laboratory; Wallace, Mark [Los Alamos National Laboratory; Galassi, Mark [Los Alamos National Laboratory; Mocko, Michal [Los Alamos National Laboratory; Palmer, David [Los Alamos National Laboratory; Schultz, Larry [Los Alamos National Laboratory; Tornga, Shawn [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    A Stand-Off Radiation Detection System (SORDS) is being developed through a joint effort by Raytheon, Los Alamos National Laboratory, Bubble Technology Industries, Radiation Monitoring Devices, and the Massachusetts Institute of Technology, for the Domestic Nuclear Detection Office (DNDO). The system is a mobile truck-based platform performing detection, imaging, and spectroscopic identification of gamma-ray sources. A Tri-Modal Imaging (TMI) approach combines active-mask coded aperture imaging, Compton imaging, and shadow imaging techniques. Monte Carlo simulation and modeling using the GEANT4 toolkit was used to generate realistic data for the development of imaging algorithms and associated software code.

  3. Radiative reactions and coherence modeling in the high-altitude electromagnetic pulse

    SciTech Connect (OSTI)

    Vittitoe, C.N.; Rabinowitz, M.

    1988-03-15T23:59:59.000Z

    A high-altitude nuclear electromagnetic pulse (EMP) with a peak field intensity of 5 x 10/sup 4/ V/m carries momentum that results in a retarding force on the average Compton electron (radiating coherently to produce the waveform) with magnitude near that of the geomagnetic force responsible for the coherent radiation. The retarding force results from a self-field effect. The Compton electron interaction with the self-generated magnetic field due to the other electrons accounts for the momentum density in the propagating wave; interaction with the self-generated electric field accounts for the energy-flux density in the propagating wave. Coherent addition of radiation is also quantitatively modeled.

  4. A unified model for radiation-resistance of advanced space solar cells

    SciTech Connect (OSTI)

    Yamaguchi, Masafumi [Toyota Technical Inst., Nagoya (Japan); Katsumoto, Shingo [Univ. of Tokyo (Japan); Amano, Chikara [NTT Opto-Electrical Labs., Kanagawa (Japan)

    1994-12-31T23:59:59.000Z

    1-MeV electron irradiation effects on MBE-grown InGaAs and AlGaAs solar cells have been examined in comparison with previous results for radiation damage of InP and GaAs solar cells in order to clarify radiation-resistance of advanced space solar cells. Moreover, 1-MeV electron irradiation results of several space solar cells such as InP, InGaP, InGaAsP, GaAs, AlGaAs, InGaAs, Si, Ge, and CuInSe{sub 2} cells have also been analyzed by considering their damage constants, bandgap energies and optical absorption coefficients. The authors believe that this study will provide a unified model for radiation-resistance of advanced space solar cells.

  5. Automotive Underhood Thermal Management Analysis Using 3-D Coupled Thermal-Hydrodynamic Computer Models: Thermal Radiation Modeling

    SciTech Connect (OSTI)

    Pannala, S; D'Azevedo, E; Zacharia, T

    2002-02-26T23:59:59.000Z

    The goal of the radiation modeling effort was to develop and implement a radiation algorithm that is fast and accurate for the underhood environment. As part of this CRADA, a net-radiation model was chosen to simulate radiative heat transfer in an underhood of a car. The assumptions (diffuse-gray and uniform radiative properties in each element) reduce the problem tremendously and all the view factors for radiation thermal calculations can be calculated once and for all at the beginning of the simulation. The cost for online integration of heat exchanges due to radiation is found to be less than 15% of the baseline CHAD code and thus very manageable. The off-line view factor calculation is constructed to be very modular and has been completely integrated to read CHAD grid files and the output from this code can be read into the latest version of CHAD. Further integration has to be performed to accomplish the same with STAR-CD. The main outcome of this effort is to obtain a highly scalable and portable simulation capability to model view factors for underhood environment (for e.g. a view factor calculation which took 14 hours on a single processor only took 14 minutes on 64 processors). The code has also been validated using a simple test case where analytical solutions are available. This simulation capability gives underhood designers in the automotive companies the ability to account for thermal radiation - which usually is critical in the underhood environment and also turns out to be one of the most computationally expensive components of underhood simulations. This report starts off with the original work plan as elucidated in the proposal in section B. This is followed by Technical work plan to accomplish the goals of the project in section C. In section D, background to the current work is provided with references to the previous efforts this project leverages on. The results are discussed in section 1E. This report ends with conclusions and future scope of work in section F.

  6. A problem of hypothetical emerging of cosmic background radiation photons on horizon in the standard model of universe

    E-Print Network [OSTI]

    V. Skalsky

    2000-09-25T23:59:59.000Z

    The present temperature of cosmic background radiation and the present number density of photons of cosmic background radiation in the observed expansive and isotropic relativistic Universe is in the standard model of universe explained by the assumption of emergence of the photons of cosmic background radiation on the horizon (of the most remote visibility). However, the physical analysis shows unambiguously that this assumption contradicts the special theory of relativity and the quantum mechanics.

  7. Viscous boundary layers of radiation-dominated, relativistic jets. I. The two-stream model

    E-Print Network [OSTI]

    Coughlin, Eric R

    2015-01-01T23:59:59.000Z

    Using the relativistic equations of radiation hydrodynamics in the viscous limit, we analyze the boundary layers that develop between radiation-dominated jets and their environments. In this paper we present the solution for the self-similar, 2-D, plane-parallel two-stream problem, wherein the jet and the ambient medium are considered to be separate, interacting fluids, and we compare our results to those of previous authors. (In a companion paper we investigate an alternative scenario, known as the free-streaming jet model.) Consistent with past findings, we show that the boundary layer that develops between the jet and its surroundings creates a region of low-density material. These models may be applicable to sources such as super-Eddington tidal disruption events and long gamma-ray bursts.

  8. Modeling dust as component minerals in the Community Atmosphere Model: development of framework and impact on radiative forcing

    SciTech Connect (OSTI)

    Scanza, Rachel; Mahowald, N.; Ghan, Steven J.; Zender, C. S.; Kok, J. F.; Liu, Xiaohong; Zhang, Y.; Albani, Samuel

    2015-01-01T23:59:59.000Z

    The mineralogy of desert dust is important due to its effect on radiation, clouds and biogeochemical cycling of trace nutrients. This study presents the simulation of dust radiative forcing as a function of both mineral composition and size at the global scale using mineral soil maps for estimating emissions. Externally mixed mineral aerosols in the bulk aerosol module in the Community Atmosphere Model version 4 (CAM4) and internally mixed mineral aerosols in the modal aerosol module in the Community Atmosphere Model version 5.1 (CAM5) embedded in the Community Earth System Model version 1.0.5 (CESM) are speciated into common mineral components in place of total dust. The simulations with mineralogy are compared to available observations of mineral atmospheric distribution and deposition along with observations of clear-sky radiative forcing efficiency. Based on these simulations, we estimate the all-sky direct radiative forcing at the top of the atmosphere as +0.05Wm?2 for both CAM4 and CAM5 simulations with mineralogy and compare this both with simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17Wm?2) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, ?0.05 and ?0.17Wm?2, respectively. The ability to correctly include the mineralogy of dust in climate models is hindered by its spatial and temporal variability as well as insufficient global in-situ observations, incomplete and uncertain source mineralogies and the uncertainties associated with data retrieved from remote sensing methods.

  9. The dusty MOCASSIN: fully self-consistent 3D photoionisation and dust radiative transfer models

    E-Print Network [OSTI]

    B. Ercolano; M. J. Barlow; P. J. Storey

    2005-07-02T23:59:59.000Z

    We present the first 3D Monte Carlo (MC) photoionisation code to include a fully self-consistent treatment of dust radiative transfer (RT) within a photoionised region. This is the latest development (Version 2.0) of the gas-only photoionisation code MOCASSIN (Ercolano et al., 2003a), and employs a stochastic approach to the transport of radiation, allowing both the primary and secondary components of the radiation field to be treated self-consistently, whilst accounting for the scattering of radiation by dust grains mixed with the gas, as well as the absorption and emission of radiation by both the gas and the dust components. A set of rigorous benchmark tests have been carried out for dust-only spherically symmetric geometries and 2D disk configurations. MOCASSIN's results are found to be in agreement with those obtained by well established dust-only RT codes that employ various approaches to the solution of the RT problem. A model of the dust and of the photoionised gas components of the planetary nebula (PN) NGC 3918 is also presented as a means of testing the correct functioning of the RT procedures in a case where both gas and dust opacities are present. The two components are coupled via the heating of dust grains by the absorption of both UV continuum photons and resonance line photons emitted by the gas. The MOCASSIN results show agreement with those of a 1D dust and gas model of this nebula published previously, showing the reliability of the new code, which can be applied to a variety of astrophysical environments.

  10. Studies Of Coherent Synchrotron Radiation And Longitudinal Space Charge In The Jefferson Lab FEL Driver

    SciTech Connect (OSTI)

    Tennant, Christopher D. [JLAB; Douglas, David R. [JLAB; Li, Rui [JLAB; Tsai, C.-Y. [Virginia Polytechnic University

    2014-12-01T23:59:59.000Z

    The Jefferson Laboratory IR FEL Driver provides an ideal test bed for studying a variety of beam dynamical effects. Recent studies focused on characterizing the impact of coherent synchrotron radiation (CSR) with the goal of benchmarking measurements with simulation. Following measurements to characterize the beam, we quantitatively characterized energy extraction via CSR by measuring beam position at a dispersed location as a function of bunch compression. In addition to operating with the beam on the rising part of the linac RF waveform, measurements were also made while accelerating on the falling part. For each, the full compression point was moved along the backleg of the machine and the response of the beam (distribution, extracted energy) measured. Initial results of start-to-end simulations using a 1D CSR algorithm show remarkably good agreement with measurements. A subsequent experiment established lasing with the beam accelerated on the falling side of the RF waveform in conjunction with positive momentum compaction (R56) to compress the bunch. The success of this experiment motivated the design of a modified CEBAF-style arc with control of CSR and microbunching effects.

  11. Time-dependent Radiation Transfer in the Internal Shock Model Scenario for Blazar Jets

    E-Print Network [OSTI]

    Manasvita Joshi; Markus Boettcher

    2010-11-13T23:59:59.000Z

    We describe the time-dependent radiation transfer in blazar jets, within the internal shock model. We assume that the central engine, which consists of a black hole and an accretion disk, spews out relativistic shells of plasma with different velocity, mass, and energy. We consider a single inelastic collision between a faster (inner) and a slower (outer) moving shell. We study the dynamics of the collision and evaluate the subsequent emission of radiation via the synchrotron and synchrotron self Compton (SSC) processes after the interaction between the two shells has begun. The collision results in the formation of a forward shock (FS) and a reverse shock (RS) that convert the ordered bulk kinetic energy of the shells into magnetic field energy and accelerate the particles, which then radiate. We assume a cylindrical geometry for the emission region of the jet. We treat the self-consistent radiative transfer by taking into account the inhomogeneity in the photon density throughout the region. In this paper, we focus on understanding the effects of varying relevant input parameters on the simulated spectral energy distribution (SED) and spectral variability patterns.

  12. MODELING THE DYNAMICAL COUPLING OF SOLAR CONVECTION WITH THE RADIATIVE INTERIOR

    SciTech Connect (OSTI)

    Brun, Allan Sacha [Laboratoire AIM Paris-Saclay, CEA/Irfu Universite Paris-Diderot CNRS/INSU, 91191 Gif-sur-Yvette (France); Miesch, Mark S. [High Altitude Observatory, NCAR, Boulder, CO 80307-3000 (United States); Toomre, Juri [JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309-0440 (United States)

    2011-12-01T23:59:59.000Z

    The global dynamics of a rotating star like the Sun involves the coupling of a highly turbulent convective envelope overlying a seemingly benign radiative interior. We use the anelastic spherical harmonic code to develop a new class of three-dimensional models that nonlinearly couple the convective envelope to a deep stable radiative interior. The numerical simulation assumes a realistic solar stratification from r = 0.07 up to 0.97R (with R the solar radius), thus encompassing part of the nuclear core up through most of the convection zone. We find that a tachocline naturally establishes itself between the differentially rotating convective envelope and the solid body rotation of the interior, with a slow spreading that is here diffusively controlled. The rapid angular momentum redistribution in the convective envelope leads to a fast equator and slow poles, with a conical differential rotation achieved at mid-latitudes, much as has been deduced by helioseismology. The convective motions are able to overshoot downward about 0.04R into the radiative interior. However, the convective meridional circulation there is confined to a smaller penetration depth and is directed mostly equatorward at the base of the convection zone. Thermal wind balance is established in the lower convection zone and tachocline but departures are evident in the upper convection zone. Internal gravity waves are excited by the convective overshooting, yielding a complex wave field throughout the radiative interior.

  13. Development of a combined model of tissue kinetics and radiation response of human bronchiolar epithelium with single cell resolution 

    E-Print Network [OSTI]

    Ostrovskaya, Natela Grigoryevna

    2006-10-30T23:59:59.000Z

    Lack of accurate data for epidemiological studies of low dose radiation effects necessitates development of dosimetric models allowing prediction of cancer risks for different organs. The objective of this work is to develop ...

  14. Investigation of Thin Cirrus Cloud Optical and Microphysical Properties on the Basis of Satellite Observations and Fast Radiative Transfer Models 

    E-Print Network [OSTI]

    Wang, Chenxi

    2013-07-25T23:59:59.000Z

    observations and fast radiative transfer models (RTMs). In the first part, we develop two computationally efficient RTMs simulating satellite observations under cloudy-sky conditions in the visible/shortwave infrared (VIS/SWIR) and thermal inferred (IR...

  15. A parametric study of shock jump chemistry, electron temperature, and radiative heat transfer models in hypersonic flows

    E-Print Network [OSTI]

    Greendyke, Robert Brian

    1988-01-01T23:59:59.000Z

    A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN GREENDYKE Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1988 Major Subject: Aerospace Engineering A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN...

  16. Incorporating Single-nucleotide Polymorphisms Into the Lyman Model to Improve Prediction of Radiation Pneumonitis

    SciTech Connect (OSTI)

    Tucker, Susan L., E-mail: sltucker@mdanderson.org [Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Li Minghuan [Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong (China)] [Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong (China); Xu Ting; Gomez, Daniel [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Yuan Xianglin [Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China)] [Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Yu Jinming [Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong (China)] [Department of Radiation Oncology, Shandong Cancer Hospital, Jinan, Shandong (China); Liu Zhensheng; Yin Ming; Guan Xiaoxiang; Wang Lie; Wei Qingyi [Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mohan, Radhe [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Vinogradskiy, Yevgeniy [University of Colorado School of Medicine, Aurora, Colorado (United States)] [University of Colorado School of Medicine, Aurora, Colorado (United States); Martel, Mary [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liao Zhongxing [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-01-01T23:59:59.000Z

    Purpose: To determine whether single-nucleotide polymorphisms (SNPs) in genes associated with DNA repair, cell cycle, transforming growth factor-{beta}, tumor necrosis factor and receptor, folic acid metabolism, and angiogenesis can significantly improve the fit of the Lyman-Kutcher-Burman (LKB) normal-tissue complication probability (NTCP) model of radiation pneumonitis (RP) risk among patients with non-small cell lung cancer (NSCLC). Methods and Materials: Sixteen SNPs from 10 different genes (XRCC1, XRCC3, APEX1, MDM2, TGF{beta}, TNF{alpha}, TNFR, MTHFR, MTRR, and VEGF) were genotyped in 141 NSCLC patients treated with definitive radiation therapy, with or without chemotherapy. The LKB model was used to estimate the risk of severe (grade {>=}3) RP as a function of mean lung dose (MLD), with SNPs and patient smoking status incorporated into the model as dose-modifying factors. Multivariate analyses were performed by adding significant factors to the MLD model in a forward stepwise procedure, with significance assessed using the likelihood-ratio test. Bootstrap analyses were used to assess the reproducibility of results under variations in the data. Results: Five SNPs were selected for inclusion in the multivariate NTCP model based on MLD alone. SNPs associated with an increased risk of severe RP were in genes for TGF{beta}, VEGF, TNF{alpha}, XRCC1 and APEX1. With smoking status included in the multivariate model, the SNPs significantly associated with increased risk of RP were in genes for TGF{beta}, VEGF, and XRCC3. Bootstrap analyses selected a median of 4 SNPs per model fit, with the 6 genes listed above selected most often. Conclusions: This study provides evidence that SNPs can significantly improve the predictive ability of the Lyman MLD model. With a small number of SNPs, it was possible to distinguish cohorts with >50% risk vs <10% risk of RP when they were exposed to high MLDs.

  17. Determination of High-Frequency Current Distribution Using EMTP-Based Transmission Line Models with Resulting Radiated Electromagnetic Fields

    SciTech Connect (OSTI)

    Mork, B; Nelson, R; Kirkendall, B; Stenvig, N

    2009-11-30T23:59:59.000Z

    Application of BPL technologies to existing overhead high-voltage power lines would benefit greatly from improved simulation tools capable of predicting performance - such as the electromagnetic fields radiated from such lines. Existing EMTP-based frequency-dependent line models are attractive since their parameters are derived from physical design dimensions which are easily obtained. However, to calculate the radiated electromagnetic fields, detailed current distributions need to be determined. This paper presents a method of using EMTP line models to determine the current distribution on the lines, as well as a technique for using these current distributions to determine the radiated electromagnetic fields.

  18. Characterization of vegetation properties: Canopy modeling of pinyon-juniper and ponderosa pine woodlands; Final report. Modeling topographic influences on solar radiation: A manual for the SOLARFLUX model

    SciTech Connect (OSTI)

    Rich, P.M.; Hetrick, W.A.; Saving, S.C.

    1994-12-31T23:59:59.000Z

    This report is comprised of two studies. The first study focuses on plant canopies in pinyon-juniper woodland, ponderosa pine woodland, and waste sites at Los Alamos National Laboratory which involved five basic areas of research: (1) application of hemispherical photography and other gap fraction techniques to study solar radiation regimes and canopy architecture, coupled with application of time-domain reflectometry to study soil moisture; (2) detailed characterization of canopy architecture using stand mapping and allometry; (3) development of an integrated geographical information system (GIS) database for relating canopy architecture with ecological, hydrological, and system modeling approaches; (4) development of geometric models that simulate complex sky obstruction, incoming solar radiation for complex topographic surfaces, and the coupling of incoming solar radiation with energy and water balance, with simulations of incoming solar radiation for selected native vegetation and experimental waste cover design sites; and (5) evaluation of the strengths and limitations of the various field sampling techniques. The second study describes an approach to develop software that takes advantage of new generation computers to model insolation on complex topographic surfaces. SOLARFLUX is a GIS-based (ARC/INFO, GRID) computer program that models incoming solar radiation based on surface orientation (slope and aspect), solar angle (azimuth and zenith) as it shifts over time, shadows caused by topographic features, and atmospheric conditions. This manual serves as the comprehensive guide to SOLARFLUX. Included are discussions on modelling insolation on complex surfaces, the theoretical approach, program setup and operation, and a set of applications illustrating characteristics of topographic insolation modelling.

  19. Constraints on Blazar Jet Conditions During Gamma-Ray Flaring from Radiative Transfer Modeling

    E-Print Network [OSTI]

    Aller, Margo F; Aller, Hugh D; Hovatta, Talvikki

    2013-01-01T23:59:59.000Z

    As part of a program to investigate jet flow conditions during GeV gamma-ray flares detected by Fermi, we are using UMRAO multi-frequency, centimeter-band total flux density and linear polarization monitoring observations to constrain radiative transfer models incorporating propagating shocks orientated at an arbitrary angle to the flow direction. We describe the characteristics of the model, illustrate how the data are used to constrain the models, and present results for three program sources with diverse characteristics: PKS 0420-01, OJ 287, and 1156+295. The modeling of the observed spectral behavior yields information on the sense, strength and orientation of the shocks producing the radio-band flaring; on the energy distribution of the radiating particles; and on the observer's viewing angle with respect to the jet independent of VLBI data. We present evidence that, while a random component dominates the jet magnetic field, a distinguishing feature of those radio events with an associated gamma-ray flar...

  20. A fast method for Stokes profile synthesis -- Radiative transfer modeling for ZDI and Stokes profile inversion

    E-Print Network [OSTI]

    T. A. Carroll; M. Kopf; K. G. Strassmeier

    2008-07-24T23:59:59.000Z

    The major challenges for a fully polarized radiative transfer driven approach to Zeeman-Doppler imaging are still the enormous computational requirements. In every cycle of the iterative interplay between the forward process (spectral synthesis) and the inverse process (derivative based optimization) the Stokes profile synthesis requires several thousand evaluations of the polarized radiative transfer equation for a given stellar surface model. To cope with these computational demands and to allow for the incorporation of a full Stokes profile synthesis into Doppler- and Zeeman-Doppler imaging applications as well as into large scale solar Stokes profile inversions, we present a novel fast and accurate synthesis method for calculating local Stokes profiles. Our approach is based on artificial neural network models, which we use to approximate the complex non-linear mapping between the most important atmospheric parameters and the corresponding Stokes profiles. A number of specialized artificial neural networks, are used to model the functional relation between the model atmosphere, magnetic field strength, field inclination, and field azimuth, on one hand and the individual components (I,Q,U,V) of the Stokes profiles, on the other hand. We performed an extensive statistical evaluation and show that our new approach yields accurate local as well as disk-integrated Stokes profiles over a wide range of atmospheric conditions. The mean rms errors for the Stokes I and V profiles are well below 0.2% compared to the exact numerical solution. Errors for Stokes Q and U are in the range of 1%. Our approach does not only offer an accurate approximation to the LTE polarized radiative transfer it, moreover, accelerates the synthesis by a factor of more than 1000.

  1. Modeling the comfort effects of short-wave solar radiation indoors

    E-Print Network [OSTI]

    Arens, Edward; Huang, Li; Hoyt, Tyler; Zhou, Xin; Schiavon, Stefano

    2014-01-01T23:59:59.000Z

    effects of short-wave solar radiation indoors. Building andEFFECTS OF SHORT-WAVE SOLAR RADIATION INDOORS Edward ARENSK. The effects of solar radiation on thermal comfort.

  2. Friedmann-like collapsing model of a radiating sphere with heat flow

    SciTech Connect (OSTI)

    Kolassis, C.A.; Santos, N.O.; Tsoubelis, D.

    1988-04-01T23:59:59.000Z

    This paper considers a spherical body consisting of a fluid with heat flow which radiates in its exterior a null fluid described by the outgoing Vaidya's metric. A Friedmann-like exact solution of the interior Einstein field equations is given. It is proved that this solution, matched with the outgoing Vaidya matric, represents a physically reasonble collapsing model which, when the heat flow is switched off, reduces to the well-known collapsing model with dust. The proposed model has the remarkable property that even if the heat flow is small, the horizon will never be formed because, before this happens, the collapsing body will be destroyed by opposite gradients of pressure. 6 references.

  3. Validation of the Poisson Stochastic Radiative Transfer Model Against Cloud Cascade Models

    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 SpinPrincetonUsing Maps toValidatingCloudPoisson Stochastic Radiative

  4. Radiation Parameterization for Three-Dimensional Inhomogeneous Cirrus Clouds Applied to ARM Data and Climate Models

    SciTech Connect (OSTI)

    Kuo-Nan Liou

    2003-12-29T23:59:59.000Z

    OAK-B135 (a) We developed a 3D radiative transfer model to simulate the transfer of solar and thermal infrared radiation in inhomogeneous cirrus clouds. The model utilized a diffusion approximation approach (four-term expansion in the intensity) employing Cartesian coordinates. The required single-scattering parameters, including the extinction coefficient, single-scattering albedo, and asymmetry factor, for input to the model, were parameterized in terms of the ice water content and mean effective ice crystal size. The incorporation of gaseous absorption in multiple scattering atmospheres was accomplished by means of the correlated k-distribution approach. In addition, the strong forward diffraction nature in the phase function was accounted for in each predivided spatial grid based on a delta-function adjustment. The radiation parameterization developed herein is applied to potential cloud configurations generated from GCMs to investigate broken clouds and cloud-overlapping effects on the domain-averaged heating rate. Cloud inhomogeneity plays an important role in the determination of flux and heating rate distributions. Clouds with maximum overlap tend to produce less heating than those with random overlap. Broken clouds show more solar heating as well as more IR cooling as compared to a continuous cloud field (Gu and Liou, 2001). (b) We incorporated a contemporary radiation parameterization scheme in the UCLA atmospheric GCM in collaboration with the UCLA GCM group. In conjunction with the cloud/radiation process studies, we developed a physically-based cloud cover formation scheme in association with radiation calculations. The model clouds were first vertically grouped in terms of low, middle, and high types. Maximum overlap was then used for each cloud type, followed by random overlap among the three cloud types. Fu and Liou's 1D radiation code with modification was subsequently employed for pixel-by-pixel radiation calculations in the UCLA GCM. We showed that the simulated cloud cover and OLR fields without special tuning are comparable to those of ISCCP dataset and the results derived from radiation budget experiments. Use of the new radiation and cloud schemes enhances the radiative warming in the middle to upper tropical troposphere and alleviates the cold bias in the UCLA atmospheric GCM. We also illustrated that ice crystal size and cloud inhomogeneous are significant factors affecting the radiation budgets at the top of the atmosphere and the surface (Gu et al. 2003). (c) An innovative approach has been developed to construct a 3D field of inhomogeneous clouds in general and cirrus in particular in terms of liquid/ice water content and particle size on the basis of a unification of satellite and ground-based cloud radar data. Satellite remote sensing employing the current narrow-band spectro-radiometers has limitation and only the vertically integrated cloud parameters (optical depth and mean particle size) can be determined. However, by combining the horizontal cloud mapping inferred from satellites with the vertical structure derived from the profiling Doppler cloud radar, a 3D cloud field can be constructed. This represents a new conceptual approach to 3D remote sensing and imaging and offers a new perspective in observing the cloud structure. We applied this novel technique to AVHRR/NOAA satellite and mm-wave cloud radar data obtained from the ARM achieve and assessed the 3D cirrus cloud field with the ice crystal size distributions independently derived from optical probe measurements aboard the University of North Dakota Citation. The retrieved 3D ice water content and mean effective ice crystal size involving an impressive cirrus cloud occurring on April 18, 1997, are shown to be comparable to those derived from the analysis of collocated and coincident in situ aircraft measurements (Liou et al. 2002). (d) Detection of thin cirrus with optical depths less than 0.5, particularly those occurring i n the tropics remains a fundamental problem in remote sensing. We developed a new detection scheme for the

  5. Time series modeling and large scale global solar radiation forecasting from geostationary satellites data

    E-Print Network [OSTI]

    Voyant, Cyril; Muselli, Marc; Paoli, Christophe; Nivet, Marie Laure

    2014-01-01T23:59:59.000Z

    When a territory is poorly instrumented, geostationary satellites data can be useful to predict global solar radiation. In this paper, we use geostationary satellites data to generate 2-D time series of solar radiation for the next hour. The results presented in this paper relate to a particular territory, the Corsica Island, but as data used are available for the entire surface of the globe, our method can be easily exploited to another place. Indeed 2-D hourly time series are extracted from the HelioClim-3 surface solar irradiation database treated by the Heliosat-2 model. Each point of the map have been used as training data and inputs of artificial neural networks (ANN) and as inputs for two persistence models (scaled or not). Comparisons between these models and clear sky estimations were proceeded to evaluate the performances. We found a normalized root mean square error (nRMSE) close to 16.5% for the two best predictors (scaled persistence and ANN) equivalent to 35-45% related to ground measurements. F...

  6. Evolution of Meteorological Base Models for Estimating Hourly Global Solar Radiation in Texas

    E-Print Network [OSTI]

    Kim, H.; Baltazar, J.C.; Haberl, J.S

    ESL-PA-13-11-01 Available online at www.sciencedirect.com Energy Procedia 00 (2013) 000–000 www.elsevier.com/locate/procedia 2013 ISES Solar World Congress Evaluation of Meteorological Base Models... for Estimating Hourly Global Solar Radiation in Texas Kee Han Kima,b*, Juan-Carlos Baltazarb, and Jeff S. Haberla,b aDepartment of Architecture, Texas A&M University, 3137 TAMU, College Station, TX 77843-3137, U.S.A. bEnergy Systems Laboratory, Texas A...

  7. Polarization of high-energy pulsar radiation in the striped wind model

    E-Print Network [OSTI]

    J. Petri; J. Kirk

    2005-05-20T23:59:59.000Z

    The Stokes parameters of the pulsed synchrotron radiation produced in the striped pulsar wind model are computed and compared with optical observations of the Crab pulsar. We assume the main contribution to the wind emissivity comes from a thin transition layer where the dominant toroidal magnetic field reverses its polarity. The radial component of the field is neglected, but a small meridional component is added. The resulting radiation is linearly polarized (Stokes V=0). In the off-pulse region, the electric vector lies in the direction of the projection on the sky of the rotation axis of the pulsar. This property is unique to the wind model and in good agreement with the data. Other properties such as a reduced degree of polarization and a characteristic sweep of the polarization angle within the pulses are also reproduced. These properties are qualitatively unaffected by variations of the wind Lorentz factor, the electron injection power law index and the inclination of the line of sight.

  8. A Realizability-Preserving Discontinuous Galerkin Method for the $M_1$ Model of Radiative Transfer

    SciTech Connect (OSTI)

    Frank, Martin [RWTH Aachen University; Olbrant, Edgar [RWTH Aachen University; Hauck, Cory D [ORNL

    2012-01-01T23:59:59.000Z

    The M{sub 1} model for radiative transfer coupled to a material energy equation in planar geometry is studied in this paper. For this model to be well-posed, its moment variables must fulfill certain realizability conditions. Our main focus is the design and implementation of an explicit Runge-Kutta discontinuous Galerkin method which, under a more restrictive CFL condition, guarantees the realizability of the moment variables and the positivity of the material temperature. An analytical proof for our realizability-preserving scheme, which also includes a slope-limiting technique, is provided and confirmed by various numerical examples. Among other things, we present accuracy tests showing convergence up to fourth-order, compare our results with an analytical solution in a Riemann problem, and consider a Marshak wave problem.

  9. Validated Models for Radiation Response and Signal Generation in Scintillators: Final Report

    SciTech Connect (OSTI)

    Kerisit, Sebastien N.; Gao, Fei; Xie, YuLong; Campbell, Luke W.; Van Ginhoven, Renee M.; Wang, Zhiguo; Prange, Micah P.; Wu, Dangxin

    2014-12-01T23:59:59.000Z

    This Final Report presents work carried out at Pacific Northwest National Laboratory (PNNL) under the project entitled “Validated Models for Radiation Response and Signal Generation in Scintillators” (Project number: PL10-Scin-theor-PD2Jf) and led by Drs. Fei Gao and Sebastien N. Kerisit. This project was divided into four tasks: 1) Electronic response functions (ab initio data model) 2) Electron-hole yield, variance, and spatial distribution 3) Ab initio calculations of information carrier properties 4) Transport of electron-hole pairs and scintillation efficiency Detailed information on the results obtained in each of the four tasks is provided in this Final Report. Furthermore, published peer-reviewed articles based on the work carried under this project are included in Appendix. This work was supported by the National Nuclear Security Administration, Office of Nuclear Nonproliferation Research and Development (DNN R&D/NA-22), of the U.S. Department of Energy (DOE).

  10. Radiative hydrodynamic modelling and observations of the X-class solar flare on 2011 March 9

    E-Print Network [OSTI]

    Kennedy, Michael B; Allred, Joel C; Mathioudakis, Mihalis; Keenan, Francis P

    2015-01-01T23:59:59.000Z

    We investigated the response of the solar atmosphere to non-thermal electron beam heating using the radiative transfer and hydrodynamics modelling code RADYN. The temporal evolution of the parameters that describe the non-thermal electron energy distribution were derived from hard X-ray observations of a particular flare, and we compared the modelled and observed parameters. The evolution of the non-thermal electron beam parameters during the X1.5 solar flare on 2011 March 9 were obtained from analysis of RHESSI X-ray spectra. The RADYN flare model was allowed to evolve for 110 seconds, after which the electron beam heating was ended, and was then allowed to continue evolving for a further 300s. The modelled flare parameters were compared to the observed parameters determined from extreme-ultraviolet spectroscopy. The model produced a hotter and denser flare loop than that observed and also cooled more rapidly, suggesting that additional energy input in the decay phase of the flare is required. In the explosi...

  11. An enriched finite element model with q-refinement for radiative boundary layers in glass cooling

    SciTech Connect (OSTI)

    Mohamed, M. Shadi [Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)] [Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Seaid, Mohammed; Trevelyan, Jon [School of Engineering and Computing Sciences, University of Durham, South Road, Durham DH1 3LE (United Kingdom)] [School of Engineering and Computing Sciences, University of Durham, South Road, Durham DH1 3LE (United Kingdom); Laghrouche, Omar [Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)] [Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

    2014-02-01T23:59:59.000Z

    Radiative cooling in glass manufacturing is simulated using the partition of unity finite element method. The governing equations consist of a semi-linear transient heat equation for the temperature field and a stationary simplified P{sub 1} approximation for the radiation in non-grey semitransparent media. To integrate the coupled equations in time we consider a linearly implicit scheme in the finite element framework. A class of hyperbolic enrichment functions is proposed to resolve boundary layers near the enclosure walls. Using an industrial electromagnetic spectrum, the proposed method shows an immense reduction in the number of degrees of freedom required to achieve a certain accuracy compared to the conventional h-version finite element method. Furthermore the method shows a stable behaviour in treating the boundary layers which is shown by studying the solution close to the domain boundaries. The time integration choice is essential to implement a q-refinement procedure introduced in the current study. The enrichment is refined with respect to the steepness of the solution gradient near the domain boundary in the first few time steps and is shown to lead to a further significant reduction on top of what is already achieved with the enrichment. The performance of the proposed method is analysed for glass annealing in two enclosures where the simplified P{sub 1} approximation solution with the partition of unity method, the conventional finite element method and the finite difference method are compared to each other and to the full radiative heat transfer as well as the canonical Rosseland model.

  12. On the spontaneous emission of electromagnetic radiation in the CSL model

    SciTech Connect (OSTI)

    Donadi, Sandro, E-mail: sandro.donadi@ts.infn.it [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy) [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy); Istituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127 Trieste (Italy); Deckert, Dirk-André, E-mail: deckert@math.ucdavis.edu [Department of Mathematics, University of California, One Shields Ave, 95616 Davis (United States)] [Department of Mathematics, University of California, One Shields Ave, 95616 Davis (United States); Bassi, Angelo, E-mail: bassi@ts.infn.it [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy) [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy); Istituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127 Trieste (Italy)

    2014-01-15T23:59:59.000Z

    Spontaneous photon emission in the Continuous Spontaneous Localization (CSL) model is studied one more time. In the CSL model each particle interacts with a noise field that induces the collapse of its wave function. As a consequence of this interaction, when the particle is electrically charged, it radiates. As discussed in Adler (2013) the formula for the emission rate, to first perturbative order, contains two terms: one is proportional to the Fourier component of the noise field at the same frequency as that of the emitted photon and one is proportional to the zero Fourier component of the noise field. As discussed in previous works, this second term seems unphysical. In Adler (2013) it was shown that the unphysical term disappears when the noise is confined to a bounded region and the final particle’s state is a wave packet. Here we investigate the origin of this unphysical term and why it vanishes according to the previous prescription. We will see that perturbation theory is formally not valid in the large time limit since the effect of the noise accumulates continuously in time. Therefore either one performs an exact calculation (or at least in some way includes higher order terms) as we do here, or one finds a way to make a perturbative calculation meaningful, e.g., by confining the system as in Adler (2013). -- Highlights: •We compute the electromagnetic radiation emission in collapse models. •Under only the dipole approximation, the equations of motion are solved exactly. •The electromagnetic interaction must be treated exactly. •In order to obtain the correct emission rate the particle must be bounded.

