Sandia National Laboratories: Research: Research Foundations: Radiation

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Effects and High Energy Density Science Sandia National Laboratories Exceptional service in the Engineering Science Geoscience Materials Science Nanodevices & Microsystems Radiation Effects & High Science Geoscience Materials Science Nanodevices and Microsystems Radiation Effects and High Energy

Mitigation of Earth-asteroid collisions via explosive, intense radiation sources

NASA Astrophysics Data System (ADS)

Miles, Aaron; Sanders, James

2005-10-01

The Universe is continually producing astrophysical explosions that generate intense bursts of electromagnetic and particle radiation. Interaction of this radiation with nearby objects can effect significant changes to their dynamics through a variety of processes including ionization, ablation, and shock generation. The next time a large asteroid or comet is found to be approaching the Earth on an impact trajectory, humans may find it prudent to mimic nature by using the most intense radiation sources available to alter the incoming object's trajectory and avert a catastrophic collision. With this in mind, we consider the effect of nuclear explosives on nearby would-be Earth impactors. Neutrons and x-rays produced in the explosion are deposited in a thin layer of the asteroid's surface, resulting in ablation and shock and thereby imparting a deflection velocity. A Monte Carlo code is used for radiation transport and energy deposition, while the subsequent dynamic evolution of the asteroid is followed with the hydrodynamics code CALE. We consider the dependence of the deflection velocity on the source energy and spectrum, the asteroid or comet composition, and the standoff distance between the target and the source. This work was performed under the auspices of the U. S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

A source-attractor approach to network detection of radiation sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Qishi; Barry, M. L..; Grieme, M.

Radiation source detection using a network of detectors is an active field of research for homeland security and defense applications. We propose Source-attractor Radiation Detection (SRD) method to aggregate measurements from a network of detectors for radiation source detection. SRD method models a potential radiation source as a magnet -like attractor that pulls in pre-computed virtual points from the detector locations. A detection decision is made if a sufficient level of attraction, quantified by the increase in the clustering of the shifted virtual points, is observed. Compared with traditional methods, SRD has the following advantages: i) it does not requiremore » an accurate estimate of the source location from limited and noise-corrupted sensor readings, unlike the localizationbased methods, and ii) its virtual point shifting and clustering calculation involve simple arithmetic operations based on the number of detectors, avoiding the high computational complexity of grid-based likelihood estimation methods. We evaluate its detection performance using canonical datasets from Domestic Nuclear Detection Office s (DNDO) Intelligence Radiation Sensors Systems (IRSS) tests. SRD achieves both lower false alarm rate and false negative rate compared to three existing algorithms for network source detection.« less

76 FR 6692 - Radiation Sources on Army Land

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-08

...-AA58 Radiation Sources on Army Land AGENCY: Department of the Army, DoD. ACTION: Final rule. SUMMARY: The Department of the Army is finalizing revisions to its regulation concerning radiation sources on... Radiation Permit (ARP) from the garrison commander to use, store, or possess ionizing radiation sources on...

Calibration of Radiation Thermometers up to : Effective Emissivity of the Source

NASA Astrophysics Data System (ADS)

Kozlova, O.; Briaudeau, S.; Rongione, L.; Bourson, F.; Guimier, S.; Kosmalski, S.; Sadli, M.

2015-08-01

The growing demand of industry for traceable temperature measurements up to encourages improvement of calibration techniques for industrial-type radiation thermometers in this temperature range. High-temperature fixed points can be used at such high temperatures, but due to the small diameter of apertures of their cavities (3 mm), they are not adapted for the large field-of-views commonly featured by this kind of radiation thermometers. At LNE-Cnam, a Thermo Gauge furnace of 25.4 mm source aperture diameter is used as a comparison source to calibrate customers' instruments against a reference radiation thermometer calibrated according to the ITS-90 with the lowest uncertainties achievable in the Laboratory. But the furnace blackbody radiator exhibits a large temperature gradient that degrades its effective emissivity, and increases the calibration uncertainty due to the lack of information on the working spectral band of the industrial radiation thermometer. In order to estimate the corrections to apply, the temperature distribution (radial and on-axis) of the Thermo Gauge furnace blackbody radiator was characterized and the effective emissivity of the Thermo Gauge cavity was determined by three different methods. Because of this investigation, the corrections due to different fields of view and due to the different spectral bands of the reference pyrometer and the customer's pyrometer were obtained and the uncertainties on these corrections were evaluated.

[Radiation safety of exploitation of radiation sources at the civil aviation airlines].

PubMed

Afanas'ev, R V; Zuev, V G; Berezin, G I; Sereda, V N; Zasiad'ko, A K

2004-01-01

Radiation risks from isotope-containing equipment, and ionizing and unused X-ray radiation sources are characterized and relevant normative documents with safety requirements to radiation sources installation, radiation safety of aircraft servicing and repair, hand luggage control and heavy luggage registration, personal protection items, system of radiation monitoring at airlines and aircraft works, and liability for breach of performance guidelines are cited.

Radiation source with shaped emission

DOEpatents

Kubiak, Glenn D.; Sweatt, William C.

2003-05-13

Employing a source of radiation, such as an electric discharge source, that is equipped with a capillary region configured into some predetermined shape, such as an arc or slit, can significantly improve the amount of flux delivered to the lithographic wafers while maintaining high efficiency. The source is particularly suited for photolithography systems that employs a ringfield camera. The invention permits the condenser which delivers critical illumination to the reticle to be simplified from five or more reflective elements to a total of three or four reflective elements thereby increasing condenser efficiency. It maximizes the flux delivered and maintains a high coupling efficiency. This architecture couples EUV radiation from the discharge source into a ring field lithography camera.

21 CFR 886.5100 - Ophthalmic beta radiation source.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ophthalmic beta radiation source. 886.5100 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5100 Ophthalmic beta radiation source. (a) Identification. An ophthalmic beta radiation source is a device intended to apply superficial...

21 CFR 886.5100 - Ophthalmic beta radiation source.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ophthalmic beta radiation source. 886.5100 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5100 Ophthalmic beta radiation source. (a) Identification. An ophthalmic beta radiation source is a device intended to apply superficial...

21 CFR 886.5100 - Ophthalmic beta radiation source.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ophthalmic beta radiation source. 886.5100 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5100 Ophthalmic beta radiation source. (a) Identification. An ophthalmic beta radiation source is a device intended to apply superficial...

21 CFR 886.5100 - Ophthalmic beta radiation source.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ophthalmic beta radiation source. 886.5100 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5100 Ophthalmic beta radiation source. (a) Identification. An ophthalmic beta radiation source is a device intended to apply superficial...

21 CFR 886.5100 - Ophthalmic beta radiation source.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ophthalmic beta radiation source. 886.5100 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5100 Ophthalmic beta radiation source. (a) Identification. An ophthalmic beta radiation source is a device intended to apply superficial...

Modeling and Laboratory Investigations of Radiative Shocks

NASA Astrophysics Data System (ADS)

Grun, Jacob; Laming, J. Martin; Manka, Charles; Moore, Christopher; Jones, Ted; Tam, Daniel

2001-10-01

Supernova remnants are often inhomogeneous, with knots or clumps of material expanding in ambient plasma. This structure may be initiated by hydrodynamic instabilities occurring during the explosion, but it may plausibly be amplified by instabilities of the expanding shocks such as, for example, corrugation instabilities described by D’yakov in 1954, Vishniac in 1983, and observed in the laboratory by Grun et al. in 1991. Shock instability can occur when radiation lowers the effective adiabatic index of the gas. In view of the difficulty of modeling radiation in non-equilibrium plasmas, and the dependence of shock instabilities on such radiation, we are performing a laboratory experiment to study radiative shocks. The shocks are generated in a miniature, laser-driven shock tube. The gas density inside the tube at any instant in time is measured using time and space-resolved interferometry, and the emission spectrum of the gas is measured with time-resolved spectroscopy. We simulate the experiment with a 1D code that models time dependent post-shock ionization and non-equilibrium radiative cooling. S. P. D’yakov, Zhurnal Eksperimentalnoi Teoreticheskoi Fiziki 27, 288 (1954); see also section 90 in L.D. Landau and E.M. Lifshitz, Fluid Mechanics (Butterworth-Heinemann 1987); E.T. Vishniac, Astrophys. J. 236, 880 (1983); J. Grun, et al., Phys. Rev. Lett., 66, 2738 (1991)

Samarium-145 and its use as a radiation source

DOEpatents

Fairchild, Ralph G.; Laster, Brenda H.; Packer, Samuel

1989-09-05

The present invention covers a new radiation source, samarium-145, with radiation energies slightly above those of I-125 and a half-life of 340 days. The samarium-145 source is produced by neutron irradiation of SM-144. This new source is useful as the implanted radiation source in photon activation therapy of malignant tumors to activate the stable I-127 contained in the IdUrd accumulated in the tumor, causing radiation sensitization and Auger cascades that irreperably damage the tumor cells. This new source is also useful as a brachytherapy source.

Samarium-145 and its use as a radiation source

DOEpatents

Fairchild, Ralph G.; Laster, Brenda H.; Packer, Samuel

1989-01-01

The present invention covers a new radiation source, samarium-145, with radiation energies slightly above those of I-125 and a half-life of 340 days. The samarium-145 source is produced by neutron irradiation of SM-144. This new source is useful as the implanted radiation source in photon activation therapy of malignant tumors to activate the stable I-127 contained in the IdUrd accumulated in the tumor, causing radiation sensitization and Auger cascades that irreperably damage the tumor cells. This new source is also useful as a brachytherapy source.

Application and development of ion-source technology for radiation-effects testing of electronics

NASA Astrophysics Data System (ADS)

Kalvas, T.; Javanainen, A.; Kettunen, H.; Koivisto, H.; Tarvainen, O.; Virtanen, A.

2017-09-01

Studies of heavy-ion induced single event effect (SEE) on space electronics are necessary to verify the operation of the components in the harsh radiation environment. These studies are conducted by using high-energy heavy-ion beams to simulate the radiation effects in space. The ion beams are accelerated as so-called ion cocktails, containing several ion beam species with similar mass-to-charge ratio, covering a wide range of linear energy transfer (LET) values also present in space. The use of cocktails enables fast switching between beam species during testing. Production of these high-energy ion cocktails poses challenging requirements to the ion sources because in most laboratories reaching the necessary beam energies requires very high charge state ions. There are two main technologies producing these beams: The electron beam ion source EBIS and the electron cyclotron resonance ion source ECRIS. The EBIS is most suitable for pulsed accelerators, while ECRIS is most suitable for use with cyclotrons, which are the most common accelerators used in these applications. At the Accelerator Laboratory of the University of Jyväskylä (JYFL), radiation effects testing is currently performed using a K130 cyclotron and a 14 GHz ECRIS at a beam energy of 9.3 MeV/u. A new 18 GHz ECRIS, pushing the limits of the normal conducting ECR technology is under development at JYFL. The performances of existing 18 GHz ion sources have been compared, and based on this analysis, a 16.2 MeV/u beam cocktail with 1999 MeV 126Xe44+ being the most challenging component to has been chosen for development at JYFL. The properties of the suggested beam cocktail are introduced and discussed.

Radiation and Health Technology Laboratory Capabilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bihl, Donald E.; Lynch, Timothy P.; Murphy, Mark K.

2005-07-09

The Radiological Standards and Calibrations Laboratory, a part of Pacific Northwest National Laboratory (PNNL)(a) performs calibrations and upholds reference standards necessary to maintain traceability to national standards. The facility supports U.S. Department of Energy (DOE) programs at the Hanford Site, programs sponsored by DOE Headquarters and other federal agencies, radiological protection programs at other DOE and commercial nuclear sites and research and characterization programs sponsored through the commercial sector. The laboratory is located in the 318 Building of the Hanford Site's 300 Area. The facility contains five major exposure rooms and several laboratories used for exposure work preparation, low-activity instrumentmore » calibrations, instrument performance evaluations, instrument maintenance, instrument design and fabrication work, thermoluminescent and radiochromic Dosimetry, and calibration of measurement and test equipment (M&TE). The major exposure facilities are a low-scatter room used for neutron and photon exposures, a source well room used for high-volume instrument calibration work, an x-ray facility used for energy response studies, a high-exposure facility used for high-rate photon calibration work, a beta standards laboratory used for beta energy response studies and beta reference calibrations and M&TE laboratories. Calibrations are routinely performed for personnel dosimeters, health physics instrumentation, photon and neutron transfer standards alpha, beta, and gamma field sources used throughout the Hanford Site, and a wide variety of M&TE. This report describes the standards and calibrations laboratory.« less

75 FR 19302 - Radiation Sources on Army Land

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-14

... Nuclear Regulatory Commission (NRC) license or Army Radiation Authorization (ARA). The purpose of the ARP...-0001] Radiation Sources on Army Land AGENCY: Department of the Army, DoD. ACTION: Proposed rule... radiation sources on Army land. The Army requires Non-Army agencies (including their civilian contractors...

Indirect detection of radiation sources through direct detection of radiolysis products

DOEpatents

Farmer, Joseph C [Tracy, CA; Fischer, Larry E [Los Gatos, CA; Felter, Thomas E [Livermore, CA

2010-04-20

A system for indirectly detecting a radiation source by directly detecting radiolytic products. The radiation source emits radiation and the radiation produces the radiolytic products. A fluid is positioned to receive the radiation from the radiation source. When the fluid is irradiated, radiolytic products are produced. By directly detecting the radiolytic products, the radiation source is detected.

Finite Source Inversion for Laboratory Earthquakes

NASA Astrophysics Data System (ADS)

Parker, J. M.; Glaser, S. D.

2017-12-01

We produce finite source inversion results for laboratory earthquakes (LEQ) in PMMA confirmed by video recording of the fault contact. The LEQs are generated under highly controlled laboratory conditions and recorded by an array of absolutely calibrated acoustic emissions (AE) sensors. Following the method of Hartzell and Heaton (1983), we develop a solution using only the single-component AE sensors common in laboratory experiments. A set of calibration tests using glass capillary sources of varying size resolves the material characteristics and synthetic Green's Functions such that uncertainty in source location is reduced to 3σ<1mm; typical source radii are 1mm. Well-isolated events with corner frequencies on the order of 0.1 MHz (Mw -6) are recorded at 20 MHz and initially band-pass filtered from 0.1 to 1.0 MHz; in comparison, large earthquakes with corner frequencies around 0.1 Hz are commonly filtered from 0.1 to 1.0 Hz. We compare results of the inversion and video recording to slip distribution predicted by the Cattaneo partial slip asperity and numerical modeling. Not all asperities are large enough to resolve individually so some results must be interpreted as the smoothed effects of clusters of tiny contacts. For large asperities, partial slip is observed originating at the asperity edges and moving inward as predicted by the theory. Furthermore, expanding shear rupture fronts are observed as they reach resistive patches of asperities and halt or continue, depending on the relative energies of rupture and resistance.

Plasma x-ray radiation source.

PubMed

Popkov, N F; Kargin, V I; Ryaslov, E A; Pikar', A S

1995-01-01

This paper gives the results of studies on a plasma x-ray source, which enables one to obtain a 2.5-krad radiation dose per pulse over an area of 100 cm2 in the quantum energy range from 20 to 500 keV. Pulse duration is 100 ns. Spectral radiation distributions from a diode under various operation conditions of a plasma are obtained. A Marx generator served as an initial energy source of 120 kJ with a discharge time of T/4 = 10-6 s. A short electromagnetic pulse (10-7 s) was shaped using plasma erosion opening switches.

Power source evaluation capabilities at Sandia National Laboratories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doughty, D.H.; Butler, P.C.

1996-04-01

Sandia National Laboratories maintains one of the most comprehensive power source characterization facilities in the U.S. National Laboratory system. This paper describes the capabilities for evaluation of fuel cell technologies. The facility has a rechargeable battery test laboratory and a test area for performing nondestructive and functional computer-controlled testing of cells and batteries.

Galactic Cosmic Ray Simulator at the NASA Space Radiation Laboratory

NASA Technical Reports Server (NTRS)

Norbury, John W.; Slaba, Tony C.; Rusek, Adam

2015-01-01

The external Galactic Cosmic Ray (GCR) spectrum is significantly modified when it passes through spacecraft shielding and astronauts. One approach for simulating the GCR space radiation environment is to attempt to reproduce the unmodified, external GCR spectrum at a ground based accelerator. A possibly better approach would use the modified, shielded tissue spectrum, to select accelerator beams impinging on biological targets. NASA plans for implementation of a GCR simulator at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory will be discussed.

[Use of ionizing radiation sources in metallurgy: risk assessment].

PubMed

Giugni, U

2012-01-01

Use of ionizing radiation sources in the metallurgical industry: risk assessment. Radioactive sources and fixed or mobile X-ray equipment are used for both process and quality control. The use of ionizing radiation sources requires careful risk assessment. The text lists the characteristics of the sources and the legal requirements, and contains a description of the documentation required and the methods used for risk assessment. It describes how to estimate the doses to operators and the relevant classification criteria used for the purpose of radiation protection. Training programs must be organized in close collaboration between the radiation protection expert and the occupational physician.

Cathodoluminescent UV-radiation sources

NASA Astrophysics Data System (ADS)

Vereschagina, N. Y.; Danilkin, M. I.; Kazaryan, M. A.; Ozol, D. I.; Sheshin, E. P.; Spassky, D. A.

2018-04-01

Mercury-free UV-radiation sources are described. An electron beam similar to cathode-ray tubes (CRT) excites a luminescent material in a vacuum bulb. A high density of excitation requires the cathode and the luminescent material to be resistant for that and provide the extended lifetime of the UV-radiation source. Carbon fibre and nano-carbon based field-emission cathodes produce long lasting stable emission with a high current density (up to 0.3-0.5 A/cm2 ). Li2B4O7:Cu and Li2B4O7:Ag luminescent ceramics survive under high radiation doses and provide UV luminescence bands peaked at 360-370 nm and 270 nm, respectively. The luminescence band at 360-370 nm has a good overlap with the fundamental absorption edge of TiO2, which is known as a photo-catalyst in air and water cleaning systems. The luminescence band at 270 nm overlaps with DNA absorption and provides a direct disinfection effect. We suggest the structure of complex luminescence centres and energy transfer mechanisms. The electron structure of lithium tetraborate and the contribution of impurities are also discussed in paper.

Organic Materials Ionizing Radiation Susceptibility for the Outer Planet/Solar Probe Radioisotope Power Source

NASA Technical Reports Server (NTRS)

Golliher, Eric L.; Pepper, Stephen V.

2001-01-01

The Department of Energy is considering the current Stirling Technology Corporation 55 We Stirling Technology Demonstration Convertor as a baseline option for an advanced radioisotope power source for the Outer Planets/Solar Probe project of Jet Propulsion Laboratory and other missions. However, since the Technology Demonstration Convertor contains organic materials chosen without any special consideration of flight readiness, and without any consideration of the extremely high radiation environment of Europa, a preliminary investigation was performed to address the radiation susceptibility of the current organic materials used in the Technology Demonstration Convertor. This report documents the results of the investigation. The results of the investigation show that candidate replacement materials have been identified to be acceptable in the harsh Europa radiation environment.

Optical Imaging of Ionizing Radiation from Clinical Sources

PubMed Central

Shaffer, Travis M.; Drain, Charles Michael

2016-01-01

Nuclear medicine uses ionizing radiation for both in vivo diagnosis and therapy. Ionizing radiation comes from a variety of sources, including x-rays, beam therapy, brachytherapy, and various injected radionuclides. Although PET and SPECT remain clinical mainstays, optical readouts of ionizing radiation offer numerous benefits and complement these standard techniques. Furthermore, for ionizing radiation sources that cannot be imaged using these standard techniques, optical imaging offers a unique imaging alternative. This article reviews optical imaging of both radionuclide- and beam-based ionizing radiation from high-energy photons and charged particles through mechanisms including radioluminescence, Cerenkov luminescence, and scintillation. Therapeutically, these visible photons have been combined with photodynamic therapeutic agents preclinically for increasing therapeutic response at depths difficult to reach with external light sources. Last, new microscopy methods that allow single-cell optical imaging of radionuclides are reviewed. PMID:27688469

Optical radiation measurements: instrumentation and sources of error.

PubMed

Landry, R J; Andersen, F A

1982-07-01

Accurate measurement of optical radiation is required when sources of this radiation are used in biological research. The most difficult measurements of broadband noncoherent optical radiations usually must be performed by a highly trained specialist using sophisticated, complex, and expensive instruments. Presentation of the results of such measurement requires correct use of quantities and units with which many biological researchers are unfamiliar. The measurement process, physical quantities and units, measurement systems with instruments, and sources of error and uncertainties associated with optical radiation measurements are reviewed.

Development of Partially-Coherent Wavefront Propagation Simulation Methods for 3rd and 4th Generation Synchrotron Radiation Sources.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chubar O.; Berman, L; Chu, Y.S.

2012-04-04

Partially-coherent wavefront propagation calculations have proven to be feasible and very beneficial in the design of beamlines for 3rd and 4th generation Synchrotron Radiation (SR) sources. These types of calculations use the framework of classical electrodynamics for the description, on the same accuracy level, of the emission by relativistic electrons moving in magnetic fields of accelerators, and the propagation of the emitted radiation wavefronts through beamline optical elements. This enables accurate prediction of performance characteristics for beamlines exploiting high SR brightness and/or high spectral flux. Detailed analysis of radiation degree of coherence, offered by the partially-coherent wavefront propagation method, ismore » of paramount importance for modern storage-ring based SR sources, which, thanks to extremely small sub-nanometer-level electron beam emittances, produce substantial portions of coherent flux in X-ray spectral range. We describe the general approach to partially-coherent SR wavefront propagation simulations and present examples of such simulations performed using 'Synchrotron Radiation Workshop' (SRW) code for the parameters of hard X-ray undulator based beamlines at the National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory. These examples illustrate general characteristics of partially-coherent undulator radiation beams in low-emittance SR sources, and demonstrate advantages of applying high-accuracy physical-optics simulations to the optimization and performance prediction of X-ray optical beamlines in these new sources.« less

Clarity: An Open Source Manager for Laboratory Automation

PubMed Central

Delaney, Nigel F.; Echenique, José Rojas; Marx, Christopher J.

2013-01-01

Software to manage automated laboratories interfaces with hardware instruments, gives users a way to specify experimental protocols, and schedules activities to avoid hardware conflicts. In addition to these basics, modern laboratories need software that can run multiple different protocols in parallel and that can be easily extended to interface with a constantly growing diversity of techniques and instruments. We present Clarity: a laboratory automation manager that is hardware agnostic, portable, extensible and open source. Clarity provides critical features including remote monitoring, robust error reporting by phone or email, and full state recovery in the event of a system crash. We discuss the basic organization of Clarity; demonstrate an example of its implementation for the automated analysis of bacterial growth; and describe how the program can be extended to manage new hardware. Clarity is mature; well documented; actively developed; written in C# for the Common Language Infrastructure; and is free and open source software. These advantages set Clarity apart from currently available laboratory automation programs. PMID:23032169

Reverberation Chamber Uniformity Validation and Radiated Susceptibility Test Procedures for the NASA High Intensity Radiated Fields Laboratory

NASA Technical Reports Server (NTRS)

Koppen, Sandra V.; Nguyen, Truong X.; Mielnik, John J.

2010-01-01

The NASA Langley Research Center's High Intensity Radiated Fields Laboratory has developed a capability based on the RTCA/DO-160F Section 20 guidelines for radiated electromagnetic susceptibility testing in reverberation chambers. Phase 1 of the test procedure utilizes mode-tuned stirrer techniques and E-field probe measurements to validate chamber uniformity, determines chamber loading effects, and defines a radiated susceptibility test process. The test procedure is segmented into numbered operations that are largely software controlled. This document is intended as a laboratory test reference and includes diagrams of test setups, equipment lists, as well as test results and analysis. Phase 2 of development is discussed.

Galactic cosmic ray simulation at the NASA Space Radiation Laboratory

PubMed Central

Norbury, John W.; Schimmerling, Walter; Slaba, Tony C.; Azzam, Edouard I.; Badavi, Francis F.; Baiocco, Giorgio; Benton, Eric; Bindi, Veronica; Blakely, Eleanor A.; Blattnig, Steve R.; Boothman, David A.; Borak, Thomas B.; Britten, Richard A.; Curtis, Stan; Dingfelder, Michael; Durante, Marco; Dynan, William S.; Eisch, Amelia J.; Elgart, S. Robin; Goodhead, Dudley T.; Guida, Peter M.; Heilbronn, Lawrence H.; Hellweg, Christine E.; Huff, Janice L.; Kronenberg, Amy; La Tessa, Chiara; Lowenstein, Derek I.; Miller, Jack; Morita, Takashi; Narici, Livio; Nelson, Gregory A.; Norman, Ryan B.; Ottolenghi, Andrea; Patel, Zarana S.; Reitz, Guenther; Rusek, Adam; Schreurs, Ann-Sofie; Scott-Carnell, Lisa A.; Semones, Edward; Shay, Jerry W.; Shurshakov, Vyacheslav A.; Sihver, Lembit; Simonsen, Lisa C.; Story, Michael D.; Turker, Mitchell S.; Uchihori, Yukio; Williams, Jacqueline; Zeitlin, Cary J.

2017-01-01

Most accelerator-based space radiation experiments have been performed with single ion beams at fixed energies. However, the space radiation environment consists of a wide variety of ion species with a continuous range of energies. Due to recent developments in beam switching technology implemented at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), it is now possible to rapidly switch ion species and energies, allowing for the possibility to more realistically simulate the actual radiation environment found in space. The present paper discusses a variety of issues related to implementation of galactic cosmic ray (GCR) simulation at NSRL, especially for experiments in radiobiology. Advantages and disadvantages of different approaches to developing a GCR simulator are presented. In addition, issues common to both GCR simulation and single beam experiments are compared to issues unique to GCR simulation studies. A set of conclusions is presented as well as a discussion of the technical implementation of GCR simulation. PMID:26948012

Galactic cosmic ray simulation at the NASA Space Radiation Laboratory.

PubMed

Norbury, John W; Schimmerling, Walter; Slaba, Tony C; Azzam, Edouard I; Badavi, Francis F; Baiocco, Giorgio; Benton, Eric; Bindi, Veronica; Blakely, Eleanor A; Blattnig, Steve R; Boothman, David A; Borak, Thomas B; Britten, Richard A; Curtis, Stan; Dingfelder, Michael; Durante, Marco; Dynan, William S; Eisch, Amelia J; Robin Elgart, S; Goodhead, Dudley T; Guida, Peter M; Heilbronn, Lawrence H; Hellweg, Christine E; Huff, Janice L; Kronenberg, Amy; La Tessa, Chiara; Lowenstein, Derek I; Miller, Jack; Morita, Takashi; Narici, Livio; Nelson, Gregory A; Norman, Ryan B; Ottolenghi, Andrea; Patel, Zarana S; Reitz, Guenther; Rusek, Adam; Schreurs, Ann-Sofie; Scott-Carnell, Lisa A; Semones, Edward; Shay, Jerry W; Shurshakov, Vyacheslav A; Sihver, Lembit; Simonsen, Lisa C; Story, Michael D; Turker, Mitchell S; Uchihori, Yukio; Williams, Jacqueline; Zeitlin, Cary J

2016-02-01

Most accelerator-based space radiation experiments have been performed with single ion beams at fixed energies. However, the space radiation environment consists of a wide variety of ion species with a continuous range of energies. Due to recent developments in beam switching technology implemented at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), it is now possible to rapidly switch ion species and energies, allowing for the possibility to more realistically simulate the actual radiation environment found in space. The present paper discusses a variety of issues related to implementation of galactic cosmic ray (GCR) simulation at NSRL, especially for experiments in radiobiology. Advantages and disadvantages of different approaches to developing a GCR simulator are presented. In addition, issues common to both GCR simulation and single beam experiments are compared to issues unique to GCR simulation studies. A set of conclusions is presented as well as a discussion of the technical implementation of GCR simulation. Published by Elsevier Ltd.

Optical Imaging of Ionizing Radiation from Clinical Sources.

PubMed

Shaffer, Travis M; Drain, Charles Michael; Grimm, Jan

2016-11-01

Nuclear medicine uses ionizing radiation for both in vivo diagnosis and therapy. Ionizing radiation comes from a variety of sources, including x-rays, beam therapy, brachytherapy, and various injected radionuclides. Although PET and SPECT remain clinical mainstays, optical readouts of ionizing radiation offer numerous benefits and complement these standard techniques. Furthermore, for ionizing radiation sources that cannot be imaged using these standard techniques, optical imaging offers a unique imaging alternative. This article reviews optical imaging of both radionuclide- and beam-based ionizing radiation from high-energy photons and charged particles through mechanisms including radioluminescence, Cerenkov luminescence, and scintillation. Therapeutically, these visible photons have been combined with photodynamic therapeutic agents preclinically for increasing therapeutic response at depths difficult to reach with external light sources. Last, new microscopy methods that allow single-cell optical imaging of radionuclides are reviewed. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Sources and measurement of ultraviolet radiation.

PubMed

Diffey, Brian L

2002-09-01

Ultraviolet (UV) radiation is part of the electromagnetic spectrum. The biological effects of UV radiation vary enormously with wavelength and for this reason the UV spectrum is further subdivided into three regions: UVA, UVB, and UVC. Quantities of UV radiation are expressed using radiometric terminology. A particularly important term in clinical photobiology is the standard erythema dose (SED), which is a measure of the erythemal effectiveness of a UV exposure. UV radiation is produced either by heating a body to an incandescent temperature, as is the case with solar UV, or by passing an electric current through a gas, usually vaporized mercury. The latter process is the mechanism whereby UV radiation is produced artificially. Both the quality (spectrum) and quantity (intensity) of terrestrial UV radiation vary with factors including the elevation of the sun above the horizon and absorption and scattering by molecules in the atmosphere, notably ozone, and by clouds. For many experimental studies in photobiology it is simply not practicable to use natural sunlight and so artificial sources of UV radiation designed to simulate the UV component of sunlight are employed; these are based on either optically filtered xenon arc lamps or fluorescent lamps. The complete way to characterize an UV source is by spectroradiometry, although for most practical purposes a detector optically filtered to respond to a limited portion of the UV spectrum normally suffices.

SIMILARITY PROPERTIES AND SCALING LAWS OF RADIATION HYDRODYNAMIC FLOWS IN LABORATORY ASTROPHYSICS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Falize, E.; Bouquet, S.; Michaut, C., E-mail: emeric.falize@cea.fr

The spectacular recent development of modern high-energy density laboratory facilities which concentrate more and more energy in millimetric volumes allows the astrophysical community to reproduce and to explore, in millimeter-scale targets and during very short times, astrophysical phenomena where radiation and matter are strongly coupled. The astrophysical relevance of these experiments can be checked from the similarity properties and especially scaling law establishment, which constitutes the keystone of laboratory astrophysics. From the radiating optically thin regime to the so-called optically thick radiative pressure regime, we present in this paper, for the first time, a complete analysis of the main radiatingmore » regimes that we encountered in laboratory astrophysics with the same formalism based on Lie group theory. The use of the Lie group method appears to be a systematic method which allows us to construct easily and systematically the scaling laws of a given problem. This powerful tool permits us to unify the recent major advances on scaling laws and to identify new similarity concepts that we discuss in this paper, and suggests important applications for present and future laboratory astrophysics experiments. All these results enable us to demonstrate theoretically that astrophysical phenomena in such radiating regimes can be explored experimentally thanks to powerful facilities. Consequently, the results presented here are a fundamental tool for the high-energy density laboratory astrophysics community in order to quantify the astrophysics relevance and justify laser experiments. Moreover, relying on Lie group theory, this paper constitutes the starting point of any analysis of the self-similar dynamics of radiating fluids.« less

WORK SAFETY CONDITIONS WITH CLOSED RADIATION SOURCES (in Polish)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brosziewicz, R.

1963-01-01

A discussion is presented of principles of radiological protection observed in the Radiation Chemistry Dept. of the Nuclear Research Inst., during operation of large sources of ionizing radiation. It has been revealed that a properly designed servicing system of these sources ensures full protection of personnel even with not fully protected sources. (auth)

PREFACE: Acceleration and radiation generation in space and laboratory plasmas

NASA Astrophysics Data System (ADS)

Bingham, R.; Katsouleas, T.; Dawson, J. M.; Stenflo, L.

1994-01-01

and radiation generation in plasmas. The next section includes state-of-the-art papers on laboratory accelerators driven by lasers (Nakajima et al., Shukla, Johnson et al.), microwaves (Nishida et al., Bogomolov et al.) and by particle beams (Ogata et al.). Also in this section are theoretical papers presenting new work on synchrotron like oscillations in plasma waves (Fedele) and two types of laboratory radiation sources, FEL's (Marshall et al.) and ionization fronts (Lai et al.), and Frantzeskakis et al. described the Hamiltonian analysis of a slow-wave autonomous cyclotron buncher. Section 3 contains papers on astrophysical plasmas, with the general presentations of Colgate and Krishnan. Kazanas and Krishnan address active galactic nuclei (AGNs). Thielheim discusses general acceleration mech anisms in rotating magnetized systems. Asseo discussed Langmuir solitons in pulsars and Blackman et al. treat magnetic reconnection relativistically. Su et al. analyze the possibility of plasma wave excitation and particle acceleration by neu trinos from supernovae. Dogiel et al. on cosmic ray scattering by MHD fluctuations. The papers in Section 4 treat fusion plasmas (Dendy et al. and Lashmore-Davies et al.). Section 5, space plasmas, includes papers on acceleration processes in the magnetosphere (Anagnostopoulos and Marshall et al.) and the sun (Barletta et al.). It is evident from the Workshop and the papers collected here that this is indeed a rich field of investigations and that both the natural and laboratory plasma communities can benefit from the cross-fertilization of ideas between them. We wish to thank the authors and attendees for their contributions to the success of this workshop, Dr Philip Debenham and Dr David Sutter of the U.S. D.o.E. and Dr Charles Roberson of the U.S. O.N.R. for their financial support (Grants DE-FGO3-93ER40776 and N00014-93-1-0814), and the ECC Twinning Grant SC1*-CT92-0773. We appreciate the considerable local support from Mr Glegles and

VIEW OF BUILDING 126, LOOKING NORTH. BUILDING 126, THE SOURCE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF BUILDING 126, LOOKING NORTH. BUILDING 126, THE SOURCE CALIBRATION LABORATORY, WAS USED TO EXPOSE AND CALIBRATE RADIATION DETECTION DEVICES, INCLUDING THERMOLUMINESCENT DOSIMETERS, WORN BY EMPLOYEES TO DETECT RADIATION EXPOSURE - Rocky Flats Plant, Source Calibration Laboratory, Between Second & Third Streets & Central & Cedar Avenues, Golden, Jefferson County, CO

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aalseth, Craig E.; Bonicalzi, Ricco; Cantaloub, Michael G.

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. Wemore » conclude by presenting measurement targets and future opportunities.« less

Design of laboratory experiments to study photoionization fronts driven by thermal sources

DOE PAGES

Drake, R. P.; Hazak, G.; Keiter, P. A.; ...

2016-12-20

This study analyzes the requirements of a photoionization-front experiment that could be driven in the laboratory, using thermal sources to produce the necessary flux of ionizing photons. It reports several associated conclusions. Such experiments will need to employ the largest available facilities, capable of delivering many kJ to MJ of energy to an x-ray source. They will use this source to irradiate a volume of neutral gas, likely of N, on a scale of a few mm to a few cm, increasing with source energy. For a gas pressure of several to ten atmospheres at room temperature, and a sourcemore » temperature near 100 eV, one will be able to drive a photoionization front through a system of tens to hundreds of photon mean free paths. The front should make the familiar transition from the so-called R-Type to D-Type as the radiation flux diminishes with distance. The N is likely to reach the He-like state. Preheating from the energetic photons appears unlikely to become large enough to alter the essential dynamics of the front beyond some layer near the surface. For well-chosen experimental conditions, competing energy transport mechanisms are small.« less

DESIGN OF LABORATORY EXPERIMENTS TO STUDY PHOTOIONIZATION FRONTS DRIVEN BY THERMAL SOURCES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drake, R. P.; Keiter, P. A.; Davis, J. S.

2016-12-20

This paper analyzes the requirements of a photoionization-front experiment that could be driven in the laboratory, using thermal sources to produce the necessary flux of ionizing photons. It reports several associated conclusions. Such experiments will need to employ the largest available facilities, capable of delivering many kJ to MJ of energy to an X-ray source. They will use this source to irradiate a volume of neutral gas, likely of N, on a scale of a few mm to a few cm, increasing with source energy. For a gas pressure of several to ten atmospheres at room temperature, and a sourcemore » temperature near 100 eV, one will be able to drive a photoionization front through a system of tens to hundreds of photon mean free paths. The front should make the familiar transition from the so-called R-Type to D-Type as the radiation flux diminishes with distance. The N is likely to reach the He-like state. Preheating from the energetic photons appears unlikely to become large enough to alter the essential dynamics of the front beyond some layer near the surface. For well-chosen experimental conditions, competing energy transport mechanisms are small.« less

Synchrotron radiation laboratories at the Bonn electron accelerators. a status report

NASA Astrophysics Data System (ADS)

Hormes, J.

1987-07-01

At the Physikalisches Institut of the University in Bonn experiments with synchrotron radiation were carried out ever since 1962. At the moment (June 1986) all work takes place in the SR-laboratory at the 2.5 GeV synchrotron. A 3.5 GeV stretcher ring (ELSA) is under construction and will come into operation at the end of 1986. This accelerator will also run as a storage ring for synchrotron radiation experiments and a laboratory to be used at this machine is also under consideration. The SR experiments which are carried out in Bonn try to take advantage of the fact that we are still using a high energy synchrotron for our work. Besides basic research also applied work is done using synchrotron radiation even as a production tool for X-ray lithography.

Technical developments at the NASA Space Radiation Laboratory.

PubMed

Lowenstein, D I; Rusek, A

2007-06-01

The NASA Space Radiation Laboratory (NSRL) located at Brookhaven National Laboratory (BNL) is a center for space radiation research in both the life and physical sciences. BNL is a multidisciplinary research facility operated for the Office of Science of the US Department of Energy (DOE). The BNL scientific research portfolio supports a large and diverse science and technology program including research in nuclear and high-energy physics, material science, chemistry, biology, medial science, and nuclear safeguards and security. NSRL, in operation since July 2003, is an accelerator-based facility which provides particle beams for radiobiology and physics studies (Lowenstein in Phys Med 17(supplement 1):26-29 2001). The program focus is to measure the risks and to ameliorate the effects of radiation encountered in space, both in low earth orbit and extended missions beyond the earth. The particle beams are produced by the Booster synchrotron, an accelerator that makes up part of the injector sequence of the DOE nuclear physics program's Relativistic Heavy Ion Collider. Ion species from protons to gold are presently available, at energies ranging from <100 to >1,000 MeV/n. The NSRL facility has recently brought into operation the ability to rapidly switch species and beam energy to supply a varied spectrum onto a given specimen. A summary of past operation performance, plans for future operations and recent and planned hardware upgrades will be described.

Detailed observations of the source of terrestrial narrowband electromagnetic radiation

NASA Technical Reports Server (NTRS)

Kurth, W. S.

1982-01-01

Detailed observations are presented of a region near the terrestrial plasmapause where narrowband electromagnetic radiation (previously called escaping nonthermal continuum radiation) is being generated. These observations show a direct correspondence between the narrowband radio emissions and electron cyclotron harmonic waves near the upper hybrid resonance frequency. In addition, electromagnetic radiation propagating in the Z-mode is observed in the source region which provides an extremely accurate determination of the electron plasma frequency and, hence, density profile of the source region. The data strongly suggest that electrostatic waves and not Cerenkov radiation are the source of the banded radio emissions and define the coupling which must be described by any viable theory.

New developments and applications of intense pulsed radiation sources at Sandia National Laboratories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cook, D.

In the past thirty-six months, tremendous strides have been made in x-ray production using high-current z-pinches. Today, the x-ray energy (1.9 MJ) and power (200 TW) output of the Z accelerator (formerly PBFA-II) is the largest available in the laboratory. These z-pinch x-ray sources are being developed for research into the physics of high energy density plasmas of interest in weapon behavior and in inertial confinement fusion. Beyond the Z accelerator current of 20 MA, an extrapolation to the X-1 accelerator level of 60 MA may have the potential to drive high-yield ICF reactions at affordable cost if several challengingmore » technical problems can be overcome. New developments have also taken place at Sandia in the area of high current, mm-diameter electron beams for advanced hydrodynamic radiography. On SABRE, x-ray spot diameters were less than 2 mm with a dose of 100 R at 1 meter in a 40 ns pulse.« less

A compact radiation source for digital subtractive angiography

NASA Astrophysics Data System (ADS)

Wiedemann, H.; Baltay, M.; Carr, R.; Hernandez, M.; Lavender, W.

1994-08-01

Beam requirements for 33 keV radiation used in digital subtraction angiography have been established through extended experimentation first at Stanford and later at the National Synchrotron Light Source in Brookhaven. So far research and development of this medical procedure to image coronary blood vessels have been undertaken on large high energy electron storage rings. With progress in this diagnostic procedure, it is interesting to look for an optimum concept for providing a 33 keV radiation source which would fit into the environment of a hospital. A variety of competing effects and technologies to produce 33 keV radiation are available, but none of these processes provides the combination of sufficient photon flux and monochromaticity except for synchrotron radiation from an electron storage ring. The conceptual design of a compact storage ring optimized to fit into a hospital environment and producing sufficient 33 keV radiation for digital subtraction radiography will be discussed.

Perspectives of synchrotron radiation sources with superconductivity

NASA Astrophysics Data System (ADS)

Tanaka, Takashi

2007-10-01

The synchrotron radiation source is a magnetic device to generate a periodic magnetic field where a relativistic electron moves along a periodic trajectory and emits light called synchrotron radiation (SR), which has been used as a scientific probe for many years in various fields. Although permanent magnets (PMs) are usually used to generate the magnetic field in the SR source because of their cost-effectiveness and availability, a large number of SR sources with superconductors have been constructed for special uses, i.e., to obtain a strong magnetic field over 3 T, which cannot be achieved by using PMs alone. Most of these SR sources are composed of electromagnets with superconducting coils made of NbTi as in commercially available superconducting magnets. For stronger magnetic field, research on application of Nb3Sn is in progress. On the other hand, utilization of high Tc superconducting bulk magnets has been recently proposed and R&Ds toward realization are being carried out. This paper reviews the currents status of the SR sources with superconductivity and describes the future perspectives.

Creating a Driven, Collapsed Radiative Shock in the Laboratory

NASA Astrophysics Data System (ADS)

Reighard, Amy

2006-10-01

We report details of the first experimental campaign to create a driven, planar, radiatively collapsed in laboratory experiment. Radiation hydrodynamics experiments are challenging to realize in a laboratory setting, requiring high temperatures in a system of sufficient extent. The Omega laser at ˜10^15 W/cm^2 drives a thin slab of low-Z material at >100 km/s gas via laser ablation pressure. This slab initially shocks, then continues driving a shock through a cylindrical volume of Xe gas at 6 mg/cc. Simulations predict a collapsed layer in which the density reaches ˜45 times initial density. Side-on x-ray backlighting was the principal diagnostic. We have successfully imaged shocks with average velocities between 95-205 km/sec, with measured thicknesses of 45-150 μm in experiments lasting up to 20 ns and spanning up 2.5 mm in extent. Comparison of the shock position as a function of time from these experiments to 1D radiation hydrodynamic simulation results show some discrepancy, which will be explored. Optical depth before and behind the shock is important for meaningful comparison to these astrophysical systems. This shock is optically thin to emitted radiation in the unshocked region and optically thick to radiation in the shocked, dense region. We compare this system to collapsed shocks in astrophysical systems with similar optical depth profiles. An experiment using a Thomson scattering diagnostic across the shock front is also discussed. This research was sponsored by the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through DOE Research Grants DE-FG52-03NA00064, DE-FG53-2005-NA26014, and other grants and contracts.

Spontaneous Raman scattering as a high resolution XUV radiation source

NASA Technical Reports Server (NTRS)

Rothenberg, J. E.; Young, J. F.; Harris, S. E.

1983-01-01

A type of high resolution XUV radiation source is described which is based upon spontaneous anti-Stokes scattering of tunable incident laser radiation from atoms excited to metastable levels. The theory of the source is summarized and two sets of experiments using He (1s2s)(1)S atoms, produced in a cw hollow cathode and in a pulsed high power microwave discharge, are discussed. The radiation source is used to examine transitions originating from the 3p(6) shell of potassium. The observed features include four previously unreported absorption lines and several sharp interferences of closely spaced autoionizing lines. A source linewidth of about 1.9 cm(-1) at 185,000 cm(-1) is demonstrated.

Simulator training to minimize ionizing radiation exposure in the catheterization laboratory.

PubMed

Katz, Aric; Shtub, Avraham; Solomonica, Amir; Poliakov, Adva; Roguin, Ariel

2017-03-01

To learn about radiation and how to lower it. Patients and operators are routinely exposed to high doses of ionizing radiation during catheterization procedures. This increased exposure to ionizing radiation is partially due to a lack of awareness to the effects of ionizing radiation, and lack of knowledge on the distribution and behavior of scattered radiation. A simulator, which incorporates data on scattered ionizing radiation, was built based on multiple phantom measurements and used for teaching radiation safety. The validity of the simulator was confirmed in three catheterization laboratories and tested by 20 interventional cardiologists. All evaluators were tested by an objective knowledge examination before, immediately following, and 12 weeks after simulator-based learning and training. A subjective Likert questionnaire on satisfaction with simulation-based learning and training was also completed. The 20 evaluators learned and retained the knowledge that they gained from using the simulator: the average scores of the knowledge examination pre-simulator training was 54 ± 15% (mean ± standard deviation), and this score significantly increased after training to 94 ± 10% (p < 0.001). The evaluators also reported high levels of satisfaction following simulation-based learning and training according to the results of the subjective Likert questionnaire. Simulators can be used to train cardiology staff and fellows and to further educate experienced personnel on radiation safety. As a result of simulator training, the operator gains knowledge, which can then be applied in the catheterization laboratory in order to reduce radiation doses to the patient and to the operator, thereby improving the safety of the intervention.

Dose profile modeling of Idaho National Laboratory's active neutron interrogation laboratory.

PubMed

Chichester, D L; Seabury, E H; Zabriskie, J M; Wharton, J; Caffrey, A J

2009-06-01

A new laboratory has been commissioned at Idaho National Laboratory for performing active neutron interrogation research and development. The facility is designed to provide radiation shielding for deuterium-tritium (DT) fusion (14.1 MeV) neutron generators (2 x 10(8) n/s), deuterium-deuterium (DD) fusion (2.5 MeV) neutron generators (1 x 10(7) n/s), and (252)Cf spontaneous fission neutron sources (6.96 x 10(7) n/s, 30 microg). Shielding at the laboratory is comprised of modular concrete shield blocks 0.76 m thick with tongue-in-groove features to prevent radiation streaming, arranged into one small and one large test vault. The larger vault is designed to allow operation of the DT generator and has walls 3.8m tall, an entrance maze, and a fully integrated electrical interlock system; the smaller test vault is designed for (252)Cf and DD neutron sources and has walls 1.9 m tall and a simple entrance maze. Both analytical calculations and numerical simulations were used in the design process for the building to assess the performance of the shielding walls and to ensure external dose rates are within required facility limits. Dose rate contour plots have been generated for the facility to visualize the effectiveness of the shield walls and entrance mazes and to illustrate the spatial profile of the radiation dose field above the facility and the effects of skyshine around the vaults.

Wave field synthesis of moving virtual sound sources with complex radiation properties.

PubMed

Ahrens, Jens; Spors, Sascha

2011-11-01

An approach to the synthesis of moving virtual sound sources with complex radiation properties in wave field synthesis is presented. The approach exploits the fact that any stationary sound source of finite spatial extent radiates spherical waves at sufficient distance. The angular dependency of the radiation properties of the source under consideration is reflected by the amplitude and phase distribution on the spherical wave fronts. The sound field emitted by a uniformly moving monopole source is derived and the far-field radiation properties of the complex virtual source under consideration are incorporated in order to derive a closed-form expression for the loudspeaker driving signal. The results are illustrated via numerical simulations of the synthesis of the sound field of a sample moving complex virtual source.

Sustainably Sourced, Thermally Resistant, Radiation Hard Biopolymer

NASA Technical Reports Server (NTRS)

Pugel, Diane

2011-01-01

This material represents a breakthrough in the production, manufacturing, and application of thermal protection system (TPS) materials and radiation shielding, as this represents the first effort to develop a non-metallic, non-ceramic, biomaterial-based, sustainable TPS with the capability to also act as radiation shielding. Until now, the standing philosophy for radiation shielding involved carrying the shielding at liftoff or utilizing onboard water sources. This shielding material could be grown onboard and applied as needed prior to different radiation landscapes (commonly seen during missions involving gravitational assists). The material is a bioplastic material. Bioplastics are any combination of a biopolymer and a plasticizer. In this case, the biopolymer is a starch-based material and a commonly accessible plasticizer. Starch molecules are composed of two major polymers: amylase and amylopectin. The biopolymer phenolic compounds are common to the ablative thermal protection system family of materials. With similar constituents come similar chemical ablation processes, with the potential to have comparable, if not better, ablation characteristics. It can also be used as a flame-resistant barrier for commercial applications in buildings, homes, cars, and heater firewall material. The biopolymer is observed to undergo chemical transformations (oxidative and structural degradation) at radiation doses that are 1,000 times the maximum dose of an unmanned mission (10-25 Mrad), indicating that it would be a viable candidate for robust radiation shielding. As a comparison, the total integrated radiation dose for a three-year manned mission to Mars is 0.1 krad, far below the radiation limit at which starch molecules degrade. For electron radiation, the biopolymer starches show minimal deterioration when exposed to energies greater than 180 keV. This flame-resistant, thermal-insulating material is non-hazardous and may be sustainably sourced. It poses no hazardous

Beam tracking phase tomography with laboratory sources

NASA Astrophysics Data System (ADS)

Vittoria, F. A.; Endrizzi, M.; Kallon, G. K. N.; Hagen, C. K.; Diemoz, P. C.; Zamir, A.; Olivo, A.

2018-04-01

An X-ray phase-contrast laboratory system is presented, based on the beam-tracking method. Beam-tracking relies on creating micro-beamlets of radiation by placing a structured mask before the sample, and analysing them by using a detector with sufficient resolution. The system is used in tomographic configuration to measure the three dimensional distribution of the linear attenuation coefficient, difference from unity of the real part of the refractive index, and of the local scattering power of specimens. The complementarity of the three signals is investigated, together with their potential use for material discrimination.

Laboratory Training Manual on the Use of Isotopes and Radiation in Entomology.

ERIC Educational Resources Information Center

International Atomic Energy Agency, Vienna (Austria).

This publication should be useful for those who are interested in the theory and application of isotopes and radiation in agriculture and entomology. There are two main parts in the publication. Part I, entitled Basic Part, includes topics which an individual should know about radioisotopes and radiation. There are laboratory exercises included in…

Network Algorithms for Detection of Radiation Sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, Nageswara S; Brooks, Richard R; Wu, Qishi

In support of national defense, Domestic Nuclear Detection Office s (DNDO) Intelligent Radiation Sensor Systems (IRSS) program supported the development of networks of radiation counters for detecting, localizing and identifying low-level, hazardous radiation sources. Industry teams developed the first generation of such networks with tens of counters, and demonstrated several of their capabilities in indoor and outdoor characterization tests. Subsequently, these test measurements have been used in algorithm replays using various sub-networks of counters. Test measurements combined with algorithm outputs are used to extract Key Measurements and Benchmark (KMB) datasets. We present two selective analyses of these datasets: (a) amore » notional border monitoring scenario that highlights the benefits of a network of counters compared to individual detectors, and (b) new insights into the Sequential Probability Ratio Test (SPRT) detection method, which lead to its adaptations for improved detection. Using KMB datasets from an outdoor test, we construct a notional border monitoring scenario, wherein twelve 2 *2 NaI detectors are deployed on the periphery of 21*21meter square region. A Cs-137 (175 uCi) source is moved across this region, starting several meters from outside and finally moving away. The measurements from individual counters and the network were processed using replays of a particle filter algorithm developed under IRSS program. The algorithm outputs from KMB datasets clearly illustrate the benefits of combining measurements from all networked counters: the source was detected before it entered the region, during its trajectory inside, and until it moved several meters away. When individual counters are used for detection, the source was detected for much shorter durations, and sometimes was missed in the interior region. The application of SPRT for detecting radiation sources requires choosing the detection threshold, which in turn requires a source

Light-emitting diodes as a radiation source for plants

NASA Technical Reports Server (NTRS)

Bula, R. J.; Morrow, R. C.; Tibbitts, T. W.; Barta, D. J.; Ignatius, R. W.; Martin, T. S.

