WorldWideScience

Sample records for accelerator-based radiation sources

  1. An accelerator-based epithermal photoneutron source for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, D.W.; Mitchell, H.E.; Harker, Y.D.; Yoon, W.Y. [and others

    1995-11-01

    Therapeutically-useful epithermal-neutron beams for BNCT are currently generated by nuclear reactors. Various accelerator-based neutron sources for BNCT have been proposed and some low intensity prototypes of such sources, generally featuring the use of proton beams and beryllium or lithium targets have been constructed. This paper describes an alternate approach to the realization of a clinically useful accelerator-based source of epithermal neutrons for BNCT that reconciles the often conflicting objectives of target cooling, neutron beam intensity, and neutron beam spectral purity via a two stage photoneutron production process.

  2. Laser wakefield accelerator based light sources: potential applications and requirements

    Energy Technology Data Exchange (ETDEWEB)

    Albert, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). NIF and Photon Sciences; Thomas, A. G. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Nuclear Engineering and Radiological Sciences; Mangles, S. P.D. [Imperial College, London (United Kingdom). Blackett Lab.; Banerjee, S. [Univ. of Nebraska, Lincoln, NE (United States); Corde, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Flacco, A. [ENSTA, CNRS, Ecole Polytechnique, Palaiseau (France); Litos, M. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Neely, D. [Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Rutherford Appleton Lab. (RAL). Central Laser Facility; Viera, J. [Univ. of Lisbon (Portugal). GoLP-Inst. de Plasmas e Fusao Nuclear-Lab. Associado; Najmudin, Z. [Imperial College, London (United Kingdom). Blackett Lab.; Bingham, R. [Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Rutherford Appleton Lab. (RAL). Central Laser Facility; Joshi, C. [Univ. of California, Los Angeles, CA (United States). Dept. of Electrical Engineering; Katsouleas, T. [Duke Univ., Durham, NC (United States). Platt School of Engineering

    2015-01-15

    In this article we review the prospects of laser wakefield accelerators as next generation light sources for applications. This work arose as a result of discussions held at the 2013 Laser Plasma Accelerators Workshop. X-ray phase contrast imaging, X-ray absorption spectroscopy, and nuclear resonance fluorescence are highlighted as potential applications for laser-plasma based light sources. We discuss ongoing and future efforts to improve the properties of radiation from plasma betatron emission and Compton scattering using laser wakefield accelerators for these specific applications.

  3. Applications of laser wakefield accelerator-based light sources

    Science.gov (United States)

    Albert, Félicie; Thomas, Alec G. R.

    2016-11-01

    Laser-wakefield accelerators (LWFAs) were proposed more than three decades ago, and while they promise to deliver compact, high energy particle accelerators, they will also provide the scientific community with novel light sources. In a LWFA, where an intense laser pulse focused onto a plasma forms an electromagnetic wave in its wake, electrons can be trapped and are now routinely accelerated to GeV energies. From terahertz radiation to gamma-rays, this article reviews light sources from relativistic electrons produced by LWFAs, and discusses their potential applications. Betatron motion, Compton scattering and undulators respectively produce x-rays or gamma-rays by oscillating relativistic electrons in the wakefield behind the laser pulse, a counter-propagating laser field, or a magnetic undulator. Other LWFA-based light sources include bremsstrahlung and terahertz radiation. We first evaluate the performance of each of these light sources, and compare them with more conventional approaches, including radio frequency accelerators or other laser-driven sources. We have then identified applications, which we discuss in details, in a broad range of fields: medical and biological applications, military, defense and industrial applications, and condensed matter and high energy density science.

  4. Strengthening the inherent safety and security of radioactive sources: Accelerator based options

    International Nuclear Information System (INIS)

    First and foremost, radioactive sources are both useful and cost effective. If a technology can't be utilized in an effective manner, it won't be useful, no matter how clever and elegant it is. Secondly, there are safety and proliferation concerns that must be addressed. Accidents, contamination, dirty bombs, etc., all represent real concerns. A single incident can impact the cost of all uses. These issues and regulations devised to reduce these risks are driving up the costs and lowering efficiency. An alternative would be the accelerator based option, which is nothing new, it has been around for decades. Using accelerator technologies to produce radiation will address the issues I raise by limiting the production of radiation to only those times when a switch has been flipped. Producing radiation that way has one main advantage over the use of radioactive sources. When the switch is off, there is no radiation. Making instruments that are doubly fail-safe is straightforward. Issues associated with radiation safety during transport and storage disappear. There are also minimal issues of disposal and tracking of materials. There is very little potential for diverting a transportable radiography machine or portable neutron generator for nefarious uses. There is a need to carefully monitor the balance between the increasing number of radioactive sources in use, increasing concern for their location and condition, and the cost of employing radiation generators. In many cases there will be a natural progression away from using sources towards the use of radiation generators. Another key factor that would influence this balance is if an accident and or misuse of radioactive sources were to occur. The costs of dealing with sources would rapidly escalate, and would likely tip the balance sooner

  5. Additive effect of BPA and Gd-DTPA for application in accelerator-based neutron source.

    Science.gov (United States)

    Yoshida, F; Yamamoto, T; Nakai, K; Zaboronok, A; Matsumura, A

    2015-12-01

    Because of its fast metabolism gadolinium as a commercial drug was not considered to be suitable for neutron capture therapy. We studied additive effect of gadolinium and boron co-administration using colony forming assay. As a result, the survival of tumor cells with additional 5 ppm of Gd-DTPA decreased to 1/10 compared to the cells with boron only. Using gadolinium to increase the effect of BNCT instead of additional X-ray irradiation might be beneficial, as such combination complies with the short-time irradiation regimen at the accelerator-based neutron source. PMID:26242560