  13. Impact of subgrid-scale radiative heating variability on the stratocumulus-to-trade cumulus transition in climate models

    SciTech Connect (OSTI)

    Xiao, Heng; Gustafson, William I.; Wang, Hailong

    2014-04-29T23:59:59.000Z

    Subgrid-scale interactions between turbulence and radiation are potentially important for accurately reproducing marine low clouds in climate models. To better understand the impact of these interactions, the Weather Research and Forecasting (WRF) model is configured for large eddy simulation (LES) to study the stratocumulus-to-trade cumulus (Sc-to-Cu) transition. Using the GEWEX Atmospheric System Studies (GASS) composite Lagrangian transition case and the Atlantic Trade Wind Experiment (ATEX) case, it is shown that the lack of subgrid-scale turbulence-radiation interaction, as is the case in current generation climate models, accelerates the Sc-to-Cu transition. Our analysis suggests that in cloud-topped boundary layers subgrid-scale turbulence-radiation interactions contribute to stronger production of temperature variance, which in turn leads to stronger buoyancy production of turbulent kinetic energy and helps to maintain the Sc cover.

  14. An Analytical Model of Radiation-Induced Charge Transfer Inefficiency for CCD Detectors

    E-Print Network [OSTI]

    Short, Alexander; de Bruijne, Jos H J; Prod'homme, Thibaut

    2013-01-01T23:59:59.000Z

    The European Space Agency's Gaia mission is scheduled for launch in 2013. It will operate at L2 for 5 years, rotating slowly to scan the sky so that its two optical telescopes will repeatedly observe more than one billion stars. The resulting data set will be iteratively reduced to solve for the position, parallax and proper motion of every observed star. The focal plane contains 106 large area silicon CCDs continuously operating in a mode where the line transfer rate and the satellite rotation are in synchronisation. One of the greatest challenges facing the mission is radiation damage to the CCDs which will cause charge deferral and image shape distortion. This is particularly important because of the extreme accuracy requirements of the mission. Despite steps taken at hardware level to minimise the effects of radiation, the residual distortion will need to be calibrated during the pipeline data processing. Due to the volume and inhomogeneity of data involved, this requires a model which describes the effec...

  15. Radiative Generation of Quark Masses and Mixing Angles in the Two Higgs Doublet Model

    E-Print Network [OSTI]

    Alejandro Ibarra; Ana Solaguren-Beascoa

    2014-07-04T23:59:59.000Z

    We present a framework to generate the quark mass hierarchies and mixing angles by extending the Standard Model with one extra Higgs doublet. The charm and strange quark masses are generated by small quantum effects, thus explaining the hierarchy between the second and third generation quark masses. All the mixing angles are also generated by small quantum effects: the Cabibbo angle is generated at zero-th order in perturbation theory, while the remaining off-diagonal entries of the Cabibbo-Kobayashi-Maskawa matrix are generated at first order, hence explaining the observed hierarchy $|V_{ub}|,|V_{cb}|\\ll |V_{us}|$. The values of the radiatively generated parameters depend only logarithmically on the heavy Higgs mass, therefore this framework can be reconciled with the stringent limits on flavor violation by postulating a sufficiently large new physics scale.

  16. Radiation Damage in Nuclear Fuel for Advanced Burner Reactors: Modeling and Experimental Validation

    SciTech Connect (OSTI)

    Jensen, Niels Gronbech; Asta, Mark; Ozolins, Nigel Browning'Vidvuds; de Walle, Axel van; Wolverton, Christopher

    2011-12-29T23:59:59.000Z

    The consortium has completed its existence and we are here highlighting work and accomplishments. As outlined in the proposal, the objective of the work was to advance the theoretical understanding of advanced nuclear fuel materials (oxides) toward a comprehensive modeling strategy that incorporates the different relevant scales involved in radiation damage in oxide fuels. Approaching this we set out to investigate and develop a set of directions: 1) Fission fragment and ion trajectory studies through advanced molecular dynamics methods that allow for statistical multi-scale simulations. This work also includes an investigation of appropriate interatomic force fields useful for the energetic multi-scale phenomena of high energy collisions; 2) Studies of defect and gas bubble formation through electronic structure and Monte Carlo simulations; and 3) an experimental component for the characterization of materials such that comparisons can be obtained between theory and experiment.

  17. Modeling radiation-induced mixing at interfaces between low solubility metals

    E-Print Network [OSTI]

    Zhang, Liang, Ph. D. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    This thesis studies radiation-induced mixing at interfaces between low solubility metals using molecular dynamics (MD) computer simulations. It provides original contributions on the fundamental mechanisms of radiation-induced ...

  18. Modeling the comfort effects of short-wave solar radiation indoors

    E-Print Network [OSTI]

    Arens, Edward; Hoyt, Tyler; Zhou, Xin; Huang, Li; Zhang, Hui; Schiavon, Stefano

    2015-01-01T23:59:59.000Z

    2004. [3] Blum HF. Solar heat load, its relationship to theS, Parsons K. The effects of solar radiation on thermalParsons K. The effects of solar radiation and black body re-

  19. Modeling the radiation belt electrons with radial diffusion driven by the solar wind

    E-Print Network [OSTI]

    Li, Xinlin

    in the enhancement of radiation belt electrons yet leaves a significant portion of the variance unaccounted for. We

  20. Interactive dust-radiation modeling: A step to improve weather Carlos Perez,1

    E-Print Network [OSTI]

    radiative effects could lead to a significant improvement in the radiation balance of numerical weather 2002 is selected to assess the radiative dust effects on the atmosphere at a regional level. A strong unresolved and depend on the optical properties of dust, its vertical distribution, cloud cover, and albedo

  1. Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical transport model

    E-Print Network [OSTI]

    Liu, Hongyu

    Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical. (2006), Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical frequencies are calculated using the Fast-J radiative transfer algorithm. The GEOS-3 global cloud optical

  2. A radiative-convective equilibrium model to study young giant exoplanets by direct imaging

    E-Print Network [OSTI]

    Baudino, J -L; Boccaletti, A; Bonnefoy, M; Lagrange, A M; Galicher, R

    2015-01-01T23:59:59.000Z

    We developed a model for young giant exoplanets (Exoplanet Radiative-convective Equilibrium Model or Exo-REM). Input parameters are planet's surface gravity (g), effective temperature (Teff ) and elemental composition. Under the additional assumption of thermochemical equilibrium, the model predicts the equilibrium temperature profile and mixing ratio profiles of the most important gases. Opacity sources include the H$_2$-He collision-induced absorption and molecular lines from H$_2$O, CO, CH$_4$ (updated with the Exomol linelist), NH$_3$, VO, TiO, Na and K. Absorption by iron and silicate cloud particles is added above the expected condensation levels with a fixed scale height and a given optical depth at some reference wavelength. Scattering was not included at this stage. We applied Exo-REM to photometric and spectral observations of the planet beta Pictoris b obtained in a series of near IR filters. We derived Teff = 1550 $\\pm$ 150 K, log(g) = 3.5 $\\pm$ 1, and a radius R = 1.76 $\\pm$ 0.24 R Jup (2-$\\sigma...

  3. Combined Modeling of Acceleration, Transport, and Hydrodynamic Response in Solar Flares. II. Inclusion of Radiative Transfer with RADYN

    E-Print Network [OSTI]

    da Costa, Fatima Rubio; Petrosian, Vahe'; Carlsson, Mats

    2015-01-01T23:59:59.000Z

    Solar flares involve complex processes that are coupled together and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present such a model to simulate the coupling of high-energy particle kinetics with hydrodynamics of the atmospheric plasma. We combine the Stanford unified Fokker-Planck code that models particle acceleration, transport, and bremsstrahlung radiation with the RADYN hydrodynamic code that models the atmospheric response to collisional heating by non-thermal electrons through detailed radiative transfer calculations. We perform simulations using different injection electron spectra, including an {\\it ad hoc} power law and more realistic spectra predicted by the stochastic acceleration model due to turbulence or plasma waves. Surprisingly, stochastically accelerated electrons, even with energy flux $\\ll 10^{10}$ erg s$^{-1}$ cm$^{-2}$, cause "explosive" chromospheric evaporation and drive stronger up- an...

  4. Regional Modeling of Dust Mass Balance and Radiative Forcing over East Asia using WRF-Chem

    SciTech Connect (OSTI)

    Chen, Siyu; Zhao, Chun; Qian, Yun; Leung, Lai-Yung R.; Huang, J.; Huang, Zhongwei; Bi, Jianrong; Zhang, Wu; Shi, Jinsen; Yang, Lei; Li, Deshuai; Li, Jinxin

    2014-12-01T23:59:59.000Z

    The Weather Research and Forecasting model with Chemistry (WRF-Chem) is used to investigate the seasonal and annual variations of mineral dust over East Asia during 2007-2011, with a focus on the dust mass balance and radiative forcing. A variety of measurements from in-stu and satellite observations have been used to evaluate simulation results. Generally, WRF-Chem reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions of East Asia. We investigate the dust lifecycle and the factors that control the seasonal and spatial variations of dust mass balance and radiative forcing over the seven sub-regions of East Asia, i.e. source regions, the Tibetan Plateau, Northern China, Southern China, the ocean outflow region, and Korea-Japan regions. Results show that, over the source regions, transport and dry deposition are the two dominant sinks. Transport contributes to ~30% of the dust sink over the source regions. Dust results in a surface cooling of up to -14 and -10 W m-2, atmospheric warming of up to 20 and 15 W m-2, and TOA cooling of -5 and -8 W m-2 over the two major dust source regions of East Asia, respectively. Over the Tibetan Plateau, transport is the dominant source with a peak in summer. Over identified outflow regions, maximum dust mass loading in spring is contributed by the transport. Dry and wet depositions are the comparably dominant sinks, but wet deposition is larger than dry deposition over the Korea-Japan region, particularly in spring (70% versus 30%). The WRF-Chem simulations can generally capture the measured features of dust aerosols and its radaitve properties and dust mass balance over East Asia, which provides confidence for use in further investigation of dust impact on climate over East Asia.

  5. Solar surface emerging flux regions: a comparative study of radiative MHD modeling and Hinode SOT observations

    E-Print Network [OSTI]

    M. C. M. Cheung; M. Schuessler; T. D. Tarbell; A. M. Title

    2008-10-31T23:59:59.000Z

    We present results from numerical modeling of emerging flux regions on the solar surface. The modeling was carried out by means of 3D radiative MHD simulations of the rise of buoyant magnetic flux tubes through the convection zone and into the photosphere. Due to the strong stratification of the convection zone, the rise results in a lateral expansion of the tube into a magnetic sheet, which acts as a reservoir for small-scale flux emergence events at the scale of granulation. The interaction of the convective downflows and the rising magnetic flux undulates it to form serpentine field lines emerging into the photosphere. Observational characteristics including the pattern of emerging flux regions, the cancellation of surface flux and associated high speed downflows, the convective collapse of photospheric flux tubes, the appearance of anomalous darkenings, the formation of bright points and the possible existence of transient kilogauss horizontal fields are discussed in the context of new observations from the Hinode Solar Optical Telescope. Implications for the local helioseismology of emerging flux regions are also discussed.

  6. Uncertainty in Modeling Dust Mass Balance and Radiative Forcing from Size Parameterization

    SciTech Connect (OSTI)

    Zhao, Chun; Chen, Siyu; Leung, Lai-Yung R.; Qian, Yun; Kok, Jasper; Zaveri, Rahul A.; Huang, J.

    2013-11-05T23:59:59.000Z

    This study examines the uncertainties in simulating mass balance and radiative forcing of mineral dust due to biases in the aerosol size parameterization. Simulations are conducted quasi-globally (180oW-180oE and 60oS-70oN) using the WRF24 Chem model with three different approaches to represent aerosol size distribution (8-bin, 4-bin, and 3-mode). The biases in the 3-mode or 4-bin approaches against a relatively more accurate 8-bin approach in simulating dust mass balance and radiative forcing are identified. Compared to the 8-bin approach, the 4-bin approach simulates similar but coarser size distributions of dust particles in the atmosphere, while the 3-mode pproach retains more fine dust particles but fewer coarse dust particles due to its prescribed og of each mode. Although the 3-mode approach yields up to 10 days longer dust mass lifetime over the remote oceanic regions than the 8-bin approach, the three size approaches produce similar dust mass lifetime (3.2 days to 3.5 days) on quasi-global average, reflecting that the global dust mass lifetime is mainly determined by the dust mass lifetime near the dust source regions. With the same global dust emission (~6000 Tg yr-1), the 8-bin approach produces a dust mass loading of 39 Tg, while the 4-bin and 3-mode approaches produce 3% (40.2 Tg) and 25% (49.1 Tg) higher dust mass loading, respectively. The difference in dust mass loading between the 8-bin approach and the 4-bin or 3-mode approaches has large spatial variations, with generally smaller relative difference (<10%) near the surface over the dust source regions. The three size approaches also result in significantly different dry and wet deposition fluxes and number concentrations of dust. The difference in dust aerosol optical depth (AOD) (a factor of 3) among the three size approaches is much larger than their difference (25%) in dust mass loading. Compared to the 8-bin approach, the 4-bin approach yields stronger dust absorptivity, while the 3-mode approach yields weaker dust absorptivity. Overall, on quasi-global average, the three size parameterizations result in a significant difference of a factor of 2~3 in dust surface cooling (-1.02~-2.87 W m-2) and atmospheric warming (0.39~0.96 W m-2) and in a tremendous difference of a factor of ~10 in dust TOA cooling (-0.24~-2.20 W m-2). An uncertainty of a factor of 2 is quantified in dust emission estimation due to the different size parameterizations. This study also highlights the uncertainties in modeling dust mass and number loading, deposition fluxes, and radiative forcing resulting from different size parameterizations, and motivates further investigation of the impact of size parameterizations on modeling dust impacts on air quality, climate, and ecosystem.

  7. A new time-dependent analytic model for radiation-induced photocurrent in finite 1D epitaxial diodes.

    SciTech Connect (OSTI)

    Verley, Jason C.; Axness, Carl L.; Hembree, Charles Edward; Keiter, Eric Richard; Kerr, Bert (New Mexico Institute of Mining and Technology, Socorro, NM)

    2012-04-01T23:59:59.000Z

    Photocurrent generated by ionizing radiation represents a threat to microelectronics in radiation environments. Circuit simulation tools such as SPICE [1] can be used to analyze these threats, and typically rely on compact models for individual electrical components such as transistors and diodes. Compact models consist of a handful of differential and/or algebraic equations, and are derived by making simplifying assumptions to any of the many semiconductor transport equations. Historically, many photocurrent compact models have suffered from accuracy issues due to the use of qualitative approximation, rather than mathematically correct solutions to the ambipolar diffusion equation. A practical consequence of this inaccuracy is that a given model calibration is trustworthy over only a narrow range of operating conditions. This report describes work to produce improved compact models for photocurrent. Specifically, an analytic model is developed for epitaxial diode structures that have a highly doped subcollector. The analytic model is compared with both numerical TCAD calculations, as well as the compact model described in reference [2]. The new analytic model compares well against TCAD over a wide range of operating conditions, and is shown to be superior to the compact model from reference [2].

  8. Assessment of advanced coal-gasification processes. [AVCO high throughput gasification in process; Bell High Mass Flux process; CS-R process; and Exxon Gasification process

    SciTech Connect (OSTI)

    McCarthy, J.; Ferrall, J.; Charng, T.; Houseman, J.

    1981-06-01T23:59:59.000Z

    This report represents a technical assessment of the following advanced coal gasification processes: AVCO High Throughput Gasification (HTG) Process, Bell Single - Stage High Mass Flux (HMF) Process, Cities Service/Rockwell (CS/R) Hydrogasification Process, and the Exxon Catalytic Coal Gasification (CCG) Process. Each process is evaluated for its potential to produce SNG from a bituminous coal. In addition to identifying the new technology these processes represent, key similarities/differences, strengths/weaknesses, and potential improvements to each process are identified. The AVCO HTG and the Bell HMF gasifiers share similarities with respect to: short residence time (SRT), high throughput rate, slagging and syngas as the initial raw product gas. The CS/R Hydrogasifier is also SRT but is non-slagging and produces a raw gas high in methane content. The Exxon CCG gasifier is a long residence time, catalytic fluidbed reactor producing all of the raw product methane in the gasifier.

  9. Global Climate Modeling of the Martian water cycle with improved microphysics and radiatively active water ice clouds

    E-Print Network [OSTI]

    Navarro, Thomas; Forget, François; Spiga, Aymeric; Millour, Ehouarn; Montmessin, Franck

    2013-01-01T23:59:59.000Z

    Radiative effects of water ice clouds have noteworthy consequences on the Martian atmosphere, its thermal structure and circulation. Accordingly, the inclusion of such effects in the LMD Mars Global Climate Model (GCM) greatly modifies the simulated Martian water cycle. The intent of this paper is to address the impact of radiatively active clouds on atmospheric water vapor and ice in the GCM and improve its representation. We propose a new enhanced modeling of the water cycle, consisting of detailed cloud microphysics with dynamic condensation nuclei and a better implementation of perennial surface water ice. This physical modeling is based on tunable parameters. This new version of the GCM is compared to the Thermal Emission Spectrometer observations of the water cycle. Satisfying results are reached for both vapor and cloud opacities. However, simulations yield a lack of water vapor in the tropics after Ls=180{\\deg} which is persistent in simulations compared to observations, as a consequence of aphelion c...

  10. Multi-horizon solar radiation forecasting for Mediterranean locations using time series models

    E-Print Network [OSTI]

    Voyant, Cyril; Muselli, Marc; Nivet, Marie Laure

    2013-01-01T23:59:59.000Z

    Considering the grid manager's point of view, needs in terms of prediction of intermittent energy like the photovoltaic resource can be distinguished according to the considered horizon: following days (d+1, d+2 and d+3), next day by hourly step (h+24), next hour (h+1) and next few minutes (m+5 e.g.). Through this work, we have identified methodologies using time series models for the prediction horizon of global radiation and photovoltaic power. What we present here is a comparison of different predictors developed and tested to propose a hierarchy. For horizons d+1 and h+1, without advanced ad hoc time series pre-processing (stationarity) we find it is not easy to differentiate between autoregressive moving average (ARMA) and multilayer perceptron (MLP). However we observed that using exogenous variables improves significantly the results for MLP . We have shown that the MLP were more adapted for horizons h+24 and m+5. In summary, our results are complementary and improve the existing prediction techniques ...

  11. The B and W Owners Group program for microstructural characterization and radiation embrittlement modelling of Linde 80 reactor vessel welds

    SciTech Connect (OSTI)

    Pavinich, W.A. [Grove Engineering, Knoxville, TN (United States); Harbison, L.S. [B and W Nuclear Technologies, Lynchburg, VA (United States)

    1996-12-31T23:59:59.000Z

    The Babcock and Wilcox Owners Group (B and WOG) is embrittlement of Linde 80 reactor vessel welds from a micro-mechanical viewpoint. Previous work that focused on characterizing the large microstructural features indicated that a large portion of the bulk copper content is in precipitate/inclusion/carbide form. This result indicates that copper in solid solution is considerably less than the bulk composition. Field-ion microscope atom probe investigations on unirradiated weld metals with bulk copper contents ranging from 0.22 to 0.38 wt%, also indicate significant amount of copper are tied up in precipitate/inclusion/carbide form. This results is significant since the bulk copper content (which includes both copper in solid solution and copper contained in precipitates, inclusions, and carbides) is used in Regulatory Guide 1.99, Revision 2 to determine radiation damage. This paper reviews these results. Existing radiation embrittlement models superpose the changes in yield strength due to defect clusters and copper-rich precipitates induced by neutron irradiation. Low-copper Linde 80 welds display little or no increase in the 41 joule (30 ft-lb) transition temperature as a result of neutron irradiation which indicates that precipitation is the dominant component of radiation embrittlement for Linde 80 welds. Future work will include further microstructural characterizations of Linde 80 reactor vessel welds and applying the existing radiation embrittlement models to Linde 80 welds. This paper describes the detailed plans for future work.

  12. Incorporation of time-dependent thermodynamic models and radiation propagation models into JR 3-D synthetic image generation models

    E-Print Network [OSTI]

    Salvaggio, Carl

    images representing what an airborne or satellite thermal infrared imaging sensor would record. The scene sensors to a point where the model can be usedas a research tool to evaluate the limitations in our infrared (TIR) imagery generated by midwave (3-5 Rm) and longwave (8-14 pm) sensors is being increasingly

  13. Evolution of Meteorological Base Models for Estimating Hourly Global Solar Radiation in Texas 

    E-Print Network [OSTI]

    Kim, H.; Baltazar, J.C.; Haberl, J.S

    2013-01-01T23:59:59.000Z

    for Estimating Hourly Global Solar Radiation in Texas Kee Han Kima,b*, Juan-Carlos Baltazarb, and Jeff S. Haberla,b aDepartment of Architecture, Texas A&M University, 3137 TAMU, College Station, TX 77843-3137, U.S.A. bEnergy Systems Laboratory, Texas A... for measured solar radiation data and, as a result, rely on the values from typical meteorological years. Texas, in a similar fashion as other states in the US, does not have an active network for solar radiation data and has a variety of weather conditions...

  14. THE PHOTOSPHERIC RADIATION MODEL FOR THE PROMPT EMISSION OF GAMMA-RAY BURSTS: INTERPRETING FOUR OBSERVED CORRELATIONS

    SciTech Connect (OSTI)

    Fan Yizhong; Wei Daming; Zhang Fuwen [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Zhang Binbin, E-mail: yzfan@pmo.ac.cn, E-mail: dmwei@pmo.ac.cn, E-mail: fwzhang@pmo.ac.cn, E-mail: bbzhang@psu.edu [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2012-08-10T23:59:59.000Z

    We show that the empirical E{sub p}-L, {Gamma}-L, E{sub p}-{Gamma}, and {eta}-bar{sub {gamma}}-E{sub p} correlations (where L is the time-averaged luminosity of the prompt emission, E{sub p} is the spectral peak energy, {Gamma} is the bulk Lorentz factor, and {eta}-bar{sub {gamma}} is the emission efficiency of gamma-ray bursts, GRBs) are well consistent with the relations between the analogous parameters predicted in the photospheric radiation model of the prompt emission of GRBs. The time-resolved thermal radiation of GRB 090902B does follow the E{sub p}-L and {Gamma}-L correlations. A reliable interpretation of the four correlations in alternative models is still lacking. These may point toward a photospheric origin of prompt emission of some GRBs.

  15. Space radiation-induced bystander signaling in 2D and 3D skin tissue models

    E-Print Network [OSTI]

    Lumpkins, Sarah B

    2012-01-01T23:59:59.000Z

    Space radiation poses a significant hazard to astronauts on long-duration missions, and the low fluences of charged particles characteristic of this field suggest that bystander effects, the phenomenon in which a greater ...

  16. MODEL STORAGE RING FOR 6 GEV OPERATION AS A SYNCHROTRON RADIATION...

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

    STORAGE RING FOR 6 GEV OPERATION AS A SYNCHROTRON RADIATION SOURCE PARAMETER LIST Comments: (- To be completed). (* To be defined by workshop) LATTICE PARAMETERS Energy (CeV) Beam...

  17. The prediction of radiation-induced liver dysfunction using a local dose and regional venous perfusion model

    SciTech Connect (OSTI)

    Cao Yue; Platt, Joel F.; Francis, Isaac R; Balter, James M.; Pan, Charlie; Normolle, Daniel; Ben-Josef, Edgar; Haken, Randall K. ten; Lawrence, Theodore S. [Departments of Radiation Oncology and Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States)

    2007-02-15T23:59:59.000Z

    We have shown that high dose conformal radiation combined with chemotherapy appears to prolong the survival of patients with unresectable intrahepatic cancers. The ability to safely deliver higher doses is primarily limited by the development of radiation-induced liver disease, characterized by venous occlusion. In this study, we investigated whether portal venous perfusion measured prior to the end of radiation therapy (RT) together with dose could predict liver venous perfusion dysfunction after treatment. Ten patients with unresectable intrahepatic cancer participated in an IRB-approved computer tomography (CT) perfusion study. Hepatic arterial and portal vein perfusion distributions were estimated by using dynamic contrast enhanced CT and the single compartmental model. Scans were obtained at four time points: prior to treatment, after 15 and 30 fractions of 1.5 Gy treatments, and one month following the completion of RT. Multivariant linear regression was used to determine covariances among the first three time point measurements plus dose for prediction of the post RT measurement. The reduction in the regional venous perfusion one month following RT was predicted by the local accumulated dose and the change in the regional venous perfusion after {approx}30 fractions (F=90.6,p<0.000 01). Each Gy produced an approximately 1.2% of reduction in the venous perfusion. This local dose and venous perfusion model has the potential to predict individual sensitivity to radiation. This is the first step toward developing a method to deliver higher and potentially more curative radiation doses to the patients who can safely receive these higher doses.

  18. Tritium: a model for low level long-term ionizing radiation exposure

    SciTech Connect (OSTI)

    Carsten, A.L.

    1984-01-01T23:59:59.000Z

    The somatic, cytogenetic and genetic effects of single and chronic tritiated water (HTO) ingestion in mice was investigated. This study serves not only as an evaluation of tritium toxicity (TRITOX) but due to its design involving long-term low concentration ingestion of HTO may serve as a model for low level long-term ionizing radiation exposure in general. Long-term studies involved animals maintained on HTO at concentrations of 0.3 ..mu..Ci/ml, 1.0 ..mu..Ci/ml, 3.0 ..mu..Ci/ml or depth dose equivalent chronic external exposures to /sup 137/Cs gamma rays. Maintenance on 3.0 ..mu..Ci/ml resulted in no effect on growth, life-time shortening or bone marrow cellularity, but did result in a reduction of bone marrow stem cells, an increase in DLM's in second generation animals maintained on this regimen and cytogenetic effects as indicated by increased sister chromatid exchanges (SCE's) in bone marrow cells, increased chromosome aberrations in the regenerating liver and an increase in micronuclei in red blood cells. Biochemical and microdosimetry studies showed that animals placed on the HTO regimen reached tritium equilibrium in the body water in approximately 17 to 21 days with a more gradual increase in bound tritium. When animals maintained for 180 days on 3.0 ..mu..Ci/ml HTO were placed on a tap water regimen, the tritium level in tissue dropped from the equilibrium value of 2.02 ..mu..Ci/ml before withdrawal to 0.001 ..mu..Ci/ml at 28 days. 18 references.

  19. Predictive Models for Regional Hepatic Function Based on 99mTc-IDA SPECT and Local Radiation Dose for Physiologic Adaptive Radiation Therapy

    SciTech Connect (OSTI)

    Wang, Hesheng, E-mail: hesheng@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Frey, Kirk A. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Ten Haken, Randall K.; Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cao, Yue [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan (United States)

    2013-08-01T23:59:59.000Z

    Purpose: High-dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed before and during the course of RT using 99mTc-labeled iminodiacetic acid (IDA) single photon emission computed tomography (SPECT) could predict regional liver function reserve after RT. Methods and Materials: Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans before RT, during, and 1 month after completion of RT. Indocyanine green (ICG) tests, a measure of overall liver function, were performed within 1 day of each scan. Three-dimensional volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After coregistration of the CT/SPECT and the treatment planning CT, HEF dose–response functions during and after RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, dose, priori, and adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function after RT. Results: The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r=?0.80, P<.0001), for all time points. Linear correlations between local doses and regional HEFs 1 month after RT were significant in 12 patients. In the priori model, regional HEF after RT was predicted by the planned dose and regional HEF assessed before RT (R=0.71, P<.0001). In the adaptive model, regional HEF after RT was predicted by regional HEF reassessed during RT and the remaining planned local dose (R=0.83, P<.0001). Conclusions: 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of liver damage.

  20. Modelled Black Carbon Radiative Forcing and Atmospheric Lifetime in AeroCom Phase II Constrained by Aircraft Observations

    SciTech Connect (OSTI)

    Samset, B. H.; Myhre, G.; Herber, Andreas; Kondo, Yutaka; Li, Shao-Meng; Moteki, N.; Koike, Makoto; Oshima, N.; Schwarz, Joshua P.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Chin, M.; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Lamarque, Jean-Francois; Lin, Guang; Liu, Xiaohong; Penner, Joyce E.; Schulz, M.; Seland, O.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; Zhang, Kai

    2014-11-27T23:59:59.000Z

    Black carbon (BC) aerosols absorb solar radiation, and are generally held to exacerbate global warming through exerting a positive radiative forcing1. However, the total contribution of BC to the ongoing changes in global climate is presently under debate2-8. Both anthropogenic BC emissions and the resulting spatial and temporal distribution of BC concentration are highly uncertain2,9. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood, leading to large estimated uncertainty in BC concentration at high altitudes and far from emission sources10. These uncertainties limit our ability to quantify both the historical, present and future anthropogenic climate impact of BC. Here we compare vertical profiles of BC concentration from four recent aircraft measurement campaigns with 13 state of the art aerosol models, and show that recent assessments may have overestimated present day BC radiative forcing. Further, an atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in transport dominated remote regions. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in the multi-model median direct BC forcing from fossil fuel and biofuel burning over the industrial era.

  1. Predicting oropharyngeal tumor volume throughout the course of radiation therapy from pretreatment computed tomography data using general linear models

    SciTech Connect (OSTI)

    Yock, Adam D., E-mail: ADYock@mdanderson.org; Kudchadker, Rajat J. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States); Rao, Arvind [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and the Graduate School of Biomedical Sciences, the University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and the Graduate School of Biomedical Sciences, the University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States); Dong, Lei [Scripps Proton Therapy Center, San Diego, California 92121 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Scripps Proton Therapy Center, San Diego, California 92121 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States); Beadle, Beth M.; Garden, Adam S. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)] [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Court, Laurence E. [Department of Radiation Physics and Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Department of Radiation Physics and Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: The purpose of this work was to develop and evaluate the accuracy of several predictive models of variation in tumor volume throughout the course of radiation therapy. Methods: Nineteen patients with oropharyngeal cancers were imaged daily with CT-on-rails for image-guided alignment per an institutional protocol. The daily volumes of 35 tumors in these 19 patients were determined and used to generate (1) a linear model in which tumor volume changed at a constant rate, (2) a general linear model that utilized the power fit relationship between the daily and initial tumor volumes, and (3) a functional general linear model that identified and exploited the primary modes of variation between time series describing the changing tumor volumes. Primary and nodal tumor volumes were examined separately. The accuracy of these models in predicting daily tumor volumes were compared with those of static and linear reference models using leave-one-out cross-validation. Results: In predicting the daily volume of primary tumors, the general linear model and the functional general linear model were more accurate than the static reference model by 9.9% (range: ?11.6%–23.8%) and 14.6% (range: ?7.3%–27.5%), respectively, and were more accurate than the linear reference model by 14.2% (range: ?6.8%–40.3%) and 13.1% (range: ?1.5%–52.5%), respectively. In predicting the daily volume of nodal tumors, only the 14.4% (range: ?11.1%–20.5%) improvement in accuracy of the functional general linear model compared to the static reference model was statistically significant. Conclusions: A general linear model and a functional general linear model trained on data from a small population of patients can predict the primary tumor volume throughout the course of radiation therapy with greater accuracy than standard reference models. These more accurate models may increase the prognostic value of information about the tumor garnered from pretreatment computed tomography images and facilitate improved treatment management.

  2. Optimization in the Parikh-Wilczek tunneling model of Hawking radiation for Kerr-Newman Black Holes

    E-Print Network [OSTI]

    Auttakit Chatrabhuti; Khem Upathambhakul

    2014-03-17T23:59:59.000Z

    In this short report, we investigate the mutual information hidden in the Parikh-Wilczek tunneling model of Hawking radiation for Kerr-Newman black holes. By assuming the radiation as an optimization process, we discuss its effect on time evolution of rotating (charged and uncharged) black holes. For uncharged rotating black holes evaporating under the maximum mutual information optimization, their scale invariant rotation parameter $a_*=a/M$ is almost constant at the early stage but rapidly increase at the very last stage of the evaluation process. The value of rotation parameter at the final state of evaporation depends on the initial condition of the black hole. We also found that the presence of electric charge can cause the black holes lose their angular momentum more rapidly than they lose mass. The charged-rotating black holes asymptotically approach a state which is described by $a_*= 0$ and $Q/M = 1$.

  3. A revised model of the kidney for medical internal radiation dose calculations

    E-Print Network [OSTI]

    Patel, Jyoti Shivabhai

    1988-01-01T23:59:59.000Z

    are frequently the organs receiving the highest level of radioactivity and, therefore, the largest radiation dose. Short lived radiopharmaceuticals, that are now injected in millicurie quantities in nuclear medicine for rapid-sequence imaging of the brain... radionuclides (Appendix B). 17 These include the following radionuclides presently used in nuclear medicine: P-32, Cr-51, Co-57, Ga-67, Tc-99m, In-ill, I-123, Xe-127, I-131, Xe-133, and T1-201. If the radionuclide emits penetrating radiation, the code...

  4. Improving a radiative plus collisional energy loss model for application to RHIC and LHC

    E-Print Network [OSTI]

    Simon Wicks; Miklos Gyulassy

    2007-06-20T23:59:59.000Z

    With the QGP opacity computed perturbatively and with the global entropy constraints imposed by the observed dNch/dy~1000, radiative energy loss alone cannot account for the observed suppression of single non-photonic electrons. Collisional energy loss is comparable in magnitude to radiative loss for both light and heavy jets. Two aspects that significantly affect the collisional energy loss are examined: the role of fluctuations, and the effect of introducing a running QCD coupling as opposed to the fixed alpha_s=0.3 used previously.

  5. Measurement and modeling of the Saharan dust radiative impact: Overview of the Saharan Dust Experiment (SHADE)

    E-Print Network [OSTI]

    Highwood, Ellie

    on Climate Change (IPCC), 2001]. Among the different aerosol types, mineral dust is one of the major to their scattering and absorbing properties that affect the solar radiation, they also perturb the terrestrial but they still represent one of the largest uncer- tainties in climate change studies [Intergovernmental Panel

  6. Rigollier C., Bauer O., Wald L., 2000. On the clear sky model of the 4th European Solar Radiation Atlas with respect to the Heliosat method. Solar Energy, 68(1), 33-48.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Rigollier C., Bauer O., Wald L., 2000. On the clear sky model of the 4th European Solar Radiation Paris - Armines 1 ON THE CLEAR SKY MODEL OF THE ESRA - EUROPEAN SOLAR RADIATION ATLAS WITH RESPECT, which has been developed in the framework of the new digital European Solar Radiation Atlas (ESRA

  7. A physical model of the photo- and radiation-induced degradation of ytterbium-doped silica optical fibres

    SciTech Connect (OSTI)

    Mady, Franck, E-mail: franck.mady@unice.fr; Duchez, Jean-Bernard, E-mail: franck.mady@unice.fr; Mebrouk, Yasmine, E-mail: franck.mady@unice.fr; Benabdesselam, Mourad, E-mail: franck.mady@unice.fr [University of Nice Sophia Antipolis, Laboratoire de Physique de la Matière Condensée (LPMC), CNRS UMR 7336, Parc Valrose, 06108 Nice cedex 2 (France)

    2014-10-21T23:59:59.000Z

    We propose a model to describe the photo- or/and the radiation-induced darkening of ytterbium-doped silica optical fibers. This model accounts for the well-established experimental features of photo-darkening. Degradation behaviors predicted for fibers pumped in harsh environments are also fully confirmed by experimental data reported in the work by Duchez et al. (this proceeding), which gives a detailed characterization of the interplay between the effects of the pump and those of a superimposed ionizing irradiation (actual operation conditions in space-based applications for instance). In particular, dependences of the darkening build-up on the pump power, the total ionizing dose and the dose rate are all correctly reproduced. The presented model is a ‘sufficient’ one, including the minimal physical ingredients required to reproduce experimental features. Refinements could be proposed to improve, e.g., quantitative kinetics.

  8. A global model simulation for 3-D radiative transfer impact on surface hydrology over the Sierra Nevada and Rocky Mountains

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

    Lee, W.-L.; Gu, Y.; Liou, K. N.; Leung, L. R.; Hsu, H.-H.

