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We encourage you to perform a real-time search of NLEBeta
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1

Measured Radiation and Background Levels During Transmission of Megawatt Electron Beams Through Millimeter Apertures  

SciTech Connect (OSTI)

We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-off, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW continuous-wave (CW) beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, multipactoring inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation when the machine is tuned for 130 MeV operation.

Alarcon, Ricardo [Arizona State University, Glendale, AZ (United States); Balascuta, S. [Arizona State University, Glendale, AZ (United States); Benson, Stephen V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Bertozzi, William [Massachusetts Institute of Technology, Cambridge, MA (United States); Boyce, James R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Cowan, Ray [Massachusetts Institute of Technology, Cambridge, MA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Evtushenko, Pavel [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Fisher, P. [Massachusetts Institute of Technology, Cambridge, MA (United States); Ihloff, Ernest E. [Hampton University, Hampton, VA (United States); Kalantarians, Narbe [Hampton University, Hampton, VA (United States); Kelleher, Aidan Michael [Massachusetts Institute of Technology, Cambridge, MA (United States); Krossler, W. J. [William and Mary College, Williamsburg, VA (United States); Legg, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Long, Elena [University of New Hampshire, Durham, NH (United States); Milner, Richard [Massachusetts Institute of Technology, Cambridge, MA (United States); Neil, George R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Ou, Longwu [Massachusetts Institute of Technology, Cambridge, MA (United States); Schmookler, Barack Abraham [Massachusetts Institute of Technology, Cambridge, MA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Tschalar, C. [Massachusetts Institute of Technology, Cambridge, MA (United States); Williams, Gwyn P. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, Shukui [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2013-11-01T23:59:59.000Z

2

State background-radiation levels: results of measurements taken during 1975-1979  

SciTech Connect (OSTI)

Background radiation levels across the United States have been measured by the Off-Site Pollutant Measurements Group of the Health and Safety Research Division at Oak Ridge National Laboratory (ORNL). These measurements have been conducted as part of the ORNL program of radiological surveillance at inactive uranium mills and sites formerly utilized during Manhattan Engineer District and early Atomic Energy Commission projects. The measurements included determination of /sup 226/Ra, /sup 232/Th, and /sup 238/U concentrations in surface soil samples and measurement of external gamma-ray exposure rates at 1 m above the ground surface at the location of soil sampling. This information is being utilized for comparative purposes to determine the extent of contamination present at the survey sites and surrounding off-site areas. The sampling program to date has provided background information at 356 locations in 33 states. External gamma-ray exposure rates were found to range from less than 1 to 34 ..mu..R/h, with an US average of 8.5 ..mu..R/h. The nationwide average concentrations of /sup 226/Ra, /sup 232/Th, and /sup 238/U in surface soil were determined to be 1.1, 0.98, and 1.0 pCi/g, respectively.

Myrick, T.E.; Berven, B.A.; Haywood, F.F.

1981-11-01T23:59:59.000Z

3

Local microwave background radiation  

E-Print Network [OSTI]

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.

Domingos Soares

2014-11-13T23:59:59.000Z

4

Radiation and Background Levels in a CLIC Detector due to Beam-Beam Effects Optimisation of Detector Geometries and Technologies  

E-Print Network [OSTI]

The high charge density---due to small beam sizes---and the high energy of the proposed CLIC concept for a linear electron--positron collider with a centre-of-mass energy of up to 3~TeV lead to the production of a large number of particles through beam-beam interactions at the interaction point during every bunch crossing (BX). A large fraction of these particles safely leaves the detector. A still significant amount of energy will be deposited in the forward region nonetheless, which will produce secondary particles able to cause background in the detector. Furthermore, some particles will be created with large polar angles and directly cause background in the tracking detectors and calorimeters. The main sources of background in the detector, either directly or indirectly, are the incoherent $mathrm{e}^{+}mathrm{e}^{-}$ pairs and the particles from $gammagamma ightarrow$ hadron events. The background and radiation levels in the detector have to be estimated, to study if a detector is feasible, that can han...

Sailer, André; Lohse, Thomas

2013-01-10T23:59:59.000Z

5

The Cosmic Background Radiation  

E-Print Network [OSTI]

We summarise the current status of cosmic microwave background spectrum and anisotropy measurements, and their theoretical interpretation. This is the update of the mini-review for the 1997 web-version of the Review of Particle Properties.

George Smoot; Douglas Scott

1997-11-08T23:59:59.000Z

6

DarkLight radiation backgrounds  

SciTech Connect (OSTI)

We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-on, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW CW beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, field emission inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation.

Kalantarians, N. [Department of Physics, Hampton University, Hampton VA 23668 (United States); Collaboration: DarkLight Collaboration

2013-11-07T23:59:59.000Z

7

An electronic radiation of blackbody: Cosmic electron background  

E-Print Network [OSTI]

The Universe owns the electronic radiation of blackbody at temperature 2.725 K, which we call the cosmic electron background. We calculate its radiation spectrum. The energy distribution of number density of electrons in the cosmic electron background becomes zero as energy goes to both zero and infinity. It has one maximum peak near the energy level of 10**(-23) J.

Jian-Miin Liu

2008-02-23T23:59:59.000Z

8

Cosmic Background Radiation Due to Photon Condensation  

E-Print Network [OSTI]

It is shown that a collection of photons with nearly the same frequency exhibits a Bose "condensation" type of phenomenon at about 3 degrees K corresponding to a peak intensity at a wave length of about 0.4cm. This could give a mechanism for the observed Cosmic Background Radiation, and also explain some curious features.

B. G. Sidharth

1998-06-10T23:59:59.000Z

9

apm background radiation: Topics by E-print Network  

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

Extragalactic Background Radiation Astrophysics (arXiv) Summary: Attenuation of high--energy gamma rays by pair--production with UV, optical and IR background photons provides a...

10

POLARIZATION OF THE COSMIC BACKGROUND RADIATION  

E-Print Network [OSTI]

a 45° angle. Radiation whose electric field (polarization)radiation field, it can be uniquely characterized by its electric

Lubin, Philip Lubin

2010-01-01T23:59:59.000Z

11

ESnet supports Sandia and APNIC IPv6 Background Radiation research  

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

supports Sandia and APNIC IPv6 Background Radiation research Engineering Services The Network OSCARS Fasterdata IPv6 Network IPv6 Implementation Checklist ESnet IPv6 Mirror Servers...

12

Tree level Leptogenesis from Kalb-Ramond Torsion Background  

E-Print Network [OSTI]

The effect of torsion in theories of quantum gravity is known to be well described by an axion-like field which couples to matter as well as to gravitation and radiation gauge fields. In this note we consider a particular kind of torsion, arising from the Kalb-Ramond antisymmetric tensor field that appears in the gravitational multiplet of string theory. We investigate the implications for leptogenesis. It is shown that leptogenesis can occur even at tree-level and with only one generation of right-handed Majorana neutrinos, due to CP and CPT violation introduced by the background geometry.

M. de Cesare; Nick E. Mavromatos; Sarben Sarkar

2015-02-03T23:59:59.000Z

13

THE HIGH BACKGROUND RADIATION AREA IN RAMSAR IRAN: GEOLOGY, NORM, BIOLOGY, LNT, AND POSSIBLE REGULATORY FUN  

SciTech Connect (OSTI)

The city of Ramsar Iran hosts some of the highest natural radiation levels on earth, and over 2000 people are exposed to radiation doses ranging from 1 to 26 rem per year. Curiously, inhabitants of this region seem to have no greater incidence of cancer than those in neighboring areas of normal background radiation levels, and preliminary studies suggest their blood cells experience fewer induced chromosomal abnormalities when exposed to 150 rem ''challenge'' doses of radiation than do the blood cells of their neighbors. This paper will briefly describe the unique geology that gives Ramsar its extraordinarily high background radiation levels. It will then summarize the studies performed to date and will conclude by suggesting ways to incorporate these findings (if they are borne out by further testing) into future radiation protection standards.

Karam, P. A.

2002-02-25T23:59:59.000Z

14

Integrated Molecular Analysis Indicates Undetectable Change in DNA Damage in Mice after Continuous Irradiation at ~ 400-fold Natural Background Radiation  

E-Print Network [OSTI]

Background: In the event of a nuclear accident, people are exposed to elevated levels of continuous low dose-rate radiation. Nevertheless, most of the literature describes the biological effects of acute radiation.

Olipitz, Werner

15

Low Background Radiation Experiment Yields Interesting Preliminary Results  

Broader source: Energy.gov [DOE]

CARLSBAD, N.M., May 18, 2011 – New Mexico State University?s Low Background Radiation Experiment (LBRE), which takes place 2,150 feet below the earth?s surface at the Waste Isolation Pilot Plant, recently released some results about the project?s first two years of experimentation.

16

Position sensitive detection of neutrons in high radiation background field  

SciTech Connect (OSTI)

We present the development of a high-resolution position sensitive device for detection of slow neutrons in the environment of extremely high ? and e{sup ?} radiation background. We make use of a planar silicon pixelated (pixel size: 55 × 55 ?m{sup 2}) spectroscopic Timepix detector adapted for neutron detection utilizing very thin {sup 10}B converter placed onto detector surface. We demonstrate that electromagnetic radiation background can be discriminated from the neutron signal utilizing the fact that each particle type produces characteristic ionization tracks in the pixelated detector. Particular tracks can be distinguished by their 2D shape (in the detector plane) and spectroscopic response using single event analysis. A Cd sheet served as thermal neutron stopper as well as intensive source of gamma rays and energetic electrons. Highly efficient discrimination was successful even at very low neutron to electromagnetic background ratio about 10{sup ?4}.

Vavrik, D., E-mail: vavrik@itam.cas.cz [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, Prague (Czech Republic); Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecka 76, 190 00 Prague 9 (Czech Republic); Jakubek, J.; Pospisil, S. [Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecka 76, 190 00 Prague 9 (Czech Republic)] [Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecka 76, 190 00 Prague 9 (Czech Republic); Vacik, J. [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Rez, 250 68 Prague, Czech Republic (Czech Republic)] [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Rez, 250 68 Prague, Czech Republic (Czech Republic)

2014-01-15T23:59:59.000Z

17

Radiative emission of neutrino pair free of quantum electrodynamic backgrounds  

E-Print Network [OSTI]

A scheme of quantum electrodynamic (QED) background-free radiative emission of neutrino pair (RENP) is proposed in order to achieve precision determination of neutrino properties so far not accessible. The important point for the background rejection is the fact that the dispersion relation between wave vector along propagating direction in wave guide (and in a photonic-crystal type fiber) and frequency is modified by a discretized non-vanishing effective mass. This effective mass acts as a cutoff of allowed frequencies, and one may select the RENP photon energy region free of all macro-coherently amplified QED processes by choosing the cutoff larger than the mass of neutrinos.

M. Yoshimura; N. Sasao; M. Tanaka

2015-01-23T23:59:59.000Z

18

Radiative emission of neutrino pair free of quantum electrodynamic backgrounds  

E-Print Network [OSTI]

A scheme of quantum electrodynamic (QED) background-free radiative emission of neutrino pair (RENP) is proposed in order to achieve precision determination of neutrino properties so far not accessible. The important point for the background rejection is the fact that the dispersion relation between wave vector along propagating direction in wave guide (and in a photonic-crystal type fiber) and frequency is modified by a discretized non-vanishing effective mass. This effective mass acts as a cutoff of allowed frequencies, and one may select the RENP photon energy region free of all macro-coherently amplified QED processes by choosing the cutoff larger than the mass of neutrinos.

Yoshimura, M; Tanaka, M

2015-01-01T23:59:59.000Z

19

Radiation shielding for underground low-background experiments  

E-Print Network [OSTI]

The design task of creating an efficient radiation shield for the new COBRA double-beta decay experiment led to a comprehensive study of commercially available shielding materials. The aim was to find the most efficient combination of materials under the constraints of an extreme low-background experiment operating in a typical underground laboratory. All existing shield configurations for this type of experiment have been found to perform sub-optimally in comparison to the class of multilayered configurations proposed in this study. The method used here to create a specific shield configuration should yield a close to optimal result when applied to any experiment utilising a radiation shield. In particular, the survey of single material response to a given radiation source turns out to give a guideline for the construction of efficient multilayer shields.

D. Y Stewart; P. F. Harrison; B. Morgan; Y. A. Ramachers

2006-07-31T23:59:59.000Z

20

Electromagnetic radiation in a time-varying background medium  

E-Print Network [OSTI]

Analytical solutions are presented for the electromagnetic radiation by an arbitrary pulsed source into a homogeneous time-varying background medium. In the constant-impedance case an explicit radiation formula is obtained for the synchronous permittivity and permeability described by any positive function of time. As might be expected, such a medium introduces significant spectral shifts and spatio-temporal modulation, which are analized here for the linear and exponential time-variations of the medium parameters. In the varying-impedance case the solution is obtained for the fourth-order polynomial time-dependence of the permittivity. In addition to the spectral shifts and modulation this spatially homogeneous medium scatters the field introducing causal echoes at the receiver location.

Budko, Neil V

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Large-Angular-Scale Anisotropy in the Cosmic Background Radiation  

DOE R&D Accomplishments [OSTI]

We report the results of an extended series of airborne measurements of large-angular-scale anisotropy in the 3 K cosmic background radiation. Observations were carried out with a dual-antenna microwave radiometer operating at 33 GHz (.089 cm wavelength) flown on board a U-2 aircraft to 20 km altitude. In eleven flights, between December 1976 and May 1978, the radiometer measured differential intensity between pairs of directions distributed over most of the northern hemisphere with an rms sensitivity of 47 mK Hz{sup 1?}. The measurements how clear evidence of anisotropy that is readily interpreted as due to the solar motion relative to the sources of the radiation. The anisotropy is well fit by a first order spherical harmonic of amplitude 360{+ or -}50km sec{sup -1} toward the direction 11.2{+ or -}0.5 hours of right ascension and 19 {+ or -}8 degrees declination. A simultaneous fit to a combined hypotheses of dipole and quadrupole angular distributions places a 1 mK limit on the amplitude of most components of quadrupole anisotropy with 90% confidence. Additional analysis places a 0.5 mK limit on uncorrelated fluctuations (sky-roughness) in the 3 K background on an angular scale of the antenna beam width, about 7 degrees.

Gorenstein, M. V.; Smoot, G. F.

1980-05-00T23:59:59.000Z

22

Technical background document for draft soil screening level guidance  

SciTech Connect (OSTI)

The document provides technical details of the derivation of the September 30, 1993, draft Soil Screening Levels (SSLs) Guidance for Superfund (PB93-963508). The document is presented in two sections. Section I defines SSL and provides background information on the development of SSLs and their application and implementation at Superfund sites, including sampling schemes for measuring SSL attainment. It also provides draft SSLs developed for 30 chemicals. Section II provides the technical basis for the development of SSLs addressing direct ingestion of soil, inhalation of volatiles and fugitive dust, and the soil-to-ground-water exposure pathway, including the assumptions and theories used the their development.

Not Available

1994-03-01T23:59:59.000Z

23

PCB Radiation Mechanisms: Using Component-Level Measurements to  

E-Print Network [OSTI]

1 PCB Radiation Mechanisms: Using Component-Level Measurements to PCB Radiation Mechanisms: Using Component-Level Measurements to Determine System-Level Radiated EmissionsDetermine System-Level Radiated Radiation Directly from PCB StructuresRadiation Directly from PCB Structures Signal or component voltage

Stuart, Steven J.

24

Background  

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

Background Solar panels are designed as a photovoltaic module. The energy producing aspect of the photovoltaic module has two primary steps. The first is a semiconducting material...

25

HEALTH EFFECTS OF LOW-LEVEL IONIZING RADIATION  

E-Print Network [OSTI]

LO~Z-lEVEL IONIZIN(l RADIATION Jacob I . Fabti kant April ··OF LOW~LEVEL IONIZING RADIATION BEFORE THE SUBCOMMITTEE ONwill low~level ionizing radiation. restricted primarily to

Fabrikant, Jacob I.

2012-01-01T23:59:59.000Z

26

BACKGROUND  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusA t i o n dataWhatNationalBACKGROUND The safe

27

Thermal and non-thermal radiation of rotating polarizable particle moving in an equilibrium background of electromagnetic radiation  

E-Print Network [OSTI]

A theory of thermal and nonthermal radiation in a vacuum background of arbitrary temperature generated by relativistic polarizable particle with spin is proposed. When the particle rotates, radiation is produced by vacuum fluctuations even in the case of zero temperature of the system. In the ultrarelativistic case, the spectral-angular intensity of radiation is concentrated along the velocity of the particle. At finite temperatures of particle and vacuum, the particle temperature (in its rest frame) rather quickly acquires an equilibrium magnitude depending on the velocities of rotation and uniform motion and the background temperature. This equilibrium temperature determines the intensity of radiation. The dynamical slowing down takes a very long time until the kinetic energy of uniform motion and rotation is converted into radiation.

A. A. Kyasov; G. V Dedkov

2014-09-17T23:59:59.000Z

28

Experimental study of variations in background radiation and the effect on Nuclear Car Wash sensitivity  

SciTech Connect (OSTI)

Error rates in a cargo screening system such as the Nuclear Car Wash [1-7] depend on the standard deviation of the background radiation count rate. Because the Nuclear Car Wash is an active interrogation technique, the radiation signal for fissile material must be detected above a background count rate consisting of cosmic, ambient, and neutron-activated radiations. It was suggested previously [1,6] that the Corresponding negative repercussions for the sensitivity of the system were shown. Therefore, to assure the most accurate estimation of the variation, experiments have been performed to quantify components of the actual variance in the background count rate, including variations in generator power, irradiation time, and container contents. The background variance is determined by these experiments to be a factor of 2 smaller than values assumed in previous analyses, resulting in substantially improved projections of system performance for the Nuclear Car Wash.

Church, J; Slaughter, D; Norman, E; Asztalos, S; Biltoft, P

2007-02-07T23:59:59.000Z

29

The Relationship of Rhythmic and Melodic Perception with Background Music Distraction in College Level Students  

E-Print Network [OSTI]

This study investigated relationships among the ability to audiate musical stimuli, background music condition, familiarity, gender, general academic achievement, age, and frequency of use on the level of distraction caused ...

Dove, Michael Karl

2009-04-27T23:59:59.000Z

30

Kernel Level Energy-Efficient 3G Background Traffic Shaper for Android Smartphones  

E-Print Network [OSTI]

Kernel Level Energy-Efficient 3G Background Traffic Shaper for Android Smartphones Ekhiotz Jon energy-efficient, the lack of energy aware- ness on the software front is becoming all too apparent

31

Developing a Methodology for Characterizing the Effects of Building Materials’ Natural Radiation Background on a Radiation Portal Monitoring System  

E-Print Network [OSTI]

, weather, and time of day. 6 Gamma rays are electromagnetic radiation emitted by excited nuclei in order for them to reach the ground state after decaying. Once emitted, these particles mainly interact with matter in three ways: photoelectric effect... and measured density were then used to define the MCNP material card for concrete. Pulse height tallies were used to determine the total gamma ray count rate in each of the four gamma detectors in the RPM. 5 CHAPTER II BACKGROUND II.A. Radiation...

Fitzmaurice, Matthew Blake 1988-

2012-11-06T23:59:59.000Z

32

A Shallow Underground Laboratory for Low-Background Radiation Measurements and Materials Development  

SciTech Connect (OSTI)

Abstract: Pacific Northwest National Laboratory recently commissioned a new shallow underground laboratory, located at a depth of approximately 30 meters water-equivalent. This new addition to the small class of radiation measurement laboratories located at modest underground depths worldwide houses the latest generation of custom-made, high-efficiency, low-background gamma-ray spectrometers and gas proportional counters. This manuscript describes the unique capabilities present in the shallow underground laboratory; these include large-scale ultra-pure materials production and a suite of radiation detection systems. Reported data characterize the degree of background reduction achieved through a combination of underground location, graded shielding, and rejection of cosmic-ray events. We conclude by presenting measurement targets and future opportunities.

Aalseth, Craig E.; Bonicalzi, Ricco; Cantaloub, Michael G.; Day, Anthony R.; Erikson, Luke E.; Fast, James E.; Forrester, Joel B.; Fuller, Erin S.; Glasgow, Brian D.; Greenwood, Lawrence R.; Hoppe, Eric W.; Hossbach, Todd W.; Hyronimus, Brian J.; Keillor, Martin E.; Mace, Emily K.; McIntyre, Justin I.; Merriman, Jason H.; Myers, Allan W.; Overman, Cory T.; Overman, Nicole R.; Panisko, Mark E.; Seifert, Allen; Warren, Glen A.; Runkle, Robert C.

2012-11-08T23:59:59.000Z

33

Influence of Spinning Electric Fields on Natural Background Gamma-Radiation  

E-Print Network [OSTI]

This paper considers influence of spinning electric field on statistics of natural background gamma-radiation. The spinning electric field, shown as a virtual gyroscope, has quantum mechanics characteristics. Interaction of the virtual fermion-like gyroscope with bosons (gamma-quanta) results in lowering intensity of the gamma-radiation and altering Poisson distribution. The statistic of the observed phenomenon depends on the direction of rotation of the virtual gyroscope. The results are discussed in a shade of spin-spin interaction having regard to realizing thermodynamically profitable conditions. Similarity of observed reduction of gamma-radiation in spinning electric fields and that for mechanical rotation stresses a special role of rotation itself, disregarding the matter of its carrier.

Mark Krinker; Felix Kitaichik

2010-04-28T23:59:59.000Z

34

Automotive Component Measurements forAutomotive Component Measurements for Determining VehicleDetermining Vehicle--Level RadiatedLevel Radiated  

E-Print Network [OSTI]

1 Automotive Component Measurements forAutomotive Component Measurements for Determining VehicleDetermining Vehicle--Level RadiatedLevel Radiated Automotive Component Measurements forAutomotive Component automotiveWe need to characterize automotive components the way we characterize circuitcomponents the way we

Stuart, Steven J.

35

Radiation levels on empty cylinders containing heel material  

SciTech Connect (OSTI)

Empty UF{sub 6} cylinders containing heel material were found to emit radiation levels in excess of 200 mr/hr, the maximum amount stated in ORO-651. The radiation levels were as high as 335 mr/hr for thick wall (48X and 48Y) cylinders and 1050 mr/hr for thin wall (48G and 48H) cylinders. The high readings were found only on the bottom of the cylinders. These radiation levels exceeded the maximum levels established in DOT 49 CFR, Part 173.441 for shipment of cylinders. Holding periods of four weeks for thick-wall cylinders and ten weeks for thin-wall cylinders were established to allow the radiation levels to decay prior to shipment.

Shockley, C.W. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31T23:59:59.000Z

36

Estimating GroundEstimating Ground--Level Solar RadiationLevel Solar Radiation and Evapotranspiration In Puerto Ricoand Evapotranspiration In Puerto Rico  

E-Print Network [OSTI]

Estimating GroundEstimating Ground--Level Solar RadiationLevel Solar Radiation radiation, therefore, solar radiation measurements throughout the island are essential. #12;Currently, including solar radiation ·In PR, solar radiation is only available at selected locations. · The majority

Gilbes, Fernando

37

Massive charged scalar field in the Kerr-Newman background II: Hawking radiation  

E-Print Network [OSTI]

We perform accurate calculations of the energy-, momentum-, and charge-emission rates of a charged scalar field in the background of the Kerr-Newman black hole at the range of parameters for which the effect is not negligibly small and, at the same time, the semiclassical regime is, at least marginally, valid. For black holes with charge below or not much higher than the charge accretion limit $Q \\sim \\mu M/e$ (where $e$ and $\\mu$ are the electron's mass and charge), the time between the consequent emitting of two charged particles is very large. For primordial black holes the transition between the increasing and decreasing of the ratio $Q/M$ occurs around the charge accretion limit. The rotation increases the intensity of radiation up to three orders, while the effect of the field's mass strongly suppresses the radiation.

R. A. Konoplya; A. Zhidenko

2014-04-03T23:59:59.000Z

38

Operating Experience Level 3, DOE Occupational Radiation Exposures for 2013  

Broader source: Energy.gov [DOE]

This Operating Experience Level 3 (OE-3) document provides an overview summary of radiation doses from occupational exposures at the Department of Energy (DOE), including the National Nuclear Security Administration for the year 2013.

39

Apparatus having reduced background for measuring radiation activity in aerosol particles  

DOE Patents [OSTI]

Apparatus having reduced background for measuring radiation activity in aerosol particles. A continuous air monitoring sampler is described for use in detecting the presence of alpha-emitting aerosol particles. An inlet fractionating screen has been demonstrated to remove about 95% of freshly formed radon progeny from the aerosol sample, and approximately 33% of partially aged progeny. Addition of an electrical condenser and a modified dichotomous virtual impactor are expected to produce considerable improvement in these numbers, the goal being to enrich the transuranic (TRU) fraction of the aerosols. This offers the possibility of improving the signal-to-noise ratio for the detected alpha-particle energy spectrum in the region of interest for detecting TRU materials associated with aerosols, thereby enhancing the performance of background-compensation algorithms for improving the quality of alarm signals intended to warn personnel of potentially harmful quantities of TRU materials in the ambient air.

Rodgers, John C. (Santa Fe, NM); McFarland, Andrew R. (College Station, TX); Oritz, Carlos A. (Bryan, TX); Marlow, William H. (College Station, TX)

1992-01-01T23:59:59.000Z

40

Network-level fallout radiation effects assessment. Final report  

SciTech Connect (OSTI)

National Security calls for the ability to maintain communication capabilities in times of national disaster, which could include a nuclear attack. Nuclear detonation has two basic by-products for which telecommunication equipments are susceptible to damage. These are electromagnetic pulse (EMP) and fallout radiation. The purposes of the EMP Mitigation Program are to analyze and to lessen the effects of EMP and fallout radiation on national telecommunications resources. Fallout radiation occurs after the initial intense high-frequency EMP, and is the subject of this analysis. Fallout radiation is the residual radiation that remains in the atmosphere after a nuclear blast, and which can be carried by weather conditions to locations far from the detonation point. This analysis focuses on the effects of fallout radiation on the telecommunications network of the American Telephone and Telegraph Co. (AT and T). This assessment of AT and T-network's communications-capabilities uses a network-level approach to assess fallout-radiation effects on the network's performance. The approach used was developed for assessing network-level EMP effects on Public Switched Network communication capabilities. Details are given on how EMP assessments utilize this method. Equipment-level fallout-radiation survivability data is also required.

Not Available

1991-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

SIMULATION OF RADIATION BACKGROUNDS ASSOCIATED WITH NUCLEAR DIAGNOSTICS IN THE NATIONAL IGNITION FACILITY  

SciTech Connect (OSTI)

Experiments resulting in a significant neutron yield are scheduled to start in 2010 at the National Ignition Facility (NIF). Several experiments utilizing Tritium-Hydrogen-Deuterium (THD) and Deuterium-Tritium (DT) targets are scheduled as part of the National Ignition Campaign (NIC). A wide range of diagnostics will be used to measure several parameters of implosion such as the core and fuel shape, temperatures and densities, and neutron yield. Accurate evaluations of the neutron and gamma backgrounds are important for several diagnostics, such as the High Energy X-ray Imager (HEXRI) and Neutron-Time-Of-Flight (nTOF). Several sources of neutron and gamma backgrounds will impact the accuracy of the diagnostics measurements. Fusion neutrons generated by fuel burn and secondary neutrons resulting from the fusion neutrons interaction with structures present inside and outside the Target Chamber (TC) contribute to the neutron background. In the meantime, X-rays emitted from the implosion, X-rays resulting from Laser Plasma Interaction (LPI) of NIF beams with the hohlraum, and gamma-rays induced by neutron interactions with different structures inside and outside the TC contribute to the gamma background. A detailed model has been developed of the NIF facility and all structures inside the TC. Several Monte-Carlo simulations were performed to identify the expected signal-to- background ratios at several potential locations for the HEXRI and nTOF diagnostics. Gamma backgrounds associated with HEXRI were significantly reduced by using a tungsten collimator. The collimator resulted in the reduction of the gamma background at the HEXRI scintillator by more than an order of magnitude during the first 40 ns following a THD shot. The nTOF20 detectors inside the Neutron Spectrometry room are exposed to low levels of neutron and gamma background during yield shots.

Khater, H; Dauffy, L; Tommasini, R; Eckart, M; Eder, D

2009-08-19T23:59:59.000Z

42

A New Upper Limit on the Polarization of the Cosmic Microwave Background Radiation  

E-Print Network [OSTI]

The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological parameters, such as the curvature of the universe, the shape of the spectrum of primordial density fluctuations, and the contribution of baryons, dark matter, and dark energy to the overall energy density of the universe. In addition to being spatially non-uniform, the CMB is theorized to be slightly polarized. Measurements of this polarization, particularly at large angular scales, have the potential to provide information on primordial gravitational waves, theories of inflation, and the ionization history of the universe, as well as help further constrain cosmological parameters. Polarization has not yet been detected in the CMB. This thesis describes a recent search for CMB polarization at large angular scales, conducted in the spring of 2000 at the University of Wisconsin-Madison. After a general introduction on both CMB polarization and general microwave polarimetry, details of the experiment itself are given, as well as a full description of the data selection and analysis techniques. Using these techniques, our data lead to a new upper limit on CMB polarization at large angular scales of 10 $\\mu$K in both E- and B-type polarization at 95% confidence. If B-polarization is assumed to be zero, the limit for E-type polarization is lowered to 8 $\\mu$K. This experiment is the first of a new breed of highly-sensitive instruments that will one day map out this interesting property of the Cosmic Microwave Background Radiation.

Christopher O'Dell

2002-01-15T23:59:59.000Z

43

Reduction of Radioactive Backgrounds in Electroformed Copper for Ultra-Sensitive Radiation Detectors  

SciTech Connect (OSTI)

Abstract Ultra-pure construction materials are required for the next generation of neutrino physics, dark matter and environmental science applications. These new efforts require materials with purity levels at or below 1 uBq/kg 232Th and 238U. Yet radiometric analysis lacks sensitivity below ~10 uBq/kg for the U and Th decay chains. This limits both the selection of clean materials and the validation of purification processes. Copper is an important high-purity material for low-background experiments due to the ease with which it can be purified by electrochemical methods. Electroplating for purification into near-final shapes, known as electroforming, is one such method. Continued refinement of the copper electroforming process is underway, for the first time guided by an ICP-MS based assay method that can measure 232Th and 238U near the desired purity levels. An assay of electroformed copper at 10 uBq/kg for 232Th has been achieved and is described. The implications of electroformed copper at or better than this purity on next-generation low-background experiments are discussed.

Hoppe, Eric W.; Aalseth, Craig E.; Farmer, Orville T.; Hossbach, Todd W.; Liezers, Martin; Miley, Harry S.; Overman, Nicole R.; Reeves, James H.

2014-02-08T23:59:59.000Z

44

Equipment level fallout radiation-effects approach. Final report  

SciTech Connect (OSTI)

National Security Decision Directive (NSDD) 97 and Executive Order (EO) 12472 call for the ability to maintain National Security Emergency Preparedness (NSEP) communication capabilities in times of national disaster, which includes a nuclear attack. The Office of the Manager, National Communications System (OMNCS) sponsors the Electromagnetic Pulse (EMP) Mitigation Program to evaluate and, where possible, mitigate the effects of the nuclear attack. Fallout radiation has been identified as an environment that may effect the performance of the regional and national telecommunication system. This report presents the investigations in the network-level fallout radiation methodology used to determine the effects of this environment. Alternative techniques are presented to improve the methodology.

Not Available

1989-02-10T23:59:59.000Z

45

Determining the Impact of Concrete Roadways on Gamma Ray Background Readings for Radiation Portal Monitoring Systems  

E-Print Network [OSTI]

country of origin. To combat the threat of nuclear trafficking, radiation portal monitors (RPMs) are deployed around the world to intercept illicit material while in transit by passively detecting gamma and neutron radiation. Portal monitors in some...

Ryan, Christopher Michael

2012-07-16T23:59:59.000Z

46

Are you sure that the anisotropies in the microwave background radiation are really cosmological rather than purely Galactic in origin?  

E-Print Network [OSTI]

New calculations of the Galactic contamination over microwave background radiation anisotropies are carried out. On one hand, when a frequency-dependent contrast of molecular clouds with respect to the Galactic background of the diffuse interstellar medium is taken into account, the anisotropic amplitude produced by Galactic dust is increased with respect to previous calculations and this is of the same order as that of the data from the observations. On the other hand, if we take into account rotational dust emission, for instance, a frequency independence of anisotropies in the microwave range may be obtained. This leads to the possibility that under some particular, but not impossible, conditions all the microwave background radiation anisotropies may be due to Galactic foregrounds rather than cosmological in origin. Moreover, a suspected coincidence between the typical angular sizes of the microwave background radiation anisotropies and those of nearby molecular clouds makes more plausible the hypothesis of a purely Galactic origin for these anisotropies. It is also argued that the correlation among structures at different frequencies, the comparison of the power spectrum at different frequencies and the galactic latitude dependence of the anisotropies are not yet proofs in favour of either a cosmological or Galactic origin.

M. Lopez-Corredoira

1999-05-01T23:59:59.000Z

47

Simulation of Radiation Backgrounds associated with the HEXRI Diagnostics at the National Ignition Facility  

SciTech Connect (OSTI)

Experiments resulting in a significant neutron yield are scheduled to start in 2010 at the National Ignition Facility (NIF). A wide range of diagnostics will be used to measure several parameters of implosion such as the core and fuel shape, temperatures and densities, and neutron yield. Accurate evaluations of the neutron and gamma backgrounds are important for several diagnostics, such as the High Energy X-ray Imager (HEXRI). Several Monte-Carlo simulations were performed to identify the expected signal to background ratios at several potential locations for the HEXRI diagnostics. Gamma backgrounds were significantly reduced by using tungsten collimators. The collimators resulted in the reduction of the gamma background at the HEXRI scintillators by more than an order of magnitude during the first 40 ns following a THD shot.

Khater, H; Dauffy, L; Tommasini, R; Eckart, M; Eder, D

2009-10-05T23:59:59.000Z

48

Systems and methods for detecting nuclear radiation in the presence of backgrounds  

DOE Patents [OSTI]

Systems and methods for the simultaneous detection and identification of radiation species, including neutrons, gammas/x-rays and minimum ionizing particles (MIPs). A plurality of rectangular and/or triangularly shaped radiation sensitive scintillators can be configured from a plurality of nano-sized particles, dopants and an extruded plastic material. A wavelength-shifting fiber can then be located within a central hole of each extruded scintillator, wherein the wavelength-shifting fiber absorbs scintillation light and re-emits the light at a longer wavelength, thereby piping the light to a photodetector whose response to the light indicates the presence of radiation The resulting method and system can simultaneously detect neutrons, gamma rays, x-rays and cosmic rays (MIPs) and identify each.

Bross, Alan D.; Mellott, Kerry L.; Pla-Dalmau, Anna

2005-06-21T23:59:59.000Z

49

Mass without radiation: heavily obscured AGN, the X-ray Background and the Black Hole Mass Density  

E-Print Network [OSTI]

A recent revision of black hole scaling relations (Kormendy & Ho 2013), indicates that the local mass density in black holes should be increased by up to a factor of five with respect to previously determined values. The local black hole mass density is connected to the mean radiative efficiency of accretion through the time integral of the AGN volume density and a significant increase of the local black holes mass density would have interesting consequences on AGN accretion properties and demography. One possibility to explain a large black hole mass density is that most of the Black Hole growth is via radiatively inefficient channels such as super Eddington accretion, however, given the intrinsic degeneracies in the Soltan argument, this solution is not unique. Here we show how it is possible to accommodate a larger fraction of heavily buried, Compton thick AGN, without violating the limit imposed by the hard X-ray and mid-infrared backgrounds spectral energy density.

Comastri, A; Marconi, A; Risaliti, G; Salvati, M

2015-01-01T23:59:59.000Z

50

High-level and transuranic radioactive wastes: Background information document for amendments to 40 CFR part 191  

SciTech Connect (OSTI)

The report provides the necessary background information technical analyses, and justifications in support of the proposed amendments to 40 CFR Part 191. The scope of the report encompasses the conceptual framework for assessing radiation exposures and associated health risks. In general terms, this assessment examines the radioactive source term characterization, analysis of the movement of radionuclides from the repository through the appropriate environmental exposure pathways and doses received by members of the general public. The report used transuranic waste for individual dose and ground-water protection analysis.

Not Available

1993-11-01T23:59:59.000Z

51

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

SciTech Connect (OSTI)

While scientists at CERN and other particle accelerators around the world explore the boundaries of high energy physics, the Majorana project investigates the other end of the spectrum with its extremely sensitive, low background, low energy detector. The MAJORANA DEMONSTRATOR aims to detect neutrinoless double beta decay (0???), a rare theoretical process in which two neutrons decay into two protons and two electrons, without the emission of the two antineutrinos that are a product of a normal double beta decay. This process is only possible if – and therefore a detection would prove — the neutrino is a Majorana particle, meaning that it is its own antiparticle [Aaselth et al. 2004] . The existence of such a decay would also disprove lepton conservation and give information about the neutrino's mass.

Greene, Austen T.; Orrell, John L.

2012-08-25T23:59:59.000Z

52

Background Radiation Survey of the Radiological/Nuclear Countermeasures Test and Evaluation Center  

SciTech Connect (OSTI)

In preparation for operations at the Radiological/Nuclear Countermeasures Test and Evaluation Complex (Rad/NucCTEC), the Department of Homeland Security Domestic Nuclear Detection Office (DHS/DNDO) requested that personnel from the Remote Sensing Laboratory (RSL) conduct a survey of the present radiological conditions at the facility. The measurements consist of the exposure rate from a high-pressure ion chamber (HPIC), high-resolution spectra from a high-purity germanium (HPGe) system in an in situ configuration, and low-resolution spectra from a sodium iodide (NaI) detector in a radiation detection backpack. Measurements with these systems were collected at discrete locations within the facility. Measurements were also collected by carrying the VECTOR backpack throughout the complex to generate a map of the entire area. The area was also to be surveyed with the Kiwi (an array of eight-2-inch x 4-inch x 16-inch NaI detectors) from the Aerial Measuring Systems; however, conflicts with test preparation activities at the site prevented this from being accomplished.

Colin Okada

2010-09-16T23:59:59.000Z

53

On the ultra high energy cosmic rays and the origin of the cosmic microwave background radiation  

E-Print Network [OSTI]

Some inconsistencies to the assumption of a cosmological origin of the cosmic microwave background CMB, such as the absence of gravitational lensing in the WMAP data, open the doors to some speculations such as a local origin to the CMB. We argue here that this assumption agrees with the absence of the GZK cutoff (at least according to AGASA data) in the energy spectrum of the cosmic ray due to the cosmic interaction with the CMB at $6\\times 10^{19} eV$ or above. Within 50 Mpc from Earth, the matter and light distributions are close to an anisotropic distribution, where the local cluster and local super-clusters of galaxies can be identified. In contrast, the ultra high energy comic rays data is consistent to an almost isotropic distribution, and there is no correlation between their arrival direction and astronomical sources within our local cluster. This means that the events above the GZK cutoff come from distances above 50 Mpc, without an apparent energy loss. This scenario is plausible under the assumption of the CMB concentrated only within 3-4 Mpc from Earth. In other words, the CMB has a local origin linked only to the local super-cluster of galaxies. In addition, the galactic and extragalactic energy spectra index within the energy equipartition theorem strongly constrains the dark matter and dark energy hypothesis, essential in the Big Bang cosmology.

C. E. Navia; C. R. A. Augusto; K. H. Tsui

2007-07-12T23:59:59.000Z

54

Lowering the background level and the energy threshold of Micromegas x-ray detectors for axion searches  

E-Print Network [OSTI]

Axion helioscopes search for solar axions by their conversion in x-rays in the presence of high magnetic fields. The use of low background x-ray detectors is an essential component contributing to the sensitivity of these searches. In this work, we review the recent advances on Micromegas detectors used in the CERN Axion Solar Telescope (CAST) and proposed for the future International Axion Observatory (IAXO). The actual setup in CAST has achieved background levels below 10$^{-6}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$, a factor 100 lower than the first generation of Micromegas detectors. This reduction is based on active and passive shielding techniques, the selection of radiopure materials, offline discrimination techniques and the high granularity of the readout. We describe in detail the background model of the detector, based on its operation at CAST site and at the Canfranc Underground Laboratory (LSC), as well as on Geant4 simulations. The best levels currently achieved at LSC are low than 10$^{-7}$ keV$^{-1}$ ...

Iguaz, F J; Aznar, F; Castel, J F; Dafni, T; Davenport, M; Ferrer-Ribas, E; Galan, J; Garcia, J A; Garza, J G; Giomataris, I; Irastorza, I G; Papaevangelou, T; Rodriguez, A; Tomas, A; Vafeiadis, T; Yildiz, S C

2015-01-01T23:59:59.000Z

55

Lowering the background level and the energy threshold of Micromegas x-ray detectors for axion searches  

E-Print Network [OSTI]

Axion helioscopes search for solar axions by their conversion in x-rays in the presence of high magnetic fields. The use of low background x-ray detectors is an essential component contributing to the sensitivity of these searches. In this work, we review the recent advances on Micromegas detectors used in the CERN Axion Solar Telescope (CAST) and proposed for the future International Axion Observatory (IAXO). The actual setup in CAST has achieved background levels below 10$^{-6}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$, a factor 100 lower than the first generation of Micromegas detectors. This reduction is based on active and passive shielding techniques, the selection of radiopure materials, offline discrimination techniques and the high granularity of the readout. We describe in detail the background model of the detector, based on its operation at CAST site and at the Canfranc Underground Laboratory (LSC), as well as on Geant4 simulations. The best levels currently achieved at LSC are low than 10$^{-7}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$ and show good prospects for the application of this technology in IAXO. Finally, we present some ideas and results for reducing the energy threshold of these detectors below 1 keV, using high-transparent windows, autotrigger electronics and studying the cluster shape at different energies. As a high flux of axion-like-particles is expected in this energy range, a sub-keV threshold detector could enlarge the physics case of axion helioscopes.