  6. Characterisation of an accelerator-based neutron source for BNCT versus beam energy

    CERN Document Server

    Agosteo, S; D'Errico, F; Nath, R; Tinti, R

    2002-01-01

    Neutron capture in sup 1 sup 0 B produces energetic alpha particles that have a high linear energy transfer in tissue. This results in higher cell killing and a higher relative biological effectiveness compared to photons. Using suitably designed boron compounds which preferentially localize in cancerous cells instead of healthy tissues, boron neutron capture therapy (BNCT) has the potential of providing a higher tumor cure rate within minimal toxicity to normal tissues. This clinical approach requires a thermal neutron source, generally a nuclear reactor, with a fluence rate sufficient to deliver tumorcidal doses within a reasonable treatment time (minutes). Thermal neutrons do not penetrate deeply in tissue, therefore BNCT is limited to lesions which are either superficial or otherwise accessible. In this work, we investigate the feasibility of an accelerator-based thermal neutron source for the BNCT of skin melanomas. The source was designed via MCNP Monte Carlo simulations of the thermalization of a fast ...

  7. Characterisation of an accelerator-based neutron source for BNCT of explanted livers

    Energy Technology Data Exchange (ETDEWEB)

    Agosteo, S. [Politecnico di Milano (Italy). Dipartimento di Ingeneria Nucleare; Colautti, P. [INFN, Padova (Italy). Laboratori Nazionali di Legnaro; Corrado, M.G. [Universita degli Studi di Milano (Italy). Dipartimento di Fisica; d`Errico, F. [Pisa Univ. (Italy). Dipt. di Costruzioni Meccaniche e Nucleari; Matzke, M. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Monti, S.; Tinti, R. [ENEA-ERG-FIRE, Bologna (Italy); Silari, M. [Consiglio Nazionale delle Ricerche, Milan (Italy)

    1997-09-01

    An accelerator-based thermal neutron source for BNCT of the explanted liver was designed using the MCNP code. Neutrons are generated via (d,n) reactions by 7 MeV deuterons bombarding a beryllium target. The therapy constraints were approached by simulating an irradiation cavity placed inside a graphite reflector parallelepiped containing a heavy-water moderator in turn enclosing the beryllium target. The experimental verification was performed at the Laboratori Nazionali di Legnaro (Italy). The thermal and epithermal neutron flux was measured at various positions in the irradiation cavity by means of activation techniques employing bare and cadmium covered indium foils. Further measurements were performed with BF{sub 3} detectors. The fast neutron component of the dose equivalent and the energy spectrum above 100keV were assessed by means of a recently developed technique employing variable threshold superheated drop detectors. The prompt gamma ray dose was measured with {sup 7}LiF TLDs. (author).

  8. An accelerator-based epithermal photoneutron source for boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, H.E.

    1996-04-01

    Boron neutron capture therapy is an experimental binary cancer radiotherapy modality in which a boronated pharmaceutical that preferentially accumulates in malignant tissue is first administered, followed by exposing the tissue in the treatment volume to a thermal neutron field. Current usable beams are reactor-based but a viable alternative is the production of an epithermal neutron beam from an accelerator. Current literature cites various proposed accelerator-based designs, most of which are based on proton beams with beryllium or lithium targets. This dissertation examines the efficacy of a novel approach to BNCT treatments that incorporates an electron linear accelerator in the production of a photoneutron source. This source may help to resolve some of the present concerns associated with accelerator sources, including that of target cooling. The photoneutron production process is discussed as a possible alternate source of neutrons for eventual BNCT treatments for cancer. A conceptual design to produce epithermal photoneutrons by high photons (due to bremsstrahlung) impinging on deuterium targets is presented along with computational and experimental neutron production data. A clinically acceptable filtered epithermal neutron flux on the order of 10{sup 7} neutrons per second per milliampere of electron current is shown to be obtainable. Additionally, the neutron beam is modified and characterized for BNCT applications by employing two unique moderating materials (an Al/AlF{sub 3} composite and a stacked Al/Teflon design) at various incident electron energies.

  9. An accelerator-based epithermal photoneutron source for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Boron neutron capture therapy is an experimental binary cancer radiotherapy modality in which a boronated pharmaceutical that preferentially accumulates in malignant tissue is first administered, followed by exposing the tissue in the treatment volume to a thermal neutron field. Current usable beams are reactor-based but a viable alternative is the production of an epithermal neutron beam from an accelerator. Current literature cites various proposed accelerator-based designs, most of which are based on proton beams with beryllium or lithium targets. This dissertation examines the efficacy of a novel approach to BNCT treatments that incorporates an electron linear accelerator in the production of a photoneutron source. This source may help to resolve some of the present concerns associated with accelerator sources, including that of target cooling. The photoneutron production process is discussed as a possible alternate source of neutrons for eventual BNCT treatments for cancer. A conceptual design to produce epithermal photoneutrons by high photons (due to bremsstrahlung) impinging on deuterium targets is presented along with computational and experimental neutron production data. A clinically acceptable filtered epithermal neutron flux on the order of 107 neutrons per second per milliampere of electron current is shown to be obtainable. Additionally, the neutron beam is modified and characterized for BNCT applications by employing two unique moderating materials (an Al/AlF3 composite and a stacked Al/Teflon design) at various incident electron energies

  10. Industrial applications of accelerator-based infrared sources: Analysis using infrared microspectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bantignies, J.L.; Fuchs, G.; Wilhelm, C. [Elf Atochem, Pierre-Benite (France); Carr, G.L. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source; Dumas, P. [Centre Univ. Paris-Sud, Orsay (France)

    1997-09-01

    Infrared Microspectroscopy, using a globar source, is now widely employed in the industrial environment, for the analysis of various materials. Since synchrotron radiation is a much brighter source, an enhancement of an order of magnitude in lateral resolution can be achieved. Thus, the combination of IR microspectroscopy and synchrotron radiation provides a powerful tool enabling sample regions only few microns size to be studied. This opens up the potential for analyzing small particles. Some examples for hair, bitumen and polymer are presented.