    2015-01-01T23:59:59.000Z

    We investigate 3-D mountain effects on solar flux distributions and their impact on surface hydrology over the western United States, specifically the Rocky Mountains and the Sierra Nevada, using the global CCSM4 (Community Climate System Model version 4; Community Atmosphere Model/Community Land Model – CAM4/CLM4) with a 0.23° × 0.31° resolution for simulations over 6 years. In a 3-D radiative transfer parameterization, we have updated surface topography data from a resolution of 1 km to 90 m to improve parameterization accuracy. In addition, we have also modified the upward-flux deviation (3-D–PP (plane-parallel)) adjustment to ensure that the energy balance atmore »the surface is conserved in global climate simulations based on 3-D radiation parameterization. We show that deviations in the net surface fluxes are not only affected by 3-D mountains but also influenced by feedbacks of cloud and snow in association with the long-term simulations. Deviations in sensible heat and surface temperature generally follow the patterns of net surface solar flux. The monthly snow water equivalent (SWE) deviations show an increase in lower elevations due to reduced snowmelt, leading to a reduction in cumulative runoff. Over higher-elevation areas, negative SWE deviations are found because of increased solar radiation available at the surface. Simulated precipitation increases for lower elevations, while it decreases for higher elevations, with a minimum in April. Liquid runoff significantly decreases at higher elevations after April due to reduced SWE and precipitation.« less

  9. A global model simulation for 3-D radiative transfer impact on surface hydrology over Sierra Nevada and Rocky Mountains

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

    Lee, W.-L.; Gu, Y.; Liou, K. N.; Leung, L. R.; Hsu, H.-H.

    2014-01-01T23:59:59.000Z

    We investigate 3-D mountain effects on solar flux distributions and their impact on surface hydrology over the Western United States, specifically the Rocky Mountains and Sierra Nevada using CCSM4 (CAM4/CLM4) global model with a 0.23° × 0.31° resolution for simulations over 6 years. In 3-D radiative transfer parameterization, we have updated surface topography data from a resolution of 1 km to 90 m to improve parameterization accuracy. In addition, we have also modified the upward-flux deviation [3-D ? PP (plane-parallel)] adjustment to ensure that energy balance at the surface is conserved in global climate simulations based on 3-D radiation parameterization.more »We show that deviations of the net surface fluxes are not only affected by 3-D mountains, but also influenced by feedbacks of cloud and snow in association with the long-term simulations. Deviations in sensible heat and surface temperature generally follow the patterns of net surface solar flux. The monthly snow water equivalent (SWE) deviations show an increase in lower elevations due to reduced snowmelt, leading to a reduction in cumulative runoff. Over higher elevation areas, negative SWE deviations are found because of increased solar radiation available at the surface. Simulated precipitation increases for lower elevations, while decreases for higher elevations with a minimum in April. Liquid runoff significantly decreases in higher elevations after April due to reduced SWE and precipitation.« less

  10. Calculation of laser induced impulse based on the laser supported detonation wave model with dissociation, ionization and radiation

    SciTech Connect (OSTI)

    Gan, Li, E-mail: ligan0001@gmail.com; Mousen, Cheng; Xiaokang, Li [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)] [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)

    2014-03-15T23:59:59.000Z

    In the laser intensity range that the laser supported detonation (LSD) wave can be maintained, dissociation, ionization and radiation take a substantial part of the incidence laser energy. There is little treatment on the phenomenon in the existing models, which brings obvious discrepancies between their predictions and the experiment results. Taking into account the impact of dissociation, ionization and radiation in the conservations of mass, momentum and energy, a modified LSD wave model is developed which fits the experimental data more effectively rather than the existing models. Taking into consideration the pressure decay of the normal and the radial rarefaction, the laser induced impulse that is delivered to the target surface is calculated in the air; and the dependencies of impulse performance on laser intensity, pulse width, ambient pressure and spot size are indicated. The results confirm that the dissociation is the pivotal factor of the appearance of the momentum coupling coefficient extremum. This study focuses on a more thorough understanding of LSD and the interaction between laser and matter.

  11. Comment on "A three-loop radiative neutrino mass model with dark matter" [Phys. Lett. B 741 (2015) 163

    E-Print Network [OSTI]

    Geng, Chao-Qiang; Tsai, Lu-Hsing

    2015-01-01T23:59:59.000Z

    We revisit the calculation of the three-loop diagrams for the radiative neutrino mass generation and consider some relevant constraints on the model recently proposed by L. Jin {\\it et al} [Phys. Lett. B 741 (2015) 163]. We find that the previous approximation is inappropriate due to the neglect of some important contributions, and the benchmark point proposed can neither give rise to enough neutrino masses nor accommodate these additional constraints, such as the validity of the perturbation theory, the electroweak precision measurements, and the neutrinoless double beta decays.

  12. On the electrodynamic model of ultra-relativistic laser-plasma interactions caused by radiation reaction effects

    SciTech Connect (OSTI)

    Bashinov, A. V. [Institute of Applied Physics, Russian Academy of Sciences, 603950 Nizhny Novgorod (Russian Federation)] [Institute of Applied Physics, Russian Academy of Sciences, 603950 Nizhny Novgorod (Russian Federation); Kim, A. V. [Institute of Applied Physics, Russian Academy of Sciences, 603950 Nizhny Novgorod (Russian Federation) [Institute of Applied Physics, Russian Academy of Sciences, 603950 Nizhny Novgorod (Russian Federation); University of Nizhny Novgorod, 603950 Nizhny Novgorod (Russian Federation)

    2013-11-15T23:59:59.000Z

    A simple electrodynamic model is developed to define plasma-field structures in self-consistent ultra-relativistic laser-plasma interactions when the radiation reaction effects come into play. An exact analysis of a circularly polarized laser interacting with plasmas is presented. We define fundamental notions, such as nonlinear dielectric permittivity, ponderomotive and dissipative forces acting in a plasma. Plasma-field structures arising during the ultra-relativisitc interactions are also calculated. Based on these solutions, we show that about 50% of laser energy can be converted into gamma-rays in the optimal conditions of laser-foil interaction.

  13. Observation of Wakefields and Resonances in Coherent Synchrotron Radiation

    E-Print Network [OSTI]

    Billinghurst, B E; Baribeau, C; Batten, T; Dallin, L; May, T E; Vogt, J M; Wurtz, W A; Warnock, R; Bizzizero, D A; Kramer, S

    2015-01-01T23:59:59.000Z

    We report on high resolution measurements of resonances in the spectrum of coherent synchrotron radiation (CSR) at the Canadian Light Source (CLS). The resonances permeate the spectrum at wavenumber intervals of $0.074 ~\\textrm{cm}^{-1}$, and are highly stable under changes in the machine setup (energy, bucket filling pattern, CSR in bursting or continuous mode). Analogous resonances were predicted long ago in an idealized theory as eigenmodes of a smooth toroidal vacuum chamber driven by a bunched beam moving on a circular orbit. A corollary of peaks in the spectrum is the presence of pulses in the wakefield of the bunch at well defined spatial intervals. Through experiments and further calculations we elucidate the resonance and wakefield mechanisms in the CLS vacuum chamber, which has a fluted form much different from a smooth torus. The wakefield is observed directly in the 30-110 GHz range by RF diodes, and indirectly by an interferometer in the THz range. The wake pulse sequence found by diodes is less ...

  14. A new algorithm for modelling photoionising radiation in smoothed particle hydrodynamics

    E-Print Network [OSTI]

    James Dale; Barbara Ercolano; Cathie Clarke

    2007-05-23T23:59:59.000Z

    We present a new fast algorithm which allows the simulation of ionising radiation emitted from point sources to be included in high-resolution three-dimensional smoothed particle hydrodynamics simulations of star cluster formation. We employ a Str\\"omgren volume technique in which we use the densities of particles near the line-of-sight between the source and a given target particle to locate the ionisation front in the direction of the target. Along with one--dimensional tests, we present fully three--dimensional comparisons of our code with the three--dimensional Monte-Carlo radiative transfer code, MOCASSIN, and show that we achieve good agreement, even in the case of highly complex density fields.

  15. Millimeter radiation from a 3D model of the solar atmosphere I. Diagnosing chromospheric thermal structure

    E-Print Network [OSTI]

    Loukitcheva, Maria; Carlsson, Mats; White, Stephen

    2015-01-01T23:59:59.000Z

    Aims. We use advanced 3D NLTE radiative magnetohydrodynamic simulations of the solar atmosphere to carry out detailed tests of chromospheric diagnostics at millimeter and submillimeter wavelengths. Methods. We focused on the diagnostics of the thermal structure of the chromosphere in the wavelength bands from 0.4 mm up to 9.6 mm that can be accessed with the Atacama Large Millimeter/Submillimeter Array (ALMA) and investigated how these diagnostics are affected by the instrumental resolution. Results. We find that the formation height range of the millimeter radiation depends on the location in the simulation domain and is related to the underlying magnetic structure. Nonetheless, the brightness temperature is a reasonable measure of the gas temperature at the effective formation height at a given location on the solar surface. There is considerable scatter in this relationship, but this is significantly reduced when very weak magnetic fields are avoided. Our results indicate that although instrumental smearin...

  16. SU-C-12A-03: The Impact of Contrast Medium On Radiation Dose in CT: A Systematic Evaluation Across 58 Patient Models

    SciTech Connect (OSTI)

    Sahbaee, P [NC State University, Raleigh, NC (United States); Samei, E [Duke University Medical Center, Durham, NC (United States); Segars, W [Duke University, Durham, NC (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To assess the effect of contrast medium on radiation dose as a function of time via Monte Carlo simulation from the liver CT scan across a library of 5D XCAT models Methods: A validated Monte Carlo simulation package (PENELOPE) was employed to model a CT system (LightSpeed 64 VCT, GE Healthcare). The radiation dose was estimated from a common abdomen CT examination. The dose estimation was performed on a library of adult extended cardiac-torso (5D XCAT) phantoms (35 male, 23 female, mean age 51.5 years, mean weight 80.2 kg). The 5D XCAT models were created based on patient-specific iodine concentration-time results from our computational contrast medium propagation model for different intravenous injection protocols. To enable a dynamic estimation of radiation dose, each organ in the model was assigned to its own time-concentration curve via the PENELOPE package, material.exe. Using the Monte Carlo, for each scan time point after the injection, 80 million photons were initiated and tracked through the phantoms. Finally, the dose to the liver was tallied from the deposited energy. Results: Monte Carlo simulation results of radiation dose delivered to the liver from the XCAT models indicated up to 30% increase in dose for different time after the administration of contrast medium. Conclusion: The contrast enhancement is employed in over 60% of imaging modalities, which not only remarkably affects the CT image quality, but also increases the radiation dose by as much as 70%. The postinjection multiple acquisition in several enhanced CT protocols, makes the radiation dose increment through the use of contrast medium, an inevitable factor in optimization of these protocols. The relationship between radiation dose and injected contrast medium as a function of time studied in this work allows optimization of contrast administration for vulnerable individuals.

  17. LANL* V1.0: a radiation belt drift shell model suitable for real-time and reanalysis applications

    SciTech Connect (OSTI)

    Koller, Josep [Los Alamos National Laboratory; Reeves, Geoffrey D [Los Alamos National Laboratory; Friedel, Reiner H W [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    Space weather modeling, forecasts, and predictions, especially for the radiation belts in the inner magnetosphere, require detailed information about the Earth's magnetic field. Results depend on the magnetic field model and the L* (pron. L-star) values which are used to describe particle drift shells. Space wather models require integrating particle motions along trajectories that encircle the Earth. Numerical integration typically takes on the order of 10{sup 5} calls to a magnetic field model which makes the L* calculations very slow, in particular when using a dynamic and more accurate magnetic field model. Researchers currently tend to pick simplistic models over more accurate ones but also risking large inaccuracies and even wrong conclusions. For example, magnetic field models affect the calculation of electron phase space density by applying adiabatic invariants including the drift shell value L*. We present here a new method using a surrogate model based on a neural network technique to replace the time consuming L* calculations made with modern magnetic field models. The advantage of surrogate models (or meta-models) is that they can compute the same output in a fraction of the time while adding only a marginal error. Our drift shell model LANL* (Los Alamos National Lab L-star) is based on L* calculation using the TSK03 model. The surrogate model has currently been tested and validated only for geosynchronous regions but the method is generally applicable to any satellite orbit. Computations with the new model are several million times faster compared to the standard integration method while adding less than 1% error. Currently, real-time applications for forecasting and even nowcasting inner magnetospheric space weather is limited partly due to the long computing time of accurate L* values. Without them, real-time applications are limited in accuracy. Reanalysis application of past conditions in the inner magnetosphere are used to understand physical processes and their effect. Without sufficiently accurate L* values, the interpretation of reanalysis results becomes difficult and uncertain. However, with a method that can calculate accurate L* values orders of magnitude faster, analyzing whole solar cycles worth of data suddenly becomes feasible.

  18. Effect of Fractionation in Stereotactic Body Radiation Therapy Using the Linear Quadratic Model

    SciTech Connect (OSTI)

    Yang, Jun, E-mail: JunBME@yahoo.com [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States) [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States); Philadelphia Cyberknife, Havertown, Pennsylvania (United States); Lamond, John [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States) [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States); Philadelphia Cyberknife, Havertown, Pennsylvania (United States); Fowler, Jack [Department of Radiation Oncology, University of Wisconsin, Madison, Wisconsin (United States)] [Department of Radiation Oncology, University of Wisconsin, Madison, Wisconsin (United States); Lanciano, Rachelle [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States) [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States); Philadelphia Cyberknife, Havertown, Pennsylvania (United States); Feng, Jing [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States); Brady, Luther [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States) [Department of Radiation Oncology, Drexel University, Philadelphia, Pennsylvania (United States); Philadelphia Cyberknife, Havertown, Pennsylvania (United States)

    2013-05-01T23:59:59.000Z

    Purpose: To examine the fractionation effect of stereotactic body radiation therapy with a heterogeneous dose distribution. Methods: Derived from the linear quadratic formula with measurements from a hypothetical 2-cm radiosurgical tumor, the threshold percentage was defined as (?/?{sub tissue}/?/?{sub tumor}), the balance ?/? ratio was defined as (prescription dose/tissue tolerance*?/?{sub tumor}), and the balance dose was defined as (tissue tolerance/threshold percentage). Results: With increasing fractions and equivalent peripheral dose to the target, the biological equivalent dose of “hot spots” in a target decreases. The relative biological equivalent doses of serial organs decrease only when the relative percentage of its dose to the prescription dose is above the threshold percentage. The volume of parallel organs at risk decreases only when the tumor's ?/? ratio is above the balance ?/? ratio and the prescription dose is lower than balance dose. Conclusions: The potential benefits of fractionation in stereotactic body radiation therapy depend on the complex interplay between the total dose, ?/? ratios, and dose differences between the target and the surrounding normal tissues.

  19. Radiative decay of excitons in model aggregates of {pi}-conjugated oligomers

    SciTech Connect (OSTI)

    Manas, E.S.; Spano, F.C.

    1998-07-01T23:59:59.000Z

    Spontaneous emission from exciton states in an aggregate of {pi}-conjugated oligomers is studied theoretically. Each oligomer is taken as a ring of N carbon atoms and is treated using a PPP Hamiltonian. Coulombic interactions between rings are treated to first order. The radiative decay rate {gamma} from an exciton state in an aggregate of M aligned oligomers is superradiant, being M times faster than the decay rate of an isolated oligomer exciton. Inter-oligomer interactions have little effect on the exciton size and energy when the oligomer size N is large compared to the interoligomer spacing. However, when N is small, both the exciton size and energy are strongly affected by these interactions, leading to a markedly different N dependence for {gamma}.

  20. he Impact of Primary Marine Aerosol on Atmospheric Chemistry, Radiation and Climate: A CCSM Model Development Study

    SciTech Connect (OSTI)

    Keene, William C. [University of Virginia] [University of Virginia; Long, Michael S. [University of Virginia] [University of Virginia

    2013-05-20T23:59:59.000Z

    This project examined the potential large-scale influence of marine aerosol cycling on atmospheric chemistry, physics and radiative transfer. Measurements indicate that the size-dependent generation of marine aerosols by wind waves at the ocean surface and the subsequent production and cycling of halogen-radicals are important but poorly constrained processes that influence climate regionally and globally. A reliable capacity to examine the role of marine aerosol in the global-scale atmospheric system requires that the important size-resolved chemical processes be treated explicitly. But the treatment of multiphase chemistry across the breadth of chemical scenarios encountered throughout the atmosphere is sensitive to the initial conditions and the precision of the solution method. This study examined this sensitivity, constrained it using high-resolution laboratory and field measurements, and deployed it in a coupled chemical-microphysical 3-D atmosphere model. First, laboratory measurements of fresh, unreacted marine aerosol were used to formulate a sea-state based marine aerosol source parameterization that captured the initial organic, inorganic, and physical conditions of the aerosol population. Second, a multiphase chemical mechanism, solved using the Max Planck Institute for Chemistryâ??s MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere) system, was benchmarked across a broad set of observed chemical and physical conditions in the marine atmosphere. Using these results, the mechanism was systematically reduced to maximize computational speed. Finally, the mechanism was coupled to the 3-mode modal aerosol version of the NCAR Community Atmosphere Model (CAM v3.6.33). Decadal-scale simulations with CAM v.3.6.33, were run both with and without reactive-halogen chemistry and with and without explicit treatment of particulate organic carbon in the marine aerosol source function. Simulated results were interpreted (1) to evaluate influences of marine aerosol production on the microphysical properties of aerosol populations and clouds over the ocean and the corresponding direct and indirect effects on radiative transfer; (2) atmospheric burdens of reactive halogen species and their impacts on O3, NOx, OH, DMS, and particulate non-sea-salt SO42-; and (3) the global production and influences of marine-derived particulate organic carbon. The model reproduced major characteristics of the marine aerosol system and demonstrated the potential sensitivity of global, decadal-scale climate metrics to multiphase marine-derived components of Earthâ??s troposphere. Due to the combined computational burden of the coupled system, the currently available computational resources were the limiting factor preventing the adequate statistical analysis of the overall impact that multiphase chemistry might have on climate-scale radiative transfer and climate.

  1. Ab initio Based Modeling of Radiation Effects in Multi-Component Alloys: Final Scientific/Technical Report

    SciTech Connect (OSTI)

    Dane Morgan

    2010-06-10T23:59:59.000Z

    The project began March 13, 2006, allocated for three years, and received a one year extension from March 13, 2009 to March 12, 2010. It has now completed 48 of 48 total months. The project was focused on using ab initio methods to gain insights into radiation induced segregation (RIS) in Ni-Fe-Cr alloys. The project had the following key accomplishments • Development of a large database of ab initio energetics that can be used by many researchers in the future for increased understanding of this system. For example, we have the first calculations showing a dramatic stabilization effect of Cr-Cr interstitial dumbbells in Ni. • Prediction of both vacancy and interstitial diffusion constants for Ni-Cr and Ni-Fe for dilute Cr and Fe. This work included generalization of widely used multifrequency models to make use of ab initio derived energetics and thermodynamics. • Prediction of qualitative trends of RIS from vacancy and interstitial mechanisms, suggesting the two types of defect fluxes drive Cr RIS in opposite directions. • Detailed kinetic Monte Carlo modeling of diffusion by vacancy mechanism in Ni-Cr as a function of Cr concentration. The results demonstrate that Cr content can have a significant effect on RIS. • Development of a quantitative RIS transport model, including models for thermodynamic factors and boundary conditions.

  2. Development of advanced cloud parameterizations to examine air quality, cloud properties, and cloud-radiation feedback in mesoscale models

    SciTech Connect (OSTI)

    Lee, In Young

    1993-09-01T23:59:59.000Z

    The distribution of atmospheric pollutants is governed by dynamic processes that create the general conditions for transport and mixing, by microphysical processes that control the evolution of aerosol and cloud particles, and by chemical processes that transform chemical species and form aerosols. Pollutants emitted into the air can undergo homogeneous gas reactions to create a suitable environment for the production by heterogeneous nucleation of embryos composed of a few molecules. The physicochemical properties of preexisting aerosols interact with newly produced embryos to evolve by heteromolecular diffusion and coagulation. Hygroscopic particles wig serve as effective cloud condensation nuclei (CCN), while hydrophobic particles will serve as effective ice-forming nuclei. Clouds form initially by condensation of water vapor on CCN and evolve in a vapor-liquid-solid system by deposition, sublimation, freezing, melting, coagulation, and breakup. Gases and aerosols that enter the clouds undergo aqueous chemical processes and may acidity hydrometer particles. Calculations for solar and longwave radiation fluxes depend on how the respective spectra are modified by absorbers such as H{sub 2}O, CO{sub 2}, O{sub 3}, CH{sub 4}, N{sub 2}O, chlorofruorocarbons, and aerosols. However, the flux calculations are more complicated for cloudy skies, because the cloud optical properties are not well defined. In this paper, key processes such as tropospheric chemistry, cloud microphysics parameterizations, and radiation schemes are reviewed in terms of physicochemical processes occurring, and recommendations are made for the development of advanced modules applicable to mesoscale models.

  3. Radiation: Radiation Control (Indiana)

    Broader source: Energy.gov [DOE]

    It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...

  4. Geophysical Fluid Dynamics Laboratory general circulation model investigation of the indirect radiative effects

    E-Print Network [OSTI]

    Russell, Lynn

    Geophysical Fluid Dynamics Laboratory general circulation model investigation of the indirect Corporation for Atmospheric Research, Geophysical Fluid Dynamics Laboratory, Princeton, New Jersey, USA V. Ramaswamy, Paul A. Ginoux, and Larry W. Horowitz Geophysical Fluid Dynamics Laboratory, Princeton, New

  5. Mechanism and computational model for Lyman-{alpha}-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

    SciTech Connect (OSTI)

    Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Bakule, Pavel [STFC, ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom); Yokoyama, Koji [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Ishida, Katsuhiko; Iwasaki, Masahiko [Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan)

    2011-09-15T23:59:59.000Z

    We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-{alpha} (Ly-{alpha}) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-{alpha} generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-{alpha} radiation generation can achieve a value of {approx}5x10{sup -4} which is restricted by the total combined absorption of the fundamental and generated radiation.

  6. Modeling of the $\\gamma$-ray pulsed spectra of Geminga, Crab, and Vela with synchro-curvature radiation

    E-Print Network [OSTI]

    Viganò, Daniele

    2015-01-01T23:59:59.000Z

    $\\gamma$-ray spectra of pulsars have been mostly studied in a phenomenological way, by fitting them to a cut-off power-law function. Here, we analyze a model where pulsed emission comes from synchro-curvature processes in a gap. We calculate the variation of kinetic energy of magnetospheric particles along the gap and the associated radiated spectra, considering an effective particle distribution. We fit the phase-averaged and phase-resolved {\\em Fermi}-LAT spectra of the three brightest $\\gamma$-ray pulsars: Geminga, Crab, and Vela, and constrain the three free parameters we leave free in the model. Our best-fit models well reproduce the observed data, apart from residuals above a few GeV in some cases, range for which the inverse Compton scattering likely becomes the dominant mechanism. In any case, the flat slope at low-energy ($\\lesssim$ GeV) seen by {\\it Fermi}-LAT both in the phase-averaged and phase-resolved spectra of most pulsars, including the ones we studied, requires that most of the detected radi...

  7. Chronic graft-versus-host disease in the rat radiation chimera. III. Immunology and immunopathology in rapidly induced models

    SciTech Connect (OSTI)

    Beschorner, W.E.; Tutschka, P.J.; Santos, G.W.

    1983-03-01T23:59:59.000Z

    Although chronic graft-versus-host disease (GVHD) frequently develops in the long-term rat radiation chimera, we present three additional models in which a histologically similar disease is rapidly induced. These include adoptive transfer of spleen and bone marrow from rats with spontaneous chronic GVHD into lethally irradiated rats of the primary host strain; sublethal irradiation of stable chimeras followed by a booster transplant; and transfer of spleen cells of chimeras recovering from acute GVHD into second-party (primary recipient strain) or third-party hosts. Some immunopathologic and immune abnormalities associated with spontaneous chronic GVHD were not observed in one or more of the induced models. Thus, IgM deposition in the skin, antinuclear antibodies, and vasculitis appear to be paraphenomena. On the other hand, lymphoid hypocellularity of the thymic medulla, immaturity of splenic follicles, and nonspecific suppressor cells were consistently present in the long term chimeras, and in all models. These abnormalities therefore may be pathogenetically important, or closely related to the development of chronic GVHD.

  8. A Sensitivity Study on Modeling Black Carbon in Snow and its Radiative Forcing over the Arctic and Northern China

    SciTech Connect (OSTI)

    Qian, Yun; Wang, Hailong; Zhang, Rudong; Flanner, M. G.; Rasch, Philip J.

    2014-06-02T23:59:59.000Z

    Black carbon in snow (BCS) simulated in the Community Atmosphere Model (CAM5) is evaluated against measurements over Northern China and the Arctic, and its sensitivity to atmospheric deposition and two parameters that affect post-depositional enrichment is explored. The BCS concentration is overestimated (underestimated) by a factor of two in Northern China (Arctic) in the default model, but agreement with observations is good over both regions in the simulation with improvements in BC transport and deposition. Sensitivity studies indicate that uncertainty in the melt-water scavenging efficiency (MSE) parameter substantially affects BCS and its radiative forcing (by a factor of 2-7) in the Arctic through post-depositional enrichment. The MSE parameter has a relatively small effect on the magnitude of BCS seasonal cycle but can alter its phase in Northern China. The impact of the snow aging scaling factor (SAF) on BCS, partly through the post-depositional enrichment effect, shows more complex latitudinal and seasonal dependence. Similar to MSE, SAF affects more significantly the magnitude (phase) of BCS season cycle over the Arctic (Northern China). While uncertainty associated with the representation of BC transport and deposition processes in CAM5 is more important than that associated with the two snow model parameters in Northern China, the two uncertainties have comparable effect in the Arctic.

  9. ARM - Campaign Instrument - csr

    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: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearchSOLICITATIONIMODIgovInstrumentsasticryo

  10. Spherical Shell Cosmological Model and Uniformity of Cosmic Microwave Background Radiation

    E-Print Network [OSTI]

    Branislav Vlahovic

    2012-07-06T23:59:59.000Z

    Considered is spherical shell as a model for visible universe and parameters that such model must have to comply with the observable data. The topology of the model requires that motion of all galaxies and light must be confined inside a spherical shell. Consequently the observable universe cannot be defined as a sphere centered on the observer, rather it is an arc length within the volume of the spherical shell. The radius of the shell is 4.46 $\\pm$ 0.06 Gpc, which is for factor $\\pi$ smaller than radius of a corresponding 3-sphere. However the event horizon, defined as the arc length inside the shell, has the size of 14.0 $\\pm$ 0.2 Gpc, which is in agreement with the observable data. The model predicts, without inflation theory, the isotropy and uniformity of the CMB. It predicts the correct value for the Hubble constant $H_0$ = 67.26 $\\pm$ 0.90 km/s/Mpc, the cosmic expansion rate $H(z)$, and the speed of the event horizon in agreement with observations. The theoretical suport for shell model comes from general relativity, curvature of space by mass, and from holographic principle. The model explains the reason for the established discrepancy between the non-covariant version of the holographic principle and the calculated dimensionless entropy $(S/k)$ for the visible universe, which exceeds the entropy of a black hole. The model is in accordance with the distribution of radio sources in space, type Ia data, and data from the Hubble Ultra Deep Field optical and near-infrared survey.

  11. GFDL ARM Project Technical Report: Using ARM Observations to Evaluate Cloud and Convection Parameterizations & Cloud-Convection-Radiation Interactions in the GFDL Atmospheric General Circulation Model

    SciTech Connect (OSTI)

    V. Ramaswamy; L. J. Donner; J-C. Golaz; S. A. Klein

    2010-06-17T23:59:59.000Z

    This report briefly summarizes the progress made by ARM postdoctoral fellow, Yanluan Lin, at GFDL during the period from October 2008 to present. Several ARM datasets have been used for GFDL model evaluation, understanding, and improvement. This includes a new ice fall speed parameterization with riming impact and its test in GFDL AM3, evaluation of model cloud and radiation diurnal and seasonal variation using ARM CMBE data, model ice water content evaluation using ARM cirrus data, and coordination of the TWPICE global model intercomparison. The work illustrates the potential and importance of ARM data for GCM evaluation, understanding, and ultimately, improvement of GCM cloud and radiation parameterizations. Future work includes evaluation and improvement of the new dynamicsPDF cloud scheme and aerosol activation in the GFDL model.

  12. Dark matter and strong electroweak phase transition in a radiative neutrino mass model

    SciTech Connect (OSTI)

    Ahriche, Amine [Department of Physics, University of Jijel, PB 98 Ouled Aissa, DZ-18000 Jijel (Algeria); Nasri, Salah, E-mail: aahriche@ictp.it, E-mail: snasri@uaeu.ac.ae [Physics Department, UAE University, POB 17551, Al Ain (United Arab Emirates)

    2013-07-01T23:59:59.000Z

    We consider an extension of the standard model (SM) with charged singlet scalars and right handed (RH) neutrinos all at the electroweak scale. In this model, the neutrino masses are generated at three loops, which provide an explanation for their smallness, and the lightest RH neutrino, N{sub 1}, is a dark matter candidate. We find that for three generations of RH neutrinos, the model can be consistent with the neutrino oscillation data, lepton flavor violating processes, N{sub 1} can have a relic density in agreement with the recent Planck data, and the electroweak phase transition can be strongly first order. We also show that the charged scalars may enhance the branching ratio h???, where as h??Z get can get few percent suppression. We also discuss the phenomenological implications of the RH neutrinos at the collider.

  13. A revised model for radiation dosimetry in the human gastrointestinal tract 

    E-Print Network [OSTI]

    Bhuiyan, Md. Nasir Uddin

    2004-09-30T23:59:59.000Z

    A new model for an adult human gastrointestinal tract (GIT) has been developed for use in internal dose estimations to the wall of the GIT and to the other organs and tissues of the body from radionuclides deposited in the lumenal contents...

  14. Incorporation of a time-dependent thermodynamic model and a radiation

    E-Print Network [OSTI]

    Salvaggio, Carl

    the phenomenology commonly observed by high-resolution thermal infrared sensors to a point where the model can be used as a research tool to evaluate the limitations in our understanding of the thermal infrared into infrared three-dimensional synthetic image generation John R. Schott, MEMBER SPIE Rolando Raqueno Carl

  15. Using Satellite Ocean Color Data to Derive an Empirical Model for the Penetration Depth of Solar Radiation (Hp) in the Tropical Pacific Ocean

    E-Print Network [OSTI]

    Chen, .Dake

    Radiation (Hp) in the Tropical Pacific Ocean RONG-HUA ZHANG State Key Laboratory of Satellite OceanUsing Satellite Ocean Color Data to Derive an Empirical Model for the Penetration Depth of Solar Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, Hangzhou, Zhejiang

  16. Pulsed Versus Conventional Radiation Therapy in Combination With Temozolomide in a Murine Orthotopic Model of Glioblastoma Multiforme

    SciTech Connect (OSTI)

    Lee, David Y.; Chunta, John L.; Park, Sean S.; Huang, Jiayi; Martinez, Alvaro A.; Grills, Inga S.; Krueger, Sarah A.; Wilson, George D. [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Marples, Brian, E-mail: brian.marples@beaumont.edu [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States)

    2013-08-01T23:59:59.000Z

    Purpose: To evaluate the efficacy of pulsed low-dose radiation therapy (PLRT) combined with temozolomide (TMZ) as a novel treatment approach for radioresistant glioblastoma multiforme (GBM) in a murine model. Methods and Materials: Orthotopic U87MG hGBM tumors were established in Nu-Foxn1{sup nu} mice and imaged weekly using a small-animal micropositron emission tomography (PET)/computed tomography (CT) system. Tumor volume was determined from contrast-enhanced microCT images and tumor metabolic activity (SUVmax) from the F18-FDG microPET scan. Tumors were irradiated 7 to 10 days after implantation with a total dose of 14 Gy in 7 consecutive days. The daily treatment was given as a single continuous 2-Gy dose (RT) or 10 pulses of 0.2 Gy using an interpulse interval of 3 minutes (PLRT). TMZ (10 mg/kg) was given daily by oral gavage 1 hour before RT. Tumor vascularity and normal brain damage were assessed by immunohistochemistry. Results: Radiation therapy with TMZ resulted in a significant 3- to 4-week tumor growth delay compared with controls, with PLRT+TMZ the most effective. PLRT+TMZ resulted in a larger decline in SUVmax than RT+TMZ. Significant differences in survival were evident. Treatment after PLRT+TMZ was associated with increased vascularization compared with RT+TMZ. Significantly fewer degenerating neurons were seen in normal brain after PLRT+TMZ compared with RT+TMZ. Conclusions: PLRT+TMZ produced superior tumor growth delay and less normal brain damage when compared with RT+TMZ. The differential effect of PLRT on vascularization may confirm new treatment avenues for GBM.

  17. ORBITAL MIGRATION OF LOW-MASS PLANETS IN EVOLUTIONARY RADIATIVE MODELS: AVOIDING CATASTROPHIC INFALL

    SciTech Connect (OSTI)

    Lyra, Wladimir; Mac Low, Mordecai-Mark [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024 (United States); Paardekooper, Sijme-Jan, E-mail: wlyra@amnh.or, E-mail: mordecai@amnh.or [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 OWA (United Kingdom)

    2010-06-01T23:59:59.000Z

    Outward migration of low-mass planets has recently been shown to be a possibility in non-barotropic disks. We examine the consequences of this result in evolutionary models of protoplanetary disks. Planet migration occurs toward equilibrium radii with zero torque. These radii themselves migrate inwards because of viscous accretion and photoevaporation. We show that as the surface density and temperature fall the planet orbital migration and disk depletion timescales eventually become comparable, with the precise timing depending on the mass of the planet. When this occurs, the planet decouples from the equilibrium radius. At this time, however, the gas surface density is already too low to drive substantial further migration. A higher mass planet, of 10 M {sub +}, can open a gap during the late evolution of the disk, and stops migrating. Low-mass planets, with 1 or 0.1 M {sub +}, released beyond 1 AU in our models avoid migrating into the star. Our results provide support for the reduced migration rates adopted in recent planet population synthesis models.

  18. Testable two-loop radiative neutrino mass model based on an $LLQd^cQd^c$ effective operator

    E-Print Network [OSTI]

    Paul W. Angel; Yi Cai; Nicholas L. Rodd; Michael A. Schmidt; Raymond R. Volkas

    2014-10-03T23:59:59.000Z

    A new two-loop radiative Majorana neutrino mass model is constructed from the gauge-invariant effective operator $L^i L^j Q^k d^c Q^l d^c \\epsilon_{ik} \\epsilon_{jl}$ that violates lepton number conservation by two units. The ultraviolet completion features two scalar leptoquark flavors and a color-octet Majorana fermion. We show that there exists a region of parameter space where the neutrino oscillation data can be fitted while simultaneously meeting flavor-violation and collider bounds. The model is testable through lepton flavor-violating processes such as ${\\mu} \\to e{\\gamma}$, $\\mu \\to eee$, and $\\mu N \\to eN$ conversion, as well as collider searches for the scalar leptoquarks and color-octet fermion. We computed and compiled a list of necessary Passarino-Veltman integrals up to boxes in the approximation of vanishing external momenta and made them available as a Mathematica package, denoted as ANT.

  19. Health effects models for nuclear power plant accident consequence analysis: Modifications of models resulting from recent reports on health effects of ionizing radiation

    SciTech Connect (OSTI)

    Abrahamson, S. (Wisconsin Univ., Madison, WI (United States)); Bender, M.A. (Brookhaven National Lab., Upton, NY (United States)); Boecker, B.B.; Scott, B.R. (Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States). Inhalation Toxicology Research Inst.); Gilbert, E.S. (Pacific Northwest Lab., Richland, WA (United States))

    1991-08-01T23:59:59.000Z

    The Nuclear Regulatory Commission has sponsored several studies to identify and quantify the potential health effects of accidental releases of radionuclides from nuclear power plants. The most recent health effects models resulting from these efforts were published in two reports, NUREG/CR-4214, Rev. 1, Part 1 (1990) and Part 2 (1989). Several major health effects reports have been published recently that may impact the health effects models presented in these reports. This addendum to the Part 2 (1989) report, provides a review of the 1986 and 1988 reports by the United Nations Scientific Committee on the Effects of Atomic Radiation, the National Academy of Sciences/National Research Council BEAR 5 Committee report and Publication 60 of the International Commission on Radiological Protection as they relate to this report. The three main sections of this addendum discuss early occurring and continuing effects, late somatic effects, and genetic effects. The major changes to the NUREG/CR-4214 health effects models recommended in this addendum are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies like that on the Japanese A-bomb survivors. The results presented in this addendum should be used with the basic NUREG/CR-4214 reports listed above to obtain the most recent views on the potential health effects of radionuclides released accidentally from nuclear power plants. 48 refs., 4 figs., 24 tabs.