F. J. Iguaz; S. Aune; F. Aznar; J. F. Castel; T. Dafni; M. Davenport; E. Ferrer-Ribas; J. Galan; J. A. Garcia; J. G. Garza; I. Giomataris; I. G. Irastorza; T. Papaevangelou; A. Rodriguez; A. Tomas; T. Vafeiadis; S. C. Yildiz

2015-01-07T23:59:59.000Z

56

Unsterile-active neutrino mixing: Consequences on radiative decay and bounds from the x-ray background  

SciTech Connect (OSTI)

We consider a sterile neutrino to be an unparticle, namely, an unsterile neutrino, with anomalous dimension {eta} and study its mixing with a canonical active neutrino via a seesaw mass matrix. We show that there is no unitary transformation that diagonalizes the mixed propagator and a field redefinition is required. The propagating or 'mass' states correspond to an unsterilelike and activelike mode. The unsterile mode features a complex pole or resonance for 0{<=}{eta}<1/3 with an 'invisible width' which is the result of the decay of the unsterile mode into the active mode and the massless particles of the hidden conformal sector. For {eta}{>=}1/3, the complex pole disappears, merging with the unparticle threshold. The active mode is described by a stable pole, but 'inherits' a nonvanishing spectral density above the unparticle threshold as a consequence of the mixing. We find that the radiative decay width of the unsterile neutrino into the active neutrino (and a photon) via charged current loops, is suppressed by a factor {approx}[2sin{sup 2}({theta}{sub 0})(M{sup 2}/{lambda}{sup 2})]{sup {eta}}{sup /(1-{eta})}, where {theta}{sub 0} is the mixing angle for {eta}=0, M is approximately the mass of the unsterile neutrino, and {lambda}>>M is the unparticle scale. The suppression of the radiative (visible) decay width of the sterile neutrino weakens the bound on the mass and mixing angle from the x-ray or soft gamma-ray background.

Boyanovsky, D. [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Holman, R.; Hutasoit, Jimmy A. [Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States)

2009-07-15T23:59:59.000Z

57

Solid low-level radioactive waste radiation stability studies  

E-Print Network [OSTI]

properties and condition; on the other, on the specific features of thermal and radiation influences on it (Spitsyn et al. 1983). For the average composition of the fission products going to wastes repositories, the mean energy of irradiation may vary from... to the container determines, in part, the life of the container. Cormsion studies of containers by solidified wastes has indicated no problem areas in limited measurements to date; however very long-term effects have not been evaluated. The useful life...

Williams, Arnold Andre?

1989-01-01T23:59:59.000Z

58

Health effects of low-level radiation in shipyard workers. Final report: [Draft  

SciTech Connect (OSTI)

The Nuclear Shipyard Workers Study (NSWS) was designed to determine whether there is an excess risk of leukemia or other cancers associated with exposure to low levels of gamma radiation. The study compares the mortality experience of shipyard workers who qualified to work in radiation areas to the mortality of similar workers who hold the same types of jobs but who are not authorized to work in radiation areas. The population consists of workers from six government and two private shipyards.

Matanoski, G.M.

1991-06-01T23:59:59.000Z

59

Network-level fallout radiation-effects assessment. Final report  

SciTech Connect (OSTI)

The EMP Mitigation Program analyzes, and where feasible, lessens the degradation effects of EMP on national telecommunication resources. The program focuses on the resources of the public switched network (PSN) because the PSN comprises the largest, most diverse set of telecommunication assets in the United States and is the focus of National Security Emergency Preparedness (NSEP) telecommunication enhancement activities. Additionally, the majority of various organizations rely on the PSN to conduct their NSEP telecommunications responsibilities. Telecommunication equipment is most susceptible to high altitude EMP (HEMP) which occurs when a nuclear weapon is detonated at an altitude greater that 50 km above the earth's surface. In addition to studying the effects of EMP, the program has expanded to address the effects of fallout radiation and serve traffic congestion on the PSN.

Not Available

1989-05-12T23:59:59.000Z

60

Red shift in spectra of galaxies as a consequence of gravitational radiation of the same level as electromagnetic  

E-Print Network [OSTI]

In elaboration of the results presented earlier the red shift is also regarded in this investigation as a widening of electromagnetic radiation spectra, determined by the existence of gravitational radiation of a banded spectrum of the same level as electromagnetic.

S. I. Fisenko; I. S. Fisenko

2010-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Blazar Duty-Cycle at gamma-ray Frequecies: Constraints from Extragalactic Background Radiation and Prospects for AGILE and GLAST  

E-Print Network [OSTI]

We take into account the constraints from the observed extragalactic gamma-ray background to estimate the maximum duty cycle allowed for a selected sample of WMAP Blazars, in order to be detectable by AGILE and GLAST gamma-ray experiments. For the nominal sensitivity values of both instruments, we identify a subset of sources which can in principle be detectable also in a steady state without over-predicting the extragalactic background. This work is based on the results of a recently derived Blazar radio LogN-LogS obtained by combining several multi-frequency surveys.

Pittori, Carlotta; Colafrancesco, Sergio; Giommi, Paolo

2007-01-01T23:59:59.000Z

62

Blazar Duty-Cycle at gamma-ray Frequecies: Constraints from Extragalactic Background Radiation and Prospects for AGILE and GLAST  

E-Print Network [OSTI]

We take into account the constraints from the observed extragalactic gamma-ray background to estimate the maximum duty cycle allowed for a selected sample of WMAP Blazars, in order to be detectable by AGILE and GLAST gamma-ray experiments. For the nominal sensitivity values of both instruments, we identify a subset of sources which can in principle be detectable also in a steady state without over-predicting the extragalactic background. This work is based on the results of a recently derived Blazar radio LogN-LogS obtained by combining several multi-frequency surveys.

Carlotta Pittori; Elisabetta Cavazzuti; Sergio Colafrancesco; Paolo Giommi

2007-05-04T23:59:59.000Z

63

Radiative heating of the ISCCP upper level cloud regimes and its impact on the large-scale tropical circulation  

E-Print Network [OSTI]

Radiative heating of the ISCCP upper level cloud regimes and its impact on the large-scale tropical 2012; accepted 14 December 2012; published 31 January 2013. [1] Radiative heating profiles. The resulting radiative heating profiles have maxima of approximately 1 K/day near 12 km, with equal heating

64

New Limits to the IR Background: Bounds on Radiative Neutrino Decay and on VMO Contributions to the Dark Matter Problem  

E-Print Network [OSTI]

From considering the effect of gamma-gamma interactions on recently observed TeV gamma-ray spectra, improved limits are set to the density of extragalactic infrared (IR) photons which are robust and essentially model-independent. The resulting limits are up to two orders of magnitude more restrictive than direct observations in the 0.025-0.3eV regime. These limits are used to improve constraints on radiative neutrino decay in the mass range above 0.05eV and on Very Massive Objects (VMOs) as providing the dark matter needed to explain galaxy rotation curves.

S. D. Biller; J. Buckley; A. Burdett; J. Bussons Gordo; D. A. Carter-Lewis; D. J. Fegan; J. Findley; J. A. Gaidos; A. M. Hillas; F. Krennrich; R. C. Lamb; R. Lessard; J. E. McEnery; G. Mohanty; J. Quinn; A. J. Rodgers; H. J. Rose; F. Samuelson; G. Sembroski; P. Skelton; T. C. Weekes; J; Zweerink

1998-02-18T23:59:59.000Z

65

Energy levels and radiative transition rates for Ge XXXI, As XXXII, and Se XXXIII  

SciTech Connect (OSTI)

Fine-structure energies of the 67 levels belonging to the 1s{sup 2}, 1s 2l, 1s3l, 1s4l, 1s5l, and 1s6l configurations of Ge XXXI, As XXXII, and Se XXXIII have been calculated using the General-Purpose Relativistic Atomic Structure Package. In addition, radiative rates, oscillator strengths, transition wavelengths, and line strengths have been calculated for all electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transitions among these levels. Lifetimes are also presented for all excited levels of these three ions. We have compared our results with the results available in the literature and the accuracy of the data is assessed. We predict new energy levels, oscillator strengths, and transition probabilities where no other theoretical or experimental results are available, which will form the basis for future experimental work.

Aggarwal, Sunny, E-mail: sunny.du87@gmail.com; Singh, J.; Jha, A.K.S.; Mohan, Man

2014-07-15T23:59:59.000Z

66

Near-Core and In-Core Neutron Radiation Monitors for Real Time Neutron Flux Monitoring and Reactor Power Level Measurements  

SciTech Connect (OSTI)

MPFDs are a new class of detectors that utilize properties from existing radiation detector designs. A majority of these characteristics come from fission chamber designs. These include radiation hardness, gamma-ray background insensitivity, and large signal output.

Douglas S. McGregor; Marvin L. Adams; Igor Carron; Paul Nelson

2006-06-12T23:59:59.000Z

67

Chapter 5. Conclusion Uranium, a naturally occurring element, contributes to low levels of natural background radiation in the  

E-Print Network [OSTI]

are extracted from the earth. Protore is mined uranium ore that is not rich enough to meet the market demand conventional open-pit and underground uranium mining include overburden (although most overburden is not necessarily enriched in uranium as is protore), unreclaimed protore, waste rock, evaporites from mine water

68

Improving the Fermilab Booster Notching Efficiency, Beam Losses and Radiation Levels  

SciTech Connect (OSTI)

A fast vertical 1.08-m long kicker (notcher) located in the Fermilab Booster Long-05 straight section is currently used to remove 3 out of 84 circulating bunches after injection to generate an abort gap. With the maximum magnetic field of 72.5 Gauss, it removes only 87% of the 3-bunch intensity at 400 MeV, with 75% loss on pole tips of the focusing Booster magnets, 11% on the Long-06 collimators, and 1% in the rest of the ring. We propose to improve the notching efficiency and reduce beam loss in the Booster by using three horizontal kickers in the Long-12 section. STRUCT calculations show that using horizontal notchers, one can remove up to 96% of the 3-bunch intensity at 400-700 MeV, directing 95% of it to a new beam dump at the Long-13 section. This fully decouples notching and collimation. The beam dump absorbs most of the impinging proton energy in its jaws. The latter are encapsulated into an appropriate radiation shielding that reduces impact on the machine components, personnel and environment to the tolerable levels. MARS simulations show that corresponding prompt and residual radiation levels can be reduced ten times compared to the current ones.

Rakhno, I.L.; Drozhdin, A.I.; Mokhov, N.V.; Sidorov, V.I.; Tropin, I.S.; /Fermilab

2012-05-14T23:59:59.000Z

69

Energy levels, radiative rates and electron impact excitation rates for transitions in C III  

E-Print Network [OSTI]

We report energy levels, radiative rates (A-values) and lifetimes for the astrophysically-important Be-like ion C III. For the calculations, 166 levels belonging to the $n \\le$ 5 configurations are considered and the {\\sc grasp} (General-purpose Relativistic Atomic Structure Package) is adopted. Einstein A-coefficients are provided for all E1, E2, M1 and M2 transitions, while lifetimes are compared with available measurements as well as theoretical results, and no large discrepancies noted. Our energy levels are assessed to be accurate to better than 1\\% for a majority of levels, and A-values to better than 20\\% for most transitions. Collision strengths are also calculated, for which the Dirac Atomic R-matrix Code ({\\sc darc}) is used. A wide energy range, up to 21 Ryd, is considered and resonances resolved in a fine energy mesh in the thresholds region. The collision strengths are subsequently averaged over a Maxwellian velocity distribution to determine effective collision strengths up to a temperature of 8...

Aggarwal, K M

2015-01-01T23:59:59.000Z

70

Radiative Heating of the ISCCP Upper Level Cloud Regimes and its Impact on the Large-scale Tropical Circulation  

SciTech Connect (OSTI)

Radiative heating profiles of the International Satellite Cloud Climatology Project (ISCCP) cloud regimes (or weather states) were estimated by matching ISCCP observations with radiative properties derived from cloud radar and lidar measurements from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) sites at Manus, Papua New Guinea, and Darwin, Australia. Focus was placed on the ISCCP cloud regimes containing the majority of upper level clouds in the tropics, i.e., mesoscale convective systems (MCSs), deep cumulonimbus with cirrus, mixed shallow and deep convection, and thin cirrus. At upper levels, these regimes have average maximum cloud occurrences ranging from 30% to 55% near 12 km with variations depending on the location and cloud regime. The resulting radiative heating profiles have maxima of approximately 1 K/day near 12 km, with equal heating contributions from the longwave and shortwave components. Upper level minima occur near 15 km, with the MCS regime showing the strongest cooling of 0.2 K/day and the thin cirrus showing no cooling. The gradient of upper level heating ranges from 0.2 to 0.4 K/(day?km), with the most convectively active regimes (i.e., MCSs and deep cumulonimbus with cirrus) having the largest gradient. When the above heating profiles were applied to the 25-year ISCCP data set, the tropics-wide average profile has a radiative heating maximum of 0.45Kday-1 near 250 hPa. Column-integrated radiative heating of upper level cloud accounts for about 20% of the latent heating estimated by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR). The ISCCP radiative heating of tropical upper level cloud only slightly modifies the response of an idealized primitive equation model forced with the tropics-wide TRMM PR latent heating, which suggests that the impact of upper level cloud is more important to large-scale tropical circulation variations because of convective feedbacks rather than direct forcing by the cloud radiative heating profiles. However, the height of the radiative heating maxima and gradient of the heating profiles are important to determine the sign and patterns of the horizontal circulation anomaly driven by radiative heating at upper levels.

Li, Wei; Schumacher, Courtney; McFarlane, Sally A.

2013-01-31T23:59:59.000Z

71

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

SciTech Connect (OSTI)

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.

Carsten, A.L.

1984-01-01T23:59:59.000Z

72

Report on policy and activities concerning public awareness of health effects of low-level radiation  

SciTech Connect (OSTI)

In the summer of 1986, the Executive Committee authorized a study limited to determining policy and practices relevant to dissemination of information to the public on radiation health effects in three federal agencies. This report summarizes findings on two broad questions related to the communication issue: What, if any, are the policies under which federal agencies operate in disseminating information on health effects of radiation and what are the current programs and activities designed to provide the public information on health effects of radiation.

NONE

1986-11-01T23:59:59.000Z

73

Energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 21?Z?28  

SciTech Connect (OSTI)

We report calculations of energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 21?Z?28. The General-Purpose Relativistic Atomic Structure Package is adopted for calculating energy levels and radiative rates, while for determining the collision strengths and subsequently the excitation rates, the Dirac Atomic R-matrix Code is used. Oscillator strengths, radiative rates, and line strengths are listed for all E1, E2, M1, and M2 transitions among the lowest 24 levels of the Li-like ions considered. Collision strengths have been averaged over a Maxwellian velocity distribution, and the effective collision strengths obtained are given over a wide temperature range up to 10{sup 7.8} K. Additionally, lifetimes are listed for all calculated levels of these ions. Finally, extensive comparisons are made with results available in the literature, as well as with our analogous calculations for all parameters with the Flexible Atomic Code, in order to assess the accuracy of the results.

Aggarwal, Kanti M., E-mail: K.Aggarwal@qub.ac.uk; Keenan, Francis P.

2012-11-15T23:59:59.000Z

74

Energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 12?Z?20  

SciTech Connect (OSTI)

We report calculations of energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 12?Z?20. The GRASP (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates, while for determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code is used. Oscillator strengths, radiative rates, and line strengths are reported for all E1, E2, M1, and M2 transitions among the lowest 24 levels of the Li-like ions considered. Collision strengths have been averaged over a Maxwellian velocity distribution, and the effective collision strengths obtained are reported over a wide temperature range up to 10{sup 7.4} K. Additionally, lifetimes are also listed for all calculated levels of the ions. Finally, extensive comparisons are made with results available in the literature, as well as with our parallel calculations for all parameters with the Flexible Atomic Code, in order to assess the accuracy of the reported results.

Aggarwal, Kanti M., E-mail: K.Aggarwal@qub.ac.uk; Keenan, Francis P.

2013-03-15T23:59:59.000Z

75

Radiation dose assessments to support evaluations of radiological control levels for recycling or reuse of materials and equipment  

SciTech Connect (OSTI)

Pacific Northwest Laboratory is providing Environmental Protection Support and Assistance to the USDOE, Office of Environmental Guidance. Air, Water, and Radiation Division. As part of this effort, PNL is collecting data and conducting technical evaluations to support DOE analyses of the feasibility of developing radiological control levels for recycling or reuse of metals, concrete, or equipment containing residual radioactive contamination from DOE operations. The radiological control levels will be risk-based, as developed through a radiation exposure scenario and pathway analysis. The analysis will include evaluation of relevant radionuclides, potential mechanisms of exposure, and both health and non-health-related impacts. The main objective of this report is to develop a methodology for establishing radiological control levels for recycle or reuse. This report provides the results of the radiation exposure scenario and pathway analyses for 42 key radionuclides generated during DOE operations that may be contained in metals or equipment considered for either recycling or reuse. The scenarios and information developed by the IAEA. Application of Exemption Principles to the Recycle and Reuse of Materials from Nuclear Facilities, are used as the initial basis for this study. The analyses were performed for both selected worker populations at metal smelters and for the public downwind of a smelter facility. Doses to the public downwind were estimated using the US (EPA) CAP88-PC computer code with generic data on atmospheric dispersion and population density. Potential non-health-related effects of residual activity on electronics and on film were also analyzed.

Hill, R.L.; Aaberg, R.L.; Baker, D.A.; Kennedy, W.E. Jr.

1995-07-01T23:59:59.000Z

76

System level latchup mitigation for single event and transient radiation effects on electronics  

DOE Patents [OSTI]

A ``blink`` technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements. 18 figs.

Kimbrough, J.R.; Colella, N.J.

1997-09-30T23:59:59.000Z

77

System level latchup mitigation for single event and transient radiation effects on electronics  

DOE Patents [OSTI]

A "blink" technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements.

Kimbrough, Joseph Robert (Pleasanton, CA); Colella, Nicholas John (Livermore, CA)

1997-01-01T23:59:59.000Z

78

ESTIMATING GROUND-LEVEL SOLAR RADIATION AND EVAPOTRANSPIRATION IN PUERTO RICO  

E-Print Network [OSTI]

REMOTE SENSING Eric. W. Harmsen1 , John Mecikalski2 , Vanessa Acaron3 and Jayson Maldonado3 1 Department insolation, other meteorological variables (e.g., net radiation, soil heat flux, air temperature dew point remote sensing product. As a practical example of the use of the methodology, the Hargraeves-Samani ETo

Gilbes, Fernando

79

Hubble diagrams of soft and hard radiation sources in the graviton background: to an apparent contradiction between supernova 1a and gamma-ray burst observations  

E-Print Network [OSTI]

In the sea of super-strong interacting gravitons, non-forehead collisions with gravitons deflect photons, and this deflection may differ for soft and hard radiations. As a result, the Hubble diagram would not be a universal function and it will have a different view for such sources as supernovae in visible light and gamma-ray bursts. Observations of these two kinds are compared here with the limit cases of the Hubble diagram.

Michael A. Ivanov

2007-01-10T23:59:59.000Z

80

Earth X-ray albedo for cosmic X-ray background radiation in the 1--1000 keV band  

E-Print Network [OSTI]

We present calculations of the reflection of the cosmic X-ray background (CXB) by the Earth's atmosphere in the 1--1000 keV energy range. The calculations include Compton scattering and X-ray fluorescent emission and are based on a realistic chemical composition of the atmosphere. Such calculations are relevant for CXB studies using the Earth as an obscuring screen (as was recently done by INTEGRAL). The Earth's reflectivity is further compared with that of the Sun and the Moon -- the two other objects in the Solar system subtending a large solid angle on the sky, as needed for CXB studies.

E. Churazov; S. Sazonov; R. Sunyaev; M. Revnivtsev

2008-02-11T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Health physics manual of good practices for reducing radiation exposure to levels that are as low as reasonably achievable (ALARA)  

SciTech Connect (OSTI)

A primary objective of the US Department of Energy (DOE) health physics and radiation protection program has been to limit radiation exposures to those levels that are as low as reasonably achievable (ALARA). As a result, the ALARA concept developed into a program and a set of operational principles to ensure that the objective was consistently met. Implementation of these principles required that a guide be produced. The original ALARA guide was issued by DOE in 1980 to promote improved understanding of ALARA concepts within the DOE community and to assist those responsible for operational ALARA activities in attaining their goals. Since 1980, additional guidance has been published by national and international organizations to provide further definition and clarification to ALARA concepts. As basic ALARA experience increased, the value and role of the original guide prompted the DOE Office of Nuclear Safety (ONS) to support a current revision. The revised manual of good practices includes six sections: 1.0 Introduction, 2.0 Administration, 3.0 Optimization, 4.0 Setting and Evaluating ALARA Goals, 5.0 Radiological Design, and 6.0 Conduct of Operations. The manual is directed primarily to contractor and DOE staff who are responsible for conduct and overview of radiation protection and ALARA programs at DOE facilities. The intent is to provide sufficient guidance such that the manual, if followed, will ensure that radiation exposures are maintained as low as reasonably achievable and will establish the basis for a formally structured and auditable program. 118 refs., 16 figs., 3 tabs.

Herrington, W.N.; Higby, D.P.; Kathren,., R.L.; Merwin, S.E.; Stoetzel, G.A.

1988-06-01T23:59:59.000Z

82

Minimizing the background radiation in the new neutron time-of-flight facility at CERN FLUKA Monte Carlo simulations for the optimization of the n_TOF second experimental line  

E-Print Network [OSTI]

At the particle physics laboratory CERN in Geneva, Switzerland, the Neutron Time-of-Flight facility has recently started the construction of a second experimental line. The new neutron beam line will unavoidably induce radiation in both the experimental area and in nearby accessible areas. Computer simulations for the minimization of the background were carried out using the FLUKA Monte Carlo simulation package. The background radiation in the new experimental area needs to be kept to a minimum during measurements. This was studied with focus on the contributions from backscattering in the beam dump. The beam dump was originally designed for shielding the outside area using a block of iron covered in concrete. However, the backscattering was never studied in detail. In this thesis, the fluences (i.e. the flux integrated over time) of neutrons and photons were studied in the experimental area while the beam dump design was modified. An optimized design was obtained by stopping the fast neutrons in a high Z mat...

Bergström, Ida; Elfgren, Erik

2013-06-11T23:59:59.000Z

83

CONTRIBUTION OF GAMMA-RAY-LOUD RADIO GALAXIES' CORE EMISSIONS TO THE COSMIC MeV AND GeV GAMMA-RAY BACKGROUND RADIATION  

SciTech Connect (OSTI)

The Fermi gamma-ray satellite has recently detected gamma-ray emissions from radio galaxy cores. From these samples, we first examine the correlation between the luminosities at 5 GHz, L{sub 5GHz}, and at 0.1-10 GeV, L{sub {gamma}}, of gamma-ray-loud radio galaxies. We find that the correlation is significant with L{sub {gamma}}{proportional_to}L{sup 1.16}{sub 5GHz} based on a partial correlation analysis. Using this correlation and the radio luminosity function (RLF) of radio galaxies, we explore the contribution of gamma-ray-loud radio galaxies to the unresolved extragalactic gamma-ray background (EGRB). The gamma-ray luminosity function is obtained by normalizing the RLF to reproduce the source-count distribution of the Fermi gamma-ray-loud radio galaxies. We find that gamma-ray-loud radio galaxies can explain {approx}25% of the unresolved Fermi EGRB flux above 100 MeV and will also make a significant contribution to the EGRB in the 1-30 MeV energy band. Since blazars explain 22% of the EGRB above 100 MeV, radio-loud active galactic nucleus populations explain {approx}47% of the unresolved EGRB. We further make an interpretation on the origin of the EGRB. The observed EGRB spectrum at 0.2-100 GeV does not show an absorption signature by the extragalactic background light. Thus, the dominant population of the origin of EGRB at very high energy (>30 GeV) might be either nearby gamma-ray-emitting sources or sources with very hard gamma-ray spectra.

Inoue, Yoshiyuki, E-mail: yinoue@kusastro.kyoto-u.ac.jp [Department of Astronomy, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan)

2011-05-20T23:59:59.000Z

84

The Association between Cancers and Low Level Radiation: an evaluation of the epidemiological evidence at the Hanford Nuclear Weapons Facility  

E-Print Network [OSTI]

indiv. indiv. Gilbertetal. (Hanford & Combined) Gilbertetal.on both radiation and the Hanford facility. The data used toG. Radiation exposures of Hanford workers dying from cancer

Britton, Julie

2010-01-01T23:59:59.000Z

85

Background canceling surface alpha detector  

DOE Patents [OSTI]

A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone. 5 figs.

MacArthur, D.W.; Allander, K.S.; Bounds, J.A.

1996-06-11T23:59:59.000Z

86

Impact of Ultrahigh Baseline PSA Levels on Biochemical and Clinical Outcomes in Two Radiation Therapy Oncology Group Prostate Clinical Trials  

SciTech Connect (OSTI)

Purpose: To assess ultrahigh (UH; prostate-specific antigen [PSA]levels {>=}50 ng/ml) patient outcomes by comparison to other high-risk patient outcomes and to identify outcome predictors. Methods and Materials: Prostate cancer patients (PCP) from two Phase III Radiation Therapy Oncology Group clinical trials (studies 9202 and 9413) were divided into two groups: high-risk patients with and without UH baseline PSA levels. Predictive variables included age, Gleason score, clinical T stage, Karnofsky performance score, and treatment arm. Outcomes included overall survival (OS), distant metastasis (DM), and biochemical failure (BF). Unadjusted and adjusted hazard ratios (HRs) were calculated using either the Cox or Fine and Gray's regression model with associated 95% confidence intervals (CI) and p values. Results: There were 401 patients in the UH PSA group and 1,792 patients in the non-UH PSA PCP group of a total of 2,193 high-risk PCP. PCP with UH PSA were found to have inferior OS (HR, 1.19; 95% CI, 1.02-1.39, p = 0.02), DM (HR, 1.51; 95% CI, 1.19-1.92; p = 0.0006), and BF (HR, 1.50; 95% CI, 1.29-1.73; p < 0.0001) compared to other high-risk PCP. In the UH cohort, PSA level was found to be a significant factor for the risk of DM (HR, 1.01; 95% CI, 1.001-1.02) but not OS and BF. Gleason grades of 8 to 10 were found to consistently predict for poor OS, DM, and BF outcomes (with HR estimates ranging from 1.41-2.36) in both the high-risk cohort and the UH cohort multivariable analyses. Conclusions: UH PSA levels at diagnosis are related to detrimental changes in OS, DM, and BF. All three outcomes can be modeled by various combinations of all predictive variables tested.

Rodrigues, George, E-mail: george.rodrigues@lhsc.on.c [Department of Oncology, University of Western Ontario, London, Ontario (Canada); Bae, Kyounghwa [Department of Statistics, Radiation Therapy Oncology Group, Philadelphia, Pennsylvania (United States); Roach, Mack [Department of Radiation Oncology, University of California San Francisco, San Francisco, California (United States); Lawton, Colleen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Donnelly, Bryan [Department of Surgical Oncology, University of Calgary, Calgary, Alberta (Canada); Grignon, David [Department of Pathology, Indiana Pathology Institute, Indianapolis, Indiana (United States); Hanks, Gerald [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Porter, Arthur [Department of Oncology, McGill University Health Centre, Montreal, Quebec (Canada); Lepor, Herbert [Department of Urology, NY University Langone Medical Center, New York, New York (United States); Sandler, Howard [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States)

2011-06-01T23:59:59.000Z

87

The frequency of tropopause-level thick and thin cirrus clouds as observed by CALIPSO and the relationship to relative humidity and outgoing longwave radiation  

E-Print Network [OSTI]

schematic of the location of the SPCZ and the ITCZ in the Pacific Ocean................................................... 40 3 Three month average of outgoing longwave radiation (OLR) for DJF provided by the NOAA/OAR/ESRL PSD... THE FREQUENCY OF TROPOPAUSE-LEVEL THICK AND THIN CIRRUS CLOUDS AS OBSERVED BY CALIPSO AND THE RELATIONSHIP TO RELATIVE HUMIDITY AND OUTGOING LONGWAVE RADIATION A Thesis by ALLISON L. CARDONA Submitted to the Office of Graduate...

Cardona, Allison Leanne

2008-10-10T23:59:59.000Z

88

Cros S., Wald L., 2003. Survey of the main databases providing solar radiation data at ground level. In Proceedings of the 23rd EARSeL Annual Symposium "Remote Sensing in Transition", 2-4 June 2003, Ghent,  

E-Print Network [OSTI]

Cros S., Wald L., 2003. Survey of the main databases providing solar radiation data at ground level providing solar radiation data at the ground level S. Cros & L. Wald Remote Sensing and Modeling Group, Ecole des Mines de Paris, France Keywords: solar radiation, database, information system, climatology

Paris-Sud XI, Université de

89

Statistical correlation between hourly and daily values of solar radiation on horizontal surface at sea level in the Italian climate  

E-Print Network [OSTI]

219- Statistical correlation between hourly and daily values of solar radiation on horizontal- nalières du rayonnement solaire. Abstract. 2014 The knowledge of hourly data of solar radiation is required data measured in Italian stations and propose a method to estimate hourly solar radiation

Boyer, Edmond

90

Cosmic Background Radiation Mini-Review  

E-Print Network [OSTI]

This is a complete re-write of the mini-review for the Review of Particle Physics (a.k.a the Partcicle Data Book), which includes an assessment of the CMB anisotropy results and their interpretation up until the end of 2003. It forms a compact overview of the field at this time. Sections headings are: Introduction; Description of CMB Anisotropies; Cosmological Parameters; Physics of Anisotropies; Current Anisotropy Data; CMB Polarization; Complications; Constraints on Cosmologies; Particle Physics Constraints; Fundamental Lessons; and Future Directions.

Douglas Scott; George Smoot

2004-06-24T23:59:59.000Z

91

Lefvre M., Cros S., Albuisson M., Wald L., 2003. Developing a database using Meteosat data for the de-livery of solar radiation assessments at ground level. In Proceedings of the 23rd EARSeL Annual Symposium  

E-Print Network [OSTI]

for the de- livery of solar radiation assessments at ground level. In Proceedings of the 23rd EARSeL Annual, Meteosat, solar radiation, climatology, database, information system ABSTRACT: An information system, called HelioClim, is offered for answering the needs for long-term time-series of solar radiation data

Paris-Sud XI, Université de

92

Gabriele Simi1 BaBar SVT: Radiation Damage and BaBar SVT: Radiation Damage and  

E-Print Network [OSTI]

-shelled into place after installation of B1 magnets Radiation exposure at innermost layer (nominal background level was originally designed to function in up to 10 X nominal background. #12;Gabriele Simi5 DesignDesign Double sided nbulk silcon sensors, 630 k cm Custom frontend chips (honeywell 0.8 m) Arch shaped outer layer

California at Santa Cruz, University of

93

Estimating the risks of cancer mortality and genetic defects resulting from exposures to low levels of ionizing radiation  

SciTech Connect (OSTI)

Estimators for calculating the risk of cancer and genetic disorders induced by exposure to ionizing radiation have been recommended by the US National Academy of Sciences Committee on the Biological Effects of Ionizing Radiations, the UN Scientific Committee on the Effects of Atomic Radiation, and the International Committee on Radiological Protection. These groups have also considered the risks of somatic effects other than cancer. The US National Council on Radiation Protection and Measurements has discussed risk estimate procedures for radiation-induced health effects. The recommendations of these national and international advisory committees are summarized and compared in this report. Based on this review, two procedures for risk estimation are presented for use in radiological assessments performed by the US Department of Energy under the National Environmental Policy Act of 1969 (NEPA). In the first procedure, age- and sex-averaged risk estimators calculated with US average demographic statistics would be used with estimates of radiation dose to calculate the projected risk of cancer and genetic disorders that would result from the operation being reviewed under NEPA. If more site-specific risk estimators are needed, and the demographic information is available, a second procedure is described that would involve direct calculation of the risk estimators using recommended risk-rate factors. The computer program REPCAL has been written to perform this calculation and is described in this report. 25 references, 16 tables.

Buhl, T.E.; Hansen, W.R.

1984-05-01T23:59:59.000Z

94

Cellular and molecular research to reduce uncertainties in estimates of health effects from low-level radiation  

SciTech Connect (OSTI)

A study was undertaken by five radiation scientists to examine the feasibility of reducing the uncertainties in the estimation of risk due to protracted low doses of ionizing radiation. In addressing the question of feasibility, a review was made by the study group: of the cellular, molecular, and mammalian radiation data that are available; of the way in which altered oncogene properties could be involved in the loss of growth control that culminates in tumorigenesis; and of the progress that had been made in the genetic characterizations of several human and animal neoplasms. On the basis of this analysis, the study group concluded that, at the present time, it is feasible to mount a program of radiation research directed at the mechanism(s) of radiation-induced cancer with special reference to risk of neoplasia due to protracted, low doses of sparsely ionizing radiation. To implement a program of research, a review was made of the methods, techniques, and instruments that would be needed. This review was followed by a survey of the laboratories and institutions where scientific personnel and facilities are known to be available. A research agenda of the principal and broad objectives of the program is also discussed. 489 refs., 21 figs., 14 tabs.

Elkind, M.M.; Bedford, J.; Benjamin, S.A.; Waldren, C.A. (Colorado State Univ., Fort Collins, CO (USA)); Gotchy, R.L. (Science Applications International Corp., McLean, VA (USA))

1990-10-01T23:59:59.000Z

95

Patient radiation doses in interventional cardiology in the U.S.: Advisory data sets and possible initial values for U.S. reference levels  

SciTech Connect (OSTI)

Purpose: To determine patient radiation doses from interventional cardiology procedures in the U.S and to suggest possible initial values for U.S. benchmarks for patient radiation dose from selected interventional cardiology procedures [fluoroscopically guided diagnostic cardiac catheterization and percutaneous coronary intervention (PCI)]. Methods: Patient radiation dose metrics were derived from analysis of data from the 2008 to 2009 Nationwide Evaluation of X-ray Trends (NEXT) survey of cardiac catheterization. This analysis used deidentified data and did not require review by an IRB. Data from 171 facilities in 30 states were analyzed. The distributions (percentiles) of radiation dose metrics were determined for diagnostic cardiac catheterizations, PCI, and combined diagnostic and PCI procedures. Confidence intervals for these dose distributions were determined using bootstrap resampling. Results: Percentile distributions (advisory data sets) and possible preliminary U.S. reference levels (based on the 75th percentile of the dose distributions) are provided for cumulative air kerma at the reference point (K{sub a,r}), cumulative air kerma-area product (P{sub KA}), fluoroscopy time, and number of cine runs. Dose distributions are sufficiently detailed to permit dose audits as described in National Council on Radiation Protection and Measurements Report No. 168. Fluoroscopy times are consistent with those observed in European studies, but P{sub KA} is higher in the U.S. Conclusions: Sufficient data exist to suggest possible initial benchmarks for patient radiation dose for certain interventional cardiology procedures in the U.S. Our data suggest that patient radiation dose in these procedures is not optimized in U.S. practice.

Miller, Donald L.; Hilohi, C. Michael; Spelic, David C. [Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States)

2012-10-15T23:59:59.000Z

96

Radiation: Facts, Risks and Realities  

E-Print Network [OSTI]

of Radiation 3 Understanding Radiation Risks 6 Naturally Occurring (Background) Radiation 7 Man-Made Radiation, beta particles and gamma rays. Other types, such as x-rays, can occur naturally or be machine-produced. Scientists have also learned that radiation sources are naturally all around us. Radiation can come from

97

Illuminating the background : topics in cosmic microwave background polarization research  

E-Print Network [OSTI]

results in electric dipole radiation. For an unpolarizedincom- ing radiation. Because the electric field oscillates,

Miller, Nathan James

2012-01-01T23:59:59.000Z

98

Estimating radiological background using imaging spectroscopy  

SciTech Connect (OSTI)

Optical imaging spectroscopy is investigated as a method to estimate radiological background by spectral identification of soils, sediments, rocks, minerals and building materials derived from natural materials and assigning tabulated radiological emission values to these materials. Radiological airborne surveys are undertaken by local, state and federal agencies to identify the presence of radiological materials out of regulatory compliance. Detection performance in such surveys is determined by (among other factors) the uncertainty in the radiation background; increased knowledge of the expected radiation background will improve the ability to detect low-activity radiological materials. Radiological background due to naturally occurring radiological materials (NORM) can be estimated by reference to previous survey results, use of global 40K, 238U, and 232Th (KUT) values, reference to existing USGS radiation background maps, or by a moving average of the data as it is acquired. Each of these methods has its drawbacks: previous survey results may not include recent changes, the global average provides only a zero-order estimate, the USGS background radiation map resolutions are coarse and are accurate only to 1 km – 25 km sampling intervals depending on locale, and a moving average may essentially low pass filter the data to obscure small changes in radiation counts. Imaging spectroscopy from airborne or spaceborne platforms can offer higher resolution identification of materials and background, as well as provide imaging context information. AVIRIS hyperspectral image data is analyzed using commercial exploitation software to determine the usefulness of imaging spectroscopy to identify qualitative radiological background emissions when compared to airborne radiological survey data.

Bernacki, Bruce E.; Schweppe, John E.; Stave, Sean C.; Jordan, David V.; Kulisek, Jonathan A.; Stewart, Trevor N.; Seifert, Carolyn E.

2014-06-13T23:59:59.000Z

99

Radiation site cleanup regulations: Technical support document for the development of radionuclide cleanup levels for soil. Review draft  

SciTech Connect (OSTI)

This report presents EPA`s approach to assessing some of the beneficial and adverse radiation health effects associated with various possible values for an annual dose limit. In particular, it discusses the method developed to determine how the choice of cleanup criterion affects (1) the time-integrated numbers of non-fatal and fatal radiogenic cancers averted among future populations, (2) the occurrence of radiogenic cancers among remediation workers and the public caused by the cleanup process itself, and (3) the volume of contaminated soil that may require remediation.

Wolbarst, A.B.; Mauro, J.; Anigstein, R.; Back, D.; Bartlett, J.W.

1994-09-24T23:59:59.000Z

100

Disturbance of DKK1 level is partly involved in survival of lung cancer cells via regulation of ROMO1 and ?-radiation sensitivity  

SciTech Connect (OSTI)

Highlights: •DKK1 was expressed differently among non-small-cell lung cancer cell lines. •DKK1 negatively regulated ROMO1 gene expression. •Disturbance of DKK1 level induced the imbalance of cellular ROS. •DKK1/ROMO1-induced ROS imbalance is involved in cell survival in NSCLC. -- Abstract: Dickkopf1 (DKK1), a secreted protein involved in embryonic development, is a potent inhibitor of the Wnt signaling pathway and has been postulated to be a tumor suppressor or tumor promoter depending on the tumor type. In this study, we showed that DKK1 was expressed differently among non-small-cell lung cancer cell lines. The DKK1 expression level was much higher in A549 cells than in H460 cells. We revealed that blockage of DKK1 expression by silencing RNA in A549 cells caused up-regulation of intracellular reactive oxygen species (ROS) modulator (ROMO1) protein, followed by partial cell death, cell growth inhibition, and loss of epithelial–mesenchymal transition property caused by ROS, and it also increased ?-radiation sensitivity. DKK1 overexpression in H460 significantly inhibited cell survival with the decrease of ROMO1 level, which induced the decrease of cellular ROS. Thereafter, exogenous N-acetylcysteine, an antioxidant, or hydrogen peroxide, a pro-oxidant, partially rescued cells from death and growth inhibition. In each cell line, both overexpression and blockage of DKK1 not only elevated p-RB activation, which led to cell growth arrest, but also inactivated AKT/NF-kB, which increased radiation sensitivity and inhibited cell growth. This study is the first to demonstrate that strict modulation of DKK1 expression in different cell types partially maintains cell survival via tight regulation of the ROS-producing ROMO1 and radiation resistance.

Kim, In Gyu, E-mail: igkim@kaeri.re.kr [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, University of Science and Technology (UST), 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Seo Yoen [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of) [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Biomedical Translational Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Kim, Hyun A; Kim, Jeong Yul [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of)] [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Lee, Jae Ha; Choi, Soo Im [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of) [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, University of Science and Technology (UST), 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Han, Jeong Ran; Kim, Kug Chan [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of)] [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon 305-600 (Korea, Republic of); Cho, Eun Wie [Biomedical Translational Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of)] [Biomedical Translational Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of)

2014-01-03T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

ORIGINAL PAPER Tree rings reveal extent of exposure to ionizing radiation  

E-Print Network [OSTI]

Pinus sylvestris located near Chernobyl, Ukraine, varying in the level of background radiation by almost in smaller trees. These findings suggest that radiation has suppressed growth rates of pines in Chernobyl their growth tra- jectories in complex ways. Keywords Chernobyl Á Growth Á Interaction between stressors Á

Mousseau, Timothy A.