  11. Prospect for application of compact accelerator-based neutron source to neutron engineering diffraction

    Science.gov (United States)

    Ikeda, Yoshimasa; Taketani, Atsushi; Takamura, Masato; Sunaga, Hideyuki; Kumagai, Masayoshi; Oba, Yojiro; Otake, Yoshie; Suzuki, Hiroshi

    2016-10-01

    A compact accelerator-based neutron source has been lately discussed on engineering applications such as transmission imaging and small angle scattering as well as reflectometry. However, nobody considers using it for neutron diffraction experiment because of its low neutron flux. In this study, therefore, the neutron diffraction experiments are carried out using Riken Accelerator-driven Compact Neutron Source (RANS), to clarify the capability of the compact neutron source for neutron engineering diffraction. The diffraction pattern from a ferritic steel was successfully measured by suitable arrangement of the optical system to reduce the background noise, and it was confirmed that the recognizable diffraction pattern can be measured by a large sampling volume with 10 mm in cubic for an acceptable measurement time, i.e. 10 min. The minimum resolution of the 110 reflection for RANS is approximately 2.5% at 8 μs of the proton pulse width, which is insufficient to perform the strain measurement by neutron diffraction. The moderation time width at the wavelength corresponding to the 110 reflection is estimated to be approximately 30 μs, which is the most dominant factor to determine the resolution. Therefore, refinements of the moderator system to decrease the moderation time by decreasing a thickness of the moderator or by applying the decoupler system or application of the angular dispersive neutron diffraction technique are important to improve the resolution of the diffraction experiment using the compact neutron source. In contrast, the texture evolution due to plastic deformation was successfully observed by measuring a change in the diffraction peak intensity by RANS. Furthermore, the volume fraction of the austenitic phase in the dual phase mock specimen was also successfully evaluated by fitting the diffraction pattern using a Rietveld code. Consequently, RANS has been proved to be capable for neutron engineering diffraction aiming for the easy access

  12. Study of medical RI production with accelerator-based neutron sources

    International Nuclear Information System (INIS)

    The single-photon emission computed tomography (SPECT) and positron emission tomography (PET) have been widely adopted for nuclear medicine imaging to make diagnoses of body functions, identification of site of cancers, and so on. Now, almost all of medical radio isotopes are produced by nuclear reactors or charged particle accelerators. We propose a new route to produce the medical radio isotopes with accelerator-based neutron sources. In this paper, as an example, we introduce the proposed production method of 99Mo, which is the mother nuclide of 99mTc for SPECT. We determined the 100Mo(n,2n)99Mo reaction cross section to 1,415±82mb and it was consistent with the value (1,398mb) obtained from JENDL-4.0. Therefore, it indicates yields of produced RIs can be predicted with nuclear data based simulations. The simulation also can be used to design irradiation condition. In this paper some results of the simulations are also shown. (author)

  13. Characterisation of an accelerator-based neutron source for BNCT versus beam energy

    Energy Technology Data Exchange (ETDEWEB)

    Agosteo, S. E-mail: stefano.agosteo@polimi.it; Curzio, G.; D' Errico, F.; Nath, R.; Tinti, R

    2002-01-01

    Neutron capture in {sup 10}B produces energetic alpha particles that have a high linear energy transfer in tissue. This results in higher cell killing and a higher relative biological effectiveness compared to photons. Using suitably designed boron compounds which preferentially localize in cancerous cells instead of healthy tissues, boron neutron capture therapy (BNCT) has the potential of providing a higher tumor cure rate within minimal toxicity to normal tissues. This clinical approach requires a thermal neutron source, generally a nuclear reactor, with a fluence rate sufficient to deliver tumorcidal doses within a reasonable treatment time (minutes). Thermal neutrons do not penetrate deeply in tissue, therefore BNCT is limited to lesions which are either superficial or otherwise accessible. In this work, we investigate the feasibility of an accelerator-based thermal neutron source for the BNCT of skin melanomas. The source was designed via MCNP Monte Carlo simulations of the thermalization of a fast neutron beam, generated by 7 MeV deuterons impinging on a thick target of beryllium. The neutron field was characterized at several deuteron energies (3.0-6.5 MeV) in an experimental structure installed at the Van De Graaff accelerator of the Laboratori Nazionali di Legnaro, in Italy. Thermal and epithermal neutron fluences were measured with activation techniques and fast neutron spectra were determined with superheated drop detectors (SDD). These neutron spectrometry and dosimetry studies indicated that the fast neutron dose is unacceptably high in the current design. Modifications to the current design to overcome this problem are presented.