1991-01-01

Development of a more effective radiation source for use in plant-growing facilities would be of significant benefit for both research and commercial crop production applications. An array of light-emitting diodes (LEDs) that produce red radiation, supplemented with a photosynthetic photon flux (PPF) of 30 micromoles s-1 m-2 in the 400- to 500-nm spectral range from blue fluorescent lamps, was used effectively as a radiation source for growing plants. Growth of lettuce (Lactuca sativa L. Grand Rapids') plants maintained under the LED irradiation system at a total PPF of 325 micromoles s-1 m-2 for 21 days was equivalent to that reported in the literature for plants grown for the same time under cool-white fluorescent and incandescent radiation sources. Characteristics of the plants, such as leaf shape, color, and texture, were not different from those found with plants grown under cool-white fluorescent lamps. Estimations of the electrical energy conversion efficiency of a LED system for plant irradiation suggest that it may be as much as twice that published for fluorescent systems.

Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale.

PubMed

Kawamura, Yoshiyuki

2016-01-01

The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

Plasma wake field XUV radiation source

DOEpatents

Prono, Daniel S.; Jones, Michael E.

1997-01-01

A XUV radiation source uses an interaction of electron beam pulses with a gas to create a plasma radiator. A flowing gas system (10) defines a circulation loop (12) with a device (14), such as a high pressure pump or the like, for circulating the gas. A nozzle or jet (16) produces a sonic atmospheric pressure flow and increases the density of the gas for interacting with an electron beam. An electron beam is formed by a conventional radio frequency (rf) accelerator (26) and electron pulses are conventionally formed by a beam buncher (28). The rf energy is thus converted to electron beam energy, the beam energy is used to create and then thermalize an atmospheric density flowing gas to a fully ionized plasma by interaction of beam pulses with the plasma wake field, and the energetic plasma then loses energy by line radiation at XUV wavelengths Collection and focusing optics (18) are used to collect XUV radiation emitted as line radiation when the high energy density plasma loses energy that was transferred from the electron beam pulses to the plasma.

Effect of pulsed progressive fluoroscopy on reduction of radiation dose in the cardiac catheterization laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holmes, D.R. Jr.; Wondrow, M.A.; Gray, J.E.

1990-01-01

The increased application of therapeutic interventional cardiology procedures is associated with increased radiation exposure to physicians, patients and technical personnel. New advances in imaging techniques have the potential for reducing radiation exposure. A progressive scanning video system with a standard vascular phantom has been shown to decrease entrance radiation exposure. The effect of this system on reducing actual radiation exposure to physicians and technicians was assessed from 1984 through 1987. During this time, progressive fluoroscopy was added sequentially to all four adult catheterization laboratories; no changes in shielding procedures were made. During this time, the case load per physician increasedmore » by 63% and the number of percutaneous transluminal coronary angioplasty procedures (a high radiation procedure) increased by 244%. Despite these increases in both case load and higher radiation procedures, the average radiation exposure per physician declined by 37%. During the same time, the radiation exposure for technicians decreased by 35%. Pulsed progressive fluoroscopy is effective for reducing radiation exposure to catheterization laboratory physicians and technical staff.« less

Search for Artificial Stellar Sources of Infrared Radiation.

PubMed

Dyson, F J

1960-06-03

If extraterrestrial intelligent beings exist and have reached a high level of technical development, one by-product of their energy metabolism is likely to be the large-scale conversion of starlight into far-infrared radiation. It is proposed that a search for sources of infrared radiation should accompany the recently initiated search for interstellar radio communications.

78 FR 21567 - Installation of Radiation Alarms for Rooms Housing Neutron Sources

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-11

... [Docket No. PRM-73-15; NRC-2011-0251] Installation of Radiation Alarms for Rooms Housing Neutron Sources... amend its regulations to require the installation of radiation alarms for rooms housing neutron sources... alarms for rooms housing neutron sources. The petitioner stated that the use of alarms can be effective...

Solar radiation data sources, applications, and network design

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

A prerequisite to considering solar energy projects is to determine the requirements for information about solar radiation to apply to possible projects. This report offers techniques to help the reader specify requirements in terms of solar radiation data and information currently available, describes the past and present programs to record and present information to be used for most requirements, presents courses of action to help the user meet his needs for information, lists sources of solar radiation data and presents the problems, costs, benefits and responsibilities of programs to acquire additional solar radiation data. Extensive background information is provided aboutmore » solar radiation data and its use. Specialized information about recording, collecting, processing, storing and disseminating solar radiation data is given. Several Appendices are included which provide reference material for special situations.« less

Evolution of organic molecules under Mars-like UV radiation conditions in space and laboratory

NASA Astrophysics Data System (ADS)

Rouquette, L.; Stalport, F.; Cottin, H.; Coll, P.; Szopa, C.; Saiagh, K.; Poch, O.; Khalaf, D.; Chaput, D.; Grira, K.; Dequaire, T.

2017-09-01

The detection and identification of organic molecules at Mars are of prime importance, as some of these molecules are life precursors and components. While in situ planetary missions are searching for them, it is essential to understand how organic molecules evolve and are preserved at the surface of Mars. Indeed the harsh conditions of the environment of Mars such as ultraviolet (UV) radiation or oxidative processes could explain the low abundance and diversity of organic molecules detected by now [1]. In order to get a better understanding of the evolution of organic matter at the surface of Mars, we exposed organic molecules under a Mars-like UV radiation environment. Similar organic samples were exposed to the Sun radiation, outside the International Space Station (ISS), and under a UV lamp (martian pressure and temperature conditions) in the laboratory. In both experiments, organic molecules tend to photodegrade under Mars-like UV radiation. Minerals, depending on their nature, can protect or accelerate the degradation of organic molecules. For some molecules, new products, possibly photoresistant, seem to be produced. Finally, experimenting in space allow us to get close to in situ conditions and to validate our laboratory experiment while the laboratory experiment is essential to study the evolution of a large amount and diversity of organic molecules.

NIF laboratory astrophysics simulations investigating the effects of a radiative shock on hydrodynamic instabilities

NASA Astrophysics Data System (ADS)

Angulo, A. A.; Kuranz, C. C.; Drake, R. P.; Huntington, C. M.; Park, H.-S.; Remington, B. A.; Kalantar, D.; MacLaren, S.; Raman, K.; Miles, A.; Trantham, Matthew; Kline, J. L.; Flippo, K.; Doss, F. W.; Shvarts, D.

2016-10-01

This poster will describe simulations based on results from ongoing laboratory astrophysics experiments at the National Ignition Facility (NIF) relevant to the effects of radiative shock on hydrodynamically unstable surfaces. The experiments performed on NIF uniquely provide the necessary conditions required to emulate radiative shock that occurs in astrophysical systems. The core-collapse explosions of red supergiant stars is such an example wherein the interaction between the supernova ejecta and the circumstellar medium creates a region susceptible to Rayleigh-Taylor (R-T) instabilities. Radiative and nonradiative experiments were performed to show that R-T growth should be reduced by the effects of the radiative shocks that occur during this core-collapse. Simulations were performed using the radiation hydrodynamics code Hyades using the experimental conditions to find the mean interface acceleration of the instability and then further analyzed in the buoyancy drag model to observe how the material expansion contributes to the mix-layer growth. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas under Grant Number DE-FG52-09NA29548.

Laboratory Kinetic Studies of OH and CO2 Relevant to Upper Atmospheric Radiation Balance

NASA Technical Reports Server (NTRS)

Nelson, David D.; Villalta, Peter; Zahniser, Mark S.; Kolb, Charles E.

1997-01-01

The purpose of this project was to quantify the rates of two processes which are crucial to our understanding of radiative energy balance in the upper atmosphere. The first process is radiative emission from vibrationally hot OH radicals following the H + O3 reaction in the upper mesosphere. The importance of this process depends strongly on the OH radiative emission coefficients. Our goal was to measure the OH permanent dipole moment in excited vibrational states and to use these measurements to construct an improved OH dipole moment function and improved radiative emission coefficients. Significant progress was made on these experiments including the construction of a supersonic jet source for vibrationally excited OH radicals. Unfortunately, our efforts to transport the OH radicals into a second lower pressure vacuum chamber were not successful, and we were unable to make improved dipole moment measurements for OH. The second key kinetic process which we attempted to quantify during this project is the rate of relaxation of bend-excited CO2 by oxygen atoms. Since excitation of the bending vibrational mode of CO2 is the major cooling mechanism in the upper mesosphere/lower thermosphere, the cooling rate of this region depends crucially on the rate of energy transfer out of this state. It is believed that the most efficient transfer mechanism is via atomic oxygen but the rate for this process has not been directly measured in the laboratory at appropriate temperatures and even the room temperature rate remains controversial. We attempted to directly measure the relaxation rate Of CO2 (010) by oxygen atoms using the discharge flow technique. This experiment was set up at Aerodyne Research. Again, significant progress was achieved in this experiment. A hot CO2 source was set up, bend excited CO2 was detected and the rate of relaxation of bend excited CO2 by He atoms was measured. Unfortunately, the project ran out of time before the oxygen atom kinetic studies could

Nonuniformity correction of imaging systems with a spatially nonhomogeneous radiation source.

PubMed

Gutschwager, Berndt; Hollandt, Jörg

2015-12-20

We present a novel method of nonuniformity correction of imaging systems in a wide optical spectral range by applying a radiation source with an unknown and spatially nonhomogeneous radiance or radiance temperature distribution. The benefit of this method is that it can be applied with radiation sources of arbitrary spatial radiance or radiance temperature distribution and only requires the sufficient temporal stability of this distribution during the measurement process. The method is based on the recording of several (at least three) images of a radiation source and a purposeful row- and line-shift of these sequent images in relation to the first primary image. The mathematical procedure is explained in detail. Its numerical verification with a source of a predefined nonhomogenous radiance distribution and a thermal imager of a predefined nonuniform focal plane array responsivity is presented.

Radiological protection, safety and security issues in the industrial and medical applications of radiation sources

NASA Astrophysics Data System (ADS)

Vaz, Pedro

2015-11-01

The use of radiation sources, namely radioactive sealed or unsealed sources and particle accelerators and beams is ubiquitous in the industrial and medical applications of ionizing radiation. Besides radiological protection of the workers, members of the public and patients in routine situations, the use of radiation sources involves several aspects associated to the mitigation of radiological or nuclear accidents and associated emergency situations. On the other hand, during the last decade security issues became burning issues due to the potential malevolent uses of radioactive sources for the perpetration of terrorist acts using RDD (Radiological Dispersal Devices), RED (Radiation Exposure Devices) or IND (Improvised Nuclear Devices). A stringent set of international legally and non-legally binding instruments, regulations, conventions and treaties regulate nowadays the use of radioactive sources. In this paper, a review of the radiological protection issues associated to the use of radiation sources in the industrial and medical applications of ionizing radiation is performed. The associated radiation safety issues and the prevention and mitigation of incidents and accidents are discussed. A comprehensive discussion of the security issues associated to the global use of radiation sources for the aforementioned applications and the inherent radiation detection requirements will be presented. Scientific, technical, legal, ethical, socio-economic issues are put forward and discussed.

Laboratory investigation of fire radiative energy and smoke aerosol emissions

Treesearch

Charles Ichoku; J. Vanderlei Martins; Yoram J. Kaufman; Martin J. Wooster; Patrick H. Freeborn; Wei Min Hao; Stephen Baker; Cecily A. Ryan; Bryce L. Nordgren

2008-01-01

Fuel biomass samples from southern Africa and the United States were burned in a laboratory combustion chamber while measuring the biomass consumption rate, the fire radiative energy (FRE) release rate (Rfre), and the smoke concentrations of carbon monoxide (CO), carbon dioxide (CO2), and particulate matter (PM). The PM mass emission rate (RPM) was quantified from...

UV Radiation: a new first year physics/life sciences laboratory experiment

NASA Astrophysics Data System (ADS)

Petelina, S. V.; Siddaway, J. M.

2010-12-01

Unfortunately, Australia leads the world in the number of skin cancer cases per capita. Three major factors that contribute to this are: 1) the level of damaging ultraviolet (UV) radiation in Australia is higher than in many other countries. This is caused, among other factors, by the stratospheric ozone depletion and Antarctic ozone hole; 2) many people in Australia are of Irish-Scottish origin and their skin can not repair the damage caused by the UV radiation as effectively as the skin of people of other origins; 3) Australia is one of the world’s leaders in the outdoor activities where people tend to spend more time outside. As our experience has shown, most Australian University students, high school students, and even high school teachers were largely unaware of the UV damage details and effective safety measures. Therefore, a need for new ways to educate people became apparent. The general aim of this new 1st year laboratory experiment, developed and first offered at La Trobe University (Melbourne, Australia) in 2009, is to investigate how UV-B radiation levels change under various solar illumination conditions and how effective different types of protection are. After pre-lab readings on physical concepts and biological effects of UV radiation, and after solving all pre-lab problems, the students go outside and measure the actual change in UV-B and UV-A radiation levels under various conditions. Some of these conditions are: direct sun, shade from a building, shade under the roof, reflection from various surfaces, direct sun through cheap and expensive sunglasses and eyeglasses, direct sun through various types of cloth and hair. The equipment used is the UV-Probe manufactured by sglux SolGel Technologies GmbH. The students’ feedback on this new laboratory experiment was very positive. It was ranked top among all physics experiments offered as part of that subject (Physics for Life Sciences) in 2009 and top among all physics experiments presented for

On the use of a laser ablation as a laboratory seismic source

NASA Astrophysics Data System (ADS)

Shen, Chengyi; Brito, Daniel; Diaz, Julien; Zhang, Deyuan; Poydenot, Valier; Bordes, Clarisse; Garambois, Stéphane

2017-04-01

Mimic near-surface seismic imaging conducted in well-controlled laboratory conditions is potentially a powerful tool to study large scale wave propagations in geological media by means of upscaling. Laboratory measurements are indeed particularly suited for tests of theoretical modellings and comparisons with numerical approaches. We have developed an automated Laser Doppler Vibrometer (LDV) platform, which is able to detect and register broadband nano-scale displacements on the surface of various materials. This laboratory equipment has already been validated in experiments where piezoelectric transducers were used as seismic sources. We are currently exploring a new seismic source in our experiments, a laser ablation, in order to compensate some drawbacks encountered with piezoelectric sources. The laser ablation source is considered to be an interesting ultrasound wave generator since the 1960s. It was believed to have numerous potential applications such as the Non-Destructive Testing (NDT) and the measurements of velocities and attenuations in solid samples. We aim at adapting and developing this technique into geophysical experimental investigations in order to produce and explore complete micro-seismic data sets in the laboratory. We will first present the laser characteristics including its mechanism, stability, reproducibility, and will evaluate in particular the directivity patterns of such a seismic source. We have started by applying the laser ablation source on the surfaces of multi-scale homogeneous aluminum samples and are now testing it on heterogeneous and fractured limestone cores. Some other results of data processing will also be shown, especially the 2D-slice V P and V S tomographic images obtained in limestone samples. Apart from the experimental records, numerical simulations will be carried out for both the laser source modelling and the wave propagation in different media. First attempts will be done to compare quantitatively the

Space Radiation Research at NASA

NASA Technical Reports Server (NTRS)

Norbury, John

2016-01-01

The harmful effects of space radiation on astronauts is one of the most important limiting factors for human exploration of space beyond low Earth orbit, including a journey to Mars. This talk will present an overview of space radiation issues that arise throughout the solar system and will describe research efforts at NASA aimed at studying space radiation effects on astronauts, including the experimental program at the NASA Space Radiation Laboratory at Brookhaven National Laboratory. Recent work on galactic cosmic ray simulation at ground based accelerators will also be presented. The three major sources of space radiation, namely geomagnetically trapped particles, solar particle events and galactic cosmic rays will be discussed as well as recent discoveries of the harmful effects of space radiation on the human body. Some suggestions will also be given for developing a space radiation program in the Republic of Korea.

DOSIS & DOSIS 3D: radiation measurements with the DOSTEL instruments onboard the Columbus Laboratory of the ISS in the years 2009-2016

NASA Astrophysics Data System (ADS)

Berger, Thomas; Burmeister, Sönke; Matthiä, Daniel; Przybyla, Bartos; Reitz, Günther; Bilski, Pawel; Hajek, Michael; Sihver, Lembit; Szabo, Julianna; Ambrozova, Iva; Vanhavere, Filip; Gaza, Ramona; Semones, Edward; Yukihara, Eduardo G.; Benton, Eric R.; Uchihori, Yukio; Kodaira, Satoshi; Kitamura, Hisashi; Boehme, Matthias

2017-03-01

The natural radiation environment in Low Earth Orbit (LEO) differs significantly in composition and energy from that found on Earth. The space radiation field consists of high energetic protons and heavier ions from Galactic Cosmic Radiation (GCR), as well as of protons and electrons trapped in the Earth's radiation belts (Van Allen belts). Protons and some heavier particles ejected in occasional Solar Particle Events (SPEs) might in addition contribute to the radiation exposure in LEO. All sources of radiation are modulated by the solar cycle. During solar maximum conditions SPEs occur more frequently with higher particle intensities. Since the radiation exposure in LEO exceeds exposure limits for radiation workers on Earth, the radiation exposure in space has been recognized as a main health concern for humans in space missions from the beginning of the space age on. Monitoring of the radiation environment is therefore an inevitable task in human spaceflight. Since mission profiles are always different and each spacecraft provides different shielding distributions, modifying the radiation environment measurements needs to be done for each mission. The experiments "Dose Distribution within the ISS (DOSIS)" (2009-2011) and "Dose Distribution within the ISS 3D (DOSIS 3D)" (2012-onwards) onboard the Columbus Laboratory of the International Space Station (ISS) use a detector suite consisting of two silicon detector telescopes (DOSimetry TELescope = DOSTEL) and passive radiation detector packages (PDP) and are designed for the determination of the temporal and spatial variation of the radiation environment. With the DOSTEL instruments' changes of the radiation composition and the related exposure levels in dependence of the solar cycle, the altitude of the ISS and the influence of attitude changes of the ISS during Space Shuttle dockings inside the Columbus Laboratory have been monitored. The absorbed doses measured at the end of May 2016 reached up to 286 �

Infrared Measurements of AFGL (Air Force Geophysics Laboratory) Sources.

DTIC Science & Technology

1983-06-07

of sources brighter than magnitude [ X ] is plotted against [ X ] in figures 3 and 4. The LL source counts are plotted as dots in these two figu re s. From...radiation is from, a cir- cumstellar dust shell. The characteristic temperature of these shells 21 *~** * * ** X ...scale height. We find: N([4)) = 3 x 10 -7 pc -3 and N(L1Q]) = 9 x 10 .8 pc 3 . Kirton and Fitzgerald (1974) found the density of late M stars (M5-9) to

Terrestrial black holes as sources of super-high energy radiation

NASA Astrophysics Data System (ADS)

Trofimenko, A. P.; Gurin, V. S.

1993-04-01

The study proposes small black holes which can be located in the earth's interior as sources of superhigh energy radiation; their origin is not constrained to the big bang. The intensity and spectrum of massless and massive particle radiation due to the Hawking effect for black holes with masses of 10 exp 8 to 10 exp 16 are estimated. The possibility of their detection according to a number of features (high particle energies, thermal energetic spectrum, transientness or an explicit trend to intensity and energy increase, and some expressed direction of emission associated with source localization) is explored. The rates of the radiation of massless particles with spin-1/2 and with spin-1 are illustrated in graphic form.

Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover.

PubMed

Hassler, Donald M; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L; Brinza, David E; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P

2014-01-24

The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

1994 activity report: Stanford Synchrotron Radiation Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cantwell, K.; Dunn, L.

1994-01-01

The SSRL facility delivered 89% of the scheduled user beam to 25 experimental stations during 6.5 months of user running. Users from private industry were involved in 31% of these experiments. The SPEAR accelerator ran very well with no major component failures and an unscheduled down time of only 2.9%. In addition to this increased reliability, there was a significant improvement in the stability of the beam. The enhancements to the SPEAR orbit as part of a concerted three-year program were particularly noticeable to users. The standard deviation of beam movement (both planes) in the last part of the runmore » was 80 microns, major progress toward the ultimate goal of 50-micron stability. This was a significant improvement from the previous year when the movement was 400 microns in the horizontal and 200 microns in the vertical. A new accelerator Personal Protection System (PPS), built with full redundancy and providing protection from both radiation exposure and electrical hazards, was installed in 1994. It is not possible to describe in this summary all of the scientific experimentation which was performed during the run. However, the flavor of current research projects and the many significant accomplishments can be realized by the following highlights: A multinational collaboration performed several experiments involving x-ray scattering from nuclear resonances; Studies related to nuclear waste remediation by groups from Los Alamos National Laboratory and Pacific Northwest Laboratories continued in 1994; Diffraction data sets for a number of important protein crystals were obtained; During the past two years a collaboration consisting of groups from Hewlett Packard, Intel, Fisons Instruments and SSRL has been exploring the utility of synchrotron radiation for total reflection x-ray fluorescence (TRXRF); and High-resolution angle-resolved photoemission experiments have continued to generate exciting new results from highly correlated and magnetic materials.« less

Determination of Jet Noise Radiation Source Locations using a Dual Sideline Cross-Correlation/Spectrum Technique

NASA Technical Reports Server (NTRS)

Allen, C. S.; Jaeger, S. M.

1999-01-01

The goal of our efforts is to extrapolate nearfield jet noise measurements to the geometric far field where the jet noise sources appear to radiate from a single point. To accomplish this, information about the location of noise sources in the jet plume, the radiation patterns of the noise sources and the sound pressure level distribution of the radiated field must be obtained. Since source locations and radiation patterns can not be found with simple single microphone measurements, a more complicated method must be used.

Multiple Detector Optimization for Hidden Radiation Source Detection

DTIC Science & Technology

2015-03-26

important in achieving operationally useful methods for optimizing detector emplacement, the 2-D attenuation model approach promises to speed up the...process of hidden source detection significantly. The model focused on detection of the full energy peak of a radiation source. Methods to optimize... radioisotope identification is possible without using a computationally intensive stochastic model such as the Monte Carlo n-Particle (MCNP) code

An Experimental Investigation of the Role of Radiation in Laboratory Bench-Top Experiments in Thermal Physics

ERIC Educational Resources Information Center

Twomey, Patrick; O'Sullivan, Colm; O'Riordan, John

2009-01-01

A simple undergraduate experiment designed to study cooling purely by radiation and cooling by a combination of convection and radiation is described. Results indicate that the contribution from radiative cooling in normal laboratory experiments is more significant than students often realize, even in the case of forced cooling. (Contains 1…

Radiation Resistance of Soil Azotobacter

PubMed Central

Vela, Gerard R.; Wyss, Orville

1965-01-01

Vela, Gerard R. (School of Aerospace Medicine, Brooks Air Force Base, Tex.), and Orville Wyss. Radiation resistance of soil Azotobacter. J. Bacteriol. 89:1280–1285. 1965.—Quantitative recovery of Azotobacter from soils subjected to γ-radiation from a cobalt-60 source showed the soil populations to be much more highly resistant than isolates from such cultures grown on laboratory media. Even in the encysted state, the laboratory populations were reduced 10,000-fold by exposure to 200 kr, whereas the soil populations were not measurably reduced by that dose. PMID:14292998

Fan Noise Prediction System Development: Source/Radiation Field Coupling and Workstation Conversion for the Acoustic Radiation Code

NASA Technical Reports Server (NTRS)

Meyer, H. D.

1993-01-01

The Acoustic Radiation Code (ARC) is a finite element program used on the IBM mainframe to predict far-field acoustic radiation from a turbofan engine inlet. In this report, requirements for developers of internal aerodynamic codes regarding use of their program output an input for the ARC are discussed. More specifically, the particular input needed from the Bolt, Beranek and Newman/Pratt and Whitney (turbofan source noise generation) Code (BBN/PWC) is described. In a separate analysis, a method of coupling the source and radiation models, that recognizes waves crossing the interface in both directions, has been derived. A preliminary version of the coupled code has been developed and used for initial evaluation of coupling issues. Results thus far have shown that reflection from the inlet is sufficient to indicate that full coupling of the source and radiation fields is needed for accurate noise predictions ' Also, for this contract, the ARC has been modified for use on the Sun and Silicon Graphics Iris UNIX workstations. Changes and additions involved in this effort are described in an appendix.

The Radiation, Interplanetary Shocks, and Coronal Sources (RISCS) Toolset

NASA Technical Reports Server (NTRS)

Zank, G. P.; Spann, James F.

2014-01-01

The goal of this project is to serve the needs of space system designers and operators by developing an interplanetary radiation environment model within 10 AU:Radiation, Interplanetary Shocks, and Coronal Sources (RISCS) toolset: (1) The RISCS toolset will provide specific reference environments for space system designers and nowcasting and forecasting capabilities for space system operators; (2) We envision the RISCS toolset providing the spatial and temporal radiation environment external to the Earth's (and other planets') magnetosphere, as well as possessing the modularity to integrate separate applications (apps) that can map to specific magnetosphere locations and/or perform the subsequent radiation transport and dosimetry for a specific target.

Radiative Transfer in a Translucent Cloud Illuminated by an Extended Background Source

NASA Astrophysics Data System (ADS)

Biganzoli, Davide; Potenza, Marco A. C.; Robberto, Massimo

2017-05-01

We discuss the radiative transfer theory for translucent clouds illuminated by an extended background source. First, we derive a rigorous solution based on the assumption that multiple scatterings produce an isotropic flux. Then we derive a more manageable analytic approximation showing that it nicely matches the results of the rigorous approach. To validate our model, we compare our predictions with accurate laboratory measurements for various types of well-characterized grains, including purely dielectric and strongly absorbing materials representative of astronomical icy and metallic grains, respectively, finding excellent agreement without the need to add free parameters. We use our model to explore the behavior of an astrophysical cloud illuminated by a diffuse source with dust grains having parameters typical of the classic ISM grains of Draine & Lee and protoplanetary disks, with an application to the dark silhouette disk 114-426 in Orion Nebula. We find that the scattering term modifies the transmitted radiation, both in terms of intensity (extinction) and shape (reddening) of the spectral distribution. In particular, for small optical thickness, our results show that scattering makes reddening almost negligible at visible wavelengths. Once the optical thickness increases enough and the probability of scattering events becomes close to or larger than 1, reddening becomes present but is appreciably modified with respect to the standard expression for line-of-sight absorption. Moreover, variations of the grain refractive index, in particular the amount of absorption, also play an important role in changing the shape of the spectral transmission curve, with dielectric grains showing the minimum amount of reddening.

Radiation chemistry in the Jovian stratosphere - Laboratory simulations

NASA Technical Reports Server (NTRS)

Mcdonald, Gene D.; Thompson, W. R.; Sagan, Carl

1992-01-01

The results of the present low-pressure/continuous-flow laboratory simulations of H2/He/CH4/NH3 atmospheres' plasma-induced chemistry indicate radiation yields of both hydrocarbon and N2-containing organic compounds which increase with decreasing pressure. On the basis of these findings, upper limits of 1 million-1 billion molecules/sq cm/sec are established for production rates of major auroral-chemistry species in the Jovian stratosphere. It is noted that auroral processes may account for 10-100 percent of the total abundances of most of the observed polar-region organic species.

Distributed Sensing for Quickest Change Detection of Point Radiation Sources

DTIC Science & Technology

2017-02-01

point occurs simultaneously at all sensor nodes, thus neglecting signal propagation delays. For nuclear radiation , the observation period, which is on... nuclear radiation using a sensor network,” in Homeland Security (HST), 2012 IEEE Conference on Technologies for. IEEE, 2012, pp. 648–653. [8] G. Lorden...Distributed Sensing for Quickest Change Detection of Point Radiation Sources Gene T. Whipps⋆† Emre Ertin† Randolph L. Moses† †The Ohio State

Intrinsic Radiation Source Generation with the ISC Package: Data Comparisons and Benchmarking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Solomon, Clell J. Jr.

The characterization of radioactive emissions from unstable isotopes (intrinsic radiation) is necessary for shielding and radiological-dose calculations from radioactive materials. While most radiation transport codes, e.g., MCNP [X-5 Monte Carlo Team, 2003], provide the capability to input user prescribed source definitions, such as radioactive emissions, they do not provide the capability to calculate the correct radioactive-source definition given the material compositions. Special modifications to MCNP have been developed in the past to allow the user to specify an intrinsic source, but these modification have not been implemented into the primary source base [Estes et al., 1988]. To facilitate the descriptionmore » of the intrinsic radiation source from a material with a specific composition, the Intrinsic Source Constructor library (LIBISC) and MCNP Intrinsic Source Constructor (MISC) utility have been written. The combination of LIBISC and MISC will be herein referred to as the ISC package. LIBISC is a statically linkable C++ library that provides the necessary functionality to construct the intrinsic-radiation source generated by a material. Furthermore, LIBISC provides the ability use different particle-emission databases, radioactive-decay databases, and natural-abundance databases allowing the user flexibility in the specification of the source, if one database is preferred over others. LIBISC also provides functionality for aging materials and producing a thick-target bremsstrahlung photon source approximation from the electron emissions. The MISC utility links to LIBISC and facilitates the description of intrinsic-radiation sources into a format directly usable with the MCNP transport code. Through a series of input keywords and arguments the MISC user can specify the material, age the material if desired, and produce a source description of the radioactive emissions from the material in an MCNP readable format. Further details of using the MISC

Measurement of an image jitter of an extended incoherent radiation source

NASA Astrophysics Data System (ADS)

Lukin, V. P.; Nosov, V. V.

2017-06-01

A scheme of an image jitter measuring device, which uses an extended incoherent source as a radiation source, is presented. The efficiency of the measuring device is analysed analytically and numerically in order to justify the operation of the adaptive optical system that does not require special creation or formation of a reference source. The features of the formed image of incoherent radiation are considered, in particular from the point of view of its possible application for measuring the phase fluctuations of optical waves propagating in a turbulent atmosphere (the adaptive system monitors the image of a self-luminous object illuminated by extraneous sources). The possibility of utilising a Shack-Hartmann wavefront sensor in adaptive systems using the image of an arbitrary object (or its fragment) as a reference source is shown.

University Physics Students' Ideas of Thermal Radiation Expressed in Open Laboratory Activities Using Infrared Cameras

ERIC Educational Resources Information Center

Haglund, Jesper; Melander, Emil; Weiszflog, Matthias; Andersson, Staffan

2017-01-01

Background: University physics students were engaged in open-ended thermodynamics laboratory activities with a focus on understanding a chosen phenomenon or the principle of laboratory apparatus, such as thermal radiation and a heat pump. Students had access to handheld infrared (IR) cameras for their investigations. Purpose: The purpose of the…

Increasing EUV source efficiency via recycling of radiation power

NASA Astrophysics Data System (ADS)

Hassanein, Ahmed; Sizyuk, Valeryi; Sizyuk, Tatyana; Johnson, Kenneth C.

2018-03-01

EUV source power is critical for advanced lithography, for achieving economical throughput performance and also for minimizing stochastic patterning effects. Power conversion efficiency can be increased by recycling plasma-scattered laser radiation and other out-of-band radiation back to the plasma via retroreflective optics. Radiation both within and outside of the collector light path can potentially be recycled. For recycling within the collector path, the system uses a diffractive collection mirror that concomitantly filters all laser and out-of-band radiation out of the EUV output. In this paper we review the optical design concept for power recycling and present preliminary plasma-physics simulation results showing a potential gain of 60% in EUV conversion efficiency.

The electromagnetic radiation from simple sources in the presence of a homogeneous dielectric sphere

NASA Technical Reports Server (NTRS)

Mason, V. B.

1973-01-01

In this research, the effect of a homogeneous dielectric sphere on the electromagnetic radiation from simple sources is treated as a boundary value problem, and the solution is obtained by the technique of dyadic Green's functions. Exact representations of the electric fields in the various regions due to a source located inside, outside, or on the surface of a dielectric sphere are formulated. Particular attention is given to the effect of sphere size, source location, dielectric constant, and dielectric loss on the radiation patterns and directivity of small spheres (less than 5 wavelengths in diameter) using the Huygens' source excitation. The computed results are found to closely agree with those measured for waveguide-excited plexiglas spheres. Radiation patterns for an extended Huygens' source and for curved electric dipoles located on the sphere's surface are also presented. The resonance phenomenon associated with the dielectric sphere is studied in terms of the modal representation of the radiated fields. It is found that when the sphere is excited at certain frequencies, much of the energy is radiated into the sidelobes. The addition of a moderate amount of dielectric loss, however, quickly attenuates this resonance effect. A computer program which may be used to calculate the directivity and radiation pattern of a Huygens' source located inside or on the surface of a lossy dielectric sphere is listed.

Aircraft Radiation Shield Experiments--Preflight Laboratory Testing

NASA Technical Reports Server (NTRS)

Singleterry, Robert C., Jr.; Shinn, Judy L.; Wilson, John W.; Maiden, Donald L.; Thibeault, Sheila A.; Badavi, Francis F.; Conroy, Thomas; Braby, Leslie

1999-01-01

In the past, measurements onboard a research Boeing 57F (RB57-F) aircraft have demonstrated that the neutron environment within the aircraft structure is greater than that in the local external environment. Recent studies onboard Boeing 737 commercial flights have demonstrated cabin variations in radiation exposure up to 30 percent. These prior results were the basis of the present study to quantify the potential effects of aircraft construction materials on the internal exposures of the crew and passengers. The present study constitutes preflight measurements using an unmoderated Cf-252 fission neutron source to quantify the effects of three current and potential aircraft materials (aluminum, titanium, and graphite-epoxy composite) on the fast neutron flux. Conclusions about the effectiveness of the three selected materials for radiation shielding must wait until testing in the atmosphere is complete; however, it is clear that for shielding low-energy neutrons, the composite material is an improved shielding material over aluminum or titanium.

Atmospheric scattering of middle uv radiation from an internal source.

PubMed

Meier, R R; Lee, J S; Anderson, D E

1978-10-15

A Monte Carlo model has been developed which simulates the multiple-scattering of middle-uv radiation in the lower atmosphere. The source of radiation is assumed to be monochromatic and located at a point. The physical effects taken into account in the model are Rayleigh and Mie scattering, pure absorption by particulates and trace atmospheric gases, and ground albedo. The model output consists of the multiply scattered radiance as a function of look-angle of a detector located within the atmosphere. Several examples are discussed, and comparisons are made with direct-source and single-scattered contributions to the signal received by the detector.

A high-power synthesized ultrawideband radiation source

NASA Astrophysics Data System (ADS)

Efremov, A. M.; Koshelev, V. I.; Plisko, V. V.; Sevostyanov, E. A.

2017-09-01

A high-power ultrawideband radiation source has been developed which is capable of synthesizing electromagnetic pulses with different frequency bands in free space. To this end, a new circuit design comprising a four-channel former of bipolar pulses of durations 2 and 3 ns has been elaborated and conditions for the stable operation of gas gaps of independent channels without external control pulses have been determined. Each element of the 2 × 2 array of combined antennas is driven from an individual channel of the pulse former. Antennas excited by pulses of the same duration are arranged diagonally. Two radiation synthesis modes have been examined: one aimed to attain ultimate field strength and the other aimed to attain an ultimate width of the radiation spectrum. The modes were changed by changing the time delay between the 2-ns and 3-ns pulses. For the first mode, radiation pulses with a frequency band of 0.2-0.8 GHz and an effective potential of 500 kV have been obtained. The synthesized radiation pulses produced in the second mode had an extended frequency band (0.1-1 GHz) and an effective potential of 220 kV. The pulse repetition frequency was 100 Hz.

Sound source identification and sound radiation modeling in a moving medium using the time-domain equivalent source method.

PubMed

Zhang, Xiao-Zheng; Bi, Chuan-Xing; Zhang, Yong-Bin; Xu, Liang

2015-05-01

Planar near-field acoustic holography has been successfully extended to reconstruct the sound field in a moving medium, however, the reconstructed field still contains the convection effect that might lead to the wrong identification of sound sources. In order to accurately identify sound sources in a moving medium, a time-domain equivalent source method is developed. In the method, the real source is replaced by a series of time-domain equivalent sources whose strengths are solved iteratively by utilizing the measured pressure and the known convective time-domain Green's function, and time averaging is used to reduce the instability in the iterative solving process. Since these solved equivalent source strengths are independent of the convection effect, they can be used not only to identify sound sources but also to model sound radiations in both moving and static media. Numerical simulations are performed to investigate the influence of noise on the solved equivalent source strengths and the effect of time averaging on reducing the instability, and to demonstrate the advantages of the proposed method on the source identification and sound radiation modeling.

The Electron Beam Ion Source (EBIS)

ScienceCinema

Brookhaven Lab

2017-12-09

Brookhaven National Lab has successfully developed a new pre-injector system, called the Electron Beam Ion Source, for the Relativistic Heavy Ion Collider (RHIC) and NASA Space Radiation Laboratory science programs. The first of several planned improvemen

Stanford Synchrotron Radiation Laboratory activity report for 1986

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cantwell, K.

1987-12-31

1986 was another year of major advances for SSRL as the ultimate capabilities of PEP as a synchrotron radiation source became more apparent and a second PEP beam line was initiated, while effective development and utilization of SPEAR proceeded. Given these various PEP developments, SSRL abandoned its plans for a separate diffraction limited ring, as they abandoned their plans for a 6--7 GeV ring of the APS type last year. It has become increasingly apparent that SSRL should concentrate on developing SPEAR and PEP as synchrotron radiation sources. Consequently, initial planning for a 3 GeV booster synchrotron injector for SPEARmore » was performed in 1986, with a proposal to the Department of Energy resulting. As described in Chapter 2, the New Rings Group and the Machine Physics Group were combined into one Accelerator Physics Group. This group is focusing mainly on the improvement of SPEAR`s operating conditions and on planning for the conversion of PEP into a fourth generation x-ray source. Considerable emphasis is also being given to the training of accelerator physics graduate students. At the same time, several improvements of SSRL`s existing facilities were made. These are described in Chapter 3. Chapter 4 describes new SSRL beam lines being commissioned. Chapter 5 discusses SSRL`s present construction projects. Chapter 6 discusses a number of projects presently underway in the engineering division. Chapter 7 describes SSRL`s advisory panels while Chapter 8 discusses SSRL`s overall organization. Chapter 9 describes the experimental progress reports.« less

Measurements of energetic particle radiation in transit to Mars on the Mars Science Laboratory.

PubMed

Zeitlin, C; Hassler, D M; Cucinotta, F A; Ehresmann, B; Wimmer-Schweingruber, R F; Brinza, D E; Kang, S; Weigle, G; Böttcher, S; Böhm, E; Burmeister, S; Guo, J; Köhler, J; Martin, C; Posner, A; Rafkin, S; Reitz, G

2013-05-31

The Mars Science Laboratory spacecraft, containing the Curiosity rover, was launched to Mars on 26 November 2011, and for most of the 253-day, 560-million-kilometer cruise to Mars, the Radiation Assessment Detector made detailed measurements of the energetic particle radiation environment inside the spacecraft. These data provide insights into the radiation hazards that would be associated with a human mission to Mars. We report measurements of the radiation dose, dose equivalent, and linear energy transfer spectra. The dose equivalent for even the shortest round-trip with current propulsion systems and comparable shielding is found to be 0.66 ± 0.12 sievert.

Laboratory-based maximum slip rates in earthquake rupture zones and radiated energy

USGS Publications Warehouse

McGarr, A.; Fletcher, Joe B.; Boettcher, M.; Beeler, N.; Boatwright, J.

2010-01-01

Laboratory stick-slip friction experiments indicate that peak slip rates increase with the stresses loading the fault to cause rupture. If this applies also to earthquake fault zones, then the analysis of rupture processes is simplified inasmuch as the slip rates depend only on the local yield stress and are independent of factors specific to a particular event, including the distribution of slip in space and time. We test this hypothesis by first using it to develop an expression for radiated energy that depends primarily on the seismic moment and the maximum slip rate. From laboratory results, the maximum slip rate for any crustal earthquake, as well as various stress parameters including the yield stress, can be determined based on its seismic moment and the maximum slip within its rupture zone. After finding that our new equation for radiated energy works well for laboratory stick-slip friction experiments, we used it to estimate radiated energies for five earthquakes with magnitudes near 2 that were induced in a deep gold mine, an M 2.1 repeating earthquake near the San Andreas Fault Observatory at Depth (SAFOD) site and seven major earthquakes in California and found good agreement with energies estimated independently from spectra of local and regional ground-motion data. Estimates of yield stress for the earthquakes in our study range from 12 MPa to 122 MPa with a median of 64 MPa. The lowest value was estimated for the 2004 M 6 Parkfield, California, earthquake whereas the nearby M 2.1 repeating earthquake, as recorded in the SAFOD pilot hole, showed a more typical yield stress of 64 MPa.

Electromagnetic radiation from filamentary sources in the presence of axially magnetized cylindrical plasma scatterers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Es’kin, V. A.; Ivoninsky, A. V.; Kudrin, A. V., E-mail: kud@rf.unn.ru

Electromagnetic radiation from filamentary electric-dipole and magnetic-current sources of infinite length in the presence of gyrotropic cylindrical scatterers in the surrounding free space is studied. The scatterers are assumed to be infinitely long, axially magnetized circular plasma columns parallel to the axis of the filamentary source. The field and the radiation pattern of each source are calculated in the case where the source frequency is equal to one of the surface plasmon resonance frequencies of the cylindrical scatterers. It is shown that the presence of even a single resonant magnetized plasma scatterer of small electrical radius or a few suchmore » scatterers significantly affects the total fields of the filamentary sources, so that their radiation patterns become essentially different from those in the absence of scatterers or the presence of isotropic scatterers of the same shape and size. It is concluded that the radiation characteristics of the considered sources can efficiently be controlled using their resonance interaction with the neighboring gyrotropic scatterers.« less

Radiation Parameters of High Dose Rate Iridium -192 Sources

NASA Astrophysics Data System (ADS)

Podgorsak, Matthew B.

A lack of physical data for high dose rate (HDR) Ir-192 sources has necessitated the use of basic radiation parameters measured with low dose rate (LDR) Ir-192 seeds and ribbons in HDR dosimetry calculations. A rigorous examination of the radiation parameters of several HDR Ir-192 sources has shown that this extension of physical data from LDR to HDR Ir-192 may be inaccurate. Uncertainty in any of the basic radiation parameters used in dosimetry calculations compromises the accuracy of the calculated dose distribution and the subsequent dose delivery. Dose errors of up to 0.3%, 6%, and 2% can result from the use of currently accepted values for the half-life, exposure rate constant, and dose buildup effect, respectively. Since an accuracy of 5% in the delivered dose is essential to prevent severe complications or tumor regrowth, the use of basic physical constants with uncertainties approaching 6% is unacceptable. A systematic evaluation of the pertinent radiation parameters contributes to a reduction in the overall uncertainty in HDR Ir-192 dose delivery. Moreover, the results of the studies described in this thesis contribute significantly to the establishment of standardized numerical values to be used in HDR Ir-192 dosimetry calculations.

An Underappreciated Radiation Hazard from High Voltage Electrodes in Vacuum.

PubMed

West, Adam D; Lasner, Zack; DeMille, David; West, Elizabeth P; Panda, Cristian D; Doyle, John M; Gabrielse, Gerald; Kryskow, Adam; Mitchell, Corinne

2017-01-01

The use of high voltage (HV) electrodes in vacuum is commonplace in physics laboratories. In such systems, it has long been known that electron emission from an HV cathode can lead to bremsstrahlung x rays; indeed, this is the basic principle behind the operation of standard x-ray sources. However, in laboratory setups where x-ray production is not the goal and no electron source is deliberately introduced, field-emitted electrons accelerated by HV can produce x rays as an unintended hazardous byproduct. Both the level of hazard and the safe operating regimes for HV vacuum electrode systems are not widely appreciated, at least in university laboratories. A reinforced awareness of the radiation hazards associated with vacuum HV setups would be beneficial. The authors present a case study of a HV vacuum electrode device operated in a university atomic physics laboratory. They describe the characterization of the observed x-ray radiation, its relation to the observed leakage current in the device, the steps taken to contain and mitigate the radiation hazard, and suggested safety guidelines.

Radiation sources with planar wire arrays and planar foils for inertial confinement fusion and high energy density physics research

NASA Astrophysics Data System (ADS)

Kantsyrev, V. L.; Chuvatin, A. S.; Safronova, A. S.; Rudakov, L. I.; Esaulov, A. A.; Velikovich, A. L.; Shrestha, I.; Astanovitsky, A.; Osborne, G. C.; Shlyaptseva, V. V.; Weller, M. E.; Keim, S.; Stafford, A.; Cooper, M.

2014-03-01

This article reports on the joint success of two independent lines of research, each of them being a multi-year international effort. One of these is the development of innovative sources, such as planar wire arrays (PWAs). PWAs turned out to be a prolific radiator, which act mainly as a resistor, even though the physical mechanism of efficient magnetic energy conversion into radiation still remains unclear. We review the results of our extensive studies of PWAs. We also report the new results of the experimental comparison PWAs with planar foil liners (another promising alternative to wire array loads at multi-mega-ampere generators). Pioneered at UNR, the PWA Z-pinch loads have later been tested at the Sandia National Laboratories (SNL) on the Saturn generator, on GIT-12 machine in Russia, and on the QiangGuang-1 generator in China, always successfully. Another of these is the drastic improvement in energy efficiency of pulsed-power systems, which started in early 1980s with Zucker's experiments at Naval Research Laboratory (NRL). Successful continuation of this approach was the Load Current Multiplier (LCM) proposed by Chuvatin in collaboration with Rudakov and Weber from NRL. The 100 ns LCM was integrated into the Zebra generator, which almost doubled the plasma load current, from 0.9 to 1.7 MA. The two above-mentioned innovative approaches were used in combination to produce a new compact hohlraum radiation source for ICF, as jointly proposed by SNL and UNR [Jones et al., Phys. Rev. Lett. 104, 125001 (2010)]. The first successful proof-of-the-principle experimental implementation of new hohlraum concept at university-scale generator Zebra/LCM is demonstrated. A numerical simulation capability with VisRaD code (from PRISM Co.) established at UNR allowed for the study of hohlraum coupling physics and provides the possibility of optimization of a new hohlraum. Future studies are discussed.

Disposal of disused sealed radiation sources in Boreholes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vicente, R.

2007-07-01

This paper gives a description of the concept of a geological repository for disposal of disused sealed radiation sources (DSRS) under development in the Institute of Energy and Nuclear Research (IPEN), in Brazil. DSRS represent a significant fraction of total activity of radioactive wastes to be managed. Most DSRS are collected and temporarily stored at IPEN. As of 2006, the total collected activity is 800 TBq in 7,508 industrial gauge or radiotherapy sources, 7.2 TBq in about 72,000 Americium-241 sources detached from lightning rods, and about 0,5 GBq in 20,857 sources from smoke detectors. The estimated inventory of sealed sourcesmore » in the country is 2.7 hundred thousand sources with 26 PBq. The proposed repository is designed to receive the total inventory of sealed sources. A description of the pre-disposal facilities at IPEN is also presented. (authors)« less

Measuring the radiative properties of astrophysical matter using the Z X-ray source

NASA Astrophysics Data System (ADS)

Bailey, James; ZAPP Team

2017-06-01

The Z Astrophysical Plasma Properties (ZAPP) collaboration is staging Z experiments that simultaneously investigate multiple topics in radiative properties of hot dense matter. The four astrophysics questions presently guiding this research are: 1) Why can’t we predict the location of the convection zone base in the Sun?; 2) How does radiation transport affect spectrum formation in accretion-powered objects?; 3) Why doesn’t spectral fitting provide the correct properties for White Dwarfs?; and 4) Why can’t we predict the heating and charge state distribution in photoionized plasmas? Recent progress using Z, the most energetic x-ray source on earth, to address these questions will be described. We emphasize the first two topics. Opacity models are an essential ingredient of stellar models and are highly sophisticated, but laboratory opacity tests have only now become possible at the conditions existing inside stars. Our opacity research emphasizes measuring iron at conditions relevant to the base of the solar convection zone, where the electron temperature and density are believed to be 190 eV and 9x1022 e/cc, respectively. The results exhibit large disagreements between iron opacity measurements and models and ongoing research is aimed at testing hypotheses for this discrepancy. The second project is motivated by the fact that emission lines from L-shell ions are not observed from iron in black hole accretion disks, but are observed from silicon in x-ray binaries. These disparate observations may be explained by differences in the radiation transport within the plasmas, but models for the spectral line formation and transport in photoionized plasmas have never been tested. We investigate photoionized silicon plasmas using absorption spectroscopy to infer the plasma conditions and emission spectroscopy to determine the dependence of spectral emission on plasma column density.++Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed

The non-radiating component of the field generated by a finite monochromatic scalar source distribution

NASA Astrophysics Data System (ADS)

Hoenders, Bernhard J.; Ferwerda, Hedzer A.

1998-09-01

We separate the field generated by a spherically symmetric bounded scalar monochromatic source into a radiative and non-radiative part. The non-radiative part is obtained by projecting the total field on the space spanned by the non-radiating inhomogeneous modes, i.e. the modes which satisfy the inhomogeneous wave equation. Using residue techniques, introduced by Cauchy, we obtain an explicit analytical expression for the non-radiating component. We also identify the part of the source distribution which corresponds to this non-radiating part. The analysis is based on the scalar wave equation.

Development of Technologies to Utilize Laser Plasma Radiations Sources for Radiation Effects Sciences

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, J F

2007-01-31

This final report will cover work performed over the period of November 11, 2005 to September 30, 2006 on the contract to develop technologies using laser sources for radiation effects sciences. The report will discuss four topic areas; the laser source experiments on the Gekko Laser at Osaka, Japan, planning for the Charge State Freeze Out experiments to be performed in calendar year 2007, a review of previous xenon gasbags on the LANL Trident laser to provide planning support to the May-June 2007 HELEN experiments.

PLACE: an open-source python package for laboratory automation, control, and experimentation.

PubMed

Johnson, Jami L; Tom Wörden, Henrik; van Wijk, Kasper

2015-02-01

In modern laboratories, software can drive the full experimental process from data acquisition to storage, processing, and analysis. The automation of laboratory data acquisition is an important consideration for every laboratory. When implementing a laboratory automation scheme, important parameters include its reliability, time to implement, adaptability, and compatibility with software used at other stages of experimentation. In this article, we present an open-source, flexible, and extensible Python package for Laboratory Automation, Control, and Experimentation (PLACE). The package uses modular organization and clear design principles; therefore, it can be easily customized or expanded to meet the needs of diverse laboratories. We discuss the organization of PLACE, data-handling considerations, and then present an example using PLACE for laser-ultrasound experiments. Finally, we demonstrate the seamless transition to post-processing and analysis with Python through the development of an analysis module for data produced by PLACE automation. © 2014 Society for Laboratory Automation and Screening.

Production of photoionized plasmas in the laboratory with x-ray line radiation

NASA Astrophysics Data System (ADS)

White, S.; Irwin, R.; Warwick, J. R.; Gribakin, G. F.; Sarri, G.; Keenan, F. P.; Riley, D.; Rose, S. J.; Hill, E. G.; Ferland, G. J.; Han, B.; Wang, F.; Zhao, G.