102

Low Background Counting At SNOLAB  

SciTech Connect (OSTI)

It is a continuous and ongoing effort to maintain radioactivity in materials and in the environment surrounding most underground experiments at very low levels. These low levels are required so that experiments can achieve the required detection sensitivities for the detection of low-energy neutrinos, searches for dark matter and neutrinoless double-beta decay. SNOLAB has several facilities which are used to determine these low background levels in the materials and the underground environment. This proceedings will describe the SNOLAB High Purity Germanium Detector which has been in continuous use for the past five years and give results of many of the items that have been counted over that period. Brief descriptions of SNOLAB's alpha-beta and electrostatic counters will be given, and the radon levels at SNOLAB will be discussed.

Lawson, Ian; Cleveland, Bruce [SNOLAB, 1039 Regional Rd 24, Lively, ON P3Y 1N2 (Canada)

2011-04-27T23:59:59.000Z

103

INSTALLATION OF A POST-ACCIDENT CONFINEMENT HIGH-LEVEL RADIATION MONITORING SYSTEM IN THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA  

SciTech Connect (OSTI)

This is the final report on the INSP project entitled, ``Post-Accident Confinement High-Level Radiation Monitoring System'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.6 (Attachment 1). This project was initiated in February 1993 to assist the Russians in reducing risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Unit 2, through improved accident detection capability, specifically by the installation of a dual train high-level radiation detection system in the confinement of Unit 2 of the Kola NPP. The major technical objective of this project was to provide, install and make operational the necessary hardware inside the confinement of the Kola NPP Unit 2 to provide early and reliable warning of the release of radionuclides from the reactor into the confinement air space as an indication of the occurrence of a severe accident at the plant. In addition, it was intended to provide hands-on experience and training to the Russian plant workers in the installation, operation, calibration and maintenance of the equipment in order that they may use the equipment without continued US assistance as an effective measure to improve reactor safety at the plant.

GREENE,G.A.; GUPPY,J.G.

1998-09-01T23:59:59.000Z

104

Energy levels, oscillator strengths, and radiative rates for Si-like Zn XVII, Ga XVIII, Ge XIX, and As XX  

SciTech Connect (OSTI)

The energy levels, oscillator strengths, line strengths, and transition probabilities for transitions among the terms belonging to the 3s{sup 2}3p{sup 2}, 3s3p{sup 3}, 3s{sup 2}3p3d, 3s{sup 2}3p4s, 3s{sup 2}3p4p and 3s{sup 2}3p4d configurations of silicon-like ions (Zn XVII, Ga XVIII, Ge XIX, and As XX) have been calculated using the configuration-interaction code CIV3. The calculations have been carried out in the intermediate coupling scheme using the Breit–Pauli Hamiltonian. The present calculations have been compared with the available experimental data and other theoretical calculations. Most of our calculations of energy levels and oscillator strengths (in length form) show good agreement with both experimental and theoretical data. Lifetimes of the excited levels have also been calculated. -- Highlights: •We have calculated the fine-structure energy levels of Si-like Zn, Ga, Ge and As. •The calculations are performed using the configuration interaction method (CIV3). •We have calculated the oscillator strengths, line strengths and transition rates. •The wavelengths of the transitions are listed in this article. •We also have made comparisons between our data and other calculations.

Abou El-Maaref, A., E-mail: aahmh@hotmail.com [Physics Department, Faculty of Science, Al-Azhar University, Assuit (Egypt); Allam, S.H.; El-Sherbini, Th.M. [Laboratory of Lasers and New Materials, Physics Department, Faculty of Science, Cairo University, Giza (Egypt)] [Laboratory of Lasers and New Materials, Physics Department, Faculty of Science, Cairo University, Giza (Egypt)

2014-01-15T23:59:59.000Z

105

Radiation Exposure in Biliary Procedures Performed to Manage Anastomotic Strictures in Pediatric Liver Transplant Recipients: Comparison Between Radiation Exposure Levels Using an Image Intensifier and a Flat-Panel Detector-Based System  

SciTech Connect (OSTI)

Purpose: The aim of this study was to estimate radiation exposure in pediatric liver transplants recipients who underwent biliary interventional procedures and to compare radiation exposure levels between biliary interventional procedures performed using an image intensifier-based angiographic system (IIDS) and a flat panel detector-based interventional system (FPDS). Materials and Methods: We enrolled 34 consecutive pediatric liver transplant recipients with biliary strictures between January 2008 and March 2013 with a total of 170 image-guided procedures. The dose-area product (DAP) and fluoroscopy time was recorded for each procedure. The mean age was 61 months (range 4-192), and mean weight was 17 kg (range 4-41). The procedures were classified into three categories: percutaneous transhepatic cholangiography and biliary catheter placement (n = 40); cholangiography and balloon dilatation (n = 55); and cholangiography and biliary catheter change or removal (n = 75). Ninety-two procedures were performed using an IIDS. Seventy-eight procedures performed after July 2010 were performed using an FPDS. The difference in DAP between the two angiographic systems was compared using Wilcoxon rank-sum test and a multiple linear regression model. Results: Mean DAP in the three categories was significantly greater in the group of procedures performed using the IIDS compared with those performed using the FPDS. Statistical analysis showed a p value = 0.001 for the PTBD group, p = 0.0002 for the cholangiogram and balloon dilatation group, and p = 0.00001 for the group with cholangiogram and biliary catheter change or removal. Conclusion: In our selected cohort of patients, the use of an FPDS decreases radiation exposure.

Miraglia, Roberto, E-mail: rmiraglia@ismett.edu; Maruzzelli, Luigi [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Department of Diagnostic and Interventional Radiology (Italy)] [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Department of Diagnostic and Interventional Radiology (Italy); Tuzzolino, Fabio [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Department of Information Technology (Italy)] [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Department of Information Technology (Italy); Indovina, Pietro Luigi [Medical Physic ISMETT Consultant, Fismeco (Italy)] [Medical Physic ISMETT Consultant, Fismeco (Italy); Luca, Angelo [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Department of Diagnostic and Interventional Radiology (Italy)] [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Department of Diagnostic and Interventional Radiology (Italy)

2013-12-15T23:59:59.000Z

106

Energy levels, oscillator strengths, radiative decay rates, and fine-structure collision strengths for the Zn-like ions Nb XII and Mo XIII  

SciTech Connect (OSTI)

Energy levels, line strengths, oscillator strengths, radiative decay rates, and fine-structure collision strengths are presented for the Zn-like ions Nb XII and Mo XIII. The atomic data are calculated with the AUTOSTRUCTURE code, where relativistic corrections are introduced according to the Breit–Pauli distorted wave approach. We present the calculations of atomic data for 110 fine-structure levels generated from fifteen configurations (1s{sup 2}2s{sup 2}2p{sup 6}3s{sup 2}3p{sup 6}3d{sup 10})4s{sup 2}, 4s4p, 4p{sup 2}, 4s4d, 4s4f, 4s5s, 4p4d, 4s5p, 4s5d, 4p4f, 4p5s, 4d{sup 2}, 4d4f, 4f{sup 2}, and 3d{sup 9}4s{sup 2}4p. Fine-structure collision strengths for transitions from the ground and the first four excited levels are presented at six electron energies (20, 50, 80, 110, 150, and 180 Ryd). Our atomic structure data are compared with the available experimental and theoretical results.

Liang, Liang, E-mail: liangll501@163.com; Liu, Xu-yang; Zhou, Chao

2014-07-15T23:59:59.000Z

107

EBSD Images Theoretical Background  

E-Print Network [OSTI]

Motivation EBSD Images Theoretical Background Defects in the Weld Grain Growth Low Speed Welding High Speed Welding Conclusion Heat-Affected Zone Observations Welding Experiments The low density in the transportation industries. Reproducibility and the low cost make welding a major large scale assembly process

Candea, George

108

David Smith Academic background  

E-Print Network [OSTI]

David Smith Academic background Ph.D. in Mathematics (Algebra), Université de Sherbrooke, Canada project program (I. Assem, F. Bergeron, C. Reutenauer, D. Smith) $132,000 ($44,000 per year for 3 years. Schiffler and D. Smith, Friezes, strings and cluster variables, to appear in Glasgow Mathematcal Journal. 2

109

Radiation Impact of Very Low Level Radioactive Steel Reused in Building Industry with Emphasis on External Exposure Pathway - 12569  

SciTech Connect (OSTI)

Considerable quantities of various materials are accumulated during the decommissioning process of nuclear installations. Some of arising materials are activated or contaminated. However, many of them continue to have an economic value and exist in a form that can be recycled or reused for special purposes. Furthermore much of the material generated during decommissioning process will contain only small amounts of radionuclides. For these materials there exist environmental and economic incentives to maximize the use of the concept of clearance from further regulatory control. This impact analysis is devoted to mentioned incentives. The aim is to conditionally clear maximum amount of the scrap steel and consequently recycle and reuse it in form of reinforcing components in tunnel and bridge building scenarios. Recent calculations relevant for external exposure pathway indicate that concept of conditional clearance represent a feasible option for the management of radioactive materials. Even in chosen specific industrial applications it is possible to justify new, approximately one order of magnitude higher, clearance levels. However analysis of other possible exposure pathways relevant for particular scenario of reuse of conditionally cleared materials has to be performed in order to confirm indications from partially obtained results. Basically, the concept of conditional clearance can bring two basic benefits. Firstly it is saving of considerable funds, which would be otherwise used for treatment, conditioning and disposal of materials at appropriate radioactive waste repository. Moreover materials with intrinsic value (particularly metals) can be recycled and reused in industrial applications instead of investing resources on mining and production process in order to obtain new, 'fresh' materials. (authors)

Panik, Michal; Hrncir, Tomas; Necas, Vladimir [Slovak University of Technology in Bratislava, Bratislava (Slovakia)

2012-07-01T23:59:59.000Z

110

ARM - Methane Background Information  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC : XDCResearchWarmingMethane Background Information Outreach Home Room News

111

Superluminal Velocity of Photons in a Gravitational Background  

E-Print Network [OSTI]

The influence of radiative corrections on the photon propagation in a gravitational background is investigated without the low-frequency approximation $\\omega \\ll m$. The conclusion is made in this way that the velocity of light can exceed unity.

I. B. Khriplovich

1994-11-20T23:59:59.000Z

112

Radioactivity in man: levels, effects and unknowns  

SciTech Connect (OSTI)

The report discusses the potential for significant human exposure to internal radiation. Sources of radiation considered include background radiation, fallout, reactor accidents, radioactive waste, and occupational exposure to various radioisotopes. (ACR)

Rundo, J.

1980-01-01T23:59:59.000Z

113

LTS Background - Hanford Site  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickrinformationPostdocs space control News & EventsModelingBackground

114

II. HISTORICAL BACKGROUND Since 1977 the University of Oregon Solar  

E-Print Network [OSTI]

2 II. HISTORICAL BACKGROUND Since 1977 the University of Oregon Solar Monitoring Laboratory has operated a solar radiation monitoring network in the Pacific Northwest. The number of stations participat of utilities headed by the Eugene Water and Electric Board initiated the Re- gional Solar Radiation Monitoring

Oregon, University of

115

Low background counting techniques at SNOLAB  

SciTech Connect (OSTI)

Many of the experiments currently searching for dark matter, studying properties of neutrinos or searching for neutrinoless double beta decay require very low levels of radioactive backgrounds both in their own construction materials and in the surrounding environment. These low background levels are required so that the experiments can achieve the required sensitivities for their searches. SNOLAB has several facilities which are used to directly measure these radioactive backgrounds. This proceedings will describe SNOLAB's High Purity Germanium Detectors, one of which has been in continuous use for the past seven years measuring materials for many experiments in operation or under construction at SNOLAB. A description of the characterisation of SNOLAB's new germanium well detector will be presented. In addition, brief descriptions of SNOLAB's alpha-beta and electrostatic counters will be presented and a description of SNOLAB's future low background counting laboratory will be given.

Lawson, Ian; Cleveland, Bruce [SNOLAB, 1039 Regional Rd 24, Lively, ON P3Y 1N2 (Canada)] [SNOLAB, 1039 Regional Rd 24, Lively, ON P3Y 1N2 (Canada)

2013-08-08T23:59:59.000Z

116

High redshift AGNs and HI reionisation: limits from the unresolved X-ray background  

E-Print Network [OSTI]

The rapidly declining population of bright quasars at z~3 appears to make an increasingly small contribution to the ionising background at the HI Lyman limit. It is then generally though that massive stars in (pre-)galactic systems may provide the additional ionising flux needed to complete HI reionisation by z>6. A galaxy dominated background, however, may require that the escape fraction of Lyman continuum radiation from high redshift galaxies is as high as 10%, a value somewhat at odds with (admittedly scarce) observational constraints. High escape fractions from dwarf galaxies have been advocated, or, alternatively, a so-far undetected (or barely detected) population of unobscured, high-redshift faint AGNs. Here we question the latter hypothesis, and show that such sources, to be consistent with the measured level of the unresolved X-ray background at z=0, can provide a fraction of the HII filling factor not larger than 13% by z=6. The fraction rises to 10%.

Haardt, Francesco

2015-01-01T23:59:59.000Z

117

Cosmic Microwave Background Polarization  

E-Print Network [OSTI]

Cosmic microwave background (CMB) anisotropy is our richest source of cosmological information; the standard cosmological model was largely established thanks to study of the temperature anisotropies. By the end of the decade, the Planck satellite will close this important chapter and move us deeper into the new frontier of polarization measurements. Numerous ground--based and balloon--borne experiments are already forging into this new territory. Besides providing new and independent information on the primordial density perturbations and cosmological parameters, polarization measurements offer the potential to detect primordial gravity waves, constrain dark energy and measure the neutrino mass scale. A vigorous experimental program is underway worldwide and heading towards a new satellite mission dedicated to CMB polarization.

James G. Bartlett

2006-04-18T23:59:59.000Z

118

Cosmological origin of anomalous radio background  

SciTech Connect (OSTI)

The ARCADE 2 collaboration has reported a significant excess in the isotropic radio background, whose homogeneity cannot be reconciled with clustered sources. This suggests a cosmological origin prior to structure formation. We investigate several potential mechanisms and show that injection of relativistic electrons through late decays of a metastable particle can give rise to the observed excess radio spectrum through synchrotron emission. However, constraints from the cosmic microwave background (CMB) anisotropy, on injection of charged particles and on the primordial magnetic field, present a challenge. The simplest scenario is with a ?>9 GeV particle decaying into e{sup +}e{sup ?} at a redshift of z ? 5, in a magnetic field of ? 5?G, which exceeds the CMB B-field constraints, unless the field was generated after decoupling. Decays into exotic millicharged particles can alleviate this tension, if they emit synchroton radiation in conjunction with a sufficiently large background magnetic field of a dark U(1)' gauge field.

Cline, James M. [Department of Physics, McGill University, 3600 Rue University, Montréal, Québec, H3A 2T8 Canada (Canada); Vincent, Aaron C., E-mail: jcline@physics.mcgill.ca, E-mail: vincent@ific.uv.es [Instituto de Física Corpuscular, Universitat de València - CSIC, 46071, Valencia (Spain)

2013-02-01T23:59:59.000Z

119

Radiation detection method and system using the sequential probability ratio test  

DOE Patents [OSTI]

A method and system using the Sequential Probability Ratio Test to enhance the detection of an elevated level of radiation, by determining whether a set of observations are consistent with a specified model within a given bounds of statistical significance. In particular, the SPRT is used in the present invention to maximize the range of detection, by providing processing mechanisms for estimating the dynamic background radiation, adjusting the models to reflect the amount of background knowledge at the current point in time, analyzing the current sample using the models to determine statistical significance, and determining when the sample has returned to the expected background conditions.

Nelson, Karl E. (Livermore, CA); Valentine, John D. (Redwood City, CA); Beauchamp, Brock R. (San Ramon, CA)

2007-07-17T23:59:59.000Z

120

Sources of the Radio Background Considered  

SciTech Connect (OSTI)

We investigate possible origins of the extragalactic radio background reported by the ARCADE 2 collaboration. The surface brightness of the background is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low surface brightness regions of radio sources, and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, we conclude that most of the radio background is produced by radio point sources that dominate at sub {mu}Jy fluxes. We show that a truly diffuse background produced by elections far from galaxies is ruled out because such energetic electrons would overproduce the observed X-ray/{gamma}-ray background through inverse Compton scattering of the other photon fields. Unrecognized flux from low surface brightness regions of extended radio sources, or moderate flux sources missed entirely by radio source count surveys, cannot explain the bulk of the observed background, but may contribute as much as 10%. We consider both radio supernovae and radio quiet quasars as candidate sources for the background, and show that both fail to produce it at the observed level because of insufficient number of objects and total flux, although radio quiet quasars contribute at the level of at least a few percent. We conclude that the most important population for production of the background is likely ordinary starforming galaxies above redshift 1 characterized by an evolving radio far-infrared correlation, which increases toward the radio loud with redshift.

Singal, J.; /KIPAC, Menlo Park /Stanford U.; Stawarz, L.; /KIPAC, Menlo Park /Stanford U. /Jagiellonian U., Astron. Observ.; Lawrence, A.; /Edinburgh U., Inst. Astron. /KIPAC, Menlo Park /Stanford U.; Petrosian, V.; /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept.

2011-08-22T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

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.

122

Possible generation of $?$-ray laser by electrons wiggling in a background laser  

E-Print Network [OSTI]

The possibility of $\\gamma-$ray laser generation by the radiation of wiggling electrons in an usual background laser is discussed.

Qi-Ren Zhang

2014-08-13T23:59:59.000Z

123

Perturbations of supertube in KK monopole background  

E-Print Network [OSTI]

We study perturbations of supertube in KK monopole background, at both DBI and supergravity levels. We analyse both NS1-P as well as D0-F1 duality frames and study different profiles. This illuminates certain aspects of bound states of KK monopoles with supertubes.

Yogesh K. Srivastava

2006-11-29T23:59:59.000Z

124

Environmental radiation data report 80, October-December 1994. Final report  

SciTech Connect (OSTI)

Environmental Radiation Data (ERD) contains data from the Environmental Radiation Ambient Monitoring System (ERAMS). Sampling locations are selected to provide optimal population coverage while functioning to monitor fallout from nuclear devices and other forms of radioactive contamination of the environment. The radiation analyses performed on these samples include gross alpha and gross beta levels, gamma analyses for fission products, and specific analyses for uranium, plutonium, stronthium, iodine, radium, and tritium. This monitoring effort also provides ancillary information on natural background levels and on routine and accidental releases into the environment from stationary sources.

NONE

1997-02-01T23:59:59.000Z

125

Environmental radiation data report 79, July-September 1994. Final report  

SciTech Connect (OSTI)

Environmental Radiation Data (ERD) contains data from the Environmental Radiation Ambient Monitoring System (ERAMS). Sampling locations are selected to provide optimal population coverage while functioning to monitor fallout from nuclear devices and other forms of radioactive contamination of the environment. The radiation analyses performed on these samples include gross alpha and gross beta levels, gamma analyses for fission products, and specific analyses for uranium, plutonium, stronthium, iodine, radium, and tritium. This monitoring effort also provides ancillary information on natural background levels and on routine and accidental releases into the environment from stationary sources.

NONE

1997-02-01T23:59:59.000Z

126

Environmental radiation data report 81, January-March 1995. Final report  

SciTech Connect (OSTI)

Environmental Radiation Data (ERD) contains data from the Environmental Radiation Ambient Monitoring System (ERAMS). Sampling locations are selected to provide optimal population coverage while functioning to monitor fallout from nuclear devices and other forms of radioactive contamination of the environment. The radiation analyses performed on these samples include gross alpha and gross beta levels, gamma analyses for fission products, and specific analyses for uranium, plutonium, stronthium, iodine, radium, and tritium. This monitoring effort also provides ancillary information on natural background levels and on routine and accidental releases into the environment from stationary sources.

NONE

1997-02-01T23:59:59.000Z

127

Environmental radiation data report 82, April-June 1995. Final report  

SciTech Connect (OSTI)

Environmental Radiation Data (ERD) contains data from the Environmental Radiation Ambient Monitoring System (ERAMS). Sampling locations are selected to provide optimal population coverage while functioning to monitor fallout from nuclear devices and other forms of radioactive contamination of the environment. The radiation analyses performed on these samples include gross alpha and gross beta levels, gamma analyses for fission products, and specific analyses for uranium, plutonium, stronthium, iodine, radium, and tritium. This monitoring effort also provides ancillary information on natural background levels and on routine and accidental releases into the environment from stationary sources.

NONE

1997-02-01T23:59:59.000Z

128

Hanford Site background: Part 1, Soil background for nonradioactive analytes. Revision 1, Volume 1  

SciTech Connect (OSTI)

The determination of soil background is one of the most important activities supporting environmental restoration and waste management on the Hanford Site. Background compositions serve as the basis for identifying soil contamination, and also as a baseline in risk assessment processes used to determine soil cleanup and treatment levels. These uses of soil background require an understanding of the extent to which analytes of concern occur naturally in the soils. This report documents the results of sampling and analysis activities designed to characterize the composition of soil background at the Hanford Site, and to evaluate the feasibility for use as Sitewide background. The compositions of naturally occurring soils in the vadose Zone have been-determined for-nonradioactive inorganic and organic analytes and related physical properties. These results confirm that a Sitewide approach to the characterization of soil background is technically sound and is a viable alternative to the determination and use of numerous local or area backgrounds that yield inconsistent definitions of contamination. Sitewide soil background consists of several types of data and is appropriate for use in identifying contamination in all soils in the vadose zone on the Hanford Site. The natural concentrations of nearly every inorganic analyte extend to levels that exceed calculated health-based cleanup limits. The levels of most inorganic analytes, however, are well below these health-based limits. The highest measured background concentrations occur in three volumetrically minor soil types, the most important of which are topsoils adjacent to the Columbia River that are rich in organic carbon. No organic analyte levels above detection were found in any of the soil samples.

Not Available

1993-04-01T23:59:59.000Z

129

Influence of Extraterrestrial Radiation on Radiation Portal Monitors  

SciTech Connect (OSTI)

Cosmic radiation and solar flares can be a major source of background radiation at the Earth’s surface. This paper examines the relationship between extraterrestrial radiation and the detectable background in radiation portal monitors used for homeland security applications. Background radiation data from 13 radiation portal monitor facilities are examined and compared against external sources of data related to extraterrestrial radiation, including measurements at neutron monitors located at 53 cosmic-ray observatories around the Earth, four polar orbiting satellites, three geostationary satellites, ground-based geomagnetic field data from observatories around the Earth, a solar magnetic index, solar radio flux data, and sunspot activity data. Four-years (January 2003 through December 2006) of data are used in this study, which include the latter part of Solar Cycle 23 as solar activity was on the decline. The analysis shows a significant relationship between some extraterrestrial radiation and the background detected in the radiation portal monitors. A demonstrable decline is shown in the average gamma ray and neutron background at the radiation portal monitors as solar activity declined over the period of the study.

Keller, Paul E.; Kouzes, Richard T.

2009-06-01T23:59:59.000Z

130

Physical Layer Characteristics and Techniques for Visible Light Communications  

E-Print Network [OSTI]

di?erent background solar radiation levels. . . 130 xii ListBackground solar radiation characterization . . . . . . . .erent background solar radiation levels. . . . . . . . . .

Cui, Kaiyun

2012-01-01T23:59:59.000Z

131

Standards for Protection Against Radiation (Michigan)  

Broader source: Energy.gov [DOE]

This rule establishes standards for protection against radiation hazards. In addition to complying with requirements set forth, every reasonable effort should be made to maintain radiation levels...

132

Performance Evaluation of Reverberant Chamber Background Noise Levels  

E-Print Network [OSTI]

?to?simplify?the?huge?range?of?products.?All ?products?shall?be?rated?in?accordance? with?the?HVI?rating?system.?According?to?this,?all? devices?with?loudness?up?to?0.3?sones? shall?be?rated?as??below?0.3?sones?.?All?devices?fr om?0.4?sones?up?to?1.5?sones?shall?be? rounded? to? the? nearest? 0...

Ravi, Sankaranarayana

2012-02-14T23:59:59.000Z

133

Analysis of alpha backgrounds in the DEAP-1 detector  

E-Print Network [OSTI]

DEAP-1 is a 7 kg liquid argon dark matter detector used to prototype the tonne scale DEAP-3600 detector at SNOLAB.We present an analysis of the alpha particle backgrounds in DEAP-1 and isolate the radiations from various 222Rn daughters at various locations within the detector. The backgrounds will be removed by event position reconstruction and strict controls of material purity.

Kevin S. Olsen

2009-06-01T23:59:59.000Z

134

ESnet supports Sandia and APNIC IPv6 Background Radiation research  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct:DirectivesSAND2015-21271MostMirrorESnet's OSCARS

135

Background  

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

This concern is based on PTPC's interpretation of section 3.2 of BPA's Regional Dialogue Load Following Power Sales Agreement (Power Sales Agreement) template: 3.2 Take or Pay...

136

Background  

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

maintenance personnel, and film crews use small, portable lighting systems known as "mobile lighting." Traditionally, mobile lighting units are powered by diesel fuel generators...

137

Background  

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

and the Bureau of Reclamation signed 10-year agreements - known as the Columbia Basin Fish Accords - with four Northwest tribes and two states on May 2, 2008. These historic...

138

Background:  

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

files in future will now work correctly with that setting. (back to TOC) Importing the SSL Certificate in MSIE7 on Windows Vista Connecting to a Secure Socket Layer (SSL) enabled...

139

Background  

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

solutions in the area to meet its space needs and increase employee efficiency and productivity For the past 10 years, BPA has provided work space for area employees through a...

140

Background  

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

operations through another supplier if BPA was unable to supply Alcoa's Intalco smelter. In such circumstances, the demand shift would not materialize because the Intalco...

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Background  

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

Administration, January 14, 2011 Figure 2 - Natural Gas Rig Count U.S. Natural Gas Rotary Rigs in Operation (Count) 0 400 800 1200 1600 2000 J a n - 0 7 M a r - 0 7 M a y -...

142

Background  

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

V. RESPONSE TO COMMENTS: SPECIFIC CONTRACT ISSUES ... 14 a. Whether the ten year term of the Agreement is reasonable and consistent with sound business...

143

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P T E M0

144

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P T E M0Tech

145

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P T E

146

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P T

147

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P TBPA, the

148

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P TBPA,

149

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P

150

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE P

151

Background  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program CumulusAMarch-6,-2015BSCmemo.pdfDECEMBERE PAGENCY

152

Background  

Office of Scientific and Technical Information (OSTI)

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinan antagonist Journal Article: Crystal structureComposite JC-118794ArgonneAnalysing the EffectEnergy Star

153

Background:  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone6 M. Babzien, I. Ben-Zvi, P. Study ofJ U LY 2 9

154

Background  

Office of Legacy Management (LM)

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofof EnergyYou$0.C. 20545 OCTTO:March_

155

Background  

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

Renewable energy sources are critical to the nation's future, and hydrogen-powered fuel cells offer an attractive alternative to current technologies. However, fuel cell...

156

Radiation Safety Edward O'Connell  

E-Print Network [OSTI]

tissues) #12;Sources of Background Radiation Exposure · Naturally occurring radioactive materialsRadiation Safety Edward O'Connell Radiation Safety Officer Stony Brook University New York #12;STONY BROOK UNIVERSITY & U. HOSPITAL MEDICAL CENTER #12;Why Radiation Safety · Working with radioactive

157

Aluminum as a source of background in low background experiments  

E-Print Network [OSTI]

Neutrinoless double beta decay would be a key to understanding the nature of neutrino masses. The next generation of High Purity Germanium experiments will have to be operated with a background rate of better than 10^-5 counts/(kg y keV) in the region of interest around the Q value of the decay. Therefore, so far irrelevant sources of background have to be considered. The metalization of the surface of germanium detectors is in general done with aluminum. The background from the decays of 22Na, 26Al, 226Ra and 228Th introduced by this metalization is discussed. It is shown that only a special selection of aluminum can keep these background contributions acceptable.

B. Majorovits; I. Abt; M. Laubenstein; O. Volynets

2011-05-18T23:59:59.000Z

158

Radiation-resistant microorganism  

DOE Patents [OSTI]

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.

Fliermans, Carl B.

2010-06-15T23:59:59.000Z

159

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,...

160

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

DOE Patents [OSTI]

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.

Roybal, Lyle Gene

2010-06-08T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Internal and External Radioactive Backgrounds  

E-Print Network [OSTI]

Chapter 3 Internal and External Radioactive Backgrounds New physics is often discovered by pushing energies. With the current large mixing angle-MSW oscillation parameters, Borexino expects to observe 0.35 neutrino events per day per ton from 7Be in the energy window. Because there are so few events

162

REFERENCE AND BACKGROUND CHECK PROCESS  

E-Print Network [OSTI]

REFERENCE AND BACKGROUND CHECK PROCESS Workforce Planning | 408-924-2250 classcomp process. Workforce Planning will arrange this directly with the finalist(s) once the hiring manager has provided the finalist(s) name(s) to Workforce Planning. An exception to this process is for any candidates

Su, Xiao

163

E-Print Network 3.0 - atm radiation exposure Sample Search Results  

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

O'Connell Summary: tissues) 12;Sources of Background Radiation Exposure Naturally occurring radioactive materials... . Cosmic radiation. Fall-out from nuclear weapons...

164

RADIATION MONITORING  

E-Print Network [OSTI]

of Monitoring for Radiation Protection of Workers" in ICRPNo. 9, in "Advances in Radiation Protection and Dosimetry inDosimetry f o r Stray Radiation Monitoring on the CERN S i t

Thomas, R.H.

2010-01-01T23:59:59.000Z

165

Overcoming High Energy Backgrounds at Pulsed Spallation Sources  

E-Print Network [OSTI]

Instrument backgrounds at neutron scattering facilities directly affect the quality and the efficiency of the scientific measurements that users perform. Part of the background at pulsed spallation neutron sources is caused by, and time-correlated with, the emission of high energy particles when the proton beam strikes the spallation target. This prompt pulse ultimately produces a signal, which can be highly problematic for a subset of instruments and measurements due to the time-correlated properties, and different to that from reactor sources. Measurements of this background have been made at both SNS (ORNL, Oak Ridge, TN, USA) and SINQ (PSI, Villigen, Switzerland). The background levels were generally found to be low compared to natural background. However, very low intensities of high-energy particles have been found to be detrimental to instrument performance in some conditions. Given that instrument performance is typically characterised by S/N, improvements in backgrounds can both improve instrument pe...

Cherkashyna, Nataliia; DiJulio, Douglas D; Khaplanov, Anton; Pfeiffer, Dorothea; Scherzinger, Julius; Cooper-Jensen, Carsten P; Fissum, Kevin G; Ansell, Stuart; Iverson, Erik B; Ehlers, Georg; Gallmeier, Franz X; Panzner, Tobias; Rantsiou, Emmanouela; Kanaki, Kalliopi; Filges, Uwe; Kittelmann, Thomas; Extegarai, Maddi; Santoro, Valentina; Kirstein, Oliver; Bentley, Phillip M

2015-01-01T23:59:59.000Z

166

Genetic Background Modulates Gene Expression Profile Induced by Skin Irradiation in Ptch1 Mice  

SciTech Connect (OSTI)

Purpose: Ptch1 germ-line mutations in mice predispose to radiation-induced basal cell carcinoma of the skin, with tumor incidence modulated by the genetic background. Here, we examined the possible mechanisms underlying skin response to radiation in F1 progeny of Ptch1{sup neo67/+} mice crossed with either skin tumor-susceptible (Car-S) or -resistant (Car-R) mice and X-irradiated (3 Gy) at 2 days of age or left untreated. Methods and Materials: We conducted a gene expression profile analysis in mRNA samples extracted from the skin of irradiated or control mice, using Affymetrix whole mouse genome expression array. Confirmation of the results was done using real-time reverse-transcriptase polymerase chain reaction. Results: Analysis of the gene expression profile of normal skin of F1 mice at 4 weeks of age revealed a similar basal profile in the nonirradiated mice, but alterations in levels of 71 transcripts in irradiated Ptch1{sup neo67/+} mice of the Car-R cross and modulation of only eight genes in irradiated Ptch1{sup neo67/+} mice of the Car-S cross. Conclusions: These results indicate that neonatal irradiation causes a persistent change in the gene expression profile of the skin. The tendency of mice genetically resistant to skin tumorigenesis to show a more complex pattern of transcriptional response to radiation than do genetically susceptible mice suggests a role for this response in genetic resistance to basal cell tumorigenesis.

Galvan, Antonella; Noci, Sara [Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale Tumori, Milan (Italy); Mancuso, Mariateresa; Pazzaglia, Simonetta; Saran, Anna [ENEA Laboratories, Rome (Italy); Dragani, Tommaso A. [Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale Tumori, Milan (Italy)], E-mail: tommaso.dragani@istitutotumori.mi.it

2008-12-01T23:59:59.000Z

167

Proposed Lymph Node Staging System Using the International Consensus Guidelines for Lymph Node Levels Is Predictive for Nasopharyngeal Carcinoma Patients From Endemic Areas Treated With Intensity Modulated Radiation Therapy  

SciTech Connect (OSTI)

Purpose: To propose a lymph node (N) staging system for nasopharyngeal carcinoma (NPC) based on the International Consensus Guidelines for lymph node (LN) levels and MRI-determined nodal variables. Methods and Materials: The MRI scans and medical records of 749 NPC patients receiving intensity modulated radiation therapy with or without chemotherapy were retrospectively reviewed. The prognostic significance of nodal level, laterality, maximal axial diameter, extracapsular spread, necrosis, and Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) size criteria were analyzed. Results: Nodal level and laterality were the only independent prognostic factors for distant failure and disease failure in multivariate analysis. Compared with unilateral levels Ib, II, III, and/or Va involvement (hazard ratio [HR] 1), retropharyngeal lymph node involvement alone had a similar prognostic value (HR 0.71; 95% confidence interval [CI] 0.43-1.17; P=.17), whereas bilateral levels Ib, II, III, and/or Va involvement (HR 1.65; 95% CI 1.06-2.58; P=.03) and levels IV, Vb, and/or supraclavicular fossa involvement (HR 3.47; 95% CI 1.92-6.29; P<.01) both significantly increased the HR for distant failure. Thus we propose that the N category criteria could be revised as follows: N0, no regional LN metastasis; N1, retropharyngeal lymph node involvement, and/or unilateral levels Ib, II, III, and/or Va involvement; N2, bilateral levels Ib, II, III, and/or Va involvement; N3, levels IV, Vb, and/or supraclavicular fossa involvement. Compared with the 7th edition of the UICC/AJCC criteria, the proposed N staging system provides a more satisfactory distinction between the HRs for regional failure, distant failure, and disease failure in each N category. Conclusions: The proposed N staging system defined by the International Consensus Guidelines and laterality is predictive and practical. However, because of no measurements of the maximal nodal diameter on MRI slices, the prognostic significance of LN size needs further evaluation.

Li, Wen-Fei; Sun, Ying; Mao, Yan-Ping; Chen, Lei; Chen, Yuan-Yuan; Chen, Mo [Department of Radiation Oncology, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China)] [Department of Radiation Oncology, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China); Liu, Li-Zhi [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China)] [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China); Lin, Ai-Hua [Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou (China)] [Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou (China); Li, Li [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China)] [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China); Ma, Jun, E-mail: majun2@mail.sysu.edu.cn [Department of Radiation Oncology, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China)] [Department of Radiation Oncology, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou (China)

2013-06-01T23:59:59.000Z

168

BEDES Background | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Year in Review: Top Five EERE BlogAttachmentFlash2011-21 AuditInsulatedEnergyBackground BEDES

169

E-Print Network 3.0 - accidental radiation evaluation Sample...  

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

environmental contamination from decommissioning of the Summary: from the naturally occurring background radiation - both for routine releases and accidental releases......

170

E-Print Network 3.0 - arrbod acute radiation Sample Search Results  

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

... 5 Summary: to years). Exposure to naturally occurring background radiation is an example of chronic exposure. Acute......

171

E-Print Network 3.0 - acute radiation syndrones Sample Search...  

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

... 5 Summary: to years). Exposure to naturally occurring background radiation is an example of chronic exposure. Acute......

172

E-Print Network 3.0 - acute radiation effects Sample Search Results  

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

... 5 Summary: to years). Exposure to naturally occurring background radiation is an example of chronic exposure. Acute......

173

Defense-in-Depth, How Department of Energy Implements Radiation...  

Broader source: Energy.gov (indexed) [DOE]

Defense-in-Depth, How Department of Energy Implements Radiation Protection in Low Level Waste Disposal Defense-in-Depth, How Department of Energy Implements Radiation Protection in...

174

Gauging the cosmic microwave background  

E-Print Network [OSTI]

We provide a new derivation of the anisotropies of the cosmic microwave background (CMB), and find an exact expression that can be readily expanded perturbatively. Close attention is paid to gauge issues, with the motivation to examine the effect of super-Hubble modes on the CMB. We calculate a transfer function that encodes the behaviour of the dipole, and examine its long-wavelength behaviour. We show that contributions to the dipole from adiabatic super-Hubble modes are strongly suppressed, even in the presence of a cosmological constant, contrary to claims in the literature. We also introduce a naturally defined CMB monopole, which exhibits closely analogous long-wavelength behaviour. We discuss the geometrical origin of this super-Hubble suppression, pointing out that it is a simple reflection of adiabaticity, and hence argue that it will occur regardless of the matter content.

J. P. Zibin; Douglas Scott

2008-12-21T23:59:59.000Z

175

Low background aspects of GERDA  

SciTech Connect (OSTI)

The GERDA experiment operates bare Germanium diodes enriched in {sup 76}Ge in an environment of pure liquid argon to search for neutrinoless double beta decay. A very low radioactive background is essential for the success of the experiment. We present here the research done in order to remove radio-impurities coming from the liquid argon, the stainless steel cryostat and the front-end electronics. We found that liquid argon can be purified efficiently from {sup 222}Rn. The main source of {sup 222}Rn in GERDA is the cryostat which emanates about 55 mBq. A thin copper shroud in the center of the cryostat was implemented to prevent radon from approaching the diodes. Gamma ray screening of radio-pure components for front-end electronics resulted in the development of a pre-amplifier with a total activity of less than 1 mBq {sup 228}Th.

Simgen, Hardy [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

2011-04-27T23:59:59.000Z

176

Miniaturized radiation chirper  

DOE Patents [OSTI]

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.

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

1980-01-01T23:59:59.000Z

177

RPV stops bump off the background  

E-Print Network [OSTI]

We study the 8 TeV LHC reach on pair produced heavy flavored di-jet resonances. Motivated by theories of R-parity violation in supersymmetry we concentrate on a final state with two b-jets and two light jets. We exploit b-tagging to reject the background and discuss its importance at the trigger level to probe light stops. We present kinematical selections that can be used to isolate the signal as a bump in the mass distribution of the candidate resonances. We find that stops with R-parity violating couplings giving rise to fully hadronic final states can be observed in the current run of the LHC. Remarkably, the LHC can probe stop masses well within the range predicted by naturalness.

Roberto Franceschini; Riccardo Torre

2014-09-24T23:59:59.000Z

178

UTILIZATION OF PHOSWICH DETECTORS FOR SIMULTANEOUS, MULTIPLE RADIATION DETECTION  

SciTech Connect (OSTI)

A phoswich radiation detector is comprised of a phosphor sandwich in which several different phosphors are viewed by a common photomultiplier. By selecting the appropriate phosphors, this system can be used to simultaneously measure multiple radiation types (alpha, beta, gamma and/or neutron) with a single detector. Differentiation between the signals from the different phosphors is accomplished using digital pulse shape discrimination techniques. This method has been shown to result in accurate discrimination with highly reliable and versatile digital systems. This system also requires minimal component count (i.e. only the detector and a computer for signal processing). A variety of detectors of this type have been built and tested including: (1) a triple phoswich system for alpha/beta/gamma swipe counting, (2) two well-type detectors for measuring low levels of low energy photons in the presence of a high energy background, (3) a large area detector for measuring beta contamination in the presence of a photon background, (4) another large area detector for measuring low energy photons from radioactive elements such as uranium in the presence of a photon background. An annular geometry, triple phoswich system optimized for measuring alpha/beta/gamma radiation in liquid waste processing streams is currently being designed.