  14. PREFACE: 6th Workshop on Infrared Spectroscopy and Microscopy with Accelerator-Based Sources (WIRMS11)

    Science.gov (United States)

    Lupi, Stefano; Perucchi, Andrea

    2012-05-01

    This volume of Journal of Physics: Conference Series is dedicated to a subset of papers related to the work presented at the 6th edition of the international Workshop on Infrared Spectroscopy and Microscopy with Accelerator-Based Sources (WIRMS), held in Trieste, Italy, September 4-8 2011. Previous editions of the conference were held in Porquerolles (France), Lake Tahoe (USA), Rathen (Germany), Awaji (Japan), and Banff (Canada). This edition was organized and chaired by Stefano Lupi (Roma La Sapienza) and co-chaired by Andrea Perucchi (Elettra), with the support of the Italian Synchrotron Light Laboratory ELETTRA, which was honored to host the WIRMS workshop in its tenth anniversary. The 6th WIRMS edition addressed several different topics, ranging from biochemistry to strongly correlated materials, from geology to conservation science, and from forensics to the study of cometary dusts. Representatives from the infrared scientific programs at synchrotron light sources and free-electron-laser facilities. This edition was attended by 88 participants, including representatives from the infrared scientific programs at synchrotron light sources and free-electron-laser facilities, who enjoyed the stimulating scientific presentations, several detailed discussions, and the beautiful weather and scenery of the Trieste gulf. Participants came from 16 different nations and four continents, including many young scientists, six of which were supported by the organizers. There were 45 scientific talks divided in 11 sessions: Facilities, Microspectroscopy (I, II, III), Time-Resolved Spectroscopies, Extreme Conditions, Condensed Matter, Near-Field, Imaging, THz Techniques and High-Resolution Spectroscopy. 37 posters were also presented at two very lively evening poster sessions. We would like to use the opportunity of writing this preface to thank all the participants of the workshop for the very high level of their scientific contribution and for the very friendly atmosphere

  15. Factors Predictive of Symptomatic Radiation Injury After Linear Accelerator-Based Stereotactic Radiosurgery for Intracerebral Arteriovenous Malformations

    Energy Technology Data Exchange (ETDEWEB)

    Herbert, Christopher, E-mail: cherbert@bccancer.bc.ca [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, BC (Canada); Moiseenko, Vitali [Department of Medical Physics, British Columbia Cancer Agency, Vancouver, BC (Canada); McKenzie, Michael [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, BC (Canada); Redekop, Gary [Division of Neurosurgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Canada); Hsu, Fred [Department of Radiation Oncology, British Columbia Cancer Agency, Abbotsford, BC (Canada); Gete, Ermias; Gill, Brad; Lee, Richard; Luchka, Kurt [Department of Medical Physics, British Columbia Cancer Agency, Vancouver, BC (Canada); Haw, Charles [Division of Neurosurgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Canada); Lee, Andrew [Department of Neurosurgery, Royal Columbian Hospital, New Westminster, BC (Canada); Toyota, Brian [Division of Neurosurgery, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Canada); Martin, Montgomery [Department of Medical Imaging, British Columbia Cancer Agency, Vancouver, BC (Canada)

    2012-07-01

    Purpose: To investigate predictive factors in the development of symptomatic radiation injury after treatment with linear accelerator-based stereotactic radiosurgery for intracerebral arteriovenous malformations and relate the findings to the conclusions drawn by Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC). Methods and Materials: Archived plans for 73 patients who were treated at the British Columbia Cancer Agency were studied. Actuarial estimates of freedom from radiation injury were calculated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards models were used for analysis of incidence of radiation injury. Log-rank test was used to search for dosimetric parameters associated with freedom from radiation injury. Results: Symptomatic radiation injury was exhibited by 14 of 73 patients (19.2%). Actuarial rate of symptomatic radiation injury was 23.0% at 4 years. Most patients (78.5%) had mild to moderate deficits according to Common Terminology Criteria for Adverse Events, version 4.0. On univariate analysis, lesion volume and diameter, dose to isocenter, and a V{sub x} for doses {>=}8 Gy showed statistical significance. Only lesion diameter showed statistical significance (p < 0.05) in a multivariate model. According to the log-rank test, AVM volumes >5 cm{sup 3} and diameters >30 mm were significantly associated with the risk of radiation injury (p < 0.01). The V{sub 12} also showed strong association with the incidence of radiation injury. Actuarial incidence of radiation injury was 16.8% if V{sub 12} was <28 cm{sup 3} and 53.2% if >28 cm{sup 3} (log-rank test, p = 0.001). Conclusions: This study confirms that the risk of developing symptomatic radiation injury after radiosurgery is related to lesion diameter and volume and irradiated volume. Results suggest a higher tolerance than proposed by QUANTEC. The widely differing findings reported in the literature, however, raise considerable uncertainties.

  16. An accelerator-based neutron microbeam system for studies of radiation effects

    OpenAIRE

    Xu, Yanping; Randers-Pehrson, Gerhard; Marino, Stephen A.; Bigelow, Alan W.; Akselrod, Mark S.; Sykora, Jeff G.; Brenner, David J.

    2010-01-01

    A novel neutron microbeam is being developed at the Radiological Research Accelerator Facility (RARAF) of Columbia University. The RARAF microbeam facility has been used for studies of radiation bystander effects in mammalian cells for many years. Now a prototype neutron microbeam is being developed that can be used for bystander effect studies. The neutron microbeam design here is based on the existing charged particle microbeam technology at the RARAF. The principle of the neutron microbeam...