  20. A preliminary model of the circulating blood for use in radiation dose calculations

    E-Print Network [OSTI]

    Hui, Tsz-Yik Edmond

    1986-01-01T23:59:59.000Z

    of Advisory Committee: Dr. John W. Poston Currently, there is a need for a dosimetric model to describe the circulatory system in an adult human. This need exists because of the increasing number of radiopharmaceuticals used in nuclear medicine which... Administered Activity for Indium-113m-labeled Blood Platelets for Selected Organs biological data on blood volume and distribution in the circulatory system (A163, Ba61, Co71, Fo71, Sm84, Mc74) . Only major organs that contain large amounts of blood were...

  1. Modeling heat conduction and radiation transport with the diffusion equation in

    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: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA /Ml'. William Hirst HirstModelingAssessing theheat

  2. Working Group Reports Calibration of Radiation Codes Used in Climate Models:

    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 SpinPrincetonUsingWhat is abigpresented in theWorkBusiness1: Model4:97

  3. The Gottingen Minipig Is a Model of the Hematopoietic Acute Radiation Syndrome: G-Colony Stimulating Factor Stimulates Hematopoiesis and Enhances Survival From Lethal Total-Body ?-Irradiation

    SciTech Connect (OSTI)

    Moroni, Maria, E-mail: maria.moroni@usuhs.edu [Radiation Countermeasures Program, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Ngudiankama, Barbara F. [Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland (United States); Christensen, Christine [Division of Comparative Pathology, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Olsen, Cara H. [Biostatistics Consulting Center, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Owens, Rossitsa [Radiation Countermeasures Program, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Lombardini, Eric D. [Veterinary Medicine Department, Armed Forces Research Institute of Medical Sciences, Bangkok (Thailand); Holt, Rebecca K. [Veterinary Science Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Whitnall, Mark H. [Radiation Countermeasures Program, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States)

    2013-08-01T23:59:59.000Z

    Purpose: We are characterizing the Gottingen minipig as an additional large animal model for advanced drug testing for the acute radiation syndrome (ARS) to enhance the discovery and development of novel radiation countermeasures. Among the advantages provided by this model, the similarities to human hematologic parameters and dynamics of cell loss/recovery after irradiation provide a convenient means to compare the efficacy of drugs known to affect bone marrow cellularity and hematopoiesis. Methods and Materials: Male Gottingen minipigs, 4 to 5 months old and weighing 9 to 11 kg, were used for this study. We tested the standard off-label treatment for ARS, rhG-CSF (Neupogen, 10 ?g/kg/day for 17 days), at the estimated LD70/30 total-body ?-irradiation (TBI) radiation dose for the hematopoietic syndrome, starting 24 hours after irradiation. Results: The results indicated that granulocyte colony stimulating factor (G-CSF) enhanced survival, stimulated recovery from neutropenia, and induced mobilization of hematopoietic progenitor cells. In addition, the administration of G-CSF resulted in maturation of monocytes/macrophages. Conclusions: These results support continuing efforts toward validation of the minipig as a large animal model for advanced testing of radiation countermeasures and characterization of the pathophysiology of ARS, and they suggest that the efficacy of G-CSF in improving survival after total body irradiation may involve mechanisms other than increasing the numbers of circulating granulocytes.

  4. ORBITAL MIGRATION OF INTERACTING LOW-MASS PLANETS IN EVOLUTIONARY RADIATIVE TURBULENT MODELS

    SciTech Connect (OSTI)

    Horn, Brandon; Mac Low, Mordecai-Mark [Department of Astronomy, Columbia University, 550 West 120th St, New York, NY 10027 (United States); Lyra, Wladimir [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024 (United States); Sandor, Zsolt, E-mail: bhorn@astro.columbia.edu, E-mail: wlyra@amnh.org, E-mail: mordecai@amnh.org, E-mail: zsolt.sandor@uibk.ac.at [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, 69117, Heidelberg (Germany)

    2012-05-01T23:59:59.000Z

    The torques exerted by a locally isothermal disk on an embedded planet lead to rapid inward migration. Recent work has shown that modeling the thermodynamics without the assumption of local isothermality reveals regions where the net torque on an embedded planet is positive, leading to outward migration of the planet. When a region with negative torque lies directly exterior to this, planets in the inner region migrate outward and planets in the outer region migrate inward, converging where the torque is zero. We incorporate the torques from an evolving non-isothermal disk into an N-body simulation to examine the behavior of planets or planetary embryos interacting in the convergence zone. We find that mutual interactions do not eject objects from the convergence zone. Small numbers of objects in a laminar disk settle into near resonant orbits that remain stable over the 10 Myr periods that we examine. However, either or both increasing the number of planets or including a correlated, stochastic force to represent turbulence drives orbit crossings and mergers in the convergence zone. These processes can build gas giant cores with masses of order 10 Earth masses from sub-Earth mass embryos in 2-3 Myr.

  5. On the evolution of the momentarily static radiation free data in the Apostolatos - Thorne cylindrical shell model

    E-Print Network [OSTI]

    Reinaldo J. Gleiser; Daniel E. Barraco

    2013-08-28T23:59:59.000Z

    We study the evolution of the "Momentarily Static and Radiation Free" (MSRF) initial data for the Apostolatos - Thorne cylindrical shell model. We analyze the relation between the parameters characterizing the MSRF data those for the corresponding final static configuration, and show that there is a priori no conflict for any choice of initial MSRF data, in contrast with some recent results of Nakao, Ida and Kurita. We also consider the problem in the linear approximation, and show that the evolution is stable in all cases. We find that the approach to the final state is very slow, with an inverse logarithmic dependence on time at fixed radius. To complement these results we introduce a numerical computation procedure that allows us to visualize the explicit form of the evolution of the shell and of the gravitational field up to large times. The results are in agreement with the qualitative behaviour conjectured by Apostolatos and Thorne, with an initial damped oscillatory stage, but with oscillations about a position that approaches slowly that of the static final state, as indicated by our analysis. We also include an Appendix, where we prove the existence of solutions of the cylindrical wave equation with vanishing initial value for $r > R_0$, ($R_0 > 0$ some finite constant), that approach a constant value for large times. This result is crucial for the proof of compatibility of arbitrary MSRF initial data and a final static configuration for the system.

  6. Numerical modeling of radiation-dominated and quantum-electrodynamically strong regimes of laser-plasma interaction

    SciTech Connect (OSTI)

    Sokolov, Igor V. [Space Physics Research Laboratory, University of Michigan, Ann Arbor, Michigan 48109 (United States); Naumova, Natalia M. [Laboratoire d'Optique Appliquee, UMR 7639 ENSTA, Ecole Polytechnique, CNRS, 91761 Palaiseau (France); Nees, John A. [Center for Ultrafast Optical Science and FOCUS Center, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2011-09-15T23:59:59.000Z

    Ultra-strong laser pulses can be so intense that an electron in the focused beam loses significant energy due to {gamma}-photon emission while its motion deviates via the radiation back-reaction. Numerical methods and tools designed to simulate radiation-dominated and quantum-electrodynamically strong laser-plasma interactions are summarized here.

  7. EPOXYEICOSATRIENOIC ACIDS (EET) ANALOG, EET-A REDUCED RENAL INJURY IN A RAT MODEL OF RADIATION NEPHROPATHY

    E-Print Network [OSTI]

    OF RADIATION NEPHROPATHY *Supported by a grant from NIH (T35 HL072483) and this study is supported by a grant pressure *PRadiation + Vehicle #PRadiation nephropathy occurs after to treat cancer, and after accidental or combative radiation exposure. It presents clinically as azotemia

  8. Carbonaceous aerosols recorded in a southeastern Tibetan glacier: analysis of temporal variations and model estimates of sources and radiative forcing

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

    Wang, Mo; Xu, B.; Cao, J.; Tie, X.; Wang, Hailong; Zhang, Rudong; Qian, Yun; Rasch, Philip J.; Zhao, Shuyu; Wu, Guangjian; et al

    2015-01-01T23:59:59.000Z

    High temporal resolution measurements of black carbon (BC) and organic carbon (OC) covering the time period of 1956–2006 in an ice core over the southeastern Tibetan Plateau show a distinct seasonal dependence of BC and OC with higher respective concentrations but a lower OC / BC ratio in the non-monsoon season than during the summer monsoon. We use a global aerosol-climate model, in which BC emitted from different source regions can be explicitly tracked, to quantify BC source–receptor relationships between four Asian source regions and the southeastern Tibetan Plateau as a receptor. The model results show that South Asia hasmore »the largest contribution to the present-day (1996–2005) mean BC deposition at the ice-core drilling site during the non-monsoon season (October to May) (81%) and all year round (74%), followed by East Asia (14% to the non-monsoon mean and 21% to the annual mean). The ice-core record also indicates stable and relatively low BC and OC deposition fluxes from the late 1950s to 1980, followed by an overall increase to recent years. This trend is consistent with the BC and OC emission inventories and the fuel consumption of South Asia (as the primary contributor to annual mean BC deposition). Moreover, the increasing trend of the OC / BC ratio since the early 1990s indicates a growing contribution of coal combustion and/or biomass burning to the emissions. The estimated radiative forcing induced by BC and OC impurities in snow has increased since 1980, suggesting an increasing potential influence of carbonaceous aerosols on the Tibetan glacier melting and the availability of water resources in the surrounding regions. Our study indicates that more attention to OC is merited because of its non-negligible light absorption and the recent rapid increases evident in the ice-core record.« less

  9. Primate polonium metabolic models and their use in estimation of systemic radiation doses from bioassay data. Final report

    SciTech Connect (OSTI)

    Cohen, N. [New York Univ. Medical Center, Tuxedo, NY (United States). Dept. of Environmental Medicine

    1989-03-15T23:59:59.000Z

    A Polonium metabolic model was derived and incorporated into a Fortran algorithm which estimates the systemic radiation dose from {sup 210}Po when applied to occupational urine bioassay data. The significance of the doses estimated are examined by defining the degree of uncertainty attached to them through comprehensive statistical testing procedures. Many parameters necessary for dosimetry calculations (such as organ partition coefficients and excretion fractions), were evaluated from metabolic studies of {sup 210}Po in non-human primates. Two tamarins and six baboons were injected intravenously with {sup 210}Po citrate. Excreta and blood samples were collected. Five of the baboons were sacrificed at times ranging from 1 day to 3 months post exposure. Complete necropsies were performed and all excreta and the majority of all skeletal and tissue samples were analyzed radiochemically for their {sup 210}Po content. The {sup 210}Po excretion rate in the baboon was more rapid than in the tamarin. The biological half-time of {sup 210}Po excretion in the baboon was approximately 15 days while in the tamarin, the {sup 210}Po excretion rate was in close agreement with the 50 day biological half-time predicted by ICRP 30. Excretion fractions of {sup 210}Po in the non-human primates were found to be markedly different from data reported elsewhere in other species, including man. A thorough review of the Po urinalysis procedure showed that significant recovery losses resulted when metabolized {sup 210}Po was deposited out of raw urine. Polonium-210 was found throughout the soft tissues of the baboon but not with the partition coefficients for liver, kidneys, and spleen that are predicted by the ICRP 30 metabolic model. A fractional distribution of 0.29 for liver, 0.07 for kidneys, and 0.006 for spleen was determined. Retention times for {sup 210}Po in tissues are described by single exponential functions with biological half-times ranging from 15 to 50 days.

  10. Carbonaceous Aerosols Recorded in a Southeastern Tibetan Glacier: Analysis of Temporal Variations and Model Estimates of Sources and Radiative Forcing

    SciTech Connect (OSTI)

    Wang, Mo; Xu, B.; Cao, J.; Tie, X.; Wang, Hailong; Zhang, Rudong; Qian, Yun; Rasch, Philip J.; Zhao, Shuyu; Wu, Guangjian; Zhao, Huabiao; Joswiak, Daniel R.; Li, Jiule; Xie, Ying

    2015-01-01T23:59:59.000Z

    High temporal resolution measurements of black carbon (BC) and organic carbon (OC) covering the time period of 1956-2006 in an ice core over the southeastern Tibetan Plateau show a distinct seasonal dependence of OC/BC ratio with higher values in the non-monsoon season than during the summer monsoon. We use a global aerosol-climate model, in which BC emitted from different source regions can be explicitly tracked, to quantify BC source-receptor relationships between four Asian source regions and the southern Tibetan Plateau as a receptor. The model results show that South Asia is a primary contributor during the non-monsoon season (October to May) (81%) and on an annual basis (74%), followed by East Asia (14% and 21%, respectively). The ice-core record also indicates stable and relatively low BC and OC deposition fluxes from late 1950s to 1980, followed by an overall increase to recent years. This trend is consistent with the BC and OC emission inventories and the fuel consumption of South Asia as the primary contributor. Moreover, the increasing trend of OC/BC ratio since the early 1990s indicates a growing contribution of coal combustion and biomass burning to the emissions. The estimated radiative forcing induced by BC/OC impurities in snow has increased since 1980, suggesting an increasing influence of carbonaceous aerosols on the Tibetan glacier melting, influencing the availability of water resources in the surrounding regions. Our study indicates that the role of OC deserves more attention because of its non-negligible light absorption and the more rapid increase than BC

  11. Atomistic modeling of intrinsic and radiation-enhanced fission gas (Xe) diffusion in UO2 +/- x: Implications for nuclear fuel performance modeling

    SciTech Connect (OSTI)

    Giovanni Pastore; Michael R. Tonks; Derek R. Gaston; Richard L. Williamson; David Andrs; Richard Martineau

    2014-03-01T23:59:59.000Z

    Based on density functional theory (DFT) and empirical potential calculations, the diffusivity of fission gas atoms (Xe) in UO2 nuclear fuel has been calculated for a range of non-stoichiometry (i.e. UO2x), under both out-of-pile (no irradiation) and in-pile (irradiation) conditions. This was achieved by first deriving expressions for the activation energy that account for the type of trap site that the fission gas atoms occupy, which includes the corresponding type of mobile cluster, the charge state of these defects and the chemistry acting as boundary condition. In the next step DFT calculations were used to estimate migration barriers and internal energy contributions to the thermodynamic properties and calculations based on empirical potentials were used to estimate defect formation and migration entropies (i.e. pre-exponentials). The diffusivities calculated for out-of-pile conditions as function of the UO2x nonstoichiometrywere used to validate the accuracy of the diffusion models and the DFT calculations against available experimental data. The Xe diffusivity is predicted to depend strongly on the UO2x non-stoichiometry due to a combination of changes in the preferred Xe trap site and in the concentration of uranium vacancies enabling Xe diffusion, which is consistent with experiments. After establishing the validity of the modeling approach, it was used for studying Xe diffusion under in-pile conditions, for which experimental data is very scarce. The radiation-enhanced Xe diffusivity is compared to existing empirical models. Finally, the predicted fission gas diffusion rates were implemented in the BISON fuel performance code and fission gas release from a Risø fuel rod irradiation experiment was simulated. 2014 Elsevier B.V. All rights

  12. Danger radiations

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    Le conférencier Mons.Hofert parle des dangers et risques des radiations, le contrôle des zones et les précautions à prendre ( p.ex. film badge), comment mesurer les radiations etc.

  13. Radiation Reaction in Quantum Vacuum

    E-Print Network [OSTI]

    Keita Seto

    2014-11-02T23:59:59.000Z

    From the development of the electron theory by H. A. Lorentz in 1906, many authors have tried to reformulate this model named "radiation reaction". P. A. M. Dirac derived the relativistic-classical electron model in 1938, which is now called the Lorentz-Abraham-Dirac model. But this model has the big difficulty of the run-away solution. Recently, this equation has become important for ultra-intense laser-electron (plasma) interactions. Therefore, it is desirable to stabilize this model of the radiation reaction for estimations. Via my recent research, I found a stabilized model of radiation reaction in quantum vacuum. This leads us to an updated Fletcher-Millikan's charge to mass ratio including radiation, de/dm, derived as the 4th order tensor measure. In this paper, I will discuss the latest update of the model and the ability of the equation of motion with radiation reaction in quantum vacuum via photon-photon scatterings.

  14. An analogue model for controllable Casimir radiation in a nonlinear cavity with amplitude-modulated pumping: Generation and quantum statistical properties

    E-Print Network [OSTI]

    Ali Motazedifard; M. H. Naderi; R. Roknizadeh

    2015-05-07T23:59:59.000Z

    We present and investigate an analogue model for a controllable photon geberation via the dynamical Casimir effect (DCE) in a cavity containing a degenerate optical amplifier (OPA) which is pumed by an amplitude-modulated field. The time modulation of the pump field in the model OPA system is equivalent to a periodic modulation of the cavity length, which is responsible for the generation of the Casimir radiation. By taking into account the rapidly oscillating terms of the modulation frequency, the effects of the corresponding counter-rotating terms (CRTs) on the analogue Casimir radiation emerge clearly. We find that the mean number of generated photons and their quantum statistical properties exhibit oscillatory behaviors, which are controllable through the modulation frequency as an external control parameter.We also recognize a new phenomenon, the so-called "Anti-DCE," in which pair photons can be coherently annihilated due to the time-modulated pumping. We show that the Casimir radiation exhibits quadrature squeezing, photon bunching and super-Poissonian statistics which are controllable by modulation frequency. We also calculate the power spectrum of the intracavity light field. We find that the appearance of the side bands in the spectrum is due to the presence of the CRTs.

  15. Satellite-based remote sensing of cirrus clouds: hyperspectral radiative transfer modeling, analysis of uncertainties in in-situ cloud extinction measurements and intercomparison of cirrus retrievals from a-train instruments 

    E-Print Network [OSTI]

    Zhang, Zhibo

    2009-05-15T23:59:59.000Z

    This dissertation consists of three parts, each devoted to a particular issue of significant importance for satellite-based remote sensing of cirrus clouds. In the first part, we develop and present a fast infrared radiative transfer model...

  16. Radiative Transitions in Charmonium

    SciTech Connect (OSTI)

    Jozef Dudek; Robert Edwards; David Richards

    2005-10-01T23:59:59.000Z

    The form factors for the radiative transitions between charmonium mesons are investigated. We employ an anisotropic lattice using a Wilson gauge action, and domain-wall fermion action. We extrapolate the form factors to Q{sup 2} = 0, corresponding to a real photon, using quark-model-inspired functions. Finally, comparison is made with photocouplings extracted from the measured radiative widths, where known. Our preliminary results find photocouplings commensurate with these experimentally extracted values.

  17. Comparison between Model Simulations and Measurements of Hyperspectral Far- infrared Radiation from FIRST during the RHUBC-II Campaign

    E-Print Network [OSTI]

    Baugher, Elizabeth

    2012-02-14T23:59:59.000Z

    to be inferred from the brightness temperature differences at 250 and 559.5 cm-1. Aerosols proved to reduce downwelling radiance by half that a clear-sky would emit, but had little effect on the total far-IR radiative forcing. Furthermore, these far...

  18. HYDRODYNAMIC AND RADIATIVE MODELING OF TEMPORAL H{alpha} EMISSION V/R VARIATIONS CAUSED BY DISCONTINUOUS MASS TRANSFER IN BINARIES

    SciTech Connect (OSTI)

    Chadima, Pavel; Harmanec, Petr; Wolf, Marek [Astronomical Institute of the Charles University, Faculty of Mathematics and Physics, V Holesovickach 2, CZ-180 00 Praha 8 (Czech Republic); Firt, Roman [Mathematical Institute, University of Bayreuth, D-95447 Bayreuth (Germany); Ruzdjak, Domagoj; Bozic, Hrvoje [Hvar Observatory, Faculty of Geodesy, University of Zagreb, 10000 Zagreb (Croatia); Koubsky, Pavel, E-mail: pavel.chadima@gmail.com [Astronomical Institute of the Academy of Sciences, CZ-251 65 Ondrejov (Czech Republic)

    2011-07-15T23:59:59.000Z

    H{alpha} emission V/R variations caused by discontinuous mass transfer in interacting binaries with a rapidly rotating accreting star are modeled qualitatively for the first time. The program ZEUS-MP was used to create a non-linear three-dimensional hydrodynamical model of a development of a blob of gaseous material injected into an orbit around a star. It resulted in the formation of an elongated disk with a slow prograde revolution. The LTE radiative transfer program SHELLSPEC was used to calculate the H{alpha} profiles originating in the disk for several phases of its revolution. The profiles have the form of a double emission and exhibit V/R and radial velocity variations. However, these variations should be a temporal phenomenon since imposing a viscosity in the given model would lead to a circularization of the disk and fading-out of the given variations.

  19. Impact of subgrid-scale radiative heating variability on the...

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

    subgrid-scale radiative heating variability on the stratocumulus-to-trade cumulus transition in climate models. Impact of subgrid-scale radiative heating variability on the...

  20. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.; Zaider, M.

    1993-05-01T23:59:59.000Z

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  1. Development and testing of parameterizations for continental and tropical ice cloud microphysical and radiative properties in GCM and mesoscale models. Final report

    SciTech Connect (OSTI)

    Heymsfield, A.

    1997-09-01T23:59:59.000Z

    The overall purpose of this research was to exploit measurements in clouds sampled during several field programs, especially from experiments in tropical regions, in a four-component study to develop and validate cloud parameterizations for general circulation models, emphasizing ice clouds. The components were: (1) parameterization of basic properties of mid- and upper-tropospheric clouds, such as condensed water content, primarily with respect to cirrus from tropical areas; (2) the second component was to develop parameterizations which express cloud radiative properties in terms of basic cloud microphysical properties, dealing primarily with tropical oceanic cirrus clouds and continental thunderstorm anvils, but also including altocumulus clouds; (3) the third component was to validate the parameterizations through use of ground-based measurements calibrated using existing and planned in-situ measurements of cloud microphysical properties and bulk radiative properties, as well as time-resolved data collected over extended periods of time; (4) the fourth component was to implement the parameterizations in the National Center for Atmospheric Research (NCAR) community climate model (CCM) II or in the NOAA-GFDL model (by L. Donner GFDL) and to perform sensitivity studies.

  2. Dosimetric accuracy of a deterministic radiation transport based {sup 192}Ir brachytherapy treatment planning system. Part III. Comparison to Monte Carlo simulation in voxelized anatomical computational models

    SciTech Connect (OSTI)

    Zourari, K.; Pantelis, E.; Moutsatsos, A.; Sakelliou, L.; Georgiou, E.; Karaiskos, P.; Papagiannis, P. [Medical Physics Laboratory, Medical School, University of Athens, 75 Mikras Asias, 115 27 Athens (Greece); Department of Physics, Nuclear and Particle Physics Section, University of Athens, Ilisia, 157 71 Athens (Greece); Medical Physics Laboratory, Medical School, University of Athens, 75 Mikras Asias, 115 27 Athens (Greece)

    2013-01-15T23:59:59.000Z

    Purpose: To compare TG43-based and Acuros deterministic radiation transport-based calculations of the BrachyVision treatment planning system (TPS) with corresponding Monte Carlo (MC) simulation results in heterogeneous patient geometries, in order to validate Acuros and quantify the accuracy improvement it marks relative to TG43. Methods: Dosimetric comparisons in the form of isodose lines, percentage dose difference maps, and dose volume histogram results were performed for two voxelized mathematical models resembling an esophageal and a breast brachytherapy patient, as well as an actual breast brachytherapy patient model. The mathematical models were converted to digital imaging and communications in medicine (DICOM) image series for input to the TPS. The MCNP5 v.1.40 general-purpose simulation code input files for each model were prepared using information derived from the corresponding DICOM RT exports from the TPS. Results: Comparisons of MC and TG43 results in all models showed significant differences, as reported previously in the literature and expected from the inability of the TG43 based algorithm to account for heterogeneities and model specific scatter conditions. A close agreement was observed between MC and Acuros results in all models except for a limited number of points that lay in the penumbra of perfectly shaped structures in the esophageal model, or at distances very close to the catheters in all models. Conclusions: Acuros marks a significant dosimetry improvement relative to TG43. The assessment of the clinical significance of this accuracy improvement requires further work. Mathematical patient equivalent models and models prepared from actual patient CT series are useful complementary tools in the methodology outlined in this series of works for the benchmarking of any advanced dose calculation algorithm beyond TG43.

  3. Radiation detector

    DOE Patents [OSTI]

    Fultz, Brent T. (Berkeley, CA)

    1983-01-01T23:59:59.000Z

    Apparatus is provided for detecting radiation such as gamma rays and X-rays generated in backscatter Mossbauer effect spectroscopy and X-ray spectrometry, which has a large "window" for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.

  4. Radiation detector

    DOE Patents [OSTI]

    Fultz, B.T.

    1980-12-05T23:59:59.000Z

    Apparatus is provided for detecting radiation such as gamma rays and x-rays generated in backscatter Moessbauer effect spectroscopy and x-ray spectrometry, which has a large window for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.

  5. Kingdom of Saudi Arabia Solar Radiation Atlas

    SciTech Connect (OSTI)

    NREL

    1998-12-16T23:59:59.000Z

    This atlas provides a record of monthly mean solar radiation generated by a Climatological Solar Radiation model, using quasi-climatological inputs of cloud cover, aerosol optical depth, precipitable water vapor, ozone, surface albedo, and atmospheric pressure.

  6. THE IMPORTANCE OF PHYSICAL MODELS FOR DERIVING DUST MASSES AND GRAIN SIZE DISTRIBUTIONS IN SUPERNOVA EJECTA. I. RADIATIVELY HEATED DUST IN THE CRAB NEBULA

    SciTech Connect (OSTI)

    Temim, Tea; Dwek, Eli, E-mail: tea.temim@nasa.gov [Observational Cosmology Lab, Code 665, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2013-09-01T23:59:59.000Z

    Recent far-infrared (IR) observations of supernova remnants (SNRs) have revealed significantly large amounts of newly condensed dust in their ejecta, comparable to the total mass of available refractory elements. The dust masses derived from these observations assume that all the grains of a given species radiate at the same temperature, regardless of the dust heating mechanism or grain radius. In this paper, we derive the dust mass in the ejecta of the Crab Nebula, using a physical model for the heating and radiation from the dust. We adopt a power-law distribution of grain sizes and two different dust compositions (silicates and amorphous carbon), and calculate the heating rate of each dust grain by the radiation from the pulsar wind nebula. We find that the grains attain a continuous range of temperatures, depending on their size and composition. The total mass derived from the best-fit models to the observed IR spectrum is 0.019-0.13 M{sub Sun }, depending on the assumed grain composition. We find that the power-law size distribution of dust grains is characterized by a power-law index of 3.5-4.0 and a maximum grain size larger than 0.1 {mu}m. The grain sizes and composition are consistent with what is expected for dust grains formed in a Type IIP supernova (SN). Our derived dust mass is at least a factor of two less than the mass reported in previous studies of the Crab Nebula that assumed more simplified two-temperature models. These models also require a larger mass of refractory elements to be locked up in dust than was likely available in the ejecta. The results of this study show that a physical model resulting in a realistic distribution of dust temperatures can constrain the dust properties and affect the derived dust masses. Our study may also have important implications for deriving grain properties and mass estimates in other SNRs and for the ultimate question of whether SNe are major sources of dust in the Galactic interstellar medium and in external galaxies.

  7. RADIATION SAFETY TRAINING MANUAL Radiation Safety Office

    E-Print Network [OSTI]

    Sibille, Etienne

    protection and the potential risks of ionizing radiation. Radiation Safety Office personnel provide.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 II. OVERVIEW OF REGULATIONS, PROTECTION STANDARDS, AND RADIATION SAFETY ORGANIZATION.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 V. BASIC RADIATION PROTECTION PRINCIPLES

  8. Radiation Safety

    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's PossibleRadiation Protection Radiation Protection Regulations: The Federal Regulation

  9. Modelling of long-range transport of Southeast Asia biomass-burning aerosols to Taiwan and their radiative forcings over East Asia

    SciTech Connect (OSTI)

    Lin, Chuan-Yao; Zhao, Chun; Liu, Xiaohong; Lin, Neng-Huei; Chen, Wei-Nei

    2014-10-12T23:59:59.000Z

    Biomass burning is a major source of aerosols and air pollutants during the springtime in Southeast Asia. At Lulin mountain background station (elevation 2862 m) in Taiwan, the concentrations of carbon monoxide (CO), ozone (O3) and particulate matter particles with diameter less than 10 ?m (PM10), were measured around 150-250 ppb, 40-60 ppb, and 10-30?g/m3, respectively at spring time (February-April) during 2006 and 2009, which are about 2~3 times higher than those in other seasons. Observations and simulation results indicate that the higher concentrations during the spring time are clearly related to biomass burning plumes transported from the Indochina Peninsula of Southeast Asia. The spatial distribution of high aerosols optical depth (AOD) were identified by the satellite measurement and Aerosol Robotic Network (AERONET) ground observation, and could be reasonably captured by the WRF-Chem model during the study period of 15-18 March, 2008. AOD reached as high as 0.8-1.0 in Indochina ranging from 10 to 22°N and 95 to 107°E. Organic carbon (OC) is a major contributor of AOD over Indochina according to simulation results. The contributor of AOD from black carbon (BC) is minor when compared with OC over the Indochina. However, the direct absorption radiative forcing of BC in the atmosphere could reach 35-50 W m-2, which is about 8-10 times higher than that of OC. The belt shape of radiation reduction at surface from Indochina to Taiwan could be as high 20-40 W m-2 during the study period. The implication of the radiative forcing from biomass burning aerosols and their impact on the regional climate in East Asia is our major concern.

  10. Modeling near-field radiative heat transfer from sharp objects using a general 3d numerical scattering technique

    E-Print Network [OSTI]

    McCauley, Alexander P; Krüger, Matthias; Johnson, Steven G

    2011-01-01T23:59:59.000Z

    We examine the non-equilibrium radiative heat transfer between a plate and finite cylinders and cones, making the first accurate theoretical predictions for the total heat transfer and the spatial heat flux profile for three-dimensional compact objects including corners or tips. We find qualitatively different scaling laws for conical shapes at small separations, and in contrast to a flat/slightly-curved object, a sharp cone exhibits a local \\emph{minimum} in the spatially resolved heat flux directly below the tip. The method we develop, in which a scattering-theory formulation of thermal transfer is combined with a boundary-element method for computing scattering matrices, can be applied to three-dimensional objects of arbitrary shape.

  11. The NCI Radiation Research Program: Grant portfolio and radiation

    E-Print Network [OSTI]

    models (89 animals no human subject material, 21 use both) ­ 109 utilize rodent models ­ 2 have canine and R37s). Of those that utilize radiation: · 6 use tissue culture models only · 110 utilize animal subjects · 39 use human subjects or human subject materials only. #12;Dose and Dosimetry · The majority

  12. Impact of Hillslope-Scale Organization of Topography, Soil Moisture, Soil Temperature, and Vegetation on Modeling Surface Microwave Radiation Emission

    E-Print Network [OSTI]

    Flores, Alejandro N.

    Microwave radiometry will emerge as an important tool for global remote sensing of near-surface soil moisture in the coming decade. In this modeling study, we find that hillslope-scale topography (tens of meters) influences ...

  13. Radiation receiver

    DOE Patents [OSTI]

    Hunt, A.J.

    1983-09-13T23:59:59.000Z

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

  14. Radiation receiver

    DOE Patents [OSTI]

    Hunt, Arlon J. (Oakland, CA)

    1983-01-01T23:59:59.000Z

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

  15. Gravitational Radiation

    E-Print Network [OSTI]

    Bernard F Schutz

    2000-03-16T23:59:59.000Z

    Gravity is one of the fundamental forces of Nature, and it is the dominant force in most astronomical systems. In common with all other phenomena, gravity must obey the principles of special relativity. In particular, gravitational forces must not be transmitted or communicated faster than light. This means that when the gravitational field of an object changes, the changes ripple outwards through space and take a finite time to reach other objects. These ripples are called gravitational radiation or gravitational waves. This article gives a brief introduction to the physics of gravitational radiation, including technical material suitable for non-specialist scientists.

  16. Gravitational radiation of a vibrating physical string as a model for the gravitational emission of an astrophysical plasma

    E-Print Network [OSTI]

    R. A. Lewis; G. Modanese

    2015-01-18T23:59:59.000Z

    The vibrating string is a source of gravitational waves which requires novel computational techniques, based on the explicit construction of a conserved and renormalized (in a classical sense) energy-momentum tensor. The renormalization is necessary to take into account the effect of external constraints, which affect the emission considerably. Vibrating media offer in general a testing ground for reconciling conflicts between General Relativity and other branches of physics; however, constraints are absent in sources like the Weber bar, for which the standard covariant formalism for elastic bodies can also be applied. Our solution method is based on the linearized Einstein equations, but relaxes other usual assumptions like far-field approximation, spherical or plane wave symmetry, TT gauge and source without internal interference. The string solution is then adapted to give the radiation field of a transversal Alfven wave in a rarefied plasma, where the tension is produced by an external static magnetic field. Like for the string, the field strength turns out to be independent from the frequency. We give a preliminary example of a numerical solution based on parameters referred to Alfven waves in the solar corona. Further astrophysical applications require an extension of the solution procedure to second order in the amplitude, and consideration of border effects. Future work will also address numerical and analytical near-field solutions.

  17. Radiation control coatings installed on federal buildings at Tyndall Air Force Base. Volume 2: Long-term monitoring and modeling

    SciTech Connect (OSTI)

    Petrie, T.W.; Childs, P.W.

    1998-06-01T23:59:59.000Z

    The US Department of Energy`s (DOE`s) Federal Energy Management Program (FEMP) supports efforts to reduce energy use and associated expenses in the federal sector. One such effort, the New Technology Demonstration Program (NTDP), seeks to evaluate new energy-saving US technologies and secure their more timely adoption by the US government. Through a partnership with a federal site, the utility serving the site, a manufacturer of an energy-related technology, and other organizations associated with these interests, DOE can evaluate a new technology. The results of the program give federal agency decision makers more hands-on information with which to validate a decision to utilize a new technology in their facilities. This is the second volume of a two-volume report that describes the effects of radiation control coatings installed on federal buildings at Tyndall Air Force Base (AFB) in Florida by ThermShield International. ORNL`s Buildings Technology Center (BTC) was assigned the responsibility for gathering, analyzing, and reporting on the data to describe the effects of the coatings. The first volume described the monitoring plan and its implementation, the results of pre-coating monitoring, the coating installation, results from fresh coatings compared to pre-coating results, and a plan to decommission the monitoring equipment. This second volume updates and completes the presentation of data to compare performance of fresh coatings with weathered coatings.

  18. A Challenge to Control Gravity via Applying Electromagnetic Low-Frequency Radiation - Theory and Proposed Model Experiments

    E-Print Network [OSTI]

    Julius Vanko; Miroslav Sukenik; Jozef Sima

    2007-05-29T23:59:59.000Z

    Including Vaidya metric into the model of Expansive Nondecelerative Universe allows to localize the energy of gravitational field. A term of effective gravitational range is introduced and classic Newton potential is substituted for Yukawa-type potential. It allows to allocate a typical frequency value to each gravitational field. Derived theoretical conclusions led us to investigate the effect of electromagnetic field with a precisely predetermined frequency and intensity on iron. We believe that under certain circumstances a decrease in iron gravitational mass should be observed. Two model experiments verifying the theoretical conclusions are proposed.

  19. Radiation Protection Act (Pennsylvania)

    Broader source: Energy.gov [DOE]

    This Act combines the radiation safety provisions of The Atomic Energy Development and Radiation Control Act and the Environmental Radiation Protection Act, and empowers the Department of...