William H. Miller; Manuel Diaz de Leon

2003-04-15T23:59:59.000Z

179

Vehicle Radiation Monitoring Systems for Medical Waste Disposal - 12102  

SciTech Connect (OSTI)

Hospitals often declare their waste as being 'non-radioactive'; however this material often has excessive levels of radiation caused either by an accident or lack of control. To ensure the best possible protection against the accidental receipt of radioactive materials and as a safety precaution for their employees, waste-handling companies have installed large-scale radiation portal monitors at their weigh scales or entry gates of the incinerator plant, waste transfer station, and/or landfill. Large-volume plastic scintillator-based systems can be used to monitor radiation levels at entry points to companies handling medical waste. The recent and intensive field tests together with the thousands of accumulated hours of actual real-life vehicle scanning have proven that the plastic scintillation based system is an appropriate radiation control instrument for waste management companies. The Real-Time background compensation algorithm is flexible with automatic adjustable coefficients that will response to rapidly changing environmental and weather conditions maintaining the preset alarm threshold levels. The Dose Rate correction algorithms further enhance the system's ability to meet the stringent requirements of the waste industries need for Dose Rate measurements. (authors)

Kondrashov, Vladislav S.; Steranka, Steve A. [RadComm Systems Corp., 2931 Portland Dr., Oakville, ON L6H 5S4 (Canada)

2012-07-01T23:59:59.000Z

180

Estimation of Cosmic Induced Contamination in Ultra-low Background Detector Materials  

SciTech Connect (OSTI)

Executive Summary This document presents the result of investigating a way to reliably determine cosmic induced backgrounds for ultra-low background materials. In particular, it focuses on those radioisotopes produced by the interactions with cosmic ray particles in the detector materials that act as a background for experiments looking for neutrinoless double beta decay. This investigation is motivated by the desire to determine background contributions from cosmic ray activation of the electroformed copper that is being used in the construction of the MAJORANA DEMONSTRATOR. The most important radioisotope produced in copper that contributes to the background budget is 60Co, which has the potential to deposit energy in the region of interest of this experiment. Cobalt-60 is produced via cosmic ray neutron collisions in the copper. This investigation aims to provide a method for determining whether or not the copper has been exposed to cosmic radiation beyond the threshold which the Majorana Project has established as the maximum exposure. This threshold is set by the Project as the expected contribution of this source of background to the overall background budget. One way to estimate cosmic ray neutron exposure of materials on the surface of the Earth is to relate it to the cosmic ray muon exposure. Muons are minimum-ionizing particles and the available technologies to detect muons are easier to implement than those to detect neutrons. We present the results of using a portable, ruggedized muon detector, the µ-Witness made by our research group, for determination of muon exposure of materials for the MAJORANA DEMONSTRATOR. From the muon flux measurement, this report presents a method to estimate equivalent sea-level exposure, and then infer the neutron exposure of the tracked material and thus the cosmogenic activation of the copper. This report combines measurements of the muon flux taken by the µ-Witness detector with Geant4 simulations in order to assure our understanding of the µ-Witness prototype. As a proof of concept, we present the results of using this detector with electroformed copper during its transport from Pacific Northwest National Laboratory, where the copper is grown, to the underground lab in Lead, South Dakota, where the experiment is being deployed. The development of a code to be used with the Majorana parts tracking database, designed to aid in estimating the cosmogenic activation, is also presented.

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.; Berguson, Timothy J.; Greene, Austen T.

2012-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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181

Danger radiations  

ScienceCinema (OSTI)

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.

None

2011-04-25T23:59:59.000Z

182

E-Print Network 3.0 - acoustic background noise Sample Search...  

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

NOISE LEVELS IN STUDIOS AND AUDITORIA A. JAMES Sound Research Laboratories, Saxon House... complex computer and scale modelling. The specification of a background noise...

183

NNSA to Conduct Aerial Radiation Assessment Survey over Joint...  

National Nuclear Security Administration (NNSA)

will be flying over Joint Base Andrews (JBA), Md., July 17, to measure naturally occurring background radiation. A helicopter may be seen flying at low altitudes while the...

184

Design/installation and structural integrity assessment under the Federal Facility Agreement for Bethel Valley Low-Level Waste Collection and Transfer System upgrade for Building 2026 (High Radiation Level Analytical Laboratory) and Building 2099 (Monitoring and Control Station) at Oak Ridge National Laboratory  

SciTech Connect (OSTI)

This document presents a Design/Installation and Structural Integrity Assessment for a replacement tank system for portions of the Bethel Valley Low Level Waste (LLW) System, located at the Oak Ridge Reservation, Oak Ridge, Tennessee. This issue of the assessment covers the design aspects of the replacement tank system, and certifies that the design has sufficient structural integrity and is acceptable for the storing or treating of hazardous and/or radioactive substances. The present issue identifies specific activities that must be completed during the fabrication, installation, and testing of the replacement tank system in order to provide assurance that the final installation complies with governing requirements. Portions of the LLW system are several decades old, or older, and do not comply with current environmental protection regulations. Several subsystems of the LLW system have been designated to receive a state-of-the-art replacement and refurbishment. One such subsystem serves Building 2026, the High Radiation Level Analytical Laboratory. This assessment focuses on the scope of work for the Building 2026 replacement LLW Collection and Transfer System, including the provision of a new Monitoring and Control Station (Building 2099) to receive, store, and treat (adjust pH) low level radioactive waste.

Not Available

1994-10-01T23:59:59.000Z

185

Integrated nuclear radiation detector and monitor  

SciTech Connect (OSTI)

A battery powered device which can continuously monitor and detect nuclear radiation utilizing fully integrated circuitry and which is provided with an alarm which alerts persons when the radiation level exceeds a predetermined threshold.

Biehl, B.L.; Lieberman, S.I.

1982-06-22T23:59:59.000Z

186

Cavern background measurement with the ATLAS RPC system  

E-Print Network [OSTI]

The measurement of cavern background has been carried out systematically since the beginning of LHC, as soon as the luminosity produced a detectable signal, from L = 10^28 cm^2s^1 of the early 2010 operation up to L=10^28 cm^2s^1 at the end of 2011 proton-proton run, which is just 1/3 of the nominal LHC luminosity. The reason for this is to early foresee the running condition for the detector for the nominal LHC luminosity and beyond, in view of the super-LHC upgrade. Background Montecarlo calculations have been validated against data and the background map analysis pointed out hotspots due to localized cracks in the radiation shielding. The RPCs participated to this effort since the earliest stages providing an accurate correlation between luminosity and background, a 3D background map in the barrel region and a direct measurement of the cavern activation. Moreover due to the high sensitivity and very good signal to noise ratio of the proposed method, based on the gap current, the measurement was provided in...

Aielli, G; The ATLAS collaboration

2012-01-01T23:59:59.000Z

187

Radiation Damping of Shallow Foundations on Nonlinear Soil Medium  

E-Print Network [OSTI]

to the reduction of radiation damping due to soil yielding.since the reduced radiation damping at foundation level will2007 Paper No. 1150 RADIATION DAMPING OF SHALLOW FOUNDATIONS

Zhang, Jian; Tang, Yuchuan

2007-01-01T23:59:59.000Z

188

Modeling surface backgrounds from radon progeny plate-out  

SciTech Connect (OSTI)

The next generation low-background detectors operating deep underground aim for unprecedented low levels of radioactive backgrounds. The surface deposition and subsequent implantation of radon progeny in detector materials will be a source of energetic background events. We investigate Monte Carlo and model-based simulations to understand the surface implantation profile of radon progeny. Depending on the material and region of interest of a rare event search, these partial energy depositions can be problematic. Motivated by the use of Ge crystals for the detection of neutrinoless double-beta decay, we wish to understand the detector response of surface backgrounds from radon progeny. We look at the simulation of surface decays using a validated implantation distribution based on nuclear recoils and a realistic surface texture. Results of the simulations and measured ? spectra are presented.

Perumpilly, G.; Guiseppe, V. E.; Snyder, N. [University of South Dakota, Vermillion, South Dakota 57069 (United States)] [University of South Dakota, Vermillion, South Dakota 57069 (United States)

2013-08-08T23:59:59.000Z

189

EXTRAGALACTIC VERY HIGH ENERGY GAMMA-RAY BACKGROUND  

SciTech Connect (OSTI)

We study the origin of the extragalactic diffuse gamma-ray background using the data from the Fermi telescope. To estimate the background level, we count photons at high Galactic latitudes |b| > 60 Degree-Sign . Subtracting photons associated with known sources and the residual cosmic-ray and Galactic diffuse backgrounds, we estimate the extragalactic gamma-ray background (EGB) flux. We find that the spectrum of EGB in the very high energy band above 30 GeV follows the stacked spectrum of BL Lac objects. Large Area Telescope data reveal the positive (1 + z) {sup k}, 1 < k < 4 cosmological evolution of the BL Lac source population consistent with that of their parent population, Fanaroff-Riley type I radio galaxies. We show that EGB at E > 30 GeV could be completely explained by emission from unresolved BL Lac objects if k {approx_equal} 3.

Neronov, A. [ISDC Data Center for Astrophysics, Chemin d'Ecogia 16, CH-1290 Versoix (Switzerland); Semikoz, D. V. [APC, 10 rue Alice Domon et Leonie Duquet, F-75205 Paris Cedex 13 (France)

2012-09-20T23:59:59.000Z

190

Power Systems Engineering Research Center PSERC Background Paper  

E-Print Network [OSTI]

Power Systems Engineering Research Center PSERC Background Paper Monitoring and Control of Power level control centers. However, there is little standardization of the monitoring process and data to the control center operators and security coordinators, or to the computers that can detect anomalous patterns

191

Gravitational clustering in Static and Expanding Backgrounds  

E-Print Network [OSTI]

A brief summary of several topics in the study of gravitational many body problem is given. The discussion covers both static backgrounds (applicable to astrophysical systems) as well as clustering in an expanding background (relevant for cosmology)

T. Padmanabhan

2003-08-28T23:59:59.000Z

192

Remote radiation dosimetry  

DOE Patents [OSTI]

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.

Braunlich, P.F.; Tetzlaff, W.; Hegland, J.E.; Jones, S.C.

1991-03-12T23:59:59.000Z

193

Ionizing radiation detector  

DOE Patents [OSTI]

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.

Thacker, Louis H. (Knoxville, TN)

1990-01-01T23:59:59.000Z

194

Network Requirements Workshop - Documents and Background Materials  

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

Science Requirements Reviews Network Requirements Reviews Documents and Background Materials Science Engagement Move your data Programs & Workshops Science...

195

Offsite environmental monitoring report: Radiation monitoring around United States nuclear test areas, calendar year 1991  

SciTech Connect (OSTI)

This report describes the Offsite Radiation Safety Program conducted during 1991 by the Environmental Protection Agency`s (EPA`s) Environmental Monitoring Systems Laboratory-Las Vegas. This laboratory operates an environmental radiation monitoring program in the region surrounding the Nevada Test Site (NTS) and at former test sites in Alaska, Colorado, Mississippi, Nevada, and New Mexico. The surveillance program is designed to measure levels and trends of radioactivity, if present, in the environment surrounding testing areas to ascertain whether current radiation levels and associated doses to the general public are in compliance with existing radiation protection standards. The surveillance program additionally has the responsibility to take action to protect the health and well being of the public in the event of any accidental release of radioactive contaminants. Offsite levels of radiation and radioactivity are assessed by sampling milk, water, and air; by deploying thermoluminescent dosimeters (TLDs) and using pressurized ion chambers (PICs); and by biological monitoring of animals, food crops, and humans. Personnel with mobile monitoring equipment are placed in areas downwind from the test site prior to each nuclear weapons test to implement protective actions, provide immediate radiation monitoring, and obtain environmental samples rapidly after any occurrence of radioactivity release. Comparison of the measurements and sample analysis results with background levels and with appropriate standards and regulations indicated that there was no radioactivity detected offsite by the various EPA monitoring networks and no exposure above natural background to the population living in the vicinity of the NTS that could be attributed to current NTS activities. Annual and long-term trends were evaluated in the Noble Gas, Tritium, Milk Surveillance, Biomonitoring, TLD, PIC networks, and the Long-Term Hydrological Monitoring Program.

Chaloud, D.J.; Dicey, B.B.; Mullen, A.A.; Neale, A.C.; Sparks, A.R.; Fontana, C.A.; Carroll, L.D.; Phillips, W.G.; Smith, D.D.; Thome, D.J.

1992-01-01T23:59:59.000Z

196

Offsite environmental monitoring report; radiation monitoring around United States nuclear test areas, Calendar Year 1996  

SciTech Connect (OSTI)

This report describes the Offsite Radiation Safety Program. This laboratory operated an environmental radiation monitoring program in the region surrounding the Nevada Test Site (NTS) and at former test sites in Alaska, Colorado, Mississippi, Nevada, and New Mexico. The surveillance program is designed to measure levels and trends of radioactivity, if present, in the environment surrounding testing areas to ascertain whether current radiation levels and associated doses to the general public are in compliance with existing radiation protection standards. The surveillance program additionally has the responsibility to take action to protect the health and well being of the public in the event of any accidental release of radioactive contaminants. Offsite levels of radiation and radioactivity are assessed by sampling milk, water, and air; by deploying thermoluminescent dosimeters (TLDs); and using pressurized ionization chambers (PICs). No nuclear weapons testing was conducted in 1996 due to the continuing nuclear test moratorium. During this period, R and IE personnel maintained readiness capability to provide direct monitoring support if testing were to be resumed and ascertained compliance with applicable EPA, DOE, state, and federal regulations and guidelines. Comparison of the measurements and sample analysis results with background levels and with appropriate standards and regulations indicated that there was no airborne radioactivity from diffusion or resuspension detected by the various EPA monitoring networks surrounding the NTS. There was no indication of potential migration of radioactivity to the offsite area through groundwater and no radiation exposure above natural background was received by the offsite population. All evaluated data were consistent with previous data history.

Davis, M.G.; Flotard, R.D.; Fontana, C.A.; Huff, P.A.; Maunu, H.K.; Mouck, T.L.; Mullen, A.A.; Sells, M.D.

1997-08-01T23:59:59.000Z

197

Measurement of Radiation Damage on Silica Aerogel \\v Cerenkov Radiator  

E-Print Network [OSTI]

We measured the radiation damage on silica aerogel \\v Cerenkov radiators originally developed for the $B$-factory experiment at KEK. Refractive index of the aerogel samples ranged from 1.012 to 1.028. The samples were irradiated up to 9.8~MRad of equivalent dose. Measurements of transmittance and refractive index were carried out and these samples were found to be radiation hard. Deteriorations in transparency and changes of refractive index were observed to be less than 1.3\\% and 0.001 at 90\\% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed.

S. K. Sahu et al

1996-04-11T23:59:59.000Z

198

Cellular telephone-based radiation detection instrument  

DOE Patents [OSTI]

A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

Craig, William W. (Pittsburg, CA); Labov, Simon E. (Berkeley, CA)

2011-06-14T23:59:59.000Z

199

Background reduction and sensitivity for germanium double beta decay experiments  

E-Print Network [OSTI]

Germanium detectors have very good capabilities for the investigation of rare phenomena like the neutrinoless double beta decay. Rejection of the background entangling the expected signal is one primary goal in this kind of experiments. Here, the attainable background reduction in the energy region where the neutrinoless double beta decay signal of 76Ge is expected to appear has been evaluated for experiments using germanium detectors, taking into consideration different strategies like the granularity of the detector system, the segmentation of each individual germanium detector and the application of Pulse Shape Analysis techniques to discriminate signal from background events. Detection efficiency to the signal is affected by background rejection techniques, and therefore it has been estimated for each of the background rejection scenarios considered. Finally, conditions regarding crystal mass, radiopurity, exposure to cosmic rays, shielding and rejection capabilities are discussed with the aim to achieve a background level of 10-3 c keV-1 kg-1 y-1 in the region of interest, which would allow to explore neutrino effective masses around 40 meV.

H. Gómez; S. Cebrián; J. Morales; J. A. Villar

2007-08-29T23:59:59.000Z

200

ISO and the Cosmic Infrared Background  

E-Print Network [OSTI]

ISO observed, for the first time to such a high sensitivity level, the mid- and far-infrared universe. A Number of deep surveys were performed to probe the cosmological evolution of galaxies. In this review, I discuss and summarize results of mid-infrared ISOCAM and far-infrared ISOPHOT surveys, and show how our vision of the extragalactic infrared universe has become more accurate. In particular, ISO allowed us to resolve into sources a significant fraction of the Cosmic Infrared Background (CIB) in the mid-infrared, and to probe a fainter population in the far-infrared with the detection of the CIB fluctuations. Together with other wavelength data sets, the nature of ISO galaxies is now in the process of being understood. I also show that the high quality of the ISO data put strong constraints on the scenarios of galaxy evolution. This induced a burst in the development of models, yielding to a more coherent picture of galaxy evolution. I finally emphasize the potential of the ISO data archive in the field of observational cosmology, and describe the next steps, in particular the forthcoming cosmological surveys to be carried out by SIRTF.

Herve Dole

2002-12-12T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

K-mouflage Cosmology: the Background Evolution  

E-Print Network [OSTI]

We study the cosmology of K-mouflage theories at the background level. We show that the effects of the scalar field are suppressed at high matter density in the early Universe and only play a role in the late time Universe where the deviations of the Hubble rate from its $\\Lambda$-CDM counterpart can be of the order five percent for redshifts $1 \\lesssim z \\lesssim 5$. Similarly, we find that the equation of state can cross the phantom divide in the recent past and even diverge when the effective scalar energy density goes negative and subdominant compared to matter, preserving the positivity of the squared Hubble rate. These features are present in models for which Big Bang Nucleosynthesis is not affected. We analyze the fate of K-mouflage when the nonlinear kinetic terms give rise to ghosts, particle excitations with negative energy. In this case, we find that the K-mouflage theories can only be considered as an effective description of the Universe at low energy below $1$ keV. In the safe ghost-free models, we find that the equation of state always diverges in the past and changes significantly by a few percent since $z\\lesssim 1$.

Philippe Brax; Patrick Valageas

2014-11-30T23:59:59.000Z

202

Hawking radiation in moving plasmas  

E-Print Network [OSTI]

Bi-metricity and Hawking radiation are exhibit in non-relativistic moving magnetohydrodynamics (MHD) plasma medium generating two Riemannian effective spacetimes. The first metric is a flat metric although the speed of "light" is given by a time dependent signal where no Hawking radiation or effective black holes are displayed. This metric comes from a wave equation which the scalar function comes from the scalar potential of the background velocity of the fluid and depends on the perturbation of the magnetic background field. The second metric is an effective spacetime metric which comes from the perturbation of the background MHD fluid. This Riemann metric exhibits a horizon and Hawking radiation which can be expressed in terms of the background constant magnetic field. The effective velocity is given Alfven wave velocity of plasma physics. The effective black hole found here is analogous to the optical black hole in moving dielectrics found by De Lorenci et al [Phys. Rev. D (2003)] where bi-metricity and Hawking radiation in terms of the electric field are found.

L. C. Garcia de Andrade

2005-09-07T23:59:59.000Z

203

Technical background document for soil screening guidance. Review draft  

SciTech Connect (OSTI)

The document provides the technical background behind the development of the November 1994 Soil Screening Guidance for Superfund. These documents define the Soil Screening framework, a suite of methodologies for developing Soil Screening Levels (SSLs) for 107 chemicals commonly found at Superfund sites. The document is an updated version of the background document developed in support of the September 30, 1993, draft SSL guidance (PB93-963508). The document and the Guidance is available for public comment and is currently undergoing extensive peer review. Because the guidance is still under review, it and this document should not be used until they are finalized following this rigorous technical review and public comment.

Not Available

1994-12-01T23:59:59.000Z

204

Beam-Induced Backgrounds in the CLIC Detectors  

E-Print Network [OSTI]

The beam parameters of the proposed CLIC linear electron-positron collider with a centre-of-mass energy of up to 3 TeV will lead to high rates of beam-induced background events. In this note simulation studies of ?? ? hadron interactions and of incoherent electron-positron pair production are presented. The CLIC detector concepts and their optimisation to reduce background occupancies are described. The characteristics of the events are discussed and resulting occupancies and energy deposits, as well as expected levels of both total ionising dose and displacement damage in the detectors are discussed.

Dannheim, D

2012-01-01T23:59:59.000Z

205

Enhanced radiation resistant fiber optics  

DOE Patents [OSTI]

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.

Lyons, P.B.; Looney, L.D.

1993-11-30T23:59:59.000Z

206

Radiation detector  

DOE Patents [OSTI]

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.

Fultz, Brent T. (Berkeley, CA)

1983-01-01T23:59:59.000Z

207

Radiation detector  

DOE Patents [OSTI]

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.

Fultz, B.T.

1980-12-05T23:59:59.000Z

208

Development of a New Analysis Tool for Evaluating and Correcting for Weather Conditions that Constrain Radiation Portal Monitor Performance  

SciTech Connect (OSTI)

Researchers at Oak Ridge National Laboratory (ORNL) developed the Adaptable, Multiplatform, Real-Time Analysis Package (AMRAP) for the continuous measurement of environmental radionuclide decay. AMRAP is a completely open source visualization and analysis package capable of combining a variety of data streams into an array of real-time plots. Once acquired, data streams are analyzed to store static images and extract data based on previously defined thresholds. AMRAP is currently used at ORNL to combine data streams from an Ortec Detective high-purity germanium (HPGe) detector, a TSA Systems radiation portal monitor (RPM), and an Orion weather station. The combined data are used to study the rain-induced increase in RPM background radiation levels. RPMs experience an increase in background radiation during precipitation due to the deposition of atmospheric radionuclides on the ground. Using AMRAP results in a real-time analysis workstation specifically dedicated to the study of RPM background radiation levels. By means of an editable library of common inputs, AMRAP is adaptable to remote monitoring applications that would benefit from the real-time visualization and analysis of radiation measurements. To study rain-induced increases in background radiation levels observed in radiation portal monitors (RPMs), researchers at Oak Ridge National Laboratory (ORNL) developed a software package that allows data with different formats to be analyzed and plotted in near real time. The Adaptable, Multiplatform, Real-Time Analysis Package (AMRAP) was developed to operate in the background and capture plots of important data based on previously defined thresholds. After executing AMRAP, segments of a data stream can be captured without additional post-processing. AMRAP can also display previously recorded data to facilitate a detailed offline analysis. Without access to these capabilities in a single software package, analyzing multiple continuously recorded data streams with different formats is impractical. Commercially available acquisition software packages record and analyze radiation measurements but are not designed to perform real-time analysis in conjunction with data from other vendors. The lack of collaboration between vendors is problematic when research requires different data streams to be correlated in time and immediately analyzed. AMRAP was specifically developed to provide a solution to this problem. AMRAP is a completely open source visualization and analysis package capable of plotting and analyzing data from different vendors in near real time.

Guzzardo, Tyler [ORNL] [ORNL; Livesay, Jake [ORNL] [ORNL

2011-01-01T23:59:59.000Z

209

Solar Background Document 6 | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

6.pdf More Documents & Publications Solar Background Document 5 "Large Power Transformers and the U.S. Electric Grid" Report (June 2012) Dams and Energy Sectors...

210

Final Conservation Billing Credit Policy Supplement Background...  

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

December 17, 2014 Page 1 Final Conservation Billing Credit Policy Supplement Background and Need: This Conservation Billing Credit Policy Supplement describes how Bonneville Power...

211

THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): THE LOW RESOLUTION SPECTROMETER  

SciTech Connect (OSTI)

Absolute spectrophotometric measurements of diffuse radiation at 1 {mu}m to 2 {mu}m are crucial to our understanding of the radiative content of the universe from nucleosynthesis since the epoch of reionization, the composition and structure of the zodiacal dust cloud in our solar system, and the diffuse galactic light arising from starlight scattered by interstellar dust. The Low Resolution Spectrometer (LRS) on the rocket-borne Cosmic Infrared Background Experiment is a {lambda}/{Delta}{lambda} {approx} 15-30 absolute spectrophotometer designed to make precision measurements of the absolute near-infrared sky brightness between 0.75 {mu}m <{lambda} < 2.1 {mu}m. This paper presents the optical, mechanical, and electronic design of the LRS, as well as the ground testing, characterization, and calibration measurements undertaken before flight to verify its performance. The LRS is shown to work to specifications, achieving the necessary optical and sensitivity performance. We describe our understanding and control of sources of systematic error for absolute photometry of the near-infrared extragalactic background light.

Tsumura, K.; Arai, T.; Matsumoto, T.; Matsuura, S.; Murata, K. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronoutical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J.; Bock, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Brown, S.; Lykke, K.; Smith, A. [Optical Technology Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Hristov, V.; Levenson, L. R.; Mason, P. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Keating, B.; Renbarger, T. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Sullivan, I., E-mail: tsumura@ir.isas.jaxa.jp [Department of Physics, The University of Washington, Seattle, WA 98195 (United States); and others

2013-08-15T23:59:59.000Z

212

Reducing backgrounds in the higgs factory muon collider detector  

SciTech Connect (OSTI)

A preliminary design of the 125-GeV Higgs Factory (HF) Muon Collider (MC) has identified an enormous background loads on the HF detector. This is related to the twelve times higher muon decay probability at HF compared to that previously studied for the 1.5-TeV MC. As a result of MARS15 optimization studies, it is shown that with a carefully designed protection system in the interaction region, in the machine-detector interface and inside the detector one can reduce the background rates to a manageable level similar to that achieved for the optimized 1.5-TeV case. The main characteristics of the HF detector background are presented for the configuration found.

Mokhov, N. V.; Tropin, I. S.

2014-06-01T23:59:59.000Z

213

National Ambient Radiation Database  

SciTech Connect (OSTI)

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.

Dziuban, J.; Sears, R.

2003-02-25T23:59:59.000Z

214

Radiation dosimeter  

DOE Patents [OSTI]

A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even though the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

Fox, Richard J. (Oak Ridge, TN)

1983-01-01T23:59:59.000Z

215

Radiation dosimeter  

DOE Patents [OSTI]

A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even through the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

Fox, R.J.

1981-09-01T23:59:59.000Z

216

Radiative ?(1S) decays  

E-Print Network [OSTI]

— 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...

Baringer, Philip S.

1990-03-01T23:59:59.000Z

217

RADIATION SAFETY TRAINING MANUAL Radiation Safety Office  

E-Print Network [OSTI]

RADIATION SAFETY TRAINING MANUAL Radiation Safety Office 130 DeSoto Street G-7 Parran with sources of ionizing radiation are required to be instructed in the basic principles of radiation protection and the potential risks of ionizing radiation. Radiation Safety Office personnel provide

Sibille, Etienne

218

Appendix G. Radiation Appendix G. Radiation  

E-Print Network [OSTI]

-made sources. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation of radiation and its effects on the environment and biological systems. Radiation comes from natural and humanAppendix G. Radiation #12;#12;Appendix G. Radiation This appendix presents basic facts about

Pennycook, Steve

219

Assessing exposure to radiation  

SciTech Connect (OSTI)

Since the founding of Lawrence Livermore National Laboratory, we have been world leaders in evaluating the risks associated with radiation. Ultrasensitive tools allow us not only to measure radionuclides present in the body but also to reconstruct the radiation dose from past nuclear events and to project the levels of radiation that will still be present in the body for 50 years after the initial intake. A variety of laboratory procedures, including some developed here, give us detailed information on the effects of radiation at the cellular level. Even today, we are re-evaluating the neutron dose resulting from the bombing at Hiroshima. Our dose reconstruction and projection capabilities have also been applied to studies of Nagasaki, Chernobyl, the Mayak industrial complex in the former Soviet Union, the Nevada Test Site, Bikini Atoll, and other sites. We are evaluating the information being collected on individuals currently working with radioactive material at Livermore and elsewhere as well as previously collected data on workers that extends back to the Manhattan Project.

Walter, K.

1997-01-01T23:59:59.000Z

220

Fractal Structure of Isothermal Lines and Loops on the Cosmic Microwave Background  

E-Print Network [OSTI]

Fractal Structure of Isothermal Lines and Loops on the Cosmic Microwave Background Naoki KOBAYASHI and the fractal structure is confirmed in the radiation temperature fluctuation. We estimate the fractal exponents, such as the fractal dimension De of the entire pattern of isothermal lines, the fractal dimension Dc of a single

Chiang, Lung-Yih

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Stochastic Gravitational Wave Background from Exoplanets  

E-Print Network [OSTI]

Recent exoplanet surveys have predicted a very large population of planetary systems in our galaxy, more than one planet per star on the average, perhaps totalling about two hundred billion. These surveys, based on electro-magnetic observations, are limited to a very small neighbourhood of the solar system and the estimations rely on the observations of only a few thousand planets. On the other hand, orbital motions of planets around stars are expected to emit gravitational waves (GW), which could provide information about the planets not accessible to electro-magnetic astronomy. The cumulative effect of the planets, with periods ranging from few hours to several years, is expected to create a stochastic GW background (SGWB). We compute the characteristic GW strain of this background based on the observed distribution of planet parameters. We also show that the integrated extragalactic background is comparable or less than the galactic background at different frequencies. Our estimate shows that the net backg...

Ain, Anirban; Mitra, Sanjit

2015-01-01T23:59:59.000Z

222

Background and Motivation Biomass derived syngas contains  

E-Print Network [OSTI]

Background and Motivation · Biomass derived syngas contains: CO, H2, small hydrocarbons, H2S prepared by SEA contain smaller metal particle sizes and have higher dispersion · The quantity of reducible

Das, Suman

223

Environmental Permit Application Background Statement (Delaware)  

Broader source: Energy.gov [DOE]

The purpose of Chapter 79 of Delaware Title 7 is to ensure that the State has adequate information about the background of applicants or regulated parties for the purposes of processing permits and...

224

Fractal generation of textures and backgrounds  

E-Print Network [OSTI]

FRACTAL GENERATION OF TEXTURES AND BACKGROUNDS A Thesis by KEVIN DUANE REUTER Subtnitted to the Oflice of Graduate Studies of Texas A&M University in partial fulfilhnent of the requirements for the degree of MASTER OF SCIENCE August 1999... Major Subject; Visualization Sciences FRACTAL GENERATION OF TEXTURES AND BACKGROUNDS A Thesis by KEVIN DUANE REUTER Submitted to Texas ARM University in partial fulfilhnent of the requirements for the degree of MASTER OF SCIENCE Approved...

Reuter, Kevin Duane

1999-01-01T23:59:59.000Z

225

Background Assay and Rejection in DRIFT  

E-Print Network [OSTI]

The DRIFT-IId dark matter detector is a m$^3$-scale low-pressure TPC with directional sensitivity to WIMP-induced nuclear recoils. Its primary backgrounds were due to alpha decays from contamination on the central cathode. Efforts to reduce these backgrounds led to replacing the 20 \\mu m wire central cathode with one constructed from 0.9 \\mu m aluminized mylar, which is almost totally transparent to alpha particles. Detailed modeling of the nature and origin of the remaining backgrounds led to an in-situ, ppt-sensitive assay of alpha decay backgrounds from the central cathode. This led to further improvements in the thin-film cathode resulting in over 2 orders of magnitude reduction in backgrounds compared to the wire cathode. Finally, the addition of O$_2$ to CS$_2$ gas was found to produce multiple species of electronegative charge carriers, providing a method to determine the absolute position of nuclear recoils and reject all known remaining backgrounds while retaining a high efficiency for nuclear recoil detection.

Jeff Brack; Ed Daw; Alexei Dorofeev; Anthony Ezeribe; Jean-Luc Gauvreau; Michael Gold; John Harton; Randy Lafler; Robert Lauer; Eric R. Lee; Dinesh Loomba; John Matthews; Eric H. Miller; Alissa Monte; Alex Murphy; Sean Paling; Nguyen Phan; Steve Sadler; Andrew Scarff; Daniel Snowden-Ifft; Neil Spooner; Sam Telfer; Daniel Walker; Matt Williams; Leonid Yuriev

2014-04-08T23:59:59.000Z

226

Gamma-Ray Bursts, Ultra High Energy Cosmic Rays, and Cosmic Gamma-Ray Background  

E-Print Network [OSTI]

We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs, and this large energy can be radiated in TeV range by synchrotron radiation of ultra-high-energy protons (\\sim 10^{20} eV). The possible detection of GRBs above 10 TeV suggested by the Tibet and HEGRA groups also supports this idea. If this is the case, most of TeV gamma-rays from GRBs are absorbed in intergalactic fields and eventually form GeV gamma-ray background, whose flux is in good agreement with the recent observation.

Tomonori Totani

1999-04-13T23:59:59.000Z

227

Radiation receiver  

DOE Patents [OSTI]

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.

Hunt, A.J.

1983-09-13T23:59:59.000Z

228

Radiation receiver  

DOE Patents [OSTI]

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.

Hunt, Arlon J. (Oakland, CA)

1983-01-01T23:59:59.000Z

229

Operational Strategies for Low-Level Radioactive Waste Disposal Site in Egypt - 13513  

SciTech Connect (OSTI)

The ultimate aims of treatment and conditioning is to prepare waste for disposal by ensuring that the waste will meet the waste acceptance criteria of a disposal facility. Hence the purpose of low-level waste disposal is to isolate the waste from both people and the environment. The radioactive particles in low-level waste emit the same types of radiation that everyone receives from nature. Most low-level waste fades away to natural background levels of radioactivity in months or years. Virtually all of it diminishes to natural levels in less than 300 years. In Egypt, The Hot Laboratories and Waste Management Center has been established since 1983, as a waste management facility for LLW and ILW and the disposal site licensed for preoperational in 2005. The site accepts the low level waste generated on site and off site and unwanted radioactive sealed sources with half-life less than 30 years for disposal and all types of sources for interim storage prior to the final disposal. Operational requirements at the low-level (LLRW) disposal site are listed in the National Center for Nuclear Safety and Radiation Control NCNSRC guidelines. Additional procedures are listed in the Low-Level Radioactive Waste Disposal Facility Standards Manual. The following describes the current operations at the LLRW disposal site. (authors)

Mohamed, Yasser T. [Hot Laboratories and Waste Management Center, Atomic Energy Authority, 3 Ahmed El-Zomor St., El-Zohour District, Naser City, 11787, Cairo (Egypt)] [Hot Laboratories and Waste Management Center, Atomic Energy Authority, 3 Ahmed El-Zomor St., El-Zohour District, Naser City, 11787, Cairo (Egypt)

2013-07-01T23:59:59.000Z

230

Design of a novel Cherenkov detectors system for machine induced background monitoring in the CMS cavern  

E-Print Network [OSTI]

A novel detector system has been designed for an efficient online measurement of the machineinduced background in the CMS experimental cavern. The suppression of the CMS cavern background originating from pp collision products and the 25 ns bunch spacing have set the requirements for the detector design. Each detector unit will be a radiation hard, cylindrical Cherenkov radiator optically coupled to an ultra-fast UV-sensitive photomultiplier tube, providing a prompt, directionally sensitive measurement. Simulation and test beam measurements have shown the achievability of the goals that have driven the baseline design. The system will consist of 20 azimuthally distributed detectors per end, installed at a radius of r ~ 180 cm and a distance 20.6 m away from the CMS interaction region. The detector units will enable a measurement of the transverse distribution of the bunchby- bunch machine induced background flux. This will provide important feedback from the CMS on the beam conditions during the LHC machine s...

Orfanelli, Styliani; Giunta, Marina; Stickland, David P; Ambrose, Mitchell J; Rusack, Roger; Finkel, Alexey

2013-01-01T23:59:59.000Z

231

Establishment of a Background Environmental Monitoring Station for the PNNL Campus  

SciTech Connect (OSTI)

The environmental surveillance of background levels of radionuclides and, in particular, the siting of a background environmental surveillance (monitoring) station are examined. Many published works identify and stress the need for background monitoring; however, little definitive and comprehensive information for siting a station exists. A definition of an ideal background monitoring location and the generic criteria recommended for use in establishing such a background monitoring location are proposed. There are seven primary (mandatory) criteria described with two additional, optional criteria. The criteria are applied to the Richland, Washington (WA), Pacific Northwest National Laboratory (PNNL) Campus, which currently uses background monitoring data from the nearby Hanford Site. Eleven potential background monitoring sites were identified, with one location in Benton City, WA found to meet all of the mandatory and optional criteria. It is expected that the new sampler will be installed and operating by the end of June, 2015.

Fritz, Brad G.; Snyder, Sandra F.; Barnett, J. M.; Bisping, Lynn E.; Rishel, Jeremy P.

2014-12-18T23:59:59.000Z

232

Non-thermal Cosmic Backgrounds from Blazars: the contribution to the CMB, X-ray and gamma-ray Backgrounds  

E-Print Network [OSTI]

We present a new assessment of the contribution of Blazars to the extragalactic background radiation across the e.m. spectrum. Our calculations rely on deep Blazar radio counts that we derived combining several multifrequency surveys. The integrated Blazar emission yields a broad-band non-thermal background that in some parts of the e.m. spectrum dominates the extragalactic brightness. Blazars are the main point-like contributors to the CMB. Their integrated emission causes an apparent T increase of 5-50 muK in the 50-250 GHz range. The CMB fluctuation spectrum is sensibly contaminated at l>300, for a Poissonian source distribution, or at lower l values if spatial clustering is present. We estimate that well over 100,000 Blazars will produce a significant signal in the PLANCK CMB anisotropy maps. Because of the microwave-Xray flux correlation, these sources are expected to have flux > a few 10^{-15} erg/s in the soft X-ray band. Thus, a large fraction of the foreground sources in CMB anisotropy maps could be identified and removed using a multi frequency approach, provided that a sufficiently deep all sky X-ray survey will be available. We further show that Blazars are a major constituent of all high-E extragalactic backgrounds. Their contribution is 11-12% at X-ray frequencies and possibly 100% in the 0.5-50 MeV band. At E>100 MeV, the Blazar collective emission, obtained extrapolating their integrated micro-wave flux to the gamma-ray band using the SED of EGRET detected sources, over-predicts the extragalactic background by a large factor, implying that Blazars not only dominate the gamma-ray sky but also that their average duty cycle at these frequencies must be rather low. We also find that Blazars of the HBL type may produce a significant amount of flux at TeV energies.

P. Giommi; S. Colafrancesco; E. Cavazzuti; M. Perri; C. Pittori

2005-08-01T23:59:59.000Z

233

Background-reducing X-ray multilayer mirror  

DOE Patents [OSTI]

Background-reducing x-ray multilayer mirror. A multiple-layer "wavetrap" deposited over the surface of a layered, synthetic-microstructure soft x-ray mirror optimized for reflectivity at chosen wavelengths is disclosed for reducing the reflectivity of undesired, longer wavelength incident radiation incident thereon. In three separate mirror designs employing an alternating molybdenum and silicon layered, mirrored structure overlaid by two layers of a molybdenum/silicon pair anti-reflection coating, reflectivities of near normal incidence 133, 171, and 186 .ANG. wavelengths have been optimized, while that at 304 .ANG. has been minimized. The optimization process involves the choice of materials, the composition of the layer/pairs as well as the number thereof, and the distance therebetween for the mirror, and the simultaneous choice of materials, the composition of the layer/pairs, and their number and distance for the "wavetrap."

Bloch, Jeffrey J. (Los Alamos, NM); Roussel-Dupre', Diane (Los Alamos, NM); Smith, Barham W. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

234

Low-background tracker development for SuperNEMO  

SciTech Connect (OSTI)

The SuperNEMO experiment will search for neutrinoless double beta decay (0???) with a target sensitivity of T{sub 1/2}(0?) > 10{sup 26} years, corresponding to an effective neutrino mass of 50-100 meV. At its heart there is a low-background gaseous tracking detector which allows for extremely efficient background rejection and, if 0??? is observed, may provide important insights into the mechanism via which it may be mediated. Radon inside the tracker, which can mimic rare ?? events, is one of the most dangerous backgrounds for SuperNEMO. To reach the target sensitivity the radon concentration inside the tracking volume must be < 0.15 mBq/m{sup 3}. To reach this challengingly-low level of radon, a considerable program of R and D has been undertaken. This includes automation of the tracker-wiring process, development of a dedicated setup to measure radon diffusion and a 'radon concentration line' which will be able to measure levels of radon in the ?Bq/m{sup 3} range.

Mott, James [University College London, London, WC1E 6BT (United Kingdom)] [University College London, London, WC1E 6BT (United Kingdom); Collaboration: SuperNEMO Collaboration; and others

2013-08-08T23:59:59.000Z

235

A COSMIC MICROWAVE BACKGROUND LENSING MASS MAP AND ITS CORRELATION WITH THE COSMIC INFRARED BACKGROUND  

SciTech Connect (OSTI)

We use a temperature map of the cosmic microwave background (CMB) obtained using the South Pole Telescope at 150 GHz to construct a map of the gravitational convergence to z {approx} 1100, revealing the fluctuations in the projected mass density. This map shows individual features that are significant at the {approx}4{sigma} level, providing the first image of CMB lensing convergence. We cross-correlate this map with Herschel/SPIRE maps covering 90 deg{sup 2} at wavelengths of 500, 350, and 250 {mu}m. We show that these submillimeter (submm) wavelength maps are strongly correlated with the lensing convergence map, with detection significances in each of the three submm bands ranging from 6.7{sigma} to 8.8{sigma}. We fit the measurement of the cross power spectrum assuming a simple constant bias model and infer bias factors of b = 1.3-1.8, with a statistical uncertainty of 15%, depending on the assumed model for the redshift distribution of the dusty galaxies that are contributing to the Herschel/SPIRE maps.

Holder, G. P.; De Haan, T.; Dobbs, M. A.; Dudley, J. [Department of Physics, McGill University, Montreal, Quebec H3A 2T8 (Canada); Viero, M. P.; Bock, J. [California Institute of Technology, Pasadena, CA 91125 (United States); Zahn, O. [Berkeley Center for Cosmological Physics, Department of Physics, University of California, and Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Aird, K. A. [University of Chicago, Chicago, IL 60637 (United States); Benson, B. A.; Bhattacharya, S.; Bleem, L. E.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Crites, A. T. [Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States); Brodwin, M. [Department of Physics and Astronomy, University of Missouri, Kansas City, MO 64110 (United States); Cho, H-M. [NIST Quantum Devices Group, Boulder, CO 80305 (United States); Conley, A. [Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO 80309 (United States); George, E. M. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Halverson, N. W. [Department of Astrophysical and Planetary Sciences and Department of Physics, University of Colorado, Boulder, CO 80309 (United States); and others

2013-07-01T23:59:59.000Z

236

NEW SOURCES OF RADIATION  

E-Print Network [OSTI]

Stanford Synchrotron Radiation Project Report No. 75/07.IBL 79M0733 Fig. 20. Radiation emission pattern by electronsWinick, Stanford Synchrotron Radiation Laboratory. Fig. 21.