  17. Complications following linear accelerator based stereotactic radiation for cerebral arteriovenous malformations

    DEFF Research Database (Denmark)

    Skjøth-Rasmussen, Jane; Roed, Henrik; Ohlhues, Lars;

    2010-01-01

    Primarily, gamma knife centers are predominant in publishing results on arteriovenous malformations (AVM) treatments including reports on risk profile. However, many patients are treated using a linear accelerator-most of these at smaller centers. Because this setting is different from a large...... gamma knife center, the risk profile at Linac departments could be different from the reported experience. Prescribed radiation doses are dependent on AVM volume. This study details results from a medium sized Linac department center focusing on risk profiles....

  18. Accelerator based neutron source for the neutron capture therapy at hospital

    International Nuclear Information System (INIS)

    Accelerator source of epithermal neutrons for the hospital-based boron neutron capture therapy is proposed and discussed. Kinematically collimated neutrons are produced via near-threshold 7Li(p, n)7Be reaction at proton energies of 1.883 - 1.9 MeV. Steady-state accelerator current of 40 mA allows to provide therapeutically useful beams with treatment times of tens of minutes. The basic components of the facility are a hydrogen negative ion source, an electrostatic tandem accelerator with vacuum insulation, a sectioned rectifier, and a thin lithium neutron generating target on the surface of tungsten disk cooled by liquid metal heat carrier. Design features of facility components are discussed. The possibility of stabilization of proton energy is considered. At proton energy of 2.5 MeV the neutron beam production for NCT usage after moderation is also considered. (author)

  19. The Argonne ACWL, a potential accelerator-based neutron source for BNCT

    International Nuclear Information System (INIS)

    THE CWDD (Continuous Wave Deuterium Demonstrator) accelerator was designed to accelerate 80 mA cw of D- to 7.5 MeV. Most of the hardware for the first 2 MeV was installed at Argonne and major subsystems had been commissioned when program funding from the Ballistic Missile Defense Organization ended in October 1993. Renamed the Argonne Continuous Wave Linac (ACWL), we are proposing to complete it to accelerate either deuterons to 2 MeV or protons to 3-3.5 MeV. Equipped with a beryllium or other light-element target, it would make a potent source of neutrons (on the order of 1013 n/s) for BNCT and/or neutron radiography. Project status and proposals for turning ACWL into a neutron source are reviewed, including the results of a computational study that was carried out to design a target/moderator to produce an epithermal neutron beam for BNCT. (orig.)

  20. Accelerator-based neutron source for the neutron-capture and fast neutron therapy at hospital

    Science.gov (United States)

    Bayanov, B. F.; Belov, V. P.; Bender, E. D.; Bokhovko, M. V.; Dimov, G. I.; Kononov, V. N.; Kononov, O. E.; Kuksanov, N. K.; Palchikov, V. E.; Pivovarov, V. A.; Salimov, R. A.; Silvestrov, G. I.; Skrinsky, A. N.; Soloviov, N. A.; Taskaev, S. Yu.

    The proton accelerator complex for neutron production in lithium target discussed, which can operate in two modes. The first provides a neutron beam kinematically collimated with good forward direction in 25° and average energy of 30 keV, directly applicable for neutron-capture therapy with high efficiency of proton beam use. The proton energy in this mode is 1.883-1.890 MeV that is near the threshold of the 7Li( p, n) 7Be reaction. In the second mode, at proton energy of 2.5 MeV, the complex-produced neutron beam with maximum energy board of 790 keV which can be used directly for fast neutron therapy and for neutron-capture therapy after moderation. The project of such a neutron source is based on the 2.5 MeV original electrostatic accelerator tandem with vacuum insulation developed at BINP which is supplied with a high-voltage rectifier. The rectifier is produced in BINP as a part of ELV-type industrial accelerator. Design features of the tandem determining its high reliability in operation with a high-current (up to 40 mA) H - ion beam are discussed. They are: the absence of ceramic accelerator columns around the beam passage region, good conditions for pumping out of charge-exchange gaseous target region, strong focusing optics and high acceleration rate minimizing the space charge effects. The possibility of stabilization of protons energy with an accuracy level of 0.1% necessary for operation in the near threshold region is considered. The design description of H - continuous ion source with a current of 40 mA is also performed. To operate with a 100 kW proton beam it is proposed to use liquid-lithium targets. A thin lithium layer on the surface of a tungsten disk cooled intensively by a liquid metal heat carrier is proposed for use in case of the vertical beam, and a flat liquid lithium jet flowing through the narrow nozzle - for the horizontal beam.

  1. New sources of radiation

    Energy Technology Data Exchange (ETDEWEB)

    Schimmerling, W.

    1979-09-01

    An attempt is made to select examples of radiation sources whose application may make new or unconventional demands on radiation protection and dosimetry. A substantial body of knowledge about high energy facilities exists and, partly for this reason, the great high energy accelerators are mentioned only briefly.