2018-06-01

In this paper we report the experimental implementation of a theoretically proposed technique for creating a photoionized plasma in the laboratory using x-ray line radiation. Using a Sn laser plasma to irradiate an Ar gas target, the photoionization parameter, ξ =4 π F /Ne , reached values of order 50 ergcm s-1 , where F is the radiation flux in ergc m-2s-1 . The significance of this is that this technique allows us to mimic effective spectral radiation temperatures in excess of 1 keV. We show that our plasma starts to be collisionally dominated before the peak of the x-ray drive. However, the technique is extendable to higher-energy laser systems to create plasmas with parameters relevant to benchmarking codes used to model astrophysical objects.

openBIS ELN-LIMS: an open-source database for academic laboratories.

PubMed

Barillari, Caterina; Ottoz, Diana S M; Fuentes-Serna, Juan Mariano; Ramakrishnan, Chandrasekhar; Rinn, Bernd; Rudolf, Fabian

2016-02-15

The open-source platform openBIS (open Biology Information System) offers an Electronic Laboratory Notebook and a Laboratory Information Management System (ELN-LIMS) solution suitable for the academic life science laboratories. openBIS ELN-LIMS allows researchers to efficiently document their work, to describe materials and methods and to collect raw and analyzed data. The system comes with a user-friendly web interface where data can be added, edited, browsed and searched. The openBIS software, a user guide and a demo instance are available at https://openbis-eln-lims.ethz.ch. The demo instance contains some data from our laboratory as an example to demonstrate the possibilities of the ELN-LIMS (Ottoz et al., 2014). For rapid local testing, a VirtualBox image of the ELN-LIMS is also available. © The Author 2015. Published by Oxford University Press.

Space shuttle L-tube radiator testing

NASA Technical Reports Server (NTRS)

Phillips, M. A.

1976-01-01

A series of tests were conducted to support the development of the Orbiter Heat Rejection System. The details of the baseline radiator were defined by designing, fabricating, and testing representative hardware. The tests were performed in the Space Environmental Simulation Laboratory Chamber A. An IR source was used to simulate total solar and infrared environmental loads on the flowing shuttle radiators panel. The thermal and mechanical performance of L tube space radiators and their thermal coating were established.

Inertial confinement fusion method producing line source radiation fluence

DOEpatents

Rose, Ronald P.

1984-01-01

An inertial confinement fusion method in which target pellets are imploded in sequence by laser light beams or other energy beams at an implosion site which is variable between pellet implosions along a line. The effect of the variability in position of the implosion site along a line is to distribute the radiation fluence in surrounding reactor components as a line source of radiation would do, thereby permitting the utilization of cylindrical geometry in the design of the reactor and internal components.

Report: Results of Technical Network Vulnerability Assessment: EPA’s Radiation and Indoor Environments National Laboratory

EPA Pesticide Factsheets

Report #09-P-0053, December 9, 2008. Vulnerability testing of EPA’s Radiation and Indoor Environments National Laboratory (R&IEN) network identified Internet Protocol addresses with medium-risk vulnerabilities.

Radiation drag in the field of a non-spherical source

NASA Astrophysics Data System (ADS)

Bini, D.; Geralico, A.; Passamonti, A.

2015-01-01

The motion of a test particle in the gravitational field of a non-spherical source endowed with both mass and mass quadrupole moment is investigated when a test radiation field is also present. The background is described by the Erez-Rosen solution, which is a static space-time belonging to the Weyl class of solutions to the vacuum Einstein's field equations, and reduces to the familiar Schwarzschild solution when the quadrupole parameter vanishes. The radiation flux has a fixed but arbitrary (non-zero) angular momentum. The interaction with the radiation field is assumed to be Thomson-like, i.e. the particles absorb and re-emit radiation, thus suffering for a friction-like drag force. Such an additional force is responsible for the Poynting-Robertson effect, which is well established in the framework of Newtonian gravity and has been recently extended to the general theory of relativity. The balance between gravitational attraction, centrifugal force and radiation drag leads to the occurrence of equilibrium circular orbits which are attractors for the surrounding matter for every fixed value of the interaction strength. The presence of the quadrupolar structure of the source introduces a further degree of freedom: there exists a whole family of equilibrium orbits parametrized by the quadrupole parameter, generalizing previous works. This scenario is expected to play a role in the context of accretion matter around compact objects.

Design Considerations of a Virtual Laboratory for Advanced X-ray Sources

NASA Astrophysics Data System (ADS)

Luginsland, J. W.; Frese, M. H.; Frese, S. D.; Watrous, J. J.; Heileman, G. L.

2004-11-01

The field of scientific computation has greatly advanced in the last few years, resulting in the ability to perform complex computer simulations that can predict the performance of real-world experiments in a number of fields of study. Among the forces driving this new computational capability is the advent of parallel algorithms, allowing calculations in three-dimensional space with realistic time scales. Electromagnetic radiation sources driven by high-voltage, high-current electron beams offer an area to further push the state-of-the-art in high fidelity, first-principles simulation tools. The physics of these x-ray sources combine kinetic plasma physics (electron beams) with dense fluid-like plasma physics (anode plasmas) and x-ray generation (bremsstrahlung). There are a number of mature techniques and software packages for dealing with the individual aspects of these sources, such as Particle-In-Cell (PIC), Magneto-Hydrodynamics (MHD), and radiation transport codes. The current effort is focused on developing an object-oriented software environment using the Rational© Unified Process and the Unified Modeling Language (UML) to provide a framework where multiple 3D parallel physics packages, such as a PIC code (ICEPIC), a MHD code (MACH), and a x-ray transport code (ITS) can co-exist in a system-of-systems approach to modeling advanced x-ray sources. Initial software design and assessments of the various physics algorithms' fidelity will be presented.

Radiation efficiency of earthquake sources at different hierarchical levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kocharyan, G. G., E-mail: gevorgkidg@mail.ru; Moscow Institute of Physics and Technology

Such factors as earthquake size and its mechanism define common trends in alteration of radiation efficiency. The macroscopic parameter that controls the efficiency of a seismic source is stiffness of fault or fracture. The regularities of this parameter alteration with scale define several hierarchical levels, within which earthquake characteristics obey different laws. Small variations of physical and mechanical properties of the fault principal slip zone can lead to dramatic differences both in the amplitude of released stress and in the amount of radiated energy.

Enabling three-dimensional densitometric measurements using laboratory source X-ray micro-computed tomography

NASA Astrophysics Data System (ADS)

Pankhurst, M. J.; Fowler, R.; Courtois, L.; Nonni, S.; Zuddas, F.; Atwood, R. C.; Davis, G. R.; Lee, P. D.

2018-01-01

We present new software allowing significantly improved quantitative mapping of the three-dimensional density distribution of objects using laboratory source polychromatic X-rays via a beam characterisation approach (c.f. filtering or comparison to phantoms). One key advantage is that a precise representation of the specimen material is not required. The method exploits well-established, widely available, non-destructive and increasingly accessible laboratory-source X-ray tomography. Beam characterisation is performed in two stages: (1) projection data are collected through a range of known materials utilising a novel hardware design integrated into the rotation stage; and (2) a Python code optimises a spectral response model of the system. We provide hardware designs for use with a rotation stage able to be tilted, yet the concept is easily adaptable to virtually any laboratory system and sample, and implicitly corrects the image artefact known as beam hardening.

Spectroscopy of X-ray Photoionized Plasmas in the Laboratory

NASA Astrophysics Data System (ADS)

Liedahl, Duane A.; Loisel, Guillaume; Bailey, James E.; Nagayama, Taisuke; Hansen, Stephanie B.; Rochau, Gregory; Fontes, Christopher J.; Mancini, Roberto; Kallman, Timothy R.

2018-06-01

The physical processes operating in astrophysical plasmas --- heating, cooling, ionization, recombination, level population kinetics, and radiation transport --- are all accessible to observation in the laboratory. What distinguishes X-ray photoionized plasmas from the more common case of high-temperature collisionally-ionized plasmas is the elevated level of importance of the radiation/matter interaction. The advent of laboratory facilities with the capability to generate high-powered X-ray sources has provided the means by which to study this interaction, which is also fundamental to active galactic nuclei and other accretion-powered objects. We discuss recent and ongoing experiments, with an emphasis on X-ray spectroscopic measurements of silicon plasmas obtained at the Sandia Z Pulsed Power Facility.

Radiation anomaly detection algorithms for field-acquired gamma energy spectra

NASA Astrophysics Data System (ADS)

Mukhopadhyay, Sanjoy; Maurer, Richard; Wolff, Ron; Guss, Paul; Mitchell, Stephen

2015-08-01

The Remote Sensing Laboratory (RSL) is developing a tactical, networked radiation detection system that will be agile, reconfigurable, and capable of rapid threat assessment with high degree of fidelity and certainty. Our design is driven by the needs of users such as law enforcement personnel who must make decisions by evaluating threat signatures in urban settings. The most efficient tool available to identify the nature of the threat object is real-time gamma spectroscopic analysis, as it is fast and has a very low probability of producing false positive alarm conditions. Urban radiological searches are inherently challenged by the rapid and large spatial variation of background gamma radiation, the presence of benign radioactive materials in terms of the normally occurring radioactive materials (NORM), and shielded and/or masked threat sources. Multiple spectral anomaly detection algorithms have been developed by national laboratories and commercial vendors. For example, the Gamma Detector Response and Analysis Software (GADRAS) a one-dimensional deterministic radiation transport software capable of calculating gamma ray spectra using physics-based detector response functions was developed at Sandia National Laboratories. The nuisance-rejection spectral comparison ratio anomaly detection algorithm (or NSCRAD), developed at Pacific Northwest National Laboratory, uses spectral comparison ratios to detect deviation from benign medical and NORM radiation source and can work in spite of strong presence of NORM and or medical sources. RSL has developed its own wavelet-based gamma energy spectral anomaly detection algorithm called WAVRAD. Test results and relative merits of these different algorithms will be discussed and demonstrated.

Radiation effects on MOS devices - dosimetry, annealing, irradiation sequence, and sources

NASA Technical Reports Server (NTRS)

Stassinopoulos, E. G.; Brucker, G. J.; Van Gunten, O.; Knudson, A. R.; Jordan, T. M.

1983-01-01

This paper reports on some investigations of dosimetry, annealing, irradiation sequences, and radioactive sources, involved in the determination of radiation effects on MOS devices. Results show that agreement in the experimental and theoretical surface to average doses support the use of thermo-luminescent dosimeters (manganese activated calcium fluoride) in specifying the surface dose delivered to thin gate insulators of MOS devices. Annealing measurements indicate the existence of at least two energy levels,,s or a activation energies, for recovery of soft oxide MOS devices after irradiation by electrons, protons, and gammas. Damage sensitivities of MOS devices were found to be independent of combinations and sequences of radiation type or energies. Comparison of various gamma sources indicated a small dependence of damage sensitivity on the Cobalt facility, but a more significant dependence in the case of the Cesium source. These results were attributed to differences in the spectral content of the several sources.

International workshop on cold neutron sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russell, G.J.; West, C.D.

1991-08-01

The first meeting devoted to cold neutron sources was held at the Los Alamos National Laboratory on March 5--8, 1990. Cosponsored by Los Alamos and Oak Ridge National Laboratories, the meeting was organized as an International Workshop on Cold Neutron Sources and brought together experts in the field of cold-neutron-source design for reactors and spallation sources. Eighty-four people from seven countries attended. Because the meeting was the first of its kind in over forty years, much time was spent acquainting participants with past and planned activities at reactor and spallation facilities worldwide. As a result, the meeting had more ofmore » a conference flavor than one of a workshop. The general topics covered at the workshop included: Criteria for cold source design; neutronic predictions and performance; energy deposition and removal; engineering design, fabrication, and operation; material properties; radiation damage; instrumentation; safety; existing cold sources; and future cold sources.« less

32 CFR 655.10 - Use of radiation sources by non-Army entities on Army land (AR 385-11).

Code of Federal Regulations, 2010 CFR

2010-07-01

... radioisotope; or (5) A machine-produced ionizing-radiation source capable of producing an area, accessible to... NARM and machine-produced ionizing radiation sources, the applicant has an appropriate State... 32 National Defense 4 2010-07-01 2010-07-01 true Use of radiation sources by non-Army entities on...

Saturn Neutron Exosphere as Source for Inner and Innermost Radiation Belts

NASA Technical Reports Server (NTRS)

Cooper, John; Lipatov, Alexander; Sittler, Edward; Sturner, Steven

2011-01-01

Energetic proton and electron measurements by the ongoing Cassini orbiter mission are expanding our knowledge of the highest energy components of the Saturn magnetosphere in the inner radiation belt region after the initial discoveries of these belts by the Pioneer 11 and Voyager 2 missions. Saturn has a neutron exosphere that extends throughout the magnetosphere from the cosmic ray albedo neutron source at the planetary main rings and atmosphere. The neutrons emitted from these sources at energies respectively above 4 and 8 eV escape the Saturn system, while those at lower energies are gravitationally bound. The neutrons undergo beta decay in average times of about 1000 seconds to provide distributed sources of protons and electrons throughout Saturn's magnetosphere with highest injection rates close to the Saturn and ring sources. The competing radiation belt source for energetic electrons is rapid inward diffusion and acceleration of electrons from the middle magnetosphere and beyond. Minimal losses during diffusive transport across the moon orbits, e.g. of Mimas and Enceladus, and local time asymmetries in electron intensity, suggest that drift resonance effects preferentially boost the diffusion rates of electrons from both sources. Energy dependences of longitudinal gradient-curvature drift speeds relative to the icy moons are likely responsible for hemispheric differences (e.g., Mimas, Tethys) in composition and thermal properties as at least partly produced by radiolytic processes. A continuing mystery is the similar radial profiles of lower energy (<10 MeV) protons in the inner belt region. Either the source of these lower energy protons is also neutron decay, but perhaps alternatively from atmospheric albedo, or else all protons from diverse distributed sources are similarly affected by losses at the moon' orbits, e.g. because the proton diffusion rates are extremely low. Enceladus cryovolcanism, and radiolytic processing elsewhere on the icy moon and

Potential for improved radiation thermometry measurement uncertainty through implementing a primary scale in an industrial laboratory

NASA Astrophysics Data System (ADS)

Willmott, Jon R.; Lowe, David; Broughton, Mick; White, Ben S.; Machin, Graham

2016-09-01

A primary temperature scale requires realising a unit in terms of its definition. For high temperature radiation thermometry in terms of the International Temperature Scale of 1990 this means extrapolating from the signal measured at the freezing temperature of gold, silver or copper using Planck’s radiation law. The difficulty in doing this means that primary scales above 1000 °C require specialist equipment and careful characterisation in order to achieve the extrapolation with sufficient accuracy. As such, maintenance of the scale at high temperatures is usually only practicable for National Metrology Institutes, and calibration laboratories have to rely on a scale calibrated against transfer standards. At lower temperatures it is practicable for an industrial calibration laboratory to have its own primary temperature scale, which reduces the number of steps between the primary scale and end user. Proposed changes to the SI that will introduce internationally accepted high temperature reference standards might make it practicable to have a primary high temperature scale in a calibration laboratory. In this study such a scale was established by calibrating radiation thermometers directly to high temperature reference standards. The possible reduction in uncertainty to an end user as a result of the reduced calibration chain was evaluated.

Experimental verification of isotropic radiation from a coherent dipole source via electric-field-driven LC resonator metamaterials.

PubMed

Tichit, Paul-Henri; Burokur, Shah Nawaz; Qiu, Cheng-Wei; de Lustrac, André

2013-09-27

It has long been conjectured that isotropic radiation by a simple coherent source is impossible due to changes in polarization. Though hypothetical, the isotropic source is usually taken as the reference for determining a radiator's gain and directivity. Here, we demonstrate both theoretically and experimentally that an isotropic radiator can be made of a simple and finite source surrounded by electric-field-driven LC resonator metamaterials designed by space manipulation. As a proof-of-concept demonstration, we show the first isotropic source with omnidirectional radiation from a dipole source (applicable to all distributed sources), which can open up several possibilities in axion electrodynamics, optical illusion, novel transformation-optic devices, wireless communication, and antenna engineering. Owing to the electric- field-driven LC resonator realization scheme, this principle can be readily applied to higher frequency regimes where magnetism is usually not present.

Modeling of radiative properties of Sn plasmas for extreme-ultraviolet source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sasaki, Akira; Sunahara, Atsushi; Furukawa, Hiroyuki

Atomic processes in Sn plasmas are investigated for application to extreme-ultraviolet (EUV) light sources used in microlithography. We develop a full collisional radiative (CR) model of Sn plasmas based on calculated atomic data using Hebrew University Lawrence Livermore Atomic Code (HULLAC). Resonance and satellite lines from singly and multiply excited states of Sn ions, which contribute significantly to the EUV emission, are identified and included in the model through a systematic investigation of their effect on the emission spectra. The wavelengths of the 4d-4f+4p-4d transitions of Sn{sup 5+} to Sn{sup 13+} are investigated, because of their importance for determining themore » conversion efficiency of the EUV source, in conjunction with the effect of configuration interaction in the calculation of atomic structure. Calculated emission spectra are compared with those of charge exchange spectroscopy and of laser produced plasma EUV sources. The comparison is also carried out for the opacity of a radiatively heated Sn sample. A reasonable agreement is obtained between calculated and experimental EUV emission spectra observed under the typical condition of EUV sources with the ion density and ionization temperature of the plasma around 10{sup 18} cm{sup -3} and 20 eV, respectively, by applying a wavelength correction to the resonance and satellite lines. Finally, the spectral emissivity and opacity of Sn plasmas are calculated as a function of electron temperature and ion density. The results are useful for radiation hydrodynamics simulations for the optimization of EUV sources.« less

Nanoseismic sources made in the laboratory: source kinematics and time history

NASA Astrophysics Data System (ADS)

McLaskey, G.; Glaser, S. D.

2009-12-01

When studying seismic signals in the field, the analysis of source mechanisms is always obscured by propagation effects such as scattering and reflections due to the inhomogeneous nature of the earth. To get around this complication, we measure seismic waves (wavelengths from 2 mm to 300 mm) in laboratory-sized specimens of extremely homogeneous isotropic materials. We are able to study the focal mechanism and time history of nanoseismic sources produced by fracture, impact, and sliding friction, roughly six orders of magnitude smaller and more rapid than typical earthquakes. Using very sensitive broadband conical piezoelectric sensors, we are able to measure surface normal displacements down to a few pm (10^-12 m) in amplitude. Thick plate specimens of homogeneous materials such as glass, steel, gypsum, and polymethylmethacrylate (PMMA) are used as propagation media in the experiments. Recorded signals are in excellent agreement with theoretically determined Green’s functions obtained from a generalized ray theory code for an infinite plate geometry. Extremely precise estimates of the source time history are made via full waveform inversion from the displacement time histories recorded by an array of at least ten sensors. Each channel is sampled at a rate of 5 MHz. The system is absolutely calibrated using the normal impact of a tiny (~1 mm) ball on the surface of the specimen. The ball impact induces a force pulse into the specimen a few ms in duration. The amplitude, duration, and shape of the force pulse were found to be well approximated by Hertzian-derived impact theory, while the total change in momentum of the ball is independently measured from its incoming and rebound velocities. Another calibration source, the sudden fracture of a thin-walled glass capillary tube laid on its side and loaded against the surface of the specimen produces a similar point force, this time with a source function very nearly a step in time with rise time of less than 500 ns

EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

EPA Science Inventory

The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

A Review of Radiation Protection Solutions for the Staff in the Cardiac Catheterisation Laboratory.

PubMed

Badawy, Mohamed Khaldoun; Deb, Pradip; Chan, Robert; Farouque, Omar

2016-10-01

Adverse health effects of radiation exposure to staff in cardiac catheterisation laboratories have been well documented in the literature. Examples include increased risk of cataracts as well as possible malignancies. These risks can be partly mitigated by reducing scatter radiation exposure to staff during diagnostic and interventional cardiac procedures. There are currently commercially available radiation protection tools, including radioprotective caps, gloves, eyewear, thyroid collars, aprons, mounted shields, table skirts and patient drapes to protect staff from excessive radiation exposure. Furthermore, real-time dose feedback could lead to procedural changes that reduce operator dose. The objective of this review is to examine the efficacy of these tools and provide practical recommendations to reduce occupational radiation exposure with the aim of minimising long-term adverse health outcomes. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Impedance loading and radiation of finite aperture multipole sources in fluid filled boreholes

NASA Astrophysics Data System (ADS)

Geerits, Tim W.; Kranz, Burkhard

2017-04-01

In the exploration of oil and gas finite aperture multipole borehole acoustic sources are commonly used to excite borehole modes in a fluid-filled borehole surrounded by a (poro-) elastic formation. Due to the mutual interaction of the constituent sources and their immediate proximity to the formation it has been unclear how and to what extent these effects influence radiator performance. We present a theory, based on the equivalent surface source formulation for fluid-solid systems that incorporates these 'loading' effects and allows for swift computation of the multipole source dimensionless impedance, the associated radiator motion and the resulting radiated wave field in borehole fluid and formation. Dimensionless impedance results are verified through a comparison with finite element modeling results in the cases of a logging while drilling tool submersed in an unbounded fluid and a logging while drilling tool submersed in a fluid filled borehole surrounded by a fast and a slow formation. In all these cases we consider a monopole, dipole and quadrupole excitation, as these cases are relevant to many borehole acoustic applications. Overall, we obtain a very good agreement.

Laboratory simulation of Hg0 emissions from a snowpack.

PubMed

Dommergue, Aurélien; Bahlmann, Enno; Ebinghaus, Ralf; Ferrari, Christophe; Boutron, Claude

2007-05-01

Snow surfaces play an important role in the biogeochemical cycle of mercury in high-latitude regions. Snowpacks act both as sources and sinks for gaseous compounds. Surprisingly, the roles of each environmental parameter that can govern the air-surface exchange over snow are not well understood owing to the lack of systematic studies. A laboratory system called the laboratory flux measurement system was used to study the emission of gaseous elemental mercury from a natural snowpack under controlled conditions. The first results from three snowpacks originating from alpine, urban and polar areas are presented. Consistent with observations in the field, we were able to reproduce gaseous mercury emissions and showed that they are mainly driven by solar radiation and especially UV-B radiation. From these laboratory experiments, we derived kinetic constants which show that divalent mercury can have a short natural lifetime of about 4-6 h in snow.

Radiation resistant PIDECα cell using photon intermediate direct energy conversion and a 210Po source.

PubMed

Weaver, Charles L; Schott, Robert J; Prelas, Mark A; Wisniewski, Denis A; Rothenberger, Jason B; Lukosi, Eric D; Oh, Kyuhak

2018-02-01

Radiation damage is a significant concern with both alphavoltaic and betavoltaic cells because their performance degrades, especially with high-energy - (>200keV) beta and alpha particles. Indirect excitation methods, such as the Photon Intermediate Direct Energy Conversion (PIDEC) framework, can protect the transducer from radiation. A nuclear battery using a 90 Sr beta source was constructed by the author's research group, which demonstrated the radiation resistance of a PIDEC cell driven by beta particles (PIDECβ cell). Use of alpha sources to drive nuclear batteries would appear to be much more attractive than beta sources due to higher potential power density. However, they are also subject to higher rates of radiation damage. This paper describes the successful incorporation of alpha particles into the PIDEC framework using the alpha emitter 210 Po to form a PIDECα cell. The PIDECα cell transducer was exposed to alpha particles for over one year without experiencing adverse effects from radiation damage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Micromachined TWTs for THz Radiation Sources

NASA Technical Reports Server (NTRS)

Booske, John H.; vanderWeide, Daniel W.; Kory, Carol L.; Limbach, S.; Downey, Alan (Technical Monitor)

2001-01-01

The Terahertz (THz) region of the electromagnetic spectrum (about 300 - 3000 GHz in frequency or about 0.1 - 1 mm free space wavelength) has enormous potential for high-data-rate communications, spectroscopy, astronomy, space research, medicine, biology, surveillance, remote sensing, industrial process control, etc. It has been characterized as the most scientifically rich, yet under-utilized, region of the electromagnetic spectrum. The most critical roadblock to full exploitation of the THz band is lack of coherent radiation sources that are powerful (0.001 - 1.0 W continuous wave), efficient (> 1%), frequency agile (instantaneously tunable over 1% bandwidths or more), reliable, and comparatively inexpensive. To develop vacuum electron device (VED) radiation sources satisfying these requirements, fabrication and packaging approaches must be heavily considered to minimize costs, in addition to the basic interaction physics and circuit design. To minimize size of the prime power supply, beam voltage must be minimized, preferably 10 kV. Solid state sources satisfy the low voltage requirement, but are many orders of magnitude below power, efficiency, and bandwidth requirements. On the other hand, typical fast-wave VED sources in this regime (e.g., gyrotrons, FELs) tend to be large, expensive, high voltage and very high power devices unsuitable for most of the applications cited above. VEDs based on grating or inter-digital (ID) circuits have been researched and developed. However, achieving forward-wave amplifier operation with instantaneous fractional bandwidths > 1% is problematic for these devices with low-energy (< 15 kV) electron beams. Moreover, the interaction impedance is quite low unless the beam-circuit spacing is kept particularly narrow, often leading to significant beam interception. One solution to satisfy the THz source requirements mentioned above is to develop micromachined VEDs, or "micro-VEDs". Among other benefits, micro-machining technologies

Sulfate Aerosol in the Arctic: Source Attribution and Radiative Forcing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Yang; Wang, Hailong; Smith, Steven J.

Source attributions of Arctic sulfate and its direct radiative effect for 2010–2014 are quantified in this study using the Community Earth System Model (CESM) equipped with an explicit sulfur source-tagging technique. Regions that have high emissions and/or are near/within the Arctic present relatively large contributions to Arctic sulfate burden, with the largest contribution from sources in East Asia (27%). East Asia and South Asia together have the largest contributions to Arctic sulfate concentrations at 9–12 km, whereas sources within or near the Arctic account largely below 2 km. For remote sources with strong emissions, their contributions to Arctic sulfate burdenmore » are primarily driven by meteorology, while contributions of sources within or near the Arctic are dominated by their emission strength. The sulfate direct radiative effect (DRE) is –0.080 W m-2 at the Arctic surface, offsetting the net warming effect from the combination of in-snow heating and DRE cooling from black carbon. East Asia, Arctic local and Russia/Belarus/Ukraine sources contribute –0.017, –0.016 and –0.014 W m-2, respectively, to Arctic sulfate DRE. A 20% reduction in anthropogenic SO2 emissions leads to a net increase of +0.013 W m-2 forcing at the Arctic surface. These results indicate that a joint reduction in BC emissions could prevent possible Arctic warming from future reductions in SO2 emissions. Sulfate DRE efficiency calculations suggest that short transport pathways together with meteorology favoring long sulfate lifetimes make certain sources more efficient in influencing the Arctic sulfate DRE.« less

Auroral kilometric radiation: Wave modes, harmonic and source region electron density structures

NASA Technical Reports Server (NTRS)

Benson, R. F.

1984-01-01

A change from extraordinary (X) mode to ordinary (0) mode dominance is observed in the auroral kilometric radiation (AKR) detected on ISIS 1 topside sounder ionograms as the source region plasma to gyrofrequency ratio fN/fH varies from 0.1 to 1.3. The X and 0 mode AKR, Z (the slow branch of the X mode) and whistler (W) mode are also observed. The Z mode is typically slightly less intense than the 0-mode. Thw W-mode is confined to frequencies less than fH/2, suggesting that it is the result of field aligned ducted signals reaching the satellite from a source at lower altitudes. Harmonic AKR bands are commonly observed and the 2nd harmonic appears to be due to propagating signals. The deduced (fN/fH) at the bottom of the AKR source region is always less than 0.4 and is typically less than 0.2 during the generation of X-mode AKR, but approaches 0.9 for 0-mode AKR. No large density enhancements were observed within AKR source region density cavities. It is suggested that the observed INTENSE AKR IS cyclotron X-mode radiation rather than plasma frequency 0-mode radiation.

Convection induced by selective absorption of radiation: A laboratory model of conditional instability

NASA Astrophysics Data System (ADS)

Krishnamurti, Ruby

1998-01-01

When there is internal heating in a fluid layer, convection can occur even if the static state is one of stable stratification. We have been investigating through laboratory experiments such a stably stratified layer of water which is heated above and cooled below. The water contains in dilute solution thymol blue (a pH indicator), which normally colors the water orange. It turns yellow if the pH is low, blue if the pH is high. A small DC voltage is applied across the layer, by using the bottom boundary as the positive electrode, the top boundary as the negative electrode. The hydroxyl ions formed near the bottom boundary cause the orange fluid to turn blue. The fluid layer is uniformly and steadily illuminated from above with light from a sodium vapor lamp. This radiation travels with negligible absorption through the orange fluid but is strongly absorbed by the blue fluid. The resultant warming of the blue fluid can lead to convective instability, with the blue fluid rising into warm upper layers, which it would continue to penetrate as long as it remains blue and as long as the radiative heating is sufficient to exceed the higher ambient temperatures above. This radiative heating occurs only in the blue rising flow; the sinking fluid is orange and is not heated. We have found that with a strongly stably stratified layer, convective plumes are unable to penetrate far and they remain shallow. However, for a weakly stratified layer, plumes grow tall and furthermore collect into a large convective cluster which persists as a steady coherent structure. The present paper deals also with the formulation of the governing equations to include the fluid-state-dependent heat source. A linear stability analysis shows that the critical Rayleigh number for onset of motion is drastically reduced. Furthermore, the cell size at onset is larger by a factor of √ 3/2 than in the classical Rayleigh-Benard convection problem. However, the laboratory fluid cells were much further

ATTENUATION OF COBALT-60 RADIATION FROM A SOURCE DISTRIBUTED AROUND A CONCRETE BLOCKHOUSE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Batter, J.F.; Starbird, A.W.

1961-06-15

Two radiation-shielding experiments were performed upon a simple blockhouse structure. The blockhouse was exposed to a simulated fallout field, and the radiation penetrating the structure was measured. The radiation field was produced by circulating a sealed cobalt-60 source through polyethylene tubing predistributed over an octant centered on the test building. Experimental details are described and results tabulated. (auth)

Reflectivity of the atmosphere-inhomogeneous surfaces system Laboratory simulation

NASA Technical Reports Server (NTRS)

Mekler, Y.; Kaufman, Y. J.; Fraser, R. S.

1984-01-01

Theoretical two- and three-dimensional solutions of the radiative transfer equation have been applied to the earth-atmosphere system. Such solutions have not been verified experimentally. A laboratory experiment simulates such a system to test the theory. The atmosphere was simulated by latex spheres suspended in water and the ground by a nonuniform surface, half white and half black. A stable radiation source provided uniform illumination over the hydrosol. The upward radiance along a line orthogonal to the boundary of the two-halves field was recorded for different amounts of the hydrosol. The simulation is a well-defined radiative transfer experiment to test radiative transfer models involving nonuniform surfaces. Good agreement is obtained between the measured and theoretical results.

X-ray intensity and source size characterizations for the 25 kV upgraded Manson source at Sandia National Laboratories

NASA Astrophysics Data System (ADS)

Loisel, G.; Lake, P.; Gard, P.; Dunham, G.; Nielsen-Weber, L.; Wu, M.; Norris, E.

2016-11-01

At Sandia National Laboratories, the x-ray generator Manson source model 5 was upgraded from 10 to 25 kV. The purpose of the upgrade is to drive higher characteristics photon energies with higher throughput. In this work we present characterization studies for the source size and the x-ray intensity when varying the source voltage for a series of K-, L-, and M-shell lines emitted from Al, Y, and Au elements composing the anode. We used a 2-pinhole camera to measure the source size and an energy dispersive detector to monitor the spectral content and intensity of the x-ray source. As the voltage increases, the source size is significantly reduced and line intensity is increased for the three materials. We can take advantage of the smaller source size and higher source throughput to effectively calibrate the suite of Z Pulsed Power Facility crystal spectrometers.

Translation of Atherosclerotic Plaque Phase-Contrast CT Imaging from Synchrotron Radiation to a Conventional Lab-Based X-Ray Source

PubMed Central

Saam, Tobias; Herzen, Julia; Hetterich, Holger; Fill, Sandra; Willner, Marian; Stockmar, Marco; Achterhold, Klaus; Zanette, Irene; Weitkamp, Timm; Schüller, Ulrich; Auweter, Sigrid; Adam-Neumair, Silvia; Nikolaou, Konstantin; Reiser, Maximilian F.; Pfeiffer, Franz; Bamberg, Fabian

2013-01-01

Objectives Phase-contrast imaging is a novel X-ray based technique that provides enhanced soft tissue contrast. The aim of this study was to evaluate the feasibility of visualizing human carotid arteries by grating-based phase-contrast tomography (PC-CT) at two different experimental set-ups: (i) applying synchrotron radiation and (ii) using a conventional X-ray tube. Materials and Methods Five ex-vivo carotid artery specimens were examined with PC-CT either at the European Synchrotron Radiation Facility using a monochromatic X-ray beam (2 specimens; 23 keV; pixel size 5.4 µm), or at a laboratory set-up on a conventional X-ray tube (3 specimens; 35-40 kVp; 70 mA; pixel size 100 µm). Tomographic images were reconstructed and compared to histopathology. Two independent readers determined vessel dimensions and one reader determined signal-to-noise ratios (SNR) between PC-CT and absorption images. Results In total, 51 sections were included in the analysis. Images from both set-ups provided sufficient contrast to differentiate individual vessel layers. All PCI-based measurements strongly predicted but significantly overestimated lumen, intima and vessel wall area for both the synchrotron and the laboratory-based measurements as compared with histology (all p<0.001 with slope >0.53 per mm2, 95%-CI: 0.35 to 0.70). Although synchrotron-based images were characterized by higher SNRs than laboratory-based images; both PC-CT set-ups had superior SNRs compared to corresponding conventional absorption-based images (p<0.001). Inter-reader reproducibility was excellent (ICCs >0.98 and >0.84 for synchrotron and for laboratory-based measurements; respectively). Conclusion Experimental PC-CT of carotid specimens is feasible with both synchrotron and conventional X-ray sources, producing high-resolution images suitable for vessel characterization and atherosclerosis research. PMID:24039969

Selected bibliography of terrestrial freshwater, and marine radiation ecology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schultz, V.; Whicker, F.W.

1975-01-01

An extensive bibliography is presented of publications related to field or laboratory studies of wild species of plants and animals with respect to radiation effects or metabolic studies involving radionuclides. The references are listed under the following headings: status and needs of radiation ecology; environmental radioactivity; radionuclide concentration; ionizing radiation effects; techniques utilizing radionuclides and ionizing radiation in ecology; measurement of ionizing radiation; peaceful uses of atomic energy; waste disposal; nuclear testing and ecological consequences of a nuclear war; glossaries, standards, and licensing procedures; reviews of radionuclides in the environment; and sources of information. (HLW)

Mars science laboratory radiation assessment detector (MSL/RAD) modeling workshop proceedings

NASA Astrophysics Data System (ADS)

Hassler, Donald M.; Norbury, John W.; Reitz, Günther

2017-08-01

The Radiation Assessment Detector (RAD) (Hassler et al., 2012; Zeitlin et al., 2016) onboard the Mars Science Laboratory (MSL) Curiosity rover (Grotzinger et al., 2012) is a sophisticated charged and neutral particle radiation analyzer developed by an international team of scientists and engineers from Southwest Research Institute in Boulder, Colorado as the leading institution, the University of Kiel and the German Aerospace Center in Cologne, Germany. RAD is a compact, powerful instrument capable of distinguishing between ionizing particles and neutral particles and providing neutron, gamma, and charged particle spectra from protons to iron as well as absorbed dose measurements in tissue-equivalent material. During the 6 month cruise to Mars, inside the MSL spacecraft, RAD served as a proxy to validate models of the radiation levels expected inside a spacecraft that future astronauts might experience (Zeitlin et al., 2013). RAD was turned on one day after the landing on August 7, 2012, exactly 100 years to the day after the discovery of cosmic rays on Earth by Victor Hess. These measurements are the first of their kind on the surface of another planet (Hassler et al., 2014), and the radiation data collected by RAD on the surface of Mars will inform projections of crew health risks and the design of protective surface habitats and other countermeasures for future human missions in the coming decades.

[Anthropogenic sources of radiation hazard in the near-Earth space].

PubMed

Fedoseev, G A

2004-01-01

All plausible artificial radioactive sources entering the near-Earth space (NES) were systematized and consequences of various large radiation accidents and catastrophes to Earth and NES were analyzed. Aggressive "population" of near-Earth orbits by space stations with rotating crews, unmanned research platforms and observatories extends "borderlines" of the noosphere raising at the same time concerns about the noosphere radiation safety and global radioecology. Specifically, consideration is given to the facts of negative effects of space power reactor facilities on results of orbital astrophysical investigations.

Assessing noise sources at synchrotron infrared ports

PubMed Central

Lerch, Ph.; Dumas, P.; Schilcher, T.; Nadji, A.; Luedeke, A.; Hubert, N.; Cassinari, L.; Boege, M.; Denard, J.-C.; Stingelin, L.; Nadolski, L.; Garvey, T.; Albert, S.; Gough, Ch.; Quack, M.; Wambach, J.; Dehler, M.; Filhol, J.-M.

2012-01-01

Today, the vast majority of electron storage rings delivering synchrotron radiation for general user operation offer a dedicated infrared port. There is growing interest expressed by various scientific communities to exploit the mid-IR emission in microspectroscopy, as well as the far infrared (also called THz) range for spectroscopy. Compared with a thermal (laboratory-based source), IR synchrotron radiation sources offer enhanced brilliance of about two to three orders of magnitude in the mid-IR energy range, and enhanced flux and brilliance in the far-IR energy range. Synchrotron radiation also has a unique combination of a broad wavelength band together with a well defined time structure. Thermal sources (globar, mercury filament) have excellent stability. Because the sampling rate of a typical IR Fourier-transform spectroscopy experiment is in the kHz range (depending on the bandwidth of the detector), instabilities of various origins present in synchrotron radiation sources play a crucial role. Noise recordings at two different IR ports located at the Swiss Light Source and SOLEIL (France), under conditions relevant to real experiments, are discussed. The lowest electron beam fluctuations detectable in IR spectra have been quantified and are shown to be much smaller than what is routinely recorded by beam-position monitors. PMID:22186638

Secondary standards laboratories for ionizing radiation calibrations: The national laboratory interests

NASA Astrophysics Data System (ADS)

Roberson, P. I.; Campbell, G. W.

1984-11-01

The national laboratories are probable candidates to serve as secondary standards laboratories for the federal sector. Representatives of the major Department of Energy laboratories were polled concerning attitudes toward a secondary laboratory structure. Generally, the need for secondary laboratories was recognized and the development of such a program was encouraged. The secondary laboratories should be reviewed and inspected by the National Bureau of Standards. They should offer all of the essential, and preferably additional, calibration services in the field of radiological health protection. The selection of secondary laboratories should be based on economic and geographic criteria and/or be voluntary.

The uses of synchrotron radiation sources for elemental and chemical microanalysis

USGS Publications Warehouse

Chen, J.R.; Chao, E.C.T.; Minkin, J.A.; Back, J.M.; Jones, K.W.; Rivers, M.L.; Sutton, S.R.

1990-01-01

Synchrotron radiation sources offer important features for the analysis of a material. Among these features is the ability to determine both the elemental composition of the material and the chemical state of its elements. For microscopic analysis synchrotron X-ray fluorescence (SXRF) microprobes now offer spatial resolutions of 10 ??m with minimum detection limits in the 1-10 ppm range depending on the nature of the sample and the synchrotron source used. This paper describes the properties of synchrotron radiation and their importance for elemental analysis, existing synchrotron facilities and those under construction that are optimum for SXRF microanalysis, and a number of applications including the high energy excitation of the K lines of heavy elements, microtomography, and XANES and EXAFS spectroscopies. ?? 1990.

What views and uses of radiation sources in the 21st century?

PubMed

Blix, H

2001-04-01

Considering that in 1899 neither biotechnology nor the electronic revolution were foreseen, some humility might be advisable when one looks into the crystal ball for the future role of radiation sources. In the past 50 years, nuclear medicine, nuclear weapons, and nuclear power have had a huge impact in the world. In the next 50 years, nuclear weapons may be phased out, nuclear power revived, and nuclear medicine may continue, especially for diagnostic purposes. Conflicts between great powers and blocks will no longer be about territorial or ideological domination but about trade, finance, information, and the environment and the weapons used will not be bombs but investments, credits, and control of information. Nuclear power-still based on fission-will be relaunched and get more uses, e.g., to propel ships, to produce heat for industry and for space heating, and perhaps to desalinate water. The public will be more at ease with radiation as it is better educated, as nuclear safety continuously improves and new types of nuclear power plants emerge, as waste sites fail to cause any problems, and as no other energy source is found to deliver so much energy at reasonable cost with negligible impact on climate and environment. One kilogram of oil corresponds to 4 kWh of electricity. One kilogram of uranium fuel corresponds to 50,000 kWh, and 1 kg of plutonium 6,000,000 kWh! In nuclear medicine, radiation may give way to other treatments as the understanding of cancer advances. On the other hand, the extreme ease with which sources of radiation can be identified is unmatched and likely to make them useful tools as tracers and markers in medicine-and other fields-for a long time. For certain uses--perhaps food irradiation--radiation sources, such as cobalt, may be replaced by accelerators which may be switched on and off at will. As more sources are used, registration and control of them must be made very effective around the whole world. Very high natural emissions of

X-ray intensity and source size characterizations for the 25 kV upgraded Manson source at Sandia National Laboratories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loisel, G., E-mail: gploise@sandia.gov; Lake, P.; Gard, P.

2016-11-15

At Sandia National Laboratories, the x-ray generator Manson source model 5 was upgraded from 10 to 25 kV. The purpose of the upgrade is to drive higher characteristics photon energies with higher throughput. In this work we present characterization studies for the source size and the x-ray intensity when varying the source voltage for a series of K-, L-, and M-shell lines emitted from Al, Y, and Au elements composing the anode. We used a 2-pinhole camera to measure the source size and an energy dispersive detector to monitor the spectral content and intensity of the x-ray source. As themore » voltage increases, the source size is significantly reduced and line intensity is increased for the three materials. We can take advantage of the smaller source size and higher source throughput to effectively calibrate the suite of Z Pulsed Power Facility crystal spectrometers.« less

6th International Conference on Biophysics & Synchrotron Radiation. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moffat, Keith

1999-08-03

The 6th International Conference on Biophysics and Synchrotron Rdiation was held at the Advanced Photon Source, Argonne National Laboratory, from August 4-8, 1998, with pre-conference activities on August 3. Over 300 attendees and 65 presenters participated in the conference that was collaboratively hosted by the University of Chicago, Center for Advanced Radiation Sources and the Advanced Photon Source.

Laboratory simulation of interplanetary ultraviolet radiation (broad spectrum) and its effects on Deinococcus radiodurans

NASA Astrophysics Data System (ADS)

Paulino-Lima, Ivan Gláucio; Pilling, Sérgio; Janot-Pacheco, Eduardo; de Brito, Arnaldo Naves; Barbosa, João Alexandre Ribeiro Gonçalves; Leitão, Alvaro Costa; Lage, Claudia de Alencar Santos

2010-08-01

The radiation-resistant bacterium Deinococcus radiodurans was exposed to a simulated interplanetary UV radiation at the Brazilian Synchrotron Light Laboratory (LNLS). Bacterial samples were irradiated on different substrates to investigate the influence of surface relief on cell survival. The effects of cell multi-layers were also investigated. The ratio of viable microorganisms remained virtually the same (average 2%) for integrated doses from 1.2 to 12 kJ m -2, corresponding to 16 h of irradiation at most. The asymptotic profiles of the curves, clearly connected to a shielding effect provided by multi-layering cells on a cavitary substrate (carbon tape), means that the inactivation rate may not change significantly along extended periods of exposure to radiation. Such high survival rates reinforce the possibility of an interplanetary transfer of viable microbes.

Radiation force on absorbing targets and power measurements of a high intensity focused ultrasound (HIFU) source

NASA Astrophysics Data System (ADS)

Qian, Zuwen; Zhu, Zhemin; Ye, Shigong; Jiang, Wenhua; Zhu, Houqing; Yu, Jinshen

2010-10-01

Based on the analytic expressions for the radiated field of a circular concave piston given by Hasegawa et al., an integral for calculation of the radiation force on a plane absorbing target in a spherically focused field is derived. A general relation between acoustic power P and normal radiation force F n is obtained under the condition of kr ≫ 1. Numerical computation is carried out by using the symbolic computation program for practically focused sources and absorbing circular targets. The results show that, for a given source, there is a range of target positions where the radiation force is independent of the target’s position under the assumption that the contribution of the acoustic field behind the target to the radiation force can be neglected. The experiments are carried out and confirm that there is a range of target positions where the measured radiation force is basically independent of the target’s position even at high acoustic power (up to 700 W). It is believed that when the radiation force method is used to measure the acoustic power radiated from a focused source, the size of the target must be selected in such a way that no observable sound can be found in the region behind the target.

New blackbody calibration source for low temperatures from -20 C to +350 C

NASA Astrophysics Data System (ADS)

Mester, Ulrich; Winter, Peter

2001-03-01

Calibration procedures for infrared thermometers and thermal imaging systems require radiation sources of precisely known radiation properties. In the physical absence of an ideal Planck's radiator, the German Committee VDI/VDE-GMA FA 2.51, 'Applied Radiation Thermometry', agreed upon desirable specifications and limiting parameters for a blackbody calibration source with a temperature range from -20 degree(s)C to +350 degree(s)C, a spectral range from 2 to 15 microns, an emissivity greater than 0.999 and a useful source aperture of 60 mm, among others. As a result of the subsequent design and development performed with the support of the laboratory '7.31 Thermometry' of the German national institute of natural and engineering sciences (PTB), the Mester ME20 Blackbody Calibration Source is presented. The ME20 meets or exceeds all of the specifications formulated by the VDI/VDE committee.

Light-absorbing carbon from prescribed and laboratory biomass burning and gasoline vehicle emissions

EPA Science Inventory

Carbonaceous aerosols are ubiquitous in the atmosphere and can directly affect Earth’s climate by absorbing and scattering incoming solar radiation. Both field and laboratory measurements have confirmed that biomass burning (BB) is an important primary source of light absorbing o...

A biotechnological project with a gamma radiation source of 100,000 Ci

NASA Astrophysics Data System (ADS)

Lombardo, J. H.; Smolko, E. E.

A project for the production of radiovaccines and other bio-medical products is presented which includes a radiation facility provided with a gamma ray source equivalent to 100,000 Ci of Co-60. The whole process incorporates novel basic features in virus production and inactivation steps. The former is carried out in animals previously subjected to immunodepression through electromagnetic radiation. The later is obtained at low temperatures by using either electromagnetic or particle radiations. A vaccine manufacture process is shown to illustrate the utilization of ionizing radiations to obtain a foot and mouth disease virus (FMDV) vaccine with good antigenic quality and low cost.

Results of Research on Overcoming Pulse Shortening of GW Class HPM Sources

DTIC Science & Technology

1997-05-29

The RPM sources basic research program of the Air Force has a major emphasis on the pulse shortening problem. This includes collaborative work in...universities and the Phillips Laboratory . We have demonstrated two fundamentally different RPM sources which radiate rf power in excess of 1 GW and are

THz and Sub-THz Capabilities of a Table-Top Radiation Source Driven by an RF Thermionic Electron Gun

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smirnov, Alexei V.; Agustsson, R.; Boucher, S.

Design features and experimental results are presented for a sub-mm wave source [1] based on APS RF thermionic electron gun. The setup includes compact alpha-magnet, quadrupoles, sub-mm-wave radiators, and THz optics. The sub-THz radiator is a planar, oversized structure with gratings. Source upgrade for generation frequencies above 1 THz is discussed. The THz radiator will use a short-period undulator having 1 T field amplitude, ~20 cm length, and integrated with a low-loss oversized waveguide. Both radiators are integrated with a miniature horn antenna and a small ~90°-degree in-vacuum bending magnet. The electron beamline is designed to operate different modes includingmore » conversion to a flat beam interacting efficiently with the radiator. The source can be used for cancer diagnostics, surface defectoscopy, and non-destructive testing. Sub-THz experiment demonstrated a good potential of a robust, table-top system for generation of a narrow bandwidth THz radiation. This setup can be considered as a prototype of a compact, laser-free, flexible source capable of generation of long trains of Sub-THz and THz pulses with repetition rates not available with laser-driven sources.« less

Practical biosafety in the tuberculosis laboratory: containment at the source is what truly counts.

PubMed

van Soolingen, D; Wisselink, H J; Lumb, R; Anthony, R; van der Zanden, A; Gilpin, C

2014-08-01

In industrialised countries, sufficient resources for establishing and maintaining fully equipped biosafety level 3 (BSL-3) laboratories according to international standards are generally available. BSL-3 laboratories are designed to provide several layers of containment to protect the laboratory worker as well as the outside environment and community from risk of exposure in case of local contamination. However, such facilities are scarce in high-burden settings, primarily due to the high financial burden and complexity of the initial construction and/or regular maintenance. Measures to prevent unintended exposure to Mycobacterium tuberculosis during laboratory manipulation of specimens and cultures is the first, and by far the most important, aspect of containment. This paper focuses on the need for risk containment at source. Assuming that in many settings the establishment of BSL-3 laboratories with all the required features is not achievable, this paper also discusses the minimum requirements necessary to mitigate risks associated with particular laboratory procedures. The term 'TB containment laboratory' is used throughout this paper to describe the minimum requirements for a laboratory suitable for high-risk procedures. The TB containment laboratory has many, but not all, of the features of a BSL-3 laboratory.

10 CFR 34.21 - Limits on external radiation levels from storage containers and source changers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Limits on external radiation levels from storage... INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.21 Limits on external radiation levels from storage containers and source changers. The maximum...

10 CFR 34.21 - Limits on external radiation levels from storage containers and source changers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Limits on external radiation levels from storage... INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.21 Limits on external radiation levels from storage containers and source changers. The maximum...

10 CFR 34.21 - Limits on external radiation levels from storage containers and source changers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Limits on external radiation levels from storage... INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.21 Limits on external radiation levels from storage containers and source changers. The maximum...

10 CFR 34.21 - Limits on external radiation levels from storage containers and source changers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Limits on external radiation levels from storage... INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.21 Limits on external radiation levels from storage containers and source changers. The maximum...

10 CFR 34.21 - Limits on external radiation levels from storage containers and source changers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Limits on external radiation levels from storage... INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.21 Limits on external radiation levels from storage containers and source changers. The maximum...

Radiative Transfer Theory Verified by Controlled Laboratory Experiments

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.; Goldstein, Dennis H.; Chowdhary, Jacek; Lompado, Arthur

2013-01-01

We report the results of high-accuracy controlled laboratory measurements of the Stokes reflection matrix for suspensions of submicrometer-sized latex particles in water and compare them with the results of a numerically exact computer solution of the vector radiative transfer equation (VRTE). The quantitative performance of the VRTE is monitored by increasing the volume packing density of the latex particles from 2 to 10. Our results indicate that the VRTE can be applied safely to random particulate media with packing densities up to 2. VRTE results for packing densities of the order of 5 should be taken with caution, whereas the polarized bidirectional reflectivity of suspensions with larger packing densities cannot be accurately predicted. We demonstrate that a simple modification of the phase matrix entering the VRTE based on the so-called static structure factor can be a promising remedy that deserves further examination.

Report: EPA’s Radiation and Indoor Environments National Laboratory Should Improve Its Computer Room Security Controls

EPA Pesticide Factsheets

Report #12-P-0847, September 21, 2012.Our review of the security posture and in-place environmental controls of EPA’s Radiation and Indoor Environments National Laboratory computer room disclosed an array of security and environmental control deficiencies.