Schimmerling, W.

2010-01-01T23:59:59.000Z

237

Radiation-induced angiosarcoma  

E-Print Network [OSTI]

1a Figure 1b Figure 1. Radiation-induced angiosarcoma in afollowing completion of radiation therapy. Figure 2a Figurecell histiocytosis after radiation for breast carcinoma: can

Anzalone, C Lane; Cohen, Philip R; Diwan, Abdul H; Prieto, Victor G

2013-01-01T23:59:59.000Z

238

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...

239

Matter Wave Radiation Leading to Matter Teleportation  

E-Print Network [OSTI]

The concept of matter wave radiation is put forward, and its equation is established for the first time. The formalism solution shows that the probability density is a function of displacement and time. A free particle and a two-level system are reinvestigated considering the effect of matter wave radiation. Three feasible experimental designs, especially a modified Stern-Gerlach setup, are proposed to verify the existence of matter wave radiation. Matter wave radiation effect in relativity has been formulated in only a raw formulae, which offers another explanation of Lamb shift. A possible mechanics of matter teleportation is predicted due to the effect of matter wave radiation.

Yong-Yi Huang

2015-02-12T23:59:59.000Z

240

Background modeling for the GERDA experiment  

SciTech Connect (OSTI)

The neutrinoless double beta (0???) decay experiment GERDA at the LNGS of INFN has started physics data taking in November 2011. This paper presents an analysis aimed at understanding and modeling the observed background energy spectrum, which plays an essential role in searches for a rare signal like 0??? decay. A very promising preliminary model has been obtained, with the systematic uncertainties still under study. Important information can be deduced from the model such as the expected background and its decomposition in the signal region. According to the model the main background contributions around Q{sub ??} come from {sup 214}Bi, {sup 228}Th, {sup 42}K, {sup 60}Co and ? emitting isotopes in the {sup 226}Ra decay chain, with a fraction depending on the assumed source positions.

Becerici-Schmidt, N. [Max-Planck-Institut für Physik, München (Germany)] [Max-Planck-Institut für Physik, München (Germany); Collaboration: GERDA Collaboration

2013-08-08T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Neutrino interaction with background matter in a noninertial frame  

E-Print Network [OSTI]

We study Dirac neutrinos propagating in rotating background matter. First we derive the Dirac equation for a single massive neutrino in the noninertial frame, where matter is at rest. This equation is written in the effective curved space-time corresponding to the corotating frame. We find the exact solution of the Dirac equation. The neutrino energy levels for ultrarelativistic particles are obtained. Then we discuss several neutrino mass eigenstates, with a nonzero mixing between them, interacting with rotating background matter. We derive the effective Schr\\"{o}dinger equation governing neutrino flavor oscillations in rotating matter. The new resonance condition for neutrino oscillations is obtained. We also examine the correction to the resonance condition caused by the matter rotation.

Dvornikov, Maxim

2015-01-01T23:59:59.000Z

242

What are the galaxies contributing to the Cosmic Infrared Background ?  

E-Print Network [OSTI]

Recent optical observations have led to a significant progress in our understanding of galaxy formation and evolution. However, our view on the deep universe is currently limited to the starlight which directly escapes from high-redshift galaxies, since we so far ignore the fraction of luminosity absorbed by dust and released in the IR/submm wavelength range. A new constraint is set by the possible detection of the Cosmic Infrared Background. We briefly review the observations and use a semi-analytic model of galaxy formation and evolution to predict number counts consistent with the level of the background. It turns out that the predictions fairly accomodate preliminary data at 175 and 850 microns. This suggests that a significant fraction of star/galaxy formation at high z is hidden by dust.

B. Guiderdoni

1997-12-29T23:59:59.000Z

243

Optical emission line monitor with background observation and cancellation  

DOE Patents [OSTI]

A fiber optics based optical emission line monitoring system is provided in which selected spectral emission lines, such as the sodium D-line emission in coal combustion, may be detected in the presence of interferring background or blackbody radiation with emissions much greater in intensity than that of the emission line being detected. A bifurcated fiber optic light guide is adapted at the end of one branch to view the combustion light which is guided to a first bandpass filter, adapted to the common trunk end of the fiber. A portion of the light is reflected back through the common trunk portion of the fiber to a second bandpass filter adapted to the end of the other branch of the fiber. The first filter bandpass is centered at a wavelength corresponding to the emission line to be detected with a bandwidth of about three nanometers (nm). The second filter is centered at the same wavelength but having a width of about 10 nm. First and second light detectors are located to view the light passing through the first and second filters respectively. Thus, the second detector is blind to the light corresponding to the emission line of interest detected by the first detector and the difference between the two detector outputs is uniquely indicative of the intensity of only the combustion flame emission of interest. This instrument can reduce the effects of interferring blackbody radiation by greater than 20 dB.

Goff, David R. (Star City, WV); Notestein, John E. (Morgantown, WV)

1986-01-01T23:59:59.000Z

244

Optical emission line monitor with background observation and cancellation  

DOE Patents [OSTI]

A fiber optics based optical emission line monitoring system is provided in which selected spectral emission lines, such as the sodium D-line emission in coal combustion, may be detected in the presence of interferring background or blackbody radiation with emissions much greater in intensity than that of the emission line being detected. A bifurcated fiber optic light guide is adapted at the end of one branch to view the combustion light which is guided to a first bandpass filter, adapted to the common trunk end of the fiber. A portion of the light is reflected back through the common trunk portion of the fiber to a second bandpass filter adapted to the end of the other branch of the fiber. The first filter bandpass is centered at a wavelength corresponding to the emission line to be detected with a bandwidth of about three nanometers (nm). The second filter is centered at the same wavelength but having a width of about 10 nm. First and second light detectors are located to view the light passing through the first and second filters respectively. Thus, the second detector is blind to the light corresponding to the emission line of interest detected by the first detector and the difference between the two detector outputs is uniquely indicative of the intensity of only the combustion flame emission of interest. This instrument can reduce the effects of interfering blackbody radiation by greater than 20 dB.

Goff, D.R.; Notestein, J.E.

1985-01-04T23:59:59.000Z

245

Cosmic Microwave Background Tests of Inflation  

E-Print Network [OSTI]

Inflation provides a unified paradigm for understanding the isotropy of the cosmic microwave background (CMB), the flatness problem, and the origin of large-scale structure. Although the physics responsible for inflation is not yet well understood, slow-roll inflation generically makes several predictions: a flat Universe, primordial adiabatic density perturbations, and a stochastic gravity-wave background. Inflation further predicts specific relations between the amplitudes and shapes of the spectrum of density perturbations and gravity waves. There are now excellent prospects for testing precisely these predictions with forthcoming CMB temperature and polarization maps. Here I discuss these new CMB tests of inflation.

Marc Kamionkowski

1998-03-14T23:59:59.000Z

246

Atomistic simulations of radiation damage in amorphous metal alloys  

E-Print Network [OSTI]

While numerous fundamental studies have characterized the atomic-level radiation response mechanisms in irradiated crystalline alloys, comparatively little is known regarding the mechanisms of radiation damage in amorphous ...

Baumer, Richard E. (Richard Edward)

2013-01-01T23:59:59.000Z

247

Background field method and nonrelativistic QED matching  

E-Print Network [OSTI]

We discuss the resolution of an inconsistency between lattice background field methods and nonrelativistic QED matching conditions. In particular, we show that lack of on-shell conditions in lattice QCD with time-dependent background fields generally requires that certain operators related by equations of motion should be retained in an effective field theory to correctly describe the behavior of Green's functions. The coefficients of such operators in a nonrelativistic hadronic theory are determined by performing a robust nonrelativistic expansion of QED for relativistic scalar and spin-half hadrons including nonminimal electromagnetic couplings. Provided that nonrelativistic QED is augmented with equation-of-motion operators, we find that the background field method can be reconciled with the nonrelativistic QED matching conditions without any inconsistency. We further investigate whether nonrelativistic QED can be employed in the analysis of lattice QCD correlation function in background fields, but we are confronted with difficulties. Instead, we argue that the most desirable approach is a hybrid one which relies on a relativistic hadronic theory with operators chosen based on their relevance in the nonrelativistic limit. Using this hybrid framework, we obtain practically useful forms of correlation functions for scalar and spin-half hadrons in uniform electric and magnetic fields.

Jong-Wan Lee; Brian C. Tiburzi

2014-11-15T23:59:59.000Z

248

Background Material Important Questions about Magnetism  

E-Print Network [OSTI]

Background Material Important Questions about Magnetism: 1) What is Magnetism?Magnetism is a force or repulsion due to charge is called the electric force. But what about magnetism, is there a fundamental property of some matter that makes things magnetic? The answer is: "sort of." Electric current

Mojzsis, Stephen J.

249

UCHC Lockout/Tagout Policy Background  

E-Print Network [OSTI]

UCHC Lockout/Tagout Policy (4/09) Background: This safety policy is applicable to all Health Center: Lockout will be utilized for equipment which is designed with a lockout capability. A valve that can be locked out with a chain is considered as having a lockout capability. Only the Office of Research Safety

Kim, Duck O.

250

CHAPTER 1 INTRODUCTION 1.1 Background  

E-Print Network [OSTI]

1 CHAPTER 1 INTRODUCTION 1.1 Background This thesis describes a multi-agent based architecture of the research and an outline plan for the rest of this thesis complete the chapter. 1.2 Software Project and monitor progress to check the development is on time and within budget. #12;3 1.3 Software Project

O'Connor, Rory

251

1 Introduction 1.1 Background  

E-Print Network [OSTI]

#12;#12;3 1 Introduction 1.1 Background Research method is a relevant topic to anybody performing. 1.2 Classical Research, Technology and Technology Research The term research is defined in several different ways. According to Merriam-Webster [1], research is "investigation or experimentation aimed

Stølen, Ketil

252

Cosmic IR Backgrounds Ned Wright (UCLA)  

E-Print Network [OSTI]

Cosmic IR Backgrounds by Ned Wright (UCLA) http://www.astro.ucla.edu/~wright/intro.html See: · http://www.astro.ucla.edu/~wright/cosmolog.htm · http://www.astro.ucla.edu/~wright/DIRBE · http://www.astro.ucla.edu/~wright/CIBR · http

Wright, Edward L. "Ned"

253

2013 National Geothermal Student Competition Background  

E-Print Network [OSTI]

1 2013 National Geothermal Student Competition Background: The 2013 National Geothermal Student, is designed to advance the understanding of geothermal energy as a valued resource by promoting innovation to engage students in a collaborative exercise to develop a business plan for developing a geothermal

Carrington, Emily

254

Background Simulations for the International Linear Collider  

E-Print Network [OSTI]

on superconducting technology to collide bunches of electrons and positrons. The baseline configuration (about 31 km in a clean experimental environment with low backgrounds. The LHC will likely discover the Higgs boson accelerator directly. DESY FLC, 22603 Hamburg, Germany, adrian.vogel@desy.de 1 #12;Figure 1: Overall view

255

Radiation exposure in X-ray-based imaging techniques used in osteoporosis  

E-Print Network [OSTI]

to low levels of ionizing radiation: BEIR VII Phase 2. TheBlake G, Genant HK (1999) Radiation exposure in bone mineralGuglielmi Thomas M. Link Radiation exposure in X-ray-based

Damilakis, John; Adams, Judith E.; Guglielmi, Giuseppe; Link, Thomas M.

2010-01-01T23:59:59.000Z

256

Radiation of a neutral polarizable particle moving uniformly through a thermal radiation field  

E-Print Network [OSTI]

We discuss the properties of thermal electromagnetic radiation produced by a neutral polarizable nanoparticle moving with an arbitrary relativistic velocity in a heated vacuum background with a fixed temperature. We show that the particle in its own rest frame acquires the radiation temperature of vacuum, multiplied by a velocity-dependent factor, and then emits thermal photons predominantly in the forward direction. The intensity of radiation proves to be much higher than for the particle at rest. For metal particles with high energy, the ratio of emitted and absorbed radiation power is proportional to the Lorentz-factor squared.

G. V. Dedkov; A. A. Kyasov

2014-06-25T23:59:59.000Z

257

Entanglement from thermal black body radiation  

E-Print Network [OSTI]

Two non--interacting quantum systems which couple to a common environment with many degrees of freedom initially in thermal equilibrium can become entangled due to the indirect interaction mediated through this heat bath. I examine here the dynamics of reservoir induced entanglement for a heat bath consisting of a thermal electro--magnetic radiation field, such as black body radiation or the cosmic microwave background, and show how the effect can be understood as result of an effective induced interaction.

Daniel Braun

2005-09-06T23:59:59.000Z

258

Non-thermal Cosmic Backgrounds from Blazars: the contribution to the CMB, X-ray and gamma-ray Backgrounds  

E-Print Network [OSTI]

We present a new assessment of the contribution of Blazars to the extragalactic background radiation across the e.m. spectrum. Our calculations rely on deep Blazar radio counts that we derived combining several multifrequency surveys. The integrated Blazar emission yields a broad-band non-thermal background that in some parts of the e.m. spectrum dominates the extragalactic brightness. Blazars are the main point-like contributors to the CMB. Their integrated emission causes an apparent T increase of 5-50 muK in the 50-250 GHz range. The CMB fluctuation spectrum is sensibly contaminated at l>300, for a Poissonian source distribution, or at lower l values if spatial clustering is present. We estimate that well over 100,000 Blazars will produce a significant signal in the PLANCK CMB anisotropy maps. Because of the microwave-Xray flux correlation, these sources are expected to have flux > a few 10^{-15} erg/s in the soft X-ray band. Thus, a large fraction of the foreground sources in CMB anisotropy maps could be ...

Giommi, P; Cavazzuti, E; Perri, M; Pittori, C

2006-01-01T23:59:59.000Z

259

Handheld CZT radiation detector  

DOE Patents [OSTI]

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.

Murray, William S.; Butterfield, Kenneth B.; Baird, William

2004-08-24T23:59:59.000Z

260

An upper bound from helioseismology on the stochastic background of gravitational waves  

E-Print Network [OSTI]

The universe is expected to be permeated by a stochastic background of gravitational radiation of astrophysical and cosmological origin. This background is capable of exciting oscillations in solar-like stars. Here we show that solar-like oscillators can be employed as giant hydrodynamical detectors for such a background in the muHz to mHz frequency range, which has remained essentially unexplored until today. We demonstrate this approach by using high-precision radial velocity data for the Sun to constrain the normalized energy density of the stochastic gravitational-wave background around 0.11 mHz. These results open up the possibility for asteroseismic missions like CoRoT and Kepler to probe fundamental physics.

Daniel M. Siegel; Markus Roth

2014-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Properties of Natural Radiation and Radioactivity  

SciTech Connect (OSTI)

Ubiquitous natural sources of radiation and radioactive material (naturally occurring radioactive material, NORM) have exposed humans throughout history. To these natural sources have been added technologically-enhanced naturally occurring radioactive material (TENORM) sources and human-made (anthropogenic) sources. This chapter describes the ubiquitous radiation sources that we call background, including primordial radionuclides such as 40K, 87Rb, the 232Th series, the 238U series, and the 235U series; cosmogenic radionuclides such as 3H and 14C; anthropogenic radionuclides such as 3H, 14C, 137Cs, 90Sr, and 129I; radiation from space; and radiation from technologically-enhanced concentrations of natural radionuclides, particularly the short-lived decay products of 222Rn ("radon") and 220Rn ("thoron") in indoor air. These sources produce radiation doses to people principally via external irradiation or internal irradiation following intakes by inhalation or ingestion. The effective doses from each are given, with a total of 3.11 mSv y-1 (311 mrem y-1) to the average US resident. Over 2.5 million US residents receive over 20 mSv y-1 (2 rem y-1), primarily due to indoor radon. Exposure to radiation from NORM and TENORM produces the largest fraction of ubiquitous background exposure to US residents, on the order of 2.78 mSv (278 mrem) or about 89%. This is roughly 45% of the average annual effective dose to a US resident of 6.2 mSv y-1 (620 mrem y-1) that includes medical (48%), consumer products and air travel (2%), and occupational and industrial (0.1%). Much of this chapter is based on National Council on Radiation Protection and Measurements (NCRP) Report No. 160, "Ionizing Radiation Exposure of the Population of the United States," for which the author chaired the subcommittee that wrote Chapter 3 on "Ubiquitous Background Radiation."

Strom, Daniel J.

2009-07-13T23:59:59.000Z

262

Design Considerations for Large Mass Ultra-Low Background Experiments  

SciTech Connect (OSTI)

Summary The objective of this document is to present the designers of the next generation of large-mass, ultra-low background experiments with lessons learned and design strategies from previous experimental work. Design issues divided by topic into mechanical, thermal and electrical requirements are addressed. Large mass low-background experiments have been recognized by the scientific community as appropriate tools to aid in the refinement of the standard model. The design of these experiments is very costly and a rigorous engineering review is required for their success. The extreme conditions that the components of the experiment must withstand (heavy shielding, vacuum/pressure and temperature gradients), in combination with unprecedented noise levels, necessitate engineering guidance to support quality construction and safe operating conditions. Physical properties and analytical results of typical construction materials are presented. Design considerations for achieving ultra-low-noise data acquisition systems are addressed. Five large-mass, low-background conceptual designs for the one-tonne scale germanium experiment are proposed and analyzed. The result is a series of recommendations for future experiments engineering and for the Majorana simulation task group to evaluate the different design approaches.

Aguayo Navarrete, Estanislao; Reid, Douglas J.; Fast, James E.; Orrell, John L.

2011-07-01T23:59:59.000Z

263

Foreign Energy Company Competitiveness: Background information  

SciTech Connect (OSTI)

This report provides background information to the report Energy Company Competitiveness: Little to Do With Subsidies (DOE 1994). The main body of this publication consists of data uncovered during the course of research on this DOE report. This data pertains to major government energy policies in each country studied. This report also provides a summary of the DOE report. In October 1993, the Office of Energy Intelligence, US Department of Energy (formerly the Office of Foreign Intelligence), requested that Pacific Northwest Laboratory prepare a report addressing policies and actions used by foreign governments to enhance the competitiveness of their energy firms. Pacific Northwest Laboratory prepared the report Energy Company Competitiveness Little to Do With Subsidies (DOE 1994), which provided the analysis requested by DOE. An appendix was also prepared, which provided extensive background documentation to the analysis. Because of the length of the appendix, Pacific Northwest Laboratory decided to publish this information separately, as contained in this report.

Weimar, M.R.; Freund, K.A.; Roop, J.M.

1994-10-01T23:59:59.000Z

264

Cosmic Microwave Background: Past, Future, and Present  

E-Print Network [OSTI]

I explain the origin and evolution of anisotropies in the Cosmic Microwave Background (CMB) and argue that upcoming experiments will measure cosmological and fundamental parameters very accurately. Most of the paper focuses on present data, which strongly suggest that the universe is flat. Several arguments are given to prove that present data sets are not contaminated by systematics. New techniques to compare different experiments visually are introduced. These are illustrated for two years of the MSAM and Python experiments.

Scott Dodelson

1999-12-22T23:59:59.000Z

265

Sideband Mixing in Intense Laser Backgrounds  

E-Print Network [OSTI]

The electron propagator in a laser background has been shown to be made up of a series of sideband poles. In this paper we study this decomposition by analysing the impact of the residual gauge freedom in the Volkov solution on the sidebands. We show that the gauge transformations do not alter the location of the poles. The identification of the propagator from the two-point function is maintained but we show that the sideband structures mix under residual gauge transformations.

Martin Lavelle; David McMullan

2014-07-04T23:59:59.000Z

266

A background free double beta decay experiment  

E-Print Network [OSTI]

We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is to use the Spherical Proportional Counter that provides two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of their higher density, the considered process is out of energy range. An alternative solution could be the development of double decay emitters with lower density by using for instance the aerogel technique. It is surprising that a technology used for particle identification in high-energy physics becomes a powerful tool for rejecting backgrounds in such low-energy experiments.

Ioannis Giomataris

2010-12-20T23:59:59.000Z

267

Radiative heat transfer between dielectric bodies  

E-Print Network [OSTI]

The recent development of a scanning thermal microscope (SThM) has led to measurements of radiative heat transfer between a heated sensor and a cooled sample down to the nanometer range. This allows for comparision of the known theoretical description of radiative heat transfer, which is based on fluctuating electrodynamics, with experiment. The theory itself is a macroscopic theory, which can be expected to break down at distances much smaller than 10-8m. Against this background it seems to be reasonable to revisit the known macroscopic theory of fluctuating electrodynamics and of radiative heat transfer.

Svend-Age Biehs

2011-03-16T23:59:59.000Z

268

Alpha 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICE OF RESEARCHThermal SolarAllocatioBasics of Radiation Gamma

269

Yale ME Turbine Test cell instructions Background  

E-Print Network [OSTI]

level o Lubrication oil level- within 2-4 inches from top of tank. Air Inlet Closed Air Inlet open combustion gas backflow into the lab space. Test Cell preparation: 1. Turn on Circuit breakers # 16 Picture at right shows access door open With fuel on left and lube oil on right #12;o Starting Air Supply

Haller, Gary L.

270

The impact of non-Planckian effects on radio cosmological backgrounds  

E-Print Network [OSTI]

Non-Planckian (NP) spectral modifications of the CMB radiation spectrum can be produced due to the existence of a non-zero value of the plasma frequency at the recombination epoch. We present here an analysis of NP effects on the radio cosmological background and we derive, for the first time, predictions of their amplitude on three different observables: the CMB spectrum, the Sunyaev-Zel'dovich (SZ) effect in cosmic structures, and the 21-cm background temperature brightness change. We find that NP effect can manifest in the CMB spectrum at $\

Colafrancesco, Sergio; Marchegiani, Paolo

2015-01-01T23:59:59.000Z

271

RESOLVING THE RADIO SOURCE BACKGROUND: DEEPER UNDERSTANDING THROUGH CONFUSION  

SciTech Connect (OSTI)

We used the Karl G. Jansky Very Large Array to image one primary beam area at 3 GHz with 8'' FWHM resolution and 1.0 {mu}Jy beam{sup -1} rms noise near the pointing center. The P(D) distribution from the central 10 arcmin of this confusion-limited image constrains the count of discrete sources in the 1 < S({mu}Jy) < 10 range. At this level, the brightness-weighted differential count S {sup 2} n(S) is converging rapidly, as predicted by evolutionary models in which the faintest radio sources are star-forming galaxies; and Almost-Equal-To 96% of the background originating in galaxies has been resolved into discrete sources. About 63% of the radio background is produced by active galactic nuclei (AGNs), and the remaining 37% comes from star-forming galaxies that obey the far-infrared (FIR)/radio correlation and account for most of the FIR background at {lambda} Almost-Equal-To 160 {mu}m. Our new data confirm that radio sources powered by AGNs and star formation evolve at about the same rate, a result consistent with AGN feedback and the rough correlation of black hole and stellar masses. The confusion at centimeter wavelengths is low enough that neither the planned Square Kilometre Array nor its pathfinder ASKAP EMU survey should be confusion limited, and the ultimate source detection limit imposed by 'natural' confusion is {<=}0.01 {mu}Jy at {nu} = 1.4 GHz. If discrete sources dominate the bright extragalactic background reported by ARCADE 2 at 3.3 GHz, they cannot be located in or near galaxies and most are {<=}0.03 {mu}Jy at 1.4 GHz.

Condon, J. J.; Cotton, W. D.; Fomalont, E. B.; Kellermann, K. I. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Miller, N. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Perley, R. A. [National Radio Astronomy Observatory, P.O. Box 0, Socorro, NM 87801 (United States); Scott, D.; Vernstrom, T.; Wall, J. V. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1C1 (Canada)

2012-10-10T23:59:59.000Z

272

Measurements of Worldwide Radioxenon Backgrounds - The "EU" Project  

SciTech Connect (OSTI)

Under the Comprehensive Nuclear-Test-Ban Treaty (CTBT), radioactive xenon (radioxenon) measurements are one of the principle techniques used to detect nuclear underground nuclear explosions, and specifically, the presence of one or more radioxenon isotopes allows one to determine whether a suspected event was a nuclear explosion or originated from an innocent source. During the design of the International Monitoring System (IMS), which was designed as the verification mechanism for the Treaty, it was determined that radioxenon measurements should be performed at 40 or more stations worldwide. At the time of the design of the IMS, however, very few details about the background of the xenon isotopes was known and it is now recognized that the backgrounds were probably evolving anyhow. This paper lays out the beginning of a study of the worldwide concentrations of xenon isotopes that can be used to detect nuclear explosions and several sources that also release radioxenons, and will have to be accounted for during analysis of atmospheric levels. Although the global concentrations of the xenon isotopes are the scope of a much larger activity that could span over several years, this study measures radioxenon concentrations in locations where there was either very little information or there was a unique opportunity to learn more about emissions from known sources. The locations where radioxenon levels were measured and reported are included.

Bowyer, Ted W.; Cooper, Matthew W.; Hayes, James C.; Forrester, Joel B.; Haas, Derek A.; Hansen, Randy R.; Keller, Paul E.; Kirkham, Randy R.; Lidey, Lance S.; McIntyre, Justin I.; Miley, Harry S.; Payne, Rosara F.; Saey, Paul R.; Thompson, Robert C.; Woods, Vincent T.; Williams, Richard M.

2009-09-24T23:59:59.000Z

273

The {ital COBE} Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background. I. Limits and Detections  

SciTech Connect (OSTI)

The Diffuse Infrared Background Experiment (DIRBE) on the Cosmic Background Explorer ({ital COBE}) spacecraft was designed primarily to conduct a systematic search for an isotropic cosmic infrared background (CIB) in 10 photometric bands from 1.25 to 240 {mu}m. The results of that search are presented here. Conservative limits on the CIB are obtained from the minimum observed brightness in all-sky maps at each wavelength, with the faintest limits in the DIRBE spectral range being at 3.5 {mu}m ({nu}{ital I}{sub {nu}} {lt} 64 nW m{sup {minus}2} sr{sup {minus}1}, 95{percent} confidence level) and at 240 {mu}m ({nu}{ital I}{sub {nu}} {lt} 28 nW m{sup {minus}2} sr{sup {minus}1}, 95{percent} confidence level). The bright foregrounds from interplanetary dust scattering and emission, stars, and interstellar dust emission are the principal impediments to the DIRBE measurements of the CIB. These foregrounds have been modeled and removed from the sky maps. Assessment of the random and systematic uncertainties in the residuals and tests for isotropy show that only the 140 and 240 {mu}m data provide candidate detections of the CIB. The residuals and their uncertainties provide CIB upper limits more restrictive than the dark sky limits at wavelengths from 1.25 to 100 {mu}m. No plausible solar system or Galactic source of the observed 140 and 240 {mu}m residuals can be identified, leading to the conclusion that the CIB has been detected at levels of {nu}{ital I}{sub {nu}} = 25 {plus_minus} 7 and 14 {plus_minus} 3 nW m{sup {minus}2} sr{sup {minus}1} at 140 and 240 {mu}m, respectively. The integrated energy from 140 to 240 {mu}m, 10.3 nW m{sup {minus}2} sr{sup {minus}1}, is about twice the integrated optical light from the galaxies in the Hubble Deep Field, suggesting that star formation might have been heavily enshrouded by dust at high redshift. The detections and upper limits reported here provide new constraints on models of the history of energy-releasing processes and dust production since the decoupling of the cosmic microwave background from matter. {copyright} {ital {copyright} 1998.} {ital The American Astronomical Society}

Hauser, M.G. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)] [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Arendt, R.G. [Raytheon STX, Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [Raytheon STX, Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kelsall, T.; Dwek, E. [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Odegard, N.; Weiland, J.L.; Freudenreich, H.T. [Raytheon STX, Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [Raytheon STX, Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Reach, W.T. [California Institute of Technology, IPAC/JPL, MS 100-22, Pasadena, CA 91125 (United States)] [California Institute of Technology, IPAC/JPL, MS 100-22, Pasadena, CA 91125 (United States); Silverberg, R.F.; Moseley, S.H. [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Pei, Y.C. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)] [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Lubin, P. [Physics Department, University of California at Santa Barbara, Santa Barbara, CA 93106 (United States)] [Physics Department, University of California at Santa Barbara, Santa Barbara, CA 93106 (United States); Mather, J.C.; Shafer, R.A. [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Smoot, G.F. [Lawrence Berkeley Laboratory, Space Sciences Laboratory, Department of Physics, UC Berkeley, CA 94720 (United States)] [Lawrence Berkeley Laboratory, Space Sciences Laboratory, Department of Physics, UC Berkeley, CA 94720 (United States); Weiss, R. [Massachusetts Institute of Technology, Room 20F-001, Department of Physics, Cambridge, MA 02139 (United States)] [Massachusetts Institute of Technology, Room 20F-001, Department of Physics, Cambridge, MA 02139 (United States); Wilkinson, D.T. [Princeton University, Department of Physics, Jadwin Hall, Box 708, Princeton, NJ 08544 (United States)] [Princeton University, Department of Physics, Jadwin Hall, Box 708, Princeton, NJ 08544 (United States); Wright, E.L. [UCLA, Astronomy Department, Los Angeles, CA 90024-1562 (United States)] [UCLA, Astronomy Department, Los Angeles, CA 90024-1562 (United States)

1998-11-01T23:59:59.000Z

274

Cellular telephone-based wide-area radiation detection network  

DOE Patents [OSTI]

A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

Craig, William W. (Pittsburg, CA); Labov, Simon E. (Berkeley, CA)

2009-06-09T23:59:59.000Z

275

New physics from the Cosmic Microwave Background  

E-Print Network [OSTI]

I review the present status of the Cosmic Microwave Background, with some emphasis on the current and future implications for particle physics. Conclusions are: gravitational instability in a dark matter dominated universe grew today's structure; the Universe remained neutral until z<~50; the CMB power spectrum peaks at 150<~l<~350; the large-scale structure of spacetime appears to be simple; something like inflation is something like proven; we will learn a great deal about cosmology, astrophysics and particle physics from MAP and Planck.

Douglas Scott

1999-11-17T23:59:59.000Z

276

Superconducting Hair on Charged Black String Background  

E-Print Network [OSTI]

Behaviour of Dirac fermions in the background of a charged black string penetrated by an Abelian Higgs vortex is elaborated. One finds the evidence that the system under consideration can support fermion fields acting like a superconducting cosmic string in the sence that a nontrivial Dirac fermion field can be carried by the system in question. The case of nonextremal and extremal black string vortex systems were considered. The influence of electric and Higgs charge, the winding number and the fermion mass on the fermion localization near the black string event horizon was studied. It turned out that the extreme charged black string expelled fermion fields more violently comparing to the nonextremal one.

Lukasz Nakonieczny; Marek Rogatko

2012-01-25T23:59:59.000Z

277

Adaptors for radiation detectors  

DOE Patents [OSTI]

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.

Livesay, Ronald Jason

2014-04-22T23:59:59.000Z

278

A background free double beta decay experiment  

E-Print Network [OSTI]

We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is to use the Spherical Proportional Counter that provides two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of their higher density, the considered process is out of energy range. An alternative solution could be the development of double decay emitters with lower density by using for instance the aerogel technique. It is surprising that a te...

Giomataris, Ioannis

2010-01-01T23:59:59.000Z

279

Radiation measurements of uranium ingots from the electrometallurgical treatment of spent fuel.  

SciTech Connect (OSTI)

Radiation measurements and gamma spectroscopy analyses were made on numerous uranium ingots produced during the treatment of Experimental Breeder Reactor-II (EBR-II) spent nuclear fuel. The objective of these measurements was to provide background data for shielding concerns and potential process optimization. The uranium ingots resulted from the processing of both driver and blanket fuel by the electrometallurgical treatment process. The observed variation in the measurements was traced to the levels of certain fission product residues that remained in the uranium ingots produced during spent fuel treatment. A minor process change to hold the material at an elevated temperature for a specified length of time was found to significantly reduce concentrations of high-activity fission products and, thus the radiation field.

Westphal, B. R.; Liaw, J. R.; Krsul, J. R.; Maddison, D. W.; Jensen, B. A.

2003-03-24T23:59:59.000Z

280

RADIATION SAFETY OFFICE UNIVERSITYOF MARYLAND  

E-Print Network [OSTI]

RADIATION SAFETY OFFICE UNIVERSITYOF MARYLAND RADIATION SAFETY MANUAL UNIVERSITY OF MARYLAND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2. Radiation Safety Committee (RSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.4. Radiation Safety Office (RSO

Rubloff, Gary W.

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

The White Dwarf -- White Dwarf galactic background in the LISA data  

E-Print Network [OSTI]

LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low-part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. Since the galactic white-dwarfs background will be observed by LISA not as a stationary but rather as a cyclostationary random process with a period of one year, we summarize the theory of cyclostationary random processes, present the corresponding generalized spectral method needed to characterize such process, and make a comparison between our analytic results and those obtained by applying our method to the simulated data. We find that, by measuring the generalized spectral components of the white-dwarf background, LISA will be able to infer properties of the distribution of the white-dwarfs binary systems present in our Galaxy.

Jeffrey A. Edlund; Massimo Tinto; Andrzej Krolak; Gijs Nelemans

2005-04-22T23:59:59.000Z

282

Neural networks and separation of Cosmic Microwave Background and astrophysical signals in sky maps  

E-Print Network [OSTI]

The Independent Component Analysis (ICA) algorithm is implemented as a neural network for separating signals of different origin in astrophysical sky maps. Due to its self-organizing capability, it works without prior assumptions on the signals, neither on their frequency scaling, nor on the signal maps themselves; instead, it learns directly from the input data how to separate the physical components, making use of their statistical independence. To test the capabilities of this approach, we apply the ICA algorithm on sky patches, taken from simulations and observations, at the microwave frequencies, that are going to be deeply explored in a few years on the whole sky, by the Microwave Anisotropy Probe (MAP) and by the {\\sc Planck} Surveyor Satellite. The maps are at the frequencies of the Low Frequency Instrument (LFI) aboard the {\\sc Planck} satellite (30, 44, 70 and 100 GHz), and contain simulated astrophysical radio sources, Cosmic Microwave Background (CMB) radiation, and Galactic diffuse emissions from thermal dust and synchrotron. We show that the ICA algorithm is able to recover each signal, with precision going from 10% for the Galactic components to percent for CMB; radio sources are almost completely recovered down to a flux limit corresponding to $0.7\\sigma_{CMB}$, where $\\sigma_{CMB}$ is the rms level of CMB fluctuations. The signal recovering possesses equal quality on all the scales larger then the pixel size. In addition, we show that the frequency scalings of the input signals can be partially inferred from the ICA outputs, at the percent precision for the dominant components, radio sources and CMB.

C. Baccigalupi; L. Bedini; C. Burigana; G. De Zotti; A. Farusi; D. Maino; M. Maris; F. Perrotta; E. Salerno; L. Toffolatti; A. Tonazzini

2000-06-21T23:59:59.000Z

283

Gravitational wave background from Standard Model physics: Qualitative features  

E-Print Network [OSTI]

Because of physical processes ranging from microscopic particle collisions to macroscopic hydrodynamic fluctuations, any plasma in thermal equilibrium emits gravitational waves. For the largest wavelengths the emission rate is proportional to the shear viscosity of the plasma. In the Standard Model at T > 160 GeV, the shear viscosity is dominated by the most weakly interacting particles, right-handed leptons, and is relatively large. We estimate the order of magnitude of the corresponding spectrum of gravitational waves. Even though at small frequencies (corresponding to the sub-Hz range relevant for planned observatories such as eLISA) this background is tiny compared with that from non-equilibrium sources, the total energy carried by the high-frequency part of the spectrum is non-negligible if the production continues for a long time. We suggest that this may constrain (weakly) the highest temperature of the radiation epoch. Observing the high-frequency part directly sets a very ambitious goal for future ge...

Ghiglieri, J

2015-01-01T23:59:59.000Z

284

Project Lyman: Quantifying 11 Gyrs of Metagalactic Ionizing Background Evolution  

E-Print Network [OSTI]

The timing and duration of the reionization epoch is crucial to the emergence and evolution of structure in the universe. The relative roles that star-forming galaxies, active galactic nuclei and quasars play in contributing to the metagalactic ionizing background across cosmic time remains uncertain. Deep quasar counts provide insights into their role, but the potentially crucial contribution from star-formation is highly uncertain due to our poor understanding of the processes that allow ionizing radiation to escape into the intergalactic medium (IGM). The fraction of ionizing photons that escape from star-forming galaxies is a fundamental free parameter used in models to "fine-tune" the timing and duration of the reionization epoch that occurred somewhere between 13.4 and 12.7 Gyrs ago (redshifts between 12 > z > 6). However, direct observation of Lyman continuum (LyC) photons emitted below the rest frame \\ion{H}{1} ionization edge at 912 \\AA\\ is increasingly improbable at redshifts z > 3, due to the stead...

McCandliss, Stephan R; Bergvall, Nils; Bianchi, Luciana; Bridge, Carrie; Bogosavljevic, Milan; Cohen, Seth H; Deharveng, Jean-Michel; Dixon, W Van Dyke; Ferguson, Harry; Friedman, Peter; Hayes, Matthew; Howk, J Christopher; Inoue, Akio; Iwata, Ikuru; Kaiser, Mary Elizabeth; Kriss, Gerard; Kruk, Jeffrey; Kutyrev, Alexander S; Leitherer, Claus; Meurer, Gerhardt R; Prochaska, Jason X; Sonneborn, George; Stiavelli, Massimo; Teplitz, Harry I; Windhorst, Rogier A

2012-01-01T23:59:59.000Z

285

Dusty Infrared Galaxies: Sources of the Cosmic Infrared Background  

E-Print Network [OSTI]

The discovery of the Cosmic Infrared Background (CIB) in 1996, together with recent cosmological surveys from the mid-infrared to the millimeter have revolutionized our view of star formation at high redshifts. It has become clear, in the last decade, that a population of galaxies that radiate most of their power in the far-infrared (the so-called ``infrared galaxies'') contributes an important part of the whole galaxy build-up in the Universe. Since 1996, detailed (and often painful) investigations of the high-redshift infrared galaxies have resulted in the spectacular progress covered in this review. We outline the nature of the sources of the CIB including their star-formation rate, stellar and total mass, morphology, metallicity and clustering properties. We discuss their contribution to the stellar content of the Universe and their origin in the framework of the hierarchical growth of structures. We finally discuss open questions for a scenario of their evolution up to the present-day galaxies.

Guilaine Lagache; Jean-Loup Puget; Herve Dole

2005-07-12T23:59:59.000Z

286

Anisotropies in the Cosmic Microwave Background: Theory  

E-Print Network [OSTI]

Anisotropies in the Cosmic Microwave Background (CMB) contain a wealth of information about the past history of the universe and the present values of cosmological parameters. I ouline some of the theoretical advances of the last few years. In particular, I emphasize that for a wide class of cosmological models, theorists can accurately calculate the spectrum to better than a percent. The specturm of anisotropies today is directly related to the pattern of inhomogeneities present at the time of recombination. This recognition leads to a powerful argument that will enable us to distinguish inflationary models from other models of structure formation. If the inflationary models turn out to be correct, the free parameters in these models will be determined to unprecedented accuracy by the upcoming satellite missions.

Scott Dodelson

1997-02-14T23:59:59.000Z

287

The Cosmic Microwave Background and Particle Physics  

E-Print Network [OSTI]

In forthcoming years, connections between cosmology and particle physics will be made increasingly important with the advent of a new generation of cosmic microwave background (CMB) experiments. Here, we review a number of these links. Our primary focus is on new CMB tests of inflation. We explain how the inflationary predictions for the geometry of the Universe and primordial density perturbations will be tested by CMB temperature fluctuations, and how the gravitational waves predicted by inflation can be pursued with the CMB polarization. The CMB signatures of topological defects and primordial magnetic fields from cosmological phase transitions are also discussed. Furthermore, we review current and future CMB constraints on various types of dark matter (e.g. massive neutrinos, weakly interacting massive particles, axions, vacuum energy), decaying particles, the baryon asymmetry of the Universe, ultra-high-energy cosmic rays, exotic cosmological topologies, and other new physics.

Marc Kamionkowski; Arthur Kosowsky

1999-04-09T23:59:59.000Z

288

Invited Article: Characterization of background sources in space-based time-of-flight mass spectrometers  

SciTech Connect (OSTI)

For instruments that use time-of-flight techniques to measure space plasma, there are common sources of background signals that evidence themselves in the data. The background from these sources may increase the complexity of data analysis and reduce the signal-to-noise response of the instrument, thereby diminishing the science value or usefulness of the data. This paper reviews several sources of background commonly found in time-of-flight mass spectrometers and illustrates their effect in actual data using examples from ACE-SWICS and MESSENGER-FIPS. Sources include penetrating particles and radiation, UV photons, energy straggling and angular scattering, electron stimulated desorption of ions, ion-induced electron emission, accidental coincidence events, and noise signatures from instrument electronics. Data signatures of these sources are shown, as well as mitigation strategies and design considerations for future instruments.