  2. New sources of radiation

    International Nuclear Information System (INIS)

    An attempt is made to select examples of radiation sources whose application may make new or unconventional demands on radiation protection and dosimetry. A substantial body of knowledge about high energy facilities exists and, partly for this reason, the great high energy accelerators are mentioned only briefly

  3. India's first synchrotron radiation source Indus-1: a historical perspective

    International Nuclear Information System (INIS)

    The first Indian synchrotron radiation source Indus-l was commissioned in May 1999. This article briefs the development of accelerator based research programme in India and discusses the historical perspectives starting from the year 1953 at and goes to the development of Indus-1 and Indus-2 at Centre for Advanced Technology at Indore

  4. Radiation Source Replacement Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  5. Development of high intensity ion sources for a Tandem-Electrostatic-Quadrupole facility for Accelerator-Based Boron Neutron Capture Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bergueiro, J. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica (Argentina)] [CONICET, Buenos Aires (Argentina); Igarzabal, M.; Suarez Sandin, J.C. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica (Argentina); Somacal, H.R. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina); Thatar Vento, V. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica (Argentina)] [CONICET, Buenos Aires (Argentina); Huck, H.; Valda, A.A. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina); Repetto, M. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica (Argentina)

    2011-12-15

    Several ion sources have been developed and an ion source test stand has been mounted for the first stage of a Tandem-Electrostatic-Quadrupole facility For Accelerator-Based Boron Neutron Capture Therapy. A first source, designed, fabricated and tested is a dual chamber, filament driven and magnetically compressed volume plasma proton ion source. A 4 mA beam has been accelerated and transported into the suppressed Faraday cup. Extensive simulations of the sources have been performed using both 2D and 3D self-consistent codes.

  6. Final report of the IAEA advisory group meeting on accelerator-based nuclear analytical techniques for characterization and source identification of aerosol particles

    International Nuclear Information System (INIS)

    The field of aerosol characterization and source identification covers a wide range of scientific and technical activities in many institutions, in both developed and developing countries. This field includes research and applications on urban air pollution, source apportionment of suspended particulate matter, radioactive aerosol particles, organic compounds carried on particulate matter, elemental characterization of particles, and other areas. The subject of this AGM focused on the use of accelerator-based nuclear analytical techniques for determination of elemental composition of particles (by either bulk or single particle analysis) and the use of accumulated knowledge for source identification

  7. Doses from Medical Radiation Sources

    Science.gov (United States)

    ... Radiation Protection and Measurements; NCRP Report 124; 1996. United Nations Scientific Committee on the Effects of Atomic Radiation. ... ionizing radiation, Vol. 1: Sources. New York, NY: United Nations Publishing; 2000. Russell JR, Stabin MG, Sparks RB, ...

  8. Future Synchrotron Radiation Sources

    CERN Document Server

    Winick, Herman

    2003-01-01

    Sources of synchrotron radiation (also called synchrotron light) and their associated research facilities have experienced a spectacular growth in number, performance, and breadth of application in the past two to three decades. In 1978 there were eleven electron storage rings used as light sources. Three of these were small rings, all below 500 mega-electron volts (MeV), dedicated to this purpose; the others, with energy up to 5 giga-electron volts (GeV), were used parasitically during the operation of the ring for high energy physics research. In addition, at that time synchrotron radiation from nine cyclic electron synchrotrons, with energy up to 5 GeV, was also used parasitically. At present no cyclic synchrotrons are used, while about 50 electron storage rings are in operation around the world as fully dedicated light sources for basic and applied research in a wide variety of fields. Among these fields are structural molecular biology, molecular environmental science, materials, analytic chemistry, micr...

  9. Synchrotron radiation source Indus-1

    International Nuclear Information System (INIS)

    Indus-1 is a 450 MeV electron storage ring for the production of the synchrotron radiation in VUV range with a critical wavelength of 61 A. In this paper we discuss the synchrotron radiation source Indus-1 and report some results of its present performance. Besides, results of beam lifetime studies are also reported. (author)

  10. Compton Sources of Electromagnetic Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Geoffrey Krafft,Gerd Priebe

    2011-01-01

    When a relativistic electron beam interacts with a high-field laser beam, intense and highly collimated electromagnetic radiation will be generated through Compton scattering. Through relativistic upshifting and the relativistic Doppler effect, highly energetic polarized photons are radiated along the electron beam motion when the electrons interact with the laser light. For example, X-ray radiation can be obtained when optical lasers are scattered from electrons of tens-of-MeV beam energy. Because of the desirable properties of the radiation produced, many groups around the world have been designing, building, and utilizing Compton sources for a wide variety of purposes. In this review article, we discuss the generation and properties of the scattered radiation, the types of Compton source devices that have been constructed to date, and the prospects of radiation sources of this general type. Due to the possibilities of producing hard electromagnetic radiation in a device that is small compared to the alternative storage ring sources, it is foreseen that large numbers of such sources may be constructed in the future.

  11. Searching for Orphan radiation sources

    International Nuclear Information System (INIS)

    Full text: The problem of orphan sources cannot be left unaddressed due high probability of accidental exposure and use of sources for terrorism. Search of objects of this kind is complex particularly when search territory is large. This requires devices capable of detecting sources, identifying their radionuclide composition, and correlating scan results to geographical coordinates and displaying results on a map. Spectral radiation scanner AT6101C can fulfill the objective of search for gamma and neutron radiation sources, radionuclide composition identification, correlation results to geographical coordinates and displaying results on a map. The scanner consists of gamma radiation scintillation detection unit based on NaI(Tl) crystal, neutron detection unit based on two He3 counters, GPS receiver and portable ruggedized computer. Built-in and application software automates entire scan process, saving all results to memory for further analysis with visual representation of results as spectral information diagrams, count rate profile and gamma radiation dose rates on a geographical map. The scanner informs operator with voice messages on detection of radiation sources, identification result and other events. Scanner detection units and accessories are packed in a backpack. Weighing 7 kg, the scanner is human portable and can be used for scan inside cars. The scanner can also be used for radiation mapping and inspections. (author)