  20. CSR by modal analysis Introduction

    E-Print Network [OSTI]

    Ellison, James

    singularities, and the resulting numerical problems can be controlled only with some difficulty. By contrast in bunch compressors with parallel conducting plates to represent the vacuum chamber. In this contribution. For a bunch compressor, the Z-axis would be the beam line direction. We denote with ¯E = ¯mc2 the energy

  1. CSR by modal analysis Introduction

    E-Print Network [OSTI]

    Ellison, James

    singularities, and the resulting numerical problems can be controlled only with some di#culty. By contrast in bunch compressors with parallel conducting plates to represent the vacuum chamber. In this contribution. For a bunch compressor, the Z­axis would be the beam line direction. We denote with � E = � #mc 2 the energy

  2. CSR Press Release Submitted by

    E-Print Network [OSTI]

    customers' needs in a sustainable way." For example in 2009, UPS drivers logged 77.3 million more miles than% by 2020, for a cumulative reduction of 42 percent since 1990. The airline represents 53% of the company by providing financial support, in-kind transportation and logistics expertise. The company launched UPS Road

  3. CSR Press Release Submitted by

    E-Print Network [OSTI]

    Samsung Electronics Co., Ltd Clean Technology, Corporate Social Responsibility Jul 28, 2010 ­ 10:00 PM EST-friendly products; lowered emissions Samsung Electronics Co., Ltd, a global leader in digital convergence technologies and device solutions, today announced the first year results of its sweeping Planet

  4. CSR Press Release Submitted by

    E-Print Network [OSTI]

    carbon dioxide-absorbing trees around the facility and in their neighborhoods and eliminated the wasteful volunteer projects that made a positive difference in the local communities worldwide," said Bruce Langos to manage emissions risks from operations and to identify cost-effective mitigation opportunities. According

  5. CIRCE: A dedicated storage ring for coherent THz synchrotron radiation

    E-Print Network [OSTI]

    2003-01-01T23:59:59.000Z

    coherent synchrotron radiation detected at BESSY II",BESSY[14]. Therefore the model is quite robust to different synchrotrons

  6. The aerosol direct radiative effect (DRE) over clouds is quantified using measured reflectance spectra of UV-absorbing aerosol polluted cloud scenes and modeled reflectance spectra of unpolluted cloud scenes. The cloud reflectance spectra are read from

    E-Print Network [OSTI]

    Graaf, Martin de

    distribution of clouds and aerosols along the white CALIPSO track in Fig.1b is shown in Fig. 2. The distanceThe aerosol direct radiative effect (DRE) over clouds is quantified using measured reflectance spectra of UV-absorbing aerosol polluted cloud scenes and modeled reflectance spectra of unpolluted cloud

  7. DEVELOPMENT OF A NOVEL RADIATIVELY/CONDUCTIVELY STABILIZED BURNER FOR SIGNIFICANT REDUCTION OF NOx EMISSIONS AND FOR ADVANCING THE MODELING AND UNDERSTANDING OF PULVERIZED COAL COMBUSTION AND EMISSIONS

    SciTech Connect (OSTI)

    Noam Lior; Stuart W. Churchill

    2003-10-01T23:59:59.000Z

    The primary objective of the proposed study was the study and analysis of, and design recommendations for, a novel radiatively-conductively stabilized combustion (RCSC) process for pulverized coal, which, based on our prior studies with both fluid fuels and pulverized coal, holds a high promise to reduce NO{sub x} production significantly. We have primarily engaged in continuing and improving our process modeling and analysis, obtained a large amount of quantitative information about the effects of the major parameters on NO{sub x} production, conducted an extensive exergy analysis of the process, evaluated the practicalities of employing the Radiatively-Conductively Stabilized Combustor (RCSC) to large power and heat plants, and improved the experimental facility. Prior experimental work has proven the feasibility of the combustor, but slagging during coal combustion was observed and should be dealt with. The primary outcomes and conclusions from the study are: (1) we developed a model and computer program that represents the pulverized coal combustion in the RCSC, (2) the model predicts that NO{sub x} emissions can be reduced by a number of methods, detailed in the report. (3) the exergy analysis points out at least a couple of possible ways to improve the exergetic efficiency in this combustor: increasing the effectiveness of thermal feedback, and adjusting the combustor mixture exit location, (4) because of the low coal flow rates necessitated in this study to obtain complete combustion in the burner, the size of a burner operating under the considered conditions would have to be up to an order of magnitude, larger than comparable commercial burners, but different flow configurations of the RCSC can yield higher feed rates and smaller dimensions, and should be investigated. Related to this contract, eleven papers were published in journals and conference proceedings, and ten invited presentations were given at university and research institutions, as well as at the Gordon Conference on Modern Development in Thermodynamics. The results obtained are very encouraging for the development of the RCSC as a commercial burner for significant reduction of NO{sub x} emissions, and highly warrants further study and development.

  8. Gravitational Radiation From Cosmological Turbulence

    E-Print Network [OSTI]

    Arthur Kosowsky; Andrew Mack; Tinatin Kahniashvili

    2002-06-27T23:59:59.000Z

    An injection of energy into the early Universe on a given characteristic length scale will result in turbulent motions of the primordial plasma. We calculate the stochastic background of gravitational radiation arising from a period of cosmological turbulence, using a simple model of isotropic Kolmogoroff turbulence produced in a cosmological phase transition. We also derive the gravitational radiation generated by magnetic fields arising from a dynamo operating during the period of turbulence. The resulting gravitational radiation background has a maximum amplitude comparable to the radiation background from the collision of bubbles in a first-order phase transition, but at a lower frequency, while the radiation from the induced magnetic fields is always subdominant to that from the turbulence itself. We briefly discuss the detectability of such a signal.

  9. FORECASTING SOLAR RADIATION PRELIMINARY EVALUATION OF AN APPROACH

    E-Print Network [OSTI]

    Perez, Richard R.

    FORECASTING SOLAR RADIATION -- PRELIMINARY EVALUATION OF AN APPROACH BASED UPON THE NATIONAL, and undertake a preliminary evaluation of, a simple solar radiation forecast model using sky cover predictions forecasts is 0.05o in latitude and longitude. Solar Radiation model: The model presented in this paper

  10. SU-E-T-50: Automatic Validation of Megavoltage Beams Modeled for Clinical Use in Radiation Therapy

    SciTech Connect (OSTI)

    Melchior, M [Terapia Radiante S.A., La Plata, Buenos Aires (Argentina); Salinas Aranda, F [Vidt Centro Medico, Ciudad Autonoma De Buenos Aires (Argentina); 21st Century Oncology, Ft. Myers, FL (United States); Sciutto, S [Universidad Nacional de La Plata, La Plata, Buenos Aires (Argentina); Dodat, D [Centro Medico Privado Dean Funes, La Plata, Buenos Aires (Argentina); Larragueta, N [Universidad Nacional de La Plata, La Plata, Buenos Aires (Argentina); Centro Medico Privado Dean Funes, La Plata, Buenos Aires (Argentina)

    2014-06-01T23:59:59.000Z

    Purpose: To automatically validate megavoltage beams modeled in XiO™ 4.50 (Elekta, Stockholm, Sweden) and Varian Eclipse™ Treatment Planning Systems (TPS) (Varian Associates, Palo Alto, CA, USA), reducing validation time before beam-on for clinical use. Methods: A software application that can automatically read and analyze DICOM RT Dose and W2CAD files was developed using MatLab integrated development environment.TPS calculated dose distributions, in DICOM RT Dose format, and dose values measured in different Varian Clinac beams, in W2CAD format, were compared. Experimental beam data used were those acquired for beam commissioning, collected on a water phantom with a 2D automatic beam scanning system.Two methods were chosen to evaluate dose distributions fitting: gamma analysis and point tests described in Appendix E of IAEA TECDOC-1583. Depth dose curves and beam profiles were evaluated for both open and wedged beams. Tolerance parameters chosen for gamma analysis are 3% and 3 mm dose and distance, respectively.Absolute dose was measured independently at points proposed in Appendix E of TECDOC-1583 to validate software results. Results: TPS calculated depth dose distributions agree with measured beam data under fixed precision values at all depths analyzed. Measured beam dose profiles match TPS calculated doses with high accuracy in both open and wedged beams. Depth and profile dose distributions fitting analysis show gamma values < 1. Relative errors at points proposed in Appendix E of TECDOC-1583 meet therein recommended tolerances.Independent absolute dose measurements at points proposed in Appendix E of TECDOC-1583 confirm software results. Conclusion: Automatic validation of megavoltage beams modeled for their use in the clinic was accomplished. The software tool developed proved efficient, giving users a convenient and reliable environment to decide whether to accept or not a beam model for clinical use. Validation time before beam-on for clinical use was reduced to a few hours.

  11. A Sensitivity Study of Radiative Fluxes at the Top of Atmosphere to Cloud-Microphysics and Aerosol Parameters in the Community Atmosphere Model CAM5

    SciTech Connect (OSTI)

    Zhao, Chun; Liu, Xiaohong; Qian, Yun; Yoon, Jin-Ho; Hou, Zhangshuan; Lin, Guang; McFarlane, Sally A.; Wang, Hailong; Yang, Ben; Ma, Po-Lun; Yan, Huiping; Bao, Jie

    2013-11-08T23:59:59.000Z

    In this study, we investigated the sensitivity of net radiative fluxes (FNET) at the top of atmosphere (TOA) to 16 selected uncertain parameters mainly related to the cloud microphysics and aerosol schemes in the Community Atmosphere Model version 5 (CAM5). We adopted a quasi-Monte Carlo (QMC) sampling approach to effectively explore the high dimensional parameter space. The output response variables (e.g., FNET) were simulated using CAM5 for each parameter set, and then evaluated using generalized linear model analysis. In response to the perturbations of these 16 parameters, the CAM5-simulated global annual mean FNET ranges from -9.8 to 3.5 W m-2 compared to the CAM5-simulated FNET of 1.9 W m-2 with the default parameter values. Variance-based sensitivity analysis was conducted to show the relative contributions of individual parameter perturbation to the global FNET variance. The results indicate that the changes in the global mean FNET are dominated by those of cloud forcing (CF) within the parameter ranges being investigated. The size threshold parameter related to auto-conversion of cloud ice to snow is confirmed as one of the most influential parameters for FNET in the CAM5 simulation. The strong heterogeneous geographic distribution of FNET variation shows parameters have a clear localized effect over regions where they are acting. However, some parameters also have non-local impacts on FNET variance. Although external factors, such as perturbations of anthropogenic and natural emissions, largely affect FNET variations at the regional scale, their impact is weaker than that of model internal parameters in terms of simulating global mean FNET in this study. The interactions among the 16 selected parameters contribute a relatively small portion of the total FNET variations over most regions of the globe. This study helps us better understand the CAM5 model behavior associated with parameter uncertainties, which will aid the next step of reducing model uncertainty via calibration of uncertain model parameters with the largest sensitivity.

  12. Outward migration of Jupiter and Saturn in 3:2 or 2:1 resonance in radiative disks: implications for the Grand Tack and Nice models

    E-Print Network [OSTI]

    Pierens, Arnaud; Nesvorny, David; Morbidelli, Alessandro

    2014-01-01T23:59:59.000Z

    Embedded in the gaseous protoplanetary disk, Jupiter and Saturn naturally become trapped in 3:2 resonance and migrate outward. This serves as the basis of the Grand Tack model. However, previous hydrodynamical simulations were restricted to isothermal disks, with moderate aspect ratio and viscosity. Here we simulate the orbital evolution of the gas giants in disks with viscous heating and radiative cooling. We find that Jupiter and Saturn migrate outward in 3:2 resonance in modest-mass ($M_{disk} \\approx M_{MMSN}$, where MMSN is the "minimum-mass solar nebula") disks with viscous stress parameter $\\alpha$ between $10^{-3}$ and $10^{-2} $. In disks with relatively low-mass ($M_{disk} \\lesssim M_{MMSN}$) , Jupiter and Saturn get captured in 2:1 resonance and can even migrate outward in low-viscosity disks ($\\alpha \\le 10^{-4}$). Such disks have a very small aspect ratio ($h\\sim 0.02-0.03$) that favors outward migration after capture in 2:1 resonance, as confirmed by isothermal runs which resulted in a similar o...

  13. Use of ARM observations and numerical models to determine radiative and latent heating profiles of mesoscale convective systems for general circulation models

    SciTech Connect (OSTI)

    Houze, Jr., Robert A. [University of Washington Dept. of Atmospheric Sciences

    2013-11-13T23:59:59.000Z

    We examined cloud radar data in monsoon climates, using cloud radars at Darwin in the Australian monsoon, on a ship in the Bay of Bengal in the South Asian monsoon, and at Niamey in the West African monsoon. We followed on with a more in-depth study of the continental MCSs over West Africa. We investigated whether the West African anvil clouds connected with squall line MCSs passing over the Niamey ARM site could be simulated in a numerical model by comparing the observed anvil clouds to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model at high resolution using six different ice-phase microphysical schemes. We carried out further simulations with a cloud-resolving model forced by sounding network budgets over the Niamey region and over the northern Australian region. We have devoted some of the effort of this project to examining how well satellite data can determine the global breadth of the anvil cloud measurements obtained at the ARM ground sites. We next considered whether satellite data could be objectively analyzed to so that their large global measurement sets can be systematically related to the ARM measurements. Further differences were detailed between the land and ocean MCS anvil clouds by examining the interior structure of the anvils with the satellite-detected the CloudSat Cloud Profiling Radar (CPR). The satellite survey of anvil clouds in the Indo-Pacific region was continued to determine the role of MCSs in producing the cloud pattern associated with the MJO.

  14. General Relativistic Radiative Transfer

    E-Print Network [OSTI]

    S. Knop; P. H. Hauschildt; E. Baron

    2006-11-30T23:59:59.000Z

    We present a general method to calculate radiative transfer including scattering in the continuum as well as in lines in spherically symmetric systems that are influenced by the effects of general relativity (GR). We utilize a comoving wavelength ansatz that allows to resolve spectral lines throughout the atmosphere. The used numerical solution is an operator splitting (OS) technique that uses a characteristic formal solution. The bending of photon paths and the wavelength shifts due to the effects of GR are fully taken into account, as is the treatment of image generation in a curved spacetime. We describe the algorithm we use and demonstrate the effects of GR on the radiative transport of a two level atom line in a neutron star like atmosphere for various combinations of continuous and line scattering coefficients. In addition, we present grey continuum models and discuss the effects of different scattering albedos on the emergent spectra and the determination of effective temperatures and radii of neutron star atmospheres.

  15. Radiation in molecular dynamic simulations

    SciTech Connect (OSTI)

    Glosli, J; Graziani, F; More, R; Murillo, M; Streitz, F; Surh, M

    2008-10-13T23:59:59.000Z

    Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of Megabars to thousands of Gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The new technique passes a key test: it relaxes to a blackbody spectrum for a plasma in local thermodynamic equilibrium. This new tool also provides a method for assessing the accuracy of energy and momentum exchange models in hot dense plasmas. As an example, we simulate the evolution of non-equilibrium electron, ion, and radiation temperatures for a hydrogen plasma using the new molecular dynamics simulation capability.

  16. Fermion masses and neutrino mixing in an U(1){sub H} flavor symmetry model with hierarchical radiative generation for light charged fermion masses

    SciTech Connect (OSTI)

    Hernandez-Galeana, Albino [Departamento de Fisica de la Escuela Superior de Fisica y Matematicas, Instituto Politecnico Nacional, U.P. Adolfo Lopez Mateos, C.P. 07738. Mexico D.F. (Mexico)

    2007-11-01T23:59:59.000Z

    I report the analysis performed on fermion masses and mixing, including neutrino mixing, within the context of a model with hierarchical radiative mass generation mechanism for light charged fermions, mediated by exotic scalar particles at one and two loops, respectively, meanwhile the neutrinos get Majorana mass terms at tree level through the Yukawa couplings with two SU(2){sub L} Higgs triplets. All the resulting mass matrices in the model, for the u, d, and e fermion charged sectors, the neutrinos and the exotic scalar particles, are diagonalized in exact analytical form. Quantitative analysis shows that this model is successful to accommodate the hierarchical spectrum of masses and mixing in the quark sector as well as the charged lepton masses. The lepton mixing matrix, V{sub PMNS}, is written completely in terms of the neutrino masses m{sub 1}, m{sub 2}, and m{sub 3}. Large lepton mixing for {theta}{sub 12} and {theta}{sub 23} is predicted in the range of values 0.7 < or approx. sin{sup 2}2{theta}{sub 12} < or approx. 0.7772 and 0.87 < or approx. sin{sup 2}2{theta}{sub 23} < or approx. 0.9023 by using 0.033 < or approx. s{sub 13}{sup 2} < or approx. 0.04. These values for lepton mixing are consistent with 3{sigma} allowed ranges provided by recent global analysis of neutrino data oscillation. From {delta}m{sub sol}{sup 2} bounds, neutrino masses are predicted in the range of values m{sub 1}{approx_equal}(1.706-2.494)x10{sup -3} eV, m{sub 2}{approx_equal}(6.675-12.56)x10{sup -3} eV, and m{sub 3}{approx_equal}(1.215-2.188)x10{sup -2} eV, respectively. The above allowed lepton mixing leads to the quark-lepton complementary relations {theta}{sub 12}{sup CKM}+{theta}{sub 12}{sup PMNS}{approx_equal}41.543 deg. -44.066 deg. and {theta}{sub 23}{sup CKM}+{theta}{sub 23}{sup PMNS}{approx_equal}36.835 deg. -38.295 deg. The new exotic scalar particles induce flavor changing neutral currents and contribute to lepton flavor violating processes such as E{yields}e{sub 1}e{sub 2}e{sub 3}, to radiative rare decays, {tau}{yields}{mu}{gamma}, {tau}{yields}e{gamma}, {mu}{yields}e{gamma}, as well as to the anomalous magnetic moments of fermions. I give general analytical expressions for the branching ratios of these rare decays and for the anomalous magnetic moments for charged leptons.

  17. Split SUSY Radiates Flavor

    E-Print Network [OSTI]

    Matthew Baumgart; Daniel Stolarski; Thomas Zorawski

    2014-09-19T23:59:59.000Z

    Radiative flavor models where the hierarchies of Standard Model (SM) fermion masses and mixings are explained via loop corrections are elegant ways to solve the SM flavor puzzle. Here we build such a model in the context of Mini-Split Supersymmetry (SUSY) where both flavor and SUSY breaking occur at a scale of 1000 TeV. This model is consistent with the observed Higgs mass, unification, and WIMP dark matter. The high scale allows large flavor mixing among the sfermions, which provides part of the mechanism for radiative flavor generation. In the deep UV, all flavors are treated democratically, but at the SUSY breaking scale, the third, second, and first generation Yukawa couplings are generated at tree level, one loop, and two loops, respectively. Save for one, all the dimensionless parameters in the theory are O(1), with the exception being a modest and technically natural tuning that explains both the smallness of the bottom Yukawa coupling and the largeness of the Cabibbo angle.

  18. Adaptors for radiation detectors

    DOE Patents [OSTI]

    Livesay, Ronald Jason

    2014-04-22T23:59:59.000Z

    Described herein are adaptors and other devices for radiation detectors that can be used to make accurate spectral measurements of both small and large bulk sources of radioactivity, such as building structures, soils, vessels, large equipment, and liquid bodies. Some exemplary devices comprise an adaptor for a radiation detector, wherein the adaptor can be configured to collimate radiation passing through the adapter from an external radiation source to the radiation detector and the adaptor can be configured to enclose a radiation source within the adapter to allow the radiation detector to measure radiation emitted from the enclosed radiation source.

  19. Radiation dosimeters

    DOE Patents [OSTI]

    Hoelsher, James W. (Pullman, WA); Hegland, Joel E. (Pullman, WA); Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA)

    1992-01-01T23:59:59.000Z

    Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.

  20. Meeting Report--NASA Radiation Biomarker Workshop

    SciTech Connect (OSTI)

    Straume, Tore; Amundson, Sally A,; Blakely, William F.; Burns, Frederic J.; Chen, Allen; Dainiak, Nicholas; Franklin, Stephen; Leary, Julie A.; Loftus, David J.; Morgan, William F.; Pellmar, Terry C.; Stolc, Viktor; Turteltaub, Kenneth W.; Vaughan, Andrew T.; Vijayakumar, Srinivasan; Wyrobek, Andrew J.

    2008-05-01T23:59:59.000Z

    A summary is provided of presentations and discussions from the NASA Radiation Biomarker Workshop held September 27-28, 2007, at NASA Ames Research Center in Mountain View, California. Invited speakers were distinguished scientists representing key sectors of the radiation research community. Speakers addressed recent developments in the biomarker and biotechnology fields that may provide new opportunities for health-related assessment of radiation-exposed individuals, including for long-duration space travel. Topics discussed include the space radiation environment, biomarkers of radiation sensitivity and individual susceptibility, molecular signatures of low-dose responses, multivariate analysis of gene expression, biomarkers in biodefense, biomarkers in radiation oncology, biomarkers and triage following large-scale radiological incidents, integrated and multiple biomarker approaches, advances in whole-genome tiling arrays, advances in mass-spectrometry proteomics, radiation biodosimetry for estimation of cancer risk in a rat skin model, and confounding factors. Summary conclusions are provided at the end of the report.

  1. 11th International Conference of Radiation Research

    SciTech Connect (OSTI)

    NONE

    1999-07-18T23:59:59.000Z

    Topics discussed in the conference included the following: Radiation Physics, Radiation Chemistry and modelling--Radiation physics and dosimetry; Electron transfer in biological media; Radiation chemistry; Biophysical and biochemical modelling; Mechanisms of DNA damage; Assays of DNA damage; Energy deposition in micro volumes; Photo-effects; Special techniques and technologies; Oxidative damage. Molecular and cellular effects-- Photobiology; Cell cycle effects; DNA damage: Strand breaks; DNA damage: Bases; DNA damage Non-targeted; DNA damage: other; Chromosome aberrations: clonal; Chromosomal aberrations: non-clonal; Interactions: Heat/Radiation/Drugs; Biochemical effects; Protein expression; Gene induction; Co-operative effects; ``Bystander'' effects; Oxidative stress effects; Recovery from radiation damage. DNA damage and repair -- DNA repair genes; DNA repair deficient diseases; DNA repair enzymology; Epigenetic effects on repair; and Ataxia and ATM.

  2. Geant4 applications in the heliospheric radiation environment

    E-Print Network [OSTI]

    Pedro Brogueira; Patrícia Gonçalves; Ana Keating; Dalmiro Maia; Mário Pimenta; Bernardo Tomé

    2007-09-11T23:59:59.000Z

    The high energy ionizing radiation environment in the solar system consists of three main sources: the radiation belts, galactic cosmic rays and solar energetic particles. Geant4 is a Monte Carlo radiation transport simulation toolkit, with applications in areas as high energy physics, nuclear physics, astrophysics or medical physics research. In this poster, Geant4 applications to model and study the effects of the heliospheric radiation environment are presented. Specific applications are being developed to study the effect of the radiation environment on detector components, to describe the response and to optimise the design of radiation monitors for future space missions and to predict the radiation environment in Mars surface, orbits and moons.

  3. Quasi light fields: Extending the light field to coherent radiation

    E-Print Network [OSTI]

    Accardi, Anthony J.

    Imaging technologies such as dynamic viewpoint generation are engineered for incoherent radiation using the traditional light field, and for coherent radiation using electromagnetic field theory. We present a model of ...

  4. environmental management radiation protection

    E-Print Network [OSTI]

    Entekhabi, Dara

    EHS environmental management biosafety radiation protection industrial hygiene safety Working: Biosafety, Environmental Management, Industrial Hygiene, Radiation Protection and Safety. Each specialized Management Program, Industrial Hygiene, Radiation Protection Program, and the Safety Program. (http

  5. DETECTORS FOR RADIATION DOSIMETRY

    E-Print Network [OSTI]

    Perez-Mendez, V.

    2010-01-01T23:59:59.000Z

    J. Price, "Nuclear Radiation Detection" (2nd ed. , New York:4) G. F. Knoll, "Radiation Detection and Measurement" (NewSons, Inc. from "Radiation Detection and Measurement," G. F.

  6. Optical Properties of Saharan Dust and Asian Dust: Application to Radiative Transfer Simulations 

    E-Print Network [OSTI]

    Fang, Guangyang

    2012-07-16T23:59:59.000Z

    properties for radiative transfer simulations. Using a Rapid Radiative Transfer Model (RRTM), the radiative forcing of mineral dust was computed at both the top of the atmosphere and the surface. By analyzing samples from various in-situ measurements, we...

  7. Courses on Synchrotron Radiation

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

    Synchrotron Radiation The following is an incomplete list of courses on Synchrotron Radiation. For additional courses, check lightsources.org. XAFS School The APS XAFS School...

  8. Solar radiation resource assessment

    SciTech Connect (OSTI)

    Not Available

    1990-11-01T23:59:59.000Z

    The bulletin discusses the following: introduction; Why is solar radiation resource assessment important Understanding the basics; the solar radiation resource assessment project; and future activities.

  9. Radiation Control (Virginia)

    Broader source: Energy.gov [DOE]

    The Department of Health is responsible for regulating radiation and radioactive materials in the Commonwealth of Virginia. Although the Department's Radiation Control Program primarily focuses on...

  10. QCD Radiation off Heavy Particles

    E-Print Network [OSTI]

    Torbjörn Sjöstrand

    2000-12-15T23:59:59.000Z

    An algorithm for an improved description of final-state QCD radiation is introduced. It is matched to the first-order matrix elements for gluon emission in a host of decays, for processes within the Standard Model and the Minimal Supersymmetric extension thereof.

  11. Radiation Shielding for Fusion Reactors

    SciTech Connect (OSTI)

    Santoro, R.T.

    1999-10-01T23:59:59.000Z

    Radiation shielding requirements for fusion reactors present different problems than those for fission reactors and accelerators. Fusion devices, particularly tokamak reactors, are complicated by geometry constraints that complicate disposition of fully effective shielding. This paper reviews some of these shielding issues and suggested solutions for optimizing the machine and biological shielding. Radiation transport calculations are essential for predicting and confirming the nuclear performance of the reactor and, as such, must be an essential part of the reactor design process. Development and optimization of reactor components from the first wall and primary shielding to the penetrations and containment shielding must be carried out in a sensible progression. Initial results from one-dimensional transport calculations are used for scoping studies and are followed by detailed two- and three-dimensional analyses to effectively characterize the overall radiation environment. These detail model calculations are essential for accounting for the radiation leakage through ports and other penetrations in the bulk shield. Careful analysis of component activation and radiation damage is cardinal for defining remote handling requirements, in-situ replacement of components, and personnel access at specific locations inside the reactor containment vessel. Radiation shielding requirements for fusion reactors present different problems than those for fission reactors and accelerators. Fusion devices, particularly tokamak reactors, are complicated by geometry constraints that complicate disposition of fully effective shielding. This paper reviews some of these shielding issues and suggested solutions for optimizing the machine and biological shielding. Radiation transport calculations are essential for predicting and confirming the nuclear performance of the reactor and, as such, must be an essential part of the reactor design process. Development and optimization of reactor components from the first wall and primary shielding to the penetrations and containment shielding must be carried out in a sensible progression. Initial results from one-dimensional transport calculations are used for scoping studies and are followed by detailed two- and three-dimensional analyses to effectively characterize the overall radiation environment. These detail model calculations are essential for accounting for the radiation leakage through ports and other penetrations in the bulk shield. Careful analysis of component activation and radiation damage is cardinal for defining remote handling requirements, in-situ replacement of components, and personnel access at specific locations inside the reactor containment vessel.

  12. Discussion on spin-flip synchrotron radiation

    E-Print Network [OSTI]

    V. A. Bordovitsyn; V. S. Gushchina; A. N. Myagkii

    2001-02-12T23:59:59.000Z

    Quantum spin-flip transitions are of great importance in the synchrotron radiation theory. For better understanding of the nature of this phenomenon, it is necessary to except the effects connected with the electric charge radiation from observation. This fact explains the suggested choice of the spin-flip radiation model in the form of radiation of the electric neutral Dirac-Pauli particle moving in the homogeneous magnetic field. It is known that in this case, the total radiation in the quantum theory is conditioned by spin-flip transitions. The idea is that spin-flip radiation is represented as a nonstationary process connected with spin precession. We shall shown how to construct a solution of the classical equation of the spin precession in the BMT theory having the exact solution of the Dirac-Pauli equation.Thus, one will find the connection of the quantum spin-flip transitions with classical spin precession.

  13. Radiation in Lorentz violating electrodynamics

    E-Print Network [OSTI]

    R. Montemayor; L. F. Urrutia

    2004-12-02T23:59:59.000Z

    Synchrotron radiation is analyzed in the classical effective Lorentz invariance violating model of Myers-Pospelov. Within the full far-field approximation we compute the electric and magnetic fields, the angular distribution of the power spectrum and the total emitted power in the m-th harmonic, as well as the polarization. We find the appearance of rather unexpected and large amplifying factors, which go together with the otherwise negligible naive expansion parameter. This opens up the possibility of further exploring Lorentz invariance violations by synchrotron radiation measurements in astrophysical sources where these amplifying factors are important.

  14. Atmospheric response to solar radiation absorbed by phytoplankton

    E-Print Network [OSTI]

    Shell, Karen M.

    Atmospheric response to solar radiation absorbed by phytoplankton K. M. Shell and R. Frouin Scripps the absorption of solar radiation, affecting upper ocean temperature and circulation. These changes, in turn: phytoplankton, atmospheric general circulation model (AGCM), absorption of solar radiation, seasonal cycle, sea

  15. RADIATIVE HEAT TRANSFER WITH QUASIMONTE CARLO METHODS \\Lambda

    E-Print Network [OSTI]

    RADIATIVE HEAT TRANSFER WITH QUASI­MONTE CARLO METHODS \\Lambda A. Kersch 1 W. Morokoff 2 A accuracy modeling of the radiative heat transfer from the heater to the wafer. Figure 1 shows the draft Carlo simulation is often used to solve radiative transfer problems where complex physical phenomena

  16. RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS

    E-Print Network [OSTI]

    RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS A. Kersch1 W. Moroko2 A. Schuster1 1Siemens of Quasi-Monte Carlo to this problem. 1.1 Radiative Heat Transfer Reactors In the manufacturing of the problems which can be solved by such a simulation is high accuracy modeling of the radiative heat transfer

  17. Parameterization of contrail radiative properties for climate studies

    E-Print Network [OSTI]

    Liou, K. N.

    the current and potential effect on global climate change. The line-shaped artificial clouds often visible radiation and absorb infrared radiation emitted from the Earth and atmosphere, and the effect on the global climate change requires a cloud model that statistically represents contrail radiative properties

  18. Plutonium radiation surrogate

    DOE Patents [OSTI]

    Frank, Michael I. (Dublin, CA)

    2010-02-02T23:59:59.000Z

    A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

  19. A Dedicated Storage Ring For Far-IR Coherent Synchrotron Radiation at the ALS

    E-Print Network [OSTI]

    infrared community is being constructed. The first observation of steady CSR at BESSY II [4] has recently by the product between the number of particles per bunch N and the single particle emitted power p

  20. Radiation Protection Guidance Hospital Staff

    E-Print Network [OSTI]

    Kay, Mark A.

    Page 1 Radiation Protection Guidance For Hospital Staff Prepared for Stanford ..................................................................................................................... 17 The Basic Principles of Radiation Protection........................................................... 17 Protection against Radiation Exposure

  1. Radiation Detection Computational Benchmark Scenarios

    SciTech Connect (OSTI)

    Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.

    2013-09-24T23:59:59.000Z

    Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNL’s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for compilation. This is a report describing the details of the selected Benchmarks and results from various transport codes.

  2. ModelingLandBiogeochemistry Term Spring 2014

    E-Print Network [OSTI]

    Ma, Lena

    of Earth system models and serve to represent exchange of energy (heat radiation momentum), water, carbon

  3. Maryland Radiation Act (Maryland)

    Broader source: Energy.gov [DOE]

    The policy of the state is to provide for the constructive use of radiation and control radiation emissions. This legislation authorizes the Department of the Environment to develop comprehensive...

  4. WI Radiation Protection

    Broader source: Energy.gov [DOE]

    This statute seeks to regulate radioactive materials, to encourage the constructive uses of radiation, and to prohibit and prevent exposure to radiation in amounts which are or may be detrimental...

  5. Radiation protection at CERN

    E-Print Network [OSTI]

    Forkel-Wirth, Doris; Silari, Marco; Streit-Bianchi, Marilena; Theis, Christian; Vincke, Heinz; Vincke, Helmut

    2013-01-01T23:59:59.000Z

    This paper gives a brief overview of the general principles of radiation protection legislation; explains radiological quantities and units, including some basic facts about radioactivity and the biological effects of radiation; and gives an overview of the classification of radiological areas at CERN, radiation fields at high-energy accelerators, and the radiation monitoring system used at CERN. A short section addresses the ALARA approach used at CERN.

  6. Calculating Radiative Heat Transfer in an Axisymmetric Closed Chamber: An Application

    E-Print Network [OSTI]

    New York at Stoney Brook, State University of

    the parallelization of the radiative heat transfer model introduced by Naraghi and Nunes of Manhattan College [8

  7. RADIONUCLIDE RADIATION PROTECTION

    E-Print Network [OSTI]

    Healy, Kevin Edward

    RADIONUCLIDE AND RADIATION PROTECTION DATA HANDBOOK 2002 D. Delacroix* J. P. Guerre** P. Leblanc'Energie Atomique, CEA/Saclay, France ISBN 1 870965 87 6 RADIATION PROTECTION DOSIMETRY Vol. 98 No 1, 2002 Published by Nuclear Technology Publishing #12;RADIONUCLIDE AND RADIATION PROTECTION DATA HANDBOOK 2nd Edition (2002

  8. Radiation Processing -an overview

    E-Print Network [OSTI]

    of radiation · Facilities ­ Gamma ­ electrons ­ X-ray ­ Safety · Sterilisation of medical devices · Food irradiation · Material modification #12;3 Content ­ Part 2 · Environmental applications · Other applications Radiation · Energy in the form of waves or moving subatomic particles Irradiation · Exposure to radiation

  9. Classical Radiation Reaction in Particle-In-Cell Simulations

    E-Print Network [OSTI]

    Vranic, Marija; Fonseca, Ricardo A; Silva, Luis O

    2015-01-01T23:59:59.000Z

    Under the presence of ultra high intensity lasers or other intense electromagnetic fields the motion of particles in the ultrarelativistic regime can be severely affected by radiation reaction. The standard particle-in-cell (PIC) algorithms do not include radiation reaction effects. Even though this is a well known mechanism, there is not yet a definite algorithm nor a standard technique to include radiation reaction in PIC codes. We have compared several models for the calculation of the radiation reaction force, with the goal of implementing an algorithm for classical radiation reaction in the Osiris framework, a state-of-the-art PIC code. The results of the different models are compared with standard analytical results, and the relevance/advantages of each model are discussed. Numerical issues relevant to PIC codes such as resolution requirements, application of radiation reaction to macro particles and computational cost are also addressed. The Landau and Lifshitz reduced model is chosen for implementatio...

  10. Synchrotron Radiation in Polymer Science

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

    Synchrotron Radiation in Polymer Science Synchrotron Radiation in Polymer Science March 30-April 2, 2012; San Francisco...

  11. TERSat: Trapped Energetic Radiation Satellite

    E-Print Network [OSTI]

    Clements, Emily B.