Gilbert, J. A.; Gershman, D. J.; Gloeckler, G.; Lundgren, R. A.; Zurbuchen, T. H. [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward St, Ann Arbor, Michigan 48109 (United States); Orlando, T. M.; McLain, J. [Georgia Institute of Technology, 225 North Ave NW, Atlanta, Georgia 30332 (United States); Steiger, R. von [International Space Science Institute, Hallerstrasse 6, CH-3012 Bern, Switzerland and Physikalisches Institut, Universität Bern, Sidlerstrasse 5, CH-3012 Bern (Switzerland)

2014-09-15T23:59:59.000Z

289

Assessment of Background E. coli Levels in Runoff from Grazed & Ungrazed  

E-Print Network [OSTI]

· Three locations: · Welder Wildlife Refuge · Sinton · Chaparral-mixed grass communities · USDA

290

Determination and Mitigation of Precipitation Effects on Portal Monitor Gamma Background Levels  

E-Print Network [OSTI]

count rate with selected me- teorological parameters measured at Haifa, Israel : : : : : : : : : : : 23 II Performance of algorithm on data from selected SLD sites. : : : : : : 27 III Metrics for performance of inverse model algorithm... as they are passed through the world?s transportation infrastruc- ture. The National Nuclear Security Administration?s (NNSA) Second Line of De- fense (SLD) Initiative and its daughter project, the Megaports Initiative, represent concerted efforts to do just that...

Revis, Stephen

2012-07-16T23:59:59.000Z

291

A New Upper Limit on the Large Angular Scale Polarization of the Cosmic Microwave Background Radiation  

E-Print Network [OSTI]

, dark matter, and dark energy to the overall energy density of the universe. In addition to being of a new breed of highly-sensitive instruments that will one day map out this interesting property knowledge, Brian Keat- ing, also deserves much credit. Thanks to him I have finally memorized the radiometer

Timbie, Peter

292

Spherical Shell Cosmological Model and Uniformity of Cosmic Microwave Background Radiation  

E-Print Network [OSTI]

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.

Branislav Vlahovic

2012-07-06T23:59:59.000Z

293

SEARCH F O R LINEAR POLARIZATION O F THE COSMIC BACKGROUND 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared0 ResourceAwards SAGE Awards ,# , on behalf ofSCPDHubs+

294

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...

295

Evaluation of Background Mercury Concentrations in the SRS Groundwater System  

SciTech Connect (OSTI)

Mercury analyses associated with the A-01 Outfall have highlighted the importance of developing an understanding of mercury in the Savannah River Site groundwater system and associated surface water streams. This activity is critical based upon the fact that the EPA Ambient Water Quality Criteria (AWQC) for this constituent is 0.012mg/L, a level that is well below conventional detection limits of 0.1 to 0.2 mg/L. A first step in this process is obtained by utilizing the existing investment in groundwater mercury concentrations (20,242 records) maintained in the SRS geographical information management system (GIMS) database. Careful use of these data provides a technically defensible initial estimate for total recoverable mercury in background and contaminated SRS wells.

Looney, B.B.

1999-03-03T23:59:59.000Z

296

Holographic non-Fermi liquid in a background magnetic field  

SciTech Connect (OSTI)

We study the effects of a nonzero magnetic field on a class of 2+1 dimensional non-Fermi liquids, recently found in [Hong Liu, John McGreevy, and David Vegh, arXiv:0903.2477.] by considering properties of a Fermionic probe in an extremal AdS{sup 4} black hole background. Introducing a similar fermionic probe in a dyonic AdS{sup 4} black hole geometry, we find that the effect of a magnetic field could be incorporated in a rescaling of the probe fermion's charge. From this simple fact, we observe interesting effects like gradual disappearance of the Fermi surface and quasiparticle peaks at large magnetic fields and changes in other properties of the system. We also find Landau level like structures and oscillatory phenomena similar to the de-Haas-van Alphen effect.

Basu, Pallab; He Jianyang; Mukherjee, Anindya; Shieh, Hsien-Hang [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, B.C. V6T 1Z1 (Canada)

2010-08-15T23:59:59.000Z

297

Weighing the Universe with the Cosmic Microwave Background  

E-Print Network [OSTI]

Variations in $\\Omega$, the total density of the Universe, leave a clear and distinctive imprint on the power spectrum of temperature fluctuations in the cosmic microwave background (CMB). This signature is virtually independent of other cosmological parameters or details of particular cosmological models. We evaluate the precision with which $\\Omega$ can be determined by a CMB map as a function of sky coverage, pixel noise, and beam size. For example, assuming only that the primordial density perturbations were adiabatic and with no prior information on the values of any other cosmological parameters, a full-sky CMB map at $0.5^\\circ$ angular resolution and a noise level of $15\\,\\mu{\\rm K}$ per pixel can determine $\\Omega$ with a variance of 5\\%. If all other cosmological parameters are fixed, $\\Omega$ can be measured to better than 1\\%.

Gerard Jungman; Marc Kamionkowski; Arthur Kosowsky; David N. Spergel

1995-07-21T23:59:59.000Z

298

LArGe - Active background suppression using argon scintillation for the GERDA $0\  

E-Print Network [OSTI]

LArGe is a GERDA low-background test facility to study novel background suppression methods in a low-background environment, for future application in the GERDA experiment. Similar to GERDA, LArGe operates bare germanium detectors submersed into liquid argon (1 m$^3$, 1.4 tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to GERDA. Suppression factors of a few times $10^3$ have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12$-$4.6)$\\cdot 10^{-2}$ cts/(keV$\\cdot$kg$\\cdot$y) (90% C.L.), which is at the level of GERDA Phase I. Fu...

Agostini, M; Budjáš, D; Cattadori, C; Gangapshev, A; Gusev, K; Heisel, M; Junker, M; Klimenko, A; Lubashevskiy, A; Pelczar, K; Schönert, S; Smolnikov, A; Zuzel, G

2015-01-01T23:59:59.000Z

299

Schwarzschild black hole in dark energy background  

E-Print Network [OSTI]

In this paper we present an exact solution of Einstein's field equations describing the Schwarzschild black hole in dark energy background. It is also regarded as an embedded solution that the Schwarzschild black hole is embedded into the dark energy space producing Schwarzschild-dark energy black hole. It is found that the space-time geometry of Schwarzschild-dark energy solution is non-vacuum Petrov type $D$ in the classification of space-times. We study the energy conditions (like weak, strong and dominant conditions) for the energy-momentum tensor of the Schwarzschild-dark energy solution. We also find that the energy-momentum tensor of the Schwarzschild-dark energy solution violates the strong energy condition due to the negative pressure leading to a repulsive gravitational force of the matter field in the space-time. It is shown that the time-like vector field for an observer in the Schwarzschild-dark energy space is expanding, accelerating, shearing and non-rotating. We investigate the surface gravity and the area of the horizons for the Schwarzschild-dark energy black hole.

Ngangbam Ishwarchandra; Ng. Ibohal; K. Yugindro Singh

2014-09-27T23:59:59.000Z

300

Statistics of Cosmic Microwave Background Polarization  

E-Print Network [OSTI]

We present a formalism for analyzing a full-sky temperature and polarization map of the cosmic microwave background. Temperature maps are analyzed by expanding over the set of spherical harmonics to give multipole moments of the two-point correlation function. Polarization, which is described by a second-rank tensor, can be treated analogously by expanding in the appropriate tensor spherical harmonics. We provide expressions for the complete set of temperature and polarization multipole moments for scalar and tensor metric perturbations. Four sets of multipole moments completely describe isotropic temperature and polarization correlations; for scalar metric perturbations one set is identically zero, giving the possibility of a clean determination of the vector and tensor contributions. The variance with which the multipole moments can be measured in idealized experiments is evaluated, including the effects of detector noise, sky coverage, and beam width. Finally, we construct coordinate-independent polarization two-point correlation functions, express them in terms of the multipole moments, and derive small-angle limits.

Marc Kamionkowski; Arthur Kosowsky; Albert Stebbins

1996-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Cosmic Microwave Background Anisotropy Window Functions Revisited  

E-Print Network [OSTI]

The primary results of most observations of cosmic microwave background (CMB) anisotropy are estimates of the angular power spectrum averaged through some broad band, called band-powers. These estimates are in turn what are used to produce constraints on cosmological parameters due to all CMB observations. Essential to this estimation of cosmological parameters is the calculation of the expected band-power for a given experiment, given a theoretical power spectrum. Here we derive the "band power" window function which should be used for this calculation, and point out that it is not equivalent to the window function used to calculate the variance. This important distinction has been absent from much of the literature: the variance window function is often used as the band-power window function. We discuss the validity of this assumed equivalence, the role of window functions for experiments that constrain the power in {\\it multiple} bands, and summarize a prescription for reporting experimental results. The analysis methods detailed here are applied in a companion paper to three years of data from the Medium Scale Anisotropy Measurement.

Lloyd Knox

1999-09-28T23:59:59.000Z

302

Adsorption of acetonitrile (CH{sub 3}CN) on Si(111)-7x7 at room temperature studied by synchrotron radiation core-level spectroscopies and excited-state density functional theory calculations  

SciTech Connect (OSTI)

The room temperature adsorption of acetonitrile (CH{sub 3}-C{identical_to}N) on Si(111)-7x7 is examined by synchrotron radiation N 1s x-ray photoemission and x-ray absorption spectroscopies. The experimental spectroscopic data point to multiple adsorption geometries. Candidate structures are optimized using density functional theory (DFT), the surface being simulated by silicon clusters encompassing one (adjacent) adatom-rest atom pair. This is followed by the DFT calculation of electron transition energies and cross sections. The comparison of theoretical spectra with experimental ones indicates that the molecule is adsorbed on the surface under two forms, a nondissociated geometry (an sp{sup 2}-hybridized CN) and a dissociated one (leading to a pendent sp-hybridized CN). In the nondissociative mode, the molecule bridges an adatom-rest atom pair. For bridge-type models, the discussion of the core-excited state calculations is focussed on the so-called silicon-molecule mixed-state transitions that strongly depend on the breaking or not of the adatom backbonds and on the attachment of the nitrogen end either to the adatom or to the rest atom. Concerning the dissociated state, the CH bond cleavage leads to a cyanomethyl (Si-CH{sub 2}-CN) plus a silicon monohydride, which accounts for the spectroscopic evidence of a free C{identical_to}N group (we do not find at 300 K any spectroscopic evidence for a C{identical_to}N group datively bonded to a silicon atom via its nitrogen lone pair). Therefore the reaction products of acetonitrile on Si(111)-7x7 are similar to those detected on the Si(001)-2x1 surface at the same temperature, despite the marked differences in the reconstruction of those two surfaces, especially the distance between adjacent silicon broken bonds. In that respect, we discuss how adatom backbond breaking in the course of adsorption may explain why both surface orientations react the same way with acetonitrile.

Bournel, F.; Carniato, S.; Dufour, G.; Gallet, J.-J.; Ilakovac, V.; Rangan, S.; Rochet, F.; Sirotti, F. [Laboratoire de Chimie Physique Matiere et Rayonnement, Universite Pierre et Marie Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Synchrotron SOLEIL, L'Orme des Merisiers Saint-Aubin, Boite Postale 48, 91192 Gif sur Yvette Cedex (France)

2006-03-15T23:59:59.000Z

303

Method for detecting moisture in soils using secondary cosmic radiation  

DOE Patents [OSTI]

Water content in a soil is determined by measuring the attenuation of secondary background cosmic radiation as this radiation propagates through a layer of soil and water. By measuring the attenuation of secondary cosmic radiation in the range of 5 MeV-15 MeV it is possible to obtain a relative measure of the water content in a soil layer above a suitable radiation detector and thus establish when and how much irrigation is needed. The electronic circuitry is designed so that a battery pack can be used to supply power.

Condreva, Kenneth

2003-12-16T23:59:59.000Z

304

Solar neutrino-electron scattering as background limitation for double beta decay  

E-Print Network [OSTI]

The background on double beta decay searches due to elastic electron scattering of solar neutrinos of all double beta emitters with Q-value larger than 2 MeV is calculated, taking into account survival probability and flux uncertainties of solar neutrinos. This work determines the background level to be [1-2]E-7 counts /keV/kg/yr, depending on the precise Q-value of the double beta emitter. It is also shown that the background level increases dramatically if going to lower Q-values. Furthermore, studies are done for various detector systems under consideration for next generation experiments. It was found that experiments based on loaded liquid scintillator have to expect a higher background. Within the given nuclear matrix element uncertainties any approach exploring the normal hierarchy has to face this irreducible background, which is a limitation on the minimal achievable background for purely calorimetric approaches. Large scale liquid scintillator experiments might encounter this problem already while exploring the inverted hierarchy. Potential caveats by using more sophisticated experimental setups are also discussed.

N. F. de Barros; K. Zuber

2011-09-16T23:59:59.000Z

305

Cosmological-Parameter Determination with Microwave Background Maps  

E-Print Network [OSTI]

The angular power spectrum of the cosmic microwave background (CMB) contains information on virtually all cosmological parameters of interest, including the geometry of the Universe ($\\Omega$), the baryon density, the Hubble constant ($h$), the cosmological constant ($\\Lambda$), the number of light neutrinos, the ionization history, and the amplitudes and spectral indices of the primordial scalar and tensor perturbation spectra. We review the imprint of each parameter on the CMB. Assuming only that the primordial perturbations were adiabatic, we use a covariance-matrix approach to estimate the precision with which these parameters can be determined by a CMB temperature map as a function of the fraction of sky mapped, the level of pixel noise, and the angular resolution. For example, with no prior information about any of the cosmological parameters, a full-sky CMB map with $0.5^\\circ$ angular resolution and a noise level of 15 $\\mu$K per pixel can determine $\\Omega$, $h$, and $\\Lambda$ with standard errors of $\\pm0.1$ or better, and provide determinations of other parameters which are inaccessible with traditional observations. Smaller beam sizes or prior information on some of the other parameters from other observations improves the sensitivity. The dependence on the the underlying cosmological model is discussed.

Gerard Jungman; Marc Kamionkowski; Arthur Kosowsky; David N. Spergel

1996-05-23T23:59:59.000Z

306

Multiple concentric annuli for characterizing spatially nonuniform backgrounds  

E-Print Network [OSTI]

A method is presented for estimating the background at a given location on a sky map by interpolating the estimated background from a set of concentric annuli which surround this location. If the background is nonuniform but smoothly varying, this method provides a more accurate (though less precise) estimate than can be obtained with a single annulus. Several applications of multi-annulus background estimation are discussed, including direct testing for point sources in the presence of a nonuniform background, the generation of "surrogate maps" for characterizing false alarm rates, and precise testing of the null hypothesis that the background is uniform.

James Theiler; Jeff Bloch

1999-01-26T23:59:59.000Z

307

Environmental radiation detection via thermoluminescence  

DOE Patents [OSTI]

The method and apparatus of the present invention relate to cryogenically cooling a thermoluminescent material, exposing it to a low level of radiation (less than about 1 R) while it is at the cooled temperature, warming the thermoluminescent material to room temperature'' and counting the photons emitted during heating. Sufficient sensitivity is achieved without exposing the thermoluminescent material to ultraviolet light thereby simplifying the measurements.

Miller, S.D.

1993-03-23T23:59:59.000Z

308

Radiation-hardened polymeric films  

DOE Patents [OSTI]

The radiation-induced conductivity of polymeric dielectrics with low electronic mobility is reduced by doping with electron donor or electron acceptor compounds at a level of 10/sup 15/ to 10/sup 21/ molecules of dopant/cm/sup 3/. Polyesters, polyolefins, perfluoropolyolefins, vinyl polymers, vinylidene polymers, polycarbonates, polysulfones and polyimides can benefit from such a treatment. Usable dopants include 2,4,7-trinitro-9-fluorenone, tetracyanethylene, 7,7,8,8-tetracyanoquinodimethane, m-dinitrobenzene, 2-isopropylcarbazole, and triphenylamine.

Arnold, C. Jr.; Hughes, R.C.; Kepler, R.G.; Kurtz, S.R.

1984-07-16T23:59:59.000Z

309

Radiation-hardened polymeric films  

DOE Patents [OSTI]

The radiation-induced conductivity of polymeric dielectrics with low electronic mobility is reduced by doping with electron donor or electron acceptor compounds at a level of 10.sup.15 to 10.sup.21 molecules of dopant/cm.sup.3. Polyesters, polyolefins, perfluoropolyolefins, vinyl polymers, vinylidene polymers, polycarbonates, polysulfones and polyimides can benefit from such a treatment. Usable dopants include 2,4,7-trinitro-9-fluorenone, tetracyanethylene, 7,7,8,8-tetracyanoquinodimethane, m-dinitrobenzene, 2-isopropylcarbazole, and triphenylamine.

Arnold, Jr., Charles (Albuquerque, NM); Hughes, Robert C. (Albuquerque, NM); Kepler, R. Glen (Albuquerque, NM); Kurtz, Steven R. (Albuquerque, NM)

1986-01-01T23:59:59.000Z

310

Radiation-dominated area metric cosmology  

E-Print Network [OSTI]

We provide further crucial support for a refined, area metric structure of spacetime. Based on the solution of conceptual issues, such as the consistent coupling of fermions and the covariant identification of radiation fields on area metric backgrounds, we show that the radiation-dominated epoch of area metric cosmology is equivalent to that epoch in standard Einstein cosmology. This ensures, in particular, successful nucleosynthesis. This surprising result complements the previously derived prediction of a small late-time acceleration of an area metric universe.

Frederic P. Schuller; Mattias N. R. Wohlfarth

2007-06-12T23:59:59.000Z

311

Project plan for the background soils project for the Paducah Gaseous Diffusion Plant, Paducah, Kentucky  

SciTech Connect (OSTI)

The Background Soils Project for the Paducah Gaseous Diffusion Plant (BSPP) will determine the background concentration levels of selected naturally occurring metals, other inorganics, and radionuclides in soils from uncontaminated areas in proximity to the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky. The data will be used for comparison with characterization and compliance data for soils, with significant differences being indicative of contamination. All data collected as part of this project will be in addition to other background databases established for the PGDP. The BSPP will address the variability of surface and near-surface concentration levels with respect to (1) soil taxonomical types (series) and (2) soil sampling depths within a specific soil profile. The BSPP will also address the variability of concentration levels in deeper geologic formations by collecting samples of geologic materials. The BSPP will establish a database, with recommendations on how to use the data for contaminated site assessment, and provide data to estimate the potential human and health and ecological risk associated with background level concentrations of potentially hazardous constituents. BSPP data will be used or applied as follows.

NONE

1995-09-01T23:59:59.000Z

312

Passive background correction method for spatially resolved detection  

DOE Patents [OSTI]

A method for passive background correction during spatially or angularly resolved detection of emission that is based on the simultaneous acquisition of both the passive background spectrum and the spectrum of the target of interest.

Schmitt, Randal L. (Tijeras, NM); Hargis, Jr., Philip J. (Albuquerque, NM)

2011-05-10T23:59:59.000Z

313

Uniform Gauge for D1-brane in General Background  

E-Print Network [OSTI]

We construct uniform gauge D1-brane action in general background. We also discuss how this action transforms under double Wick rotation and determine transformation properties of background fields.

Kluson, J

2015-01-01T23:59:59.000Z

314

MARSAME Appendix B B. SOURCES OF BACKGROUND RADIOACTIVITY  

E-Print Network [OSTI]

: · The Nuclear Regulatory Commission (NRC) provides information concerning background radioactivity in Background as a Residual Radioactivity Criterion for Decommissioning NUREG-1501 (NRC 1994). · The United Nations Scientific

315

Muon-induced backgrounds in the CUORICINO experiment  

E-Print Network [OSTI]

background in the neutrinoless double beta decay region ofis searching for neutrinoless double beta decay (0???), a

Andreotti, E.

2010-01-01T23:59:59.000Z

316

Evidence-Based Background Material Underlying Guidance for Federal...  

Broader source: Energy.gov (indexed) [DOE]

Material Underlying Guidance for Federal Agencies in Implementing Strategic Sustainability Performance Plans Evidence-Based Background Material Underlying Guidance for...

317

Surface-wave-enabled darkfield aperture for background suppression during  

E-Print Network [OSTI]

can be directly incorporated onto optical sensors to accom- plish predetection background suppression if the sensor is fully capable of measuring the same weak signal in the absence of background (1, 2- trivial to employ. A sensor that can intrinsically cancel a strong background prior to signal detection

Yang, Changhuei

318

Plutonium radiation surrogate  

DOE Patents [OSTI]

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.

Frank, Michael I. (Dublin, CA)

2010-02-02T23:59:59.000Z

319

Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry  

SciTech Connect (OSTI)

The measurement of naturally occurring low level radioactivity background in a high voltage (HV) cable by high resolution inductively coupled plasma mass spectrometry (HR ICP MS) is presented in this work. The measurements were performed at the Chemistry Service of the Gran Sasso National Laboratory. The contributions to the radioactive background coming from the different components of the heterogeneous material were separated. Based on the mass fraction of the cable, the whole contamination was calculated. The HR ICP MS results were cross-checked by gamma ray spectroscopy analysis that was performed at the low background facility STELLA (Sub Terranean Low Level Assay) of the LNGS underground lab using HPGe detectors.

Vacri, M. L. di; Nisi, S.; Balata, M. [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)] [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)

2013-08-08T23:59:59.000Z

320

Measurement of Radiation Damage on Silica Aerogel Cerenkov Radiator  

E-Print Network [OSTI]

We measured the radiation damage on silica aerogel Cerenkov radiators originally developed for the B-factory experiment at KEK. Refractive index of the aerogel samples ranged from 1.012 to 1.028. The samples were irradiated up to 9.8 MRad of equivalent dose. Measurements of transmittance and refractive index were carried out and these samples were found to be radiation hard. Deteriorations in transparency and changes of refractive index were observed to be less than 1.3% and 0.001 at 90% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed. 1 Introduction Silica aerogels(aerogels) are a colloidal form of glass, in which globules of silica are connected in three dimensional networks with siloxan bonds. They are solid, very light, transparent and their refractive index can be controlled in the production process. Many high energy and nuclear physics experiments have used aerogels instead of pressurized gas for their Cerenkov coun...

Belle Preprint; Sahu Wang; M. Z. Wang; R. Suda; R. Enomoto; K. C. Peng; C. H. Wang; I. Adachi; M. Amami

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Gravitational Radiation and Very Long Baseline Interferometry  

E-Print Network [OSTI]

Gravitational waves affect the observed direction of light from distant sources. At telescopes, this change in direction appears as periodic variations in the apparent positions of these sources on the sky; that is, as proper motion. A wave of a given phase, traveling in a given direction, produces a characteristic pattern of proper motions over the sky. Comparison of observed proper motions with this pattern serves to test for the presence of gravitational waves. A stochastic background of waves induces apparent proper motions with specific statistical properties, and so, may also be sought. In this paper we consider the effects of a cosmological background of gravitational radiation on astrometric observations. We derive an equation for the time delay measured by two antennae observing the same source in an Einstein-de Sitter spacetime containing gravitational radiation. We also show how to obtain similar expressions for curved Friedmann-Robertson-Walker spacetimes.

Ted Pyne; Carl R. Gwinn; Mark Birkinshaw; T. Marshall Eubanks; Demetrios N. Matsakis

1995-07-10T23:59:59.000Z

322

Radiator Labs | Department of Energy  

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

of steam buildings. Radiator Labs developed a mechanism that allows heating systems to control heat transfer at each radiator. The Radiator Labs design utilizes an...

323

The universal radiative transport equation  

E-Print Network [OSTI]

THE UNIVERSAL RADIATIVE TRANSPORT EQUATION Rudolph W.The Universal Radiative Transport Equation Rudolph W.The various radiative transport equations used in general

Preisendorfer, Rudolph W

1959-01-01T23:59:59.000Z

324

Tachyons and Gravitational Cherenkov Radiation  

E-Print Network [OSTI]

AND GRAVITATIONAL CHERENKOV RADIATION CHARLES SCHWARTZwould emit gravitational radiation. It is very small.gravitational waves; Cherenkov radiation. In a recent work,

Schwartz, Charles

2011-01-01T23:59:59.000Z

325

Radiation Safety Program Annual Review  

E-Print Network [OSTI]

........................................................................10 AREA RADIATION SURVEYS AND CONTAMINATION CONTROL...........................................11.....................................................................................................13 RADIOACTIVE WASTE MANAGEMENT meetings of the Radiation Safety Committee where new users and uses of radioactive materials, radiation

Lyubomirsky, Ilya

326

Cosmological Rotation of Quantum-Mechanical Origin and Anisotropy of the Microwave Background  

E-Print Network [OSTI]

It is shown that rotational cosmological perturbations can be generated in the early Universe, similarly to gravitational waves. The generating mechanism is quantum-mechanical in its nature, and the created perturbations should now be placed in squeezed vacuum quantum states. The physical conditions under which the phenomenon can occur are formulated. The generated perturbations can contribute to the large-angular-scale anisotropy of the cosmic microwave background radiation. An exact formula is derived for the angular correlation function of the temperature variations caused by the quantum-mechanically generated rotational perturbations. The multipole expansion begins from the dipole component. The comparison with the case of gravitational waves is made.

L. P. Grishchuk

1993-10-06T23:59:59.000Z

327

MaGe - a Geant4-based Monte Carlo framework for low-background experiments  

E-Print Network [OSTI]

A Monte Carlo framework, MaGe, has been developed based on the Geant4 simulation toolkit. Its purpose is to simulate physics processes in low-energy and low-background radiation detectors, specifically for the Majorana and Gerda $^{76}$Ge neutrinoless double-beta decay experiments. This jointly-developed tool is also used to verify the simulation of physics processes relevant to other low-background experiments in Geant4. The MaGe framework contains simulations of prototype experiments and test stands, and is easily extended to incorporate new geometries and configurations while still using the same verified physics processes, tunings, and code framework. This reduces duplication of efforts and improves the robustness of and confidence in the simulation output.

Yuen-Dat Chan; Jason A. Detwiler; Reyco Henning; Victor M. Gehman; Rob A. Johnson; David V. Jordan; Kareem Kazkaz; Markus Knapp; Kevin Kroninger; Daniel Lenz; Jing Liu; Xiang Liu; Michael G. Marino; Akbar Mokhtarani; Luciano Pandola; Alexis G. Schubert; Claudia Tomei

2008-02-06T23:59:59.000Z

328

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...

329

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...

330

Measurement of Neutron Background at the Pyhasalmi mine for CUPP Project, Finland  

E-Print Network [OSTI]

A natural neutron flux is one of significant kind of background in high-sensitive underground experiments. Therefore, when scheduling a delicate underground measurements one needs to measure neutron background. Deep underground the most significant source of neutrons are the U-Th natural radioactive chains giving a fission spectrum with the temperature of 2-3 MeV. Another source is the U-Th alpha-reactions on light nuclei of mine rock giving neutrons with different spectra in the 1-15 MeV energy region. Normal basalt mine rocks contain 1 ppm g/g of U-238 and less. Deep underground those rocks produce natural neutron fluxes of 10^{-7} - 10^{-6} cm^{-2}s^{-1} above 1 MeV. To measure such a background one needs a special techniques. In the Institute for Nuclear Research, Moscow, the neutron spectrometer was developed and built which is sensitive to such a low neutron fluxes. At the end of 2001 the collection of neutron data at the Pyhasalmi mine was started for the CUPP project. During 2002 the background and rough energy spectra of neutron at underground levels 410, 660, 990 and 1410 m were measured. The result of the measurement of the neutron background at different levels of the Pyhasalmi mine is presented and discussed. Data analysis is performed in different energy ranges from thermal neutrons up to 25 MeV and above.

J. N. Abdurashitov; V. N. Gavrin; V. L. Matushko; A. A. Shikhin; V. E. Yants; J. Peltoniemi; T. Keranen

2006-07-20T23:59:59.000Z

331

Astroparticle Physics with a Customized Low-Background Broad Energy Germanium Detector  

E-Print Network [OSTI]

The MAJORANA Collaboration is building the MAJORANA DEMONSTRATOR, a 60 kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in Lead, SD. The MAJORANA DEMONSTRATOR will search for neutrinoless double-beta decay of 76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 1-10 GeV/c^2 mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the MAJORANA Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment.

MAJORANA Collaboration; C. E. Aalseth; M. Amman; F. T. Avignone III; H. O. Back; A. S. Barabash; P. S. Barbeau; M. Bergevin; F. E. Bertrand; M. Boswell; V. Brudanin; W. Bugg; T. H. Burritt; M. Busch; G. Capps; Y-D. Chan; J. I. Collar; R. J. Cooper; R. Creswick; J. A. Detwiler; J. Diaz; P. J. Doe; Yu. Efremenko; V. Egorov; H. Ejiri; S. R. Elliott; J. Ely; J. Esterline; H. Farach; J. E. Fast; N. Fields; P. Finnerty; B. Fujikawa; E. Fuller; V. M. Gehman; G. K. Giovanetti; V. E. Guiseppe; K. Gusey; A. L. Hallin; G. C Harper; R. Hazama; R. Henning; A. Hime; E. W. Hoppe; T. W. Hossbach; M. A. Howe; R. A. Johnson; K. J. Keeter; M. Keillor; C. Keller; J. D. Kephart; M. F. Kidd; A. Knecht; O. Kochetov; S. I. Konovalov; R. T. Kouzes; L. Leviner; J. C. Loach; P. N. Luke; S. MacMullin; M. G. Marino; R. D. Martin; D. -M. Mei; H. S. Miley; M. L. Miller; L. Mizouni; A. W. Meyers; M. Nomachi; J. L. Orrell; D. Peterson; D. G. Phillips II; A. W. P. Poon; G. Prior; J. Qian; D. C. Radford; K. Rielage; R. G. H. Robertson; L. Rodriguez; K. P. Rykaczewski; H. Salazar; A. G. Schubert; T. Shima; M. Shirchenko; D. Steele; J. Strain; G. Swift; K. Thomas; V. Timkin; W. Tornow; T. D. Van Wechel; I. Vanyushin; R. L. Varner; K. Vetter; J. F. Wilkerson; B. A. Wolfe; W. Xiang; E. Yakushev; H. Yaver; A. R. Young; C. -H. Yu; V. Yumatov; C. Zhang; S. Zimmerman

2010-07-20T23:59:59.000Z

332

Astroparticle physics with a customized low-background broad energy Germanium detector  

SciTech Connect (OSTI)

The Majorana Collaboration is building the Majorana Demonstrator, a 60 kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in Lead, SD. The Majorana Demonstrator will search for neutrinoless double-beta decay of 76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 1-10 GeV/c{sup 2} mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the Majorana Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment.

Aalseth, Craig E.; Amman, M.; Avignone, Frank T.; Back, Henning O.; Barabash, Alexander S.; Barbeau, P. S.; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Bugg, William; Burritt, Tom H.; Busch, Matthew; Capps, Greg L.; Chan, Yuen-Dat; Collar, J. I.; Cooper, R. J.; Creswick, R.; Detwiler, Jason A.; Diaz, J.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, Steven R.; Ely, James H.; Esterline, James H.; Farach, H. A.; Fast, James E.; Fields, N.; Finnerty, P.; Fujikawa, Brian; Fuller, Erin S.; Gehman, Victor M.; Giovanetti, G. K.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Harper, Gregory; Hazama, R.; Henning, Reyco; Hime, Andrew; Hoppe, Eric W.; Hossbach, Todd W.; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keillor, Martin E.; Keller, C.; Kephart, Jeremy D.; Kidd, Mary; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; Leviner, L.; Loach, J. C.; Luke, P.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Mei, Dong-Ming; Miley, Harry S.; Miller, M. L.; Mizouni, Leila; Myers, Allan W.; Nomachi, Masaharu; Orrell, John L.; Peterson, David; Phillips, D.; Poon, Alan; Prior, Gersende; Qian, J.; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Rodriguez, Larry; Rykaczewski, Krzysztof P.; Salazar, Harold; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Steele, David; Strain, J.; Swift, Gary; Thomas, K.; Timkin, V.; Tornow, W.; Van Wechel, T. D.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Wilkerson, J. F.; Wolfe, B. A.; Xiang, W.; Yakushev, E.; Yaver, Harold; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir; Zhang, C.; Zimmerman, S.

2011-10-01T23:59:59.000Z

333

Evaluation of Breast Sentinel Lymph Node Coverage by Standard Radiation Therapy Fields  

SciTech Connect (OSTI)

Background: Biopsy of the breast sentinel lymph node (SLN) is now a standard staging procedure for early-stage invasive breast cancer. The anatomic location of the breast SLN and its relationship to standard radiation fields has not been described. Methods and Materials: A retrospective review of radiotherapy treatment planning data sets was performed in patients with breast cancer who had undergone SLN biopsy, and those with a surgical clip at the SLN biopsy site were identified. The location of the clip was evaluated relative to vertebral body level on an anterior-posterior digitally reconstructed radiograph, treated whole-breast tangential radiation fields, and standard axillary fields in 106 data sets meeting these criteria. Results: The breast SLN varied in vertebral body level position, ranging from T2 to T7 but most commonly opposite T4. The SLN clip was located below the base of the clavicle in 90%, and hence would be excluded from standard axillary radiotherapy fields where the inferior border is placed at this level. The clip was within the irradiated whole-breast tangent fields in 78%, beneath the superior-posterior corner multileaf collimators in 12%, and outside the tangent field borders in 10%. Conclusions: Standard axillary fields do not encompass the lymph nodes at highest risk of containing tumor in breast cancer patients. Elimination of the superior-posterior corner MLCs from the tangent field design would result in inclusion of the breast SLN in 90% of patients treated with standard whole-breast irradiation.

Rabinovitch, Rachel [Department of Radiation Oncology, University of Colorado Cancer Center, Aurora, CO (United States)], E-mail: Rachel.rabinovitch@uchsc.edu; Ballonoff, Ari; Newman, Francis M.S. [Department of Radiation Oncology, University of Colorado Cancer Center, Aurora, CO (United States); Finlayson, Christina [Department of GI, Tumor, and Endocrine Surgery, University of Colorado Cancer Center, Aurora, CO (United States)

2008-04-01T23:59:59.000Z

334

RADIONUCLIDE RADIATION PROTECTION  

E-Print Network [OSTI]

COPYRIGHT 2002 Nuclear Technology Publishing #12;3 #12;4 #12;5 Radiation Protection Dosimetry Vol. 98, No'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

Healy, Kevin Edward

335

Radiation Damping with Inhomogeneous  

E-Print Network [OSTI]

Radiation Damping with Inhomogeneous Broadening: Limitations of the Single Bloch Vector Model of inhomoge- neous broadening on radiation damping of free precession signals have been described using 13: 1 7, 2001 KEY WORDS: radiation damping; FID shape; inhomogeneous broadening The phenomenon

Augustine, Mathew P.

336

astroph/9507030 Gravitational Radiation  

E-Print Network [OSTI]

astro­ph/9507030 10 Jul 95 Gravitational Radiation and Very Long Baseline Interferometry Ted Pyne of gravitational radiation on astrometric observations. We derive an equation for the time delay measured by two antennae observing the same source in an Einstein­de Sitter spacetime containing gravitational radiation

Fygenson, Deborah Kuchnir

337

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

338

Design/installation and structural integrity assessment under the Federal Facility Agreement for Bethel Valley low-level waste collection and transfer system upgrade for Building 2026 (High Radiation Level Analytical Laboratory) and Building 2099 (Monitoring and Control Station) at Oak Ridge National Laboratory  

SciTech Connect (OSTI)

This document presents a Design/Installation and Structural Integrity Assessment for a replacement tank system for portions of the Bethel Valley Low-Level Waste (LLW) System, located at the Oak Ridge Reservation, Oak Ridge, Tennessee. This issue of the assessment covers the design aspects of the replacement tank system, and certifies that the design has sufficient structural integrity and is acceptable for the storing or treating of hazardous and/or radioactive substances. This document will be reissued at a future date and will then include the assessment of the installation of the replacement tank system. The present issue identifies specific activities that must be completed during the fabrication, installation, and testing of the replacement tank system in order to provide assurance that the final installation complies with governing requirements.

Not Available

1994-11-01T23:59:59.000Z

339

Electric Dipole Radiation from Spinning Dust Grains  

E-Print Network [OSTI]

We discuss the rotational excitation of small interstellar grains and the resulting electric dipole radiation from spinning dust. Attention is given to excitation and damping of rotation by: collisions with neutrals; collisions with ions; plasma drag; emission of infrared radiation; emission of microwave radiation; photoelectric emission; and formation of H_2 on the grain surface. We introduce dimensionless functions F and G which allow direct comparison of the contributions of different mechanisms to rotational drag and excitation. Emissivities are estimated for dust in different phases of the interstellar medium, including diffuse HI, warm HI, low-density photoionized gas, and cold molecular gas. Spinning dust grains can explain much, and perhaps all, of the 14-50 GHz background component recently observed in CBR studies. It should be possible to detect rotational emission from small grains by ground-based observations of molecular clouds.

B. T. Draine; A. Lazarian

1998-02-18T23:59:59.000Z

340

Low Background Gamma-Ray Spectrometry in the 'Laboratoire Souterrain de Modane'  

SciTech Connect (OSTI)

Most of the underground experiments in physics and many studies in geology, biology or environmental sciences face a common requirement with the necessity of using experimental devices with ultra-low background radioactivity. Many developments involving many different techniques have been used in order to be able to measure extremely low levels of radioactivity in materials. This report will focus on low background gamma-ray spectrometry and will describe the work which has been carried out over the last fifteen years in the 'Laboratoire Souterrain de Modane' (LSM)

Hubert, Ph.; Hubert, F. [Centre d'Etudes Nucleaires de Bordeaux Gradignan, BP 120, Le Haut Vigneau, 33175 Gradignan Cedex (France)

2007-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

The MAJORANA experiment: an ultra-low background search for neutrinoless double-beta decay  

SciTech Connect (OSTI)

The observation of neutrinoless double-beta decay would resolve the Majorana nature of the neutrino and could provide information on the absolute scale of the neutrino mass. The initial phase of the Majorana Experiment, known as the Demonstrator, will house 40 kg of Ge in an ultra-low background shielded environment at the 4850' level of the Sanford Underground Laboratory in Lead, SD. The objective of the Demonstrator is to validate whether a future 1-tonne experiment can achieve a background goal of one count per tonne-year in a narrow region of interest around the 76Ge neutrinoless double-beta decay peak.

Phillips, D.; Aguayo Navarrete, Estanislao; Avignone, Frank T.; Back, Henning O.; Barabash, Alexander S.; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Collar, J. I.; Combs, Dustin C.; Cooper, R. J.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, Steven R.; Esterline, James H.; Fast, James E.; Fields, N.; Finnerty, P.; Fraenkle, Florian; Gehman, Victor; Giovanetti, G. K.; Green, Matthew P.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Hazama, R.; Henning, Reyco; Hime, Andrew; Hoppe, Eric W.; Horton, Mark; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keller, C.; Kidd, Mary; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaFerriere, Brian D.; LaRoque, B. H.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Mei, Dong-Ming; Merriman, Jason H.; Miller, M. L.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; Overman, Nicole R.; Poon, Alan; Perumpilly, Gopakumar; Prior, Gersende; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Steele, David; Strain, J.; Thomas, K.; Timkin, V.; Tornow, W.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, J. F.; Wolfe, B. A.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir; Zhang, C.

2012-12-01T23:59:59.000Z

342

NRC TLD Direct Radiation Monitoring Network. Progress report, July--September 1993: Volume 13, No. 3  

SciTech Connect (OSTI)

This report provides the status and results of the NRC Thermoluminescent Dosimeter (TLD) Direct Radiation Monitoring Network. It presents the radiation levels measured in the vicinity of NRC licensed facilities throughout the country for the third quarter of 1993.

Struckmeyer, R.

1993-11-01T23:59:59.000Z

343

E-Print Network 3.0 - antibody-targeted radiation cancer Sample...  

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

is an increased risk of cancer. The amount of risk depends on the amount of radiation dose... low-level radiation exposure increases one's risk of cancer, medical studies have...

344

ME 361F Radiation and Radiation Protection Laboratory ABET EC2000 syllabus  

E-Print Network [OSTI]

-Ray Spectrometry 5. Gamma Ray Shielding/Low Level Counting 6. Neutron Activation Analysis 7. Sodium Iodide Detector-Ray Attenuation · Low-Level Gamma Ray Spectrometry · Reactor Health Physics · Neutron Shielding · Sodium Iodide and laboratory topics include personnel monitoring, radiation detection systems, gamma-ray spectroscopy

Ben-Yakar, Adela

345

Radiation Shielding and Radiological Protection  

E-Print Network [OSTI]

Radiation Shielding and Radiological Protection J. Kenneth Shultis Richard E. Faw Department@triad.rr.com Radiation Fields and Sources ................................................ . Radiation Field Variables........................................................... .. Direction and Solid Angle Conventions ......................................... .. Radiation Fluence

Shultis, J. Kenneth

346

TERSat: Trapped Energetic Radiation Satellite  

E-Print Network [OSTI]

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

Clements, Emily B.

2012-01-01T23:59:59.000Z

347

Radiative MHD simulation of sunspot structure  

E-Print Network [OSTI]

Results of a 3D MHD simulation of a sunspot with a photospheric size of about 20 Mm are presented. The simulation has been carried out with the MURaM code, which includes a realistic equation of state with partial ionization and radiative transfer along many ray directions. The largely relaxed state of the sunspot shows a division in a central dark umbral region with bright dots and a penumbra showing bright filaments of about 2 to 3 Mm length with central dark lanes. By a process similar to the formation of umbral dots, the penumbral filaments result from magneto-convection in the form of upflow plumes, which become elongated by the presence of an inclined magnetic field: the upflow is deflected in the outward direction while the magnetic field is weakened and becomes almost horizontal in the upper part of the plume near the level of optical depth unity. A dark lane forms owing to the piling up of matter near the cusp-shaped top of the rising plume that leads to an upward bulging of the surfaces of constant optical depth. The simulated penumbral structure corresponds well to the observationally inferred interlocking-comb structure of the magnetic field with Evershed outflows along dark-laned filaments with nearly horizontal magnetic field and overturning perpendicular (`twisting') motion, which are embedded in a background of stronger and less inclined field. Photospheric spectral lines are formed at the very top and somewhat above the upflow plumes, so that they do not fully sense the strong flow as well as the large field inclination and significant field strength reduction in the upper part of the plume structures.