  12. Radiation studies in the antiproton source

    International Nuclear Information System (INIS)

    Experiment E760 has a lead glass (Pb-G) calorimeter situated in the antiproton source tunnel in the accumulator ring at location A50. This location is exposed to radiation from several sources during antiproton stacking operations. A series of radiation studies has been performed over the last two years to determine the sources of this radiation and as a result, some shielding has been installed in the antiproton source in order to protect the lead glass from radiation damage

  13. Regulated control of practices and radiation sources

    International Nuclear Information System (INIS)

    Excepting the radiation caused by the natural background radiation, the Executive Secretariat for Nuclear Affairs (SEAN) does not authorize any source no practice within the national territory that may imply exposure of a person to ionizing radiation unless this use is ruled. This document establishes the basic criteria to set up such system as well as to exclude or exempt practices and sources from this regulated control

  14. Treatment Planning for Accelerator-Based Boron Neutron Capture Therapy

    Science.gov (United States)

    Herrera, María S.; González, Sara J.; Minsky, Daniel M.; Kreiner, Andrés J.

    2010-08-01

    Glioblastoma multiforme and metastatic melanoma are frequent brain tumors in adults and presently still incurable diseases. Boron Neutron Capture Therapy (BNCT) is a promising alternative for this kind of pathologies. Accelerators have been proposed for BNCT as a way to circumvent the problem of siting reactors in hospitals and for their relative simplicity and lower cost among other advantages. Considerable effort is going into the development of accelerator-based BNCT neutron sources in Argentina. Epithermal neutron beams will be produced through appropriate proton-induced nuclear reactions and optimized beam shaping assemblies. Using these sources, computational dose distributions were evaluated in a real patient with diagnosed glioblastoma treated with BNCT. The simulated irradiation was delivered in order to optimize dose to the tumors within the normal tissue constraints. Using Monte Carlo radiation transport calculations, dose distributions were generated for brain, skin and tumor. Also, the dosimetry was studied by computing cumulative dose-volume histograms for volumes of interest. The results suggest acceptable skin average dose and a significant dose delivered to tumor with low average whole brain dose for irradiation times less than 60 minutes, indicating a good performance of an accelerator-based BNCT treatment.

  15. Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture

    Energy Technology Data Exchange (ETDEWEB)

    Scott Wilde, Raymond Keegan

    2008-07-01

    The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

  16. Radiation safety and inventory of sealed radiation sources in Pakistan

    International Nuclear Information System (INIS)

    Sealed radiation sources (SRS) of various types and activities are widely used in industry, medicine, agriculture, research and teaching in Pakistan. The proper maintenance of records of SRS is mandatory for users/licensees. Since 1956, more than 2000 radiation sources of different isotopes having activities of Bq to TBq have been imported. Of these, several hundred sources have been disposed of and some have been exported/returned to the suppliers. To ensure the safety and security of the sources and to control and regulate the safe use of radiation sources in various disciplines, the Directorate of Nuclear Safety and Radiation Protection (DNSRP), the implementing arm of the regulatory authority in the country, has introduced a system for notifying, registering and licensing the use of all types of SRS. In order to update the inventory of SRS used throughout the country, the DNSRP has developed a database. (author)

  17. Radiation protection and the safety of radiation sources

    International Nuclear Information System (INIS)

    These Safety Fundamentals cover the protection of human beings against ionizing radiation (gamma and X rays and alpha, beta and other particles that can induce ionization as they interact with biological materials), referred to herein subsequently as radiation, and the safety of sources that produce ionizing radiation. The Fundamentals do not apply to non-ionizing radiation such as microwave, ultraviolet, visible and infrared radiation. They do not apply either to the control of non-radiological aspects of health and safety. They are, however, part of the overall framework of health and safety

  18. All-fiber femtosecond Cherenkov radiation source.

    Science.gov (United States)

    Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe; Tu, Haohua; Boppart, Stephen A; Turchinovich, Dmitry

    2012-07-01

    An all-fiber femtosecond source of spectrally isolated Cherenkov radiation is reported, to the best of our knowledge, for the first time. Using a monolithic, self-starting femtosecond Yb-doped fiber laser as the pump source and the combination of photonic crystal fibers as the wave-conversion medium, we demonstrate milliwatt-level, stable, and tunable Cherenkov radiation at visible wavelengths 580-630 nm, with pulse duration of sub-160-fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such an all-fiber Cherenkov radiation source is promising for practical applications in biophotonics such as bioimaging and microscopy. PMID:22743523

  19. All-fiber femtosecond Cherenkov radiation source

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe;

    2012-01-01

    -conversion medium, we demonstrate milliwatt-level, stable, and tunable Cherenkov radiation at visible wavelengths 580–630 nm, with pulse duration of sub-160-fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such an all-fiber Cherenkov radiation source is promising for practical applications in biophotonics...

  20. Devices for obtaining information about radiation sources

    International Nuclear Information System (INIS)

    The invention provides a sensitive, fast high-resolution device for obtaining information about the distribution of gamma and X-radiation sources and provides a radiation detector useful in such a device. It comprises a slit collimator with a multiplicity of slits each with slit-defining walls of material and thickness to absorb beam components impinging on them. The slits extend further in one direction than the other. The detector for separately detecting beam components passing through the slits also provides data output signals. It comprises a plurality of radiation transducing portions which are not photoconductor elements each at the end of a slit. A positioner operates to change the transverse position of the slits and radiation transducing portions relative to the source, wherein each radiation transducing element is positioned within its respective slit between the slit defining walls. Full details and preferred embodiments are given. (U.K.)