Debris- and radiation-induced damage effects on EUV nanolithography source collector mirror optics performance

NASA Astrophysics Data System (ADS)

Allain, J. P.; Nieto, M.; Hendricks, M.; Harilal, S. S.; Hassanein, A.

2007-05-01

Exposure of collector mirrors facing the hot, dense pinch plasma in plasma-based EUV light sources to debris (fast ions, neutrals, off-band radiation, droplets) remains one of the highest critical issues of source component lifetime and commercial feasibility of nanolithography at 13.5-nm. Typical radiators used at 13.5-nm include Xe and Sn. Fast particles emerging from the pinch region of the lamp are known to induce serious damage to nearby collector mirrors. Candidate collector configurations include either multi-layer mirrors (MLM) or single-layer mirrors (SLM) used at grazing incidence. Studies at Argonne have focused on understanding the underlying mechanisms that hinder collector mirror performance at 13.5-nm under fast Sn or Xe exposure. This is possible by a new state-of-the-art in-situ EUV reflectometry system that measures real time relative EUV reflectivity (15-degree incidence and 13.5-nm) variation during fast particle exposure. Intense EUV light and off-band radiation is also known to contribute to mirror damage. For example offband radiation can couple to the mirror and induce heating affecting the mirror's surface properties. In addition, intense EUV light can partially photo-ionize background gas (e.g., Ar or He) used for mitigation in the source device. This can lead to local weakly ionized plasma creating a sheath and accelerating charged gas particles to the mirror surface and inducing sputtering. In this paper we study several aspects of debris and radiation-induced damage to candidate EUVL source collector optics materials. The first study concerns the use of IMD simulations to study the effect of surface roughness on EUV reflectivity. The second studies the effect of fast particles on MLM reflectivity at 13.5-nm. And lastly the third studies the effect of multiple energetic sources with thermal Sn on 13.5-nm reflectivity. These studies focus on conditions that simulate the EUVL source environment in a controlled way.

International Collaboration for Galactic Cosmic Ray Simulation at the NASA Space Radiation Laboratory

NASA Technical Reports Server (NTRS)

Norbury, John W.; Slaba, Tony C.; Rusek, Adam; Durante, Marco; Reitz, Guenther

2015-01-01

An international collaboration on Galactic Cosmic Ray (GCR) simulation is being formed to make recommendations on how to best simulate the GCR spectrum at ground based accelerators. The external GCR spectrum is significantly modified when it passes through spacecraft shielding and astronauts. One approach for simulating the GCR space radiation environment at ground based accelerators would use the modified spectrum, rather than the external spectrum, in the accelerator beams impinging on biological targets. Two recent workshops have studied such GCR simulation. The first workshop was held at NASA Langley Research Center in October 2014. The second workshop was held at the NASA Space Radiation Investigators' workshop in Galveston, Texas in January 2015. The anticipated outcome of these and other studies may be a report or journal article, written by an international collaboration, making accelerator beam recommendations for GCR simulation. This poster describes the status of GCR simulation at the NASA Space Radiation Laboratory and encourages others to join the collaboration.

On the source location of radiation belt relativistic electrons

NASA Astrophysics Data System (ADS)

Selesnick, R. S.; Blake, J. B.

2000-02-01

Observations from the High Sensitivity Telescope (HIST) on Polar made around Janurary and May 1998 are used to constrain the source location of outer radiation belt relativistic electrons. Phase space densities calculated as a function of the three adiabatic invariants show positive radial gradients for L<4, suggestive of no source in that region. In particular, the peak intensity near L=3 of a large enhancement beginning on May 4, 1998, appears to have been formed by inward transport over a period of several days. For L>4, peaks in the radial dependence of the phase space density are suggestive of a local electron source that may be nonadiabatic acceleration or pitch angle scattering. However, discrepancies in the results obtained with different magnetic field models and at different local times make this a tentative conclusion.

Radiation Source Mapping with Bayesian Inverse Methods

DOE PAGES

Hykes, Joshua M.; Azmy, Yousry Y.

2017-03-22

In this work, we present a method to map the spectral and spatial distributions of radioactive sources using a limited number of detectors. Locating and identifying radioactive materials is important for border monitoring, in accounting for special nuclear material in processing facilities, and in cleanup operations following a radioactive material spill. Most methods to analyze these types of problems make restrictive assumptions about the distribution of the source. In contrast, the source mapping method presented here allows an arbitrary three-dimensional distribution in space and a gamma peak distribution in energy. To apply the method, the problem is cast as anmore » inverse problem where the system’s geometry and material composition are known and fixed, while the radiation source distribution is sought. A probabilistic Bayesian approach is used to solve the resulting inverse problem since the system of equations is ill-posed. The posterior is maximized with a Newton optimization method. The probabilistic approach also provides estimates of the confidence in the final source map prediction. A set of adjoint, discrete ordinates flux solutions, obtained in this work by the Denovo code, is required to efficiently compute detector responses from a candidate source distribution. These adjoint fluxes form the linear mapping from the state space to the response space. The test of the method’s success is simultaneously locating a set of 137Cs and 60Co gamma sources in a room. This test problem is solved using experimental measurements that we collected for this purpose. Because of the weak sources available for use in the experiment, some of the expected photopeaks were not distinguishable from the Compton continuum. However, by supplanting 14 flawed measurements (out of a total of 69) with synthetic responses computed by MCNP, the proof-of-principle source mapping was successful. The locations of the sources were predicted within 25 cm for two of the sources

GARLIC, A SHIELDING PROGRAM FOR GAMMA RADIATION FROM LINE- AND CYLINDER- SOURCES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roos, M.

1959-06-01

GARLlC is a program for computing the gamma ray flux or dose rate at a shielded isotropic point detector, due to a line source or the line equivalent of a cylindrical source. The source strength distribution along the line must be either uniform or an arbitrary part of the positive half-cycle of a cosine function The line source can be orierted arbitrarily with respect to the main shield and the detector, except that the detector must not be located on the line source or on its extensionThe main source is a homogeneous plane slab in which scattered radiation is accountedmore » for by multiplying each point element of the line source by a point source buildup factor inside the integral over the point elements. Between the main shield and the line source additional shields can be introduced, which are either plane slabs, parallel to the main shield, or cylindrical rings, coaxial with the line source. Scattered radiation in the additional shields can only be accounted for by constant build-up factors outside the integral. GARLlC-xyz is an extended version particularly suited for the frequently met problem of shielding a room containing a large number of line sources in diHerent positions. The program computes the angles and linear dimensions of a problem for GARLIC when the positions of the detector point and the end points of the line source are given as points in an arbitrary rectangular coordinate system. As an example the isodose curves in water are presented for a monoenergetic cosine-distributed line source at several source energies and for an operating fuel element of the Swedish reactor R3, (auth)« less

Ultraviolet out-of-band radiation studies in laser tin plasma sources

NASA Astrophysics Data System (ADS)

Parchamy, Homaira; Szilagyi, John; Masnavi, Majid; Richardson, Martin

2017-11-01

Out-of-band long wavelength emission measurements from high power, high-repetition-rate extreme-ultra-violet lithography (EUVL) laser plasma sources are imperative to estimating heat deposition in EUV mirrors, and the impact of short wavelength light transported through the imaging system to the wafer surface. This paper reports a series of experiments conducted to measure the absolute spectral irradiances of laser-plasmas produced from planar tin targets over the wavelength region of 124 to 164 nm by 1.06 μm wavelength, 10 ns full-width-at-half-maximum Gaussian laser pulses. The use of spherical targets is relevant to the EUVL source scenario. Although plasmas produced from planar surfaces evolve differently, there is a close similarity to the evolution of current from 10.6 μm CO2 laser EUVL sources, which use a pre-pulse from a lower energy solid-state laser to melt and reform an initial spherical droplet into a thin planar disc target. The maximum of radiation conversion efficiency in the 124-164 nm wavelength band (1%/2πsr) occurs at the laser intensity of 1010 W cm-2. A developed collisional-radiative model reveals the strong experimental spectra that originate mainly from the 4d105p2-4d105s5p, 4d105p-4d105s resonance lines, and 4d95p-4d95s unresolved transition arrays from Sn III, Sn IV, and Sn V ions, respectively. The calculated conversion efficiencies using a 2D radiation-hydrodynamics model are in agreement with the measurements. The model predicts the out-of-band (100-400 nm) radiation conversion efficiencies generated by both 1.06 and 10.6 μm pulses. The 10.6 μm laser pulse produces a higher conversion efficiency (12%/2πsr) at the lower laser intensity of 109 W cm-2.

Thermal Radiation Source Test Facility, Kirtland Air Force Base, New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, W.F.

This report describes the Thermal Radiation Source (TRS) Test Facility at Kirtland AF Base, New Mexico. It lists the instrumentation and equipment available for use by DOD and other government agencies studying the effects produced by nuclear weapons.

Understanding and Minimising Occupational Radiation in the Catheterisation Laboratory with PISAX and the ACIST CVi® Contrast Delivery System

PubMed Central

Bar, Olivier

2013-01-01

This paper provides an overview of radiation exposure and its associated risks in the cardiac catheterisation laboratory (cath lab), as well as strategies to minimise radiation exposure for operators, cath lab staff and patients. The benefits of using a mobile 2 mm lead equivalent radiation shield (PISAX) and adoption of an automated contrast injection system (the ACIST CVi® Contrast Delivery System) are discussed, and the potential advantages of their combination are reviewed. PMID:29588748

Development of the front end test stand and vessel for extraction and source plasma analyses negative hydrogen ion sources at the Rutherford Appleton Laboratory.

PubMed

Lawrie, S R; Faircloth, D C; Letchford, A P; Perkins, M; Whitehead, M O; Wood, T; Gabor, C; Back, J

2014-02-01

The ISIS pulsed spallation neutron and muon facility at the Rutherford Appleton Laboratory (RAL) in the UK uses a Penning surface plasma negative hydrogen ion source. Upgrade options for the ISIS accelerator system demand a higher current, lower emittance beam with longer pulse lengths from the injector. The Front End Test Stand is being constructed at RAL to meet the upgrade requirements using a modified ISIS ion source. A new 10% duty cycle 25 kV pulsed extraction power supply has been commissioned and the first meter of 3 MeV radio frequency quadrupole has been delivered. Simultaneously, a Vessel for Extraction and Source Plasma Analyses is under construction in a new laboratory at RAL. The detailed measurements of the plasma and extracted beam characteristics will allow a radical overhaul of the transport optics, potentially yielding a simpler source configuration with greater output and lifetime.

Estimation of neutron dose equivalent at the mezzanine of the Advanced Light Source and the laboratory boundary using the ORNL program MORSE.

PubMed

Sun, R K

1990-12-01

To investigate the radiation effect of neutrons near the Advanced Light Source (ALS) at Lawrence Berkeley Laboratory (LBL) with respect to the neutron dose equivalents in nearby occupied areas and at the site boundary, the neutron transport code MORSE, from Oak Ridge National Laboratory (ORNL), was used. These dose equivalents result from both skyshine neutrons transported by air scattering and direct neutrons penetrating the shielding. The ALS neutron sources are a 50-MeV linear accelerator and its transfer line, a 1.5-GeV booster, a beam extraction line, and a 1.9-GeV storage ring. The most conservative total occupational-dose-equivalent rate in the center of the ALS mezzanine, 39 m from the ALS center, was found to be 1.14 X 10(-3) Sv y-1 per 2000-h "occupational" year, and the total environmental-dose-equivalent rate at the ALS boundary, 125 m from the ALS center, was found to be 3.02 X 10(-4) Sv y-1 per 8760-h calendar year. More realistic dose-equivalent rates, using the nominal (expected) storage-ring current, were calculated to be 1.0 X 10(-4) Sv y-1 and 2.65 X 10(-5) Sv y-1 occupational year and calendar year, respectively, which are much lower than the DOE reporting levels.

[UV-radiation--sources, wavelength, environment].

PubMed

Hölzle, Erhard; Hönigsmann, Herbert

2005-09-01

The UV-radiation in our environment is part of the electromagnetic radiation, which emanates from the sun. It is designated as optical radiation and reaches from 290-4,000 nm on the earth's surface. According to international definitions UV irradiation is divided into short-wave UVC (200-280 nm), medium-wave UVB (280-320 nm), and long-wave UVA (320-400 nm). Solar radiation which reaches the surface of the globe at a defined geographical site and a defined time point is called global radiation. It is modified quantitatively and qualitatively while penetrating the atmosphere. Besides atmospheric conditions, like ozone layer and air pollution, geographic latitude, elevation, time of the season, time of the day, cloudiness and the influence of indirect radiation resulting from stray effects in the atmosphere and reflection from the underground play a role in modifying global radiation, which finally represents the biologically effective radiation. The radiation's distribution on the body surface varies according to sun angle and body posture. The cumulative UV exposure is mainly influenced by outdoor profession and recreational activities. The use of sun beds and phototherapeutic measures additionally may contribute to the cumulative UV dose.

Radiation exposure of the US population from consumer products and miscellaneous sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1987-12-30

The primary goal of the effort that resulted in this report was to update the earlier report issued by the NCRP on this subject (NCRP, 1977). In so doing, the Council has identified additional consumer products that can be sources of ionizing radiation, and has deleted coverage of some products that are either no longer available or whose use has essentially been discontinued. For each source category, a major effort has been made to provide data on the number of products currently in use, the rate at which such usage is changing, and the range of typical dose equivalents beingmore » received from that source by the general public. To the extent possible, an attempt has been made to provide information to assist in making decisions on whether a given application might better be replaced by some other method of accomplishing the same task without involving radiation exposure to the population. 162 refs., 2 figs., 23 tabs.« less

Radiation characteristics of a source in a thin substrate mounted over a dielectric medium

NASA Technical Reports Server (NTRS)

Engheta, Nader; Elachi, Charles

1988-01-01

The radiation pattern of a line source is calculated for the case in which the source is lying on the top or the bottom surface of a lossless dielectric substrate that is mounted on the top of semiinfinite dielectric medium. It is found that in both cases the pattern along the interfaces has a null; that the pattern in the upper semiinfinite medium has a single lobe; and that the pattern in the lower semiinfinite medium has many lobes, the number of which varies with the substrate thickness. In both cases, the power radiated into the lower medium is more than that radiated into the upper medium. Applications of this calculation to remote sensing, microstrip antenna technology, and antenna arrays are discussed.

[Experience of the development special medical technical laboratory for studies of effects caused by potent electromagnetic radiation in biologic objects].

PubMed

Gorodetsky, B N; Kalyada, T V; Petrov, S V

2015-01-01

This article covers topics of creating special medical technical laboratory for medial and biologic studies concerning influence of potent high-frequency elecromagnetic radiation on various biologic objects. The authors gave example of such laboratory, described its construction features, purpose and main characteristics of the included devices.

ERLN Radiation Focus Area

EPA Pesticide Factsheets

As part of the Environmental Response Laboratory Network, the National Air and Radiation Environmental Laboratory (NAREL) here provides your laboratory with access to radiation-specific laboratory guidance documents and training courses.

Correlation of radiation dose and heart rate in dual-source computed tomography coronary angiography.

PubMed

Laspas, Fotios; Tsantioti, Dimitra; Roussakis, Arkadios; Kritikos, Nikolaos; Efthimiadou, Roxani; Kehagias, Dimitrios; Andreou, John

2011-04-01

Computed tomography coronary angiography (CTCA) has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but the relatively high radiation dose remains a major concern. To evaluate the relationship between radiation exposure and heart rate (HR), in dual-source CTCA. Data from 218 CTCA examinations, performed with a dual-source 64-slices scanner, were statistically evaluated. Effective radiation dose, expressed in mSv, was calculated as the product of the dose-length product (DLP) times a conversion coefficient for the chest (mSv = DLPx0.017). Heart rate range and mean heart rate, expressed in beats per minute (bpm) of each individual during CTCA, were also provided by the system. Statistical analysis of effective dose and heart rate data was performed by using Pearson correlation coefficient and two-sample t-test. Mean HR and effective dose were found to have a borderline positive relationship. Individuals with a mean HR >65 bpm observed to receive a statistically significant higher effective dose as compared to those with a mean HR ≤65 bpm. Moreover, a strong correlation between effective dose and variability of HR of more than 20 bpm was observed. Dual-source CT scanners are considered to have the capability to provide diagnostic examinations even with high HR and arrhythmias. However, it is desirable to keep the mean heart rate below 65 bpm and heart rate fluctuation less than 20 bpm in order to reduce the radiation exposure.

Main sources of errors in diagnosis of chronic radiation sickness (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soldatova, V.A.

1973-11-01

With the aim of finding out the main sources of errors in the diagnosis of chronic radiation sickness, the author analyzed a total of 500 cases of this sickness in roenigenologists and radiologists sent to the clinic to be examined according to occupational indications. lt was shown that the main source of errors when interpreting the observed deviations as occupational was underestimation of etiological significance of functional and organic diseases of the nervous system, endocrinevascular dystonia and also such diseases as hypochromic anemia and chronic infection. The majority of diagnostic errors is explained by insufficient knowledge of the main regularitymore » of forming the picture of chronic radiation sickness and by the absence of the necessary differential diagnosis with general somatic diseases. (auth)« less

Results of neutron irradiation of GEM detector for plasma radiation detection

NASA Astrophysics Data System (ADS)

Jednorog, S.; Bienkowska, B.; Chernyshova, M.; Łaszynska, E.; Prokopowicz, R.; Ziołkowski, A.

2015-09-01

The detecting devices dedicated for plasma monitoring will be exposed for massive fluxes of neutron, photons as well as other rays that are components of fusion reactions and their product interactions with plasma itself or surroundings. In result detecting module metallic components will be activated becoming a source of radiation. Moreover, electronics components could change their electronic properties. The prototype GEM detector constructed for monitoring soft X-ray radiation in ITER oriented tokamaks was used for plasma monitoring during experimental campaign on tokamak ASDEX Upgrade. After that it became a source of gamma radiation caused by neutrons. The present work contains description of detector activation in the laboratory conditions.

Comparison of Martian Surface Radiation Predictions to the Measurements of Mars Science Laboratory Radiation Assessment Detector (MSL/RAD)

NASA Technical Reports Server (NTRS)

Kim, Myung-Hee Y.; Cucinotta, Francis A.; Zeitlin, Cary; Hassler, Donald M.; Ehresmann, Bent; Rafkin, Scot C. R.; Wimmer-Schweingruber, Robert F; Boettcher, Stephan; Boehm, Eckart; Guo, Jingnan;

Sources of Differences in On-Orbit Total Solar Irradiance Measurements and Description of Proposed Laboratory Intercomparison

NASA Technical Reports Server (NTRS)

Butler, J.J.; Johnson, B. C.; Rice, J. P.; Shirley, E. L.; Barnes, R.A.

2008-01-01

There is a 5 W/sq m (about 0.35 %) difference between current on-orbit Total Solar Irradiance (TSI) measurements. On 18-20 July 2005, a workshop was held at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland that focused on understanding possible reasons for this difference, through an examination of the instrument designs, calibration approaches, and appropriate measurement equations. The instruments studied in that workshop included the Active Cavity Radiometer Irradiance Monitor III (ACRIM III) on the Active Cavity Radiometer Irradiance Monitor SATellite (ACRIMSAT), the Total Irradiance Monitor (TIM) on the Solar Radiation and Climate Experiment (SORCE), the Variability of solar IRradiance and Gravity Oscillations (VIRGO) on the Solar and Heliospheric Observatory (SOHO), and the Earth Radiation Budget Experiment (ERBE) on the Earth Radiation Budget Satellite (ERBS). Presentations for each instrument included descriptions of its design, its measurement equation and uncertainty budget, and the methods used to assess on-orbit degradation. The workshop also included a session on satellite- and ground-based instrument comparisons and a session on laboratory-based comparisons and the application of new laboratory comparison techniques. The workshop has led to investigations of the effects of diffraction and of aperture area measurements on the differences between instruments. In addition, a laboratory-based instrument comparison is proposed that uses optical power measurements (with lasers that underEll the apertures of the TSI instruments), irradiance measurements (with lasers that overfill the apertures of the TSI instrument), and a cryogenic electrical substitution radiometer as a standard for comparing the instruments. A summary of the workshop and an overview of the proposed research efforts are presented here.

Performance of light sources and radiation sensors under low gravity realized by parabolic airplane flights

NASA Astrophysics Data System (ADS)

Hirai, Hiroaki; Kitaya, Yoshiaki; Hirai, Takehiro

A fundamental study was conducted to establish an experimental system for space farming. Since to ensure optimal light for plant cultivation in space is of grave importance, this study examined the performance of light sources and radiation sensors under microgravity conditions created during the parabolic airplane flight. Three kinds of light sources, a halogen bulb, a fluorescent tube, and blue and red LEDs, and ten models of radiation sensors available in the market were used for the experiment. Surface temperature of the light sources, output signals from the radiation sensors, spectroscopic characteristics were measured at the gravity levels of 0.01, 1.0 and 1.8 G for 20 seconds each during parabolic airplane flights. As a result, the performance of the halogen lamp was affected the most by the gravity level among the three light sources. Under the microgravity conditions which do not raise heat convection, the temperature of the halogen lamp rose and the output of the radiation sensors increased. Spectral distributions of the halogen lamp indicated that peak wavelength appeared the highest at the level of 0.01G, which contributed to the increase in light intensity. In the case of red and blue LEDs, which are promising light sources in space farming, the temperature of both LED chips rose but irradiance from red LED increased and that from blue LED decreased under microgravity conditions due to the different thermal characteristics.

Nonuniformity correction of infrared cameras by reading radiance temperatures with a spatially nonhomogeneous radiation source

NASA Astrophysics Data System (ADS)

Gutschwager, Berndt; Hollandt, Jörg

2017-01-01

We present a novel method of nonuniformity correction (NUC) of infrared cameras and focal plane arrays (FPA) in a wide optical spectral range by reading radiance temperatures and by applying a radiation source with an unknown and spatially nonhomogeneous radiance temperature distribution. The benefit of this novel method is that it works with the display and the calculation of radiance temperatures, it can be applied to radiation sources of arbitrary spatial radiance temperature distribution, and it only requires sufficient temporal stability of this distribution during the measurement process. In contrast to this method, an initially presented method described the calculation of NUC correction with the reading of monitored radiance values. Both methods are based on the recording of several (at least three) images of a radiation source and a purposeful row- and line-shift of these sequent images in relation to the first primary image. The mathematical procedure is explained in detail. Its numerical verification with a source of a predefined nonhomogeneous radiance temperature distribution and a thermal imager of a predefined nonuniform FPA responsivity is presented.

Source attribution of black carbon and its direct radiative forcing in China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Yang; Wang, Hailong; Smith, Steven J.

The source attributions for mass concentration, haze formation, transport and direct radiative forcing of black carbon (BC) in various regions of China are quantified in this study using the Community Earth System Model (CESM) with a source-tagging technique. Anthropogenic emissions are from the Community Emissions Data System that is newly developed for the Coupled Model Intercomparison Project Phase 6 (CMIP6). Over north China where the air quality is often poor, about 90 % of near-surface BC concentration is contributed by local emissions. Overall, 35 % of BC concentration over south China in winter can be attributed to emissions from north China, andmore » 19 % comes from sources outside China in spring. For other regions in China, BC is largely contributed from nonlocal sources. We further investigated potential factors that contribute to the poor air quality in China. During polluted days, a net inflow of BC transported from nonlocal source regions associated with anomalous winds plays an important role in increasing local BC concentrations. BC-containing particles emitted from East Asia can also be transported across the Pacific. Our model results show that emissions from inside and outside China are equally important for the BC outflow from East Asia, while emissions from China account for 8 % of BC concentration and 29 % in column burden in the western United States in spring. Radiative forcing estimates show that 65 % of the annual mean BC direct radiative forcing (2.2 W m −2) in China results from local emissions, and the remaining 35 % is contributed by emissions outside of China. Efficiency analysis shows that a reduction in BC emissions over eastern China could have a greater benefit for the regional air quality in China, especially in the winter haze season.« less

Source attribution of black carbon and its direct radiative forcing in China

DOE PAGES

Yang, Yang; Wang, Hailong; Smith, Steven J.; ...

2017-03-30

The source attributions for mass concentration, haze formation, transport and direct radiative forcing of black carbon (BC) in various regions of China are quantified in this study using the Community Earth System Model (CESM) with a source-tagging technique. Anthropogenic emissions are from the Community Emissions Data System that is newly developed for the Coupled Model Intercomparison Project Phase 6 (CMIP6). Over north China where the air quality is often poor, about 90 % of near-surface BC concentration is contributed by local emissions. Overall, 35 % of BC concentration over south China in winter can be attributed to emissions from north China, andmore » 19 % comes from sources outside China in spring. For other regions in China, BC is largely contributed from nonlocal sources. We further investigated potential factors that contribute to the poor air quality in China. During polluted days, a net inflow of BC transported from nonlocal source regions associated with anomalous winds plays an important role in increasing local BC concentrations. BC-containing particles emitted from East Asia can also be transported across the Pacific. Our model results show that emissions from inside and outside China are equally important for the BC outflow from East Asia, while emissions from China account for 8 % of BC concentration and 29 % in column burden in the western United States in spring. Radiative forcing estimates show that 65 % of the annual mean BC direct radiative forcing (2.2 W m −2) in China results from local emissions, and the remaining 35 % is contributed by emissions outside of China. Efficiency analysis shows that a reduction in BC emissions over eastern China could have a greater benefit for the regional air quality in China, especially in the winter haze season.« less

Antenna radiation patterns in the whistler wave regime measured in a large laboratory plasma

NASA Technical Reports Server (NTRS)

Stenzel, R. L.

1976-01-01

Antenna radiation patterns of balanced electric dipoles and shielded magnetic loop antennas are obtained by measuring the relative wave amplitude with a small receiver antenna scanned around the exciter in a large uniform collisionless magnetized laboratory plasma in the whistler wave regime. The boundary effects are assumed to be negligible even for many farfield patterns. Characteristic differences are observed between electrically short and long antennas, the former exhibiting resonance cones and the latter showing dipole-like antenna patterns along the magnetic field. Resonance cones due to small electric dipoles and magnetic loops are observed in both the near zone and the far zone. A self-focusing process is revealed which produces a pencil-shaped field-aligned radiation pattern.

Equivalent radiation source of 3D package for electromagnetic characteristics analysis

NASA Astrophysics Data System (ADS)

Li, Jun; Wei, Xingchang; Shu, Yufei

2017-10-01

An equivalent radiation source method is proposed to characterize electromagnetic emission and interference of complex three dimensional integrated circuits (IC) in this paper. The method utilizes amplitude-only near-field scanning data to reconstruct an equivalent magnetic dipole array, and the differential evolution optimization algorithm is proposed to extract the locations, orientation and moments of those dipoles. By importing the equivalent dipoles model into a 3D full-wave simulator together with the victim circuit model, the electromagnetic interference issues in mixed RF/digital systems can be well predicted. A commercial IC is used to validate the accuracy and efficiency of this proposed method. The coupled power at the victim antenna port calculated by the equivalent radiation source is compared with the measured data. Good consistency is obtained which confirms the validity and efficiency of the method. Project supported by the National Nature Science Foundation of China (No. 61274110).

Review of Hybrid (Deterministic/Monte Carlo) Radiation Transport Methods, Codes, and Applications at Oak Ridge National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, John C; Peplow, Douglas E.; Mosher, Scott W

2011-01-01

This paper provides a review of the hybrid (Monte Carlo/deterministic) radiation transport methods and codes used at the Oak Ridge National Laboratory and examples of their application for increasing the efficiency of real-world, fixed-source Monte Carlo analyses. The two principal hybrid methods are (1) Consistent Adjoint Driven Importance Sampling (CADIS) for optimization of a localized detector (tally) region (e.g., flux, dose, or reaction rate at a particular location) and (2) Forward Weighted CADIS (FW-CADIS) for optimizing distributions (e.g., mesh tallies over all or part of the problem space) or multiple localized detector regions (e.g., simultaneous optimization of two or moremore » localized tally regions). The two methods have been implemented and automated in both the MAVRIC sequence of SCALE 6 and ADVANTG, a code that works with the MCNP code. As implemented, the methods utilize the results of approximate, fast-running 3-D discrete ordinates transport calculations (with the Denovo code) to generate consistent space- and energy-dependent source and transport (weight windows) biasing parameters. These methods and codes have been applied to many relevant and challenging problems, including calculations of PWR ex-core thermal detector response, dose rates throughout an entire PWR facility, site boundary dose from arrays of commercial spent fuel storage casks, radiation fields for criticality accident alarm system placement, and detector response for special nuclear material detection scenarios and nuclear well-logging tools. Substantial computational speed-ups, generally O(102-4), have been realized for all applications to date. This paper provides a brief review of the methods, their implementation, results of their application, and current development activities, as well as a considerable list of references for readers seeking more information about the methods and/or their applications.« less

Review of Hybrid (Deterministic/Monte Carlo) Radiation Transport Methods, Codes, and Applications at Oak Ridge National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, John C; Peplow, Douglas E.; Mosher, Scott W

2010-01-01

This paper provides a review of the hybrid (Monte Carlo/deterministic) radiation transport methods and codes used at the Oak Ridge National Laboratory and examples of their application for increasing the efficiency of real-world, fixed-source Monte Carlo analyses. The two principal hybrid methods are (1) Consistent Adjoint Driven Importance Sampling (CADIS) for optimization of a localized detector (tally) region (e.g., flux, dose, or reaction rate at a particular location) and (2) Forward Weighted CADIS (FW-CADIS) for optimizing distributions (e.g., mesh tallies over all or part of the problem space) or multiple localized detector regions (e.g., simultaneous optimization of two or moremore » localized tally regions). The two methods have been implemented and automated in both the MAVRIC sequence of SCALE 6 and ADVANTG, a code that works with the MCNP code. As implemented, the methods utilize the results of approximate, fast-running 3-D discrete ordinates transport calculations (with the Denovo code) to generate consistent space- and energy-dependent source and transport (weight windows) biasing parameters. These methods and codes have been applied to many relevant and challenging problems, including calculations of PWR ex-core thermal detector response, dose rates throughout an entire PWR facility, site boundary dose from arrays of commercial spent fuel storage casks, radiation fields for criticality accident alarm system placement, and detector response for special nuclear material detection scenarios and nuclear well-logging tools. Substantial computational speed-ups, generally O(10{sup 2-4}), have been realized for all applications to date. This paper provides a brief review of the methods, their implementation, results of their application, and current development activities, as well as a considerable list of references for readers seeking more information about the methods and/or their applications.« less

Multichannel extremely broadband near-IR radiation sources for optical coherence tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wojtkowski, M; Fujimoto, J G; Lapin, P I

The construction and output parameters of two experimental samples of near-IR radiation sources based on the superposition of radiation from several superluminescent diodes are described. The first, three-channel sample emitting 18 mW of cw output power in a spectral band of width 105 nm through a single-mode fibre, is optimised for ophthalmology coherence tomography. The second, four-channel sample emits the 870-nm band of width more than 200 nm, which corresponds to the record coherence length smaller than 4 {mu}m. (laser applications and other topics in quantum electronics)

Active control of sound radiation from a vibrating rectangular panel by sound sources and vibration inputs - An experimental comparison

NASA Technical Reports Server (NTRS)

Fuller, C. R.; Hansen, C. H.; Snyder, S. D.

1991-01-01

Active control of sound radiation from a rectangular panel by two different methods has been experimentally studied and compared. In the first method a single control force applied directly to the structure is used with a single error microphone located in the radiated acoustic field. Global attenuation of radiated sound was observed to occur by two main mechanisms. For 'on-resonance' excitation, the control force had the effect of increasing the total panel input impedance presented to the nosie source, thus reducing all radiated sound. For 'off-resonance' excitation, the control force tends not significantly to modify the panel total response amplitude but rather to restructure the relative phases of the modes leading to a more complex vibration pattern and a decrease in radiation efficiency. For acoustic control, the second method, the number of acoustic sources required for global reduction was seen to increase with panel modal order. The mechanism in this case was that the acoustic sources tended to create an inverse pressure distribution at the panel surface and thus 'unload' the panel by reducing the panel radiation impedance. In general, control by structural inputs appears more effective than control by acoustic sources for structurally radiated noise.

Application of modern radiative transfer tools to model laboratory quartz emissivity

NASA Astrophysics Data System (ADS)

Pitman, Karly M.; Wolff, Michael J.; Clayton, Geoffrey C.

2005-08-01

Planetary remote sensing of regolith surfaces requires use of theoretical models for interpretation of constituent grain physical properties. In this work, we review and critically evaluate past efforts to strengthen numerical radiative transfer (RT) models with comparison to a trusted set of nadir incidence laboratory quartz emissivity spectra. By first establishing a baseline statistical metric to rate successful model-laboratory emissivity spectral fits, we assess the efficacy of hybrid computational solutions (Mie theory + numerically exact RT algorithm) to calculate theoretical emissivity values for micron-sized α-quartz particles in the thermal infrared (2000-200 cm-1) wave number range. We show that Mie theory, a widely used but poor approximation to irregular grain shape, fails to produce the single scattering albedo and asymmetry parameter needed to arrive at the desired laboratory emissivity values. Through simple numerical experiments, we show that corrections to single scattering albedo and asymmetry parameter values generated via Mie theory become more necessary with increasing grain size. We directly compare the performance of diffraction subtraction and static structure factor corrections to the single scattering albedo, asymmetry parameter, and emissivity for dense packing of grains. Through these sensitivity studies, we provide evidence that, assuming RT methods work well given sufficiently well-quantified inputs, assumptions about the scatterer itself constitute the most crucial aspect of modeling emissivity values.

Fourth Generation Light Sources

NASA Astrophysics Data System (ADS)

Winick, Herman

1997-05-01

Concepts and designs are now being developed at laboratories around the world for light sources with performance levels that exceed present sources, including the very powerful and successful third generation synchrotron radiation sources that have come on line in the past few years. Workshops (M. Cornacchia and H. Winick (eds), Workshop on Fourth Generation Light Sources, Feb. 24-27, 1992, SSRL Report 92/02) (J.-L. Laclare (ed), ICFA Workshop on Fourth Generation Light Sources, Jan. 22-25, 1996, ESRF Report) have been held to review directions for future sources. A main thrust is to increase the brightness and coherence of the radiation using storage rings with lower electron-beam emittance or free-electron lasers (FELs). In the infra-red part of the spectrum very high brightness and coherence is already provided by FEL user facilities driven by linacs and storage rings. It now appears possible to extend FEL operation to the VUV, soft X-ray and even hard X-ray spectral range, to wavelengths down to the angstrom range, using high energy linacs equipped with high-brightness rf photoinjectors and bunch-length compressors. R&D to develop such sources is in progress at BNL, DESY, KEK, SLAC and other laboratories. In the absence of mirrors to form optical cavities, short wavelengths are reached in FEL systems in which a high peak current, low-emittance electron beam becomes bunch-density modulated at the optical wavelength in a single pass through a long undulator by self-amplified spontaneous emission (SASE); i.e.; startup from noise. A proposal to use the last kilometer of the three kilometer SLAC linac (the first two kilometers will be used for injection to the PEP II B-Factory) to provide 15 GeV electron beams to reach 1.5 Angstroms by SASE in a 100 m long undulator is in preparation.

(32)P measurment of urine samples and internal dose assessment for radiation workers in life science laboratories.

PubMed

Yoon, S; Pak, M-J; Park, S; Yoo, J; Ha, W-H; Jang, H-K; Kim, J K

2014-12-01

(32)P measurements of urine samples and internal dose assessments were conducted for workers in life science laboratories. A procedure for sample pre-treatment was established and validation was performed to exclude interference and to detect (32)P levels accurately. The detection conditions for Cherenkov radiation were evaluated and the accuracy of Cherenkov radiation measurements validated. The analytical and measurement procedures were applied to urine samples collected from 11 workers from life sciences laboratories. The results of the measurements generally indicated very low background radiation levels, but daily urine samples from two workers were above the minimum detectable activity. The (32)P concentrations for two of the workers were 29.3  ±  10.4 Bq•d(-1) and 24.1  ±  11.8 Bq•d(-1), respectively, at intake levels of 4.12 kBq and 2.61 kBq. The effective doses for these two workers were 4.6 μSv and 2.9 μSv. Overall, the results indicate very low levels of radioactivity, except for cases related to specific working conditions.

Chemical plating method of preparing radiation source material

DOEpatents

Smith, P.K.; Huntoon, R.T.; Mosley, W.C. Jr.

1973-12-11

A uniform dispersion of a radioisotope within a noble metal matrix is provided by chemically plating a noble metal coating onto particles including a dissociable compound of the mdioisotope. A suspension of the dissociable compound in a chemically reductive solution is prepared and noble metal cations added to produce the noble metal coatings. The coated particles are filtered, dried and heated to calcine the dissociable compound to a refractory powder. The powder can be encapsulated in measured portions or consolidated and shaped into an elongated form for easy apportionnnent as radiation source material. (Official Gazette)

Microscopic properties of xenon plasmas for density and temperature regimes of laboratory astrophysics experiments on radiative shocks.

PubMed

Rodríguez, R; Espinosa, G; Gil, J M; Stehlé, C; Suzuki-Vidal, F; Rubiano, J G; Martel, P; Mínguez, E

2015-05-01

This work is divided into two parts. In the first one, a study of radiative properties (such as monochromatic and the Rosseland and Planck mean opacities, monochromatic emissivities, and radiative power loss) and of the average ionization and charge state distribution of xenon plasmas in a range of plasma conditions of interest in laboratory astrophysics and extreme ultraviolet lithography is performed. We have made a particular emphasis in the analysis of the validity of the assumption of local thermodynamic equilibrium and the influence of the atomic description in the calculation of the radiative properties. Using the results obtained in this study, in the second part of the work we have analyzed a radiative shock that propagated in xenon generated in an experiment carried out at the Prague Asterix Laser System. In particular, we have addressed the effect of plasma self-absorption in the radiative precursor, the influence of the radiation emitted from the shocked shell and the plasma self-emission in the radiative precursor, the cooling time in the cooling layer, and the possibility of thermal instabilities in the postshock region.

Localization of non-stationary sources of electromagnetic radiation with the aid of phasometry

NASA Technical Reports Server (NTRS)

Mersov, G. A.

1978-01-01

The possibility of localizing sources of electromagnetic radiation by measurement of the time of passage of the radiation or the measurement of its phase at various points of cosmic space, at which are located satellite observatories is examined. Algorithms are proposed for localization using two, three, and four astronomical observatories. The precision of the localization and several partial results of practical significance are deduced.

Chemical applications of synchrotron radiation: Workshop report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1989-04-01

The most recent in a series of topical meetings for Advanced Photon Source user subgroups, the Workshop on Chemical Applications of Synchrotron Radiation (held at Argonne National Laboratory, October 3-4, 1988) dealt with surfaces and kinetics, spectroscopy, small-angle scattering, diffraction, and topography and imaging. The primary objectives were to provide an educational resource for the chemistry community on the scientific research being conducted at existing synchrotron sources and to indicate some of the unique opportunities that will be made available with the Advanced Photon Source. The workshop organizers were also interested in gauging the interest of chemists in the fieldmore » of synchrotron radiation. Interest expressed at the meeting has led to initial steps toward formation of a Chemistry Users Group at the APS. Individual projects are processed separately for the data bases.« less

On beam shaping of the field radiated by a line source coupled to finite or infinite photonic crystals.

PubMed

Ceccuzzi, Silvio; Jandieri, Vakhtang; Baccarelli, Paolo; Ponti, Cristina; Schettini, Giuseppe

2016-04-01

Comparison of the beam-shaping effect of a field radiated by a line source, when an ideal infinite structure constituted by two photonic crystals and an actual finite one are considered, has been carried out by means of two different methods. The lattice sums technique combined with the generalized reflection matrix method is used to rigorously investigate the radiation from the infinite photonic crystals, whereas radiation from crystals composed of a finite number of rods along the layers is analyzed using the cylindrical-wave approach. A directive radiation is observed with the line source embedded in the structure. With an increased separation distance between the crystals, a significant edge diffraction appears that provides the main radiation mechanism in the finite layout. Suitable absorbers are implemented to reduce the above-mentioned diffraction and the reflections at the boundaries, thus obtaining good agreement between radiation patterns of a localized line source coupled to finite and infinite photonic crystals, when the number of periods of the finite structure is properly chosen.

Location of acoustic radiators and inversion for energy density using radio-frequency sources and thunder recordings

NASA Astrophysics Data System (ADS)

Anderson, J.; Johnson, J. B.; Arechiga, R. O.; Edens, H. E.; Thomas, R. J.

2011-12-01

We use radio frequency (VHF) pulse locations mapped with the New Mexico Tech Lightning Mapping Array (LMA) to study the distribution of thunder sources in lightning channels. A least squares inversion is used to fit channel acoustic energy radiation with broadband (0.01 to 500 Hz) acoustic recordings using microphones deployed local (< 10 km) to the lightning. We model the thunder (acoustic) source as a superposition of line segments connecting the LMA VHF pulses. An optimum branching algorithm is used to reconstruct conductive channels delineated by VHF sources, which we discretize as a superposition of finely-spaced (0.25 m) acoustic point sources. We consider total radiated thunder as a weighted superposition of acoustic waves from individual channels, each with a constant current along its length that is presumed to be proportional to acoustic energy density radiated per unit length. Merged channels are considered as a linear sum of current-carrying branches and radiate proportionally greater acoustic energy. Synthetic energy time series for a given microphone location are calculated for each independent channel. We then use a non-negative least squares inversion to solve for channel energy densities to match the energy time series determined from broadband acoustic recordings across a 4-station microphone network. Events analyzed by this method have so far included 300-1000 VHF sources, and correlations as high as 0.5 between synthetic and recorded thunder energy were obtained, despite the presence of wind noise and 10-30 m uncertainty in VHF source locations.

Concept of a tunable source of coherent THz radiation driven by a plasma modulated electron beam

NASA Astrophysics Data System (ADS)

Zhang, H.; Konoplev, I. V.; Doucas, G.; Smith, J.

2018-04-01

We have carried out numerical studies which consider the modulation of a picosecond long relativistic electron beam in a plasma channel and the generation of a micro-bunched train. The subsequent propagation of the micro-bunched beam in the vacuum area was also investigated. The same numerical model was then used to simulate the radiation arising from the interaction of the micro-bunched beam with a metallic grating. The dependence of the radiation spectrum on the parameters of the micro-bunched beam has been studied and the tunability of the radiation by the variation of the micro-bunch spacing has been demonstrated. The micro-bunch spacing can be changed easily by altering the plasma density without changing the beam energy or current. Using the results of these studies, we develop a conceptual design of a tunable source of coherent terahertz (THz) radiation driven by a plasma modulated beam. Such a source would be a potential and useful alternative to conventional vacuum THz tubes and THz free-electron laser sources.

Space Radiation Effects Laboratory

NASA Technical Reports Server (NTRS)

1969-01-01

The SREL User's Handbook is designed to provide information needed by those who plan experiments involving the accelerators at this laboratory. Thus the Handbook will contain information on the properties of the machines, the beam parameters, the facilities and services provided for experimenters, etc. This information will be brought up to date as new equipment is added and modifications accomplished. This Handbook is influenced by the many excellent models prepared at other accelerator laboratories. In particular, the CERN Synchrocyclotron User's Handbook (November 1967) is closely followed in some sections, since the SREL Synchrocyclotron is a duplicate of the CERN machine. We wish to thank Dr. E. G. Michaelis for permission to draw so heavily on his work, particularly in Section II of this Handbook. We hope that the Handbook will prove useful, and will welcome suggestions and criticism.

Modelling single shot damage thresholds of multilayer optics for high-intensity short-wavelength radiation sources.

PubMed

Loch, R A; Sobierajski, R; Louis, E; Bosgra, J; Bijkerk, F

2012-12-17

The single shot damage thresholds of multilayer optics for high-intensity short-wavelength radiation sources are theoretically investigated, using a model developed on the basis of experimental data obtained at the FLASH and LCLS free electron lasers. We compare the radiation hardness of commonly used multilayer optics and propose new material combinations selected for a high damage threshold. Our study demonstrates that the damage thresholds of multilayer optics can vary over a large range of incidence fluences and can be as high as several hundreds of mJ/cm(2). This strongly suggests that multilayer mirrors are serious candidates for damage resistant optics. Especially, multilayer optics based on Li(2)O spacers are very promising for use in current and future short-wavelength radiation sources.

US Army Research Laboratory power sources R and D programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christopher, H.A.; Gilman, S.; Hamlen, R.P.

1993-05-01

The development and application of new electronic technologies over the recent past has resulted in a major evolution of new electronic battlefield equipment. The need for lighter-weight and more cost effective power sources with higher power/energy density capability is critical to the successful development and deployment of these new, high performance battlefield devices. The current status and thrust of the Army Research Laboratory's (ARL's) battery and fuel cell R and D programs that support these new and emerging applications will be reviewed. Major technical barriers will be identified along with the corresponding proposed approaches to solving these anticipated problems.

Detecting Upward Directed Charged Particle Fluxes in the Mars Science Laboratory Radiation Assessment Detector

NASA Astrophysics Data System (ADS)

Appel, J. K.; Köehler, J.; Guo, J.; Ehresmann, B.; Zeitlin, C.; Matthiä, D.; Lohf, H.; Wimmer-Schweingruber, R. F.; Hassler, D.; Brinza, D. E.; Böhm, E.; Böttcher, S.; Martin, C.; Burmeister, S.; Reitz, G.; Rafkin, S.; Posner, A.; Peterson, J.; Weigle, G.

2018-01-01

The Mars Science Laboratory rover Curiosity, operating on the surface of Mars, is exposed to radiation fluxes from above and below. Galactic Cosmic Rays travel through the Martian atmosphere, producing a modified spectrum consisting of both primary and secondary particles at ground level. These particles produce an upward directed secondary particle spectrum as they interact with the Martian soil. Here we develop a method to distinguish the upward and downward directed particle fluxes in the Radiation Assessment Detector (RAD) instrument, verify it using data taken during the cruise to Mars, and apply it to data taken on the Martian surface. We use a combination of Geant4 and Planetocosmics modeling to find discrimination criteria for the flux directions. After developing models of the cruise phase and surface shielding conditions, we compare model-predicted values for the ratio of upward to downward flux with those found in RAD observation data. Given the quality of available information on Mars Science Laboratory spacecraft and rover composition, we find generally reasonable agreement between our models and RAD observation data. This demonstrates the feasibility of the method developed and tested here. We additionally note that the method can also be used to extend the measurement range and capabilities of the RAD instrument to higher energies.

Sources of Differences in On-Orbital Total Solar Irradiance Measurements and Description of a Proposed Laboratory Intercomparison

PubMed Central

Butler, J. J; Johnson, B. C; Rice, J. P; Shirley, E. L; Barnes, R. A

2008-01-01

There is a 5 W/m2 (about 0.35 %) difference between current on-orbit Total Solar Irradiance (TSI) measurements. On 18–20 July 2005, a workshop was held at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland that focused on understanding possible reasons for this difference, through an examination of the instrument designs, calibration approaches, and appropriate measurement equations. The instruments studied in that workshop included the Active Cavity Radiometer Irradiance Monitor III (ACRIM III) on the Active Cavity Radiometer Irradiance Monitor SATellite (ACRIMSAT), the Total Irradiance Monitor (TIM) on the Solar Radiation and Climate Experiment (SORCE), the Variability of solar IRradiance and Gravity Oscillations (VIRGO) on the Solar and Heliospheric Observatory (SOHO), and the Earth Radiation Budget Experiment (ERBE) on the Earth Radiation Budget Satellite (ERBS). Presentations for each instrument included descriptions of its design, its measurement equation and uncertainty budget, and the methods used to assess on-orbit degradation. The workshop also included a session on satellite- and ground-based instrument comparisons and a session on laboratory-based comparisons and the application of new laboratory comparison techniques. The workshop has led to investigations of the effects of diffraction and of aperture area measurements on the differences between instruments. In addition, a laboratory-based instrument comparison is proposed that uses optical power measurements (with lasers that underfill the apertures of the TSI instruments), irradiance measurements (with lasers that overfill the apertures of the TSI instrument), and a cryogenic electrical substitution radiometer as a standard for comparing the instruments. A summary of the workshop and an overview of the proposed research efforts are presented here. PMID:27096120

Submillimeter Laboratory Investigations: Spectroscopy and Collisions

NASA Technical Reports Server (NTRS)

Herbst, Eric; DeLucia, Frank C.

2002-01-01

Currently, millimeter-wave and submillimeter-wave spectroscopy is conducted in our laboratory on several different types of spectrometers. Our standard spectrometer utilizes the output of a phase-locked klystron operating in the 40-60 GHz region, which is sent into a crossed-waveguide harmonic generator, or "multiplier". The high frequency millimeter-and submillimeter-wave radiation is transmitted via quasi-optical techniques through an absorption cell and then onto a detector, which is either an InSb hot electron bolometer cooled to 1.4 K or a Si bolometer cooled to 0.3 K. The detector response is sent to a computer for measurement and analysis. The frequency range produced and detected in this manner goes from 80 GHz to upwards of 1 THz. Spectra are normally taken with source modulation, with line frequencies typically measured to an accuracy of 50-100 kHz. Higher accuracy is available when needed. Recently, we developed a new, broad-band spectrometer in our laboratory based on a free-running backward wave oscillator (BWO) of Russian manufacture as the primary source of radiation. The so-called FASSST (fast-scan submillimeter spectroscopic technique) system uses fast-scan and optical calibration methods rather than the traditional locking techniques. The output power from the BWO is split such that 90% goes into the absorption cell while 10% is coupled to a 40-meter Fabry-Perot cavity, which yields fringe? for frequency measurement. Results from this spectrometer on the spectrum of nitric acid (HNO3) show that 100 GHz of spectral data can be obtained in 5 seconds with a measurement accuracy of 50 kHz. Currently, the frequency range of the FASSST system in our laboratory is roughly 100-700 GHz.

Experimental validation of a coupled neutron-photon inverse radiation transport solver

NASA Astrophysics Data System (ADS)

Mattingly, John; Mitchell, Dean J.; Harding, Lee T.

2011-10-01

Sandia National Laboratories has developed an inverse radiation transport solver that applies nonlinear regression to coupled neutron-photon deterministic transport models. The inverse solver uses nonlinear regression to fit a radiation transport model to gamma spectrometry and neutron multiplicity counting measurements. The subject of this paper is the experimental validation of that solver. This paper describes a series of experiments conducted with a 4.5 kg sphere of α-phase, weapons-grade plutonium. The source was measured bare and reflected by high-density polyethylene (HDPE) spherical shells with total thicknesses between 1.27 and 15.24 cm. Neutron and photon emissions from the source were measured using three instruments: a gross neutron counter, a portable neutron multiplicity counter, and a high-resolution gamma spectrometer. These measurements were used as input to the inverse radiation transport solver to evaluate the solver's ability to correctly infer the configuration of the source from its measured radiation signatures.

Effect of Different Solar Radiation Data Sources on the Variation of Techno-Economic Feasibility of PV Power System

NASA Astrophysics Data System (ADS)

Alghoul, M. A.; Ali, Amer; Kannanaikal, F. V.; Amin, N.; Aljaafar, A. A.; Kadhim, Mohammed; Sopian, K.

2017-11-01

The aim of this study is to evaluate the variation in techno-economic feasibility of PV power system under different data sources of solar radiation. HOMER simulation tool is used to predict the techno-economic feasibility parameters of PV power system in Baghdad city, Iraq located at (33.3128° N, 44.3615° E) as a case study. Four data sources of solar radiation, different annual capacity shortages percentage (0, 2.5, 5, and 7.5), and wide range of daily load profile (10-100 kWh/day) are implemented. The analyzed parameters of the techno-economic feasibility are COE (/kWh), PV array power capacity (kW), PV electrical production (kWh/year), No. of batteries and battery lifetime (year). The main results of the study revealed the followings: (1) solar radiation from different data sources caused observed to significant variation in the values of the techno-economic feasibility parameters; therefore, careful attention must be paid to ensure the use of an accurate solar input data; (2) Average solar radiation from different data sources can be recommended as a reasonable input data; (3) it is observed that as the size and of PV power system increases, the effect of different data sources of solar radiation increases and causes significant variation in the values of the techno-economic feasibility parameters.