    2012-01-01T23:59:59.000Z

    Radiation damage caused by interactions with high-energy particles in the Van Allen Radiation Belts is a leading

  12. First Coherent Synchrotron Radiation Scientific Results: Measuring the Josephson Plasma Resonance in Bi2Sr2CaCu2O8

    E-Print Network [OSTI]

    -Strasse 2, D-12489 Berlin, Germany In a collaboration between the ALS and BESSY to make a first of operation at the BESSY synchrotron which produces stable CSR. Figure 1 shows a comparison of the measured. Measured far-IR intensity of the BESSY CSR source compared to the intensity for conventional thermal far

  13. Radiative heat transfer in porous uranium dioxide

    SciTech Connect (OSTI)

    Hayes, S.L. [Texas A and M Univ., College Station, TX (United States)] [Texas A and M Univ., College Station, TX (United States)

    1992-12-01T23:59:59.000Z

    Due to low thermal conductivity and high emissivity of UO{sub 2}, it has been suggested that radiative heat transfer may play a significant role in heat transfer through pores of UO{sub 2} fuel. This possibility was computationally investigated and contribution of radiative heat transfer within pores to overall heat transport in porous UO{sub 2} quantified. A repeating unit cell was developed to model approximately a porous UO{sub 2} fuel system, and the heat transfer through unit cells representing a wide variety of fuel conditions was calculated using a finite element computer program. Conduction through solid fuel matrix as wekk as pore gas, and radiative exchange at pore surface was incorporated. A variety of pore compositions were investigated: porosity, pore size, shape and orientation, temperature, and temperature gradient. Calculations were made in which pore surface radiation was both modeled and neglected. The difference between yielding the integral contribution of radiative heat transfer mechanism to overall heat transport. Results indicate that radiative component of heat transfer within pores is small for conditions representative of light water reactor fuel, typically less than 1% of total heat transport. It is much larger, however, for conditions present in liquid metal fast breeder reactor fuel; during restructuring of this fuel type early in life, the radiative heat transfer mode was shown to contribute as much as 10-20% of total heat transport in hottest regions of fuel.

  14. Planck's Radiation Law in the Quantized Universe

    E-Print Network [OSTI]

    Rainer Collier

    2014-09-15T23:59:59.000Z

    Physical research looks for clues to quantum properties of the gravitational field. On the basis of the common Schr\\"odinger theory, a simple model of the quantization of a Friedmann universe comprising dust and radiation is investigated. With regard to energy quantization, the result suggests a universal limitation of the energy spacing between neighbouring quantum states by the Planck energy. Applied to black-body radiation, a modified Planck radiation law follows. If this could be verified in the laboratory, it would provide a direct hint at quantum properties of the space-time manifold.

  15. ON THE SOLAR RADIATION BUDGET AND THE CLOUD ABSORPTION ANOMALY DEBATE

    E-Print Network [OSTI]

    Li, Zhanqing

    ON THE SOLAR RADIATION BUDGET AND THE CLOUD ABSORPTION ANOMALY DEBATE ZHANQING LI Department-of-the-art radiative transfer models. 1. Introduction Solar radiation is the ultimate source of energy for the planet of solar radiation, which is unfortunately still fraught with large uncertainties (Wild et al. 1995; Li et

  16. Tissue Radiation Response with Maximum Tsallis Entropy

    SciTech Connect (OSTI)

    Sotolongo-Grau, O.; Rodriguez-Perez, D.; Antoranz, J. C.; Sotolongo-Costa, Oscar [UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain); UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain) and University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba); University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba)

    2010-10-08T23:59:59.000Z

    The expression of survival factors for radiation damaged cells is currently based on probabilistic assumptions and experimentally fitted for each tumor, radiation, and conditions. Here, we show how the simplest of these radiobiological models can be derived from the maximum entropy principle of the classical Boltzmann-Gibbs expression. We extend this derivation using the Tsallis entropy and a cutoff hypothesis, motivated by clinical observations. The obtained expression shows a remarkable agreement with the experimental data found in the literature.

  17. The ionizing radiation environment in space and its effects

    SciTech Connect (OSTI)

    Adams, Jim; Falconer, David; Fry, Dan [Center for Space Plasma and Aeronomic Research (CSPAR), UA Huntsville (United States); Space Radiation Analysis Group, NASA Johnson Space Center (United States)

    2012-11-20T23:59:59.000Z

    The ionizing radiation environment in space poses a hazard for spacecraft and space crews. The hazardous components of this environment are reviewed and those which contribute to radiation hazards and effects identified. Avoiding the adverse effects of space radiation requires design, planning, monitoring and management. Radiation effects on spacecraft are avoided largely though spacecraft design. Managing radiation exposures of space crews involves not only protective spacecraft design and careful mission planning. Exposures must be managed in real time. The now-casting and forecasting needed to effectively manage crew exposures is presented. The techniques used and the space environment modeling needed to implement these techniques are discussed.

  18. Surface Radiation from GOES: A Physical Approach; Preprint

    SciTech Connect (OSTI)

    Habte, A.; Sengupta, M.; Wilcox, S.

    2012-09-01T23:59:59.000Z

    Models to compute Global Horizontal Irradiance (GHI) and Direct Normal Irradiance (DNI) have been in development over the last 3 decades. These models can be classified as empirical or physical, based on the approach. Empirical models relate ground based observations with satellite measurements and use these relations to compute surface radiation. Physical models consider the radiation received from the earth at the satellite and create retrievals to estimate surface radiation. While empirical methods have been traditionally used for computing surface radiation for the solar energy industry the advent of faster computing has made operational physical models viable. The Global Solar Insolation Project (GSIP) is an operational physical model from NOAA that computes GHI using the visible and infrared channel measurements from the GOES satellites. GSIP uses a two-stage scheme that first retrieves cloud properties and uses those properties in a radiative transfer model to calculate surface radiation. NREL, University of Wisconsin and NOAA have recently collaborated to adapt GSIP to create a 4 km GHI and DNI product every 30 minutes. This paper presents an outline of the methodology and a comprehensive validation using high quality ground based solar data from the National Oceanic and Atmospheric Administration (NOAA) Surface Radiation (SURFRAD) (http://www.srrb.noaa.gov/surfrad/sitepage.html) and Integrated Surface Insolation Study (ISIS) http://www.srrb.noaa.gov/isis/isissites.html), the Solar Radiation Research Laboratory (SRRL) at National Renewable Energy Laboratory (NREL), and Sun Spot One (SS1) stations.

  19. Solar radiation intensity calculations

    E-Print Network [OSTI]

    Levine, Randolph Steven

    1978-01-01T23:59:59.000Z

    SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Submitted to the Graduate College of Texas A&M University in partia'l fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject...: Physics SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Approved as to style and content by: (Chairman of Committee) (Member) (Member) ( member) (Head of Department) December 1978 f219 037 ABSTRACT Solar Radiation...

  20. Atomic Radiation (Illinois)

    Broader source: Energy.gov [DOE]

    This article states permissible levels of radiation in unrestricted areas, environmental standards for uranium fuel cycle and information about notification of incidents.

  1. Radiation Hazards Program (Minnesota)

    Broader source: Energy.gov [DOE]

    These regulations, promulgated by the Department of Health, set allowable radiation standards and mitigation practices, as well as procedures for the transportation of hazardous material.

  2. Rotating bubble membrane radiator

    DOE Patents [OSTI]

    Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

    1988-12-06T23:59:59.000Z

    A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

  3. Has Hawking radiation been measured?

    E-Print Network [OSTI]

    W. G. Unruh

    2014-01-26T23:59:59.000Z

    It is argued that Hawking radiation has indeed been measured and shown to posses a thermal spectrum, as predicted. This contention is based on three separate legs. The first is that the essential physics of the Hawking process for black holes can be modelled in other physical systems. The second is the white hole horizons are the time inverse of black hole horizons, and thus the physics of both is the same. The third is that the quantum emission, which is the Hawking process, is completely determined by measurements of the classical parameters of a linear physical system. The experiment conducted in 2010 fulfills all of these requirements, and is thus a true measurement of Hawking radiation.

  4. The Impact of Abrupt Suspension of Solar Radiation Management (Termination Effect) in Experiment G2 of the Geoengineering Model Intercomparison Project (GeoMIP)

    SciTech Connect (OSTI)

    Jones, Andrew; Haywood, J.; Alterskjaer, Kari; Boucher, Olivier; Cole, Jason N.; Curry, Charles L.; Irvine, Peter; Ji, Duoying; Kravitz, Benjamin S.; Kristjansson, Jon E.; Moore, John; Niemeier, Ulrike; Robock, Alan; Schmidt, Hauke; Singh, Balwinder; Tilmes, S.; Watanabe, Shingo; Yoon, Jin-Ho

    2013-09-11T23:59:59.000Z

    We have examined changes in climate which result from the sudden termination of geoengineering after 50 years of offsetting a 1% per annum increase in CO2 concentra- tions as simulated by 11 different climate models in experiment G2 of the Geoengineering Model Intercomparison Project. The models agree on a rapid rate of global-mean warming following termination, accompanied by increases in global-mean precipitation rate and in plant net primary productivity, and decreases in sea-ice cover. While there is a considerable degree of consensus for the geographical distribution of warming, there is much less of an agreement regarding the patterns of change in the other quantities.

  5. Radiation physics, biophysics, and radiation biology

    SciTech Connect (OSTI)

    Hall, E.J.

    1992-05-01T23:59:59.000Z

    The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent.

  6. Radiation Reaction in High-Intense Fields

    E-Print Network [OSTI]

    Seto, Keita

    2015-01-01T23:59:59.000Z

    After the development of the radiating electron model by P. A. M. Dirac in 1938, many authors have tried to reformulate this model so-called radiation reaction. Recently, this effects has become important for ultra-intense laser-electron (plasma) interactions. In our recent research, we found a method for the stabilization of radiation reaction in quantum vacuum [PTEP 2014, 043A01 (2014), PTEP 2015, 023A01 (2015)]. In the other hand, the field modification by high-intense fields should be required under 10PW lasers, like ELI-NP facility. In this paper, I propose the combined method how to adopt the high-intense field correction with the stabilization by quantum vacuum as the extension from the model by Dirac.

  7. Satellite-based estimates of net radiation and modeling the role of topography and vegetation on inter-annual hydro-climatology

    E-Print Network [OSTI]

    Bisht, Gautam

    2010-01-01T23:59:59.000Z

    The Fourth Assessment Report of the Intergovernmental Panel on Climate Change acknowledged that the lack of relevant observations in various regions of the world is a crucial gap in understanding and modeling impacts of ...

  8. The Extreme Gamma-Ray Blazar S5 0716+714: Jet Conditions from Radio-Band Variability and Radiative Transfer Modeling

    E-Print Network [OSTI]

    Aller, M F; Aller, H D; Jorstad, S G; Marscher, A P; Bala, V; Hovatta, T

    2015-01-01T23:59:59.000Z

    As part of a program to identify the physical conditions in the jets of gamma-ray-flaring blazars detected by Fermi, including the role of shocks in the production of high-energy flaring, we obtained 4 years of 3-frequency, centimeter-band total flux density and linear polarization monitoring observations of the radio-bright blazar S5 0716+714 with the University of Michigan 26-m paraboloid. Light curves constructed from these data exhibit a series of rapid, high-amplitude, centimeter-band total flux density outbursts, and changes in the linear polarization consistent with the passage of shocks during the gamma-ray flaring. The observed spectral evolution of the radio-band flares, in combination with radiative transfer simulations incorporating propagating shocks, was used to constrain the shock and jet flow conditions in the parsec-scale regions of the jet. Eight forward-moving, transverse shocks with unusually-strong shock compression factors, a very fast Lorentz factor of the shocks of 77, a bulk Lorentz f...

  9. COLUMBIA UNIVERSITY Radiation Safety Program

    E-Print Network [OSTI]

    Jia, Songtao

    for increased protection from ionizing radiation for declared pregnant radiation workers. The radiation doseCOLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212-305-0303 F: 212 regulations of the Rules of the City of New York, Article 175, Radiation Control, there is a requirement

  10. Solar Radiation Prediction and Energy Allocation for Energy Harvesting Base Stations

    E-Print Network [OSTI]

    Solar Radiation Prediction and Energy Allocation for Energy Harvesting Base Stations Yanan Bao@tsinghua.edu.cn Abstract--In this paper, we study how to use the solar radiation model to predict energy arrivals solar radiation is reviewed and summarized. We present two solar energy models for cloudless days

  11. Radiation-resistant microorganism

    DOE Patents [OSTI]

    Fliermans, Carl B.

    2010-06-15T23:59:59.000Z

    An isolated and purified bacterium is provided which was isolated from a high-level radioactive waste site of mixed waste. The isolate has the ability to degrade a wide variety of organic contaminants while demonstrating high tolerance to ionizing radiation. The organism is uniquely suited to bioremediation of a variety or organic contaminants while in the presence of ionizing radiation.

  12. Nonclassicality of Thermal Radiation

    E-Print Network [OSTI]

    Lars M. Johansen

    2004-02-16T23:59:59.000Z

    It is demonstrated that thermal radiation of small occupation number is strongly nonclassical. This includes most forms of naturally occurring radiation. Nonclassicality can be observed as a negative weak value of a positive observable. It is related to negative values of the Margenau-Hill quasi-probability distribution.

  13. Radiative Flux Analysis

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Long, Chuck [NOAA

    The Radiative Flux Analysis is a technique for using surface broadband radiation measurements for detecting periods of clear (i.e. cloudless) skies, and using the detected clear-sky data to fit functions which are then used to produce continuous clear-sky estimates. The clear-sky estimates and measurements are then used in various ways to infer cloud macrophysical properties.

  14. Radiation-resistant microorganism

    DOE Patents [OSTI]

    Fliermans, Carl B.

    2007-01-09T23:59:59.000Z

    An isolated and purified bacterium is provided which was isolated from a high-level radioactive waste site of mixed waste. The isolate has the ability to degrade a wide variety of organic contaminants while demonstrating high tolerance to ionizing radiation. The organism is uniquely suited to bioremediation of a variety or organic contaminants while in the presence of ionizing radiation.

  15. Radiation detection system

    DOE Patents [OSTI]

    Franks, Larry A. (Santa Barbara, CA); Lutz, Stephen S. (Santa Barbara, CA); Lyons, Peter B. (Los Alamos, NM)

    1981-01-01T23:59:59.000Z

    A radiation detection system including a radiation-to-light converter and fiber optic wave guides to transmit the light to a remote location for processing. The system utilizes fluors particularly developed for use with optical fibers emitting at wavelengths greater than about 500 nm and having decay times less than about 10 ns.

  16. Nuclear radiation actuated valve

    DOE Patents [OSTI]

    Christiansen, David W. (Kennewick, WA); Schively, Dixon P. (Richland, WA)

    1985-01-01T23:59:59.000Z

    A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  17. RADIATION SAFETY MANUAL POLICIES AND PROCEDURES

    E-Print Network [OSTI]

    Zhang, Yuanlin

    RADIATION SAFETY MANUAL POLICIES AND PROCEDURES FOR RADIATION PROTECTION AT TEXAS TECH UNIVERSITY................................................................................................................I-1 B. Radiation Protection Program...............................................................................I-3 D. Radiation Safety Management

  18. Radiative and climate impacts of absorbing aerosols

    E-Print Network [OSTI]

    Zhu, Aihua

    2010-01-01T23:59:59.000Z

    V. Ramanathan (2008), Solar radiation budget and radiativeV. Ramanathan (2008), Solar radiation budget and radiativeapproximation for solar radiation in the NCAR Community

  19. COLUMBIA UNIVERSITY Radiation Safety Program

    E-Print Network [OSTI]

    Jia, Songtao

    COLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212-305-0303 F: 212 Psychiatric Institute Radiation Safety Office (Please complete this form within 24 hours and send a copy to your supervisor and The Radiation Safety Office) Your Name

  20. COLUMBIA UNIVERSITY Radiation Safety Program

    E-Print Network [OSTI]

    Jia, Songtao

    COLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212-305-0303 F: 212: _______________ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Radiation Safety Office Approval: ______________________ Date: ________________________ Waste containers in place: Yes ___ No ___ Radiation signage on door: Yes ___ No ___ Room monitoring: Dates

  1. Radiation Safety (Revised March 2010)

    E-Print Network [OSTI]

    Kay, Mark A.

    to Workers; Inspections 27 10 CFR Part 20Standards for Protection Against Radiation 28 10 CFR Part 35Radiation Safety Manual (Revised March 2010) Updated December 2012 Stanford University, Stanford California #12; #12; Radiation Safety Manual (Revised March 2010) Updated

  2. Common Origin of 3.55 keV X-Ray Line and Galactic Center Gamma Ray Excess in a Radiative Neutrino Mass Model

    E-Print Network [OSTI]

    Borah, Debasish; Adhikari, Rathin

    2015-01-01T23:59:59.000Z

    We attempt to simultaneously explain the recently observed 3.55 keV X-ray line in the analysis of XMM-Newton telescope data and the galactic center gamma ray excess observed by the Fermi gamma ray space telescope within an abelian gauge extension of standard model. We consider a two component dark matter scenario with a mass difference 3.55 keV such that the heavier one can decay into the lighter one and a photon with energy 3.55 keV. The lighter dark matter candidate is protected from decaying into the standard model particles by a remnant $Z_2$ symmetry into which the abelian gauge symmetry gets spontaneously broken. If the mass of the dark matter particle is chosen to be within $31-40$ GeV, then this model can also explain the galactic center gamma ray excess if the dark matter annihilation into $b\\bar{b}$ pairs has a cross section of $\\langle \\sigma v \\rangle \\simeq (1.4-2.0) \\times 10^{-26} \\; \\text{cm}^3/\\text{s}$. We constrain the model from the requirement of producing correct dark matter relic densit...

  3. Evaluation of electric and magnetic fields distribution and SAR induced in 3D models of water containers by radiofrequency radiation using FDTD and FEM simulation techniques

    E-Print Network [OSTI]

    Abdelsamie, Maher A A; Mustafa, Shuhaimi; Hashim, Dzulkifly

    2014-01-01T23:59:59.000Z

    In this study, two software packages using different numerical techniques FEKO 6.3 with Finite-Element Method (FEM) and XFDTD 7 with Finite Difference Time Domain Method (FDTD) were used to assess exposure of 3D models of square, rectangular, and pyramidal shaped water containers to electromagnetic waves at 300, 900, and 2400 MHz frequencies. Using the FEM simulation technique, the peak electric field of 25, 4.5, and 2 V/m at 300 MHz and 15.75, 1.5, and 1.75 V/m at 900 MHz were observed in pyramidal, rectangular, and square shaped 3D container models, respectively. The FDTD simulation method confirmed a peak electric field of 12.782, 10.907, and 10.625 V/m at 2400 MHz in the pyramidal, square, and rectangular shaped 3D models, respectively. The study demonstrated an exceptionally high level of electric field in the water in the two identical pyramid shaped 3D models analyzed using the two different simulation techniques. Both FEM and FDTD simulation techniques indicated variations in the distribution of elect...

  4. The Local Interstellar Ultraviolet Radiation Field

    E-Print Network [OSTI]

    Richard Conn Henry

    2002-01-03T23:59:59.000Z

    I have used the Hipparcos Input Catalog, together with Kurucz model stellar atmospheres, and information on the strength of the interstellar extinction, to create a model of the expected intensity and spectral distribution of the local interstellar ultraviolet radiation field, under various assumptions concerning the albedo a of the interstellar grains. (This ultraviolet radiation field is of particular interest because of the fact that ultraviolet radiation is capable of profoundly affecting the chemistry of the interstellar medium.) By comparing my models with the observations, I am able to conclude that the albedo a of the interstellar grains in the far ultraviolet is very low, perhaps a = 0.1. I also advance arguments that my present determination of this albedo is much more reliable than any of the many previous (and conflicting) ultraviolet interstellar grain albedo determinations. Beyond this, I show that the ultraviolet background radiation that is observed at high galactic latitudes must be extragalactic in origin, as it cannot be backscatter of the interstellar radiation field.

  5. Dissecting Soft Radiation with Factorization

    E-Print Network [OSTI]

    Iain W. Stewart; Frank J. Tackmann; Wouter J. Waalewijn

    2015-02-10T23:59:59.000Z

    An essential part of high-energy hadronic collisions is the soft hadronic activity that underlies the primary hard interaction. It includes soft radiation from the primary hard partons, secondary multiple parton interactions (MPI), and factorization-violating effects. The invariant mass spectrum of the leading jet in $Z$+jet and $H$+jet events is directly sensitive to these effects, and we use a QCD factorization theorem to predict its dependence on the jet radius $R$, jet $p_T$, jet rapidity, and partonic process for both the perturbative and nonperturbative components of primary soft radiation. We prove that the nonperturbative contributions involve only odd powers of $R$, and the linear $R$ term is universal for quark and gluon jets. The hadronization model in PYTHIA8 agrees well with these properties. The perturbative soft initial state radiation (ISR) has a contribution that depends on the jet area in the same way as the underlying event, but this degeneracy is broken by dependence on the jet $p_T$. The size of this soft ISR contribution is proportional to the color state of the initial partons, yielding the same positive contribution for $gg\\to Hg$ and $gq\\to Zq$, but a negative interference contribution for $q\\bar q\\to Z g$. Hence, measuring these dependencies allows one to separate hadronization, soft ISR, and MPI contributions in the data.

  6. Classical Helium Atom with Radiation Reaction

    E-Print Network [OSTI]

    G. Camelio; A. Carati; L. Galgani

    2011-11-24T23:59:59.000Z

    We study a classical model of Helium atom in which, in addition to the Coulomb forces, the radiation reaction forces are taken into account. This modification brings in the model a new qualitative feature of a global character. Indeed, as pointed out by Dirac, in any model of classical electrodynamics of point particles involving radiation reaction one has to eliminate, from the a priori conceivable solutions of the problem, those corresponding to the emission of an infinite amount of energy. We show that the Dirac prescription solves a problem of inconsistency plaguing all available models which neglect radiation reaction, namely, the fact that in all such models most initial data lead to a spontaneous breakdown of the atom. A further modification is that the system thus acquires a peculiar form of dissipation. In particular, this makes attractive an invariant manifold of special physical interest, the zero--dipole manifold, that corresponds to motions in which no energy is radiated away (in the dipole approximation). We finally study numerically the invariant measure naturally induced by the time--evolution on such a manifold, and this corresponds to studying the formation process of the atom. Indications are given that such a measure may be singular with respect to that of Lebesgue.

  7. Florida Radiation Protection Act (Florida)

    Broader source: Energy.gov [DOE]

    The Department of Public Health is responsible for administering a statewide radiation protection program. The program is designed to permit development and utilization of sources of radiation for...

  8. SYNCHROTRON RADIATION SOURCES

    SciTech Connect (OSTI)

    HULBERT,S.L.; WILLIAMS,G.P.

    1998-07-01T23:59:59.000Z

    Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

  9. CSR AND THE RURAL ELECTRIFICATION CHALLENGE 

    E-Print Network [OSTI]

    Joss, Kristina

    2011-11-24T23:59:59.000Z

    renewable energy for rural electrification in the least developed countries. Using first hand interviews with industry experts to support academic literature and policy report analysis, this dissertation argues that corporations are a necessary tool...

  10. IEEE Consumer Electronics Society Standards Architect, CSR

    E-Print Network [OSTI]

    California at Davis, University of

    applications Managing charging at home: Smart Energy Profile Keeping the car: avoiding collisions with DSRC #12;IEEE Consumer Electronics Society 3 Other subjects addressed Keynote: Policy and Technology PEV Market been studying the impact of a "Smart Grid" They produced a report titled 1108 rev 2: Framework

  11. The Intense Radiation Gas

    E-Print Network [OSTI]

    M. Marklund; P. K. Shukla; B. Eliasson

    2005-03-08T23:59:59.000Z

    We present a new dispersion relation for photons that are nonlinearly interacting with a radiation gas of arbitrary intensity due to photon-photon scattering. It is found that the photon phase velocity decreases with increasing radiation intensity, it and attains a minimum value in the limit of super-intense fields. By using Hamilton's ray equations, a self-consistent kinetic theory for interacting photons is formulated. The interaction between an electromagnetic pulse and the radiation gas is shown to produce pulse self-compression and nonlinear saturation. Implications of our new results are discussed.

  12. Composition for radiation shielding

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1994-01-01T23:59:59.000Z

    A composition for use as a radiation shield. The shield has a depleted urum core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container.

  13. Miniaturized radiation chirper

    DOE Patents [OSTI]

    Umbarger, C. John (Los Alamos, NM); Wolf, Michael A. (Los Alamos, NM)

    1980-01-01T23:59:59.000Z

    The disclosure relates to a miniaturized radiation chirper for use with a small battery supplying on the order of 5 volts. A poor quality CdTe crystal which is not necessarily suitable for high resolution gamma ray spectroscopy is incorporated with appropriate electronics so that the chirper emits an audible noise at a rate that is proportional to radiation exposure level. The chirper is intended to serve as a personnel radiation warning device that utilizes new and novel electronics with a novel detector, a CdTe crystal. The resultant device is much smaller and has much longer battery life than existing chirpers.

  14. Galaxy formation with radiative and chemical feedback

    E-Print Network [OSTI]

    Graziani, L; Schneider, R; Kawata, D; de Bennassuti, M; Maselli, A

    2015-01-01T23:59:59.000Z

    Here we introduce GAMESH, a novel pipeline which implements self-consistent radiative and chemical feedback in a computational model of galaxy formation. By combining the cosmological chemical-evolution model GAMETE with the radiative transfer code CRASH, GAMESH can post process realistic outputs of a N-body simulation describing the redshift evolution of the forming galaxy. After introducing the GAMESH implementation and its features, we apply the code to a low-resolution N-body simulation of the Milky Way formation and we investigate the combined effects of self-consistent radiative and chemical feedback. Many physical properties, which can be directly compared with observations in the Galaxy and its surrounding satellites, are predicted by the code along the merger-tree assembly. The resulting redshift evolution of the Local Group star formation rates, reionisation and metal enrichment along with the predicted Metallicity Distribution Function of halo stars are critically compared with observations. We dis...

  15. Portal radiation monitor

    DOE Patents [OSTI]

    Kruse, Lyle W. (Albuquerque, NM)

    1985-01-01T23:59:59.000Z

    A portal radiation monitor combines 0.1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

  16. The Gravitational Cherenkov Radiation

    E-Print Network [OSTI]

    A. M. Ignatov

    2001-10-26T23:59:59.000Z

    An example of discontinuity of the energy-momentum tensor moving at superluminal velocity is discussed. It is shown that the gravitational Mach cone is formed. The power spectrum of the corresponding Cherenkov radiation is evaluated.

  17. Radiation from Accelerated Branes

    E-Print Network [OSTI]

    Mohab Abou-Zeid; Miguel S. Costa

    2000-01-29T23:59:59.000Z

    The radiation emitted by accelerated fundamental strings and D-branes is studied within the linear approximation to the supergravity limit of string theory. We show that scalar, gauge field and gravitational radiation is generically emitted by such branes. In the case where an external scalar field accelerates the branes, we derive a Larmor-type formula for the emitted scalar radiation and study the angular distribution of the outgoing energy flux. The classical radii of the branes are calculated by means of the corresponding Thompson scattering cross sections. Within the linear approximation, the interaction of the external scalar field with the velocity fields of the branes gives a contribution to the observed gauge field and gravitational radiation.

  18. Adaptive multigroup radiation diffusion

    E-Print Network [OSTI]

    Williams, Richard B., Sc. D. Massachusetts Institute of Technology

    2005-01-01T23:59:59.000Z

    This thesis describes the development and implementation of an algorithm for dramatically increasing the accuracy and reliability of multigroup radiation diffusion simulations at low group counts. This is achieved by ...

  19. Ionizing radiation detector

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1990-01-01T23:59:59.000Z

    An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

  20. Amorphous silicon radiation detectors

    DOE Patents [OSTI]

    Street, Robert A. (Palo Alto, CA); Perez-Mendez, Victor (Berkeley, CA); Kaplan, Selig N. (El Cerrito, CA)

    1992-01-01T23:59:59.000Z

    Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification.

  1. Amorphous silicon radiation detectors

    DOE Patents [OSTI]

    Street, R.A.; Perez-Mendez, V.; Kaplan, S.N.

    1992-11-17T23:59:59.000Z

    Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification. 13 figs.

  2. Radiation Safety Training Basic Radiation Safety Training for

    E-Print Network [OSTI]

    Dai, Pengcheng

    Radiation Safety Training Basic Radiation Safety Training for X-ray Users for Physics 461 & 462 Protocol Title: Basic Radiation Safety Training for X-ray Users Drafted By: Chris Millsaps, RSS Reviewers: ZB, TU, GS Purpose: To provide basic radiation safety training to the users of x-ray producing

  3. Radiation Safety Manual Dec 2012 Page 1 RADIATION SAFETY

    E-Print Network [OSTI]

    Grishok, Alla

    of External and Internal Doses E. Reports and Notices to Workers Chapter VII: Radiation ProtectionRadiation Safety Manual ­ Dec 2012 Page 1 RADIATION SAFETY MANUAL For Columbia University NewYork-Presbyterian Hospital New York State Psychiatric Institute Barnard College December 2012 #12;Radiation Safety Manual

  4. Method of enhancing radiation response of radiation detection materials

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1997-01-01T23:59:59.000Z

    The present invention is a method of increasing radiation response of a radiation detection material for a given radiation signal by first pressurizing the radiation detection material. Pressurization may be accomplished by any means including mechanical and/or hydraulic. In this application, the term "pressure" includes fluid pressure and/or mechanical stress.

  5. Quasi light fields: extending the light field to coherent radiation

    E-Print Network [OSTI]

    Wornell, Gregory W.

    Quasi light fields: extending the light field to coherent radiation Anthony Accardi1,2 and Gregory light field, and for coherent radiation using electromagnetic field theory. We present a model of coherent image formation that strikes a balance between the utility of the light field

  6. CognitiveEngineeringinRadiationScreeningfor HomelandSecurity

    E-Print Network [OSTI]

    Parasuraman, Raja

    areas through work domain analysis, signal detection modeling, design of displays for radiation threatCognitiveEngineeringinRadiationScreeningfor HomelandSecurity Thomas F. Sanquist Brian Minsk Pacific for illicit radioactive material involves substantial staff, technology, and human operator decision making

  7. Density matrix of black hole radiation

    E-Print Network [OSTI]

    Lasma Alberte; Ram Brustein; Andrei Khmelnitsky; A. J. M. Medved

    2015-02-09T23:59:59.000Z

    Hawking's model of black hole evaporation is not unitary and leads to a mixed density matrix for the emitted radiation, while the Page model describes a unitary evaporation process in which the density matrix evolves from an almost thermal state to a pure state. We compare a recently proposed model of semiclassical black hole evaporation to the two established models. In particular, we study the density matrix of the outgoing radiation and determine how the magnitude of the off-diagonal corrections differs for the three frameworks. For Hawking's model, we find power-law corrections to the two-point functions that induce exponentially suppressed corrections to the off-diagonal elements of the full density matrix. This verifies that the Hawking result is correct to all orders in perturbation theory and also allows one to express the full density matrix in terms of the single-particle density matrix. We then consider the semiclassical theory for which the corrections, being non-perturbative from an effective field-theory perspective, are much less suppressed and grow monotonically in time. In this case, the R\\'enyi entropy for the outgoing radiation is shown to grow linearly at early times; but this growth slows down and the entropy eventually starts to decrease at the Page time. In addition to comparing models, we emphasize the distinction between the state of the radiation emitted from a black hole, which is highly quantum, and that of the radiation emitted from a typical classical black body at the same temperature.

  8. Radiative Processes Working Group

    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's PossibleRadiation Protection Radiation Protection Regulations: The

  9. Quantum Chaos and the Black Body Radiation

    E-Print Network [OSTI]

    Giulio Casati

    2000-11-16T23:59:59.000Z

    We discuss a mechanical model which mimics the main features of the radiation matter interaction in the black body problem. The pure classical dynamical evolution, with a simple discretization of the action variables, leads to the Stefan- Boltzmann law and to the Planck distribution without any additional statistical assumption.

  10. Bell-inequality violation with "thermal" radiation

    E-Print Network [OSTI]

    Radim Filip; Miloslav Dusek; Jaromir Fiurasek; Ladislav Mista

    2001-05-17T23:59:59.000Z

    The model of a quantum-optical device for a conditional preparation of entangled states from input mixed states is presented. It is demonstrated that even thermal or pseudo-thermal radiation can be entangled in such a way, that Bell-inequalities are violated.

  11. Charmonium meson and hybrid radiative transitions

    SciTech Connect (OSTI)

    Guo, Peng [Indiana U., JLAB; Yépez-Martínez, Tochtli [Indiana U.; Szczepaniak, Adam P. [Indiana U., JLAB

    2014-06-01T23:59:59.000Z

    We consider the non-relativistic limit of the QCD Hamiltonian in the Coulomb gauge, to describe radiative transitions between conventional charmonium states and from the lowest multiplet of cc¯ hybrids to charmonium mesons. The results are compared to potential quark models and lattices calculations.

  12. RADIATION PERMIT APPLICATION Western Human Resources

    E-Print Network [OSTI]

    Sinnamon, Gordon J.

    and Model of Radiation Device (if applicable) Experimental Protocol Describe in detail your experimental the aspects that pertain to safety issues, describe any special hazards, and include the following: 1. Brief will be performed 7. Provide a waste disposal flow chart indicating approx. activities (mCi or MBq) for each type

  13. Radiation analysis devices, radiation analysis methods, and articles of manufacture

    DOE Patents [OSTI]

    Roybal, Lyle Gene

    2010-06-08T23:59:59.000Z

    Radiation analysis devices include circuitry configured to determine respective radiation count data for a plurality of sections of an area of interest and combine the radiation count data of individual of sections to determine whether a selected radioactive material is present in the area of interest. An amount of the radiation count data for an individual section is insufficient to determine whether the selected radioactive material is present in the individual section. An article of manufacture includes media comprising programming configured to cause processing circuitry to perform processing comprising determining one or more correction factors based on a calibration of a radiation analysis device, measuring radiation received by the radiation analysis device using the one or more correction factors, and presenting information relating to an amount of radiation measured by the radiation analysis device having one of a plurality of specified radiation energy levels of a range of interest.

  14. Gravitational Tunneling Radiation

    E-Print Network [OSTI]

    Mario Rabinowitz

    2002-12-11T23:59:59.000Z

    The isolated black hole radiation of both Hawking and Zel'dovich are idealized abstractions as there is always another body to distort the potential. This is considered with respect to both gravitational tunneling, and black hole "no-hair" theorems. The effects of a second body are to lower the gravitational barrier of a black hole and to give the barrier a finite rather than infinite width so tha a particle can escape by tunneling (as in field emission) or over the top of the lowered barrier (as in Schottky emission). Thus radiation may be emitted from black holes in a process differing from that of Hawking radiation, P SH, which has been undetected for over 24 years. The radiated power from a black hole derived here is PR e ^2__ PSH, where e ^2__ is he ransmission probability for radiation through the barrier. This is similar to electric field emission of electrons from a metal in that the emission can in principle be modulated and beamed. The temperature and entropy of black holes are reexamined. Miniscule black holes herein may help explain the missing mass of the universe, accelerated expansion of the universe, and anomalous rotation of spiral galaxies. A gravitational interference effect for black hole radiation similar to the Aharonov-Bohm effect is also examined.

  15. Packet personal radiation monitor

    DOE Patents [OSTI]

    Phelps, James E. (Knoxville, TN)

    1989-01-01T23:59:59.000Z

    A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiation events, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible "chirp". The rate of the "chirps" is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field.

  16. Scattering of particles by radiation fields: a comparative analysis

    E-Print Network [OSTI]

    Donato Bini; Andrea Geralico; Maria Haney; Robert T. Jantzen

    2014-08-22T23:59:59.000Z

    The features of the scattering of massive neutral particles propagating in the field of a gravitational plane wave are compared with those characterizing their interaction with an electromagnetic radiation field. The motion is geodesic in the former case, whereas in the case of an electromagnetic pulse it is accelerated by the radiation field filling the associated spacetime region. The interaction with the radiation field is modeled by a force term entering the equations of motion proportional to the 4-momentum density of radiation observed in the particle's rest frame. The corresponding classical scattering cross sections are evaluated too.

  17. GENII. Environmental Radiation Dosimetry Suite

    SciTech Connect (OSTI)

    Napier, B.A. [Pacific Northwest Lab., Richland, WA, (United States)

    1988-12-01T23:59:59.000Z

    GENII was developed to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) into the environmental pathway analysis models used at Hanford. GENII is a coupled system of seven programs and the associated data libraries that comprise the Hanford Dosimetry System (Generation II) to estimate potential radiation doses to individuals or populations from both routine and accidental releases of radionuclides to air or water and residual contamination from spills or decontamination operations. The GENII system includes interactive menu-driven programs to assist the user with scenario generation and data input,internal and external dose factor generators, and environmental dosimetry programs. The programs analyze environmental contamination resulting from both far-field and near-field scenarios. A far-field scenario focuses outward from a source, while a near-field scenario focuses in toward a receptor. GENII can calculate annual dose, committed dose, and accumulated dose from acute and chronic releases from ground or elevated sources to air or water and from initial contamination of soil or surfaces and can evaluate exposure pathways including direct exposure via water, soil, air, inhalation pathways, and ingestion pathways. In addition, GENII can perform 10,000 years migration analyses and can be used for retrospective calculations of potential radiation doses resulting from routine emissions and for prospective dose calculations for purposes such as siting facilities, environmental impact statements, and safety analysis reports.