M. Rempel; M. Schuessler; M. Knoelker

2008-09-30T23:59:59.000Z

348

The Structure and Evolution of Stars Recommended Background Reading  

E-Print Network [OSTI]

S dt , (3) Energy Transport (Radiative Diffusion Equation): Lr = -4r2 4ac 3 T3 dT dr , (4) Energy determined by the mechanisms by which energy is transported from the core to the surface, radiation, convec- tion, conduction (energy transport equation); · the central temperature is determined

Mojzsis, Stephen J.

349

Radiation Related Terms Basic Terms  

E-Print Network [OSTI]

Radiation Related Terms Basic Terms Radiation Radiation is energy in transit in the form of high not carry enough energy to separate molecules or remove electrons from atoms. Ionizing radiation Ionizing radiation is radiation with enough energy so that during an interaction with an atom, it can remove tightly

Vallino, Joseph J.

350

Radiation Detection Computational Benchmark Scenarios  

SciTech Connect (OSTI)

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.

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

2013-09-24T23:59:59.000Z

351

LOW-LEVEL RADIATION HEALTH EFFECTS: PROGRAMS AND PANEL DISCUSSION  

E-Print Network [OSTI]

accident. The report of the Soviet Union to the International Atomic Energy Agency experts' meeting plutonium had been produced in reactors and separated for bomb production for -40 yr (Ref. 1. The reduction was presumably due to the reduced effects at low dose rate. THE DATA SETS In the former USSR

Shlyakhter, Ilya

352

P ORNiiTM-7004 Results of Ground Level Radiation  

Office of Legacy Management (LM)

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofof EnergyYou$0.C. 20545*.MSE Cores" _August.. .._ . . -mN

353

Backgrounds and Projected Limits from Dark Matter Direct Detection Experiments  

E-Print Network [OSTI]

A simple formula is introduced which indicates the amount by which projections of dark matter direct detection experiments are expected to be degraded due to backgrounds.

Scott Dodelson

2008-12-08T23:59:59.000Z

354

accelerator related backgrounds: Topics by E-print Network  

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

the first years... Drozhdin, A I; Mokhov, N V 1996-01-01 2 Cosmic acceleration without dark energy: Background tests and thermodynamic analysis General Relativity & Quantum...

355

The Hawking Temperature in the context of Dark Energy for Reissner-Nordstrom and Kerr background  

E-Print Network [OSTI]

For emergent gravity metrics, presence of dark energy modifies the Hawking temperature. We show that for the spherically symmetric Reissner-Nordstrom (RN) background metric, the emergent metric can be mapped into a Robinson-Trautman blackhole. Allowed values of the dark energy density follow from rather general conditions. For some allowed value of the dark energy density this blackhole can have zero Hawking temperature i.e. the blackhole does not radiate. For a Kerr background along $\\theta=0$, the emergent blackhole metric satisfies Einstein's equations for large $r$ and always radiates. Our analysis is done in the context of emergent gravity metrics having $k-$essence scalar fields $\\phi$ with a Born-Infeld type lagrangian. In both cases the scalar field $\\phi(r,t)=\\phi_{1}(r)+\\phi_{2}(t)$ also satisfies the emergent gravity equations of motion for $r\\rightarrow\\infty$ and $\\theta=0$. \\keywords{dark energy, k-essence, Reissner-Nordstrom and Kerr blackholes} \\pacs{98.80.-k ;95.36.+x}

Goutam Manna; Debashis Gangopadhyay

2014-03-17T23:59:59.000Z

356

A Polarization Sensitive Bolometric Detector for Observations of the Cosmic Microwave Background  

E-Print Network [OSTI]

We have developed a bolometric detector that is intrinsically sensitive to linear polarization which is optimized for making measurements of the polarization of the cosmic microwave background radiation. The receiver consists of a pair of co-located silicon nitride micromesh absorbers which couple anisotropically to linearly polarized radiation through a corrugated waveguide structure. This system allows simultaneous background limited measurements of the Stokes I and Q parameters over ~ 30% bandwidths at frequencies from ~ 60 to 600 GHz. Since both linear polarizations traverse identical optical paths from the sky to the point of detection, the susceptibility to systematic effects is minimized. The amount of uncorrelated noise between the two polarization senses is limited to the quantum limit of thermal and photon shot noise, while drifts in the relative responsivity to orthogonal polarizations are limited to the effect of non-uniformity in the thin film deposition of the leads and the intrinsic thermistor properties. Devices using NTD Ge thermistors have achieved NEPs of 2 x 10^{-17} W/sqrt{Hz} with a 1/f knee below 100 mHz at a base temperature of 270 mK. Numerical modelling of the structures has been used to optimize the bolometer geometry and coupling to optics. Comparisons of numerical results and experimental data are made. A description of how the quantities measured by the device can be interpreted in terms of the Stokes parameters is presented. The receiver developed for the Boomerang and Planck HFI focal planes is presented in detail.

W. C. Jones; R. S. Bhatia; J. J. Bock; A. E. Lange

2002-09-08T23:59:59.000Z

357

Space charge dosimeters for extremely low power measurements of radiation in shipping containers  

DOE Patents [OSTI]

Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes insitu polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

Britton, Jr., Charles L. (Alcoa, TN); Buckner, Mark A. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Bryan, William L. (Knoxville, TN)

2011-05-03T23:59:59.000Z

358

Space charge dosimeters for extremely low power measurements of radiation in shipping containers  

DOE Patents [OSTI]

Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes in situ polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

Britton, Jr.; Charles L. (Alcoa, TN); Buckner, Mark A. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Bryan, William L. (Knoxville, TN)

2011-04-26T23:59:59.000Z

359

Alpha-beta radiation detector  

DOE Patents [OSTI]

The invention is based in part on the discovery that a plastic housing that is lightweight is surprisingly efficient inasmuch as background signals from any gamma radiation are significantly reduced by using a plastic housing instead of a metal housing. A further aspect of the present invention is the profile of the housing as a bi-linear approximation to a parabola resulting in full optical response from any location on the scintillation material to the photomultiplier tube. A yet further aspect of the present invention is that the survey probe is resistant to magnetic fields. A yet further aspect of the present invention is the use of a snap-fit retaining bracket that overcomes the need for multiple screws.

Fleming, Dale M. (Richland, WA); Simmons, Kevin L. (Kennewick, WA); Froelich, Thomas J. (West Richland, WA); Carter, Gregory L. (Richland, WA)

1998-01-01T23:59:59.000Z

360

Alpha-beta radiation detector  

DOE Patents [OSTI]

The invention is based in part on the discovery that a plastic housing that is lightweight is surprisingly efficient inasmuch as background signals from any gamma radiation are significantly reduced by using a plastic housing instead of a metal housing. A further aspect of the present invention is the profile of the housing as a bi-linear approximation to a parabola resulting in full optical response from any location on the scintillation material to the photomultiplier tube. A yet further aspect of the present invention is that the survey probe is resistant to magnetic fields. A yet further aspect of the present invention is the use of a snap-fit retaining bracket that overcomes the need for multiple screws. 16 figs.

Fleming, D.M.; Simmons, K.L.; Froelich, T.J.; Carter, G.L.

1998-08-18T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Radiation-Dominated Disks Are Thermally Stable  

E-Print Network [OSTI]

When the accretion rate is more than a small fraction of Eddington, the inner regions of accretion disks around black holes are expected to be radiation-dominated. However, in the alpha-model, these regions are also expected to be thermally unstable. In this paper, we report two 3-d radiation MHD simulations of a vertically-stratified shearing box in which the ratio of radiation to gas pressure is ~ 10, and yet no thermal runaway occurs over a timespan ~ 40 cooling times. Where the time-averaged dissipation rate is greater than the critical dissipation rate that creates hydrostatic equilibrium by diffusive radiation flux, the time-averaged radiation flux is held to the critical value, with the excess dissipated energy transported by radiative advection. Although the stress and total pressure are well-correlated as predicted by the alpha-model, we show that stress fluctuations precede pressure fluctuations, contrary to the usual supposition that the pressure controls the saturation level of the magnetic energy. This fact explains the thermal stability. Using a simple toy-model, we show that independently-generated magnetic fluctuations can drive radiation pressure fluctuations, creating a correlation between the two while maintaining thermal stability.

Shigenobu Hirose; Julian H. Krolik; Omer Blaes

2008-09-10T23:59:59.000Z

362

RADIATIVE HEATING OF THE SOLAR CORONA  

SciTech Connect (OSTI)

We investigate the effect of solar visible and infrared radiation on electrons in the Sun's atmosphere using a Monte Carlo simulation of the wave-particle interaction and conclude that sunlight provides at least 40% and possibly all of the power required to heat the corona, with the exception of dense magnetic flux loops. The simulation uses a radiation waveform comprising 100 frequency components spanning the solar blackbody spectrum. Coronal electrons are heated in a stochastic manner by low coherence solar electromagnetic radiation. The wave 'coherence time' and 'coherence volume' for each component is determined from optical theory. The low coherence of solar radiation allows moving electrons to gain energy from the chaotic wave field which imparts multiple random velocity 'kicks' to these particles causing their velocity distribution to broaden or heat. Monte Carlo simulations of broadband solar radiative heating on ensembles of 1000 electrons show heating at per particle levels of 4.0 x 10{sup -21} to 4.0 x 10{sup -20} W, as compared with non-loop radiative loss rates of {approx}1 x 10{sup -20} W per electron. Since radiative losses comprise nearly all of the power losses in the corona, sunlight alone can explain the elevated temperatures in this region. The volume electron heating rate is proportional to density, and protons are assumed to be heated either by plasma waves or through collisions with electrons.

Moran, Thomas G., E-mail: moran@grace.nascom.nasa.gov [Physics Department, Catholic University of America, 200 Hannan Hall, Washington, DC 20064 (United States) and NASA/GSFC, Code 671, Greenbelt, MD 20771 (United States)

2011-10-20T23:59:59.000Z

363

Non Thermal Features in the Cosmic Neutrino Background  

E-Print Network [OSTI]

I review some of the basic information on the Cosmic Neutrino Background momentum distribution. In particular, I discuss how present data from several cosmological observables such as Big Bang Nucleosynthesis, Cosmic Microwave Background and Large Scale Structure power spectrum constrain possible deviations from a standard Fermi-Dirac thermal distribution.

G. Mangano

2006-03-22T23:59:59.000Z

364

Background Long history of research and education in "nuclear  

E-Print Network [OSTI]

· Degradation Nuclear Materials · Multi physics modelling · Severe nuclear accidents · Non destructive testing#12;Background · Long history of research and education in "nuclear engineering" at Chalmers. · "Nuclear engineering" = multi-disciplinary research area. #12;Background Establishment of the Sustainable

Lemurell, Stefan

365

Revised January 2013 Peabody CollegeBackgroundClearance Office  

E-Print Network [OSTI]

personnel will receive a photo ID badge certifying that they have passed a TBI/FBI background check by the BCO office when your file contains the completed/signed consent AND the cleared TBI/FBI report. Non There are no exemptions. Process Once an individual has been granted clearance based off their TBI/FBI background check

Palmeri, Thomas

366

cognitive backgroundCIS4140-2 1 administrivia  

E-Print Network [OSTI]

Cognitive background human-computer interaction understand computer workings (reasonably well) how about humans? once part of psychology now considered cognitive science may also need some sociology later #12;cognitive backgroundCIS4140-2 4 perceptual 2 perceptions considered for UI auditory visual new interfaces

Damon, Craig A.

367

Non-linear evolution of the cosmic neutrino background  

SciTech Connect (OSTI)

We investigate the non-linear evolution of the relic cosmic neutrino background by running large box-size, high resolution N-body simulations which incorporate cold dark matter (CDM) and neutrinos as independent particle species. Our set of simulations explore the properties of neutrinos in a reference ?CDM model with total neutrino masses between 0.05-0.60 eV in cold dark matter haloes of mass 10{sup 11}?10{sup 15} h{sup ?1}M{sub s}un, over a redshift range z = 0?2. We compute the halo mass function and show that it is reasonably well fitted by the Sheth-Tormen formula, once the neutrino contribution to the total matter is removed. More importantly, we focus on the CDM and neutrino properties of the density and peculiar velocity fields in the cosmological volume, inside and in the outskirts of virialized haloes. The dynamical state of the neutrino particles depends strongly on their momentum: whereas neutrinos in the low velocity tail behave similarly to CDM particles, neutrinos in the high velocity tail are not affected by the clustering of the underlying CDM component. We find that the neutrino (linear) unperturbed momentum distribution is modified and mass and redshift dependent deviations from the expected Fermi-Dirac distribution are in place both in the cosmological volume and inside haloes. The neutrino density profiles around virialized haloes have been carefully investigated and a simple fitting formula is provided. The neutrino profile, unlike the cold dark matter one, is found to be cored with core size and central density that depend on the neutrino mass, redshift and mass of the halo, for halos of masses larger than ? 10{sup 13.5}h{sup ?1}M{sub s}un. For lower masses the neutrino profile is best fitted by a simple power-law relation in the range probed by the simulations. The results we obtain are numerically converged in terms of neutrino profiles at the 10% level for scales above ? 200 h{sup ?1}kpc at z = 0, and are stable with respect to box-size and starting redshift of the simulation. Our findings are particularly important in view of upcoming large-scale structure surveys, like Euclid, that are expected to probe the non-linear regime at the percent level with lensing and clustering observations.

Villaescusa-Navarro, Francisco; Viel, Matteo [INAF/Osservatorio Astronomico di Trieste, Via Tiepolo 11, 34143, Trieste (Italy); Bird, Simeon [Institute for Advanced Study, 1 Einstein Drive, Princeton, NJ, 08540 (United States); Peña-Garay, Carlos, E-mail: villaescusa@oats.inaf.it, E-mail: spb@ias.edu, E-mail: penya@ific.uv.es, E-mail: viel@oats.inaf.it [Instituto de Física Corpuscular, CSIC-UVEG, E-46071, Paterna, Valencia (Spain)

2013-03-01T23:59:59.000Z

368

RHOBOT: Radiation hardened robotics  

SciTech Connect (OSTI)

A survey of robotic applications in radioactive environments has been conducted, and analysis of robotic system components and their response to the varying types and strengths of radiation has been completed. Two specific robotic systems for accident recovery and nuclear fuel movement have been analyzed in detail for radiation hardness. Finally, a general design approach for radiation-hardened robotics systems has been developed and is presented. This report completes this project which was funded under the Laboratory Directed Research and Development program.

Bennett, P.C.; Posey, L.D. [Sandia National Labs., Albuquerque, NM (United States)

1997-10-01T23:59:59.000Z

369

Solar radiation intensity calculations  

E-Print Network [OSTI]

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...

Levine, Randolph Steven

1978-01-01T23:59:59.000Z

370

Ship Effect Neutron Measurements And Impacts On Low-Background Experiments  

SciTech Connect (OSTI)

The primary particles entering the upper atmosphere as cosmic rays create showers in the atmosphere that include a broad spectrum of secondary neutrons, muons and protons. These cosmic-ray secondaries interact with materials at the surface of the Earth, yielding prompt backgrounds in radiation detection systems, as well as inducing long-lived activities through spallation events, dominated by the higher-energy neutron secondaries. For historical reasons, the multiple neutrons produced in spallation cascade events are referred to as “ship effect” neutrons. Quantifying the background from cosmic ray induced activities is important to low-background experiments, such as neutrino-less double beta decay. Since direct measurements of the effects of shielding on the cosmic-ray neutron spectrum are not available, Monte Carlo modeling is used to compute such effects. However, there are large uncertainties (orders of magnitude) in the possible cross-section libraries and the cosmic-ray neutron spectrum for the energy range needed in such calculations. The measurements reported here were initiated to validate results from Monte Carlo models through experimental measurements in order to provide some confidence in the model results. The results indicate that the models provide the correct trends of neutron production with increasing density, but there is substantial disagreement between the model and experimental results for the lower-density materials of Al, Fe and Cu.

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Siciliano, Edward R.

2013-10-01T23:59:59.000Z

371

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.

372

Rotating bubble membrane radiator  

DOE Patents [OSTI]

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.

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

1988-12-06T23:59:59.000Z

373

Appendix F. Radiation Appendix F. Radiation F-3  

E-Print Network [OSTI]

from natural and human-made sources. People are exposed to naturally occurring radiation constantlyAppendix F. Radiation #12;#12;Appendix F. Radiation F-3 Appendix F. Radiation This appendix presents basic facts about radiation. The information is intended to be a basis for understanding

Pennycook, Steve

374

Appendix F: Radiation Appendix F: Radiation F-3  

E-Print Network [OSTI]

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix F: Radiation #12;#12;Appendix F: Radiation F-3 P P P E E E N NN HYDROGEN ATOM DEUTERIUM

Pennycook, Steve

375

Appendix F: Radiation Appendix F: Radiation F-3  

E-Print Network [OSTI]

to naturally occurring radiation constantly. For example, cosmic radiation; radon in air; potassium in food on the environment and biological systems. Radiation comes from natural and human-made sources. People are exposedAppendix F: Radiation #12;#12;Appendix F: Radiation F-3 Fig. F.1. The hydrogen atom and its

Pennycook, Steve

376

Appendix G. Radiation Appendix G. Radiation G-3  

E-Print Network [OSTI]

from natural and human-made sources. People are exposed to naturally occurring radiation constantlyAppendix G. Radiation #12;#12;Appendix G. Radiation G-3 Appendix G. Radiation This appendix presents basic facts about radiation. The information is intended to be a basis for un- derstanding

Pennycook, Steve

377

Appendix F. Radiation Appendix F. Radiation F-3  

E-Print Network [OSTI]

from natural and human-made sources. People are exposed to naturally occurring radiation constantlyAppendix F. Radiation #12;#12;Appendix F. Radiation F-3 Appendix F. Radiation This appendix presents basic facts about radiation. The information is intended to be a basis for un- derstanding

Pennycook, Steve

378

assess radiation damage: Topics by E-print Network  

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

than 1.3% and 0.001 at 90% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed. S. K. Sahu et al 1996-04-11 8...

379

acute radiation damage: Topics by E-print Network  

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

than 1.3% and 0.001 at 90% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed. S. K. Sahu et al 1996-04-11 5...

380

attenuation radiation damage: Topics by E-print Network  

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

than 1.3% and 0.001 at 90% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed. S. K. Sahu et al 1996-04-11 6...

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Radiation effects on the blood-brain barrier  

E-Print Network [OSTI]

Selective vascular irradiation enables the critical examination of the vasculature and its role in the onset of late radiation effects. It is a novel approach to expose the endothelial cells to much higher levels of ionizing ...

Raabe, Rebecca L

2007-01-01T23:59:59.000Z

382

Radiation physics, biophysics, and radiation biology  

SciTech Connect (OSTI)

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.

Hall, E.J.

1992-05-01T23:59:59.000Z

383

Final report on the Background Soil Characterization Project at the Oak Ridge Reservation, Oak Ridge, Tennessee. Volume 3: Project Plan  

SciTech Connect (OSTI)

The Background Soil Characterization Project (BSCP) will provide background concentration levels of selected metals, organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents. ORR background soil characterization data will be used for two purposes. The first application will be in differentiating between naturally occurring constituents and site-related contamination. This is a very important step in a risk assessment because if sufficient background data are not available, no constituent known to be a contaminant can be eliminated from the assessment even if the sampled concentration is measured at a minimum level. The second use of the background data will be in calculating baseline risks against which site-specific contamination risks can be compared.

Hatmaker, T.L.; Hook, L.A.; Jackson, B.L. [and others

1993-10-01T23:59:59.000Z

384

Cellular telephone-based radiation sensor and wide-area detection network  

DOE Patents [OSTI]

A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

Craig, William W. (Pittsburg, CA); Labov, Simon E. (Berkeley, CA)

2006-12-12T23:59:59.000Z

385

E-Print Network 3.0 - ambient uv-b radiation Sample Search Results  

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

typically been conducted under low levels of ultraviolet-B (UV-B) radiation, a naturally occurring mutagen... . We conducted experi- ments to test whether the inclusion of...

386

STUDIES OF LASER-DRIVEN RADIATIVE BLAST WAVES A.D. EDENS1  

E-Print Network [OSTI]

-driven radiating blast waves. In the first set of experiments the effect of a drive laser's passage throughSTUDIES OF LASER-DRIVEN RADIATIVE BLAST WAVES A.D. EDENS1 , T. DITMIRE1 , J.F. HANSEN2 , M a background gas on the hydrodynamical evolution of blast waves was examined. The laser's passage heated

Ditmire, Todd

387

Low Level Gamma Spectroscopy Measurements of Radium and Cesium in Lucerne (Medicago Sativa)  

SciTech Connect (OSTI)

Nineteen years after Chernobyl nuclear accident, activity concentration of 137Cs still could be detected in food and soil samples in Central and Eastern Europe. In this paper radiation levels of radium and cesium in Lucerne will be presented. It is a perennial plant with a deep root system and it is widely grown throughout the world as forage for cattle. The samples of Lucerne were taken from twelve different locations in Vojvodina in the summer period July-September 2004. The samples were specially dried on the air and after that ground, powdered and mineralized by method of dry burning on the temperature of 450 deg. C. Gamma spectrometry measurements of the ash were performed by means of actively shielded germanium detector with maximal background reduction. For cesium 137Cs 10 mBq/kg order of magnitude detection limits were achieved.

Fokapic, S.; Bikit, I.; Mrda, D.; Veskovic, M.; Slivka, J. [Department of Physics, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovica 4, 21 000 Novi Sad (Serbia); Mihaljev, Z. [Scientific Veterinary Institute, Rumenacki put 20, 21 000 Novi Sad (Serbia); Cupic, Z. [Research Institute for Reproduction, A.I. and Embryo Transfer Temerin, 21235 Temerin, Industrijska zona bb. (Serbia)

2007-04-23T23:59:59.000Z

388

Spinning Test Particle in Kalb-Ramond background  

E-Print Network [OSTI]

In this work we explore the geodesic deviations of spinning test particles in a string inspired Einstein-Kalb Ramond background. Such a background is known to be equivalent to a spacetime geometry with torsion. We have shown here that the antisymmetric Kalb-Ramond field has significant effect on the geodesic deviation of a spinning test particle. A search for an observational evidence of such an effect in astrophysical experiments may lead to a better undestanding of the geometry of the background spacetime.

Debaprasad Maity; Soumitra SenGupta; Sourav Sur

2005-05-19T23:59:59.000Z

389

Muon-induced backgrounds in the CUORICINO experiment  

SciTech Connect (OSTI)

To better understand the contribution of cosmic ray muons to the CUORICINO background, ten plastic scintillator detectors were installed at the CUORICINO site and operated during 3 months of the CUORICINO experiment. From these measurements, an upper limit of 0.0021 counts/keV {center_dot} kg {center_dot} yr (95% C.L.) was obtained on the cosmic ray induced background in the neutrinoless double beta decay region of interest. The measurements were compared to Geant4 simulations, which are similar to those that will be used to estimate the backgrounds in CUORE.

Andreotti, E; Arnaboldi, C; Avignone, F T; Balata, M; Bandac, I; Barucci, M; Beeman, J W; Bellini, F; Bloxham, T; Brofferio, C; Bryant, A; Bucci, C; Canonica, L; Capelli, S; Carbone, L; Carrettoni, M; Clemenza, M; Cremonesi, O; Creswick, R J; Domizio, S D; Dolinski, M J; Ejzak, L; Faccini, R; Farach, H A; Ferri, E; Ferroni, F; Firoini, E; Foggetta, L; Giachero, A; Gironi, L; Giuliani, A; Gorla, P; Guardincerri, E; Gutierrez, T D; Haller, E E; Kadel, R; Kazkaz, K; Kraft, S; Kogler, L; Kolomensky, Y G; Maiano, C; Maruyama, R H; Martinez, C; Martinez, M; Mizouni, L; Morganti, S; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; Orio, F; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pirro, S; Previtali, E; Risegari, L; Rosenfeld, C; Rusconi, C; Salvioni, C; Sangiorgio, S; Schaeffer, D; Scielzo, N D; Sisti, M; Smith, A R; Tomei, C; Ventura, G; Vignati, M

2009-11-16T23:59:59.000Z

390

Flavor singlet physics in lattice QCD with background fields  

SciTech Connect (OSTI)

We show that hadronic matrix elements can be extracted from lattice simulations with background fields that arise from operator exponentiation. Importantly, flavor-singlet matrix elements can be evaluated without requiring the computation of disconnected diagrams, thus facilitating a calculation of the quark contribution to the spin of the proton and the singlet axial coupling, g{sub A}{sup 0}. In the two-nucleon sector, a background field approach will allow calculation of the magnetic and quadrupole moments of the deuteron and an investigation of the EMC effect directly from lattice QCD. Matrix elements between states of differing momenta are also analyzed in the presence of background fields.

Detmold, W. [Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195 (United States)

2005-03-01T23:59:59.000Z

391

Radiation Leukemogenesis at Low Dose Rates  

SciTech Connect (OSTI)

The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an 'inverse dose rate effect' for some tumor types. That is, for the development of some tumor types low dose rate exposures carry greater risks than acute exposures.

Weil, Michael; Ullrich, Robert

2013-09-25T23:59:59.000Z

392

Systematics of Coupling Flows in AdS Backgrounds  

E-Print Network [OSTI]

the value of the low energy tree-level coupling g 4 . Givenlogarithmic running with energy even at tree-level. In a GUT

Goldberger, Walter D.

2009-01-01T23:59:59.000Z

393

SCIENTIFIC CORRESPONDENCE Radiation doses  

E-Print Network [OSTI]

SCIENTIFIC CORRESPONDENCE Radiation doses and cancert-A T. w- - SIR- In February 1990, the Soviet. Nikipelov et al. published in g Priroda (Nature)' the radiation doses for each year, averaged over environmental impact on the Gulf waters is rapidly ex- ported to the Arabian Sea and then to the Indian Ocean

Shlyakhter, Ilya

394

Radiative Flux Analysis  

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

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.

Long, Chuck [NOAA

395

First calculation of cosmic-ray muon spallation backgrounds for MeV astrophysical neutrino signals in Super-Kamiokande  

E-Print Network [OSTI]

When muons travel through matter, their energy losses lead to nuclear breakup ("spallation") processes. The delayed decays of unstable daughter nuclei produced by cosmic-ray muons are important backgrounds for low-energy astrophysical neutrino experiments, e.g., those seeking to detect solar neutrino or Diffuse Supernova Neutrino Background (DSNB) signals. Even though Super-Kamiokande has strong general cuts to reduce these spallation-induced backgrounds, the remaining rate before additional cuts for specific signals is much larger than the signal rates for kinetic energies of about 6 -- 18 MeV. Surprisingly, there is no published calculation of the production and properties of these backgrounds in water, though there are such studies for scintillator. Using the simulation code FLUKA and theoretical insights, we detail how muons lose energy in water, produce secondary particles, how and where these secondaries produce isotopes, and the properties of the backgrounds from their decays. We reproduce Super-Kamiokande measurements of the total background to within a factor of 2, which is good given that the isotope yields vary by orders of magnitude and that some details of the experiment are unknown to us at this level. Our results break aggregate data into component isotopes, reveal their separate production mechanisms, and preserve correlations between them. We outline how to implement more effective background rejection techniques using this information. Reducing backgrounds in solar and DSNB studies by even a factor of a few could help lead to important new discoveries.

Shirley Weishi Li; John F. Beacom

2014-04-13T23:59:59.000Z

396

Nuclear radiation actuated valve  

DOE Patents [OSTI]

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.

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

1985-01-01T23:59:59.000Z

397

Reduction of background clutter in structured lighting systems  

DOE Patents [OSTI]

Methods for segmenting the reflected light of an illumination source having a characteristic wavelength from background illumination (i.e. clutter) in structured lighting systems can comprise pulsing the light source used to illuminate a scene, pulsing the light source synchronously with the opening of a shutter in an imaging device, estimating the contribution of background clutter by interpolation of images of the scene collected at multiple spectral bands not including the characteristic wavelength and subtracting the estimated background contribution from an image of the scene comprising the wavelength of the light source and, placing a polarizing filter between the imaging device and the scene, where the illumination source can be polarized in the same orientation as the polarizing filter. Apparatus for segmenting the light of an illumination source from background illumination can comprise an illuminator, an image receiver for receiving images of multiple spectral bands, a processor for calculations and interpolations, and a polarizing filter.

Carlson, Jeffrey J.; Giles, Michael K.; Padilla, Denise D.; Davidson Jr., Patrick A.; Novick, David K.; Wilson, Christopher W.

2010-06-22T23:59:59.000Z

398

Inductive Rules, Background Knowledge, and Skepticism Daniel Steel  

E-Print Network [OSTI]

Inductive Rules, Background Knowledge, and Skepticism Daniel Steel Department of Philosophy 503 S. Kedzie Hall Michigan State University East Lansing, MI 48823-1032 Email: steel@msu.edu #12;Abstract

Steel, Daniel

399

1 Mathematical Background 1 1.1 Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . 1  

E-Print Network [OSTI]

Contents 1 Mathematical Background 1 1.1 Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Computability Theory . . . . . . . . . . . . . . . . . . . . 4 1.3 Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.4 Probability Theory . . . . . . . . . . . . . . . . . . . . . . 8 1.5 Exercises and Problems

Goodman, James R.

400

1 Introduction 1 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1  

E-Print Network [OSTI]

Contents 1 Introduction 1 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Our Goal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.3 ICSI's HMM/ANN Hybrid Speech Recognition System . . . . . . . . 2 1.4 What is Multi­band Processing

Mirghafori, N. Nikki

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Higgs boson production at hadron colliders: Signal and background processes  

SciTech Connect (OSTI)

We review the theoretical status of signal and background calculations for Higgs boson production at hadron colliders. Particular emphasis is given to missing NLO results, which will play a crucial role for the Tevatron and the LHC.

David Rainwater; Michael Spira; Dieter Zeppenfeld

2004-01-12T23:59:59.000Z

402

Lovelock black holes in a string cloud background  

E-Print Network [OSTI]

We present an exact static, spherically symmetric black hole solution to the third order Lovelock gravity with a string cloud background in seven dimensions for the special case when the second and third order Lovelock coefficients are related via $\\tilde{\\alpha}^2_2=3\\tilde{\\alpha}_3\\;(\\equiv\\alpha^2)$. Further, we examine thermodynamic properties of this black hole to obtain exact expressions for mass, temperature, entropy and also perform the thermodynamic stability analysis. We see that a string cloud background makes a profound influence on horizon structure, thermodynamic properties and the stability of black holes. Interestingly, the entropy of the black hole is unaffected due to a string cloud background. However, the critical solution for thermodynamic stability is being affected by a string cloud background.

Tae-Hun Lee; Dharmanand Baboolal; Sushant G. Ghosh

2014-09-12T23:59:59.000Z

403

The Cosmic Near Infrared Background: Remnant Light from Early Stars  

E-Print Network [OSTI]

The redshifted ultraviolet light from early stars at z ~ 10 contributes to the cosmic near infrared background. We present detailed calculations of its spectrum with various assumptions about metallicity and mass spectrum of early stars. We show that if the near infrared background has a stellar origin, metal-free stars are not the only explanation of the excess near infrared background; stars with metals (e.g. Z=1/50 Z_sun) can produce the same amount of background intensity as the metal-free stars. We quantitatively show that the predicted average intensity at 1-2 microns is essentially determined by the efficiency of nuclear burning in stars, which is not very sensitive to metallicity. We predict \

Elizabeth Fernandez; Eiichiro Komatsu

2005-08-08T23:59:59.000Z

404

Holographic superconductor developed in BTZ black hole background with backreactions  

E-Print Network [OSTI]

We develop a holographic superconductor in BTZ black hole background with backreactions. We investigate the influence of the backreaction on the condensation of the scalar hair and the dynamics of perturbation in the background spacetime. When the Breitenlohner-Freedman bound is approached, we argue that only one of two possible operators can reflect the real property of the condensation in the holographic superconductor. This argument is supported by the investigation in dynamics.

Yunqi Liu; Qiyuan Pan; Bin Wang

2011-06-22T23:59:59.000Z

405

The X-ray background and the evolution of AGN  

E-Print Network [OSTI]

We discuss the constraints on the AGN evolution from the cosmic X-ray background and source counts. A synthesis model to fit the X-ray background is presented. In the model, the spectrum of type 2 AGN has been modeled including Compton down--scattering within the absorbing material. Besides, we introduced a dependence on redshift of the relative number of obscured sources and found a decrease of the fraction of type 2 AGN at redshifts larger than 2.

Fulvio Pompilio; Fabio La Franca; Giorgio Matt

1999-09-23T23:59:59.000Z

406

Muon-induced backgrounds in the CUORICINO experiment  

SciTech Connect (OSTI)

To better understand the contribution of cosmic ray muons to the CUORICINO background, ten plastic scintillator detectors were installed at the CUORICINO siteand operated during the final 3 months of the experiment. From these measurements, an upper limit of 0.0021 counts/(keV.kg.yr) (95percent c.l.) was obtained on the cosmicray induced background in the neutrinoless double beta decay region of interest. The measurements were also compared to Geant4 simulations.

Andreotti, E.; Arnaboldi, C.; Avignone III, F. T.; Balata, M.; Bandac, I.; Barucci, M.; Beeman, J. W.; Bellini, F.; Bloxham, T.; Brofferio, C.; Bryant, A.; Bucci, C.; Canonica, L.; Capelli, S.; Carbone, L.; Carrettoni, M.; Clemenza, M.; Cremonesi, O.; Creswick, R. J.; Domizio, S. Di; Dolinski, M. J.; Ejzak, L.; Faccini, R.; Farach, H. A.; Ferri, E.; Ferroni, F.; Fiorini, E.; Foggetta, L.; Giachero, A.; Gironi, L.; Giuliani, A.; Gorla, P.; Guardincerri, E.; Gutierrez, T. D.; Haller, E. E.; Kadel, R.; Kazkaz, K.; Kraft, S.; Kogler, L.; Kolomensky, Yu. G.; Maiano, C.; Maruyama, R. H.; Martinez, C.; Martinez, M.; Mizouni, L.; Morganti, S.; Nisi, S.; Nones, C.; Norman, E. B.; Nucciotti, A.; Orio, F.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pedretti, M.; Pessina, G.; Pirro, S.; Previtali, E.; Risegari, L.; Rosenfeld, C.; Rusconi, C.; Salvioni, C.; Sangiorgio, S.; Schaeffer, D.; Scielzo, N. D.; Sisti, M.; Smith, A. R.; Tomei, C.; Ventura, G.; Vignati, M.

2010-04-15T23:59:59.000Z

407

Radiative and climate impacts of absorbing aerosols  

E-Print Network [OSTI]

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

Zhu, Aihua

2010-01-01T23:59:59.000Z

408

Background studies for NaI(Tl) detectors in the ANAIS dark matter project  

SciTech Connect (OSTI)

Several large NaI(Tl) detectors, produced by different companies, have been operated in the Canfranc Underground Laboratory (LSC) in the frame of the ANAIS (Annual modulation with NaI Scintillators) project devoted to the direct detection of dark matter. A complete background model has been developed for a 9.6 kg detector (referred as ANAIS-0 prototype) after a long data taking at LSC. Activities from the natural chains of {sup 238}U and {sup 232}Th, and {sup 40}K in the NaI(Tl) crystal were evaluated applying different methods: discrimination of alpha particles vs beta/gamma background by Pulse Shape Analysis for quantifying the content of the natural chains and coincidence techniques for {sup 40}K. Radioactive contaminations in the detector and shielding components were also determined by HPGe spectrometry. Monte Carlo simulations using Geant4 package were carried out to evaluate their contribution. At high energies, most of the measured background is nicely reproduced; at low energy some non-explained components are still present, although some plausible background sources have been analyzed. The {sup 40}K content of the NaI(Tl) crystal has been confirmed to be the dominant contributor to the measured background with this detector. In addition, preliminary results of the background characterization, presently underway at the LSC, of two recently produced NaI(Tl) detectors, with 12.5 kg mass each, will be presented: cosmogenic induced activity has been clearly observed and is being quantified, and {sup 40}K activity at a level ten times lower than in ANAIS-0 has been determined.

Amaré, J.; Borjabad, S.; Cebrián, S.; Cuesta, C.; Fortuño, D.; García, E.; Ginestra, C.; Gómez, H.; Martínez, M.; Oliván, M. A.; Ortigoza, Y.; Solórzano, A. Ortiz de; Pobes, C.; Puimedón, J.; Sarsa, M. L.; Villar, J. A.; Villar, P. [Laboratorio de Física Nuclear y Astropartículas, Universidad de Zaragoza, Calle Pedro Cerbuna 12, 50009 Zaragoza, Spain and Laboratorio Subterráneo de Canfranc, Paseo de los Ayerbe s/n, 22880 Canfranc Estación, Huesca (Spain)] [Laboratorio de Física Nuclear y Astropartículas, Universidad de Zaragoza, Calle Pedro Cerbuna 12, 50009 Zaragoza, Spain and Laboratorio Subterráneo de Canfranc, Paseo de los Ayerbe s/n, 22880 Canfranc Estación, Huesca (Spain)

2013-08-08T23:59:59.000Z

409

Air fluidized balls in a background of smaller beads  

E-Print Network [OSTI]

We report on quasi-two-dimensional granular systems in which either one or two large balls is fluidized by an upflow of air in the presence of a background of several hundred smaller beads. A single large ball is observed to propel ballistically in nearly circular orbits, in direct contrast to the Brownian behavior of a large ball fluidized in the absence of this background. Further, the large ball motion satisfies a Langevin equation with an additional speed-dependent force acting in the direction of motion. This results in a non-zero average speed of the large ball that is an order of magnitude faster than the root mean square speed of the background balls. Two large balls fluidized in the absence of the small-bead background experience a repulsive force depending only on the separation of the two balls. With the background beads present, by contrast, the ball-ball interaction becomes velocity-dependent and attractive. The attraction is long-ranged and inconsistent with a depletion model; instead, it is mediated by local fluctuations in the density of the background beads which depends on the large balls' motion.

M. E. Beverland; L. J. Daniels; D. J. Durian

2010-12-02T23:59:59.000Z

410

GROUND LEVEL INVESTIGATION OF ANOMALOUS RADIATION LEVELS IN NIAGARA FALLS, NEW YORK  

Office of Legacy Management (LM)

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofof EnergyYou$ EGcG ENERGYELIkNATION REPORTFairfield,? . -

411

Coherent Radiation in an Undulator  

E-Print Network [OSTI]

solving the particle-radiation system in a self-consistentto clarify the coherent radiation mechanism. References 1.the Proceedings Coherent Radiation in an Undulator Y,H. Chin

Chin, Y.H.

2011-01-01T23:59:59.000Z

412

The Properties of Undulator Radiation  

E-Print Network [OSTI]

of a Dedicated Synchrotron Radiation Facility," IEEE Trans.1983), "Characteristics of Synchrotron Radiation and of itsHandbook on Synchrotron Radiation, E. -E. Koch.1A. 65-172,

Howells, M.R.

2011-01-01T23:59:59.000Z

413

Radiation Safety (Revised March 2010)  

E-Print Network [OSTI]

Radiation Safety Manual (Revised March 2010) Updated December 2012 Stanford University, Stanford California #12; #12; Radiation Safety Manual (Revised March 2010) Updated Environmental Health and Safety, Stanford University, Stanford California #12; CREDITS This Radiation Safety

Kay, Mark A.

414

Cloud of strings for radiating black holes in Lovelock gravity  

E-Print Network [OSTI]

We present exact spherically symmetric null dust solutions in the third order Lovelock gravity with a string cloud background in arbitrary $N$ dimensions,. This represents radiating black holes and generalizes the well known Vaidya solution to Lovelock gravity with a string cloud in the background. We also discuss the energy conditions and horizon structures, and explicitly bring out the effect of the string clouds on the horizon structure of black hole solutions for the higher dimensional general relativity and Einstein-Gauss-Bonnet theories. It turns out that the presence of the coupling constant of the Gauss-Bonnet terms and/or background string clouds completely changes the structure of the horizon and this may lead to a naked singularity. We recover known spherically symmetric radiating models as well as static black holes in the appropriate limits.

Sushant G. Ghosh; Sunil D. Maharaj

2014-09-28T23:59:59.000Z

415

LSU School of Dentistry Laser Safety : Clinical SAFETY PROCEDURES FOR LASER (NON-IONIZING) RADIATION  

E-Print Network [OSTI]

system is one that is considered to be incapable of producing damaging radiation levels during operation-IONIZING) RADIATION 1. PURPOSE This procedure sets forth the Louisiana State University (LSU) System non-ionizing radiation safety policy and procedural requirements of the program. The use of the term non

416

Nuclear radiation-warning detector that measures impedance  

DOE Patents [OSTI]

This invention is a nuclear radiation-warning detector that measures impedance of silver-silver halide on an interdigitated electrode to detect light or radiation comprised of alpha particles, beta particles, gamma rays, X rays, and/or neutrons. The detector is comprised of an interdigitated electrode covered by a layer of silver halide. After exposure to alpha particles, beta particles, X rays, gamma rays, neutron radiation, or light, the silver halide is reduced to silver in the presence of a reducing solution. The change from the high electrical resistance (impedance) of silver halide to the low resistance of silver provides the radiation warning that detected radiation levels exceed a predetermined radiation dose threshold.