Detection of high-frequency radiation sources during the 2004 Parkfield earthquake by a matched filter analysis

NASA Astrophysics Data System (ADS)

Uchide, T.; Shearer, P. M.

2009-12-01

Introduction Uchide and Ide [SSA Spring Meeting, 2009] proposed a new framework for studying the scaling and overall nature of earthquake rupture growth in terms of cumulative moment functions. For better understanding of rupture growth processes, spatiotemporally local processes are also important. The nature of high-frequency (HF) radiation has been investigated for some time, but its role in the earthquake rupture process is still unclear. A wavelet analysis reveals that the HF radiation (e.g., 4 - 32 Hz) of the 2004 Parkfield earthquake is peaky, which implies that the sources of the HF radiation are isolated in space and time. We experiment with applying a matched filter analysis using small template events occurring near the target event rupture area to test whether it can reveal the HF radiation sources for a regular large earthquake. Method We design a matched filter for multiple components and stations. Shelly et al. [2007] attempted identifying low-frequency earthquakes (LFE) in non-volcanic tremor waveforms by stacking the correlation coefficients (CC) between the seismograms of the tremor and the LFE. Differing from their method, our event detection indicator is the CC between the seismograms of the target and template events recorded at the same stations, since the key information for detecting the sources will be the arrival-time differences and the amplitude ratios among stations. Data from both the target and template events are normalized by the maximum amplitude of the seismogram of the template event in the cross-correlation time window. This process accounts for the radiation pattern and distance between the source and stations. At each small earthquake target, high values in the CC time series suggest the possibility of HF radiation during the mainshock rupture from a similar location to the target event. Application to the 2004 Parkfield earthquake We apply the matched filter method to the 2004 Parkfield earthquake (Mw 6.0). We use seismograms

Consideration of the Protection Curtain's Shielding Ability after Identifying the Source of Scattered Radiation in the Angiography.

PubMed

Sato, Naoki; Fujibuchi, Toshioh; Toyoda, Takatoshi; Ishida, Takato; Ohura, Hiroki; Miyajima, Ryuichi; Orita, Shinichi; Sueyoshi, Tomonari

2017-06-15

To decrease radiation exposure to medical staff performing angiography, the dose distribution in the angiography was calculated in room using the particle and heavy ion transport code system (PHITS), which is based on Monte Carlo code, and the source of scattered radiation was confirmed using a tungsten sheet by considering the difference shielding performance among different sheet placements. Scattered radiation generated from a flat panel detector, X-ray tube and bed was calculated using the PHITS. In this experiment, the source of scattered radiation was identified as the phantom or acrylic window attached to the X-ray tube thus, a protection curtain was placed on the bed to shield against scattered radiation at low positions. There was an average difference of 20% between the measured and calculated values. The H*(10) value decreased after placing the sheet on the right side of the phantom. Thus, the curtain could decrease scattered radiation. © Crown copyright 2016.

The MCART radiation physics core: the quest for radiation dosimetry standardization.

PubMed

Kazi, Abdul M; MacVittie, Thomas J; Lasio, Giovanni; Lu, Wei; Prado, Karl L

2014-01-01

Dose-related radiobiological research results can only be compared meaningfully when radiation dosimetry is standardized. To this purpose, the National Institute of Allergy and Infectious Diseases (NIAID)-sponsored Medical Countermeasures Against Radiological Threats (MCART) consortium recently created a Radiation Physics Core (RPC) as an entity to assume responsibility of standardizing radiation dosimetry practices among its member laboratories. The animal research activities in these laboratories use a variety of ionizing photon beams from several irradiators such as 250-320 kVp x-ray generators, Cs irradiators, Co teletherapy machines, and medical linear accelerators (LINACs). In addition to this variety of sources, these centers use a range of irradiation techniques and make use of different dose calculation schemes to conduct their experiments. An extremely important objective in these research activities is to obtain a Dose Response Relationship (DRR) appropriate to their respective organ-specific models of acute and delayed radiation effects. A clear and unambiguous definition of the DRR is essential for the development of medical countermeasures. It is imperative that these DRRs are transparent between centers. The MCART RPC has initiated the establishment of standard dosimetry practices among member centers and is introducing a Remote Dosimetry Monitoring Service (RDMS) to ascertain ongoing quality assurance. This paper will describe the initial activities of the MCART RPC toward implementing these standardization goals. It is appropriate to report a summary of initial activities with the intent of reporting the full implementation at a later date.

Laser ion source activities at Brookhaven National Laboratory

DOE PAGES

Kanesue, Takeshi; Okamura, Masahiro

2015-07-31

In Brookhaven National Laboratory (BNL), we have been developing laser ion sources for diverse accelerators. Tabletop Nd:YAG lasers with up to several Joules of energy are mainly used to create ablation plasmas for stable operations. The obtained charge states depend on laser power density and target species. Two types of ion extraction schemes, Direct Plasma Injection Scheme (DPIS) and conventional static extraction, are used depending on application. We optimized and select a suitable laser irradiation condition and a beam extraction scheme to meet the requirement of the following accelerator system. We have demonstrated to accelerate more than 5 x 10more » 10 of C 6+ ions using the DPIS. We successfully commissioned low charge ion beam provider to the user facilities in BNL. As a result, to achieve higher current, higher charge state and lower emittance, further studies will continue.« less

Laboratory study of PCBs transport from primary sources to ...

EPA Pesticide Factsheets

The sorption of airborne polychlorinated biphenyls (PCBs) by twenty building materials and their subsequent re-emission (desorption) from concrete were investigated using two 53-L environmental chambers connected in series with a field-collected caulk in the source chamber serving as a stable source of PCBs and building materials in the test chamber. During the tests, the PCB concentrations in the outlet air of the test chamber were monitored and the building materials were removed from the test chamber at different times to determine their PCB content. Among the materials tested, a petroleum-based paint, a latex paint, and a certain type of carpet were among the strongest sinks. Solvent-free epoxy coating, certain types of flooring materials, and brick were among the weakest sinks. For a given sink material, PCB congeners with lower vapor pressures were sorbed in larger quantities. Rough estimates of the partition and diffusion coefficients were obtained by applying a sink model to the data acquired from the chamber studies. A desorption test with the concrete panels showed that re-emission is a slow process, suggesting that PCB sinks, e.g. concrete, can release PCBs into the air for a prolonged period of time (years or decades). This study could fill some of the data gaps associated with the characterization of PCB sinks in contaminated buildings. This paper summarizes the laboratory research results for PCB transport from primary sources to PCB sinks, includ

Rf system for the NSLS coherent infrared radiation source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Broome, W.; Biscardi, R.; Keane, J.

1995-05-01

The existing NSLS X-ray Lithography Source (XLS Phase I) is being considered for a coherent synchrotron radiation source. The existing 211 MHz warm cavity will be replaced with a 5-cell 2856 MHz superconducting RF cavity, driven by a series of 2 kW klystrons. The RF system will provide a total V{sub RF} of 1.5 MV to produce {sigma}{sub L} = 0.3 mm electron bunches at an energy of 150 MeV. Superconducting technology significantly reduces the required space and power needed to achieve the higher voltage. It is the purpose of this paper to describe the superconducting RF system and cavity,more » power requirements, and cavity design parameters such as input coupling, Quality Factor, and Higher Order Modes.« less

Analysis of gamma radiation from a radon source: Indications of a solar influence

NASA Astrophysics Data System (ADS)

Sturrock, P. A.; Steinitz, G.; Fischbach, E.; Javorsek, D.; Jenkins, J. H.

2012-08-01

This article presents an analysis of about 29,000 measurements of gamma radiation associated with the decay of radon in a sealed container at the Geological Survey of Israel (GSI) Laboratory in Jerusalem between 28 January 2007 and 10 May 2010. These measurements exhibit strong variations in time of year and time of day, which may be due in part to environmental influences. However, time-series analysis reveals a number of periodicities, including two at approximately 11.2 year-1 and 12.5 year-1. We have previously found these oscillations in nuclear-decay data acquired at the Brookhaven National Laboratory and at the Physiklisch-Technische Bundesanstalt, and we have suggested that these oscillations are attributable to some form of solar radiation that has its origin in the deep solar interior. A curious property of the GSI data is that the annual oscillation is much stronger in daytime data than in nighttime data, but the opposite is true for all other oscillations. This may be a systematic effect but, if it is not, this property should help narrow the theoretical options for the mechanism responsible for decay-rate variability.

Attenuation of radiation from distributed gamma sources as a function of wall thickness of a concrete blockhouse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmoke, M. A.; Rexroad, R. E.; Tiller, H. J.

1963-06-15

The experiment described constitutes part of the shielding program conducted by Army Nuclear Defense Laboratory and was designed to experimentally verify theoretical calculations used to predict the amount of radiation protection afforded by above-ground structures in a fallout radiation field. This method requires the knowledge of some physical parameters of a structure such as mass thickness of the walls and the geometric orientation of the detectors within the structure. From this information, a reduction factor for any given structure may be calculated. This Laboratory's experimental program was initially begun by measuring the attenuation of a simple structure with no complicatingmore » internal or external geometries and will proceed to more complex structures with basements, interior partitions, and upper floors. (auth)« less

Radiative flux from a planar multiple point source within a cylindrical enclosure reaching a coaxial circular plane

NASA Astrophysics Data System (ADS)

Tryka, Stanislaw

2007-04-01

A general formula and some special integral formulas were presented for calculating radiative fluxes incident on a circular plane from a planar multiple point source within a coaxial cylindrical enclosure perpendicular to the source. These formula were obtained for radiation propagating in a homogeneous isotropic medium assuming that the lateral surface of the enclosure completely absorbs the incident radiation. Exemplary results were computed numerically and illustrated with three-dimensional surface plots. The formulas presented are suitable for determining fluxes of radiation reaching planar circular detectors, collectors or other planar circular elements from systems of laser diodes, light emitting diodes and fiber lamps within cylindrical enclosures, as well as small biological emitters (bacteria, fungi, yeast, etc.) distributed on planar bases of open nontransparent cylindrical containers.

A laboratory study of the lambda 2145 A auroral mystery feature

NASA Technical Reports Server (NTRS)

Erdman, P. W.; Espy, P. J.; Zipf, E. C.

1980-01-01

The prominent emission feature near 2145 A in the ultraviolet spectrum of an aurora has been tentatively identified by Dick (1978) as the doublet lines, 2139.68 A and 2143.55 A, emitted by metastable N+(5S) ions, and dissociative excitation of N2 by electron impact with a cross section greater than or equal to 2 x 10 to the -18th sq cm has been proposed as the source of this species. A detailed laboratory study of dissociative excitation is described that suggests two alternative viewpoints of this process: (1) If the calculated radiative lifetime for the N+(5S) state (4.4 microsec) is correct, then the N+(5S) dissociative excitation cross section is less than 3 x 10 to the -21st sq cm. Thus, a new N+(5S) source mechanism would have to be found in order to account for the auroral data. (2) If dissociative excitation does form N+(5S) ions efficiently, then the laboratory and field observations imply a radiative lifetime for this state of more than 10 msec, thus suggesting that there are major errors in the lifetime computation.

Sirepo for Synchrotron Radiation Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagler, Robert; Moeller, Paul; Rakitin, Maksim

Sirepo is an open source framework for cloud computing. The graphical user interface (GUI) for Sirepo, also known as the client, executes in any HTML5 compliant web browser on any computing platform, including tablets. The client is built in JavaScript, making use of the following open source libraries: Bootstrap, which is fundamental for cross-platform web applications; AngularJS, which provides a model–view–controller (MVC) architecture and GUI components; and D3.js, which provides interactive plots and data-driven transformations. The Sirepo server is built on the following Python technologies: Flask, which is a lightweight framework for web development; Jinja, which is a secure andmore » widely used templating language; and Werkzeug, a utility library that is compliant with the WSGI standard. We use Nginx as the HTTP server and proxy, which provides a scalable event-driven architecture. The physics codes supported by Sirepo execute inside a Docker container. One of the codes supported by Sirepo is the Synchrotron Radiation Workshop (SRW). SRW computes synchrotron radiation from relativistic electrons in arbitrary magnetic fields and propagates the radiation wavefronts through optical beamlines. SRW is open source and is primarily supported by Dr. Oleg Chubar of NSLS-II at Brookhaven National Laboratory.« less

The space experiment CERASP: Definition of a space-suited radiation source and growth conditions for human cells

NASA Astrophysics Data System (ADS)

Hellweg, Christine E.; Baumstark-Khan, Christa; Spitta, Luis; Thelen, Melanie; Arenz, Andrea; Franz, Markus; Schulze-Varnholt, Dirk; Berger, Thomas; Reitz, Günther

The combined action of ionizing radiation and microgravity will continue to influence future space missions, with special risks for astronauts on the Moon surface or for long duration missions to Mars. It has been estimated that on a 3-year mission to Mars about 3% of the bodies' cell nuclei would have been hit by one iron ion with the consequence that nuclear DNA will be heavily damaged. There is increasing evidence that basic cellular functions are sensitive not only to radiation but also to microgravity. DNA repair studies in space on bacteria, yeast cells and human fibroblasts, which were irradiated before, flight, gave contradictory results: from inhibition of repair by microgravity to enhancement, whereas others did not detect any influence of microgravity on repair. The space experiment CERASP (CEllular Responses to RAdiation in SPace) to be performed at the International Space Station (ISS) is aimed to supply basic information on the cellular response in microgravity to radiation applied during flight. It makes use of a recombinant human cell line as reporter for cellular signal transduction modulation by genotoxic environmental conditions. The main biological endpoints under investigation will be gene activation based on enhanced green fluorescent protein (EGFP, originally isolated from the bioluminescent jellyfish Aequorea victoria) expression controlled by a DNA damage-dependent promoter element which reflects the activity of the nuclear factor kappa B (NF- κB) pathway. The NF- κB family of proteins plays a major role in the inflammatory and immune response, cell proliferation and differentiation, anti-apoptosis and tumorgenesis. For radiation exposure during space flight a radiation source has been constructed as damage accumulation by cosmic radiation will certainly be insufficient for analysis. The space experiment specific hardware consists of a specially designed radiation source made up of the β-emitter promethium-147, combined with a

ZeBase: an open-source relational database for zebrafish laboratories.

PubMed

Hensley, Monica R; Hassenplug, Eric; McPhail, Rodney; Leung, Yuk Fai

2012-03-01

Abstract ZeBase is an open-source relational database for zebrafish inventory. It is designed for the recording of genetic, breeding, and survival information of fish lines maintained in a single- or multi-laboratory environment. Users can easily access ZeBase through standard web-browsers anywhere on a network. Convenient search and reporting functions are available to facilitate routine inventory work; such functions can also be automated by simple scripting. Optional barcode generation and scanning are also built-in for easy access to the information related to any fish. Further information of the database and an example implementation can be found at http://zebase.bio.purdue.edu.

76 FR 76327 - Installation of Radiation Alarms for Rooms Housing Neutron Sources

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-07

... NUCLEAR REGULATORY COMMISSION 10 CFR Part 73 [Docket Nos. PRM-73-15; NRC-2011-0251] Installation of Radiation Alarms for Rooms Housing Neutron Sources AGENCY: Nuclear Regulatory Commission. ACTION: Petition for rulemaking; request for comment. SUMMARY: The U.S. Nuclear Regulatory Commission (NRC or the...

Laser-plasma accelerator and femtosecond photon sources-based ultrafast radiation chemistry and biophysics

NASA Astrophysics Data System (ADS)

Gauduel, Y. A.

2017-02-01

The initial distribution of energy deposition triggered by the interaction of ionizing radiations (far UV and X rays, electron, proton and accelerated ions) with molecular targets or integrated biological systems is often decisive for the spatio-temporal behavior of radiation effects that take place on several orders of magnitude. This contribution deals with an interdisciplinary approach that concerns cutting-edge advances on primary radiation events, considering the potentialities of innovating strategies based on ultrafast laser science, from femtosecond photon sources to laser-driven relativistic particles acceleration. Recent advances of powerful TW laser sources (~ 1019 Wcm-2) and laser-plasma interactions providing ultrashort relativistic particle beams in the energy domain 2.5-150 MeV open exciting opportunities for the development of high-energy radiation femtochemistry (HERF). Early radiation damages being dependent on the survival probability of secondary electrons and radial distribution of short-lived radicals inside ionization clusters, a thorough knowledge of these processes involves the real-time probing of primary events in the temporal range 10-14-10-11 s. In the framework of a closed synergy between low-energy radiation femtochemistry (LERF) and the emerging domain of HERF, the paper focuses on early phenomena that occur in the prethermal regime of low-energy secondary electrons, considering very short-lived quantum effects in aqueous environments. A high dose-rate delivered by femtosecond electron beam (~ 1011-1013 Gy s-1) can be used to investigate early radiation processes in native ionization tracks, down to 10-12 s and 10-9 m. We explain how this breakthrough favours the innovating development of real-time nanodosimetry in biologically relevant environments and open new perspectives for spatio-temporal radiation biophysics. The emerging domain of HERF would provide guidance for understanding the specific bioeffects of ultrashort particle

Development and analysis of a meteorological database, Argonne National Laboratory, Illinois

USGS Publications Warehouse

Over, Thomas M.; Price, Thomas H.; Ishii, Audrey L.

2010-01-01

A database of hourly values of air temperature, dewpoint temperature, wind speed, and solar radiation from January 1, 1948, to September 30, 2003, primarily using data collected at the Argonne National Laboratory station, was developed for use in continuous-time hydrologic modeling in northeastern Illinois. Missing and apparently erroneous data values were replaced with adjusted values from nearby stations used as 'backup'. Temporal variations in the statistical properties of the data resulting from changes in measurement and data-storage methodologies were adjusted to match the statistical properties resulting from the data-collection procedures that have been in place since January 1, 1989. The adjustments were computed based on the regressions between the primary data series from Argonne National Laboratory and the backup series using data obtained during common periods; the statistical properties of the regressions were used to assign estimated standard errors to values that were adjusted or filled from other series. Each hourly value was assigned a corresponding data-source flag that indicates the source of the value and its transformations. An analysis of the data-source flags indicates that all the series in the database except dewpoint have a similar fraction of Argonne National Laboratory data, with about 89 percent for the entire period, about 86 percent from 1949 through 1988, and about 98 percent from 1989 through 2003. The dewpoint series, for which observations at Argonne National Laboratory did not begin until 1958, has only about 71 percent Argonne National Laboratory data for the entire period, about 63 percent from 1948 through 1988, and about 93 percent from 1989 through 2003, indicating a lower reliability of the dewpoint sensor. A basic statistical analysis of the filled and adjusted data series in the database, and a series of potential evapotranspiration computed from them using the computer program LXPET (Lamoreux Potential

Physics of compact nonthermal sources. III - Energetic considerations. [electron synchrotron radiation

NASA Technical Reports Server (NTRS)

Burbidge, G. R.; Jones, T. W.; Odell, S. L.

1974-01-01

The energy content of the compact incoherent electron-synchrotron sources 3C 84, 3C 120, 3C 273, 3C 279, 3C 454.3, CTA 102, 3C 446, PKS 2134+004, VRO 42.22.01 and OJ 287 is calculated on the assumption that the low-frequency turnovers in the radio spectrum are due to self-absorption and that the electron distribution is isotropic. The dependence of the source parameters on various modifications of the standard assumptions is determined. These involve relativistic motions, alternate explanations for the low-frequency turnover, proton-synchrotron radiation, and distance to the source. The canonical interpretation is found to be accurate in many respects; some of the difficulties and ways of dealing with them are discussed in detail.

Simulation of multi-element multispectral UV radiation source for optical-electronic system of minerals luminescence analysis

NASA Astrophysics Data System (ADS)

Peretyagin, Vladimir S.; Korolev, Timofey K.; Chertov, Aleksandr N.

2017-02-01

The problems of dressability the solid minerals are attracted attention of specialists, where the extraction of mineral raw materials is a significant sector of the economy. There are a significant amount of mineral ore dressability methods. At the moment the radiometric dressability methods are considered the most promising. One of radiometric methods is method photoluminescence. This method is based on the spectral analysis, amplitude and kinetic parameters luminescence of minerals (under UV radiation), as well as color parameters of radiation. The absence of developed scientific and methodological approaches of analysis irradiation area to UV radiation as well as absence the relevant radiation sources are the factors which hinder development and use of photoluminescence method. The present work is devoted to the development of multi-element UV radiation source designed for the solution problem of analysis and sorting minerals by their selective luminescence. This article is presented a method of theoretical modeling of the radiation devices based on UV LEDs. The models consider such factors as spectral component, the spatial and energy parameters of the LEDs. Also, this article is presented the results of experimental studies of the some samples minerals.

Undulator Radiation Damage Experience at LCLS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nuhn, H. D.; Field, C.; Mao, S.

2015-01-06

The SLAC National Accelerator Laboratory has been running the Linac Coherent Light Source (LCLS), the first x-ray Free Electron Laser since 2009. Undulator magnet damage from radiation, produced by the electron beam traveling through the 133-m long straight vacuum tube, has been and is a concern. A damage measurement experiment has been performed in 2007 in order to obtain dose versus damage calibrations. Radiation reduction and detection devices have been integrated into the LCLS undulator system. The accumulated radiation dose rate was continuously monitored and recorded. In addition, undulator segments have been routinely removed from the beamline to be checkedmore » for magnetic (50 ppm, rms) and mechanic (about 0.25 µm, rms) changes. A reduction in strength of the undulator segments is being observed, at a level, which is now clearly above the noise. Recently, potential sources for the observed integrated radiation levels have been investigated. The paper discusses the results of these investigation as well as comparison between observed damage and measured dose accumulations and discusses, briefly, strategies for the new LCLS-II upgrade, which will be operating at more than 300 times larger beam rate.« less

Radiation exposure from consumer products and miscellaneous sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1977-01-01

This review of the literature indicates that there is a variety of consumer products and miscellaneous sources of radiation that result in exposure to the U.S. population. A summary of the number of people exposed to each such source, an estimate of the resulting dose equivalents to the exposed population, and an estimate of the average annual population dose equivalent are tabulated. A review of the data in this table shows that the total average annual contribution to the whole-body dose equivalent of the U.S. population from consumer products is less than 5 mrem; about 70 percent of this arisesmore » from the presence of naturally-occurring radionuclides in building materials. Some of the consumer product sources contribute exposure mainly to localized tissues or organs. Such localized estimates include: 0.5 to 1 mrem to the average annual population lung dose equivalent (generalized); 2 rem to the average annual population bronchial epithelial dose equivalent (localized); and 10 to 15 rem to the average annual population basal mucosal dose equivalent (basal mucosa of the gum). Based on these estimates, these sources may be grouped or classified as those that involve many people and the dose equivalent is relative large or those that involve many people but the dose equivalent is relatively small, or the dose equivalent is relatively large but the number of people involved is small.« less

Extinction cross-section cancellation of a cylindrical radiating active source near a rigid corner and acoustic invisibility

NASA Astrophysics Data System (ADS)

Mitri, F. G.

2017-11-01

Active cloaking in its basic form requires that the extinction cross-section (or energy efficiency) from a radiating body vanishes. In this analysis, this physical effect is demonstrated for an active cylindrically radiating acoustic source in a non-viscous fluid, undergoing periodic axisymmetric harmonic vibrations near a rigid corner (i.e., quarter-space). The rigorous multipole expansion method in cylindrical coordinates, the method of images, and the addition theorem of cylindrical wave functions are used to derive closed-form mathematical expressions for the radiating, amplification, and extinction cross-sections of the active source. Numerical computations are performed assuming monopole and dipole modal oscillations of the circular source. The results reveal some of the situations where the extinction energy efficiency factor of the active source vanishes depending on its size and location with respect to the rigid corner, thus, achieving total invisibility. Moreover, the extinction energy efficiency factor varies between positive or negative values. These effects also occur for higher-order modal oscillations of the active source. The results find potential applications in the development of acoustic cloaking devices and invisibility in underwater acoustics or other areas.

A New Fundamental Plane for Radiatively Efficient Black-hole Sources

NASA Astrophysics Data System (ADS)

Dong, Ai-Jun; Wu, Qingwen; Cao, Xiao-Feng

2014-06-01

In recent years, it has been found that several low/hard states of X-ray binaries (XRBs) follow an "outliers" track in the radio-X-ray correlation (L_R\\propto L_X^{b} and b ~ 1.4), which is much steeper than the former universal track with b ~ 0.6. In this work, we compile a sample of bright radio-quiet active galactic nuclei (AGNs) and find that their hard X-ray photon indices and Eddington ratios are positively correlated, which is similar to that of XRB outliers, where both bright AGNs and XRB outliers have bolometric Eddington ratios >~ 1%L Edd (L Edd is Eddington luminosity). The Eddington-scaled radio-X-ray correlation of these AGNs is also similar to that of XRB outliers, which has the form of L 5 GHz/L Eddvprop(L 2-10 keV/L Edd) c with c ~= 1.59 and 1.53 for AGNs and XRBs, respectively. Both the positively correlated X-ray spectral evolution and the steeper radio-X-ray correlation can be regulated by a radiatively efficient accretion flow (e.g., disk-corona). Based on these similarities, we further present a new fundamental plane for XRB outliers and bright AGNs in black-hole (BH) mass, radio, and X-ray luminosity space: log L_R=1.59^{+0.28}_{-0.22} log L_X- 0.22^{+0.19}_{-0.20}log M_BH-28.97^{+0.45}_{-0.45} with a scatter of σR = 0.51 dex. This fundamental plane is suitable for radiatively efficient BH sources, while the former plane proposed by Merloni et al. and Falcke et al. may be most suitable for radiatively inefficient sources.

Relativistic radiative transfer in a moving stratus irradiated by a luminous flat source

NASA Astrophysics Data System (ADS)

Fukue, Jun

2015-06-01

Relativistic radiative transfer in a geometrically thin stratus (sheet-like gaseous cloud with finite optical depth), which is moving at a relativistic speed around a luminous flat source, such as accretion disks, and is irradiated by the source, is examined under the special relativistic treatment. Incident radiation is aberrated and Doppler-shifted when it is received by the stratus, and emitted radiation is also aberrated and Doppler-shifted when it leaves the stratus. Considering these relativistic effects, we analytically obtain the emergent intensity as well as other radiative quantities in the purely scattering case for both infinite and finite strati. We mainly consider the frequency-integrated case, but also briefly show the frequency-dependent one. We also solve the relativistic radiative transfer equation numerically, and compare the results with the analytical solutions. In the infinite stratus, the mean intensity in the comoving and inertial frames decreases and becomes constant, as the stratus speed increases. The flux in the comoving frame decreases exponentially with the optical depth. The emergent intensity decreases as the speed increases, since the incident photons are redshifted at the bottom-side of the stratus. In the finite stratus, the mean intensity in the comoving and inertial frames quickly increases in the top-side region due to the aberrated photons. The flux in the comoving frame is positive in the range of 0 < β ≤ 0.4, while it becomes negative for β ≳ 0.5. The behavior of the emergent intensity is similar to that of the infinite case, although there is an irradiation effect caused by the aberrated photons.

Analysis of gamma radiation from a radon source. II: Indications of influences of both solar and cosmic neutrinos on beta decays

NASA Astrophysics Data System (ADS)

Sturrock, P. A.; Steinitz, G.; Fischbach, E.

2018-07-01

In the first article in this series, we reported an analysis of 29,000 hourly measurements of gamma radiation associated with the decay of radon gas in a sealed container at the Geological Survey of Israel (GSI) Laboratory in Jerusalem (Sturrock et al., 2012). We now report an analysis of a full 10 years of operation that yields over 85,000 hourly gamma measurements. To avoid possible confusion with seasonal environmental influences, we pay special attention to oscillations with frequencies in a band relevant to solar rotation, identifying two striking oscillations with frequencies 11.35 year-1 and 12.63 year-1, which we have found to be prominent also in decay data acquired at the Brookhaven National Laboratory (Sturrock et al., 2016). The 12.63 year-1 frequency agrees with the synodic rotational frequency (the frequency as observed on Earth) of the radiative zone as determined by helioseismology. Significantly, the more prominent rotational oscillations occur in pairs separated by 1 year-1, indicating that the solar sources of modulation rotate about axes that are oblique with respect to the normal to the ecliptic. It is notable that one of a triplet of such oscillations has exactly the same frequency (9.43 year-1) as the most significant oscillation in Super-Kamiokande measurements, suggesting that the experiment is responding to the influence of neutrinos. As found in our previous article, the annual oscillation is (counter-intuitively) stronger by day (with phase of maximum near 0.5, i.e. mid-year, suggestive of a cosmic source) than by night (with phase of maximum near zero, as expected for a solar source). This day-night asymmetry in the measurements may be understood in terms of a combined influence of asymmetries in the experiment and in the relevant nuclear processes. Spectrograms (with axes local hour of day and frequency) formed from the ambient temperature and pressure and the supply voltage differ significantly from the corresponding spectrogram

32 CFR 655.10 - Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10).

Code of Federal Regulations, 2012 CFR

2012-07-01

... land by non-Army entities (AR 385-10). 655.10 Section 655.10 National Defense Department of Defense... Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10). (a) As used in this... possession of ionizing radiation sources by non-Army entities (including their civilian contractors) on an...

32 CFR 655.10 - Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10).

Code of Federal Regulations, 2011 CFR

2011-07-01

... land by non-Army entities (AR 385-10). 655.10 Section 655.10 National Defense Department of Defense... Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10). (a) As used in this... possession of ionizing radiation sources by non-Army entities (including their civilian contractors) on an...

32 CFR 655.10 - Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10).

Code of Federal Regulations, 2013 CFR

2013-07-01

... land by non-Army entities (AR 385-10). 655.10 Section 655.10 National Defense Department of Defense... Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10). (a) As used in this... possession of ionizing radiation sources by non-Army entities (including their civilian contractors) on an...

32 CFR 655.10 - Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10).

Code of Federal Regulations, 2014 CFR

2014-07-01

... land by non-Army entities (AR 385-10). 655.10 Section 655.10 National Defense Department of Defense... Oversight of radiation sources brought on Army land by non-Army entities (AR 385-10). (a) As used in this... possession of ionizing radiation sources by non-Army entities (including their civilian contractors) on an...

[The opportunity to use combined stem cells transplantation for haemopoesis activation in the old and mature laboratory animals under the conditions of ionizing radiation].

PubMed

Grebnev, D Iu; Maklakova, I Iu; Iastrebov, A P

2014-01-01

The objective of this work was to study the influence of combined transplantation of stem cells (multypotent mesenchimal stromal and haemopoetic stem cells) on the haemopoesis of old and mature laboratory animals under the condition of ionizing radiation. The result of the experiment shows that under physiological conditions the combined transplantation brings the erithropoesis activation, under the ionizing radiation conditions it brings the erythroid and granulocytopoesis activation. Moreover the combined MMSC and HSC transplantation gives cytoprotective action on the myeloid tissue due to decrease of cyto genically changed cells in the mature animals under the condition of ionizing radiation, but in the old animals this effect can be seen even under physiological condition. Combined transplantation of MMSC and GSC can be used in the mature and old laboratory animals under the conditions of ionising radiation for the haemopoesis activation.

Rock Formation and Cosmic Radiation Exposure Ages in Gale Crater Mudstones from the Mars Science Laboratory

NASA Astrophysics Data System (ADS)

Mahaffy, Paul; Farley, Ken; Malespin, Charles; Gellert, Ralph; Grotzinger, John

2014-05-01

The quadrupole mass spectrometer (QMS) in the Sample Analysis at Mars (SAM) suite of the Mars Science Laboratory (MSL) has been utilized to secure abundances of 3He, 21Ne, 36Ar, and 40Ar thermally evolved from the mudstone in the stratified Yellowknife Bay formation in Gale Crater. As reported by Farley et al. [1] these measurements of cosmogenic and radiogenic noble gases together with Cl and K abundances measured by MSL's alpha particle X-ray spectrometer enable a K-Ar rock formation age of 4.21+0.35 Ga to be established as well as a surface exposure age to cosmic radiation of 78+30 Ma. Understanding surface exposures to cosmic radiation is relevant to the MSL search for organic compounds since even the limited set of studies carried out, to date, indicate that even 10's to 100's of millions of years of near surface (1-3 meter) exposure may transform a significant fraction of the organic compounds exposed to this radiation [2,3,4]. Transformation of potential biosignatures and even loss of molecular structural information in compounds that could point to exogenous or endogenous sources suggests a new paradigm in the search for near surface organics that incorporates a search for the most recently exposed outcrops through erosional processes. The K-Ar rock formation age determination shows promise for more precise in situ measurements that may help calibrate the martian cratering record that currently relies on extrapolation from the lunar record with its ground truth chronology with returned samples. We will discuss the protocol for the in situ noble gas measurements secured with SAM and ongoing studies to optimize these measurements using the SAM testbed. References: [1] Farley, K.A.M Science Magazine, 342, (2013). [2] G. Kminek et al., Earth Planet Sc Lett 245, 1 (2006). [3] Dartnell, L.R., Biogeosciences 4, 545 (2007). [4] Pavlov, A. A., et al. Geophys Res Lett 39, 13202 (2012).

Radiofrequency Electromagnetic Radiation and Memory Performance: Sources of Uncertainty in Epidemiological Cohort Studies.

PubMed

Brzozek, Christopher; Benke, Kurt K; Zeleke, Berihun M; Abramson, Michael J; Benke, Geza

2018-03-26

Uncertainty in experimental studies of exposure to radiation from mobile phones has in the past only been framed within the context of statistical variability. It is now becoming more apparent to researchers that epistemic or reducible uncertainties can also affect the total error in results. These uncertainties are derived from a wide range of sources including human error, such as data transcription, model structure, measurement and linguistic errors in communication. The issue of epistemic uncertainty is reviewed and interpreted in the context of the MoRPhEUS, ExPOSURE and HERMES cohort studies which investigate the effect of radiofrequency electromagnetic radiation from mobile phones on memory performance. Research into this field has found inconsistent results due to limitations from a range of epistemic sources. Potential analytic approaches are suggested based on quantification of epistemic error using Monte Carlo simulation. It is recommended that future studies investigating the relationship between radiofrequency electromagnetic radiation and memory performance pay more attention to treatment of epistemic uncertainties as well as further research into improving exposure assessment. Use of directed acyclic graphs is also encouraged to display the assumed covariate relationship.

Radiofrequency Electromagnetic Radiation and Memory Performance: Sources of Uncertainty in Epidemiological Cohort Studies

PubMed Central

Zeleke, Berihun M.; Abramson, Michael J.; Benke, Geza

2018-01-01

Uncertainty in experimental studies of exposure to radiation from mobile phones has in the past only been framed within the context of statistical variability. It is now becoming more apparent to researchers that epistemic or reducible uncertainties can also affect the total error in results. These uncertainties are derived from a wide range of sources including human error, such as data transcription, model structure, measurement and linguistic errors in communication. The issue of epistemic uncertainty is reviewed and interpreted in the context of the MoRPhEUS, ExPOSURE and HERMES cohort studies which investigate the effect of radiofrequency electromagnetic radiation from mobile phones on memory performance. Research into this field has found inconsistent results due to limitations from a range of epistemic sources. Potential analytic approaches are suggested based on quantification of epistemic error using Monte Carlo simulation. It is recommended that future studies investigating the relationship between radiofrequency electromagnetic radiation and memory performance pay more attention to treatment of epistemic uncertainties as well as further research into improving exposure assessment. Use of directed acyclic graphs is also encouraged to display the assumed covariate relationship. PMID:29587425

Fruit Flies Provide New Insights in Low-Radiation Background Biology at the INFN Underground Gran Sasso National Laboratory (LNGS).

PubMed

Morciano, Patrizia; Cipressa, Francesca; Porrazzo, Antonella; Esposito, Giuseppe; Tabocchini, Maria Antonella; Cenci, Giovanni

2018-06-04

Deep underground laboratories (DULs) were originally created to host particle, astroparticle or nuclear physics experiments requiring a low-background environment with vastly reduced levels of cosmic-ray particle interference. More recently, the range of science projects requiring an underground experiment site has greatly expanded, thus leading to the recognition of DULs as truly multidisciplinary science sites that host important studies in several fields, including geology, geophysics, climate and environmental sciences, technology/instrumentation development and biology. So far, underground biology experiments are ongoing or planned in a few of the currently operating DULs. Among these DULs is the Gran Sasso National Laboratory (LNGS), where the majority of radiobiological data have been collected. Here we provide a summary of the current scenario of DULs around the world, as well as the specific features of the LNGS and a summary of the results we obtained so far, together with other findings collected in different underground laboratories. In particular, we focus on the recent results from our studies of Drosophila melanogaster, which provide the first evidence of the influence of the radiation environment on life span, fertility and response to genotoxic stress at the organism level. Given the increasing interest in this field and the establishment of new projects, it is possible that in the near future more DULs will serve as sites of radiobiology experiments, thus providing further relevant biological information at extremely low-dose-rate radiation. Underground experiments can be nicely complemented with above-ground studies at increasing dose rate. A systematic study performed in different exposure scenarios provides a potential opportunity to address important radiation protection questions, such as the dose/dose-rate relationship for cancer and non-cancer risk, the possible existence of dose/dose-rate threshold(s) for different biological systems and

New radiation protection calibration facility at CERN.

PubMed

Brugger, Markus; Carbonez, Pierre; Pozzi, Fabio; Silari, Marco; Vincke, Helmut

2014-10-01

The CERN radiation protection group has designed a new state-of-the-art calibration laboratory to replace the present facility, which is >20 y old. The new laboratory, presently under construction, will be equipped with neutron and gamma sources, as well as an X-ray generator and a beta irradiator. The present work describes the project to design the facility, including the facility placement criteria, the 'point-zero' measurements and the shielding study performed via FLUKA Monte Carlo simulations. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An Investigation of the Radiative Effects and Climate Feedbacks of Sea Ice Sources of Sea Salt Aerosol

NASA Astrophysics Data System (ADS)

Horowitz, H. M.; Alexander, B.; Bitz, C. M.; Jaegle, L.; Burrows, S. M.

2017-12-01

In polar regions, sea ice is a major source of sea salt aerosol through lofting of saline frost flowers or blowing saline snow from the sea ice surface. Under continued climate warming, an ice-free Arctic in summer with only first-year, more saline sea ice in winter is likely. Previous work has focused on climate impacts in summer from increasing open ocean sea salt aerosol emissions following complete sea ice loss in the Arctic, with conflicting results suggesting no net radiative effect or a negative climate feedback resulting from a strong first aerosol indirect effect. However, the radiative forcing from changes to the sea ice sources of sea salt aerosol in a future, warmer climate has not previously been explored. Understanding how sea ice loss affects the Arctic climate system requires investigating both open-ocean and sea ice sources of sea-salt aerosol and their potential interactions. Here, we implement a blowing snow source of sea salt aerosol into the Community Earth System Model (CESM) dynamically coupled to the latest version of the Los Alamos sea ice model (CICE5). Snow salinity is a key parameter affecting blowing snow sea salt emissions and previous work has assumed constant regional snow salinity over sea ice. We develop a parameterization for dynamic snow salinity in the sea ice model and examine how its spatial and temporal variability impacts the production of sea salt from blowing snow. We evaluate and constrain the snow salinity parameterization using available observations. Present-day coupled CESM-CICE5 simulations of sea salt aerosol concentrations including sea ice sources are evaluated against in situ and satellite (CALIOP) observations in polar regions. We then quantify the present-day radiative forcing from the addition of blowing snow sea salt aerosol with respect to aerosol-radiation and aerosol-cloud interactions. The relative contributions of sea ice vs. open ocean sources of sea salt aerosol to radiative forcing in polar regions is

Method and system for determining depth distribution of radiation-emitting material located in a source medium and radiation detector system for use therein

DOEpatents

Benke, Roland R.; Kearfott, Kimberlee J.; McGregor, Douglas S.

2003-03-04

A method, system and a radiation detector system for use therein are provided for determining the depth distribution of radiation-emitting material distributed in a source medium, such as a contaminated field, without the need to take samples, such as extensive soil samples, to determine the depth distribution. The system includes a portable detector assembly with an x-ray or gamma-ray detector having a detector axis for detecting the emitted radiation. The radiation may be naturally-emitted by the material, such as gamma-ray-emitting radionuclides, or emitted when the material is struck by other radiation. The assembly also includes a hollow collimator in which the detector is positioned. The collimator causes the emitted radiation to bend toward the detector as rays parallel to the detector axis of the detector. The collimator may be a hollow cylinder positioned so that its central axis is perpendicular to the upper surface of the large area source when positioned thereon. The collimator allows the detector to angularly sample the emitted radiation over many ranges of polar angles. This is done by forming the collimator as a single adjustable collimator or a set of collimator pieces having various possible configurations when connected together. In any one configuration, the collimator allows the detector to detect only the radiation emitted from a selected range of polar angles measured from the detector axis. Adjustment of the collimator or the detector therein enables the detector to detect radiation emitted from a different range of polar angles. The system further includes a signal processor for processing the signals from the detector wherein signals obtained from different ranges of polar angles are processed together to obtain a reconstruction of the radiation-emitting material as a function of depth, assuming, but not limited to, a spatially-uniform depth distribution of the material within each layer. The detector system includes detectors having

Investigating the source of near-relativistic and relativistic electrons in Earth's inner radiation belt

DOE PAGES

Turner, Drew Lawson; O'Brien, T. P.; Fennell, J. F.; ...

2017-01-30

Using observations from NASA's Van Allen Probes, we study the role of sudden particle enhancements at low L shells (SPELLS) as a source of inner radiation belt electrons. SPELLS events are characterized by electron intensity enhancements of approximately an order of magnitude or more in less than 1 day at L < 3. During quiet and average geomagnetic conditions, the phase space density radial distributions for fixed first and second adiabatic invariants are peaked at 2 < L < 3 for electrons ranging in energy from ~50 keV to ~1 MeV, indicating that slow inward radial diffusion is not themore » dominant source of inner belt electrons under quiet/average conditions. During SPELLS events, the evolution of electron distributions reveals an enhancement of phase space density that can exceed 3 orders of magnitude in the slot region and continues into the inner radiation belt, which is evidence that these events are an important—and potentially dominant—source of inner belt electrons. Electron fluxes from September 2012 through February 2016 reveal that SPELLS occur frequently (~2.5/month at 200 keV), but the number of observed events decreases exponentially with increasing electron energy for ≥100 keV. After SPELLS events, the slot region reforms due to slow energy-dependent decay over several day time scales, consistent with losses due to interactions with plasmaspheric hiss. Altogether, these results indicate that the peaked phase space density distributions in the inner electron radiation belt result from an “on/off,” geomagnetic-activity-dependent source from higher radial distances.« less

Investigating the source of near-relativistic and relativistic electrons in Earth's inner radiation belt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turner, Drew Lawson; O'Brien, T. P.; Fennell, J. F.

Using observations from NASA's Van Allen Probes, we study the role of sudden particle enhancements at low L shells (SPELLS) as a source of inner radiation belt electrons. SPELLS events are characterized by electron intensity enhancements of approximately an order of magnitude or more in less than 1 day at L < 3. During quiet and average geomagnetic conditions, the phase space density radial distributions for fixed first and second adiabatic invariants are peaked at 2 < L < 3 for electrons ranging in energy from ~50 keV to ~1 MeV, indicating that slow inward radial diffusion is not themore » dominant source of inner belt electrons under quiet/average conditions. During SPELLS events, the evolution of electron distributions reveals an enhancement of phase space density that can exceed 3 orders of magnitude in the slot region and continues into the inner radiation belt, which is evidence that these events are an important—and potentially dominant—source of inner belt electrons. Electron fluxes from September 2012 through February 2016 reveal that SPELLS occur frequently (~2.5/month at 200 keV), but the number of observed events decreases exponentially with increasing electron energy for ≥100 keV. After SPELLS events, the slot region reforms due to slow energy-dependent decay over several day time scales, consistent with losses due to interactions with plasmaspheric hiss. Altogether, these results indicate that the peaked phase space density distributions in the inner electron radiation belt result from an “on/off,” geomagnetic-activity-dependent source from higher radial distances.« less

The Idaho National Engineering and Environmental Laboratory Source Water Assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sehlke, G.

2003-03-17

The Idaho National Engineering and Environmental Laboratory (INEEL) covers approximately 890 square miles and includes 12 public water systems that must be evaluated for Source water protection purposes under the Safe Drinking Water Act. Because of its size and location, six watersheds and five aquifers could potentially affect the INEEL's drinking water sources. Based on a preliminary evaluation of the available information, it was determined that the Big Lost River, Birch Creek, and Little Lost River Watersheds and the eastern Snake River Plain Aquifer needed to be assessed. These watersheds were delineated using the United States Geologic Survey's Hydrological Unitmore » scheme. Well capture zones were originally estimated using the RESSQC module of the Environmental Protection Agency's Well Head Protection Area model, and the initial modeling assumptions and results were checked by running several scenarios using Modflow modeling. After a technical review, the resulting capture zones were expanded to account for the uncertainties associated with changing groundwater flow directions, a this vadose zone, and other data uncertainties. Finally, all well capture zones at a given facility were merged to a single wellhead protection area at each facility. A contaminant source inventory was conducted, and the results were integrated with the well capture zones, watershed and aquifer information, and facility information using geographic information system technology to complete the INEEL's Source Water Assessment. Of the INEEL's 12 public water systems, three systems rated as low susceptibility (EBR-1, Main Gate, and Gun Range), and the remainder rated as moderate susceptibility. No INEEL public water system rated as high susceptibility. We are using this information to develop a source water management plan from which we will subsequently implement an INEEL-wide source water management program. The results are a very robust set of wellhead protection areas that will

Laboratory Plasma Source as an MHD Model for Astrophysical Jets

NASA Technical Reports Server (NTRS)

Mayo, Robert M.

1997-01-01

The significance of the work described herein lies in the demonstration of Magnetized Coaxial Plasma Gun (MCG) devices like CPS-1 to produce energetic laboratory magneto-flows with embedded magnetic fields that can be used as a simulation tool to study flow interaction dynamic of jet flows, to demonstrate the magnetic acceleration and collimation of flows with primarily toroidal fields, and study cross field transport in turbulent accreting flows. Since plasma produced in MCG devices have magnetic topology and MHD flow regime similarity to stellar and extragalactic jets, we expect that careful investigation of these flows in the laboratory will reveal fundamental physical mechanisms influencing astrophysical flows. Discussion in the next section (sec.2) focuses on recent results describing collimation, leading flow surface interaction layers, and turbulent accretion. The primary objectives for a new three year effort would involve the development and deployment of novel electrostatic, magnetic, and visible plasma diagnostic techniques to measure plasma and flow parameters of the CPS-1 device in the flow chamber downstream of the plasma source to study, (1) mass ejection, morphology, and collimation and stability of energetic outflows, (2) the effects of external magnetization on collimation and stability, (3) the interaction of such flows with background neutral gas, the generation of visible emission in such interaction, and effect of neutral clouds on jet flow dynamics, and (4) the cross magnetic field transport of turbulent accreting flows. The applicability of existing laboratory plasma facilities to the study of stellar and extragalactic plasma should be exploited to elucidate underlying physical mechanisms that cannot be ascertained though astrophysical observation, and provide baseline to a wide variety of proposed models, MHD and otherwise. The work proposed herin represents a continued effort on a novel approach in relating laboratory experiments to

Situational awareness of hazards: Validation of multi-source radiation measurements

NASA Astrophysics Data System (ADS)

Hultquist, C.; Cervone, G.

2016-12-01

Citizen-led movements producing scientific hazard data during disasters are increasingly common. After the Japanese earthquake-triggered tsunami in 2011, and the resulting radioactive releases at the damaged Fukushima Daiichi nuclear power plants, citizens monitored on-ground levels of radiation with innovative mobile devices built from off-the-shelf components. To date, the citizen-led SAFECAST project has recorded 50 million radiation measurements worldwide, with the majority of these measurements from Japan. The analysis of data which are multi-dimensional, not vetted, and provided from multiple devices presents big data challenges due to their volume, velocity, variety, and veracity. While the SAFECAST project produced massive open-source radiation measurements at specific coordinates and times, the reliability and validity of the overall data have not yet been assessed. The nuclear disaster provides a case for assessing the SAFECAST data with official aerial remote sensing radiation data jointly collected by the governments of the United States and Japan. A spatial and statistical assessment of SAFECAST requires several preprocessing steps. First, SAFECAST ionized radiation sensors collected data using different units of measure than the government data, and they had to be converted. Secondly, the normally occurring radiation and decay rates of Cesium from deposition surveys were used to properly compare measurements in space and time. Finally, the GPS located points were selected within overlapping extents at multiple spatial resolutions. Quantitative measures were used to assess the similarity and differences in the observed measurements. Radiation measurements from the same geographic extents show similar spatial variations and statistically significant correlations. The results suggest that actionable scientific data for disasters and emergencies can be inferred from non-traditional and not vetted data generated through citizen science projects. This

Global source attribution of sulfate aerosol and its radiative forcing

NASA Astrophysics Data System (ADS)

Yang, Y.; Wang, H.; Smith, S.; Easter, R. C.; Ma, P. L.; Qian, Y.; Li, C.; Yu, H.; Rasch, P. J.

2017-12-01

Sulfate is an important aerosol that poses health risks and influences climate. Due to long-range atmospheric transport, local sulfate pollution could result from intercontinental influences, making domestic efforts of improving air quality inefficient. Accurate understanding of source attribution of sulfate and its radiative forcing is important for both regional air quality improvement and global climate mitigation. In this study, for the first time, a sulfur source-tagging capability is implemented in the Community Atmosphere Model (CAM5) to quantify the global source-receptor relationships of sulfate and its direct and indirect radiative forcing (DRF and IRF). Near-surface sulfate concentrations are mostly contributed by local emissions in regions with high emissions, while over regions with relatively low SO2 emissions, the near-surface sulfate is primarily attributed to non-local sources from long-range transport. The export of SO2 and sulfate from Europe contributes 20% of sulfate concentrations over North Africa, Russia and Central Asia. Sources from the Middle East account for 20% of sulfate over North Africa, Southern Africa and Central Asia in winter and autumn, and 20% over South Asia in spring. East Asia accounts for about 50% of sulfate over Southeast Asia in winter and autumn, 15% over Russia in summer, and 10% over North America in spring. South Asia contributes to 25% of sulfate over Southeast Asia in spring. Lifetime of aerosols, together with regional export, is found to determine regional air quality. The simulated global total sulfate DRF is -0.42 W m-2, with 75% contributed by anthropogenic sulfate and 25% contributed by natural sulfate. In the Southern Hemisphere tropics, dimethyl sulfide (DMS) contributes the most to the total DRF. East Asia has the largest contribution of 20-30% over the Northern Hemisphere mid- and high-latitudes. A 20% perturbation of sulfate and its precursor emissions gives a sulfate IRF of -0.44 W m-2. DMS has the

Generalized source Finite Volume Method for radiative transfer equation in participating media

NASA Astrophysics Data System (ADS)

Zhang, Biao; Xu, Chuan-Long; Wang, Shi-Min

2017-03-01

Temperature monitoring is very important in a combustion system. In recent years, non-intrusive temperature reconstruction has been explored intensively on the basis of calculating arbitrary directional radiative intensities. In this paper, a new method named Generalized Source Finite Volume Method (GSFVM) was proposed. It was based on radiative transfer equation and Finite Volume Method (FVM). This method can be used to calculate arbitrary directional radiative intensities and is proven to be accurate and efficient. To verify the performance of this method, six test cases of 1D, 2D, and 3D radiative transfer problems were investigated. The numerical results show that the efficiency of this method is close to the radial basis function interpolation method, but the accuracy and stability is higher than that of the interpolation method. The accuracy of the GSFVM is similar to that of the Backward Monte Carlo (BMC) algorithm, while the time required by the GSFVM is much shorter than that of the BMC algorithm. Therefore, the GSFVM can be used in temperature reconstruction and improvement on the accuracy of the FVM.