  18. Working With Radiation For Research

    E-Print Network [OSTI]

    Jia, Songtao

    working with radiation The radiation badge is not a protective device It cannot shield you from ­ Negative Exponential Protection From Radiation #12;18 Time Distance Shielding Basic Principles #121 Working With Radiation For Research Thomas Cummings Junior Physicist Environmental Health

  19. Radiation Safety Annual Refresher Training

    E-Print Network [OSTI]

    Thomas, David D.

    Radiation Safety Annual Refresher Training Radiation Protection Division Department of Environmental Health & Safety #12;Topics in Radiation Safety (applicable RPD Manual sections indicated) User;Topics in Radiation Safety (applicable RPD Manual sections indicated) User and Non-user topics Types

  20. Diffusion processes in general relativistic radiating spheres

    SciTech Connect (OSTI)

    Barreto, W.; Herrera, L.; Santos, N.O. (Oriente Universidad, Cumana (Venezuela); Universidad Central de Venezuela, Caracas; Observatorio Nacional do Brasil, Rio de Janeiro (Brazil))

    1989-09-01T23:59:59.000Z

    The influence of diffusion processes on the dynamics of general relativistic radiating spheres is systematically studied by means of two examples. Differences between the streaming-out limit and the diffusion limit are exhibited, for both models, through the evolution curves of dynamical variables. In particular it is shown the Bondi mass decreases, for both models, in the diffusion limit as compared with its value at the streaming-out regime. 15 refs.

  1. Unilateral radiation pneumonitis in sheep: Physiological changes and bronchoalveolar lavage

    SciTech Connect (OSTI)

    Tillman, B.F.; Loyd, J.E.; Malcolm, A.W.; Holm, B.A.; Brigham, K.L. (Vanderbilt Univ. School of Medicine, Nashville, TN (USA))

    1989-03-01T23:59:59.000Z

    Radiation pneumonitis is a life-threatening result of therapeutic thoracic irradiation, yet its mechanisms are poorly understood. We studied the effects of unilateral lung irradiation (3,000 rad) in sheep from the immediate response to the later development of radiation pneumonitis. We defined radiation pneumonitis by its diagnostic clinical feature, radiographic infiltration of the irradiated zone with a straight margin corresponding to the radiation port. The immediate response in the few hours after irradiation was characterized by cough, labored respiration, hypoxemia (arterial PO{sub 2} decreased 19 Torr), mild pulmonary hypertension (pulmonary arterial pressure increased 20%), and lymphopenia. Hemodynamics and gas exchange returned to normal by day 2 but became abnormal again before or during radiation pneumonitis at 32 +/- 2 days. Respiratory distress, hypoxemia, and pulmonary hypertension recurred during radiation pneumonitis. Bronchoalveolar lavage during radiation pneumonitis contained increased neutrophils (19 +/- 4%, control = 7%), increased protein (0.27 +/- 0.1 g/dl, control = 0.12 +/- 0.03), and severely impaired ability to lower surface tension. Alveolar macrophages from both lungs during unilateral radiation pneumonitis exhibited impaired generation of superoxide after phorbol myristate (only a 30% increase). Normal control alveolar macrophages increased superoxide production after stimulation greater than 400%. We conclude that unilateral lung irradiation in sheep causes a mild immediate response followed by radiation pneumonitis at 1 mo. Unilateral radiation pneumonitis in this model is associated with ipsilateral neutrophilic alveolitis, increased bronchoalveolar lavage protein, and impaired surfactant function, as well as bilateral functional abnormalities of alveolar macrophages.

  2. Radiation delivery system and method

    DOE Patents [OSTI]

    Sorensen, Scott A. (Overland Park, KS); Robison, Thomas W. (Los Alamos, NM); Taylor, Craig M. V. (Jemez Springs, NM)

    2002-01-01T23:59:59.000Z

    A radiation delivery system and method are described. The system includes a treatment configuration such as a stent, balloon catheter, wire, ribbon, or the like, a portion of which is covered with a gold layer. Chemisorbed to the gold layer is a radiation-emitting self-assembled monolayer or a radiation-emitting polymer. The radiation delivery system is compatible with medical catheter-based technologies to provide a therapeutic dose of radiation to a lesion following an angioplasty procedure.

  3. Radiation Protection and Safety Training | Environmental Radiation

    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: National5Sales for4,645U.S. DOE Office of Science (SC)IntegratedSpeedingTechnicalPurchase, Delivery, andSmartRadiation EffectsProtection

  4. Scattering of radiation in collisionless dusty plasmas

    SciTech Connect (OSTI)

    Tolias, P.; Ratynskaia, S. [Space and Plasma Physics, Royal Institute of Technology, Stockholm SE-100 44 (Sweden)

    2013-04-15T23:59:59.000Z

    Scattering of electromagnetic waves in collisionless dusty plasmas is studied in the framework of a multi-component kinetic model. The investigation focuses on the spectral distribution of the scattered radiation. Pronounced dust signatures are identified in the coherent spectrum due to scattering from the shielding cloud around the dust grains, dust acoustic waves, and dust-ion acoustic waves. The magnitude and shape of the scattered signal near these spectral regions are determined with the aid of analytical expressions and its dependence on the dust parameters is investigated. The use of radiation scattering as a potential diagnostic tool for dust detection is discussed.

  5. General Polarization Matrix of Electromagnetic Radiation

    E-Print Network [OSTI]

    Muhammet Ali Can; Alexander S. Shumovsky

    2001-05-15T23:59:59.000Z

    A general form of the polarization matrix valid for any type of electromagnetic radiation (plane waves, multipole radiation etc.) is defined in terms of a certain bilinear form in the field-strength tensor. The quantum counterpart is determined as an operator matrix with normal-ordered elements with respect to the creation and annihilation operators. The zero-point oscillations (ZPO) of polarization are defined via difference between the anti-normal and normal ordered operator polarization matrices. It is shown that ZPO of the multipole field are stronger than those described by the model of plane waves and are concentrated in a certain neighborhood of a local source.

  6. Black Hole Radiation and Volume Statistical Entropy

    E-Print Network [OSTI]

    Mario Rabinowitz

    2005-06-29T23:59:59.000Z

    The simplest possible equation for Hawking radiation, and other black hole radiated power is derived in terms of black hole density. Black hole density also leads to the simplest possible model of a gas of elementary constituents confined inside a gravitational bottle of Schwarzchild radius at tremendous pressure, which yields identically the same functional dependence as the traditional black hole entropy. Variations of Sbh can be obtained which depend on the occupancy of phase space cells. A relation is derived between the constituent momenta and the black hole radius which is similar to the Compton wavelength relation.

  7. Detectable Signatures of Cosmic Radiative Feedback

    E-Print Network [OSTI]

    R. Schneider; R. Salvaterra; T. Roy Choudhury; A. Ferrara; C. Burigana; L. A. Popa

    2007-12-04T23:59:59.000Z

    We use a semi-analytical model to study the impact of reionization, and the associated radiative feedback, on galaxy formation. Two feedback models have been considered: (i) a standard prescription, according to which star formation is totally suppressed in galaxies with circular velocity below a critical threshold (model CF06) and (ii) a characterization based on the filtering scale (model G00), allowing for a gradual reduction of the gas available for star formation in low-mass galaxies. In model CF06 reionization starts at z ~ 15-20, is 85% complete by z ~ 10; at the same z, the ionized fraction is 16% in model G00. The models match SDSS constraints on the evolution of the neutral hydrogen fraction at z feedback models. Deviations among radiative feedback prescriptions emerge when considering the expected HI 21 cm background signal, where a ~ 15 mK absorption feature in the range 75-100 MHz is present in model G00 and a global shift of the emission feature preceding reionization towards larger frequencies occurs in the same model. Single dish observations with existing or forthcoming low-frequency radio telescopes can achieve mK sensitivity, allowing the identification of these features provided that foregrounds can be accurately subtracted.

  8. atmosphere radiation budget: Topics by E-print Network

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

    2D observations of radiative fluxes seems promising for the observational study of extra-solar metrics for the validation of climate models, as asked for by the Intergovernmental...

  9. Introduction Dust aerosols affect visibility, perturb the radiative energy balance

    E-Print Network [OSTI]

    Wang, Jun

    Sunphotometer and air temperature from ground observations. Model Flow Chart GOES-8 06/28/00 1145 UTC -90 -80Introduction Dust aerosols affect visibility, perturb the radiative energy balance of the earth

  10. alpha particles radiative: Topics by E-print Network

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

    rate includes a constant term and a linear term of radiation dose, implying that the damage to some cell nuclei has a time accumulating effect. This model ... Liu, Longjian...

  11. Environmental assessment for the Atmospheric Radiation Measurement (ARM) Program: Southern Great Plains Cloud and Radiation Testbed (CART) site

    SciTech Connect (OSTI)

    Policastro, A.J.; Pfingston, J.M.; Maloney, D.M.; Wasmer, F.; Pentecost, E.D.

    1992-03-01T23:59:59.000Z

    The Atmospheric Radiation Measurement (ARM) Program is aimed at supplying improved predictive capability of climate change, particularly the prediction of cloud-climate feedback. The objective will be achieved by measuring the atmospheric radiation and physical and meteorological quantities that control solar radiation in the earth`s atmosphere and using this information to test global climate and related models. The proposed action is to construct and operate a Cloud and Radiation Testbed (CART) research site in the southern Great Plains as part of the Department of Energy`s Atmospheric Radiation Measurement Program whose objective is to develop an improved predictive capability of global climate change. The purpose of this CART research site in southern Kansas and northern Oklahoma would be to collect meteorological and other scientific information to better characterize the processes controlling radiation transfer on a global scale. Impacts which could result from this facility are described.

  12. Remote radiation dosimetry

    DOE Patents [OSTI]

    Braunlich, P.F.; Tetzlaff, W.; Hegland, J.E.; Jones, S.C.

    1991-03-12T23:59:59.000Z

    Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via a transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission. 8 figures.

  13. Packet personal radiation monitor

    DOE Patents [OSTI]

    Phelps, J.E.

    1988-03-31T23:59:59.000Z

    A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiatonevents, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible ''chirp''. The rate of the ''chirps'' is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field. 2 figs.

  14. Coherent Nuclear Radiation

    E-Print Network [OSTI]

    V. I. Yukalov; E. P. Yukalova

    2004-06-22T23:59:59.000Z

    The main part of this review is devoted to the comprehensive description of coherent radiation by nuclear spins. The theory of nuclear spin superradiance is developed and the experimental observations of this phenomenon are considered. The intriguing problem of how coherence develops from initially incoherent quantum fluctuations is analysed. All main types of coherent radiation by nuclear spins are discussed, which are: free nuclear induction, collective induction, maser generation, pure superradiance, triggered superradiance, pulsing superradiance, punctuated superradiance, and induced emission. The influence of electron-nuclear hyperfine interactions and the role of magnetic anisotropy are studied. Conditions for realizing spin superradiance by magnetic molecules are investigated. The possibility of nuclear matter lasing, accompanied by pion or dibaryon radiation, is briefly touched.

  15. Pediatric radiation oncology

    SciTech Connect (OSTI)

    Halperin, E.C.; Kun, L.E.; Constine, L.S.; Tarbell, N.J.

    1989-01-01T23:59:59.000Z

    This text covers all aspects of radiation therapy for treatment of pediatric cancer. The book describes the proper use of irradiation in each of the malignancies of childhood, including tumors that are rarely encountered in adult practice. These include acute leukemia; supratentorial brain tumors; tumors of the posterior fossa of the brain and spinal canal; retinoblastoma and optic nerve glioma; neuroblastoma; Hodgkin's disease; malignant lymphoma; Ewing's sarcoma; osteosarcoma; rhabdomyosarcoma; Desmoid tumor; Wilms' tumor; liver and biliary tumors; germ cell and stromal cell tumors of the gonads; endocrine, aerodigestive tract, and breast tumors; Langerhans' cell histiocytosis; and skin cancer and hemangiomas. For each type of malignancy, the authors describe the epidemiology, common presenting signs and symptoms, staging, and proper diagnostic workup. Particular attention is given to the indications for radiation therapy and the planning of a course of radiotherapy, including the optimal radiation dose, field size, and technique.

  16. Composition for radiation shielding

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-08-02T23:59:59.000Z

    A composition for use as a radiation shield is disclosed. The shield has a depleted uranium core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container. 2 figs.

  17. Virial theorem for radiating accretion discs

    E-Print Network [OSTI]

    Patryk Mach

    2012-04-18T23:59:59.000Z

    A continuum version of the virial theorem is derived for a radiating self-gravitating accretion disc around a compact object. The central object is point-like, but we can avoid the regularization of its gravitational potential. This is achieved by applying a modified Pohozaev-Rellich identity to the gravitational potential of the disk only. The theorem holds for general stationary configurations, including discontinuous flows (shock waves, contact discontinuities). It is used to test numerical solutions of a model of self-gravitating radiative accretion discs. The presented virial theorem should be useful in the analysis of those (possibly radiating) hydrodynamical systems in astrophysics where the central mass and the mass of the fluid are comparable and none of them can be neglected.

  18. Tropical Cloud Properties and Radiative Heating Profiles

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mather, James

    We have generated a suite of products that includes merged soundings, cloud microphysics, and radiative fluxes and heating profiles. The cloud microphysics is strongly based on the ARM Microbase value added product (Miller et al., 2003). We have made a few changes to the microbase parameterizations to address issues we observed in our initial analysis of the tropical data. The merged sounding product is not directly related to the product developed by ARM but is similar in that it uses the microwave radiometer to scale the radiosonde column water vapor. The radiative fluxes also differ from the ARM BBHRP (Broadband Heating Rate Profile) product in terms of the radiative transfer model and the sampling interval.

  19. Analytical and experimental determination of radiation and temperature distributions inside solar receivers

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    concentrated solar radiation is modelized, using the diffuse and semi-gray surface hypothesis and the net absorptance for solar radiation. Theoretical thermal efficiency of the cavity. Surface hemispherical emittance PHYSIQUE APPLIQU�E - TS, N° 2, F�VRIER1980 Incident solar flux density. Net radiative flux density. Net

  20. Application of three-dimensional solar radiative transfer to mountains Y. Chen,1,2

    E-Print Network [OSTI]

    Liou, K. N.

    Application of three-dimensional solar radiative transfer to mountains Y. Chen,1,2 A. Hall,1 and K November 2006. [1] We developed a three-dimensional radiative transfer model simulating solar fluxes over (2006), Application of three-dimensional solar radiative transfer to mountains, J. Geophys. Res., 111, D

  1. Regular PaperJ. Radiat. Res., 51, 657664 (2010) Adaptive Response in Zebrafish Embryos Induced Using

    E-Print Network [OSTI]

    Yu, K.N.

    2010-01-01T23:59:59.000Z

    in the zebrafish embryos in vivo. INTRODUCTION For radiation protection purposes, prediction of risk from this model is commonly adopted for radiation protection purposes, there is a considerable amount of evidenceRegular PaperJ. Radiat. Res., 51, 657­664 (2010) Adaptive Response in Zebrafish Embryos Induced

  2. Effects of exogenous carbon monoxide on radiation-induced bystander effect in zebrafish embryos in vivo

    E-Print Network [OSTI]

    Yu, K.N.

    -no-threshed (LNT) model widely accepted for radiation protection saying that biological effects caused by ionizingEffects of exogenous carbon monoxide on radiation-induced bystander effect in zebrafish embryos) on the radiation induced bystander effect (RIBE) in vivo between embryos of the zebrafish was studied. RIBE

  3. Radiation Detection Scenario Analysis Toolbox (RADSAT) Test Case Implementation Final Report

    SciTech Connect (OSTI)

    Shaver, Mark W.

    2010-09-27T23:59:59.000Z

    Final report for the project. This project was designed to demonstrate the use of the Radiation Detection Scenario Analysis Toolbox (RADSAT) radiation detection transport modeling package (developed in a previous NA-22 project) for specific radiation detection scenarios important to proliferation detection.

  4. Evaluation of satellite and reanalysis products of downward surface solar radiation over East Asia: Spatial and

    E-Print Network [OSTI]

    Dai, Aiguo

    Evaluation of satellite and reanalysis products of downward surface solar radiation over East Asia Received 29 July 2012; revised 27 February 2013; accepted 18 March 2013. [1] Surface solar radiation plays hydrological models. In this study, the downward surface solar radiation (DSSR) from two satellite products

  5. 2008 European PV Conference, Valencia, Spain COMPARISON OF SOLAR RADIATION FORECASTS FOR THE USA

    E-Print Network [OSTI]

    Perez, Richard R.

    2008 European PV Conference, Valencia, Spain COMPARISON OF SOLAR RADIATION FORECASTS FOR THE USA J models 1 INTRODUCTION Solar radiation and PV production forecasts are becoming increasingly important/) three teams of experts are benchmarking their solar radiation forecast against ground truth data

  6. Radiation damage calculation in PHITS Y. Iwamoto1, K. Niita2, T. Sawai1,

    E-Print Network [OSTI]

    McDonald, Kirk

    Radiation damage calculation in PHITS 1 Y. Iwamoto1, K. Niita2, T. Sawai1, R.M. Ronningen3, T Feb. ­ 15 Feb. 2012 #12;2 Introduction Radiation damage model in PHITS Radiation damage calculation As the power of proton and heavy-ion accelerators is increasing, the prediction of the structural damage

  7. SURFACE CLOUD RADIATIVE FORCING, CLOUD FRACTION AND CLOUD ALBEDO: THEIR RELATIONSHIP AND MULTISCALE VARIATION

    E-Print Network [OSTI]

    that have been used to quantify the effect of clouds on radiation budget in both modeling and observationalSURFACE CLOUD RADIATIVE FORCING, CLOUD FRACTION AND CLOUD ALBEDO: THEIR RELATIONSHIP AND MULTISCALE/Atmospheric Sciences Division Brookhaven National Laboratory P.O. Box, Upton, NY www.bnl.gov ABSTRACT Cloud-radiation

  8. Spectral brilliance of channeling radiation at the ASTA photoinjector

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

    Sen, Tanaji [Fermi National Accelerator Lab., Batavia, IL (United States); Lynn, Christopher [Swarthmore College, Swarthmore, PA (United States)

    2014-12-10T23:59:59.000Z

    We study channeling radiation from electron beams with energies under 100 MeV. We introduce a phenomenological model of dechanneling, correct non-radiative transition rates from thermal scattering, and discuss in detail the population dynamics in low order bound states. These are used to revisit the X-ray properties measured at the ELBE facility in Forschungszentrum Dresden-Rosenstock (FZDR), extract parameters for dechanneling states, and obtain satisfactory agreement with measured photon yields. The importance of rechanneling phenomena in thick crystals is emphasized. The model is then used to calculate the expected X-ray energies, linewidths and brilliance for forthcoming channeling radiation experiments at Fermilab's ASTA photoinjector.

  9. Spectral brilliance of channeling radiation at the ASTA photoinjector

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

    Sen, Tanaji; Lynn, Christopher

    2014-12-10T23:59:59.000Z

    We study channeling radiation from electron beams with energies under 100 MeV. We introduce a phenomenological model of dechanneling, correct non-radiative transition rates from thermal scattering, and discuss in detail the population dynamics in low order bound states. These are used to revisit the X-ray properties measured at the ELBE facility in Forschungszentrum Dresden-Rosenstock (FZDR), extract parameters for dechanneling states, and obtain satisfactory agreement with measured photon yields. The importance of rechanneling phenomena in thick crystals is emphasized. The model is then used to calculate the expected X-ray energies, linewidths and brilliance for forthcoming channeling radiation experiments at Fermilab's ASTAmore »photoinjector.« less

  10. Radiation monitor for liquids

    DOE Patents [OSTI]

    Koster, J.E.; Bolton, R.D.

    1999-03-02T23:59:59.000Z

    A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans. 4 figs.

  11. Radiation monitor for liquids

    DOE Patents [OSTI]

    Koster, James E. (Los Alamos, NM); Bolton, Richard D. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans.

  12. Wireless passive radiation sensor

    DOE Patents [OSTI]

    Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J

    2013-12-03T23:59:59.000Z

    A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.

  13. Radiation.cdr

    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: National5Sales for4,645U.S. DOE Office of Science (SC)IntegratedSpeedingTechnicalPurchase, Delivery, andSmartRadiationRadiation Safety Work

  14. Dark Radiation in Anisotropic LARGE Volume Compactifications

    E-Print Network [OSTI]

    Stephen Angus

    2014-10-30T23:59:59.000Z

    Dark radiation is a compelling extension to $\\Lambda$CDM: current experimental results hint at $\\Delta N_{\\rm eff} \\gtrsim 0.5$, which is increased to $\\Delta N_{\\rm eff} \\simeq 1$ if the recent BICEP2 results are included. In recent years dark radiation has been considered in the context of string theory models such as the LARGE Volume Scenario of type IIB string theory, forging a link between present-day cosmological observations and models of physics at the Planck scale. In this paper I consider an extension of the LARGE Volume Scenario in which the bulk volume is stabilised by two moduli instead of one. Consequently, the lightest modulus no longer corresponds to the compactification volume but instead to a transverse direction in the bulk geometry. I focus on scenarios in which sequestering of soft masses is achieved by localising the Standard Model on D3 branes at a singularity. The fraction of dark radiation produced in such models vastly exceeds experimental bounds, ruling out the sequestered LARGE Volume Scenario with two bulk moduli as a model of the early Universe.

  15. Direct radiative forcing due to aerosols in Asia during Soon-Ung Parka,, Jaein I. Jeongb

    E-Print Network [OSTI]

    Park, Rokjin

    Direct radiative forcing due to aerosols in Asia during March 2002 Soon-Ung Parka,, Jaein I. Jeongb Model (CRM) of Community Climate Model 3 and the output of the fifth generation of meso-scale model (MM5 in the global climate system by changing atmospheric radiation balance (Tegen and Fung, 1994; Andreae, 1996; Li

  16. Method of controlling coherent synchroton radiation-driven degradation of beam quality during bunch length compression

    DOE Patents [OSTI]

    Douglas, David R. (Newport News, VA); Tennant, Christopher D. (Williamsburg, VA)

    2012-07-10T23:59:59.000Z

    A method of avoiding CSR induced beam quality defects in free electron laser operation by a) controlling the rate of compression and b) using a novel means of integrating the compression with the remainder of the transport system: both are accomplished by means of dispersion modulation. A large dispersion is created in the penultimate dipole magnet of the compression region leading to rapid compression; this large dispersion is demagnified and dispersion suppression performed in a final small dipole. As a result, the bunch is short for only a small angular extent of the transport, and the resulting CSR excitation is small.

  17. Local microwave background radiation

    E-Print Network [OSTI]

    Domingos Soares

    2014-11-13T23:59:59.000Z

    An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

  18. Radiation Source Replacement Workshop

    SciTech Connect (OSTI)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01T23:59:59.000Z

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  19. Thermostatic Radiator Valve Evaluation

    SciTech Connect (OSTI)

    Dentz, Jordan [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States); Ansanelli, Eric [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States)

    2015-01-01T23:59:59.000Z

    A large stock of multifamily buildings in the Northeast and Midwest are heated by steam distribution systems. Losses from these systems are typically high and a significant number of apartments are overheated much of the time. Thermostatically controlled radiator valves (TRVs) are one potential strategy to combat this problem, but have not been widely accepted by the residential retrofit market.

  20. Three Dimensional Radiative Transfer

    E-Print Network [OSTI]

    Tom Abel

    2000-05-09T23:59:59.000Z

    Radiative Transfer (RT) effects play a crucial role in the thermal history of the intergalactic medium. Here I discuss recent advances in the development of numerical methods that introduce RT to cosmological hydrodynamics. These methods can also readily be applied to time dependent problems on interstellar and galactic scales.

  1. Radiation detector spectrum simulator

    DOE Patents [OSTI]

    Wolf, M.A.; Crowell, J.M.

    1985-04-09T23:59:59.000Z

    A small battery operated nuclear spectrum simulator having a noise source generates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith to generate several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  2. Photovoltaic radiation detector element

    DOE Patents [OSTI]

    Agouridis, D.C.

    1980-12-17T23:59:59.000Z

    A radiation detector element is formed of a body of semiconductor material, a coating on the body which forms a photovoltaic junction therewith, and a current collector consisting of narrow metallic strips, the aforesaid coating having an opening therein in the edge of which closely approaches but is spaced from the current collector strips.

  3. Radiation Characteristics of Glass Containing Gas Bubbles

    E-Print Network [OSTI]

    Pilon, Laurent; Viskanta, Raymond

    2003-01-01T23:59:59.000Z

    B. L. Drolen, “Thermal radiation in particulate media withRadiation Characteristics of Glass Containing Gas Bubblesthermophysical properties and radiation characteristics of

  4. Radiation damage evolution in ceramics. | EMSL

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

    Radiation damage evolution in ceramics. Radiation damage evolution in ceramics. Abstract: A review is presented of recent results on radiation damage production, defect...

  5. Preliminary radiation shielding design for BOOMERANG

    E-Print Network [OSTI]

    Donahue, Richard J.

    2002-01-01T23:59:59.000Z

    Preliminary Radiation Shielding Design for BOOMERANG R. J.2003 Abstract Preliminary radiation shielding speci?cationsElectron Photon Stray Radiation from a High Energy Electron

  6. Terahertz radiation from laser accelerated electron bunches

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    NUMBER 5 MAY 2004 Terahertz radiation from laser acceleratedand millimeter wave radiation from laser acceleratedNo. 5, May 2004 Terahertz radiation from laser accelerated

  7. Meeting Report--NASA Radiation Biomarker Workshop

    E-Print Network [OSTI]

    Straume, Tore

    2008-01-01T23:59:59.000Z

    ionizing radiation. In: Advances in Medical Physics (A. B.for medical management of radiation casualties. ADVANCES INMedical Center presented the radiation oncology perspective on biomarkers. Advances

  8. Nanoscale Engineering Of Radiation Tolerant Silicon Carbide....

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

    Engineering Of Radiation Tolerant Silicon Carbide. Nanoscale Engineering Of Radiation Tolerant Silicon Carbide. Abstract: Radiation tolerance is determined by how effectively the...

  9. Radiation Safety Training Basic Radiation Safety Training for

    E-Print Network [OSTI]

    Dai, Pengcheng

    Radiation Safety Training Basic Radiation Safety Training for Sealed Source Users for Physics 461 Protocol Title: Training for Sealed Source Users Drafted By: Chris Millsaps, RSS Reviewers: ZB, TU, GS Purpose: To provide basic radiation safety training to the users of sealed sources located

  10. Radiation reaction for multipole moments

    E-Print Network [OSTI]

    P. O. Kazinski

    2006-04-27T23:59:59.000Z

    We propose a Poincare-invariant description for the effective dynamics of systems of charged particles by means of intrinsic multipole moments. To achieve this goal we study the effective dynamics of such systems within two frameworks -- the particle itself and hydrodynamical one. We give a relativistic-invariant definition for the intrinsic multipole moments both pointlike and extended relativistic objects. Within the hydrodynamical framework we suggest a covariant action functional for a perfect fluid with pressure. In the case of a relativistic charged dust we prove the equivalence of the particle approach to the hydrodynamical one to the problem of radiation reaction for multipoles. As the particular example of a general procedure we obtain the effective model for a neutral system of charged particles with dipole moment.

  11. Pacific Northwest Solar Radiation Data

    E-Print Network [OSTI]

    Oregon, University of

    Pacific Northwest Solar Radiation Data UO SOLAR MONITORING LAB Physics Department -- Solar Energy Center 1274 University of Oregon Eugene, Oregon 97403-1274 April 1, 1999 #12;Hourly solar radiation data

  12. RADIATION DAMAGE OF GERMANIUM DETECTORS

    E-Print Network [OSTI]

    Pehl, Richard H.

    2011-01-01T23:59:59.000Z

    the high-energy proton damage than was the planar detector.as far as radiation damage is concerned. Unfortunately, some28-29, 1978 LBL-7967 RADIATION DAMAGE OF GERMANIUM DETECTORS

  13. A concept for Z-dependent microbunching measurements with coherent X-ray transition radiation in a sase FEL

    E-Print Network [OSTI]

    Lumpkin, A.H.; Fawley, W.M.; Rule, D.W.

    2004-01-01T23:59:59.000Z

    Model to Data from a SASE FEL at 540, 265, and 157 nm,”simulation of the x-ray SASE FEL showing the SASE radiationTRANSITION RADIATION IN A SASE FEL* A.H. Lumpkin # , W.M.

  14. Parameterization and Analysis of 3-D Solar Radiative Transfer in Clouds: Final Report

    SciTech Connect (OSTI)

    Jerry Y. Harrington

    2012-09-21T23:59:59.000Z

    This document reports on the research that we have done over the course of our two-year project. The report also covers the research done on this project during a 1 year no-cost extension of the grant. Our work has had two main, inter-related thrusts: The first thrust was to characterize the response of stratocumulus cloud structure and dynamics to systematic changes in cloud infrared radiative cooling and solar heating using one-dimensional radiative transfer models. The second was to couple a three-dimensional (3-D) solar radiative transfer model to the Large Eddy Simulation (LES) model that we use to simulate stratocumulus. The purpose of the studies with 3-D radiative transfer was to examine the possible influences of 3-D photon transport on the structure, evolution, and radiative properties of stratocumulus. While 3-D radiative transport has been examined in static cloud environments, few studies have attempted to examine whether the 3-D nature of radiative absorption and emission influence the structure and evolution of stratocumulus. We undertook this dual approach because only a small number of LES simulations with the 3-D radiative transfer model are possible due to the high computational costs. Consequently, LES simulations with a 1-D radiative transfer solver were used in order to examine the portions of stratocumulus parameter space that may be most sensitive to perturbations in the radiative fields. The goal was then to explore these sensitive regions with LES using full 3-D radiative transfer. Our overall goal was to discover whether 3-D radiative processes alter cloud structure and evolution, and whether this may have any indirect implications for cloud radiative properties. In addition, we collaborated with Dr. Tamas Varni, providing model output fields for his attempt at parameterizing 3-D radiative effects for cloud models.

  15. DOE Radiation Records Contacts List

    Broader source: Energy.gov [DOE]

    DOE radiation records contact list for individuals to obtain records of occupational exposure directly from a DOE site.

  16. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1994-08-16T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  17. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  18. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1995-10-17T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  19. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  20. NCSRNCSR ""DEMOKRITOSDEMOKRITOS"" INSTITUTE OF NUCLEAR TECHNOLOGY & RADIATION PROTECTIONINSTITUTE OF NUCLEAR TECHNOLOGY & RADIATION PROTECTION

    E-Print Network [OSTI]

    PROTECTIONINSTITUTE OF NUCLEAR TECHNOLOGY & RADIATION PROTECTION ·· ENVIRONMENTAL RESEARCH LABORATORYENVIRONMENTAL·· NCSRNCSR ""DEMOKRITOSDEMOKRITOS"" ·· INSTITUTE OF NUCLEAR TECHNOLOGY & RADIATION

  1. Original article Measurement and modelling of radiation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    (Diawara, 1990) that the trunks have almost no effect on heat and mass exchange. The leaf area index (LAI

  2. COLUMBIA UNIVERSITY Radiation Safety Program

    E-Print Network [OSTI]

    Jia, Songtao

    COLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212-305-0303 F: 212-305-0318 rso-clinical@columbia by more than 50 percent. #12;COLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212 ________________________________________________________ ________________________________________________________ #12;COLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212-305-0303 F: 212-305-0318 rso-clinical@columbia

  3. 6, 52315250, 2006 Radiative properties

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the short- wave (SW) and longwave (LW) cloud radiative effects (CRE), but the impact is small: 0.02 W m-2 tests are conducted to evaluate the impact that5 such an over-layer would have on the radiative effects, terrestrial) radiation. The SW "albedo" effect brings about cooling and the LW "greenhouse" effect warming

  4. 2007 Radiation & Climate GRC ( July 29-August 3, 2007)

    SciTech Connect (OSTI)

    William Collins

    2008-06-01T23:59:59.000Z

    The theme of the fifth Gordon Research Conference on Radiation and Climate is 'Integrating multiscale measurements and models for key climate questions'. The meeting will feature lectures, posters, and discussion regarding these issues. The meeting will focus on insights from new types of satellite and in situ data and from new approaches to modeling processes in the climate system. The program on measurements will highlight syntheses of new satellite data on cloud, aerosols, and chemistry and syntheses of satellite and sub-orbital observations from field programs. The program on modeling will address both the evaluation of cloud-resolving and regional aerosol models using new types of measurements and the evidence for processes and physics missing from global models. The Conference will focus on two key climate questions. First, what factors govern the radiative interactions of clouds and aerosols with regional and global climate? Second, how well do we understand the interaction of radiation with land surfaces and with the cryosphere?

  5. Progress Toward an Updated National Solar Radiation Data Base

    SciTech Connect (OSTI)

    Wilcox, S.; Anderberg, M.; George, R.; Marion, W.; Myers, D.; Renne, D.; Beckman, W.; DeGaetano, A.; Gueymard, C.; Perez, R.; Plantico, M.; Stackhouse, P.; Vignola, F.

    2005-01-01T23:59:59.000Z

    Progress is reported on an updated National Solar Radiation Database (NSRDB). Focus on this year's work was on preparing a test-year database for evaluating several solar radiation models that could be used to replace the METSTAT model used in the original 1961-1990 NSRDB. That model is no longer compatible with cloud observations reported by the National Weather Service. We have also included a satellite-based model that will increase the spatial resolution of solar radiation for GIS or mapping applications. Work also included development of improved estimates for aerosols, water vapor, and ozone. High-quality solar measurements were obtained for 33 sites near National Weather Service stations, and model runs were completed for test years 1999 and 2000.

  6. Radiation-induced mechanical property changes in filled rubber

    SciTech Connect (OSTI)

    Maiti, A.; Weisgraber, T. H.; Gee, R. H.; Small, W.; Alviso, C. T.; Chinn, S. C.; Maxwell, R. S. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2011-06-15T23:59:59.000Z

    In a recent paper we exposed a filled elastomer to controlled radiation dosages and explored changes in its cross-link density and molecular weight distribution between network junctions [A. Maiti et al., Phys. Rev. E 83, 031802 (2011)]. Here we report mechanical response measurements when the material is exposed to radiation while being under finite nonzero strain. We observe interesting hysteretic behavior and material softening representative of the Mullins effect, and materials hardening due to radiation. The net magnitude of the elastic modulus depends upon the radiation dosage, strain level, and strain-cycling history of the material. Using the framework of Tobolsky's two-stage independent network theory we develop a model that can quantitatively interpret the observed elastic modulus and its radiation and strain dependence.

  7. Terahertz radiation mixer

    DOE Patents [OSTI]

    Wanke, Michael C. (Albuquerque, NM); Allen, S. James (Santa Barbara, CA); Lee, Mark (Albuquerque, NM)

    2008-05-20T23:59:59.000Z

    A terahertz radiation mixer comprises a heterodyned field-effect transistor (FET) having a high electron mobility heterostructure that provides a gatable two-dimensional electron gas in the channel region of the FET. The mixer can operate in either a broadband pinch-off mode or a narrowband resonant plasmon mode by changing a grating gate bias of the FET. The mixer can beat an RF signal frequency against a local oscillator frequency to generate an intermediate frequency difference signal in the microwave region. The mixer can have a low local oscillator power requirement and a large intermediate frequency bandwidth. The terahertz radiation mixer is particularly useful for terahertz applications requiring high resolution.

  8. National Ambient Radiation Database

    SciTech Connect (OSTI)

    Dziuban, J.; Sears, R.