Savignac, Noel Felix; Gomez, Leo S; Yelton, William Graham; Robinson, Alex; Limmer, Steven

2013-06-04T23:59:59.000Z

417

Statistical aspects of determining compliance with radiation standards  

SciTech Connect (OSTI)

Radiation surveys are an important tool used to monitor the safety of operations at nuclear fuel cycle facilities, as well as determining if contaminated sites require remedial action before license termination or unrestricted release. It is important that radiation surveys are carefully designed to provide the right quantity and quality of useful information for making valid decisions concerning public safety. The validity of survey information is especially important when low-level radiation detection techniques are required such as for environmental radiation monitoring. Thus, statistical aspects of radiation surveys are important in demonstrating compliance with radiation guidelines and for deciding when remedial action or cleanup is required. In this paper, we discuss the statistical aspects of evaluating whether guidelines are, in fact, being exceeded.

Kennedy, W.E. Jr.; Kinnison, R.R.; Gilbert, R.O.; Watson, E.C.

1980-01-01T23:59:59.000Z

418

DOE occupational radiation exposure. Report 1992--1994  

SciTech Connect (OSTI)

The DOE Occupational Radiation Exposure Report, 1992-1994 reports occupational radiation exposures incurred by individuals at US Department of Energy (DOE) facilities from 1992 through 1994. This report includes occupational radiation exposure information for all DOE employees, contractors, subcontractors, and visitors. This information is analyzed and trended over time to provide a measure of the DOE`s performance in protecting its workers from radiation. Occupational radiation exposure at DOE has been decreasing over the past 5 years. In particular, doses in the higher dose ranges are decreasing, including the number of doses in excess of the DOE limits and doses in excess of the 2 rem Administrative Control Level (ACL). This is an indication of greater attention being given to protecting these individuals from radiation in the workplace.

NONE

1997-05-01T23:59:59.000Z

419

Energy enhancement of proton acceleration in combinational radiation pressure and bubble by optimizing plasma density  

SciTech Connect (OSTI)

The combinational laser radiation pressure and plasma bubble fields to accelerate protons are researched through theoretical analysis and numerical simulations. The dephasing length of the accelerated protons bunch in the front of the bubble and the density gradient effect of background plasma on the accelerating phase are analyzed in detail theoretically. The radiation damping effect on the accelerated protons energy is also considered. And it is demonstrated by two-dimensional particle-in-cell simulations that the protons bunch energy can be increased by using the background plasma with negative density gradient. However, radiation damping makes the maximal energy of the accelerated protons a little reduction.

Bake, Muhammad Ali; Xie Baisong [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Shan Zhang [Department of Mathematics and Physics, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Hong Xueren [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Wang Hongyu [Department of Physics, Anshan Normal University, Anshan 114005 (China); Shanghai Bright-Tech Information Technology Co. Ltd, Shanghai 200136 (China)

2012-08-15T23:59:59.000Z

420

Evaluation of ultra-low background materials for uranium and thorium using ICP-MS  

SciTech Connect (OSTI)

An increasing number of physics experiments require low background materials for their construction. The presence of Uranium and Thorium and their progeny in these materials present a variety of unwanted background sources for these experiments. The sensitivity of the experiments continues to drive the necessary levels of detection ever lower as well. This requirement for greater sensitivity has rendered direct radioassay impractical in many cases requiring large quantities of material, frequently many kilograms, and prolonged counting times, often months. Other assay techniques have been employed such as Neutron Activation Analysis but this requires access to expensive facilities and instrumentation and can be further complicated and delayed by the formation of unwanted radionuclides. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is a useful tool and recent advancements have increased the sensitivity particularly in the elemental high mass range of U and Th. Unlike direct radioassay, ICP-MS is a destructive technique since it requires the sample to be in liquid form which is aspirated into a high temperature plasma. But it benefits in that it usually requires a very small sample, typically about a gram. This paper discusses how a variety of low background materials such as copper, polymers, and fused silica are made amenable to ICP-MS assay and how the arduous task of maintaining low backgrounds of U and Th is achieved.

Hoppe, E. W.; Overman, N. R.; LaFerriere, B. D. [Pacific Northwest National Laboratory, Richland, WA 99354 (United States)] [Pacific Northwest National Laboratory, Richland, WA 99354 (United States)

2013-08-08T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Evaluation of Ultra-Low Background Materials for Uranium and Thorium Using ICP-MS  

SciTech Connect (OSTI)

An increasing number of physics experiments require low background materials for their construction. The presence of Uranium and Thorium and their progeny in these materials present a variety of unwanted background sources for these experiments. The sensitivity of the experiments continues to drive the necessary levels of detection ever lower as well. This requirement for greater sensitivity has rendered direct radioassay impractical in many cases requiring large quantities of material, frequently many kilograms, and prolonged counting times, often months. Other assay techniques have been employed such as Neutron Activation Analysis but this requires access to expensive facilities and instrumentation and can be further complicated and delayed by the formation of unwanted radionuclides. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is a useful tool and recent advancements have increased the sensitivity particularly in the elemental high mass range of U and Th. Unlike direct radioassay, ICP-MS is a destructive technique since it requires the sample to be in liquid form which is aspirated into a high temperature plasma. But it benefits in that it usually requires a very small sample, typically about a gram. Here we will discuss how a variety of low background materials such as copper, polymers, and fused silica are made amenable to ICP-MS assay and how the arduous task of maintaining low backgrounds of U and Th is achieved.

Hoppe, Eric W.; Overman, Nicole R.; LaFerriere, Brian D.

2013-08-08T23:59:59.000Z

422

SYNCHROTRON RADIATION SOURCES  

SciTech Connect (OSTI)

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.

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

1998-07-01T23:59:59.000Z

423

Radiation Protection | The Ames Laboratory  

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

Radiation Protection Radiation Protection Regulations: The Federal Regulation governing the use of radioactive materials at Ames Laboratory is 10 CFR 835. To implement this...

424

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...

425

Neural networks and separation of background and foregrounds in astrophysical sky maps  

E-Print Network [OSTI]

The Independent Component Analysis (ICA) algorithm is implemented as a neuralnetwork for separating signals of different origin in astrophysical sky maps.Due to its self-organizing capability, it works without prior assumptions onthe signals, neither on their frequency scaling, nor on the signal mapsthemselves; instead, it learns directly from the input data how to separate thephysical components, making use of their statistical independence. To test thecapabilities of this approach, we apply the ICA algorithm on sky patches, takenfrom simulations and observations, at the microwave frequencies, that are goingto be deeply explored in a few years on the whole sky, by the MicrowaveAnisotropy Probe (MAP) and by the {\\sc Planck} Surveyor Satellite. The maps areat the frequencies of the Low Frequency Instrument (LFI) aboard the {\\scPlanck} satellite (30, 44, 70 and 100 GHz), and contain simulated astrophysicalradio sources, Cosmic Microwave Background (CMB) radiation, and Galacticdiffuse emissions from thermal dust...

Baccigalupi, C; Burigana, C; De Zotti, G; Farusi, A; Maino, D; Maris, M; Perrotta, F; Salerno, E; Toffolatti, L; Tonazzini, A

2000-01-01T23:59:59.000Z

426

Composition for radiation shielding  

DOE Patents [OSTI]

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.

Kronberg, James W. (Aiken, SC)

1994-01-01T23:59:59.000Z

427

The Intense Radiation Gas  

E-Print Network [OSTI]

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.

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

2005-03-08T23:59:59.000Z

428

Background-independent measurement of $?_{13}$ in Double Chooz  

E-Print Network [OSTI]

The oscillation results published by the Double Chooz collaboration in 2011 and 2012 rely on background models substantiated by reactor-on data. In this analysis, we present a background-model-independent measurement of the mixing angle $\\theta_{13}$ by including 7.53 days of reactor-off data. A global fit of the observed neutrino rates for different reactor power conditions is performed, yielding a measurement of both $\\theta_{13}$ and the total background rate. The results on the mixing angle are improved significantly by including the reactor-off data in the fit, as it provides a direct measurement of the total background rate. This reactor rate modulation analysis considers antineutrino candidates with neutron captures on both Gd and H, whose combination yields $\\sin^2(2\\theta_{13})=$ 0.102 $\\pm$ 0.028(stat.) $\\pm$ 0.033(syst.). The results presented in this study are fully consistent with the ones already published by Double Chooz, achieving a competitive precision. They provide, for the first time, a determination of $\\theta_{13}$ that does not depend on a background model.

Y. Abe; J. C. dos Anjos; J. C. Barriere; E. Baussan; I. Bekman; M. Bergevin; T. J. C. Bezerra; L. Bezrukov; E. Blucher; C. Buck; J. Busenitz; A. Cabrera; E. Caden; L. Camilleri; R. Carr; M. Cerrada; P. -J. Chang; E. Chauveau; P. Chimenti; A. P. Collin; E. Conover; J. M. Conrad; J. I. Crespo-Anadón; K. Crum; A. Cucoanes; E. Damon; J. V. Dawson; D. Dietrich; Z. Djurcic; M. Dracos; M. Elnimr; A. Etenko; M. Fallot; F. von Feilitzsch; J. Felde; S. M. Fernandes; V. Fischer; D. Franco; M. Franke; H. Furuta; I. Gil-Botella; L. Giot; M. Göger-Neff; L. F. G. Gonzalez; L. Goodenough; M. C. Goodman; C. Grant; N. Haag; T. Hara; J. Haser; M. Hofmann; G. A. Horton-Smith; A. Hourlier; M. Ishitsuka; J. Jochum; C. Jollet; F. Kaether; L. N. Kalousis; Y. Kamyshkov; D. M. Kaplan; T. Kawasaki; E. Kemp; H. de Kerret; T. Konno; D. Kryn; M. Kuze; T. Lachenmaier; C. E. Lane; T. Lasserre; A. Letourneau; D. Lhuillier; H. P. Lima Jr; M. Lindner; J. M. López-Castaño; J. M. LoSecco; B. K. Lubsandorzhiev; S. Lucht; J. Maeda; C. Mariani; J. Maricic; J. Martino; T. Matsubara; G. Mention; A. Meregaglia; T. Miletic; R. Milincic; A. Minotti; Y. Nagasaka; K. Nakajima; Y. Nikitenko; P. Novella; M. Obolensky; L. Oberauer; A. Onillon; A. Osborn; C. Palomares; I. M. Pepe; S. Perasso; P. Pfahler; A. Porta; G. Pronost; J. Reichenbacher; B. Reinhold; M. Röhling; R. Roncin; S. Roth; B. Rybolt; Y. Sakamoto; R. Santorelli; F. Sato; A. C. Schilithz; S. Schönert; S. Schoppmann; M. H. Shaevitz; R. Sharankova; S. Shimojima; V. Sibille; V. Sinev; M. Skorokhvatov; E. Smith; J. Spitz; A. Stahl; I. Stancu; L. F. F. Stokes; M. Strait; A. Stüken; F. Suekane; S. Sukhotin; T. Sumiyoshi; Y. Sun; R. Svoboda; K. Terao; A. Tonazzo; H. H. Trinh Thi; G. Valdiviesso; N. Vassilopoulos; C. Veyssiere; M. Vivier; S. Wagner; H. Watanabe; C. Wiebusch; L. Winslow; M. Wurm; G. Yang; F. Yermia; V. Zimmer

2014-04-25T23:59:59.000Z

429

The Big Bang, COBE, and the Relic Radiation of Creation (LBNL Science at the Theater)  

ScienceCinema (OSTI)

Berkeley Lab's George Smoot won the 2006 Physics Nobel Prize, together with John Mather of NASA Goddard Space Flight Center, for "the discovery of the blackbody form and anisotropy of the cosmic microwave background radiation." The anisotropy showed as small variations in the map of the early universe. This research looks back into the infant universe and provides a better understanding of the origin of galaxies and stars. The cosmic background radiation is a tool to understand the structure and history of the universe and the structure of space-time. These observations have provided increased support for the big bang theory of the universe's origin. The Cosmic Background Explorer (COBE) NASA satellite, launched in 1989, carries instruments that measured various aspects of cosmic microwave background radiation, and produced the data for these compelling scientific results, which opened up a field that continues very actively today.

Smoot, George

2011-04-28T23:59:59.000Z

430

RESEARCH SAFETY RADIATION SAFETY  

E-Print Network [OSTI]

RESEARCH SAFETY RADIATION SAFETY ENVIRONMENTAL PROGRAMS HAZARDOUS MATERIALS CONTROLLED SUBSTANCES INTEGRATED WASTE MANAGEMENT LABORATORY SAFETY AUDITS & COMPLIANCE BIOSAFETY and ENVIRONMENTAL HEALTH EMERGENCY MANAGEMENT and MISSION CONTINUITY FIRE PREVENTION and LIFE SAFETY GENERAL SAFETY TRAINING

431

Amorphous silicon radiation detectors  

DOE Patents [OSTI]

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.

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

1992-01-01T23:59:59.000Z

432

Amorphous silicon radiation detectors  

DOE Patents [OSTI]

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.

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

1992-11-17T23:59:59.000Z

433

Adaptive multigroup radiation diffusion  

E-Print Network [OSTI]

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 ...

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

2005-01-01T23:59:59.000Z

434

Method of enhancing radiation response of radiation detection materials  

DOE Patents [OSTI]

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.

Miller, Steven D. (Richland, WA)

1997-01-01T23:59:59.000Z

435

Radiation Safety Manual Dec 2012 Page 1 RADIATION SAFETY  

E-Print Network [OSTI]

Radiation 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 ­ Dec 2012 Page 1 Table of Contents Introduction Chapter I: Radiation Safety Program A. Program

Grishok, Alla

436

Radiation Safety Training Basic Radiation Safety Training for  

E-Print Network [OSTI]

Radiation Safety Training Basic Radiation Safety Training for Sealed Source Users for Physics 461 & 462 Modern Physics Laboratory Spring 2007 #12;Radiation Safety Department, University of Tennessee Purpose: To provide basic radiation safety training to the users of sealed sources located

Dai, Pengcheng

437

Radiation Safety Training Basic Radiation Safety Training for  

E-Print Network [OSTI]

Radiation Safety Training Basic Radiation Safety Training for X-ray Users for Physics 461 & 462 Modern Physics Laboratory Spring 2007 #12;#12;Radiation Safety Department, University of Tennessee Protocol Title: Basic Radiation Safety Training for X-ray Users Drafted By: Chris Millsaps, RSS Reviewers

Dai, Pengcheng

438

The local potential approximation in the background field formalism  

E-Print Network [OSTI]

Working within the familiar local potential approximation, and concentrating on the example of a single scalar field in three dimensions, we show that the commonly used approximation method of identifying the total and background fields, leads to pathologies in the resulting fixed point structure and the associated spaces of eigenoperators. We then show how a consistent treatment of the background field through the corresponding modified shift Ward identity, can cure these pathologies, restoring universality of physical quantities with respect to the choice of dependence on the background field, even within the local potential approximation. Along the way we point out similarities to what has been previously found in the f(R) approximation in asymptotic safety for gravity.

I. Hamzaan Bridle; Juergen A. Dietz; Tim R. Morris

2014-03-20T23:59:59.000Z

439

Reducing 68Ge Background in Dark Matter Experiments  

SciTech Connect (OSTI)

Experimental searches for dark matter include experiments with sub-0.5 keV-energy threshold high purity germanium detectors. Experimental efforts, in partnership with the CoGeNT Collaboration operating at the Soudan Underground Laboratory, are focusing on energy threshold reduction via noise abatement, reduction of backgrounds from cosmic ray generated isotopes, and ubiquitous environmental radioactive sources. The most significant cosmic ray produced radionuclide is 68Ge. This paper evaluates reducing this background by freshly mining and processing germanium ore. The most probable outcome is a reduction of the background by a factor of two, and at most a factor of four. A very cost effective alternative is to obtain processed Ge as soon as possible and store it underground for 18 months.

Kouzes, Richard T.; Orrell, John L.

2011-03-01T23:59:59.000Z

440

Direct Imaging of Exoplanets Without Background Subtraction: Implications for ELTs  

E-Print Network [OSTI]

The ultra-high contrast capability required to form images of other solar systems is arguably the highest-profile challenge in astronomy today. The current high-contrast imaging efforts all require background subtraction to separate the planetary image from the image of the host star. Background estimation is difficult due to the presence of non-common path aberrations (NCPAs) that change with time. The only major source of information that is not being utilized by current efforts is the random encoding of the planetary image and the NCPAs by the atmosphere on millisecond time-scales. Here, a method that utilizes this information in order to avoid background subtraction altogether is proposed. This new paradigm will allow simultaneous estimation of the time-dependent NCPAs and the planetary image via rigorous statistical inference procedures. These procedures are fully compatible with other information sources, such as diurnal field rotation and spectral diversity. Given the open-ended nature of the backgroun...

Frazin, Richard A

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "background radiation levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Origin of background electron concentration in InxGa1-xN alloys  

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

The origin of high background electron concentration (n) in InxGa1-xN alloys has been investigated. A shallow donor was identified as having an energy level (ED1) that decreases with x (ED1 = 16 meV at x = 0 and ED1 = 0 eV at x ~ 0.5) and that crossover the conduction band at x ~ 0.5. This shallow donor is believed to be the most probable cause of high n in InGaN. This understanding is consistent with the fact that n increases sharply with an increase in x and becomes constant for x > 0.5. A continuous reduction in n was obtained by increasing the V/III ratio during the epilayer growth, suggesting that nitrogen vacancy-related impurities are a potential cause of the shallow donors and high background electron concentration in InGaN

Pantha, B. N.; Wang, H.; Khan, N.; Lin, J. Y.; Jiang, H. X.

2011-08-01T23:59:59.000Z

442

GERDA phase II detectors: Behind the production and characterisation at low background conditions  

SciTech Connect (OSTI)

The low background GERmanium Detector Array (GERDA) at Laboratori Nazionali del Gran Sasso (LNGS) is designed to search for the rare neutrinoless double beta decay (0???) in {sup 76}Ge. Bare germanium diodes are operated in liquid argon which is used as coolant, as passive and soon active as well shield against external radiation. Currently, Phase I of the experiment is running using ?15 kg of co-axial High Purity Germanium diodes. In order to increase the sensitivity of the experiment 30 Broad Energy Germanium (BEGe) diodes will be added within 2013. This presentation reviews the production chain of the new BEGe detectors from isotopic enrichment to diode production and testing. As demonstrated all steps were carefully planned in order to minimize the exposure of the enriched germanium to cosmic radiation. Following this premise, acceptance and characterisation measurement of the newly produced diodes have been performed within the HEROICA project in the Belgian underground laboratory HADES close to the diode manufacturer. The test program and the results from a subset of the recently terminated GERDA Phase II BEGe survey will be presented.

Maneschg, Werner [Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)] [Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Collaboration: GERDA Collaboration; and others

2013-08-08T23:59:59.000Z

443

Packet personal radiation monitor  

DOE Patents [OSTI]

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.

Phelps, James E. (Knoxville, TN)

1989-01-01T23:59:59.000Z

444

A Stable Magnetic Background in SU(2) QCD  

E-Print Network [OSTI]

Motivated by the instability of the Savvidy-Nielsen-Olesen (SNO) vacuum we make a systematic search for a stable magnetic background in pure SU(2) QCD. It is shown that Wu-Yang monopole-antimonopole pair is unstable under vacuum fluctuations. However, it is shown that a pair of axially symmetric monopole-antimonopole string configuration is stable, provided the distance between the two strings is small enough (less than a critical value). The existence of a stable monopole-antimonopole string background strongly supports that a magnetic condensation of monopole-antimonopole pairs can indeed generate a dynamical symmetry breaking, and thus a desired magnetic confinement of color, in QCD.

Y. M. Cho; D. G. Pak

2005-10-24T23:59:59.000Z

445

The Cosmic Microwave Background: Beyond the Power Spectrum  

E-Print Network [OSTI]

Much recent work on the cosmic microwave background (CMB) has focussed on the angular power spectrum of temperature anisotropies and particularly on the recovery of cosmological parameters from acoustic peaks in the power spectrum. However, there is more that can conceivably be done with CMB measurements. Here I briefly survey a few such ideas: cross-correlation with other cosmic backgrounds as a probe of the density of the Universe; CMB polarization as a gravitational-wave detector; secondary anisotropies and the ionization history of the Universe; tests of alternative-gravity theories; polarization, the Sunyaev-Zeldovich effect, and cosmic variance; and tests for a neutrino mass.

Marc Kamionkowski

1998-09-24T23:59:59.000Z

446

Stochastic Background Search Correlating ALLEGRO with LIGO Engineering Data  

E-Print Network [OSTI]

We describe the role of correlation measurements between the LIGO interferometer in Livingston, LA, and the ALLEGRO resonant bar detector in Baton Rouge, LA, in searches for a stochastic background of gravitational waves. Such measurements provide a valuable complement to correlations between interferometers at the two LIGO sites, since they are sensitive in a different, higher, frequency band. Additionally, the variable orientation of the ALLEGRO detector provides a means to distinguish gravitational wave correlations from correlated environmental noise. We describe the analysis underway to set a limit on the strength of a stochastic background at frequencies near 900 Hz using ALLEGRO data and data from LIGO's E7 Engineering Run.

John T Whelan; Edward Daw; Ik Siong Heng; Martin P McHugh; Albert Lazzarini

2003-08-14T23:59:59.000Z

447

Stochastic Background Search Correlating ALLEGRO with LIGO Engineering Data  

E-Print Network [OSTI]

We describe the role of correlation measurements between the LIGO interferometer in Livingston, LA, and the ALLEGRO resonant bar detector in Baton Rouge, LA, in searches for a stochastic background of gravitational waves. Such measurements provide a valuable complement to correlations between interferometers at the two LIGO sites, since they are sensitive in a different, higher, frequency band. Additionally, the variable orientation of the ALLEGRO detector provides a means to distinguish gravitational wave correlations from correlated environmental noise. We describe the analysis underway to set a limit on the strength of a stochastic background at frequencies near 900 Hz using ALLEGRO data and data from LIGO's E7 Engineering Run.

Whelan, J T; Heng, I S; McHugh, M P; Lazzarini, A; Whelan, John T; Daw, Edward; Heng, Ik Siong; Hugh, Martin P Mc; Lazzarini, Albert

2003-01-01T23:59:59.000Z

448

The Origin of the Extragalactic Gamma-Ray Background and Implications for Dark-Matter Annihilation  

E-Print Network [OSTI]

The origin of the extragalactic $\\gamma$-ray background (EGB) has been debated for some time. { The EGB comprises the $\\gamma$-ray emission from resolved and unresolved extragalactic sources, such as blazars, star-forming galaxies and radio galaxies, as well as radiation from truly diffuse processes.} This letter focuses on the blazar source class, the most numerous detected population, and presents an updated luminosity function and spectral energy distribution model consistent with the blazar observations performed by the {\\it Fermi} Large Area Telescope (LAT). We show that blazars account for 50$^{+12}_{-11}$\\,\\% of the EGB photons ($>$0.1\\,GeV), and that {\\it Fermi}-LAT has already resolved $\\sim$70\\,\\% of this contribution. Blazars, and in particular low-luminosity hard-spectrum nearby sources like BL Lacs, are responsible for most of the EGB emission above 100\\,GeV. We find that the extragalactic background light, which attenuates blazars' high-energy emission, is responsible for the high-energy cut-off...

Ajello, M; Sanchez-Conde, M; Zaharijas, G; Gustafsson, M; Cohen-Tanugi, J; Dermer, C D; Inoue, Y; Hartmann, D; Ackermann, M; Bechtol, K; Franckowiak, A; Reimer, A; Romani, R W; Strong, A W

2015-01-01T23:59:59.000Z

449

ADAPTIVE RADIATION ROSEMARY G. GILLESPIE  

E-Print Network [OSTI]

1 A ADAPTIVE RADIATION ROSEMARY G. GILLESPIE University of California, Berkeley Adaptive radiation- tions and convergence of species groups on different land masses. Since then, adaptive radiation has diversity within a rapidly multiplying lineage." There are radiations that are not adaptive

Gillespie, Rosemary

450

REPORT NO. 8 radiation hazards  

E-Print Network [OSTI]

REPORT NO. 8 REVISED guidance for the control of radiation hazards in uranium mining SEPTEMBER 1967 OF RADIATION HAZARDS IN URANIUM MINING SEPTEMBER 1967 Staff Report of the FEDERAL RADIATION COUNCIL #12;FEDERAL...... .... .._ _.... Section I. Introduction. . . Section II. The Radiation Environment AssociatedWith Uranium Mining. Section

451

Appendix G: Radiation HYDROGEN ATOM  

E-Print Network [OSTI]

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix G: Radiation #12;#12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

452

Appendix A: Radiation HYDROGEN ATOM  

E-Print Network [OSTI]

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix A: Radiation #12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

453

A Radiation Hardened Reconfigurable FPGA Shankarnarayanan Ramaswamy1  

E-Print Network [OSTI]

Size Isolation Device Options S/D Engineering Supply Voltages Gate Electrodes Metal Levels Poly & Diffusion Silicide 150nm Shallow Trench Isolation 26 Ã? / 70 Ã? Halo with S/D Extensions 1.5V / 3.3V N+ Poly and manufactured utilizing this 150 nm radiation hardened CMOS process employing seven levels of metal. The chip

Manohar, Rajit

454

Project Background Transportation projects can stall for a number of  

E-Print Network [OSTI]

Project Background Transportation projects can stall for a number of reasons. One reason is that those responsible for the project lack the skills to move beyond conflicts with resource agency staff work on a pilot program aimed at confronting these two causes. The project had these objectives

Minnesota, University of

455

3.5 Nanowire Sensors 3.5.1 Background  

E-Print Network [OSTI]

117 3.5 Nanowire Sensors 3.5.1 Background Nanowires are solid, rod-like materials with diameters that similar commercial products will eventually be available. 3.5.2 Description Nanowire sensors have et al. 2003). A comprehensive review of current research activities on chemical sensors based

456

STRING LOOPS IN BACKGROUND FIELDS Scott Alan Yost  

E-Print Network [OSTI]

excellent collaborators. They have made my stay at Princeton very productive and enjoyable. I thank E. LiebSTRING LOOPS IN BACKGROUND FIELDS Scott Alan Yost A dissertation presented to the faculty formalism. ii #12;Acknowledgements I would like to thank my advisor, Chiara Nappi, for her support, advice

Yost, Scott

457

ECONOMICS OF AGRICULTURE AND WILDLIFE A Background Report on the  

E-Print Network [OSTI]

a system of economic incentives and develop cost effective solutions to agricultural and wildlife issues#12;ECONOMICS OF AGRICULTURE AND WILDLIFE A Background Report on the Potential for Use of Economic and Associated Floodplains prepared by Richard M. Porter for Socio-Economic Section Sustainability Division

458

Amphibian Decline or Extinction? Current Declines Dwarf Background Extinction Rate  

E-Print Network [OSTI]

the background amphibian extinction rate. If current estimates of amphibian species in imminent danger). Although it is thought that 35 species of amphibians have gone extinct since 1500, this number may). Another 1,896 species may be in imminent danger of extinction (IUCN et al., 2006). All of these estimates

McCallum, Malcolm

459

Compressed Gas Cylinder Safety I. Background. Due to the nature  

E-Print Network [OSTI]

Compressed Gas Cylinder Safety I. Background. Due to the nature of gas cylinders hazards of a ruptured cylinder. There are almost 200 different types of materials in gas cylinders, there are several general procedures to follow for safe storage and handling of a compressed gas cylinder: II

Suzuki, Masatsugu

460

1 Background 1.1 Topic of research  

E-Print Network [OSTI]

1 Background 1.1 Topic of research Mathematical quantitative tools (like probabil- ity theory analyses on the basis of these meth- ods. 1.2 Academic and industrial con- text Interference in a security section 1.3). Applications of this work can be found in large scale, mission critical, security related

Hunt, Sebastian

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461

Background Suppression in Near-Field Optical Imaging  

E-Print Network [OSTI]

irradiation of the optical antenna (e.g., tip or particle) also directly irradiates the sample and thereforeBackground Suppression in Near-Field Optical Imaging Christiane Ho¨ppener, Ryan Beams, and Lukas Novotny* Institute of Optics, UniVersity of Rochester, Rochester, New York 14627 Received December 25

Novotny, Lukas

462

Statistical Isotropy of the Cosmic Microwave Background Anisotropy  

E-Print Network [OSTI]

Statistical Isotropy of the Cosmic Microwave Background Anisotropy Amir Hajian #3; I.U.C.A.A., Pune to be statistically isotropic, i.e., statistical expectation values of the temperature #29;uctuations are preserved under rotations of the sky. Only under statistical isotropy does the widely used angular power spectrum

Souradeep, Tarun

463

Power Systems Engineering Research Center PSERC Background Paper  

E-Print Network [OSTI]

Power Systems Engineering Research Center PSERC Background Paper Power System Operations of Illinois at Urbana-Champaign September 10, 2003 Before the August 14th 2003 blackout most people gave little thought to the source of the power that comes out of the electric outlet. And why should they

464

Optimal coherent control of CARS: signal enhancement and background elimination  

E-Print Network [OSTI]

The ability to enhance resonant signals and eliminate the non-resonant background is analyzed for Coherent Anti-Stokes Raman Scattering (CARS). The analysis is done at a specific frequency as well as for broadband excitation using femtosecond pulse-shaping techniques. An appropriate objective functional is employed to balance resonant signal enhancement against non-resonant background suppression. Optimal enhancement of the signal and minimization of the background can be achieved by shaping the probe pulse alone while keeping the pump and Stokes pulses in transform-limited-form (TLF). In some cases analytical forms for the probe pulse can be found, and numerical simulations are carried out for other circumstances. It is found that a good approximate solution for the optimal pulse in the two-pulse CARS is a superposition of linear and arctangent type phases for the pump. The well-known probe delay method is shown to be a quasi-optimal scheme for background suppression. The results should provide a basis to improve the performance of CARS spectroscopy and microscopy.

Fang Gao; Feng Shuang; JunHui Shi; Herschel Rabitz; HaiFeng Wang; JiXin Cheng

2012-03-28T23:59:59.000Z

465

Power Systems Engineering Research Center PSERC Background Paper  

E-Print Network [OSTI]

Power Systems Engineering Research Center PSERC Background Paper What is Reactive Power? Peter W-Champaign September 16, 2003 Engineering talk Reactive power is a quantity that is normally only defined time). In that sense, these are pulsating quantities. Because of this, the power being transmitted down

466

Cosmic and Galactic Neutrino Backgrounds from Thermonuclear Sources  

E-Print Network [OSTI]

We estimate energy spectra and fluxes at the Earth's surface of the cosmic and Galactic neutrino backgrounds produced by thermonuclear reactions in stars. The extra-galactic component is obtained by combining the most recent estimates of the cosmic star formation history and the stellar initial mass function with accurate theoretical predictions of the neutrino yields all over the thermonuclear lifetime of stars of different masses. Models of the structure and evolution of the Milky Way are used to derive maps of the expected flux generated by Galactic sources as a function of sky direction. The predicted neutrino backgrounds depend only slightly on model parameters. In the relevant 50 keV-10 MeV window, the total flux of cosmic neutrinos ranges between 20 and 65 particles per square cm per s. Neutrinos reaching the Earth today have been typically emitted at redshift z~2. Their energy spectrum peaks at E~0.1-0.3 MeV. The energy and entropy densities of the cosmic background are negligible with respect to the thermal contribution of relic neutrinos originated in the early universe. In every sky direction, the cosmic background is outnumbered by the Galactic one, whose integrated flux amounts to 300-1000 particles per square cm per s. The emission from stars in the Galactic disk contributes more than 95 per cent of the signal.

Cristiano Porciani; Silvia Petroni; Giovanni Fiorentini

2003-11-20T23:59:59.000Z

467

The prospects for polarized target materials with pure carbon background  

SciTech Connect (OSTI)

None of the materials presently in common use for polarized proton targets has a pure carbon nuclear background. The alcohols and diols contain some oxygen, and the ammonia and amine-based materials contain nitrogen and/or other noncarbon species. In the latter cases the noncarbon nuclei are measurably polarized as a concomitant of the process used to polarize the hydrogen nuclei. The relative simplicity of a pure carbon background would be advantageous for most types of scattering experiments and perhaps crucial for some. In addition to simplifying the kinematics of background events, pure carbon is relatively easy to prepare as a ``dummy`` target for background subtraction. Also, in such a target material, {sup 13}C-enrichment would yield a clean polarized {sup 13}C material. In this note I explore the possibilities for such materials, touching upon only what I consider to be the ``high`` points. The subject matter is capable of nearly endless ramification and speculation. In fact, owing to a general lack of relevant experimental data, even this relatively brief note contains much that is speculative to some degree.

Hill, D.A.

1992-10-06T23:59:59.000Z

468

The prospects for polarized target materials with pure carbon background  

SciTech Connect (OSTI)

None of the materials presently in common use for polarized proton targets has a pure carbon nuclear background. The alcohols and diols contain some oxygen, and the ammonia and amine-based materials contain nitrogen and/or other noncarbon species. In the latter cases the noncarbon nuclei are measurably polarized as a concomitant of the process used to polarize the hydrogen nuclei. The relative simplicity of a pure carbon background would be advantageous for most types of scattering experiments and perhaps crucial for some. In addition to simplifying the kinematics of background events, pure carbon is relatively easy to prepare as a dummy'' target for background subtraction. Also, in such a target material, [sup 13]C-enrichment would yield a clean polarized [sup 13]C material. In this note I explore the possibilities for such materials, touching upon only what I consider to be the high'' points. The subject matter is capable of nearly endless ramification and speculation. In fact, owing to a general lack of relevant experimental data, even this relatively brief note contains much that is speculative to some degree.

Hill, D.A.

1992-10-06T23:59:59.000Z

469

Rev. January 30, 2012 1 REFERENCE and BACKGROUND CHECK  

E-Print Network [OSTI]

Rev. January 30, 2012 1 REFERENCE and BACKGROUND CHECK PROCESS HUMAN RESOURCES Workforce Planning, as allowed by law, and consistent with the job described. The appropriate Workforce Planning Analyst the documentation. (Please note that the review will take place in Human Resources, under a Workforce Planning

Eirinaki, Magdalini

470

Power Systems Engineering Research Center PSERC Background Paper  

E-Print Network [OSTI]

Power Systems Engineering Research Center PSERC Background Paper The New Electric Power Business-tuned, economically efficient, and technically-reliable electric power system. The creation of new information system is outmoded and unprepared for the challenges of the new electric power business. A result

471

Seeing is Believing: It's All About the Background  

E-Print Network [OSTI]

Seeing is Believing: It's All About the Background Thomas Meade Eileen Foell Chair in Cancer may promise for the experimental and clinical settings. Speaker Bio Thomas Meade, Ph.D., Received BS of Technology in the laboratory of Professor Harry B. Gray. In 1991 he joined the Division of Biology

Zanibbi, Richard

472

A method for enhancement of background sounds in forensic  

E-Print Network [OSTI]

A method for enhancement of background sounds in forensic audio recordings Robert C. Maher;Outline · Introduction ­ Audio forensic analysis ­ Adaptive interference cancelling ­ Sinusoidal modeling · Test implementation · Example processing · Conclusion #12;Audio Forensics · Audio Forensics

Maher, Robert C.

473

Issues in Low Dose Radiation Biology: The Controversy Continues. A Perspective  

SciTech Connect (OSTI)

Both natural and man-made sources of ionizing radiation contribute to human exposure and consequently pose a risk to human health. Much of this is unavoidable, e.g., natural background radiation, and as the use of radiation in modern medicine and industry increases so does the potential health risk. This perspective reflects the author’s view of current issues in low dose radiation biology research, highlights some of the controversies therein, and suggests areas of future research to address these issues. The views expressed here are the authors own and do not represent any institution, organization or funding body.

Morgan, William F.; Bair, William J.

2013-05-01T23:59:59.000Z

474

Radiative Feedback in Relic HII Regions at High-Redshift  

E-Print Network [OSTI]

UV radiation from early astrophysical sources could have a large impact on subsequent star formation in nearby protogalaxies. Here we study the radiative feedback from the first, short-lived stars using hydrodynamical simulations with transient UV backgrounds (UVBs) and persistent Lyman-Werner backgrounds (LWBs) of varying intensity. We extend our prior work in Mesinger et al. (2006), by studying a more typical region whose proto-galaxies form at lower redshifts, z~13-20, in the epoch likely preceding the bulk of reionization. We confirm our previous results that feedback in the relic HII regions resulting from such transient radiation, is itself transient. Feedback effects dwindle away after ~30% of the Hubble time, and the same critical specific intensity of J_UV~0.1 x 10^{-21} ergs/s/cm^2/Hz/sr separates positive and negative feedback regimes. Additionally, we discover a second episode of eventual positive feedback in halos which have not yet collapsed when their progenitor regions were exposed to the transient UVB. This eventual positive feedback appears in all runs, regardless of the strength of the UVB. However, this feedback regime is very sensitive to the presence of Lyman-Werner radiation, and notable effects disappear under fairly modest background intensities of J_LW>10^{-3} x 10^{-21} ergs/s/cm^2/Hz/sr. We conclude that UV radiative feedback in relic HII regions, although a complicated process, seems unlikely to have a major impact on the progress of cosmological reionization, provided that present estimates of the lifetime and luminosity of a PopIII star are accurate. More likely is that the build-up of the LWB ultimately governs the feedback strength until a persistent UV background can be established. [abridged

Andrei Mesinger; Greg L. Bryan; Zoltan Haiman

2009-09-13T23:59:59.000Z

475

Radiation delivery system and method  

DOE Patents [OSTI]

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.

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

476

Mechanisms of radiation interaction with DNA: Potential implications for radiation protection  

SciTech Connect (OSTI)

The Office of Health and Environmental Research (OHER) of the US Department of Energy conducts a broad multidisciplinary research program which includes basic biophysics, biophysical chemistry, molecular and cellular biology as well as experimental animal studies and opportunistic human studies. This research is directed at understanding how low levels of radiation of various qualities produce the spectrum of biological effects that are seen for such exposures. This workshop was entitled ''Mechanisms of Radiation Interaction with DNA: Potential Implications for Radiation Protection.'' It ws jointly sponsored by the Department of Energy and the Commission of European Communities. The aim of the workshop was to review the base of knowledge in the area of mechanisms of radiation action at the DNA level, and to explore ways in which this information can be applied to the development of scientifically sound concepts and procedures for use in the field of radiation protection. The overview of research provided by this multidisciplinary group will be helpful to the Office in program planning. This report includes a summary of the presentations, extended abstracts, the meeting agenda, research recommendations, and a list of participants. Individual papers are processed separately for the data base.

Not Available

1988-01-01T23:59:59.000Z

477

Packet personal radiation monitor  

DOE Patents [OSTI]

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.

Phelps, J.E.

1988-03-31T23:59:59.000Z

478

Technical support for amending standards for management of uranium byproduct materials: 40 cfr part 192-subpart d. Background information document  

SciTech Connect (OSTI)

The Environmental Protection Agency (EPA) is amending 40 CFR 192, Subpart D, dealing with disposal of uranium mill tailings at non-operational sites licensed by the Nuclear Regulatory Commission (NRC) or an agreement state pursuant to the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978. The Background Information Document (BID) was prepared in support of the rulemaking proceedings for EPA's action. The BID only considers long-term disposal of tailings at facilities licensed by the NRC or an agreement state, and designated Title II facilities in the UMTRCA.

Not Available

1993-10-01T23:59:59.000Z

479

Application of Improved Radiation Modeling to General Circulation Models  

SciTech Connect (OSTI)

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.

Michael J Iacono

2011-04-07T23:59:59.000Z

480

THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): A SOUNDING ROCKET PAYLOAD TO STUDY THE NEAR INFRARED EXTRAGALACTIC BACKGROUND LIGHT  

SciTech Connect (OSTI)

The Cosmic Infrared Background Experiment (CIBER) is a suite of four instruments designed to study the near infrared (IR) background light from above the Earth's atmosphere. The instrument package comprises two imaging telescopes designed to characterize spatial anisotropy in the extragalactic IR background caused by cosmological structure during the epoch of reionization, a low resolution spectrometer to measure the absolute spectrum of the extragalactic IR background, and a narrow band spectrometer optimized to measure the absolute brightness of the zodiacal light foreground. In this paper we describe the design and characterization of the CIBER payload. The detailed mechanical, cryogenic, and electrical design of the system are presented, including all system components common to the four instruments. We present the methods and equipment used to characterize the instruments before and after flight, and give a detailed description of CIBER's flight profile and configurations. CIBER is designed to be recoverable and has flown four times, with modifications to the payload having been informed by analysis of the first flight data. All four instruments performed to specifications during the subsequent flights, and the scientific data from these flights are currently being analyzed.

Zemcov, M.; Bock, J.; Hristov, V.; Levenson, L. R.; Mason, P. [Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Arai, T.; Matsumoto, T.; Matsuura, S.; Tsumura, K.; Wada, T. [Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Battle, J. [Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109 (United States); Cooray, A. [Center for Cosmology, University of California, Irvine, Irvine, CA 92697 (United States); Keating, B.; Renbarger, T. [Department of Physics, University of California, San Diego, San Diego, CA 92093 (United States); Kim, M. G. [Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, D. H.; Nam, U. W. [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of); Sullivan, I. [Department of Physics, The University of Washington, Seattle, WA 98195 (United Sta