ENHANCED BIOREMEDIATION UTILIZING HYDROGEN PEROXIDE AS A SUPPLEMENTAL SOURCE OF OXYGEN: A LABORATORY AND FIELD STUDY

EPA Science Inventory

Laboratory and field scale studies were conducted to investigate the feasibility of using hydrogen peroxide as a supplemental source of oxygen for bioremediation of an aviation gasoline fuel spill. Field samples of aviation gasoline contaminated aquifer material were artificially...

Radiation Assessment Detector for Mars Science Laboratory

NASA Image and Video Library

2010-11-09

The Radiation Assessment Detector, shown prior to its September 2010 installation onto NASA Mars rover Curiosity, will aid future human missions to Mars by providing information about the radiation environment on Mars and on the way to Mars.

Use of the NASA Space Radiation Laboratory at Brookhaven National Laboratory to Conduct Charged Particle Radiobiology Studies Relevant to Ion Therapy

PubMed Central

Held, Kathryn D.; Blakely, Eleanor A.; Story, Michael D.; Lowenstein, Derek I.

2016-01-01

Although clinical studies with carbon ions have been conducted successfully in Japan and Europe, the limited radiobiological information about charged particles that are heavier than protons remains a significant impediment to exploiting the full potential of particle therapy. There is growing interest in the U.S. to build a cancer treatment facility that utilizes charged particles heavier than protons. Therefore, it is essential that additional radiobiological knowledge be obtained using state-of-the-art technologies and biological models and end points relevant to clinical outcome. Currently, most such ion radiotherapy-related research is being conducted outside the U.S. This article addresses the substantial contributions to that research that are possible at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), which is the only facility in the U.S. at this time where heavy-ion radiobiology research with the ion species and energies of interest for therapy can be done. Here, we briefly discuss the relevant facilities at NSRL and how selected charged particle biology research gaps could be addressed using those facilities. PMID:27195609

Use of the NASA Space Radiation Laboratory at Brookhaven National Laboratory to Conduct Charged Particle Radiobiology Studies Relevant to Ion Therapy.

PubMed

Held, Kathryn D; Blakely, Eleanor A; Story, Michael D; Lowenstein, Derek I

2016-06-01

Although clinical studies with carbon ions have been conducted successfully in Japan and Europe, the limited radiobiological information about charged particles that are heavier than protons remains a significant impediment to exploiting the full potential of particle therapy. There is growing interest in the U.S. to build a cancer treatment facility that utilizes charged particles heavier than protons. Therefore, it is essential that additional radiobiological knowledge be obtained using state-of-the-art technologies and biological models and end points relevant to clinical outcome. Currently, most such ion radiotherapy-related research is being conducted outside the U.S. This article addresses the substantial contributions to that research that are possible at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), which is the only facility in the U.S. at this time where heavy-ion radiobiology research with the ion species and energies of interest for therapy can be done. Here, we briefly discuss the relevant facilities at NSRL and how selected charged particle biology research gaps could be addressed using those facilities.

Earthquake source properties from pseudotachylite

USGS Publications Warehouse

Beeler, Nicholas M.; Di Toro, Giulio; Nielsen, Stefan

2016-01-01

The motions radiated from an earthquake contain information that can be interpreted as displacements within the source and therefore related to stress drop. Except in a few notable cases, the source displacements can neither be easily related to the absolute stress level or fault strength, nor attributed to a particular physical mechanism. In contrast paleo-earthquakes recorded by exhumed pseudotachylite have a known dynamic mechanism whose properties constrain the co-seismic fault strength. Pseudotachylite can also be used to directly address a longstanding discrepancy between seismologically measured static stress drops, which are typically a few MPa, and much larger dynamic stress drops expected from thermal weakening during localized slip at seismic speeds in crystalline rock [Sibson, 1973; McKenzie and Brune, 1969; Lachenbruch, 1980; Mase and Smith, 1986; Rice, 2006] as have been observed recently in laboratory experiments at high slip rates [Di Toro et al., 2006a]. This note places pseudotachylite-derived estimates of fault strength and inferred stress levels within the context and broader bounds of naturally observed earthquake source parameters: apparent stress, stress drop, and overshoot, including consideration of roughness of the fault surface, off-fault damage, fracture energy, and the 'strength excess'. The analysis, which assumes stress drop is related to corner frequency by the Madariaga [1976] source model, is restricted to the intermediate sized earthquakes of the Gole Larghe fault zone in the Italian Alps where the dynamic shear strength is well-constrained by field and laboratory measurements. We find that radiated energy exceeds the shear-generated heat and that the maximum strength excess is ~16 MPa. More generally these events have inferred earthquake source parameters that are rate, for instance a few percent of the global earthquake population has stress drops as large, unless: fracture energy is routinely greater than existing models allow

Efficacy and safety of far infrared radiation in lymphedema treatment: clinical evaluation and laboratory analysis.

PubMed

Li, Ke; Zhang, Zheng; Liu, Ning Fei; Feng, Shao Qing; Tong, Yun; Zhang, Ju Fang; Constantinides, Joannis; Lazzeri, Davide; Grassetti, Luca; Nicoli, Fabio; Zhang, Yi Xin

2017-04-01

Swelling is the most common symptom of extremities lymphedema. Clinical evaluation and laboratory analysis were conducted after far infrared radiation (FIR) treatment on the main four components of lymphedema: fluid, fat, protein, and hyaluronan. Far infrared radiation is a kind of hyperthermia therapy with several and additional benefits as well as promoting microcirculation flow and improving collateral lymph circumfluence. Although FIR therapy has been applied for several years on thousands of lymphedema patients, there are still few studies that have reported the biological effects of FIR on lymphatic tissue. In this research, we investigate the effects of far infrared rays on the major components of lymphatic tissue. Then, we explore the effectiveness and safety of FIR as a promising treatment modality of lymphedema. A total of 32 patients affected by lymphedema in stage II and III were treated between January 2015 and January 2016 at our department. After therapy, a significant decrease of limb circumference measurements was noted and improving of quality of life was registered. Laboratory examination showed the treatment can also decrease the deposition of fluid, fat, hyaluronan, and protein, improving the swelling condition. We believe FIR treatment could be considered as both an alternative monotherapy and a useful adjunctive to the conservative or surgical lymphedema procedures. Furthermore, the real and significant biological effects of FIR represent possible future applications in wide range of the medical field.

Modeling Laboratory Astrophysics Experiments in the High-Energy-Density Regime Using the CRASH Radiation-Hydrodynamics Model

NASA Astrophysics Data System (ADS)

Grosskopf, M. J.; Drake, R. P.; Trantham, M. R.; Kuranz, C. C.; Keiter, P. A.; Rutter, E. M.; Sweeney, R. M.; Malamud, G.

2012-10-01

The radiation hydrodynamics code developed by the Center for Radiative Shock Hydrodynamics (CRASH) at the University of Michigan has been used to model experimental designs for high-energy-density physics campaigns on OMEGA and other high-energy laser facilities. This code is an Eulerian, block-adaptive AMR hydrodynamics code with implicit multigroup radiation transport and electron heat conduction. CRASH model results have shown good agreement with a experimental results from a variety of applications, including: radiative shock, Kelvin-Helmholtz and Rayleigh-Taylor experiments on the OMEGA laser; as well as laser-driven ablative plumes in experiments by the Astrophysical Collisionless Shocks Experiments with Lasers (ACSEL), collaboration. We report a series of results with the CRASH code in support of design work for upcoming high-energy-density physics experiments, as well as comparison between existing experimental data and simulation results. This work is funded by the Predictive Sciences Academic Alliances Program in NNSA-ASC via grant DEFC52- 08NA28616, by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-FG52-09NA29548, and by the National Laser User Facility Program, grant number DE-NA0000850.

Radiation Environment of Phobos

NASA Astrophysics Data System (ADS)

Cooper, John F.; Clark, John H.; Sturner, Steven J.; Stubbs, Timothy; Wang, Yongli; Glenar, David A.; Schwadron, Nathan A.; Joyce, Colin J.; Spence, Harlan E.; Farrell, William M.

2017-10-01

The innermost Martian moon Phobos is a potential way station for the human exploration of Mars and the solar system beyond the orbit of Mars. It has a similar radiation environment to that at 1 AU for hot plasma and more energetic particles from solar, heliospheric and galactic sources. In the past two decades there have been many spacecraft measurements at 1 AU, and occasionally in the Mars orbital region around the Sun, that can be used to define a reference model for the time-averaged and time-variable radiation environments at Mars and Phobos. Yearly to hourly variance comes from the eleven-year solar activity cycle and its impact on solar energetic, heliospheric, and solar-modulated galactic cosmic ray particles. We report progress on compilation of the reference model from U.S. and international spacecraft data sources of the NASA Space Physics Data Facility and the Virtual Energetic Particle Observatory (VEPO), and from tissue-equivalent dosage rate measurements by the CRaTER instrument on the Lunar Reconnaissance Observer spacecraft now in lunar orbit. Similar dosage rate data are also available from the Mars surface via the NASA Planetary Data System archive from the Radiation Assessment Detector (RAD) instrument aboard the Mars Science Laboratory (MSL) Curiosity rover. The sub-Mars surface hemisphere of Phobos is slightly blocked from energetic particle irradiation by the body of Mars but there is a greater global variance of interplanetary radiation exposure as we have calculated from the known topography of this irregularly shaped moon. Phobos receives a relatively small flux of secondary radiation from galactic cosmic ray interactions with the Mars surface and atmosphere, and at plasma energies from pickup ions escaping out of the Mars atmosphere. The greater secondary radiation source is from cosmic ray interactions with the moon surface, which we have simulated with the GEANT radiation transport code for various cases of the surface regolith

Intensity-Modulated Advanced X-ray Source (IMAXS) for Homeland Security Applications

NASA Astrophysics Data System (ADS)

Langeveld, Willem G. J.; Johnson, William A.; Owen, Roger D.; Schonberg, Russell G.

2009-03-01

X-ray cargo inspection systems for the detection and verification of threats and contraband require high x-ray energy and high x-ray intensity to penetrate dense cargo. On the other hand, low intensity is desirable to minimize the radiation footprint. A collaboration between HESCO/PTSE Inc., Schonberg Research Corporation and Rapiscan Laboratories, Inc. has been formed in order to design and build an Intensity-Modulated Advanced X-ray Source (IMAXS). Such a source would allow cargo inspection systems to achieve up to two inches greater imaging penetration capability, while retaining the same average radiation footprint as present fixed-intensity sources. Alternatively, the same penetration capability can be obtained as with conventional sources with a reduction of the average radiation footprint by about a factor of three. The key idea is to change the intensity of the source for each x-ray pulse based on the signal strengths in the inspection system detector array during the previous pulse. In this paper we describe methods to accomplish pulse-to-pulse intensity modulation in both S-band (2998 MHz) and X-band (9303 MHz) linac sources, with diode or triode (gridded) electron guns. The feasibility of these methods has been demonstrated. Additionally, we describe a study of a shielding design that would allow a 6 MV X-band source to be used in mobile applications.

Open-source software for collision detection in external beam radiation therapy

NASA Astrophysics Data System (ADS)

Suriyakumar, Vinith M.; Xu, Renee; Pinter, Csaba; Fichtinger, Gabor

2017-03-01

PURPOSE: Collision detection for external beam radiation therapy (RT) is important for eliminating the need for dryruns that aim to ensure patient safety. Commercial treatment planning systems (TPS) offer this feature but they are expensive and proprietary. Cobalt-60 RT machines are a viable solution to RT practice in low-budget scenarios. However, such clinics are hesitant to invest in these machines due to a lack of affordable treatment planning software. We propose the creation of an open-source room's eye view visualization module with automated collision detection as part of the development of an open-source TPS. METHODS: An openly accessible linac 3D geometry model is sliced into the different components of the treatment machine. The model's movements are based on the International Electrotechnical Commission standard. Automated collision detection is implemented between the treatment machine's components. RESULTS: The room's eye view module was built in C++ as part of SlicerRT, an RT research toolkit built on 3D Slicer. The module was tested using head and neck and prostate RT plans. These tests verified that the module accurately modeled the movements of the treatment machine and radiation beam. Automated collision detection was verified using tests where geometric parameters of the machine's components were changed, demonstrating accurate collision detection. CONCLUSION: Room's eye view visualization and automated collision detection are essential in a Cobalt-60 treatment planning system. Development of these features will advance the creation of an open-source TPS that will potentially help increase the feasibility of adopting Cobalt-60 RT.

Baobab Laboratory Information Management System: Development of an Open-Source Laboratory Information Management System for Biobanking.

PubMed

Bendou, Hocine; Sizani, Lunga; Reid, Tim; Swanepoel, Carmen; Ademuyiwa, Toluwaleke; Merino-Martinez, Roxana; Meuller, Heimo; Abayomi, Akin; Christoffels, Alan

2017-04-01

A laboratory information management system (LIMS) is central to the informatics infrastructure that underlies biobanking activities. To date, a wide range of commercial and open-source LIMSs are available and the decision to opt for one LIMS over another is often influenced by the needs of the biobank clients and researchers, as well as available financial resources. The Baobab LIMS was developed by customizing the Bika LIMS software ( www.bikalims.org ) to meet the requirements of biobanking best practices. The need to implement biobank standard operation procedures as well as stimulate the use of standards for biobank data representation motivated the implementation of Baobab LIMS, an open-source LIMS for Biobanking. Baobab LIMS comprises modules for biospecimen kit assembly, shipping of biospecimen kits, storage management, analysis requests, reporting, and invoicing. The Baobab LIMS is based on the Plone web-content management framework. All the system requirements for Plone are applicable to Baobab LIMS, including the need for a server with at least 8 GB RAM and 120 GB hard disk space. Baobab LIMS is a server-client-based system, whereby the end user is able to access the system securely through the internet on a standard web browser, thereby eliminating the need for standalone installations on all machines.

Baobab Laboratory Information Management System: Development of an Open-Source Laboratory Information Management System for Biobanking

PubMed Central

Bendou, Hocine; Sizani, Lunga; Reid, Tim; Swanepoel, Carmen; Ademuyiwa, Toluwaleke; Merino-Martinez, Roxana; Meuller, Heimo; Abayomi, Akin

2017-01-01

A laboratory information management system (LIMS) is central to the informatics infrastructure that underlies biobanking activities. To date, a wide range of commercial and open-source LIMSs are available and the decision to opt for one LIMS over another is often influenced by the needs of the biobank clients and researchers, as well as available financial resources. The Baobab LIMS was developed by customizing the Bika LIMS software (www.bikalims.org) to meet the requirements of biobanking best practices. The need to implement biobank standard operation procedures as well as stimulate the use of standards for biobank data representation motivated the implementation of Baobab LIMS, an open-source LIMS for Biobanking. Baobab LIMS comprises modules for biospecimen kit assembly, shipping of biospecimen kits, storage management, analysis requests, reporting, and invoicing. The Baobab LIMS is based on the Plone web-content management framework. All the system requirements for Plone are applicable to Baobab LIMS, including the need for a server with at least 8 GB RAM and 120 GB hard disk space. Baobab LIMS is a server–client-based system, whereby the end user is able to access the system securely through the internet on a standard web browser, thereby eliminating the need for standalone installations on all machines. PMID:28375759

6th international conference on biophysics and synchrotron radiation. Program/Abstracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pittroff, Connie; Strasser, Susan Barr

1999-08-03

This STI product consists of the Program/Abstracts book that was prepared for the participants in the Sixth International Conference on Biophysics and Synchrotron Radiation that was held August 4-8, 1998, at the Advanced Photon Source, Argonne National Laboratory. This book contains the full conference program and abstracts of the scientific presentations.

Blind separation of incoherent and spatially disjoint sound sources

NASA Astrophysics Data System (ADS)

Dong, Bin; Antoni, Jérôme; Pereira, Antonio; Kellermann, Walter

2016-11-01

Blind separation of sound sources aims at reconstructing the individual sources which contribute to the overall radiation of an acoustical field. The challenge is to reach this goal using distant measurements when all sources are operating concurrently. The working assumption is usually that the sources of interest are incoherent - i.e. statistically orthogonal - so that their separation can be approached by decorrelating a set of simultaneous measurements, which amounts to diagonalizing the cross-spectral matrix. Principal Component Analysis (PCA) is traditionally used to this end. This paper reports two new findings in this context. First, a sufficient condition is established under which "virtual" sources returned by PCA coincide with true sources; it stipulates that the sources of interest should be not only incoherent but also spatially orthogonal. A particular case of this instance is met by spatially disjoint sources - i.e. with non-overlapping support sets. Second, based on this finding, a criterion that enforces both statistical and spatial orthogonality is proposed to blindly separate incoherent sound sources which radiate from disjoint domains. This criterion can be easily incorporated into acoustic imaging algorithms such as beamforming or acoustical holography to identify sound sources of different origins. The proposed methodology is validated on laboratory experiments. In particular, the separation of aeroacoustic sources is demonstrated in a wind tunnel.

Investigation on Main Radiation Source at Operation Floor of Fukushima Daiichi Nuclear Power Station Unit 4

NASA Astrophysics Data System (ADS)

Hirayama, Hideo; Kondo, Kenjiro; Suzuki, Seishiro; Hamamoto, Shimpei; Iwanaga, Kohei

2017-09-01

Pulse height distributions were measured using a LaBr3 detector set in a 1 cm lead collimator to investigate main radiation source at the operation floor of Fukushima Daiichi Nuclear Power Station Unit 4. It was confirmed that main radiation source above the reactor well was Co-60 from the activated steam dryer in the DS pool (Dryer-Separator pool) and that at the standby area was Cs-134 and Cs-137 from contaminated buildings and debris at the lower floor. Full energy peak count rate of Co-60 was reduced about 1/3 by 12mm lead sheet placed on the floor of the fuel handling machine.

Nonlinear Gravitational and Radiation Aspects in Nanoliquid with Exponential Space Dependent Heat Source and Variable Viscosity

NASA Astrophysics Data System (ADS)

Gireesha, B. J.; Kumar, P. B. Sampath; Mahanthesh, B.; Shehzad, S. A.; Abbasi, F. M.

2018-05-01

The nonlinear convective flow of kerosene-Alumina nanoliquid subjected to an exponential space dependent heat source and temperature dependent viscosity is investigated here. This study is focuses on augmentation of heat transport rate in liquid propellant rocket engine. The kerosene-Alumina nanoliquid is considered as the regenerative coolant. Aspects of radiation and viscous dissipation are also covered. Relevant nonlinear system is solved numerically via RK based shooting scheme. Diverse flow fields are computed and examined for distinct governing variables. We figured out that the nanoliquid's temperature increased due to space dependent heat source and radiation aspects. The heat transfer rate is higher in case of changeable viscosity than constant viscosity.

Nonlinear Gravitational and Radiation Aspects in Nanoliquid with Exponential Space Dependent Heat Source and Variable Viscosity

NASA Astrophysics Data System (ADS)

Gireesha, B. J.; Kumar, P. B. Sampath; Mahanthesh, B.; Shehzad, S. A.; Abbasi, F. M.

2018-02-01

The nonlinear convective flow of kerosene-Alumina nanoliquid subjected to an exponential space dependent heat source and temperature dependent viscosity is investigated here. This study is focuses on augmentation of heat transport rate in liquid propellant rocket engine. The kerosene-Alumina nanoliquid is considered as the regenerative coolant. Aspects of radiation and viscous dissipation are also covered. Relevant nonlinear system is solved numerically via RK based shooting scheme. Diverse flow fields are computed and examined for distinct governing variables. We figured out that the nanoliquid's temperature increased due to space dependent heat source and radiation aspects. The heat transfer rate is higher in case of changeable viscosity than constant viscosity.

Entangled γ-photons—classical laboratory exercise with modern detectors

NASA Astrophysics Data System (ADS)

Hetfleiš, Jakub; Lněnička, Jindřich; Šlégr, Jan

2018-03-01

This paper describes the application of modern semiconductor detectors of γ and β radiation, which can be used in undergraduate laboratory experiments and lecture demonstrations as a replacement for Geiger-Müller (GM) tubes. Unlike GM tubes, semiconductor detectors do not require a high voltage power source or shaping circuits. The principle of operation of semiconductor detectors is discussed briefly, and classical experiments from nuclear physics are described, ranging from the measurements of linear and mass attenuation coefficient to a demonstration of entangled γ-photons.

RADIATION FROM ELECTRON PHASE SPACE HOLES AS A POSSIBLE SOURCE OF JOVIAN S-BURSTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goodrich, K. A.; Ergun, R. E., E-mail: katherine.goodrich@lasp.colorado.edu

2015-08-10

Radio-frequency short burst emissions (10–40 MHz), known as Jovian S-bursts, have been observed from the Jovian aurora for over fifty years. These emissions, associated with Io’s motion, have a rapidly declining frequency and an exceptionally narrow bandwidth. While it is widely believed that S-bursts are generated by the electron cyclotron maser instability, the mechanism responsible for the rapidly declining frequency and narrow bandwidth currently is not well established. We explore a hypothesis that electron phase space holes radiate or stimulate radiation in the Jovian aurora plasma environment as a possible source of S-burst emissions. Electron phase-space holes (EHs) are ubiquitousmore » in an auroral environment and travel at the implied speeds (∼20,000 km s{sup −1}) of the structures creating the Jovian S-bursts. Furthermore, EHs have the proper physical size to create the observed bandwidth, have sufficient energy content, and can create an environment whereby X mode emissions can be excited. If verified, these findings imply that EHs may be an important source of radiation from strongly magnetized or relativistic astrophysical plasmas.« less

LIGHT SOURCE: Physical design of a 10 MeV LINAC for polymer radiation processing

NASA Astrophysics Data System (ADS)

Feng, Guang-Yao; Pei, Yuan-Ji; Wang, Lin; Zhang, Shan-Cai; Wu, Cong-Feng; Jin, Kai; Li, Wei-Min

2009-06-01

In China, polymer radiation processing has become one of the most important processing industries. The radiation processing source may be an electron beam accelerator or a radioactive source. Physical design of an electron beam facility applied for radiation crosslinking is introduced in this paper because of it's much higher dose rate and efficiency. Main part of this facility is a 10 MeV travelling wave electron linac with constant impedance accelerating structure. A start to end simulation concerning the linac is reported in this paper. The codes Opera-3d, Poisson-superfish and Parmela are used to describe electromagnetic elements of the accelerator and track particle distribution from the cathode to the end of the linac. After beam dynamic optimization, wave phase velocities in the structure have been chosen to be 0.56, 0.9 and 0.999 respectively. Physical parameters about the main elements such as DC electron gun, iris-loaded periodic structure, solenoids, etc, are presented. Simulation results proves that it can satisfy the industrial requirement. The linac is under construction. Some components have been finished. Measurements proved that they are in a good agreement with the design values.

Adaptors for radiation detectors

DOEpatents

Livesay, Ronald Jason

2014-04-22

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.

Adaptors for radiation detectors

DOEpatents

Livesay, Ronald Jason

2015-07-28

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.

Performance on the low charge state laser ion source in BNL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okamura, M.; Alessi, J.; Beebe, E.

On March 2014, a Laser Ion Source (LIS) was commissioned which delivers high-brightness, low-charge-state heavy ions for the hadron accelerator complex in Brookhaven National Laboratory (BNL). Since then, the LIS has provided many heavy ion species successfully. The low-charge-state (mostly singly charged) beams are injected to the Electron Beam Ion Source (EBIS), where ions are then highly ionized to fit to the following accelerator’s Q/M acceptance, like Au 32+. Recently we upgraded the LIS to be able to provide two different beams into EBIS on a pulse-to-pulse basis. Now the LIS is simultaneously providing beams for both the Relativistic Heavymore » Ion Collider (RHIC) and NASA Space Radiation Laboratory (NSRL).« less

Design study of primary ion provider for relativistic heavy ion collider electron beam ion source.

PubMed

Kondo, K; Kanesue, T; Tamura, J; Okamura, M

2010-02-01

Brookhaven National Laboratory has developed the new preinjector system, electron beam ion source (EBIS) for relativistic heavy ion collider (RHIC) and National Aeronautics and Space Administration Space Radiation Laboratory. Design of primary ion provider is an essential problem since it is required to supply beams with different ion species to multiple users simultaneously. The laser ion source with a defocused laser can provide a low charge state and low emittance ion beam, and is a candidate for the primary ion source for RHIC-EBIS. We show a suitable design with appropriate drift length and solenoid, which helps to keep sufficient total charge number with longer pulse length. The whole design of primary ion source, as well as optics arrangement, solid targets configuration and heating about target, is presented.

Recycling of laser and plasma radiation energy for enhancement of extreme ultraviolet sources for nanolithography

NASA Astrophysics Data System (ADS)

Sizyuk, V.; Sizyuk, T.; Hassanein, A.; Johnson, K.

2018-01-01

We have developed comprehensive integrated models for detailed simulation of laser-produced plasma (LPP) and laser/target interaction, with potential recycling of the escaping laser and out-of-band plasma radiation. Recycling, i.e., returning the escaping laser and plasma radiation to the extreme ultraviolet (EUV) generation region using retroreflective mirrors, has the potential of increasing the EUV conversion efficiency (CE) by up to 60% according to our simulations. This would result in significantly reduced power consumption and/or increased EUV output. Based on our recently developed models, our High Energy Interaction with General Heterogeneous Target Systems (HEIGHTS) computer simulation package was upgraded for LPP devices to include various radiation recycling regimes and to estimate the potential CE enhancement. The upgraded HEIGHTS was used to study recycling of both laser and plasma-generated radiation and to predict possible gains in conversion efficiency compared to no-recycling LPP devices when using droplets of tin target. We considered three versions of the LPP system including a single CO2 laser, a single Nd:YAG laser, and a dual-pulse device combining both laser systems. The gains in generating EUV energy were predicted and compared for these systems. Overall, laser and radiation energy recycling showed the potential for significant enhancement in source efficiency of up to 60% for the dual-pulse system. Significantly higher CE gains might be possible with optimization of the pre-pulse and main pulse parameters and source size.

Development of a hemispherical rotational modulation collimator system for imaging spatial distribution of radiation sources

NASA Astrophysics Data System (ADS)

Na, M.; Lee, S.; Kim, G.; Kim, H. S.; Rho, J.; Ok, J. G.

2017-12-01

Detecting and mapping the spatial distribution of radioactive materials is of great importance for environmental and security issues. We design and present a novel hemispherical rotational modulation collimator (H-RMC) system which can visualize the location of the radiation source by collecting signals from incident rays that go through collimator masks. The H-RMC system comprises a servo motor-controlled rotating module and a hollow heavy-metallic hemisphere with slits/slats equally spaced with the same angle subtended from the main axis. In addition, we also designed an auxiliary instrument to test the imaging performance of the H-RMC system, comprising a high-precision x- and y-axis staging station on which one can mount radiation sources of various shapes. We fabricated the H-RMC system which can be operated in a fully-automated fashion through the computer-based controller, and verify the accuracy and reproducibility of the system by measuring the rotational and linear positions with respect to the programmed values. Our H-RMC system may provide a pivotal tool for spatial radiation imaging with high reliability and accuracy.

Performance of viruses and bacteriophages for fecal source determination in a multi-laboratory, comparative study.

PubMed

Harwood, Valerie J; Boehm, Alexandria B; Sassoubre, Lauren M; Vijayavel, Kannappan; Stewart, Jill R; Fong, Theng-Theng; Caprais, Marie-Paule; Converse, Reagan R; Diston, David; Ebdon, James; Fuhrman, Jed A; Gourmelon, Michele; Gentry-Shields, Jennifer; Griffith, John F; Kashian, Donna R; Noble, Rachel T; Taylor, Huw; Wicki, Melanie

2013-11-15

An inter-laboratory study of the accuracy of microbial source tracking (MST) methods was conducted using challenge fecal and sewage samples that were spiked into artificial freshwater and provided as unknowns (blind test samples) to the laboratories. The results of the Source Identification Protocol Project (SIPP) are presented in a series of papers that cover 41 MST methods. This contribution details the results of the virus and bacteriophage methods targeting human fecal or sewage contamination. Human viruses used as source identifiers included adenoviruses (HAdV), enteroviruses (EV), norovirus Groups I and II (NoVI and NoVII), and polyomaviruses (HPyVs). Bacteriophages were also employed, including somatic coliphages and F-specific RNA bacteriophages (FRNAPH) as general indicators of fecal contamination. Bacteriophage methods targeting human fecal sources included genotyping of FRNAPH isolates and plaque formation on bacterial hosts Enterococcus faecium MB-55, Bacteroides HB-73 and Bacteroides GB-124. The use of small sample volumes (≤50 ml) resulted in relatively insensitive theoretical limits of detection (10-50 gene copies or plaques × 50 ml(-1)) which, coupled with low virus concentrations in samples, resulted in high false-negative rates, low sensitivity, and low negative predictive values. On the other hand, the specificity of the human virus methods was generally close to 100% and positive predictive values were ∼40-70% with the exception of NoVs, which were not detected. The bacteriophage methods were generally much less specific toward human sewage than virus methods, although FRNAPH II genotyping was relatively successful, with 18% sensitivity and 85% specificity. While the specificity of the human virus methods engenders great confidence in a positive result, better concentration methods and larger sample volumes must be utilized for greater accuracy of negative results, i.e. the prediction that a human contamination source is absent. Copyright �

A New Electron Source for Laboratory Simulation of the Space Environment

NASA Technical Reports Server (NTRS)

Krause, Linda Habash; Everding, Daniel; Bonner, Mathew; Swan, Brian

2012-01-01

We have developed a new collimated electron source called the Photoelectron Beam Generator (PEBG) for laboratory and spaceflight applications. This technology is needed to replace traditional cathodes because of serious fundamental weaknesses with the present state of the art. Filament cathodes suffer from numerous practical problems, even if expertly designed, including the dependence of electron emission on filament temperature, short lifetimes (approx 100 hours), and relatively high power (approx 10s of W). Other types of cathodes have solved some of these problems, but they are plagued with other difficult problems, such as the Spindt cathode's extreme sensitivity to molecular oxygen. None to date have been able to meet the demand of long lifetime, robust packaging, and precision energy and flux control. This new cathode design avoids many common pitfalls of traditional cathodes. Specifically, there are no fragile parts, no sensitivity to oxygen, no intrinsic emission dependencies on device temperature, and no vacuum requirements for protecting the source from contamination or damage. Recent advances in high-brightness Light Emitting Diodes (LEDs) have provided the key enabling technology for this new electron source. The LEDs are used to photoeject electrons off a target material of a low work-function, and these photoelectrons are subsequently focused into a laminar beam using electrostatic lenses. The PEBG works by illuminating a target material and steering photoelectrons into a laminar beam using electrostatic lenses

American College of Radiology-American Brachytherapy Society practice parameter for electronically generated low-energy radiation sources.

PubMed

Devlin, Phillip M; Gaspar, Laurie E; Buzurovic, Ivan; Demanes, D Jeffrey; Kasper, Michael E; Nag, Subir; Ouhib, Zoubir; Petit, Joshua H; Rosenthal, Seth A; Small, William; Wallner, Paul E; Hartford, Alan C

This collaborative practice parameter technical standard has been created between the American College of Radiology and American Brachytherapy Society to guide the usage of electronically generated low energy radiation sources (ELSs). It refers to the use of electronic X-ray sources with peak voltages up to 120 kVp to deliver therapeutic radiation therapy. The parameter provides a guideline for utilizing ELS, including patient selection and consent, treatment planning, and delivery processes. The parameter reviews the published clinical data with regard to ELS results in skin, breast, and other cancers. This technical standard recommends appropriate qualifications of the involved personnel. The parameter reviews the technical issues relating to equipment specifications as well as patient and personnel safety. Regarding suggestions for educational programs with regard to this parameter,it is suggested that the training level for clinicians be equivalent to that for other radiation therapies. It also suggests that ELS must be done using the same standards of quality and safety as those in place for other forms of radiation therapy. Copyright © 2017 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

Third user workshop on high-power lasers at the Linac Coherent Light Source

DOE PAGES

Bolme, Cynthia Anne; Glenzer, Sigfried; Fry, Alan

2016-03-24

On October 5–6, 2015, the third international user workshop focusing on high-power lasers at the Linac Coherent Light Source (LCLS) was held in Menlo Park, CA, USA [1 R. Falcone, S. Glenzer, and S. Hau-Riege, Synchrotron Radiation News 27(2), 56–58 (2014)., 2 P. Heimann and S. Glenzer, Synchrotron Radiation News 28(3), 54–56 (2015).]. Here, the workshop was co-organized by Los Alamos National Laboratory and SLAC National Accelerator Laboratory. More than 110 scientists attended from North America, Europe, and Asia to discuss high-energy-density (HED) science that is enabled by the unique combination of high-power lasers with the LCLS X-rays at themore » LCLS-Matter in Extreme Conditions (MEC) endstation.« less

21 CFR 179.21 - Sources of radiation used for inspection of food, for inspection of packaged food, and for...

Code of Federal Regulations, 2013 CFR

2013-04-01

... radiations at energy levels of not more than 2.2 million electron volts from one of the following isotopes... in food. (4) Machine sources producing X-radiation at energies no greater than 10 million electron...

21 CFR 179.21 - Sources of radiation used for inspection of food, for inspection of packaged food, and for...

Code of Federal Regulations, 2012 CFR

2012-04-01

... radiations at energy levels of not more than 2.2 million electron volts from one of the following isotopes... in food. (4) Machine sources producing X-radiation at energies no greater than 10 million electron...

21 CFR 179.21 - Sources of radiation used for inspection of food, for inspection of packaged food, and for...

Code of Federal Regulations, 2011 CFR

2011-04-01

... radiations at energy levels of not more than 2.2 million electron volts from one of the following isotopes... in food. (4) Machine sources producing X-radiation at energies no greater than 10 million electron...

Radiation noise of the bearing applied to the ceramic motorized spindle based on the sub-source decomposition method

NASA Astrophysics Data System (ADS)

Bai, X. T.; Wu, Y. H.; Zhang, K.; Chen, C. Z.; Yan, H. P.

2017-12-01

This paper mainly focuses on the calculation and analysis on the radiation noise of the angular contact ball bearing applied to the ceramic motorized spindle. The dynamic model containing the main working conditions and structural parameters is established based on dynamic theory of rolling bearing. The sub-source decomposition method is introduced in for the calculation of the radiation noise of the bearing, and a comparative experiment is adopted to check the precision of the method. Then the comparison between the contribution of different components is carried out in frequency domain based on the sub-source decomposition method. The spectrum of radiation noise of different components under various rotation speeds are used as the basis of assessing the contribution of different eigenfrequencies on the radiation noise of the components, and the proportion of friction noise and impact noise is evaluated as well. The results of the research provide the theoretical basis for the calculation of bearing noise, and offers reference to the impact of different components on the radiation noise of the bearing under different rotation speed.

HELIOS: A new open-source radiative transfer code

NASA Astrophysics Data System (ADS)

Malik, Matej; Grosheintz, Luc; Lukas Grimm, Simon; Mendonça, João; Kitzmann, Daniel; Heng, Kevin

2015-12-01

I present the new open-source code HELIOS, developed to accurately describe radiative transfer in a wide variety of irradiated atmospheres. We employ a one-dimensional multi-wavelength two-stream approach with scattering. Written in Cuda C++, HELIOS uses the GPU’s potential of massive parallelization and is able to compute the TP-profile of an atmosphere in radiative equilibrium and the subsequent emission spectrum in a few minutes on a single computer (for 60 layers and 1000 wavelength bins).The required molecular opacities are obtained with the recently published code HELIOS-K [1], which calculates the line shapes from an input line list and resamples the numerous line-by-line data into a manageable k-distribution format. Based on simple equilibrium chemistry theory [2] we combine the k-distribution functions of the molecules H2O, CO2, CO & CH4 to generate a k-table, which we then employ in HELIOS.I present our results of the following: (i) Various numerical tests, e.g. isothermal vs. non-isothermal treatment of layers. (ii) Comparison of iteratively determined TP-profiles with their analytical parametric prescriptions [3] and of the corresponding spectra. (iii) Benchmarks of TP-profiles & spectra for various elemental abundances. (iv) Benchmarks of averaged TP-profiles & spectra for the exoplanets GJ1214b, HD189733b & HD209458b. (v) Comparison with secondary eclipse data for HD189733b, XO-1b & Corot-2b.HELIOS is being developed, together with the dynamical core THOR and the chemistry solver VULCAN, in the group of Kevin Heng at the University of Bern as part of the Exoclimes Simulation Platform (ESP) [4], which is an open-source project aimed to provide community tools to model exoplanetary atmospheres.-----------------------------[1] Grimm & Heng 2015, ArXiv, 1503.03806[2] Heng, Lyons & Tsai, Arxiv, 1506.05501Heng & Lyons, ArXiv, 1507.01944[3] e.g. Heng, Mendonca & Lee, 2014, ApJS, 215, 4H[4] exoclime.net

Some neutron and gamma radiation characteristics of plutonium cermet fuel for isotopic power sources

NASA Technical Reports Server (NTRS)

Neff, R. A.; Anderson, M. E.; Campbell, A. R.; Haas, F. X.

1972-01-01

Gamma and neutron measurements on various types of plutonium sources are presented in order to show the effects of O-17, O-18 F-19, Pu-236, age of the fuel, and size of the source on the gamma and neutron spectra. Analysis of the radiation measurements shows that fluorine is the main contributor to the neutron yields from present plutonium-molybdenum cermet fuel, while both fluorine and Pu-236 daughters contribute significantly to the gamma ray intensities.

A new XUV optical end-station to characterize compact and flexible photonic devices using synchrotron radiation

NASA Astrophysics Data System (ADS)

Marcelli, A.; Mazuritskiy, M. I.; Dabagov, S. B.; Hampai, D.; Lerer, A. M.; Izotova, E. A.; D'Elia, A.; Turchini, S.; Zema, N.; Zuccaro, F.; de Simone, M.; Javad Rezvani, S.; Coreno, M.

2018-03-01

In this contribution we present the new experimental end-station to characterize XUV diffractive optics, such as Micro Channel Plates (MCPs) and other polycapillary optics, presently under commission at the Elettra synchrotron radiation laboratory (Trieste, Italy). To show the opportunities offered by these new optical devices for 3rd and 4th generation radiation sources, in this work we present also some patterns collected at different energies of the primary XUV radiation transmitted by MCP optical devices working in the normal incidence geometry.

[The opportunity to use combined stem cells transplantation for haemopoesis activation in the old and mature laboratory animals under the conditions of ionizing radiation].

PubMed

Grebnev, D U

2014-01-01

The objective of this work was to study the influence of combined transplantation of stem cells (multypotent mesenchimal stromal and hem poetic stem cells) on the haemopoesis of old and mature laboratory animals under the condition of ionizing radiation. The experiments were conducted on 48 white male mice with the body weight of 30 g, age of 3-4 months, and 48 male mice of 3 years of age and body mass of 50 g. The experiments for obtaining the MMSC and HSC cultures were conducted on 16 laboratory animals: female mice of 3-4 months of age and body mass of 30 g., 18 days gestation period. The control group was formed by the animals not under the ionizing radiation. The experimental group animals got the dose of 4 Gr. These animals also got MMSC and HSC mixture intravenously in the doses of 6 mln. c/kg. and 330 thousand cell/kg prospectively. The control group animals got the 0.9% NaCl - 0.2 ml. intravenously. The infusions were made 1 hour after radiation once. As the result of the experiment it was shown that under physiological conditions combined transplantation brings the erithropoesis activation, under the ionizing radiation conditions it brings the erythroid and granulocytopoesis activation. More over the combined MMSC and HSC transplantation gives cytoprotective action on the myeloid tissue due to decrease of cyto genically changed cells in the mature animals under the condition of ionizing radiation, but in the old animals this effect can be seen even under physiological condition. Conclusions: Combined transplantation of MMSC and GSC can be used in the mature and old laboratory animals under the conditions of ionising radiation for the haemopoesis activation.

L-shell spectroscopic diagnostics of radiation from krypton HED plasma sources.

PubMed

Petkov, E E; Safronova, A S; Kantsyrev, V L; Shlyaptseva, V V; Rawat, R S; Tan, K S; Beiersdorfer, P; Hell, N; Brown, G V

2016-11-01

X-ray spectroscopy is a useful tool for diagnosing plasma sources due to its non-invasive nature. One such source is the dense plasma focus (DPF). Recent interest has developed to demonstrate its potential application as a soft x-ray source. We present the first spectroscopic studies of krypton high energy density plasmas produced on a 3 kJ DPF device in Singapore. In order to diagnose spectral features, and to obtain a more comprehensive understanding of plasma parameters, a new non-local thermodynamic equilibrium L-shell kinetic model for krypton was developed. It has the capability of incorporating hot electrons, with different electron distribution functions, in order to examine the effects that they have on emission spectra. To further substantiate the validity of this model, it is also benchmarked with data gathered from experiments on the electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory, where data were collected using the high resolution EBIT calorimeter spectrometer.

L-shell spectroscopic diagnostics of radiation from krypton HED plasma sources

DOE PAGES

Petkov, E. E.; Safronova, A. S.; Kantsyrev, V. L.; ...

2016-08-09

We report that X-ray spectroscopy is a useful tool for diagnosing plasma sources due to its non-invasive nature. One such source is the dense plasma focus (DPF). Recent interest has developed to demonstrate its potential application as a soft x-ray source. We present the first spectroscopic studies of krypton high energy density plasmas produced on a 3 kJ DPF device in Singapore. In order to diagnose spectral features, and to obtain a more comprehensive understanding of plasma parameters, a new non-local thermodynamic equilibrium L-shell kinetic model for krypton was developed. It has the capability of incorporating hot electrons, with differentmore » electron distribution functions, in order to examine the effects that they have on emission spectra. Finally, to further substantiate the validity of this model, it is also benchmarked with data gathered from experiments on the electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory, where data were collected using the high resolution EBIT calorimeter spectrometer.« less

L-shell spectroscopic diagnostics of radiation from krypton HED plasma sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petkov, E. E., E-mail: emilp@unr.edu; Safronova, A. S.; Kantsyrev, V. L.

2016-11-15

X-ray spectroscopy is a useful tool for diagnosing plasma sources due to its non-invasive nature. One such source is the dense plasma focus (DPF). Recent interest has developed to demonstrate its potential application as a soft x-ray source. We present the first spectroscopic studies of krypton high energy density plasmas produced on a 3 kJ DPF device in Singapore. In order to diagnose spectral features, and to obtain a more comprehensive understanding of plasma parameters, a new non-local thermodynamic equilibrium L-shell kinetic model for krypton was developed. It has the capability of incorporating hot electrons, with different electron distribution functions,more » in order to examine the effects that they have on emission spectra. To further substantiate the validity of this model, it is also benchmarked with data gathered from experiments on the electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory, where data were collected using the high resolution EBIT calorimeter spectrometer.« less

Modeling Space Radiation with Radiomimetic Agent Bleomycin

NASA Technical Reports Server (NTRS)

Lu, Tao

2017-01-01

Space radiation consists of proton and helium from solar particle events (SPE) and high energy heavy ions from galactic cosmic ray (GCR). This mixture of radiation with particles at different energy levels has different effects on biological systems. Currently, majority studies of radiation effects on human were based on single-source radiation due to the limitation of available method to model effects of space radiation on living organisms. While NASA Space Radiation Laboratory is working on advanced switches to make it possible to have a mixed field radiation with particles of different energies, the radiation source will be limited. Development of an easily available experimental model for studying effects of mixed field radiation could greatly speed up our progress in our understanding the molecular mechanisms of damage and responses from exposure to space radiation, and facilitate the discovery of protection and countermeasures against space radiation, which is critical for the mission to Mars. Bleomycin, a radiomimetic agent, has been widely used to study radiation induced DNA damage and cellular responses. Previously, bleomycin was often compared to low low Linear Energy Transfer (LET) gamma radiation without defined characteristics. Our recent work demonstrated that bleomycin could induce complex clustered DNA damage in human fibroblasts that is similar to DNA damage induced by high LET radiation. These type of DNA damage is difficult to repair and can be visualized by gamma-H2Ax staining weeks after the initial insult. The survival ratio between early and late plating of human fibroblasts after bleomycin treatment is between low LET and high LET radiation. Our results suggest that bleomycin induces DNA damage and other cellular stresses resembling those resulted from mixed field radiation with both low and high LET particles. We hypothesize that bleomycin could be used to mimic space radiation in biological systems. Potential advantages and limitations of

Kinetic and radiation-hydrodynamic modeling of x-ray heating in laboratory photoionized plasmas

NASA Astrophysics Data System (ADS)

Mancini, Roberto

2017-06-01

In experiments performed at the Z facility of Sandia National Laboratories a cm-scale cell filled with neon gas was driven by the burst of broadband x-rays emitted at the collapse of a wire-array z-pinch turning the gas into a photoionized plasma. Transmission spectroscopy of a narrowband portion of the x-ray flux was used to diagnose the plasma. The data show a highly-ionized neon plasma with a rich line absorption spectrum that permits the extraction of the ionization distribution among Be-, Li-, He- and H-like ions. Analysis of the spectra produced atomic ground and low excited state areal densities in these ions, and from the ratio of first-excited to ground state populations in Li-like neon a temperature of 19±4eV was extracted to characterize the x-ray heating of the plasma. To interpret this observation, we have performed data-constrained view-factor calculations of the spectral distribution of the x-ray drive, self-consistent modeling of electron and atomic kinetics, and radiation-hydrodynamic simulations. For the conditions of the experiment, the electron distribution thermalizes quickly, has a negligible high-energy tail, and is very well approximated by a single Maxwellian distribution. Radiation-hydrodynamic simulations with either LTE or NLTE (i.e. non-equilibrium) atomic physics provide a more complete modeling of the experiment. We found that in order to compute electron temperatures consistent with observation inline non-equilibrium collisional-radiative neon atomic kinetics needs to be taken into account. We discuss the details of LTE and NLTE simulations, and the impact of atomic physics on the radiation heating and cooling rates that determine the plasma temperature. This work was sponsored in part by DOE Office of Science Grant DE-SC0014451, and the Z Facility Fundamental Science Program of SNL.

Sources of Ionizing Radiation in Interplanetary Space

NASA Image and Video Library

2013-05-30

This illustration depicts the two main types of radiation that NASA Radiation Assessment Detector RAD onboard Curiosity monitors, and how the magnetic field around Earth affects the radiation in space near Earth.

Solar cosmic rays as a specific source of radiation risk during piloted space flight.

PubMed

Petrov, V M

2004-01-01

Solar cosmic rays present one of several radiation sources that are unique to space flight. Under ground conditions the exposure to individuals has a controlled form and radiation risk occurs as stochastic radiobiological effects. Existence of solar cosmic rays in space leads to a stochastic mode of radiation environment as a result of which any radiobiological consequences of exposure to solar cosmic rays during the flight will be probabilistic values. In this case, the hazard of deterministic effects should also be expressed in radiation risk values. The main deterministic effect under space conditions is radiation sickness. The best dosimetric functional for its analysis is the blood forming organs dose equivalent but not an effective dose. In addition, the repair processes in red bone marrow affect strongly on the manifestation of this pathology and they must be taken into account for radiation risk assessment. A method for taking into account the mentioned above peculiarities for the solar cosmic rays radiation risk assessment during the interplanetary flights is given in the report. It is shown that radiation risk of deterministic effects defined, as the death probability caused by radiation sickness due to acute solar cosmic rays exposure, can be comparable to risk of stochastic effects. Its value decreases strongly because of the fractional mode of exposure during the orbital movement of the spacecraft. On the contrary, during the interplanetary flight, radiation risk of deterministic effects increases significantly because of the residual component of the blood forming organs dose from previous solar proton events. The noted quality of radiation responses must be taken into account for estimating radiation hazard in space. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Effect of Americium-241 Content on Plutonium Radiation Source Terms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rainisch, R.

1998-12-28

The management of excess plutonium by the US Department of Energy includes a number of storage and disposition alternatives. Savannah River Site (SRS) is supporting DOE with plutonium disposition efforts, including the immobilization of certain plutonium materials in a borosilicate glass matrix. Surplus plutonium inventories slated for vitrification include materials with elevated levels of Americium-241. The Am-241 content of plutonium materials generally reflects in-growth of the isotope due to decay of plutonium and is age-dependent. However, select plutonium inventories have Am-241 levels considerably above the age-based levels. Elevated levels of americium significantly impact radiation source terms of plutonium materials andmore » will make handling of the materials more difficult. Plutonium materials are normally handled in shielded glove boxes, and the work entails both extremity and whole body exposures. This paper reports results of an SRS analysis of plutonium materials source terms vs. the Americium-241 content of the materials. Data with respect to dependence and magnitude of source terms on/vs. Am-241 levels are presented and discussed. The investigation encompasses both vitrified and un-vitrified plutonium oxide (PuO2) batches.« less

Open-source Software for Demand Forecasting of Clinical Laboratory Test Volumes Using Time-series Analysis.

PubMed

Mohammed, Emad A; Naugler, Christopher

2017-01-01

Demand forecasting is the area of predictive analytics devoted to predicting future volumes of services or consumables. Fair understanding and estimation of how demand will vary facilitates the optimal utilization of resources. In a medical laboratory, accurate forecasting of future demand, that is, test volumes, can increase efficiency and facilitate long-term laboratory planning. Importantly, in an era of utilization management initiatives, accurately predicted volumes compared to the realized test volumes can form a precise way to evaluate utilization management initiatives. Laboratory test volumes are often highly amenable to forecasting by time-series models; however, the statistical software needed to do this is generally either expensive or highly technical. In this paper, we describe an open-source web-based software tool for time-series forecasting and explain how to use it as a demand forecasting tool in clinical laboratories to estimate test volumes. This tool has three different models, that is, Holt-Winters multiplicative, Holt-Winters additive, and simple linear regression. Moreover, these models are ranked and the best one is highlighted. This tool will allow anyone with historic test volume data to model future demand.

Open-source Software for Demand Forecasting of Clinical Laboratory Test Volumes Using Time-series Analysis

PubMed Central

Mohammed, Emad A.; Naugler, Christopher

2017-01-01

Background: Demand forecasting is the area of predictive analytics devoted to predicting future volumes of services or consumables. Fair understanding and estimation of how demand will vary facilitates the optimal utilization of resources. In a medical laboratory, accurate forecasting of future demand, that is, test volumes, can increase efficiency and facilitate long-term laboratory planning. Importantly, in an era of utilization management initiatives, accurately predicted volumes compared to the realized test volumes can form a precise way to evaluate utilization management initiatives. Laboratory test volumes are often highly amenable to forecasting by time-series models; however, the statistical software needed to do this is generally either expensive or highly technical. Method: In this paper, we describe an open-source web-based software tool for time-series forecasting and explain how to use it as a demand forecasting tool in clinical laboratories to estimate test volumes. Results: This tool has three different models, that is, Holt-Winters multiplicative, Holt-Winters additive, and simple linear regression. Moreover, these models are ranked and the best one is highlighted. Conclusion: This tool will allow anyone with historic test volume data to model future demand. PMID:28400996

WESF (173)Cs gamma ray sources

NASA Astrophysics Data System (ADS)

Kenna, B. T.

1984-10-01

The Waste Encapsulation and Storage Facility (WESP) at Hanford, Washington has been separating cesium from stored liquid defense waste since 1945. This is done to alleviate the heat generated by the decay of radioactive Cs137. The cesium is converted to CsCl, doubly encapsulated in 316l stainless steel, and placed in storage. The potential utility of these Cs137 capsules as gamma radiation sources was demonstrated. Registration of the capsule with the NRC as a sealed gamma source would facilitate the licensing of non-DOE irradiation facilities using this source. To grant this registration, the NRC requires characteristics of the capsule. It must also be demonstrated that the capsule will maintain its integrity under both normal circumstances and specified abnormal conditions. The required information is provided through collation of results of studies and tests done previously by other laboratories.