    2003-02-25T23:59:59.000Z

    The U.S. Environmental Protection Agency (EPA) recently developed a searchable database and website for the Environmental Radiation Ambient Monitoring System (ERAMS) data. This site contains nationwide radiation monitoring data for air particulates, precipitation, drinking water, surface water and pasteurized milk. This site provides location-specific as well as national information on environmental radioactivity across several media. It provides high quality data for assessing public exposure and environmental impacts resulting from nuclear emergencies and provides baseline data during routine conditions. The database and website are accessible at www.epa.gov/enviro/. This site contains (1) a query for the general public which is easy to use--limits the amount of information provided, but includes the ability to graph the data with risk benchmarks and (2) a query for a more technical user which allows access to all of the data in the database, (3) background information on ER AMS.

  9. Time encoded radiation imaging

    DOE Patents [OSTI]

    Marleau, Peter; Brubaker, Erik; Kiff, Scott

    2014-10-21T23:59:59.000Z

    The various technologies presented herein relate to detecting nuclear material at a large stand-off distance. An imaging system is presented which can detect nuclear material by utilizing time encoded imaging relating to maximum and minimum radiation particle counts rates. The imaging system is integrated with a data acquisition system that can utilize variations in photon pulse shape to discriminate between neutron and gamma-ray interactions. Modulation in the detected neutron count rates as a function of the angular orientation of the detector due to attenuation of neighboring detectors is utilized to reconstruct the neutron source distribution over 360 degrees around the imaging system. Neutrons (e.g., fast neutrons) and/or gamma-rays are incident upon scintillation material in the imager, the photons generated by the scintillation material are converted to electrical energy from which the respective neutrons/gamma rays can be determined and, accordingly, a direction to, and the location of, a radiation source identified.

  10. Radiation shielding composition

    DOE Patents [OSTI]

    Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

    2000-12-26T23:59:59.000Z

    A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.

  11. Semiconductor radiation detector

    DOE Patents [OSTI]

    Patt, Bradley E. (Sherman Oaks, CA); Iwanczyk, Jan S. (Los Angeles, CA); Tull, Carolyn R. (Orinda, CA); Vilkelis, Gintas (Westlake Village, CA)

    2002-01-01T23:59:59.000Z

    A semiconductor radiation detector is provided to detect x-ray and light photons. The entrance electrode is segmented by using variable doping concentrations. Further, the entrance electrode is physically segmented by inserting n+ regions between p+ regions. The p+ regions and the n+ regions are individually biased. The detector elements can be used in an array, and the p+ regions and the n+ regions can be biased by applying potential at a single point. The back side of the semiconductor radiation detector has an n+ anode for collecting created charges and a number of p+ cathodes. Biased n+ inserts can be placed between the p+ cathodes, and an internal resistor divider can be used to bias the n+ inserts as well as the p+ cathodes. A polysilicon spiral guard can be implemented surrounding the active area of the entrance electrode or surrounding an array of entrance electrodes.

  12. Radiation shielding composition

    DOE Patents [OSTI]

    Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

    1998-01-01T23:59:59.000Z

    A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.

  13. Radiation shielding composition

    DOE Patents [OSTI]

    Quapp, W.J.; Lessing, P.A.

    1998-07-28T23:59:59.000Z

    A composition is disclosed for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm{sup 3} and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile. 5 figs.

  14. Multilayer radiation shield

    DOE Patents [OSTI]

    Urbahn, John Arthur (Saratoga Springs, NY); Laskaris, Evangelos Trifon (Niskayuna, NY)

    2009-06-16T23:59:59.000Z

    A power generation system including: a generator including a rotor including a superconductive rotor coil coupled to a rotatable shaft; a first prime mover drivingly coupled to the rotatable shaft; and a thermal radiation shield, partially surrounding the rotor coil, including at least a first sheet and a second sheet spaced apart from the first sheet by centripetal force produced by the rotatable shaft. A thermal radiation shield for a generator including a rotor including a super-conductive rotor coil including: a first sheet having at least one surface formed from a low emissivity material; and at least one additional sheet having at least one surface formed from a low emissivity material spaced apart from the first sheet by centripetal force produced by the rotatable shaft, wherein each successive sheet is an incrementally greater circumferential arc length and wherein the centripetal force shapes the sheets into a substantially catenary shape.

  15. Handheld CZT radiation detector

    DOE Patents [OSTI]

    Murray, William S.; Butterfield, Kenneth B.; Baird, William

    2004-08-24T23:59:59.000Z

    A handheld CZT radiation detector having a CZT gamma-ray sensor, a multichannel analyzer, a fuzzy-logic component, and a display component is disclosed. The CZT gamma-ray sensor may be a coplanar grid CZT gamma-ray sensor, which provides high-quality gamma-ray analysis at a wide range of operating temperatures. The multichannel analyzer categorizes pulses produce by the CZT gamma-ray sensor into channels (discrete energy levels), resulting in pulse height data. The fuzzy-logic component analyzes the pulse height data and produces a ranked listing of radioisotopes. The fuzzy-logic component is flexible and well-suited to in-field analysis of radioisotopes. The display component may be a personal data assistant, which provides a user-friendly method of interacting with the detector. In addition, the radiation detector may be equipped with a neutron sensor to provide an enhanced mechanism of sensing radioactive materials.

  16. Training For Radiation Emergencies, First Responder Operations...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Training For Radiation Emergencies, First Responder Operations - Instructors Guide Training For Radiation Emergencies, First Responder Operations - Instructors Guide COURSE...

  17. POLARIZATION OF THE COSMIC BACKGROUND RADIATION

    E-Print Network [OSTI]

    Lubin, Philip Lubin

    2010-01-01T23:59:59.000Z

    a 45° angle. Radiation whose electric field (polarization)radiation field, it can be uniquely characterized by its electric

  18. Global aspects of radiation memory

    E-Print Network [OSTI]

    J. Winicour

    2014-10-11T23:59:59.000Z

    Gravitational radiation has a memory effect represented by a net change in the relative positions of test particles. Both the linear and nonlinear sources proposed for this radiation memory are of the "electric" type, or E mode, as characterized by the even parity of the polarization pattern. Although "magnetic" type, or B mode, radiation memory is mathematically possible, no physically realistic source has been identified. There is an electromagnetic counterpart to radiation memory in which the velocity of charged particles obtain a net "kick". Again, the physically realistic sources of electromagnetic radiation memory that have been identified are of the electric type. In this paper, a global null cone description of the electromagnetic field is applied to establish the non-existence of B mode radiation memory and the non-existence of E mode radiation memory due to a bound charge distribution.

  19. 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

  20. Influences of atmospheric conditions and air mass on the ratio of ultraviolet to total solar radiation

    SciTech Connect (OSTI)

    Riordan, C.J.; Hulstrom, R.L.; Myers, D.R.

    1990-08-01T23:59:59.000Z

    The technology to detoxify hazardous wastes using ultraviolet (UV) solar radiation is being investigated by the DOE/SERI Solar Thermal Technology Program. One of the elements of the technology evaluation is the assessment and characterization of UV solar radiation resources available for detoxification processes. This report describes the major atmospheric variables that determine the amount of UV solar radiation at the earth's surface, and how the ratio of UV-to-total solar radiation varies with atmospheric conditions. These ratios are calculated from broadband and spectral solar radiation measurements acquired at SERI, and obtained from the literature on modeled and measured UV solar radiation. The following sections discuss the atmospheric effects on UV solar radiation and provide UV-to-total solar radiation ratios from published studies, as well as measured values from SERI's data. A summary and conclusions are also given.

  1. Planets and X-rays: a radiation diet

    E-Print Network [OSTI]

    Sanz-Forcada, J; Micela, G; Pollock, A; Garcia-Alvarez, D; Solano, E; Eiroa, C

    2011-01-01T23:59:59.000Z

    According to theory, high energy emission from the coronae of cool stars can severely erode the atmosphere of orbiting planets. To test the long term effects of the erosion we study a large sample of planet-hosting stars observed in X-rays. The results reveal that massive planets (Mp sin i > 1.5 Mj) may survive only if exposed to low accumulated coronal radiation. The planet HD 209458 b might have lost more than 1 Mj already, and other cases, like tau Boo b, could be losing mass at a rate of 3.4 Earth masses per Gyr. The strongest erosive effects would take place during the first stages of the stellar life, when the faster rotation generates more energetic coronal radiation. The planets with higher density seem to resist better the radiation effects, as foreseen by models. Current models need to be improved to explain the observed distribution of planetary masses with the coronal radiation received.

  2. NREL Solar Radiation Resource Assessment Project: Status and outlook

    SciTech Connect (OSTI)

    Renne, D.; Riordan, C.; Maxwell, E.; Stoffel, T.; Marion, B.; Rymes, M.; Wilcox, S.; Myers, D.

    1992-05-01T23:59:59.000Z

    This report summarizes the activities and accomplishments of NREL's Solar Radiation Resource Assessment Project during fiscal year 1991. Currently, the primary focus of the SRRAP is to produce a 1961--1990 National Solar Radiation Data Base, providing hourly values of global horizontal, diffuse, and direct normal solar radiation at approximately 250 sites around the United States. Because these solar radiation quantities have been measured intermittently at only about 50 of these sites, models were developed and applied to the majority of the stations to provide estimates of these parameters. Although approximately 93% of the data base consists of modeled data this represents a significant improvement over the SOLMET/ERSATZ 1952--1975 data base. The magnitude and importance of this activity are such that the majority of SRRAP human and financial in many other activities, which are reported here. These include the continued maintenance of a solar radiation monitoring network in the southeast United States at six Historically Black Colleges and Universities (HBCU's), the transfer of solar radiation resource assessment technology through a variety of activities, participation in international programs, and the maintenance and operation of NREL's Solar Radiation Research Laboratory. 17 refs.

  3. LIFETIME PREDICTION FOR MODEL 9975 O-RINGS IN KAMS

    SciTech Connect (OSTI)

    Hoffman, E.; Skidmore, E.

    2009-11-24T23:59:59.000Z

    The Savannah River Site (SRS) is currently storing plutonium materials in the K-Area Materials Storage (KAMS) facility. The materials are packaged per the DOE 3013 Standard and transported and stored in KAMS in Model 9975 shipping packages, which include double containment vessels sealed with dual O-rings made of Parker Seals compound V0835-75 (based on Viton{reg_sign} GLT). The outer O-ring of each containment vessel is credited for leaktight containment per ANSI N14.5. O-ring service life depends on many factors, including the failure criterion, environmental conditions, overall design, fabrication quality and assembly practices. A preliminary life prediction model has been developed for the V0835-75 O-rings in KAMS. The conservative model is based primarily on long-term compression stress relaxation (CSR) experiments and Arrhenius accelerated-aging methodology. For model development purposes, seal lifetime is defined as a 90% loss of measurable sealing force. Thus far, CSR experiments have only reached this target level of degradation at temperatures {ge} 300 F. At lower temperatures, relaxation values are more tolerable. Using time-temperature superposition principles, the conservative model predicts a service life of approximately 20-25 years at a constant seal temperature of 175 F. This represents a maximum payload package at a constant ambient temperature of 104 F, the highest recorded in KAMS to date. This is considered a highly conservative value as such ambient temperatures are only reached on occasion and for short durations. The presence of fiberboard in the package minimizes the impact of such temperature swings, with many hours to several days required for seal temperatures to respond proportionately. At 85 F ambient, a more realistic but still conservative value, bounding seal temperatures are reduced to {approx}158 F, with an estimated seal lifetime of {approx}35-45 years. The actual service life for O-rings in a maximum wattage package likely lies higher than the estimates due to the conservative assumptions used for the model. For lower heat loads at similar ambient temperatures, seal lifetime is further increased. The preliminary model is based on several assumptions that require validation with additional experiments and longer exposures at more realistic conditions. The assumption of constant exposure at peak temperature is believed to be conservative. Cumulative damage at more realistic conditions will likely be less severe but is more difficult to assess based on available data. Arrhenius aging behavior is expected, but non-Arrhenius behavior is possible. Validation of Arrhenius behavior is ideally determined from longer tests at temperatures closer to actual service conditions. CSR experiments will therefore continue at lower temperatures to validate the model. Ultrasensitive oxygen consumption analysis has been shown to be useful in identifying non-Arrhenius behavior within reasonable test periods. Therefore, additional experiments are recommended and planned to validate the model.

  4. T violation in radiative $\\beta$ decay and electric dipole moments

    E-Print Network [OSTI]

    Dekens, W G

    2015-01-01T23:59:59.000Z

    In radiative $\\beta$ decay, $T$ violation can be studied through a spin-independent $T$-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM) sources of $T$-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs). As a consequence, the manifestations of the $T$-odd BSM physics in radiative $\\beta$ decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent $T$-odd correlation in radiative $\\beta$ decay.

  5. THz near-field imaging of biological tissues employing synchrotron radiation

    E-Print Network [OSTI]

    ¨ur Synchrotronstrahlung mbH (BESSY), Albert-Einstein-Straße 15, 12489 Berlin, Germany; bAdvanced Light Source Division CSR source at BESSY3, 5 we have been able to extend traditional infrared measurements down-mail: schade@bessy.de, Telephone: +49 30 6392-3449, www.iris.bessy.de #12;Figure 1. Measured far-IR intensity

  6. Spherically symmetric cosmological spacetimes with dust and radiation — numerical implementation

    SciTech Connect (OSTI)

    Lim, Woei Chet [Department of Mathematics, University of Waikato, Private Bag 3105, Hamilton 3240 (New Zealand); Regis, Marco [Dipartimento di Fisica, Università di Torino and INFN, Torino (Italy); Clarkson, Chris, E-mail: wclim@waikato.ac.nz, E-mail: regis@to.infn.it, E-mail: chris.clarkson@gmail.com [Astrophysics, Cosmology and Gravity Centre, and Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, Cape Town (South Africa)

    2013-10-01T23:59:59.000Z

    We present new numerical cosmological solutions of the Einstein Field Equations. The spacetime is spherically symmetric with a source of dust and radiation approximated as a perfect fluid. The dust and radiation are necessarily non-comoving due to the inhomogeneity of the spacetime. Such a model can be used to investigate non-linear general relativistic effects present during decoupling or big-bang nucleosynthesis, as well as for investigating void models of dark energy with isocurvature degrees of freedom. We describe the full evolution of the spacetime as well as the redshift and luminosity distance for a central observer. After demonstrating accuracy of the code, we consider a few example models, and demonstrate the sensitivity of the late time model to the degree of inhomogeneity of the initial radiation contrast.

  7. Observable dark radiation from cosmologically safe QCD axion

    E-Print Network [OSTI]

    Kawasaki, Masahiro; Yanagida, Tsutomu T

    2015-01-01T23:59:59.000Z

    We propose a QCD axion model that avoids the cosmological domain wall problem, introducing a global SU(3)_f family symmetry to which we embed the unwanted PQ discrete symmetry. The spontaneous breaking of SU(3)_f and PQ symmetry predicts eight NG bosons as well as axion, all of which contribute to dark radiation in the Universe. The derivation from the standard model prediction of dark radiation can be observed by future observations of CMB fluctuations. Our model also predicts a sizable exotic kaon decay rate, which is marginally consistent with the present collider data and would be tested by future collider experiments.

  8. Radiation physics, biophysics, and radiation biology. Progress report, December 1, 1992--November 30, 1993

    SciTech Connect (OSTI)

    Hall, E.J.; Zaider, M.

    1993-05-01T23:59:59.000Z

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood ``biological fingerprint`` of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  9. Radiation zeros in weak boson production processes at hadron colliders

    E-Print Network [OSTI]

    F. Mamedov

    2001-07-31T23:59:59.000Z

    The Standard Model amplitudes for processes where one or more gauge bosons are emitted exhibit zeros in the angular distributions. The theoretical and experimental aspects of these radiation amplitude zeros are reviewed and some recent results are discussed. In particular, the zeros of the $WZ\\gamma$ and $WZZ$ production amplitudes are analyzed. It is briefly explained how radiation zeros can be used to test the SM.

  10. On the origin of Gamma Ray Burst radiation

    E-Print Network [OSTI]

    G. Ghisellini

    2001-01-17T23:59:59.000Z

    In the standard internal shock model, the observed X and gamma-ray radiation is assumed to be produced by synchrotron emission. I will show that there are serious problems with this interpretation, calling for other radiation mechanisms, such as quasi-thermal Comptonization and/or Compton drag processes, or both. These new ideas can have important consequences on the more general internal shock scenario, and can be tested by future observations.

  11. Transition radiation in turbulent astrophysical medium. Application to solar radio bursts

    E-Print Network [OSTI]

    Gregory D. Fleishman; Dale E. Gary; Gelu M. Nita

    2007-10-01T23:59:59.000Z

    Modern observations and models of various astrophysical objects suggest that many of their physical parameters fluctuate substantially at different spatial scales. The rich variety of the emission processes, including Transition Radiation but not limited to it, arising in such turbulent media constitutes the scope of Stochastic Theory of Radiation. We review general approaches applied in the stochastic theory of radiation and specific methods used to calculate the transition radiation produced by fast particles in the magnetized randomly inhomogeneous plasma. The importance of the theory of transition radiation for astrophysics is illustrated by one example of its detailed application to a solar radio burst, including specially designed algorithms of the spectral forward fitting.

  12. Radiation imaging apparatus

    DOE Patents [OSTI]

    Anger, Hal O. (Berkeley, CA); Martin, Donn C. (Berkeley, CA); Lampton, Michael L. (Berkeley, CA)

    1983-01-01T23:59:59.000Z

    A radiation imaging system using a charge multiplier and a position sensitive anode in the form of periodically arranged sets of interconnected anode regions for detecting the position of the centroid of a charge cloud arriving thereat from the charge multiplier. Various forms of improved position sensitive anodes having single plane electrode connections are disclosed. Various analog and digital signal processing systems are disclosed, including systems which use the fast response of microchannel plates, anodes and preamps to perform scintillation pulse height analysis digitally.

  13. Radiation Field on Superspace

    E-Print Network [OSTI]

    P. F. Gonzalez-Diaz

    1994-03-18T23:59:59.000Z

    We study the dynamics of multiwormhole configurations within the framework of the Euclidean Polyakov approach to string theory, incorporating a modification to the Hamiltonian which makes it impossible to interpret the Coleman Alpha parameters of the effective interactions as a quantum field on superspace, reducible to an infinite tower of fields on space-time. We obtain a Planckian probability measure for the Alphas that allows $\\frac{1}{2}\\alpha^{2}$ to be interpreted as the energy of the quanta of a radiation field on superspace whose values may still fix the coupling constants.

  14. Solar radiation intensity calculations 

    E-Print Network [OSTI]

    Levine, Randolph Steven

    1978-01-01T23:59:59.000Z

    , radiation per unit area per unit time, on a flat-plate collector is given by: I = I cos B (2. 1a) where I is the solar constant. insolation received at one astro- nomical unit from the sun. Since clear sky conditions are assumed I o w i 1 1 b e a.... INSOLATION EQUATIONS TABLE OF CONTENTS Page III. RESULTS AND CONCLUSIONS REFERENCES APPENDIX VITA 25 47 48 52 Vi LIST OF TABLES TABLE I. Optimal Inclination for Ap=O, No Checks for Ip &0 and a Time Independent Solar Constant. II. Optimal...

  15. Radiative ?(1S) decays

    E-Print Network [OSTI]

    Baringer, Philip S.

    1990-03-01T23:59:59.000Z

    — wW~ ii~ ~ + v~ 1''&WV'' V 0.20 0.45 0.70 ~y ~ EBFA~ 0.95 l.20 FIG. 4. Energy spectrum (normalized to beam energy) for Y~y2(h+h ) event candidates, with continuum data and ex- pected background from Y~m 2(h +h ) overplotted. 40 30— ~ 20— LLI IO— hl...PHYSICAL REVIEW 0 VOLUME 41, NUMBER 5 Radiative T(lS) decays 1 MARCH 1990 R. Fulton, M. Hempstead, T. Jensen, D. R. Johnson, H. Kagan, R. Kass, F. Morrow, and J. Whitmore Ohio State University, Columbus, Ohio 43210 W.-Y. Chen, J. Dominick, R. L. Mc...

  16. Radiation imaging apparatus

    DOE Patents [OSTI]

    Anger, H.O.; Martin, D.C.; Lampton, M.L.

    1983-07-26T23:59:59.000Z

    A radiation imaging system using a charge multiplier and a position sensitive anode in the form of periodically arranged sets of interconnected anode regions for detecting the position of the centroid of a charge cloud arriving thereat from the charge multiplier. Various forms of improved position sensitive anodes having single plane electrode connections are disclosed. Various analog and digital signal processing systems are disclosed, including systems which use the fast response of microchannel plates, anodes and preamps to perform scintillation pulse height analysis digitally. 15 figs.

  17. Radiation Emergency Procedure Demonstrations

    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: National5Sales for4,645U.S. DOE Office of Science (SC)IntegratedSpeedingTechnicalPurchase, Delivery, andSmartRadiation Effects

  18. Radiation Safety Test

    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: National5Sales for4,645U.S. DOE Office of Science (SC)IntegratedSpeedingTechnicalPurchase, Delivery, andSmartRadiation

  19. Radiation Control Program and Radiation Control Act (Nebraska)

    Broader source: Energy.gov [DOE]

    This statute authorizes the state to implement a regulatory program for sources of radiation, and contains rules for the Department, licensing and registration, and taxation of radioactive materials.

  20. Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture

    SciTech Connect (OSTI)

    Scott Wilde, Raymond Keegan

    2008-07-01T23:59:59.000Z

    The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

  1. Performance modeling of an integral, self-regulating cesium reservoir for the ATI-TFE

    SciTech Connect (OSTI)

    Thayer, K.L.; Ramalingam, M.L. (UES, In., 4401 Dayton-Xenia Road, Dayton, Ohio 45432-1894 (United States)); Young, T.J. (Aerospace Power Division, Wright Laboratory/POOC, Wright-Patterson AFB, Ohio 45433-6563 (United States))

    1993-01-20T23:59:59.000Z

    This work covers the performance modeling of an integral metal-matrix cesium-graphite reservoir for operation in the Advanced Thermionic Initiative-Thermionic Fuel Element (ATI-TFE) converter configuration. The objectives of this task were to incorporate an intercalated cesium-graphite reservoir for the 3C[sub 24]Cs[r arrow]2C[sub 36]Cs+Cs[sub (g)] two phase equilibrium reaction into the emitter lead region of the ATI-TFE. A semi two-dimensional, cylindrical TFE computer model was used to obtain thermal and electrical converter output characteristics for various reservoir locations. The results of this study are distributions for the interelectrode voltage, output current density, and output power density as a function of axial position along the TFE emitter. This analysis was accomplished by identifying an optimum cesium pressure for three representative pins in the ATI driverless'' reactor core and determining the corresponding position of the graphite reservoir in the ATI-TFE lead region. The position for placement of the graphite reservoir was determined by performing a first-order heat transfer analysis of the TFE lead region to determine its temperature distribution. The results of this analysis indicate that for the graphite reservoirs investigated the 3C[sub 24]Cs[r arrow]2C[sub 36]Cs+Cs[sub (g)] equilibrium reaction reservoir is ideal for placement in the TFE emitter lead region. This reservoir can be directly coupled to the emitter, through conduction, to provide the desired cesium pressure for optimum performance. The cesium pressure corresponding to the optimum converter output performance was found to be 2.18 torr for the ATI core least power TFE, 2.92 torr for the average power TFE, and 4.93 torr for the maximum power TFE.

  2. Investigation of spectral radiation heat transfer and NO{sub x} emission in a glass furnace

    SciTech Connect (OSTI)

    Golchert, B.; Zhou, C. Q.; Chang, S. L.; Petrick, M.

    2000-08-02T23:59:59.000Z

    A comprehensive radiation heat transfer model and a reduced NOx kinetics model were coupled with a computational fluid dynamics (CFD) code and then used to investigate the radiation heat transfer, pollutant formation and flow characteristics in a glass furnace. The radiation model solves the spectral radiative transport equation in the combustion space of emitting and absorbing media, i.e., CO{sub 2}, H{sub 2}O, and soot and emission/reflection from the furnace crown. The advanced numerical scheme for calculating the radiation heat transfer is extremely effective in conserving energy between radiation emission and absorption. A parametric study was conducted to investigate the impact of operating conditions on the furnace performance with emphasis on the investigation into the formation of NOx.

  3. NINTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect (OSTI)

    Daugherty, W.

    2014-08-06T23:59:59.000Z

    A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. One approach has been to periodically evaluate the leak performance of O-rings being aged in mock-up 9975 Primary Containment Vessels (PCVs) at elevated temperatures. Other methods such as compression-stress relaxation (CSR) tests and field surveillance are also on-going to evaluate O-ring behavior. Seventy tests using PCV mock-ups were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they continue to meet the leak-tightness criterion defined in ANSI standard N14.5-97. Due to material substitution, fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. High temperature aging continues for 23 GLT O-ring fixtures at 200 – 270 ºF. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The earliest 300 °F GLT O-ring fixture failure was observed at 34 months. The remaining GLT O-ring fixtures aging at 300 ºF have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 72 - 96 months, which bounds O-ring temperatures anticipated during storage in K-Area Complex (KAC). Based on expectations that the 200 ºF fixtures will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging in 2011 at 270 ºF, with hopes that they may reach a failure condition before the 200 ºF fixtures, thus providing additional time to failure data. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 – 300 ºF. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 ºF. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 ºF for 54 - 57 months. No additional O-ring failures have been observed since the last interim report was issued. Aging and periodic leak testing will continue for the remaining PCV fixtures. Additional irradiation of several fixtures is recommended to maintain a balance between thermal and radiation exposures similar to that experienced in storage, and to show the degree of consistency of radiation response between GLT and GLT-S O-rings.

  4. RADIATIVE RAYLEIGH-TAYLOR INSTABILITIES

    SciTech Connect (OSTI)

    Jacquet, Emmanuel [Laboratoire de Mineralogie et Cosmochimie de Museum (LMCM), CNRS and Museum National d'Histoire Naturelle, UMR 7202, 57 rue Cuvier, 75005 Paris (France); Krumholz, Mark R., E-mail: ejacquet@mnhn.fr, E-mail: krumholz@ucolick.org [Department of Astronomy, University of California, Santa Cruz, CA 95064 (United States)

    2011-04-01T23:59:59.000Z

    We perform analytic linear stability analyses of an interface separating two stratified media threaded by a radiation flux, a configuration relevant in several astrophysical contexts. We develop a general framework for analyzing such systems and obtain exact stability conditions in several limiting cases. In the optically thin, isothermal regime, where the discontinuity is chemical in nature (e.g., at the boundary of a radiation pressure-driven H II region), radiation acts as part of an effective gravitational field, and instability arises if the effective gravity per unit volume toward the interface overcomes that away from it. In the optically thick 'adiabatic' regime where the total (gas plus radiation) specific entropy of a Lagrangian fluid element is conserved, for example at the edge of radiation pressure-driven bubble around a young massive star, we show that radiation acts like a modified equation of state and derive a generalized version of the classical Rayleigh-Taylor stability condition.

  5. Radiator Labs | Department of Energy

    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's PossibleRadiation Protection Radiation Protection Regulations: TheCompetition » Radiator Labs

  6. Radiation Embrittlement Archive Project

    SciTech Connect (OSTI)

    Klasky, Hilda B [ORNL] [ORNL; Bass, Bennett Richard [ORNL] [ORNL; Williams, Paul T [ORNL] [ORNL; Phillips, Rick [ORNL] [ORNL; Erickson, Marjorie A [ORNL] [ORNL; Kirk, Mark T [ORNL] [ORNL; Stevens, Gary L [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    The Radiation Embrittlement Archive Project (REAP), which is being conducted by the Probabilistic Integrity Safety Assessment (PISA) Program at Oak Ridge National Laboratory under funding from the U.S. Nuclear Regulatory Commission s (NRC) Office of Nuclear Regulatory Research, aims to provide an archival source of information about the effect of neutron radiation on the properties of reactor pressure vessel (RPV) steels. Specifically, this project is an effort to create an Internet-accessible RPV steel embrittlement database. The project s website, https://reap.ornl.gov, provides information in two forms: (1) a document archive with surveillance capsule(s) reports and related technical reports, in PDF format, for the 104 commercial nuclear power plants (NPPs) in the United States, with similar reports from other countries; and (2) a relational database archive with detailed information extracted from the reports. The REAP project focuses on data collected from surveillance capsule programs for light-water moderated, nuclear power reactor vessels operated in the United States, including data on Charpy V-notch energy testing results, tensile properties, composition, exposure temperatures, neutron flux (rate of irradiation damage), and fluence, (Fast Neutron Fluence a cumulative measure of irradiation for E>1 MeV). Additionally, REAP contains data from surveillance programs conducted in other countries. REAP is presently being extended to focus on embrittlement data analysis, as well. This paper summarizes the current status of the REAP database and highlights opportunities to access the data and to participate in the project.

  7. EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMAN POPULATIONS FOLLOWING ACUTE EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION

    E-Print Network [OSTI]

    Fabrikant, J.I.

    2010-01-01T23:59:59.000Z

    EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION . Jacobexposed to nuclear explosions and medical radiation. Sinceto nuclear explo ions or medical radiation, describes the

  8. Radiation Safety Work Control Form

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

    Radiation Safety Work Control Form (see instructions on pg-3) Rev. May 2014 Area: Form : Date: Preliminary Applicability Screen: (a) Will closing the beam line injection stoppers...

  9. Inverse problem for Bremsstrahlung radiation

    SciTech Connect (OSTI)

    Voss, K.E.; Fisch, N.J.

    1991-10-01T23:59:59.000Z

    For certain predominantly one-dimensional distribution functions, an analytic inversion has been found which yields the velocity distribution of superthermal electrons given their Bremsstrahlung radiation. 5 refs.

  10. Enhanced radiation resistant fiber optics

    DOE Patents [OSTI]

    Lyons, P.B.; Looney, L.D.

    1993-11-30T23:59:59.000Z

    A process for producing an optical fiber having enhanced radiation resistance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation. 4 figures.

  11. Radiating Levi-Civita Spacetime

    E-Print Network [OSTI]

    Ozgur Delice

    2005-06-06T23:59:59.000Z

    This paper has been withdrawn by the author, See J.Krishna Rao, J. Phys. A: Gen. Phys., 4, 17 (1971) for radiating Levi-Civita metric.

  12. Scintillator Waveguide For Sensing Radiation

    DOE Patents [OSTI]

    Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder; Paul L. (Richland, WA)

    2003-04-22T23:59:59.000Z

    The present invention is an apparatus for detecting ionizing radiation, having: a waveguide having a first end and a second end, the waveguide formed of a scintillator material wherein the therapeutic ionizing radiation isotropically generates scintillation light signals within the waveguide. This apparatus provides a measure of radiation dose. The apparatus may be modified to permit making a measure of location of radiation dose. Specifically, the scintillation material is segmented into a plurality of segments; and a connecting cable for each of the plurality of segments is used for conducting scintillation signals to a scintillation detector.

  13. Enhanced radiation resistant fiber optics

    DOE Patents [OSTI]

    Lyons, Peter B. (Los Alamos, NM); Looney, Larry D. (Los Alamos, NM)

    1993-01-01T23:59:59.000Z

    A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.

  14. Quality Services: Radiation (New York)

    Broader source: Energy.gov [DOE]

    These regulations establish standards for protection against ionizing radiation resulting from the disposal and discharge of radioactive material to the environment. The regulations apply to any...

  15. Radiation Effects in the Space Telecommunications Environment

    SciTech Connect (OSTI)

    Fleetwood, Daniel M.; Winokur, Peter S.

    1999-05-17T23:59:59.000Z

    Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a telecommmiications system with significant space assets. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event. Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging. Prospects are discussed for device modeling and for the use of standard commercial electronics in space.

  16. ON THE KINETIC ENERGY AND RADIATIVE EFFICIENCY OF GAMMA-RAY BURSTS Nicole M. Lloyd-Ronning1

    E-Print Network [OSTI]

    Zhang, Bing

    ON THE KINETIC ENERGY AND RADIATIVE EFFICIENCY OF GAMMA-RAY BURSTS Nicole M. Lloyd-Ronning1 of 17 gamma-ray bursts (GRBs) during the afterglow phase and ac- counting for radiative losses, we the implications of these results for the GRB radiation and jet models. Subject headinggs: gamma rays: bursts

  17. Prediction of Solar Radiation on Building Rooftops: A Data-Mining Approach

    SciTech Connect (OSTI)

    Omitaomu, Olufemi A [ORNL; Bhaduri, Budhendra L [ORNL; Kodysh, Jeffrey B [ORNL

    2012-01-01T23:59:59.000Z

    Solar energy technologies offer a clean, renewable, and domestic energy source, and are essential components of a sustainable energy future. The accurate measurement of solar radiation data is essential for optimum site selection of future distributed solar power plants as well as sizing photovoltaic systems. However, solar radiation data are not readily available because measured sequences of radiation values are obtained for a few locations in a country. When the data are available, they are usually at different time periods and spatial scale. The availability of solar radiation data at hourly or daily time scale will enhance the integration of solar energy into electricity generation and promote a sustainable energy future. The ability to generate approximate solar radiation values is often the only practical way to obtain radiation data at hourly or daily time scale. As a result, several models have been developed for estimating solar radiation values based on analytical, numerical simulation, and statistical approaches. However, these models have inherent challenges. We will discuss some of those challenges in this paper. To enhance the prediction of solar radiation values, a novel approach is presented for estimating solar radiation values using support vector machine technique. The approach accounts for unique characteristics that influence solar radiation values. The preliminary results obtained offer useful insights for model enhancements.

  18. Atmospheric Radiation Measurement Climate Research Facility (ACRF) Annual Report 2008

    SciTech Connect (OSTI)

    LR Roeder

    2008-12-01T23:59:59.000Z

    The Importance of Clouds and Radiation for Climate Change: The Earth’s surface temperature is determined by the balance between incoming solar radiation and thermal (or infrared) radiation emitted by the Earth back to space. Changes in atmospheric composition, including greenhouse gases, clouds, and aerosols, can alter this balance and produce significant climate change. Global climate models (GCMs) are the primary tool for quantifying future climate change; however, there remain significant uncertainties in the GCM treatment of clouds, aerosol, and their effects on the Earth’s energy balance. In 1989, the U.S. Department of Energy (DOE) Office of Science created the Atmospheric Radiation Measurement (ARM) Program to address scientific uncertainties related to global climate change, with a specific focus on the crucial role of clouds and their influence on the transfer of radiation in the atmosphere. To reduce these scientific uncertainties, the ARM Program uses a unique twopronged approach: • The ARM Climate Research Facility, a scientific user facility for obtaining long-term measurements of radiative fluxes, cloud and aerosol properties, and related atmospheric characteristics in diverse climate regimes; and • The ARM Science Program, focused on the analysis of ACRF and other data to address climate science issues associated with clouds, aerosols, and radiation, and to improve GCMs. This report provides an overview of each of these components and a sample of achievements for each in fiscal year (FY) 2008.

  19. Atmospheric Radiation Measurement Program Science Plan

    SciTech Connect (OSTI)

    Ackerman, T

    2004-10-31T23:59:59.000Z

    The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: Maintain the data record at the fixed ARM sites for at least the next five years. Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. Implement and evaluate an operational methodology to calculate broad-band heating rates in the atmospheric columns at the ARM sites. Develop and implement methodologies to use ARM data more effectively to test atmospheric models, both at the cloud-resolving model scale and the GCM scale. Use these methodologies to diagnose cloud parameterization performance and then refine these parameterizations to improve the accuracy of climate model simulations. In addition, the ARM Program is actively developing a new ARM Mobile Facility (AMF) that will be available for short deployments (several months to a year or more) in climatically important regions. The AMF will have much of the same instrumentation as the remote facilities at ARM's Tropical Western Pacific and the North Slope of Alaska sites. Over time, this new facility will extend ARM science to a much broader range of conditions for model testing.

  20. Influence of clouds and diffuse radiation on ecosystem-atmosphere CO 2 and CO 18 O exchanges

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    surface model with BOREAS aspen and jack pine tower fluxes,to diffuse radiation by an aspen-dominated northern hardwood