Overview of Atmospheric Ionizing Radiation (AIR)

NASA Technical Reports Server (NTRS)

Wilson, J. W.; Maiden, D. L.; Goldhagen, P.; Tai, H.; Shinn, J. L.

2003-01-01

The SuperSonic Transport (SST) development program within the US was based at the Langley Research Center as was the Apollo radiation testing facility (Space Radiation Effects Laboratory) with associated radiation research groups. It was natural for the issues of the SST to be first recognized by this unique combination of research programs. With a re-examination of the technologies for commercial supersonic flight and the possible development of a High Speed Civil Transport (HSCT), the remaining issues of the SST required resolution. It was the progress of SST radiation exposure research program founded by T. Foelsche at the Langley Research Center and the identified remaining issues after that project over twenty-five years ago which became the launch point of the current atmospheric ionizing radiation (AIR) research project. Added emphasis to the need for reassessment of atmospheric radiation resulted from the major lowering of the recommended occupational exposure limits, the inclusion of aircrew as radiation workers, and the recognition of civil aircrew as a major source of occupational exposures. Furthermore, the work of Ferenc Hajnal of the Environmental Measurements Laboratory brought greater focus to the uncertainties in the neutron flux at high altitudes. A re-examination of the issues involved was committed at the Langley Research Center and by the National Council on Radiation Protection (NCRP). As a result of the NCRP review, a new flight package was assembled and flown during solar minimum at which time the galactic cosmic radiation is at a maximum (June 1997). The present workshop is the initial analysis of the new data from that flight. The present paper is an overview of the status of knowledge of atmospheric ionizing radiations. We will re-examine the exposures of the world population and examine the context of aircrew exposures with implications for the results of the present research. A condensed version of this report was given at the 1998

SYNCHROTRON RADIATION, FREE ELECTRON LASER, APPLICATION OF NUCLEAR TECHNOLOGY, ETC.: Study on the characteristics of linac based THz light source

NASA Astrophysics Data System (ADS)

Zhu, Xiong-Wei; Wang, Shu-Hong; Chen, Sen-Yu

2009-10-01

There are many methods based on linac for THz radiation production. As one of the options for the Beijing Advanced Light, an ERL test facility is proposed for THz radiation. In this test facility, there are 4 kinds of methods to produce THz radiation: coherent synchrotron radiation (CSR), synchrotron radiation (SR), low gain FEL oscillator, and high gain SASE FEL. In this paper, we study the characteristics of the 4 kinds of THz light sources.

Radiation-associated lens changes in the cardiac catheterization laboratory: Results from the IC-CATARACT (CATaracts Attributed to RAdiation in the CaTh lab) study.

PubMed

Karatasakis, Aris; Brilakis, Harilaos S; Danek, Barbara A; Karacsonyi, Judit; Martinez-Parachini, Jose Roberto; Nguyen-Trong, Phuong-Khanh J; Alame, Aya J; Roesle, Michele K; Rangan, Bavana V; Rosenfield, Kenneth; Mehran, Roxana; Mahmud, Ehtisham; Chambers, Charles E; Banerjee, Subhash; Brilakis, Emmanouil S

2018-03-01

To examine the relationship between occupational exposure to ionizing radiation and the prevalence of lens changes in interventional cardiologists (ICs) and catheterization laboratory ("cath-lab") staff. Exposure to ionizing radiation is associated with the development of lens opacities. ICs and cath-lab staff can receive high doses of ionizing radiation without protection, and may thus be at risk for lens opacity formation. We conducted a cross-sectional study at an interventional cardiology conference. Study participants completed a questionnaire pertaining to occupational exposure to radiation and potential confounders for the development of cataracts, followed by slit-lamp examination and grading of lens findings. A total of 117 attendees participated in the study, including 99 (85%; 49 ± 11 years-old; 82% male) with occupational exposure to ionizing radiation and 18 (15%; 39 ± 12 years-old; 61% male) unexposed controls. The prevalence of overall cortical and posterior subcapsular lens changes (including subclinical findings) was higher in exposed participants compared with controls (47 vs. 17%, P = 0.015). Occupational exposure and age over 60 were independent predictors of lens changes (odds ratio [95% CI]: 6.07 [1.38-43.45] and 7.72 [1.60-43.34], respectively). The prevalence of frank opacities was low and similar between the two groups (14 vs. 6%, P = 0.461). Most lens findings consisted of subclinical changes in the periphery of the lens without impact on visual acuity. Compared with unexposed controls, ICs and cath-lab staff had a higher prevalence of lens changes that may be attributable to ionizing radiation exposure. While most of these changes were subclinical, they are important due to the potential to progress to clinical symptoms, highlighting the importance of minimizing staff radiation exposure. © 2017 Wiley Periodicals, Inc.

Effect of geometrical configuration of radioactive sources on radiation intensity in beta-voltaic nuclear battery system: A preliminary result

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basar, Khairul, E-mail: khbasar@fi.itb.ac.id; Riupassa, Robi D., E-mail: khbasar@fi.itb.ac.id; Bachtiar, Reza, E-mail: khbasar@fi.itb.ac.id

2014-01-01

It is known that one main problem in the application of beta-voltaic nuclear battery system is its low efficiency. The efficiency of the beta-voltaic nuclear battery system mainly depends on three aspects: source of radioactive radiation, interface between materials in the system and process of converting electron-hole pair to electric current in the semiconductor material. In this work, we show the effect of geometrical configuration of radioactive sources on radiation intensity of beta-voltaic nuclear battery system.

Black Carbon and Sulfate Aerosols in the Arctic: Long-term Trends, Radiative Impacts, and Source Attributions

NASA Astrophysics Data System (ADS)

Wang, H.; Zhang, R.; Yang, Y.; Smith, S.; Rasch, P. J.

2017-12-01

The Arctic has warmed dramatically in recent decades. As one of the important short-lived climate forcers, aerosols affect the Arctic radiative budget directly by interfering radiation and indirectly by modifying clouds. Light-absorbing particles (e.g., black carbon) in snow/ice can reduce the surface albedo. The direct radiative impact of aerosols on the Arctic climate can be either warming or cooling, depending on their composition and location, which can further alter the poleward heat transport. Anthropogenic emissions, especially, BC and SO2, have changed drastically in low/mid-latitude source regions in the past few decades. Arctic surface observations at some locations show that BC and sulfate aerosols had a decreasing trend in the recent decades. In order to understand the impact of long-term emission changes on aerosols and their radiative effects, we use the Community Earth System Model (CESM) equipped with an explicit BC and sulfur source-tagging technique to quantify the source-receptor relationships and decadal trends of Arctic sulfate and BC and to identify variations in their atmospheric transport pathways from lower latitudes. The simulation was conducted for 36 years (1979-2014) with prescribed sea surface temperatures and sea ice concentrations. To minimize potential biases in modeled large-scale circulations, wind fields in the simulation are nudged toward an atmospheric reanalysis dataset, while atmospheric constituents including water vapor, clouds, and aerosols are allowed to evolve according to the model physics. Both anthropogenic and open fire emissions came from the newly released CMIP6 datasets, which show strong regional trends in BC and SO2 emissions during the simulation time period. Results show that emissions from East Asia and South Asia together have the largest contributions to Arctic sulfate and BC concentrations in the upper troposphere, which have an increasing trend. The strong decrease in emissions from Europe, Russia and

The Exercise Physiology Laboratory--A Source of Health Promotion.

ERIC Educational Resources Information Center

Norris, William; Norred, Robert

1988-01-01

A visit to the Exercise Physiology Laboratory at the University of Tennessee is part of a physical education class required of all undergraduate students. The laboratory demonstration stimulates student interest and enrollment in physical education. Benefits to students, the laboratory, and the school are described. (MT)

Source Tracking of Nitrous Oxide using A Quantum Cascade Laser System in the Field and Laboratory Environments

EPA Science Inventory

Nitrous oxide is an important greenhouse gas and ozone depleting substance. Nitrification and denitrification are two major biological pathways that are responsible for soil emissions of N2O. However, source tracking of in-situ or laboratory N2O production is still challenging to...

Radiation Protection

NASA Astrophysics Data System (ADS)

Grupen, Claus

Radiation protection is a very important aspect for the application of particle detectors in many different fields, like high energy physics, medicine, materials science, oil and mineral exploration, and arts, to name a few. The knowledge of radiation units, the experience with shielding, and information on biological effects of radiation are vital for scientists handling radioactive sources or operating accelerators or X-ray equipment. This article describes the modern radiation units and their conversions to older units which are still in use in many countries. Typical radiation sources and detectors used in the field of radiation protection are presented. The legal regulations in nearly all countries follow closely the recommendations of the International Commission on Radiological Protection (ICRP). Tables and diagrams with relevant information on the handling of radiation sources provide useful data for the researcher working in this field.

Ultraviolet-B radiation enhancement in dielectric barrier discharge based xenon chloride exciplex source by air

NASA Astrophysics Data System (ADS)

Gulati, P.; Prakash, R.; Pal, U. N.; Kumar, M.; Vyas, V.

2014-07-01

A single barrier dielectric barrier discharge tube of quartz with multi-strip Titanium-Gold (Ti-Au) coatings have been developed and utilized for ultraviolet-B (UV-B) radiation production peaking at wavelength 308 nm. The observed radiation at this wavelength has been examined for the mixtures of the Xenon together with chlorine and air admixtures. The gas mixture composition, chlorine gas content, total gas pressure, and air pressure dependency of the UV intensity, has been analyzed. It is found that the larger concentration of Cl2 deteriorates the performance of the developed source and around 2% Cl2 in this source produced optimum results. Furthermore, an addition of air in the xenon and chlorine working gas environment leads to achieve same intensity of UV-B light but at lower working gas pressure where significant amount of gas is air.

Comparative Study of Two InGaAs-Based Reference Radiation Thermometers

NASA Astrophysics Data System (ADS)

Nasibov, H.; Diril, A.; Pehlivan, O.; Kalemci, M.

2017-07-01

More than one decade ago, an InGaAs detector-based transfer standard infrared radiation thermometer working in the temperature range from 150 {^{circ }}\\hbox {C} to 1100 {^{circ }}\\hbox {C} was built at TUBITAK UME in the scope of collaboration with IMGC (INRIM since 2006). During this timescale, the radiation thermometer was used for the dissemination of the radiation temperature scale below the silver fixed-point temperature. Recently, a new radiation thermometer with the same design but with different spectral responsivity was constructed and employed in the laboratory. In this work, we present the comparative study of these thermometers. Furthermore, the paper describes the measurement results of the thermometer's main characteristics such as the size-of-source effect, spectral responsivity, gain ratio, and linearity. Besides, both thermometers were calibrated at the freezing temperatures of indium, tin, zinc, aluminum, and copper reference fixed-point blackbodies. The main study is focused on the impact of the spectral responsivity of thermometers on the interpolation parameters of the Sakuma-Hattori equation. Furthermore, the calibration results and the uncertainty sources are discussed in this paper.

Advanced Small Animal Conformal Radiation Therapy Device.

PubMed

Sharma, Sunil; Narayanasamy, Ganesh; Przybyla, Beata; Webber, Jessica; Boerma, Marjan; Clarkson, Richard; Moros, Eduardo G; Corry, Peter M; Griffin, Robert J

2017-02-01

We have developed a small animal conformal radiation therapy device that provides a degree of geometrical/anatomical targeting comparable to what is achievable in a commercial animal irradiator. small animal conformal radiation therapy device is capable of producing precise and accurate conformal delivery of radiation to target as well as for imaging small animals. The small animal conformal radiation therapy device uses an X-ray tube, a robotic animal position system, and a digital imager. The system is in a steel enclosure with adequate lead shielding following National Council on Radiation Protection and Measurements 49 guidelines and verified with Geiger-Mueller survey meter. The X-ray source is calibrated following AAPM TG-61 specifications and mounted at 101.6 cm from the floor, which is a primary barrier. The X-ray tube is mounted on a custom-made "gantry" and has a special collimating assembly system that allows field size between 0.5 mm and 20 cm at isocenter. Three-dimensional imaging can be performed to aid target localization using the same X-ray source at custom settings and an in-house reconstruction software. The small animal conformal radiation therapy device thus provides an excellent integrated system to promote translational research in radiation oncology in an academic laboratory. The purpose of this article is to review shielding and dosimetric measurement and highlight a few successful studies that have been performed to date with our system. In addition, an example of new data from an in vivo rat model of breast cancer is presented in which spatially fractionated radiation alone and in combination with thermal ablation was applied and the therapeutic benefit examined.

Phase contrast tomography of the mouse cochlea at microfocus x-ray sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bartels, Matthias; Krenkel, Martin; Hernandez, Victor H.

2013-08-19

We present phase contrast x-ray tomography of functional soft tissue within the bony cochlear capsule of mice, carried out at laboratory microfocus sources with well-matched source, detector, geometry, and reconstruction algorithms at spatial resolutions down to 2 μm. Contrast, data quality and resolution enable the visualization of thin membranes and nerve fibers as well as automated segmentation of surrounding bone. By complementing synchrotron radiation imaging techniques, a broad range of biomedical applications becomes possible as demonstrated for optogenetic cochlear implant research.

A radiation quality correction factor k for well-type ionization chambers for the measurement of the reference air kerma rate of (60)Co HDR brachytherapy sources.

PubMed

Schüller, Andreas; Meier, Markus; Selbach, Hans-Joachim; Ankerhold, Ulrike

2015-07-01

The aim of this study was to investigate whether a chamber-type-specific radiation quality correction factor kQ can be determined in order to measure the reference air kerma rate of (60)Co high-dose-rate (HDR) brachytherapy sources with acceptable uncertainty by means of a well-type ionization chamber calibrated for (192)Ir HDR sources. The calibration coefficients of 35 well-type ionization chambers of two different chamber types for radiation fields of (60)Co and (192)Ir HDR brachytherapy sources were determined experimentally. A radiation quality correction factor kQ was determined as the ratio of the calibration coefficients for (60)Co and (192)Ir. The dependence on chamber-to-chamber variations, source-to-source variations, and source strength was investigated. For the PTW Tx33004 (Nucletron source dosimetry system (SDS)) well-type chamber, the type-specific radiation quality correction factor kQ is 1.19. Note that this value is valid for chambers with the serial number, SN ≥ 315 (Nucletron SDS SN ≥ 548) onward only. For the Standard Imaging HDR 1000 Plus well-type chambers, the type-specific correction factor kQ is 1.05. Both kQ values are independent of the source strengths in the complete clinically relevant range. The relative expanded uncertainty (k = 2) of kQ is UkQ = 2.1% for both chamber types. The calibration coefficient of a well-type chamber for radiation fields of (60)Co HDR brachytherapy sources can be calculated from a given calibration coefficient for (192)Ir radiation by using a chamber-type-specific radiation quality correction factor kQ. However, the uncertainty of a (60)Co calibration coefficient calculated via kQ is at least twice as large as that for a direct calibration with a (60)Co source.

Nonlinear radiative heat flux and heat source/sink on entropy generation minimization rate

NASA Astrophysics Data System (ADS)

Hayat, T.; Khan, M. Waleed Ahmed; Khan, M. Ijaz; Alsaedi, A.

2018-06-01

Entropy generation minimization in nonlinear radiative mixed convective flow towards a variable thicked surface is addressed. Entropy generation for momentum and temperature is carried out. The source for this flow analysis is stretching velocity of sheet. Transformations are used to reduce system of partial differential equations into ordinary ones. Total entropy generation rate is determined. Series solutions for the zeroth and mth order deformation systems are computed. Domain of convergence for obtained solutions is identified. Velocity, temperature and concentration fields are plotted and interpreted. Entropy equation is studied through nonlinear mixed convection and radiative heat flux. Velocity and temperature gradients are discussed through graphs. Meaningful results are concluded in the final remarks.

NATIONAL- AND STATE-LEVEL EMISSIONS ESTIMATES OF RADIATIVELY IMPORTANT TRACE GASES (RITGS) FROM ANTHROPOGENIC SOURCES

EPA Science Inventory

The report documents the development of national- and state- level emissions estimates of radiatively important trace gases (RlTGs). Emissions estimates are presented for the principal anthropogenic sources of carbon dioxide (CO2), methane (CH4), chlorofluorocarbons (CFCs), and o...

Radiation Protection

MedlinePlus

... Offices Regional Offices Labs and Research Centers Radiation Protection Contact Us Share Dose Calculator Use the Radiation ... the Office of Air and Radiation (OAR) Radiation Protection Radiation Sources and Doses Calculate Your Radiation Dose ...

LUNAR RECEIVING LABORATORY (LRL) - CLARK, ROBERT, DR. - JSC

NASA Image and Video Library

1973-11-05

S73-36161 (November 1973) --- In the Radiation Counting Laboratory sixty feet underground at JSC, Dr. Robert S. Clark prepares to load pieces of iridium foil -- sandwiched between plastic sheets -- into the laboratory's radiation detector. The iridium foil strips were worn by the crew of the second Skylab flight in personal radiation dosimeters throughout their 59 1/2 days in space. Inside the radiation detector assembly surrounded by 28 tons of lead shielding, the sample will be tested to determine the total neutron dose to which the astronauts were exposed during their long stay aboard the space station. Photo credit: NASA

Microbeam radiation therapy

NASA Astrophysics Data System (ADS)

Laissue, Jean A.; Lyubimova, Nadia; Wagner, Hans-Peter; Archer, David W.; Slatkin, Daniel N.; Di Michiel, Marco; Nemoz, Christian; Renier, Michel; Brauer, Elke; Spanne, Per O.; Gebbers, Jan-Olef; Dixon, Keith; Blattmann, Hans

1999-10-01

The central nervous system of vertebrates, even when immature, displays extraordinary resistance to damage by microscopically narrow, multiple, parallel, planar beams of x rays. Imminently lethal gliosarcomas in the brains of mature rats can be inhibited and ablated by such microbeams with little or no harm to mature brain tissues and neurological function. Potentially palliative, conventional wide-beam radiotherapy of malignant brain tumors in human infants under three years of age is so fraught with the danger of disrupting the functional maturation of immature brain tissues around the targeted tumor that it is implemented infrequently. Other kinds of therapy for such tumors are often inadequate. We suggest that microbeam radiation therapy (MRT) might help to alleviate the situation. Wiggler-generated synchrotron x-rays were first used for experimental microplanar beam (microbeam) radiation therapy (MRT) at Brookhaven National Laboratory's National Synchrotron Light Source in the early 1990s. We now describe the progress achieved in MRT research to date using immature and adult rats irradiated at the European Synchrotron Radiation Facility in Grenoble, France, and investigated thereafter at the Institute of Pathology of the University of Bern.

[How do hospital clinical laboratories and laboratory testing companies cooperate and build reciprocal relations?].

PubMed

Kawano, Seiji

2014-12-01

As the 2nd Joint Symposium of the Japanese Society of Laboratory Medicine and the Japanese Association of Laboratory Pathologists, the symposium on clinical test out-sourcing and branch laboratories was held at the 60th General Meeting of the Japanese Society of Laboratory Medicine on November 2nd, 2013 in Kobe. For the symposium, we conducted a questionnaire survey on the usage of clinical test out-sourcing and the introduction of branch laboratories to clinical laboratories of Japanese university hospitals, both private and public, between July 25th and August 20th, 2013. Seventy-two hospitals responded to the questionnaire survey, consisting of 41 public medical school hospitals and 31 private ones. According to the survey, the selection of each clinical test for out-sourcing was mainly determined by the capacities of hospital clinical laboratories and their equipment, as well as the profitability of each test. The main concerns of clinical laboratory members of university hospitals involved the continuity of measurement principles, traceability, and standardization of reference values for each test. They strongly requested the interchangeability and computerization of test data between laboratory testing companies. A branch laboratory was introduced to six hospitals, all of which were private medical college hospitals, out of 72 university hospitals, and eight of the other hospitals were open to its introduction. The merits and demerits of introducing a branch laboratory were also discussed. (Review).

Directional radiation detectors

DOEpatents

Dowell, Jonathan L.

2017-09-12

Directional radiation detectors and systems, methods, and computer-readable media for using directional radiation detectors to locate a radiation source are provided herein. A directional radiation detector includes a radiation sensor. A radiation attenuator partially surrounds the radiation sensor and defines an aperture through which incident radiation is received by the radiation sensor. The aperture is positioned such that when incident radiation is received directly through the aperture and by the radiation sensor, a source of the incident radiation is located within a solid angle defined by the aperture. The radiation sensor senses at least one of alpha particles, beta particles, gamma particles, or neutrons.

GCR Simulator Development Status at the NASA Space Radiation Laboratory

NASA Technical Reports Server (NTRS)

Slaba, T. C.; Norbury, J. W.; Blattnig, S. R.

2015-01-01

There are large uncertainties connected to the biological response for exposure to galactic cosmic rays (GCR) on long duration deep space missions. In order to reduce the uncertainties and gain understanding about the basic mechanisms through which space radiation initiates cancer and other endpoints, radiobiology experiments are performed with mono-energetic ions beams. Some of the accelerator facilities supporting such experiments have matured to a point where simulating the broad range of particles and energies characteristic of the GCR environment in a single experiment is feasible from a technology, usage, and cost perspective. In this work, several aspects of simulating the GCR environment at the NASA Space Radiation Laboratory (NSRL) are discussed. First, comparisons are made between direct simulation of the external, free space GCR field, and simulation of the induced tissue field behind shielding. It is found that upper energy constraints at NSRL limit the ability to simulate the external, free space field directly (i.e. shielding placed in the beam line in front of a biological target and exposed to a free space spectrum). Second, a reference environment for the GCR simulator and suitable for deep space missions is identified and described in terms of fluence and integrated dosimetric quantities. Analysis results are given to justify the use of a single reference field over a range of shielding conditions and solar activities. Third, an approach for simulating the reference field at NSRL is presented. The approach directly considers the hydrogen and helium energy spectra, and the heavier ions are collectively represented by considering the linear energy transfer (LET) spectrum. While many more aspects of the experimental setup need to be considered before final implementation of the GCR simulator, this preliminary study provides useful information that should aid the final design. Possible drawbacks of the proposed methodology are discussed and weighed

Guided Radiation Beams in Free Electron Lasers.

DTIC Science & Technology

1988-05-19

the electron beam in an FEL that the radiation beam will remain guided. 0 20 II. Refractive Index Associated with FELs In our model, the vector ...eIAw/ymOc(exp(ikwz) + c.c.) ex/2 , is the wiggle velocity, y is the Lorentz factor, Aw is the vector potential amplitude of the planar wiggler...Balboa Avenue Palo Alto, CA 94303 San Diego, CA 92123 38 Dr. S. Krinsky Nat. Synchrotron Light Source Dr. Michael Lavan Brookhaven National Laboratory U.S

Stereo x-ray photogrammetry applied for prevention of sigmoid-colon damage caused by radiation from intrauterine sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuipers, T.

1982-06-01

Radiation therapy of cervix carcinoma is applied in this Institute by means of modified Stockholm method in combination with external beam irradiation. In 1968, parametrial portals were replaced by large planeparallel opposed fields extending cranially to LIII/LIV with central shielding in order to avoid overdosage in the area of intracavitary treatment. This resulted in a marked increased incidence of serere sigmoid-colon radiation lesions from 0.25% to 4%; predominantly in Stage I and II patients. Therefore two measures have been introduced: beginning in 1972 measures were taken to prevent the cranial displacement of the uterus during intracavitary treatment in order tomore » avoid shortening the distance between the radioactive sources and the sigmoid-colon; from 1973 stereo X ray photogrammetry (SRM) was applied for dose determinations at points of the sigmoid-colon, which were seen to be located close to the applicator. When SRM data indicated that a high dose at the sigmoid-colon might occur, treatment modifications enabled prevention of radiation damage. Change of position of the applicator was the first to be considered. In the last seven years no surgical intervention had to be performed because of a sigmoid-colon lesion resulting from an unexpected high radiation dose delivered by intrauterine sources. The local recurrence rate was not increased following treatment modifications for prevention of sigmoid-colon radiation damage.« less

Ultraviolet-B radiation enhancement in dielectric barrier discharge based xenon chloride exciplex source by air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gulati, P., E-mail: pgulati1512@gmail.com; Department of Physics, Banasthali University, P.O. Banasthali Vidyapith, Rajasthan 304022; Prakash, R.

2014-07-07

A single barrier dielectric barrier discharge tube of quartz with multi-strip Titanium-Gold (Ti-Au) coatings have been developed and utilized for ultraviolet-B (UV-B) radiation production peaking at wavelength 308 nm. The observed radiation at this wavelength has been examined for the mixtures of the Xenon together with chlorine and air admixtures. The gas mixture composition, chlorine gas content, total gas pressure, and air pressure dependency of the UV intensity, has been analyzed. It is found that the larger concentration of Cl{sub 2} deteriorates the performance of the developed source and around 2% Cl{sub 2} in this source produced optimum results. Furthermore, anmore » addition of air in the xenon and chlorine working gas environment leads to achieve same intensity of UV-B light but at lower working gas pressure where significant amount of gas is air.« less

Illumination system having a plurality of movable sources

DOEpatents

Sweatt, William C.; Kubiak, Glenn D.

2002-01-01

An illumination system includes several discharge sources that are multiplexed together to reduce the amount of debris generated. The system includes: (a) a first electromagnetic radiation source array that includes a plurality of first activatable radiation source elements that are positioned on a first movable carriage; (b) a second electromagnetic radiation source array that includes a plurality of second activatable radiation source elements that are positioned on a second movable carriage; (c) means for directing electromagnetic radiation from the first electromagnetic radiation source array and electromagnetic radiation from the second electromagnetic radiation source array toward a common optical path; (d) means for synchronizing (i) the movements of the first movable carriage and of the second movable carriage and (ii) the activation of the first electromagnetic radiation source array and of the second electromagnetic radiation source array to provide an essentially continuous illumination of electromagnetic radiation along the common optical path.

Intermittent Astrophysical Radiation Sources and Terrestrial Life

NASA Astrophysics Data System (ADS)

Melott, Adrian

2013-04-01

Terrestrial life is exposed to a variety of radiation sources. Astrophysical observations suggest that strong excursions in cosmic ray flux and spectral hardness are expected. Gamma-ray bursts and supernovae are expected to irradiate the atmosphere with keV to GeV photons at irregular intervals. Supernovae will produce large cosmic ray excursions, with time development varying with distance from the event. Large fluxes of keV to MeV protons from the Sun pose a strong threat to electromagnetic technology. The terrestrial record shows cosmogenic isotope excursions which are consistent with major solar proton events, and there are observations of G-stars suggesting that the rate of such events may be much higher than previously assumed. In addition there are unknown and unexplained astronomical transients which may indicate new classes of events. The Sun, supernovae, and gamma-ray bursts are all capable of producing lethal fluences, and some are expected on intervals of 10^8 years or so. The history of life on Earth is filled with mass extinctions at a variety of levels of intensity. Most are not understood. Astrophysical radiation may play a role, particularly from large increases in muon irradiation on the ground, and changes in atmospheric chemistry which deplete ozone, admitting increased solar UVB. UVB is strongly absorbed by DNA and proteins, and breaks the chemical bonds---it is a known carcinogen. High muon fluxes will also be damaging to such molecules, but experiments are needed to pin down the rate. Solar proton events which are not directly dangerous for the biota may nevertheless pose a major threat to modern electromagnetic technology through direct impact on satellites and magnetic induction of large currents in power grids, disabling transformers. We will look at the kind of events that are expected on timescales from human to geological, and their likely consequences.

Shielding calculations for the National Synchrotron Light Source-II experimental beamlines

NASA Astrophysics Data System (ADS)

Job, Panakkal K.; Casey, William R.

2013-01-01

Brookhaven National Laboratory is in the process of building a new Electron storage ring for scientific research using synchrotron radiation. This facility, called the "National Synchrotron Light Source II" (NSLS-II), will provide x-ray radiation of ultra-high brightness and exceptional spatial and energy resolution. It will also provide advanced insertion devices, optics, detectors, and robotics, designed to maximize the scientific output of the facility. The project scope includes the design of an electron storage ring and the experimental beamlines, which stores a maximum of 500 mA electron beam current at an energy of 3.0 GeV. When fully built there will be at least 58 beamlines using synchrotron radiation for experimental programs. It is planned to operate the facility primarily in a top-off mode, thereby maintaining the maximum variation in the synchrotron radiation flux to <1%. Because of the very demanding requirements for synchrotron radiation brilliance for the experiments, each of the 58 beamlines will be unique in terms of the source properties and experimental configuration. This makes the shielding configuration of each of the beamlines unique. The shielding calculation methodology and the results for five representative beamlines of NSLS-II, have been presented in this paper.

Radiation damage in a micron-sized protein crystal studied via reciprocal space mapping and Bragg coherent diffractive imaging.

PubMed

Coughlan, H D; Darmanin, C; Phillips, N W; Hofmann, F; Clark, J N; Harder, R J; Vine, D J; Abbey, B

2015-07-01

For laboratory and synchrotron based X-ray sources, radiation damage has posed a significant barrier to obtaining high-resolution structural data from biological macromolecules. The problem is particularly acute for micron-sized crystals where the weaker signal often necessitates the use of higher intensity beams to obtain the relevant data. Here, we employ a combination of techniques, including Bragg coherent diffractive imaging to characterise the radiation induced damage in a micron-sized protein crystal over time. The approach we adopt here could help screen for potential protein crystal candidates for measurement at X-ray free election laser sources.

Radiation damage in a micron-sized protein crystal studied via reciprocal space mapping and Bragg coherent diffractive imaging

PubMed Central

Coughlan, H. D.; Darmanin, C.; Phillips, N. W.; Hofmann, F.; Clark, J. N.; Harder, R. J.; Vine, D. J.; Abbey, B.

2015-01-01

For laboratory and synchrotron based X-ray sources, radiation damage has posed a significant barrier to obtaining high-resolution structural data from biological macromolecules. The problem is particularly acute for micron-sized crystals where the weaker signal often necessitates the use of higher intensity beams to obtain the relevant data. Here, we employ a combination of techniques, including Bragg coherent diffractive imaging to characterise the radiation induced damage in a micron-sized protein crystal over time. The approach we adopt here could help screen for potential protein crystal candidates for measurement at X-ray free election laser sources. PMID:26798804

Radiation damage in a micron-sized protein crystal studied via reciprocal space mapping and Bragg coherent diffractive imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coughlan, H. D.; Darmanin, C.; Phillips, N. W.

For laboratory and synchrotron based X-ray sources, radiation damage has posed a significant barrier to obtaining high-resolution structural data from biological macromolecules. The problem is particularly acute for micron-sized crystals where the weaker signal often necessitates the use of higher intensity beams to obtain the relevant data. Here, we employ a combination of techniques, including Bragg coherent diffractive imaging to characterise the radiation induced damage in a micron-sized protein crystal over time. The approach we adopt here could help screen for potential protein crystal candidates for measurement at X-ray free election laser sources.

Radiation damage in a micron-sized protein crystal studied via reciprocal space mapping and Bragg coherent diffractive imaging

DOE PAGES

Coughlan, H. D.; Darmanin, C.; Phillips, N. W.; ...

2015-04-29

For laboratory and synchrotron based X-ray sources, radiation damage has posed a significant barrier to obtaining high-resolution structural data from biological macromolecules. The problem is particularly acute for micron-sized crystals where the weaker signal often necessitates the use of higher intensity beams to obtain the relevant data. Here, we employ a combination of techniques, including Bragg coherent diffractive imaging to characterise the radiation induced damage in a micron-sized protein crystal over time. The approach we adopt here could help screen for potential protein crystal candidates for measurement at X-ray free election laser sources.

Laser-plasma extreme ultraviolet and soft X-ray sources based on a double stream gas puff target: interaction of the radiation pulses with matter

NASA Astrophysics Data System (ADS)

Bartnik, A.

2015-06-01

In this work a review of investigations concerning interaction of intense extreme ultraviolet (EUV) and soft X-ray (SXR) pulses with matter is presented. The investigations were performed using laser-produced plasma (LPP) EUV/SXR sources based on a double stream gas puff target. The sources are equipped with dedicated collectors allowing for efficient focusing of the EUV/SXR radiation pulses. Intense radiation in a wide spectral range, as well as a quasi-monochromatic radiation can be produced. In the paper different kinds of LPP EUV/SXR sources developed in the Institute of Optoelectronics, Military University of Technology are described. Radiation intensities delivered by the sources are sufficient for different kinds of interaction experiments including EUV/SXR induced ablation, surface treatment, EUV fluorescence or photoionized plasma creation. A brief review of the main results concerning this kind of experiments performed by author of the paper are presented. However, since the LPP sources cannot compete with large scale X-ray sources like synchrotrons, free electron lasers or high energy density plasma sources, it was indicated that some investigations not requiring extreme irradiation parameters can be performed using the small scale installations. Some results, especially concerning low temperature photoionized plasmas are very unique and could be hardly obtained using the large facilities.

Plutonium radiation surrogate

DOEpatents

Frank, Michael I [Dublin, CA

2010-02-02

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.

Radiation Hazard Detector

NASA Technical Reports Server (NTRS)

1978-01-01

NASA technology has made commercially available a new, inexpensive, conveniently-carried device for protection, of people exposed to potentially dangerous levels of microwave radiation. Microwaves are radio emissions of extremely high frequency. They can be hazardous but the degree of hazard is not yet well understood. Generally, it is believed that low intensity radiation of short duration is not harmful but that exposure to high levels can induce deep internal burns, affecting the circulatory and nervous systems, and particularly the eyes. The Department of Labor's Occupational Safety and Health Administration (OSHA) has established an allowable safe threshold of exposure. However, people working near high intensity sources of microwave energy-for example, radar antennas and television transmitters-may be unknowingly exposed to radiation levels beyond the safe limit. This poses not only a personal safety problem but also a problem for employers in terms of productivity loss, workman's compensation claims and possible liability litigation. Earlier-developed monitoring devices which warn personnel of dangerous radiation levels have their shortcomings. They can be cumbersome and awkward to use while working. They also require continual visual monitoring to determine if a person is in a dangerous area of radiation, and they are relatively expensive, another deterrent to their widespread adoption. In response to the need for a cheaper and more effective warning system, Jet Propulsion Laboratory developed, under NASA auspices, a new, battery-powered Microwave Radiation Hazard Detector. To bring the product to the commercial market, California Institute Research Foundation, the patent holder, granted an exclusive license to Cicoil Corporation, Chatsworth, California, an electronic components manufacturer.

An open-source, extensible system for laboratory timing and control

NASA Astrophysics Data System (ADS)

Gaskell, Peter E.; Thorn, Jeremy J.; Alba, Sequoia; Steck, Daniel A.

2009-11-01

We describe a simple system for timing and control, which provides control of analog, digital, and radio-frequency signals. Our system differs from most common laboratory setups in that it is open source, built from off-the-shelf components, synchronized to a common and accurate clock, and connected over an Ethernet network. A simple bus architecture facilitates creating new and specialized devices with only moderate experience in circuit design. Each device operates independently, requiring only an Ethernet network connection to the controlling computer, a clock signal, and a trigger signal. This makes the system highly robust and scalable. The devices can all be connected to a single external clock, allowing synchronous operation of a large number of devices for situations requiring precise timing of many parallel control and acquisition channels. Provided an accurate enough clock, these devices are capable of triggering events separated by one day with near-microsecond precision. We have achieved precisions of ˜0.1 ppb (parts per 109) over 16 s.

Design and verification of the shielding around the new Neutron Standards Laboratory (LPN) at CIEMAT.

PubMed

Méndez-Villafañe, R; Guerrero, J E; Embid, M; Fernández, R; Grandio, R; Pérez-Cejuela, P; Márquez, J L; Alvarez, F; Ortego, P

2014-10-01

The construction of the new Neutron Standards Laboratory at CIEMAT (Laboratorio de Patrones Neutrónicos) has been finalised and is ready to provide service. The facility is an ∼8 m×8 m×8 m irradiation vault, following the International Organization for Standardization 8529 recommendations. It relies on several neutron sources: a 5-GBq (5.8× 10(8) s(-1)) (252)Cf source and two (241)Am-Be neutron sources (185 and 11.1 GBq). The irradiation point is located 4 m over the ground level and in the geometrical centre of the room. Each neutron source can be moved remotely from its storage position inside a water pool to the irradiation point. Prior to this, an important task to design the neutron shielding and to choose the most appropriate materials has been developed by the Radiological Security Unit and the Ionizing Radiations Metrology Laboratory. MCNPX was chosen to simulate the irradiation facility. With this information the walls were built with a thickness of 125 cm. Special attention was put on the weak points (main door, air conditioning system, etc.) so that the ambient dose outside the facility was below the regulatory limits. Finally, the Radiation Protection Unit carried out a set of measurements in specific points around the installation with an LB6411 neutron monitor and a Reuter-Stokes high-pressure ion chamber to verify experimentally the results of the simulation. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Laboratory Investigation of Astrophysical Collimated Jets with Intense Lasers

NASA Astrophysics Data System (ADS)

Yuan, Dawei; Li, Yutong; Tao, Tao; Wei, Huigang; Zhong, Jiayong; Zhu, Baojun; Li, Yanfei; Zhao, Jiarui; Li, Fang; Han, Bo; Zhang, Zhe; Liang, Guiyun; Wang, Feilu; Hu, Guangyue; Zheng, Jian; Jiang, Shaoen; Du, Kai; Ding, Yongkun; Zhou, Shenlei; Zhu, Baoqiang; Zhu, Jianqiang; Zhao, Gang; Zhang, Jie

2018-06-01

One of the remarkable dynamic features of the Herbig–Haro (HH) object is its highly collimated propagation far away from the accretion disk. Different factors are proposed to give us a clearly physical explanation behind these fascinating phenomena, including magnetic field, radiation cooling, surrounding medium, and so on. Laboratory astrophysics, as a new complementary method of studying astrophysical issues, can provide an insight into these behaviors in a similar and controllable laboratory environment. Here we report the scaled laboratory experiments that a well-collimated radiative jet with high Mach number is successfully created to mimic the evolution of HH objects. According to our results, we find that the radiation cooling effect within the jet and the outer rare surrounding plasmas from the X-ray (>keV) photoionized target contribute to the jet collimation. The local nonuniform density structures along the collimated radiative jet axis are caused by the pressure competition between the inner jet and the outer plasmas. The corresponding simulations performed with radiation-hydrodynamic codes FLASH reveal how the radiative jet evolves.

Laboratory Investigations of the Complex Refractory Organic Material Produced from Irradiation of Pluto Ice Analogs

NASA Technical Reports Server (NTRS)

Materese, Christopher K.; Cruikshank, Dale P.; Sanford, Scott A.; Imanaka, Hiroshi

2014-01-01

Much of Pluto's surface consists of N2 ice with smaller amounts of CH4 and CO ices. Despite the low temperature (approximately 45K), chemistry can be driven in the surface ices by radiation processing such as cosmic ray bombardment. When cosmic rays strike the surface, much of their energy is dispersed in the form of secondary electrons, which in turn drive much of the resulting chemical reactions. Laboratory experiments designed to simulate the conditions on these icy bodies may provide insight into this chemistry. Significant progress has been made in the laboratory toward understanding the smaller, simple compounds produced in the solid phase by radiation processing of (N2, CH4, CO) ices (Bohn et al. 1994; Moore & Hudson 2003; Hodyss et al. 2011; Kim and Kaiser 2012). Recently Materese et al. (2014) used a variety of techniques to better characterize the refractory materials produced from the UV photo-irradiation of N2:CH4:CO ices. However, because Pluto's atmosphere is optically thick to Lyman-alpha UV radiation it is important to re-examine the results using an alternate radiation source. Our latest work has consisted of the analysis of refractory materials produced from the electron bombardment of low temperature N2(-), CH4(-), and CO(-)containing ices (100:1:1). The ice mixture was chosen to be analogous to the known surface ices on Pluto and the radiation source was chosen to mimic the secondary electrons produced by cosmic rays bombardment. The residues were studied using multiple chemical techniques including, infrared (IR) spectroscopy, X-ray absorption near-edge structure (XANES) spectroscopy, and gas chromatography coupled with mass spectrometry (GC-MS). The organic residues produced in these experiments can be seen as an analog for the refractory component of the surface of Pluto, and are compared with the residues previously obtained from UV photo-irradiation. UV and near- IR spectroscopy of the surfaces of Pluto and Charon during the encounter with

AN ESTIMATION OF THE EXPOSURE OF THE POPULATION OF ISRAEL TO NATURAL SOURCES OF IONIZING RADIATION.

PubMed

Epstein, L; Koch, J; Riemer, T; Haquin, G; Orion, I

2017-11-01

The radiation dose to the population of Israel due to exposure to natural sources of ionizing radiation was assessed. The main contributor to the dose is radon that accounts for 60% of the exposure to natural sources. The dose due to radon inhalation was assessed by combining the results of a radon survey in single-family houses with the results of a survey in apartments in multi-storey buildings. The average annual dose due to radon inhalation was found to be 1.2 mSv. The dose rate due to exposure to cosmic radiation was assessed using a code that calculates the dose rate at different heights above sea level, taking into account the solar cycle. The annual dose was calculated based on the fraction of time spent indoors and the attenuation provided by buildings and was found to be 0.2 mSv. The annual dose due to external exposure to the terrestrial radionuclides was similarly assessed. The indoor dose rate was calculated using a model that takes into account the concentrations of the natural radionuclides in building materials, the density and the thickness of the walls. The dose rate outdoors was calculated based on the concentrations of the natural radionuclides in different geological units in Israel as measured in an aerial survey and measurements above ground. The annual dose was found to be 0.2 mSv. Doses due to internal exposure other than exposure to radon were also calculated and were found to be 0.4 mSv. The overall annual exposure of the population of Israel to natural sources of ionizing radiation is therefore 2 mSv and ranges between 1.7 and 2.7 mSv. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Monte Carlo study of a 60Co calibration field of the Dosimetry Laboratory Seibersdorf.

PubMed

Hranitzky, C; Stadtmann, H

2007-01-01

The gamma radiation fields of the reference irradiation facility of the Dosimetry Laboratory Seibersdorf with collimated beam geometry are used for calibrating radiation protection dosemeters. A close-to-reality simulation model of the facility including the complex geometry of a 60Co source was set up using the Monte Carlo code MCNP. The goal of this study is to characterise the radionuclide gamma calibration field and resulting air-kerma distributions inside the measurement hall with a total of 20 m in length. For the whole range of source-detector-distances (SDD) along the central beam axis, simulated and measured relative air-kerma values are within +/-0.6%. Influences on the accuracy of the simulation results are investigated, including e.g., source mass density effects or detector volume dependencies. A constant scatter contribution from the lead ring-collimator of approximately 1% and an increasing scatter contribution from the concrete floor for distances above 7 m are identified, resulting in a total air-kerma scatter contribution below 5%, which is in accordance to the ISO 4037-1 recommendations.

Laboratory modeling of multiple zonal jets on the polar beta-plane

NASA Astrophysics Data System (ADS)

Afanasyev, Y.

2011-12-01

Zonal jets observed in the oceans and atmospheres of planets are studied in a laboratory rotating tank. The fluid layer in the rotating tank has parabolic free surface and dynamically simulates the polar beta-plane where the Coriolis parameter varies quadratically with distance from the pole. Velocity and surface elevation fields are measured with an optical altimetry method (Afanasyev et al., Exps Fluids 2009). The flows are induced by a localized buoyancy source along radial direction. The baroclinic flow consisting of a field of eddies propagates away from the source due West and forms zonal jets (Fig. 1). Barotropic jets ahead of the baroclinic flow are formed by radiation of beta plumes. Inside the baroclinic flow the jets flow between the chains of eddies. Experimental evidence of so-called noodles (baroclinic instability mode with motions in the radial, North-South direction) theoretically predicted by Berloff et al. (JFM, JPO 2009) was found in our experiments. Beta plume radiation mechanism and the mechanism associated with the instability of noodles are likely to contribute to formation of jets in the baroclinic flow.

Conditioning Procedure for Spent Cs-137 Sealed Sources in Egypt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohamed, Y.T.; Hasan, M.A.; Lasheen, Y.F.

2006-07-01

It is the duty of the Hot Laboratories and Waste Management Center, Egyptian Atomic Energy Authority to mange the radioactive waste generated from any user for radioactive materials in Egypt. The most hazardous or dangerous radioactive waste we collect is spent radioactive sealed sources that have to be managed safely to protect human, workers and environment from any undue burden for radiation. Through the Integrated Management Program Of Radioactive Sealed Sources In Egypt, IMPRSS all spent Cs-137 sources with low activity will be retrievable conditioned in 200 L drum with special lead shield to keep the surface dose rate lowermore » than 200 merm/h according to US regulations and IAEA guidelines. Using this procedure the EAEA will condition about 243 sources in 9 drums. (authors)« less

Earthquake source properties from instrumented laboratory stick-slip

USGS Publications Warehouse

Kilgore, Brian D.; McGarr, Arthur F.; Beeler, Nicholas M.; Lockner, David A.; Thomas, Marion Y.; Mitchell, Thomas M.; Bhat, Harsha S.

2017-01-01

Stick-slip experiments were performed to determine the influence of the testing apparatus on source properties, develop methods to relate stick-slip to natural earthquakes and examine the hypothesis of McGarr [2012] that the product of stiffness, k, and slip duration, Δt, is scale-independent and the same order as for earthquakes. The experiments use the double-direct shear geometry, Sierra White granite at 2 MPa normal stress and a remote slip rate of 0.2 µm/sec. To determine apparatus effects, disc springs were added to the loading column to vary k. Duration, slip, slip rate, and stress drop decrease with increasing k, consistent with a spring-block slider model. However, neither for the data nor model is kΔt constant; this results from varying stiffness at fixed scale.In contrast, additional analysis of laboratory stick-slip studies from a range of standard testing apparatuses is consistent with McGarr's hypothesis. kΔt is scale-independent, similar to that of earthquakes, equivalent to the ratio of static stress drop to average slip velocity, and similar to the ratio of shear modulus to wavespeed of rock. These properties result from conducting experiments over a range of sample sizes, using rock samples with the same elastic properties as the Earth, and scale-independent design practices.

Development and deployment of the Collimated Directional Radiation Detection System

NASA Astrophysics Data System (ADS)

Guckes, Amber L.; Barzilov, Alexander

2017-09-01

The Collimated Directional Radiation Detection System (CDRDS) is capable of imaging radioactive sources in two dimensions (as a directional detector). The detection medium of the CDRDS is a single Cs2LiYCl6:Ce3+ scintillator cell enriched in 7Li (CLYC-7). The CLYC-7 is surrounded by a heterogeneous high-density polyethylene (HDPE) and lead (Pb) collimator. These materials make-up a coded aperture inlaid in the collimator. The collimator is rotated 360° by a stepper motor which enables time-encoded imaging of a radioactive source. The CDRDS is capable of spectroscopy and pulse shape discrimination (PSD) of photons and fast neutrons. The measurements of a radioactive source are carried out in discrete time steps that correlate to the angular rotation of the collimator. The measurement results are processed using a maximum likelihood expectation (MLEM) algorithm to create an image of the measured radiation. This collimator design allows for the directional detection of photons and fast neutrons simultaneously by utilizing only one CLYC-7 scintillator. Directional detection of thermal neutrons can also be performed by utilizing another suitable scintillator. Moreover, the CDRDS is portable, robust, and user friendly. This unit is capable of utilizing wireless data transfer for possible radiation mapping and network-centric applications. The CDRDS was tested by performing laboratory measurements with various gamma-ray and neutron sources.

Source of coherent short wavelength radiation

DOEpatents

Villa, Francesco

1990-01-01

An apparatus for producing coherent radiation ranging from X-rays to the far ultraviolet (i.e., 1 Kev to 10 eV) utilizing the Compton scattering effect. A photon beam from a laser is scattered on a high energy electron bunch from a pulse power linac. The short wavelength radiation produced by such scattering has sufficient intensity and spatial coherence for use in high resolution applications such as microscopy.

The EnzymeTracker: an open-source laboratory information management system for sample tracking.

PubMed

Triplet, Thomas; Butler, Gregory

2012-01-26

In many laboratories, researchers store experimental data on their own workstation using spreadsheets. However, this approach poses a number of problems, ranging from sharing issues to inefficient data-mining. Standard spreadsheets are also error-prone, as data do not undergo any validation process. To overcome spreadsheets inherent limitations, a number of proprietary systems have been developed, which laboratories need to pay expensive license fees for. Those costs are usually prohibitive for most laboratories and prevent scientists from benefiting from more sophisticated data management systems. In this paper, we propose the EnzymeTracker, a web-based laboratory information management system for sample tracking, as an open-source and flexible alternative that aims at facilitating entry, mining and sharing of experimental biological data. The EnzymeTracker features online spreadsheets and tools for monitoring numerous experiments conducted by several collaborators to identify and characterize samples. It also provides libraries of shared data such as protocols, and administration tools for data access control using OpenID and user/team management. Our system relies on a database management system for efficient data indexing and management and a user-friendly AJAX interface that can be accessed over the Internet. The EnzymeTracker facilitates data entry by dynamically suggesting entries and providing smart data-mining tools to effectively retrieve data. Our system features a number of tools to visualize and annotate experimental data, and export highly customizable reports. It also supports QR matrix barcoding to facilitate sample tracking. The EnzymeTracker was designed to be easy to use and offers many benefits over spreadsheets, thus presenting the characteristics required to facilitate acceptance by the scientific community. It has been successfully used for 20 months on a daily basis by over 50 scientists. The EnzymeTracker is freely available online at http

The EnzymeTracker: an open-source laboratory information management system for sample tracking

PubMed Central

2012-01-01

Background In many laboratories, researchers store experimental data on their own workstation using spreadsheets. However, this approach poses a number of problems, ranging from sharing issues to inefficient data-mining. Standard spreadsheets are also error-prone, as data do not undergo any validation process. To overcome spreadsheets inherent limitations, a number of proprietary systems have been developed, which laboratories need to pay expensive license fees for. Those costs are usually prohibitive for most laboratories and prevent scientists from benefiting from more sophisticated data management systems. Results In this paper, we propose the EnzymeTracker, a web-based laboratory information management system for sample tracking, as an open-source and flexible alternative that aims at facilitating entry, mining and sharing of experimental biological data. The EnzymeTracker features online spreadsheets and tools for monitoring numerous experiments conducted by several collaborators to identify and characterize samples. It also provides libraries of shared data such as protocols, and administration tools for data access control using OpenID and user/team management. Our system relies on a database management system for efficient data indexing and management and a user-friendly AJAX interface that can be accessed over the Internet. The EnzymeTracker facilitates data entry by dynamically suggesting entries and providing smart data-mining tools to effectively retrieve data. Our system features a number of tools to visualize and annotate experimental data, and export highly customizable reports. It also supports QR matrix barcoding to facilitate sample tracking. Conclusions The EnzymeTracker was designed to be easy to use and offers many benefits over spreadsheets, thus presenting the characteristics required to facilitate acceptance by the scientific community. It has been successfully used for 20 months on a daily basis by over 50 scientists. The EnzymeTracker is

Bibliography of marine radiation ecology prepared for the Seabed Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schultz, V.S.

1980-02-01

References on the effects of ionizing radiation on aquatic organisms have been obtained from a number of sources. Many were obtained from reviews and other publications. Although the primary purpose of preparing this bibliography was to obtain information related to the nuclear wastes Seabed Disposal Biology Program of Sandia Laboratories, freshwater organisms are included as a matter of convenience and also with the belief that such a bibliography would be of interest to a wider audience than that restricted to the Seabed Program. While compilation of a list in an area broad in scope is often somewhat arbitrary, an attemptmore » was made to reference publications that were related to field or laboratory studies of wild species of plants and animals with respect to radiation effects. Complete information concerning each reference are provided without excessive library search. Since one often finds references listed in the literature that are incompletely cited, it was not always possible to locate the reference for verification or completion of the citation. Such references are included where they appeared to be of possible value. When known, a reference is followed with its Nuclear Science Abstract designation, or rarely other abstract sources. Those desiring additional information should check Nuclear Science Abstracts utilizing the abstract number presented or other abstracting sources. In addition, the language of the article, other than English, is given when it is known to me.« less

Applications of Accelerators and Radiation Sources in the Field of Space Research and Industry.

PubMed

Campajola, Luigi; Di Capua, Francesco

2016-12-01

Beyond their important economic role in commercial communications, satellites in general are critical infrastructure because of the services they provide. In addition to satellites providing information which facilitates a better understanding of the space environment and improved performance of physics experiments, satellite observations are also used to actively monitor weather, geological processes, agricultural development and the evolution of natural and man-made hazards. Defence agencies depend on satellite services for communication in remote locations, as well as for reconnaissance and intelligence. Both commercial and government users rely on communication satellites to provide communication in the event of a disaster that damages ground-based communication systems, provide news, education and entertainment to remote areas and connect global businesses. The space radiation environment is an hazard to most satellite missions and can lead to extremely difficult operating conditions for all of the equipment travelling in space. Here, we first provide an overview of the main components of space radiation environment, followed by a description of the basic mechanism of the interaction of radiation with matter. This is followed by an introduction to the space radiation hardness assurance problem and the main effects of natural radiation to the microelectronics (total ionizing dose, displacement damage and the single-event effect and a description of how different effects occurring in the space can be tested in on-ground experiments by using particle accelerators and radiation sources. We also discuss standards and the recommended procedures to obtain reliable results.

A beam radiation monitor based on CVD diamonds for SuperB

NASA Astrophysics Data System (ADS)

Cardarelli, R.; Di Ciaccio, A.

2013-08-01

Chemical Vapor Deposition (CVD) diamond particle detectors are in use in the CERN experiments at LHC and at particle accelerator laboratories in Europe, USA and Japan mainly as beam monitors. Nowadays it is considered a proven technology with a very fast signal read-out and a very high radiation tolerance suitable for measurements in high radiation environment zones i.e. near the accelerators beam pipes. The specific properties of CVD diamonds make them a prime candidate for measuring single particles as well as high-intensity particle cascades, for timing measurements on the sub-nanosecond scale and for beam protection systems in hostile environments. A single-crystalline CVD (scCVD) diamond sensor, read out with a new generation of fast and high transition frequency SiGe bipolar transistor amplifiers, has been tested for an application as radiation monitor to safeguard the silicon vertex tracker in the SuperB detector from excessive radiation damage, cumulative dose and instantaneous dose rates. Test results with 5.5 MeV alpha particles from a 241Am radioactive source and from electrons from a 90Sr radioactive source are presented in this paper.

Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eigler, N.; Whiting, J.; Chernomorsky, A.

1998-01-16

RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Milliporemore » filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} over-the-wire, and TNT{trademark} rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors.« less

Proceedings of the First International Symposium on the Biological Interpretation of Dose from Accelerator-Produced Radiation, Held at the Lawrence Radiation Laboratory, Berkeley, California, March 13--16, 1967

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wallace, R.

1967-03-13

The objective of the meeting was to provide a companion meeting to the ''First Symposium on Accelerator Radiation Dosimetry and Experience'' which was held November 3-5, 1965, at the Brookhaven National Laboratory. This first symposium was limited in scope to an intensified discussion of dosimetry techniques. The biology which is associated with high energy radiation was specifically excluded, since it was the original plan to hold a second symposium devoted entirely to biology. Thus the present Symposium was a sequel to the first and they were inseparable in their objectives. Since those attending the BNL Symposium were almost entirely healthmore » physicists with a background in physical science and actively engaged in the solution of radiation protection problems at high energy accelerators, it was felt that it would be necessary to begin the BID Symposium with a general review session on radiation biology, in order to provide a biological background for the proper understanding of the later sessions. This first session was arranged to give the health physicist a meaningful transition from fundamental radiobiological considerations to current new research activities in high energy biology. In our opinion, and also based on the comments of several of those attending these objectives were quite well attained. The talks by Bond, Robertson, Brustad, Wolff, and Patt were quite exhaustive as an introduction to the several areas of specialization in radiobiology. The overall purpose of the meeting was of course to inform the health physicists about the state of knowledge in advanced biological research as it might apply to their problems. It has often been said that it takes a long time for laboratory findings to be applied in practical situations, but this is certainly not true in radiobiology. Through this conference and others like it, the most recent understanding of high energy radiobiology is available to the practicing health physicist and is probably used

Suggested design of gold-nanoobjects-based terahertz radiation source for biomedical research

NASA Astrophysics Data System (ADS)

Postnikov, A. V.; Moldosanov, K. A.

2018-07-01

Gold nanoparticles (GNPs) may serve as devices to emit electromagnetic radiation in the terahertz (THz) range, whereby the energy is delivered by radio frequency or microwave photons which will not by themselves induce transitions between sparse confinement-shaped electron levels of a GNP, but may borrow the energy from longitudinal acoustic (LA) phonons to overcome the confinement gap. Upon excitation, the Fermi electron cannot relax otherwise than via emitting a THz photon, the other relaxation channels being blocked by force of shape and size considerations. Within this general scope that has already been outlined earlier, the present work specifically discusses two-phonon processes, namely (i) a combined absorption–emission of two phonons from the top of the LA branch, and (ii) an absorption of two such phonons with nearly identical wavevectors. The case (i) may serve as a source of soft THz radiation (at ≃0.54 THz), the case (ii) the hard THz radiation at 8.7 THz. Numerical estimates are done for crystalline particles in the shape of rhombicuboctahedra, of 5–7 nm size. A technical realisation of this idea is briefly discussed, assuming the deposition of GNPs onto/within the substrate of Teflon®, the material sustaining high temperatures and transparent in the THz range.

Suggested design of gold-nanoobjects-based terahertz radiation source for biomedical research.

PubMed

Postnikov, A V; Moldosanov, K A

2018-04-18

Gold nanoparticles (GNPs) may serve as devices to emit electromagnetic radiation in the terahertz (THz) range, whereby the energy is delivered by radio frequency or microwave photons which will not by themselves induce transitions between sparse confinement-shaped electron levels of a GNP, but may borrow the energy from longitudinal acoustic (LA) phonons to overcome the confinement gap. Upon excitation, the Fermi electron cannot relax otherwise than via emitting a THz photon, the other relaxation channels being blocked by force of shape and size considerations. Within this general scope that has already been outlined earlier, the present work specifically discusses two-phonon processes, namely (i) a combined absorption-emission of two phonons from the top of the LA branch, and (ii) an absorption of two such phonons with nearly identical wavevectors. The case (i) may serve as a source of soft THz radiation (at ≃0.54 THz), the case (ii) the hard THz radiation at 8.7 THz. Numerical estimates are done for crystalline particles in the shape of rhombicuboctahedra, of 5-7 nm size. A technical realisation of this idea is briefly discussed, assuming the deposition of GNPs onto/within the substrate of Teflon ® , the material sustaining high temperatures and transparent in the THz range.

3D Printing in the Laboratory: Maximize Time and Funds with Customized and Open-Source Labware.

PubMed

Coakley, Meghan; Hurt, Darrell E

2016-08-01

3D printing, also known as additive manufacturing, is the computer-guided process of fabricating physical objects by depositing successive layers of material. It has transformed manufacturing across virtually every industry, bringing about incredible advances in research and medicine. The rapidly growing consumer market now includes convenient and affordable "desktop" 3D printers. These are being used in the laboratory to create custom 3D-printed equipment, and a growing community of designers are contributing open-source, cost-effective innovations that can be used by both professionals and enthusiasts. User stories from investigators at the National Institutes of Health and the biomedical research community demonstrate the power of 3D printing to save valuable time and funding. While adoption of 3D printing has been slow in the biosciences to date, the potential is vast. The market predicts that within several years, 3D printers could be commonplace within the home; with so many practical uses for 3D printing, we anticipate that the technology will also play an increasingly important role in the laboratory. © 2016 Society for Laboratory Automation and Screening.

MICROBIAL LABORATORY GUIDANCE MANUAL FOR THE ...

EPA Pesticide Factsheets

The Long-Term 2 Enhanced Surface Water Treatment Rule Laboratory Instruction Manual will be a compilation of all information needed by laboratories and field personnel to collect, analyze, and report the microbiological data required under the rule. The manual will provide laboratories with a single source of information that currently is available from various sources including the latest versions of Methods 1622 and 1623, including all approved, equivalent modifications; the procedures for E.coli methods approved for use under the LT2ESWTR; lists of vendor sources; data recording forms; data reporting requirements; information on the Laboratory Quality Assurance Evaluation Program for the Analysis of Cryptosporidium in Water; and sample collection procedures. Although most of this information is available elsewhere, a single, comprehensive compendium containing this information is needed to aid utilities and laboratories performing the sampling and analysis activities required under the LT2 rule. This manual will serve as an instruction manual for laboratories to use when collecting data for Crypto, E. coli and turbidity.

Thirty-sixth Lauriston S. Taylor Lecture on radiation protection and measurements--from the field to the laboratory and back: the what ifs, wows, and who cares of radiation biology.

PubMed

Brooks, Antone L

2013-11-01

My scientific journey started at the University of Utah chasing fallout. It was on everything, in everything, and was distributed throughout the ecosystem. This resulted in radiation doses to humans and caused me great concern. From this concern I asked the question, "Are there health effects from these radiation doses and levels of radioactive contamination?" I have invested my scientific career trying to address this basic question. While conducting research, I got acquainted with many of the What ifs of radiation biology. The major What if in my research was, "What if we have underestimated the radiation risk for internally-deposited radioactive material?" While conducting research to address this important question, many other What ifs came up related to dose, dose rate, and dose distribution. I also encountered a large number of Wows. One of the first was when I went from conducting environmental fallout studies to research in a controlled laboratory. The activity in fallout was expressed as pCi L⁻¹, whereas it was necessary to inject laboratory animals with μCi g⁻¹ body weight to induce measurable biological changes, chromosome aberrations, and cancer. Wow! That is seven to nine orders of magnitude above the activity levels found in the environment. Other Wows have made it necessary for the field of radiation biology to make important paradigm shifts. For example, one shift involved changing from "hit theory" to total tissue responses as the result of bystander effects. Finally, Who cares? While working at U.S. Department of Energy headquarters and serving on many scientific committees, I found that science does not drive regulatory and funding decisions. Public perception and politics seem to be major driving forces. If scientific data suggested that risk had been underestimated, everyone cared. When science suggested that risk had been overestimated, no one cared. This result-dependent Who cares? was demonstrated as we tried to generate interactions

Laboratory investigation of flux reduction from dense non-aqueous phase liquid (DNAPL) partial source zone remediation by enhanced dissolution

NASA Astrophysics Data System (ADS)

Kaye, Andrew J.; Cho, Jaehyun; Basu, Nandita B.; Chen, Xiaosong; Annable, Michael D.; Jawitz, James W.

2008-11-01

This study investigated the benefits of partial removal of dense nonaqueous phase liquid (DNAPL) source zones using enhanced dissolution in eight laboratory scale experiments. The benefits were assessed by characterizing the relationship between reductions in DNAPL mass and the corresponding reduction in contaminant mass flux. Four flushing agents were evaluated in eight controlled laboratory experiments to examine the effects of displacement fluid property contrasts and associated override and underride on contaminant flux reduction ( Rj) vs. mass reduction ( Rm) relationships ( Rj( Rm)): 1) 50% ethanol/50% water (less dense than water), 2) 40% ethyl-lactate/60% water (more dense than water), 3) 18% ethanol/26% ethyl-lactate/56% water (neutrally buoyant), and 4) 2% Tween-80 surfactant (also neutrally buoyant). For each DNAPL architecture evaluated, replicate experiments were conducted where source zone dissolution was conducted with a single flushing event to remove most of the DNAPL from the system, and with multiple shorter-duration floods to determine the path of the Rj( Rm) relationship. All of the single-flushing experiments exhibited similar Rj( Rm) relationships indicating that override and underride effects associated with cosolvents did not significantly affect the remediation performance of the agents. The Rj( Rm) relationship of the multiple injection experiments for the cosolvents with a density contrast with water tended to be less desirable in the sense that there was less Rj for a given Rm. UTCHEM simulations supported the observations from the laboratory experiments and demonstrated the capability of this model to predict Rj( Rm) relationships for non-uniformly distributed NAPL sources.

Initial experiments to understand the interaction of stellar radiation with molecular clouds

NASA Astrophysics Data System (ADS)

Vandervort, Robert; Davis, Josh; Trantham, Matt; Klein, Sallee; Shvarts, Dov; Keiter, Paul; Drake, R. Paul

2017-10-01

Enhanced star formation triggered by local O and B type stars is an astrophysical problem of interest. O and B type stars are massive, hot stars that emit an enormous amount of radiation. This radiation acts to either compress or blow apart gas clumps in the interstellar media. For example, in the optically thick limit, when the radiation in the gas clump has a short mean free path, radiation is absorbed near the clump edge and compresses the clump. In the optically thin limit, when the mean free path is long, the radiation is absorbed throughout, acting to heat the clump. This heating explodes the gas clump. Careful selection of parameters, such as foam density or source temperature, allow the experimental platform to access different hydrodynamic regimes. 2D CRASH simulations guide our parameter selection. A stellar radiation source is mimicked by a laser-irradiated, thin, gold foil, providing a source of thermal x-rays around 100 eV. The gas clump is mimicked by low-density CRF foam. We plan to show the preliminary experimental results of this platform in the optically thick limit, from experiments scheduled in August. This work is funded by the U.S. DOE, through the NNSA-DS and SC-OFES Joint Program in HEDPLP, Grant No. DE-NA0002956, and the NLUF Program, Grant No. DE-NA0002719, and through LLE, University of Rochester by the NNSA/OICF under Cooperative Agreement No. DE-NA0001944. This work is funded by the Lawrence Livermore National Laboratory under subcontract B614207.

Numerical modeling of a point-source image under relative motion of radiation receiver and atmosphere

NASA Astrophysics Data System (ADS)

Kucherov, A. N.; Makashev, N. K.; Ustinov, E. V.

1994-02-01

A procedure is proposed for numerical modeling of instantaneous and averaged (over various time intervals) distant-point-source images perturbed by a turbulent atmosphere that moves relative to the radiation receiver. Examples of image calculations under conditions of the significant effect of atmospheric turbulence in an approximation of geometrical optics are presented and analyzed.

Laboratory Simulation of Frozen Methanol Under X-ray Radiation Field: Relevancies to Astrophysical Ices

NASA Astrophysics Data System (ADS)

Andrade, Diana; Rocco, Maria Luiza M.; Boechat-Roberty, Heloisa Maria

The origin of complex organic molecules detected in comets, meteorites, star-forming regions and other environments are currently subject of discussion. Depending on the environment, it is dominated by X-rays, UV photons as well as by charged particles, electrons and ions with high or low energies. Every particle will promote a different fragmentation in the molecule and different phenomena in the ice, favoring the formation of an ion species rather than another. To predict the chemical evolution and to quantify the complex organics incorporated into grains or desorbed to the gas phase, it is necessary to establish the main formation route, which can be tested in the laboratories. In this way, the study of the effects of different ionization agents on the ices becomes crucial. Methanol (CH3 OH), the simplest organic alcohol, is an important precursor of more complex prebiotic species and is found abundantly in icy mantles on interstellar and protostellar dust grains. This molecule has been detected through infrared spectroscopy in some astrophysics environments as W33A and RAFGL 7009. Additionally, methanol has been found in comets, as Hale-Bopp, and other solar system bodies, such as the centaur 5145 Pholus. All of these astronomical environments are subjected to some form of ionizing agents such as cosmic rays, electrons and photons (e.g. stellar radiation field). In this work, synchrotron radiation from the Brazilian Synchrotron Light Laboratory at the O 1s-edge was employed to perform desorption experiments on the frozen methanol. The desorp-tion rates (desorbed ion per incident photon) of the most intense ions desorbed from methanol due soft X-ray bombardment are estimated. The desorption rates are critical parameters for modeling the chemistry of interstellar clouds. Moreover, a comparison among our results and literature using different ionization agents and different phases (photons at 292 eV and elec-trons at 70 eV in gaseous phase and heavy ions around 65

An improved radiation metric. [for radiation pressure in strong gravitational fields

NASA Technical Reports Server (NTRS)

Noerdlinger, P. D.

1976-01-01

An improved radiation metric is obtained in which light rays make a small nonzero angle with the radius, thus representing a source of finite size. Kaufmann's previous solution is criticized. The stabilization of a scatterer near a source of gravitational field and radiation is slightly enhanced for sources of finite size.

Development of 2D imaging of SXR plasma radiation by means of GEM detectors

NASA Astrophysics Data System (ADS)

Chernyshova, M.; Czarski, T.; Jabłoński, S.; Kowalska-Strzeciwilk, E.; Poźniak, K.; Kasprowicz, G.; Zabołotny, W.; Wojeński, A.; Byszuk, A.; Burza, M.; Juszczyk, B.; Zienkiewicz, P.

2014-11-01

Presented 2D gaseous detector system has been developed and designed to provide energy resolved fast dynamic plasma radiation imaging in the soft X-Ray region with 0.1 kHz exposure frequency for online, made in real time, data acquisition (DAQ) mode. The detection structure is based on triple Gas Electron Multiplier (GEM) amplification structure followed by the pixel readout electrode. The efficiency of detecting unit was adjusted for the radiation energy region of tungsten in high-temperature plasma, the main candidate for the plasma facing material for future thermonuclear reactors. Here we present preliminary laboratory results and detector parameters obtained for the developed system. The operational characteristics and conditions of the detector were designed to work in the X-Ray range of 2-17 keV. The detector linearity was checked using the fluorescence lines of different elements and was found to be sufficient for good photon energy reconstruction. Images of two sources through various screens were performed with an X-Ray laboratory source and 55Fe source showing a good imaging capability. Finally offline stream-handling data acquisition mode has been developed for the detecting system with timing down to the ADC sampling frequency rate (~13 ns), up to 2.5 MHz of exposure frequency, which could pave the way to invaluable physics information about plasma dynamics due to very good time resolving ability. Here we present results of studied spatial resolution and imaging properties of the detector for conditions of laboratory moderate counting rates and high gain.

Novel particle and radiation sources and advanced materials

NASA Astrophysics Data System (ADS)

Mako, Frederick

2016-03-01

The influence Norman Rostoker had on the lives of those who had the pleasure of knowing him is profound. The skills and knowledge I gained as a graduate student researching collective ion acceleration has fueled a career that has evolved from particle beam physics to include particle and radiation source development and advanced materials research, among many other exciting projects. The graduate research performed on collective ion acceleration was extended by others to form the backbone for laser driven plasma ion acceleration. Several years after graduate school I formed FM Technologies, Inc., (FMT), and later Electron Technologies, Inc. (ETI). Currently, as the founder and president of both FMT and ETI, the Rostoker influence can still be felt. One technology that we developed is a self-bunching RF fed electron gun, called the Micro-Pulse Gun (MPG). The MPG has important applications for RF accelerators and microwave tube technology, specifically clinically improved medical linacs and "green" klystrons. In addition to electron beam and RF source research, knowledge of materials and material interactions gained indirectly in graduate school has blossomed into breakthroughs in materials joining technologies. Most recently, silicon carbide joining technology has been developed that gives robust helium leak tight, high temperature and high strength joints between ceramic-to-ceramic and ceramic-to-metal. This joining technology has the potential to revolutionize the ethylene production, nuclear fuel and solar receiver industries by finally allowing for the practical use of silicon carbide as furnace coils, fuel rods and solar receptors, respectively, which are applications that have been needed for decades.

Laboratory-Produced X-Ray Photoionized Plasmas for Astrophysics Exploration

NASA Astrophysics Data System (ADS)

Goyon, Clement; Le Pape, Sebastien; Liedahl, Duane; Ma, Tammy; Berzak-Hopkins, Laura; Reverdin, Charles; Rousseaux, Christophe; Renaudin, Patrick; Blancard, Christophe; Nottet, Edouard; Bidault, Niels; Mancini, Roberto; Koenig, Michel

2015-11-01

X-ray photoionized plasmas are rare in the laboratory, but of broad importance in astrophysical objects such as active galactic nuclei, x-ray binaries. Indeed, existing models are not yet able to accurately describe these plasmas where ionization is driven by radiation rather than electron collisions. Here, we describe an experiment on the LULI2000 facility whose versatility allows for measuring the X-ray absorption of the plasma while independently probing its electron density and temperature. The bright X-ray source is created by the two main beams focused inside a gold hohlraum and is used to photoionise a Neon gas jet. Then, a thin gold foil serves as a source of backlit photons for absorption spectroscopy. The transmitted spectrum through the plasma is collected by a crystal spectrometer. We will present the experimental setup used to characterize both plasma conditions and X-ray emission. Then we will show the transmitted spectra through the plasma to observe the transition from collision dominated to radiation dominated ionization and compare it to model predictions. This work was performed under the auspices of the U.S.Department of Energy by Lawrence Livermore Natl Lab under Contract No. DE-AC52-07NA27344.

Conditioning of the 4 Curies Radium-226 Sealed Radiation Source in Thailand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Punnachaiya, M.; Sawangsri, T.; Wanabongse, P.

This paper describes the conditioning of the 4 curies Radium-226 (Ra-226) sealed radiation source using as a teletherapy unit for cancer treatment in Thailand. The conditioning was under the International Atomic Energy Agency (IAEA) supervision and budgetary supports, comprised of 6 operational steps: the surface dose rate and actual dimension of radium unit measurements, the appropriate lead shielding design with IAEA approval, confirmation of radioactive contamination before conditioning (smear test and radon gas leakage test), transfer of radium source unit into the designed shielding, confirmation of radioactive contamination and dose rate measurement after conditioning, and transportation of Ra-226 conditioning wastemore » package to OAP interim waste storage. The Ra-226 unit was taken out of OAP temporary waste storage for the surface dose rate and the actual dimension measurements behind the 12 inches thick heavy concrete shielding. The maximum measured surface dose rate was 70 R/hr. The special lead container was designed according to its surface dose rate along the source unit which the maximum permissible dose limit for surface dose rate of waste package after conditioning at 2 mSv/hr was applied. The IAEA approved container had total weight of 2.4 ton. After the confirmation of radioactive contamination, Ra-226 source unit was transferred and loaded in the designed lead shielding within 2 minutes. The results of smear test before and after conditioning including radon gas leakage test revealed that there was no radioactive contamination. After conditioning, the surface dose rate measured on the top, bottom were 15,10 mR/hr and varied from 6 - 50 mR/hr around lead container. The Ra-226 conditioning waste package was safely transported to store in OAP interim waste storage. Total working time including the time consumed for radon gas leakage test was 3.5 hours. The total radiation dose received by 16 operators, were ranged from 1 - 69.84 {mu}Sv and the

Propagation-based phase-contrast tomography for high-resolution lung imaging with laboratory sources

NASA Astrophysics Data System (ADS)

Krenkel, Martin; Töpperwien, Mareike; Dullin, Christian; Alves, Frauke; Salditt, Tim

2016-03-01

We have performed high-resolution phase-contrast tomography on whole mice with a laboratory setup. Enabled by a high-brilliance liquid-metal-jet source, we show the feasibility of propagation-based phase contrast in local tomography even in the presence of strongly absorbing surrounding tissue as it is the case in small animal imaging of the lung. We demonstrate the technique by reconstructions of the mouse lung for two different fields of view, covering the whole organ, and a zoom to the local finer structure of terminal airways and alveoli. With a resolution of a few micrometers and the wide availability of the technique, studies of larger biological samples at the cellular level become possible.

Complete Sets of Radiating and Nonradiating Parts of a Source and Their Fields with Applications in Inverse Scattering Limited-Angle Problems

PubMed Central

Louis, A. K.

2006-01-01

Many algorithms applied in inverse scattering problems use source-field systems instead of the direct computation of the unknown scatterer. It is well known that the resulting source problem does not have a unique solution, since certain parts of the source totally vanish outside of the reconstruction area. This paper provides for the two-dimensional case special sets of functions, which include all radiating and all nonradiating parts of the source. These sets are used to solve an acoustic inverse problem in two steps. The problem under discussion consists of determining an inhomogeneous obstacle supported in a part of a disc, from data, known for a subset of a two-dimensional circle. In a first step, the radiating parts are computed by solving a linear problem. The second step is nonlinear and consists of determining the nonradiating parts. PMID:23165060

Synchrotron Radiation Research--An Overview.

ERIC Educational Resources Information Center

Bienenstock, Arthur; Winick, Herman

1983-01-01

Discusses expanding user community seeking access to synchrotron radiation sources, properties/sources of synchrotron radiation, permanent-magnet technology and its impact on synchrotron radiation research, factors limiting power, the density of synchrotron radiation, and research results illustrating benefit of higher flux and brightness. Also…

Laser-produced lithium plasma as a narrow-band extended ultraviolet radiation source for photoelectron spectroscopy.

PubMed

Schriever, G; Mager, S; Naweed, A; Engel, A; Bergmann, K; Lebert, R

1998-03-01

Extended ultraviolet (EUV) emission characteristics of a laser-produced lithium plasma are determined with regard to the requirements of x-ray photoelectron spectroscopy. The main features of interest are spectral distribution, photon flux, bandwidth, source size, and emission duration. Laser-produced lithium plasmas are characterized as emitters of intense narrow-band EUV radiation. It can be estimated that the lithium Lyman-alpha line emission in combination with an ellipsoidal silicon/molybdenum multilayer mirror is a suitable EUV source for an x-ray photoelectron spectroscopy microscope with a 50-meV energy resolution and a 10-mum lateral resolution.

Dental Laboratory Technology.

ERIC Educational Resources Information Center

Department of the Air Force, Washington, DC.

The Air Force dental laboratory technology manual is designed as a basic training text as well as a reference source for dental laboratory technicians, a specialty occupation concerned with the design, fabrication, and repair of dental prostheses. Numerous instructive diagrams and photographs are included throughout the manual. The comprehensive…

The influence of high intensity terahertz radiation on mammalian cell adhesion, proliferation and differentiation.

PubMed

Williams, Rachel; Schofield, Amy; Holder, Gareth; Downes, Joan; Edgar, David; Harrison, Paul; Siggel-King, Michele; Surman, Mark; Dunning, David; Hill, Stephen; Holder, David; Jackson, Frank; Jones, James; McKenzie, Julian; Saveliev, Yuri; Thomsen, Neil; Williams, Peter; Weightman, Peter

2013-01-21

Understanding the influence of exposure of biological systems to THz radiation is becoming increasingly important. There is some evidence to suggest that THz radiation can influence important activities within mammalian cells. This study evaluated the influence of the high peak power, low average power THz radiation produced by the ALICE (Daresbury Laboratory, UK) synchrotron source on human epithelial and embryonic stem cells. The cells were maintained under standard tissue culture conditions, during which the THz radiation was delivered directly into the incubator for various exposure times. The influence of the THz radiation on cell morphology, attachment, proliferation and differentiation was evaluated. The study demonstrated that there was no difference in any of these parameters between irradiated and control cell cultures. It is suggested that under these conditions the cells are capable of compensating for any effects caused by exposure to THz radiation with the peak powers levels employed in these studies.

Laboratory safety handbook

USGS Publications Warehouse

Skinner, E.L.; Watterson, C.A.; Chemerys, J.C.

1983-01-01

Safety, defined as 'freedom from danger, risk, or injury,' is difficult to achieve in a laboratory environment. Inherent dangers, associated with water analysis and research laboratories where hazardous samples, materials, and equipment are used, must be minimized to protect workers, buildings, and equipment. Managers, supervisors, analysts, and laboratory support personnel each have specific responsibilities to reduce hazards by maintaining a safe work environment. General rules of conduct and safety practices that involve personal protection, laboratory practices, chemical handling, compressed gases handling, use of equipment, and overall security must be practiced by everyone at all levels. Routine and extensive inspections of all laboratories must be made regularly by qualified people. Personnel should be trained thoroughly and repetitively. Special hazards that may involve exposure to carcinogens, cryogenics, or radiation must be given special attention, and specific rules and operational procedures must be established to deal with them. Safety data, reference materials, and texts must be kept available if prudent safety is to be practiced and accidents prevented or minimized.

Correct consideration of the index of refraction using blackbody radiation.

PubMed

Hartmann, Jurgen

2006-09-04

The correct consideration of the index of refraction when using blackbody radiators as standard sources for optical radiation is derived and discussed. It is shown that simply using the index of refraction of air at laboratory conditions is not sufficient. A combination of the index of refraction of the media used inside the blackbody radiator and for the optical path between blackbody and detector has to be used instead. A worst case approximation for the introduced error when neglecting these effects is presented, showing that the error is below 0.1 % for wavelengths above 200 nm. Nevertheless, for the determination of the spectral radiance for the purpose of radiation temperature measurements the correct consideration of the refractive index is mandatory. The worst case estimation reveals that the introduced error in temperature at a blackbody temperature of 3000 degrees C can be as high as 400 mk at a wavelength of 650 nm and even higher at longer wavelengths.

Error sources in the real-time NLDAS incident surface solar radiation and an evaluation against field observations and the NARR

NASA Astrophysics Data System (ADS)

Park, G.; Gao, X.; Sorooshian, S.

2005-12-01

The atmospheric model is sensitive to the land surface interactions and its coupling with Land surface Models (LSMs) leads to a better ability to forecast weather under extreme climate conditions, such as droughts and floods (Atlas et al. 1993; Beljaars et al. 1996). However, it is still questionable how accurately the surface exchanges can be simulated using LSMs, since terrestrial properties and processes have high variability and heterogeneity. Examinations with long-term and multi-site surface observations including both remotely sensed and ground observations are highly needed to make an objective evaluation on the effectiveness and uncertainty of LSMs at different circumstances. Among several atmospheric forcing required for the offline simulation of LSMs, incident surface solar radiation is one of the most significant components, since it plays a major role in total incoming energy into the land surface. The North American Land Data Assimilation System (NLDAS) and North American Regional Reanalysis (NARR) are two important data sources providing high-resolution surface solar radiation data for the use of research communities. In this study, these data are evaluated against field observations (AmeriFlux) to identify their advantages, deficiencies and sources of errors. The NLDAS incident solar radiation shows a pretty good agreement in monthly mean prior to the summer of 2001, while it overestimates after the summer of 2001 and its bias is pretty close to the EDAS. Two main error sources are identified: 1) GOES solar radiation was not used in the NLDAS for several months in 2001 and 2003, and 2) GOES incident solar radiation when available, was positively biased in year 2002. The known snow detection problem is sometimes identified in the NLDAS, since it is inherited from GOES incident solar radiation. The NARR consistently overestimates incident surface solar radiation, which might produce erroneous outputs if used in the LSMs. Further attention is given to

Quantifying sources of bias in National Healthcare Safety Network laboratory-identified Clostridium difficile infection rates.

PubMed

Haley, Valerie B; DiRienzo, A Gregory; Lutterloh, Emily C; Stricof, Rachel L

2014-01-01

To assess the effect of multiple sources of bias on state- and hospital-specific National Healthcare Safety Network (NHSN) laboratory-identified Clostridium difficile infection (CDI) rates. Sensitivity analysis. A total of 124 New York hospitals in 2010. New York NHSN CDI events from audited hospitals were matched to New York hospital discharge billing records to obtain additional information on patient age, length of stay, and previous hospital discharges. "Corrected" hospital-onset (HO) CDI rates were calculated after (1) correcting inaccurate case reporting found during audits, (2) incorporating knowledge of laboratory results from outside hospitals, (3) excluding days when patients were not at risk from the denominator of the rates, and (4) adjusting for patient age. Data sets were simulated with each of these sources of bias reintroduced individually and combined. The simulated rates were compared with the corrected rates. Performance (ie, better, worse, or average compared with the state average) was categorized, and misclassification compared with the corrected data set was measured. Counting days patients were not at risk in the denominator reduced the state HO rate by 45% and resulted in 8% misclassification. Age adjustment and reporting errors also shifted rates (7% and 6% misclassification, respectively). Changing the NHSN protocol to require reporting of age-stratified patient-days and adjusting for patient-days at risk would improve comparability of rates across hospitals. Further research is needed to validate the risk-adjustment model before these data should be used as hospital performance measures.

Influence of Extraterrestrial Radiation on Radiation Portal Monitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keller, Paul E.; Kouzes, Richard T.

2009-06-01

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 activitymore » 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.« less

Influence of ambient meteorology on the accuracy of radiation measurements: insights from field and laboratory experiments

NASA Astrophysics Data System (ADS)

Oswald, Sandro M.; Pietsch, Helga; Baumgartner, Dietmar J.; Rieder, Harald E.

2016-04-01

A precise knowledge of the surface energy budget, which includes the solar and terrestrial radiation fluxes, is needed to accurately characterize the global energy balance which is largely determining Earth's climate. To this aim national and global monitoring networks for surface radiative fluxes have been established in recent decades. The most prominent among these networks is the so-called Baseline Surface Radiation Network (BSRN) operating under the auspices of the World Climate Research Programme (WCRP) (Ohmura et al., 1998). National monitoring networks such as the Austrian RADiation Monitoring Network (ARAD), which has been established in 2010 by a consortium of the Central Agency of Meteorology and Geodynamics (ZAMG), the University of Graz, the University of Innsbruck, and the University of Natural Resources and Applied Sciences, Vienna (BOKU), orient themselves on BSRN standards (McArthur, 2005). ARAD comprises to date five sites (Wien Hohe Warte, Graz/University, Innsbruck/University, Kanzelhöhe Observatory and Sonnblick (which is also a BSRN site)) and aims to provide long-term monitoring of radiation budget components at highest accuracy and to capture the spatial patterns of radiation climate in Austria (Olefs et al., 2015). Given the accuracy requirement for the local monitoring of radiative fluxes instrument offsets, triggered by meteorological factors and/or instrumentation, pose a major challenge in radiation monitoring. Within this study we investigate effects of ambient meteorology on the accuracy of radiation measurements performed with pyranometers contained in various heating/ventilation systems (HV-systems), all of which used in regular operation within the ARAD network. We focus particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation we performed a series of controlled laboratory experiments as well as targeted field campaigns in 2015 and 2016. Our results indicate

PTB’s radiometric scales for UV and VUV source calibration based on synchrotron radiation

NASA Astrophysics Data System (ADS)

Klein, Roman; Kroth, Simone; Paustian, Wolfgang; Richter, Mathias; Thornagel, Reiner

2018-06-01

The radiant intensity of synchrotron radiation can be accurately calculated with classical electrodynamics. This primary realization of the spectral radiant intensity has been used by PTB at several electron storage rings which have been optimized to be operated as primary source standards for the calibration of transfer sources in the spectral range of UV and VUV for almost 30 years. The transfer sources are compared to the primary source standard by means of suitable wavelength-dispersive transfer stations. The spectral range covered by deuterium lamps, which represent transfer sources that are easy to handle, is of particular relevance in practice. Here, we report on developments in the realization and preservation of the radiometric scales for spectral radiant intensity and spectral radiance in the wavelength region from 116 nm to 400 nm, based on a set of deuterium reference lamps, over the last few decades. An inside view and recommendations on the operation of the D2 lamps used for the realization of the radiometric scale are presented. The data has been recently compiled to illustrate the chronological behaviour at various wavelengths. Moreover, an overview of the internal and external validation measurements and intercomparisons is given.

Laboratory investigation of flux reduction from dense non-aqueous phase liquid (DNAPL) partial source zone remediation by enhanced dissolution.

PubMed

Kaye, Andrew J; Cho, Jaehyun; Basu, Nandita B; Chen, Xiaosong; Annable, Michael D; Jawitz, James W

2008-11-14

This study investigated the benefits of partial removal of dense nonaqueous phase liquid (DNAPL) source zones using enhanced dissolution in eight laboratory scale experiments. The benefits were assessed by characterizing the relationship between reductions in DNAPL mass and the corresponding reduction in contaminant mass flux. Four flushing agents were evaluated in eight controlled laboratory experiments to examine the effects of displacement fluid property contrasts and associated override and underride on contaminant flux reduction (R(j)) vs. mass reduction (R(m)) relationships (R(j)(R(m))): 1) 50% ethanol/50% water (less dense than water), 2) 40% ethyl-lactate/60% water (more dense than water), 3) 18% ethanol/26% ethyl-lactate/56% water (neutrally buoyant), and 4) 2% Tween-80 surfactant (also neutrally buoyant). For each DNAPL architecture evaluated, replicate experiments were conducted where source zone dissolution was conducted with a single flushing event to remove most of the DNAPL from the system, and with multiple shorter-duration floods to determine the path of the R(j)(R(m)) relationship. All of the single-flushing experiments exhibited similar R(j)(R(m)) relationships indicating that override and underride effects associated with cosolvents did not significantly affect the remediation performance of the agents. The R(j)(R(m)) relationship of the multiple injection experiments for the cosolvents with a density contrast with water tended to be less desirable in the sense that there was less R(j) for a given R(m). UTCHEM simulations supported the observations from the laboratory experiments and demonstrated the capability of this model to predict R(j)(R(m)) relationships for non-uniformly distributed NAPL sources.

Annual environmental monitoring report of the Lawrence Berkeley Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schleimer, G.E.

1989-06-01

The Environmental Monitoring Program of the Lawrence Berkeley Laboratory (LBL) is described. Data for 1988 are presented and general trends are discussed. In order to establish whether LBL research activities produced any impact on the population surrounding the laboratory, a program of environmental air and water sampling and continuous radiation monitoring was carried on throughout the year. For 1988, as in the previous several years, dose equivalents attributable to LBL radiological operations were a small fraction of both the relevant radiation protection guidelines (RPG) and of the natural radiation background. 16 refs., 7 figs., 21 tabs.

Laboratory longevity and competitiveness of Dacus ciliatus Loew (Diptera: Tephritidae) following sub-sterilizing gamma irradiation.

PubMed

Nemny-Lavy, E; Nestel, D; Rempoulakis, P

2016-06-01

The effect of a sub-sterilizing gamma radiation dose on Dacus ciliatus adults was investigated to assess the suitability of the sterile insect technique (SIT) as an alternative method to control this pest. Late pupae (48 h prior to adult emergence) from a laboratory strain were irradiated with 120 Gy of gamma rays emitted by a 60Co source. Following adult emergence, the mortality of irradiated and non-irradiated cohorts was recorded. Over a period of 50 days after emergence, no significant negative effects of irradiation upon the longevity of male or female laboratory flies were observed. A laboratory competitiveness study (Fried test), using irradiated laboratory and wild males at a ratio of 3:1 was conducted to assess the ability of irradiated males to reduce the egg hatch rates of a wild population. The overall competitiveness was found to be ca. 0.32, suggesting a reduced, but satisfactory, quality of irradiated laboratory as compared with wild males. Based on the above findings, we calculated and proposed effective male release ratios for field application of SIT against D. ciliatus.

"Do-It-Yourself" reliable pH-stat device by using open-source software, inexpensive hardware and available laboratory equipment

PubMed Central

Kragic, Rastislav; Kostic, Mirjana

2018-01-01

In this paper, we present the construction of a reliable and inexpensive pH stat device, by using open-source “OpenPhControl” software, inexpensive hardware (a peristaltic and a syringe pump, Arduino, a step motor…), readily available laboratory devices: a pH meter, a computer, a webcam, and some 3D printed parts. We provide a methodology for the design, development and test results of each part of the device, as well as of the entire system. In addition to dosing reagents by means of a low-cost peristaltic pump, we also present carefully controlled dosing of reagents by an open-source syringe pump. The upgrading of the basic open-source syringe pump is given in terms of pump control and application of a larger syringe. In addition to the basic functions of pH stat, i.e. pH value measurement and maintenance, an improvement allowing the device to be used for potentiometric titration has been made as well. We have demonstrated the device’s utility when applied for cellulose fibers oxidation with 2,2,6,6-tetramethylpiperidine-1-oxyl radical, i.e. for TEMPO-mediated oxidation. In support of this, we present the results obtained for the oxidation kinetics, the consumption of added reagent and experimental repeatability. Considering that the open-source scientific tools are available to everyone, and that researchers can construct and adjust the device according to their needs, as well as, that the total cost of the open-source pH stat device, excluding the existing laboratory equipment (pH meter, computer and glossary) was less than 150 EUR, we believe that, at a small fraction of the cost of available commercial offers, our open-source pH stat can significantly improve experimental work where the use of pH stat is necessary. PMID:29509793

"Do-It-Yourself" reliable pH-stat device by using open-source software, inexpensive hardware and available laboratory equipment.

PubMed

Milanovic, Jovana Z; Milanovic, Predrag; Kragic, Rastislav; Kostic, Mirjana

2018-01-01

In this paper, we present the construction of a reliable and inexpensive pH stat device, by using open-source "OpenPhControl" software, inexpensive hardware (a peristaltic and a syringe pump, Arduino, a step motor…), readily available laboratory devices: a pH meter, a computer, a webcam, and some 3D printed parts. We provide a methodology for the design, development and test results of each part of the device, as well as of the entire system. In addition to dosing reagents by means of a low-cost peristaltic pump, we also present carefully controlled dosing of reagents by an open-source syringe pump. The upgrading of the basic open-source syringe pump is given in terms of pump control and application of a larger syringe. In addition to the basic functions of pH stat, i.e. pH value measurement and maintenance, an improvement allowing the device to be used for potentiometric titration has been made as well. We have demonstrated the device's utility when applied for cellulose fibers oxidation with 2,2,6,6-tetramethylpiperidine-1-oxyl radical, i.e. for TEMPO-mediated oxidation. In support of this, we present the results obtained for the oxidation kinetics, the consumption of added reagent and experimental repeatability. Considering that the open-source scientific tools are available to everyone, and that researchers can construct and adjust the device according to their needs, as well as, that the total cost of the open-source pH stat device, excluding the existing laboratory equipment (pH meter, computer and glossary) was less than 150 EUR, we believe that, at a small fraction of the cost of available commercial offers, our open-source pH stat can significantly improve experimental work where the use of pH stat is necessary.

Variation of mechanical properties and oxidation with radiation dose and source in highly crosslinked remelted UHMWPE.

PubMed

Fung, Mitchell; Bowsher, John G; Van Citters, Douglas W

2018-06-01

Ultra-high molecular weight polyethylene (UHMWPE) is the current gold standard for bearing materials used in total joint arthroplasty. High-dose radiation is commonly used to crosslink UHMWPE, thereby improving its wear resistance. A subsequent remelting step eliminates trapped residual free radicals to promote oxidative stability on the shelf, and to prevent material degradation over the long term. Assessment of clinically retrieved, highly crosslinked UHMWPE devices shows signs of unanticipated oxidation occurring in vivo, despite the absence of free radicals prior to implantation. These findings warrant further investigation into possible factors impacting this phenomenon along with its clinical implications. The overall objective of this work is to quantify the influence of irradiation dose and source on UHMWPE's oxidative stability, along with the effects of oxidation on the ultimate mechanical properties, including strength, ductility, and toughness. The results showed a strong positive correlation between maximum oxidation and initial transvinylene content. Critical oxidation levels in the context of mechanical property loss were determined for e-beam and gamma treatments at various radiation doses. Further, it was shown that critical oxidation was more dependent on radiation dose and less dependent on source. If in vivo oxidation persists in these devices, this can potentially lead to mechanical failure (e.g. fatigue damage) as observed in terminally gamma-sterilized devices. Copyright © 2018 Elsevier Ltd. All rights reserved.

Feed network and electromagnetic radiation source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ardavan, Arzhang; Singleton, John; Linehan, Kevin E.

An antenna may include a volume polarization current radiator and a feed network. The volume polarization current radiator, includes a dielectric solid (such as a dielectric strip), and a plurality of closely-spaced excitation elements (24), each excitation element (24) being configured to induce a volume polarization current distribution in the dielectric solid proximate to the excitation element when a voltage is applied to the excitation element. The feed network is coupled to the volume polarization current radiator. The feed network also includes a plurality of passive power divider elements (32) and a plurality of passive delay elements (d1-d6) coupling themore » first port (30) and the plurality of second ports (108, 109, 164), the plurality of power divider elements (32) and the plurality of phase delay elements (d1-d6) being configured such that a radio-frequency signal that is applied to the first port (30) experiences a progressive change of phase as it is coupled to the plurality of second ports (108, 109, 164) so as to cause the volume polarization current distribution to propagate along the dielectric solid.« less

Radiation Detection Center on the Front Lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hazi, A

2005-09-20

Many of today's radiation detection tools were developed in the 1960s. For years, the Laboratory's expertise in radiation detection resided mostly within its nuclear test program. When nuclear testing was halted in the 1990s, many of Livermore's radiation detection experts were dispersed to other parts of the Laboratory, including the directorates of Chemistry and Materials Science (CMS); Physics and Advanced Technologies (PAT); Defense and Nuclear Technologies (DNT); and Nonproliferation, Arms Control, and International Security (NAI). The RDC was formed to maximize the benefit of radiation detection technologies being developed in 15 to 20 research and development (R&D) programs. These effortsmore » involve more than 200 Laboratory employees across eight directorates, in areas that range from electronics to computer simulations. The RDC's primary focus is the detection, identification, and analysis of nuclear materials and weapons. A newly formed outreach program within the RDC is responsible for conducting radiation detection workshops and seminars across the country and for coordinating university student internships. Simon Labov, director of the RDC, says, ''Virtually all of the Laboratory's programs use radiation detection devices in some way. For example, DNT uses radiation detection to create radiographs for their work in stockpile stewardship and in diagnosing explosives; CMS uses it to develop technology for advancing the detection, diagnosis, and treatment of cancer; and the Energy and Environment Directorate uses radiation detection in the Marshall Islands to monitor the aftermath of nuclear testing in the Pacific. In the future, the National Ignition Facility will use radiation detection to probe laser targets and study shock dynamics.''« less

NGSI student activities in open source information analysis in support of the training program of the U.S. DOE laboratories for the entry into force of the additional protocol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandoval, M Analisa; Uribe, Eva C; Sandoval, Marisa N

2009-01-01

In 2008 a joint team from Los Alamos National Laboratory (LANL) and Brookhaven National Laboratory (BNL) consisting of specialists in training of IAEA inspectors in the use of complementary access activities formulated a training program to prepare the U.S. Doe laboratories for the entry into force of the Additional Protocol. As a major part of the support of the activity, LANL summer interns provided open source information analysis to the LANL-BNL mock inspection team. They were a part of the Next Generation Safeguards Initiative's (NGSI) summer intern program aimed at producing the next generation of safeguards specialists. This paper describesmore » how they used open source information to 'backstop' the LANL-BNL team's effort to construct meaningful Additional Protocol Complementary Access training scenarios for each of the three DOE laboratories, Lawrence Livermore National Laboratory, Idaho National Laboratory, and Oak Ridge National Laboratory.« less

Measuring the activity of a {sup 51}Cr neutrino source based on the gamma-radiation spectrum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gorbachev, V. V., E-mail: vvgor-gfb1@mail.ru; Gavrin, V. N.; Ibragimova, T. V.

A technique for the measurement of activities of intense β sources by measuring the continuous gamma-radiation (internal bremsstrahlung) spectra is developed. A method for reconstructing the spectrum recorded by a germanium semiconductor detector is described. A method for the absolute measurement of the internal bremsstrahlung spectrum of {sup 51}Cr is presented.

Supernova dynamics in the laboratory: Radiative shocks produced by ultra-high pressure implosion experiments on the National Ignition Facility

NASA Astrophysics Data System (ADS)

Pak, Arthur

2012-10-01

Thermonuclear fuel experiments on the National Ignition Facility implode 2-mm diameter capsules with a cryogenic deuterium-tritium ice layer to 1000x liquid density and pressures exceeding 100 Gbar (10^11 atm). About 200 ps after peak compression, a spherical supernova-like radiative shock wave is observed that expands with shock velocities of uS = 300 km/s, temperatures of order 1 keV at densities of 1 g/cc resulting in a radiation strength parameter of Q ˜uS^5 = 10^4. Radiation-hydrodynamic simulations indicate that the shock launched at stagnation first goes down a strong density gradient while propagating outward from the highly compressed DT fuel (˜ 1000g/cc) to the ablation front (˜ 1 g/cc). Similar to what happens inside a star, the shock pressure drops as it accelerates and heats. The radiative shock emission is first observed when it breaks out of the dense compressed fuel shell into the low-density inflowing plasma at the ablation front mimicking the supernova situation where the shock breaks out through the star surface into surrounding in-falling matter [1,2]; the shock is subsequently approaching the supercritical state with a strong pre-cursor followed by rapid cooling. These observations are consistent with the rapid vanishing of the radiation ring 400 ps after peak compression due to strong radiation losses and spherical expansion. The evolution and brightness of the radiative shock provides insight into the performance of these implosions that have the goal to produce burning fusion plasmas in the laboratory. By modifying the capsule ablator composition and thickness, the stagnation pressure, density gradients, shock velocity and radiative properties could be tailored to study various regimes related to supernovae radiative remnants.[4pt] [1] W. David Arnett, Supernovae as phenomena of high-energy astrophysics, Ann NY Aca. Science 302, 90 (1977).[0pt] [2] L. Ensman and A. Burrows, Shock breakout in SN1987A, ApJ 393, 742.

Artificial Optical Radiation photobiological hazards in arc welding.

PubMed

Gourzoulidis, G A; Achtipis, A; Topalis, F V; Kazasidis, M E; Pantelis, D; Markoulis, A; Kappas, C; Bourousis, C A

2016-08-01

Occupational Health and Safety (OHS) is associated with crucial social, economic, cultural and technical issues. A highly specialized OHS sector deals with the photobiological hazards from artificial optical radiation (AOR), which is divided into visible light, UV and IR emitted during various activities and which is legally covered by European Directive 2006/25/EC. Among the enormous amount of sources emitting AOR, the most important non-coherent ones to consider for health effects to the whole optical range, are arcs created during metal welding. This survey presents the effort to assess the complicated exposure limits of the Directive in the controlled environment of a welding laboratory. Sensors covering the UV and blue light range were set to measure typical welding procedures reproduced in the laboratory. Initial results, apart from apparently justifying the use of Personal Protective Equipment (PPE) due to even subsecond overexposures measured, also set the basis to evaluate PPE's properties and support an integrated risk assessment of the complex welding environment. These results can also improve workers' and employer's information and training about radiation hazards, which is a crucial OHS demand. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Utilization of SRNL-developed radiation-resistant polymer in high radiation environments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skibo, A.

The radiation-resistant polymer developed by the Savannah River National Laboratory is adaptable for multiple applications to enhance polymer endurance and effectiveness in radiation environments. SRNL offers to collaborate with TEPCO in evaluation, testing, and utilization of SRNL’s radiation-resistant polymer in the D&D of the Fukushima Daiichi NPS. Refinement of the scope and associated costs will be conducted in consultation with TECPO.

Novel particle and radiation sources and advanced materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mako, Frederick

The influence Norman Rostoker had on the lives of those who had the pleasure of knowing him is profound. The skills and knowledge I gained as a graduate student researching collective ion acceleration has fueled a career that has evolved from particle beam physics to include particle and radiation source development and advanced materials research, among many other exciting projects. The graduate research performed on collective ion acceleration was extended by others to form the backbone for laser driven plasma ion acceleration. Several years after graduate school I formed FM Technologies, Inc., (FMT), and later Electron Technologies, Inc. (ETI). Currently,more » as the founder and president of both FMT and ETI, the Rostoker influence can still be felt. One technology that we developed is a self-bunching RF fed electron gun, called the Micro-Pulse Gun (MPG). The MPG has important applications for RF accelerators and microwave tube technology, specifically clinically improved medical linacs and “green” klystrons. In addition to electron beam and RF source research, knowledge of materials and material interactions gained indirectly in graduate school has blossomed into breakthroughs in materials joining technologies. Most recently, silicon carbide joining technology has been developed that gives robust helium leak tight, high temperature and high strength joints between ceramic-to-ceramic and ceramic-to-metal. This joining technology has the potential to revolutionize the ethylene production, nuclear fuel and solar receiver industries by finally allowing for the practical use of silicon carbide as furnace coils, fuel rods and solar receptors, respectively, which are applications that have been needed for decades.« less