  1. The safe use of radiation sources

    International Nuclear Information System (INIS)

    As a means of promoting safety in the use of radiation sources, as well as encouraging consistency in regulatory control, the IAEA has from time to time organized training courses with the co-operation of Member State governments and organizations, to inform individuals from developing countries with appropriate responsibilities on the provisions for the safe use and regulation of radiation sources. Three such courses on the safe use of radiation sources have been held in both the USA, with the co-operation of the United States Government, and in Dublin, Ireland, with the co-operation of the Irish Government. The Training Course on the Safe Use and Regulation of Radiation Sources has been successfully given to over 77 participants from over 30 countries during the last years. The course is aimed at providing a basis of radiation protection knowledge in all aspects of the uses of radiation and of radiation sources that are used today. It is the intention of this course to provide a systematic enhancement of radioisotope safety in countries with developing radiological programmes through a core group of national authorities. The IAEA's training programmes provide an excellent opportunity for direct contact with lecturers that have extensive experience in resolving issues faced by developing countries and in providing guidance documents useful in addressing their problems. This document uses this collective experience and provides valuable technical information regarding the safety aspects of the uses not only of sealed and unsealed sources of radiation, but also for those machines that produce ionizing radiation. The first of these training courses, 'Safety and Regulation of Unsealed Sources' was held in Dublin, Ireland, June through July 1989 with the co-operation of the Nuclear Energy Board and Trinity College. This was an interregional training course, the participants came from all over the world. The second and third interregional courses, 'Safety and Regulation

  2. Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S.; Goffeney, N.; Henestroza, E. [Lawrence Berkeley Lab., CA (United States)] [and others

    1995-02-22

    A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported.

  3. Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider

    International Nuclear Information System (INIS)

    A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported

  4. Devices for obtaining information about radiation sources

    International Nuclear Information System (INIS)

    The invention provides a sensitive, fast, high-resolution device for obtaining information about the distribution of gamma and X-radiation sources and provides a radiation detector useful in such a device. It comprises a slit collimator with a multiplicity of slits each with slit-defining walls of material and thickness to absorb beam components impinging on them. The slits extend further in one transverse direction than the other. The detector for separately detecting beam components passing through the slits also provides data output signals. It comprises a plurality of radiation transducing portions, each at the end of a slit. A positioner changes the transverse position of the slits and radiation transducer (a photoconductor) relative to the source. Applications are in nuclear medicine and industry. Full details and preferred embodiments are given. (U.K.)

  5. Characterization of coherent Cherenkov radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A.V.

    2015-01-21

    Engineering formulae for calculation of peak, and spectral brightness of resonant long-range wakefield extractor are given. It is shown that the brightness is dominated by beam density in the slow wave structure and antenna gain of the outcoupling. Far field radiation patterns and brightness of circular and high aspect ratio planar radiators are compared. A possibility to approach diffraction limited brightness is demonstrated. The role of group velocity in designing of the Cherenkov source is analyzed. The approach can be applied for design and characterization of various structure-dominated sources (e.g., wakefield extractors with gratings or dielectrics, or FEL-Cherenkov combined sources) radiating into a free space using an antenna (in microwave to sub-mm wave regions). The high group velocity structures can be also effective as energy dechirpers and for diagnostics of microbunched relativistic electron beams.

  6. Maximum Likelihood Localization of Radiation Sources with unknown Source Intensity

    CERN Document Server

    Baidoo-Williams, Henry E

    2016-01-01

    In this paper, we consider a novel and robust maximum likelihood approach to localizing radiation sources with unknown statistics of the source signal strength. The result utilizes the smallest number of sensors required theoretically to localize the source. It is shown, that should the source lie in the open convex hull of the sensors, precisely $N+1$ are required in $\\mathbb{R}^N, ~N \\in \\{1,\\cdots,3\\}$. It is further shown that the region of interest, the open convex hull of the sensors, is entirely devoid of false stationary points. An augmented gradient ascent algorithm with random projections should an estimate escape the convex hull is presented.

  7. Radiation of superluminal sources in vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Bolotovskii, B.M. [P.N. Lebedev Physical Institute, Leninsky prospect 53, Moscow 119991 (Russian Federation)]. E-mail: bolot@lpi.ru; Serov, A.V. [P.N. Lebedev Physical Institute, Leninsky prospect 53, Moscow 119991 (Russian Federation)]. E-mail: serov@x4u.levedev.ru

    2006-08-15

    Vavilov-Cherenkov radiation is emitted by a charged body uniformly moving in a medium when the body velocity exceeds that of light in the medium. Therefore, it was believed that Vavilov-Cherenkov radiation is impossible in vacuum, because the velocity of any material body cannot exceed the light velocity in vacuum. However, it is possible to realize distributions of charges and currents which propagate with any given velocity. Such a superluminal distribution can be used as a source of Vavilov-Cherenkov radiation in vacuum.

  8. All-fiber femtosecond Cherenkov radiation source

    OpenAIRE

    Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe; Tu, Haohua; Boppart, Stephen A.; Turchinovich, Dmitry

    2012-01-01

    An all-fiber femtosecond source of spectrally isolated Cherenkov radiation is reported, to the best of our knowledge, for the first time. Using a monolithic, self-starting femtosecond Yb-doped fiber laser as the pump source and the combination of photonic crystal fibers as the wave-conversion medium, we demonstrate milliwatt-level, stable, and tunable Cherenkov radiation at visible wavelengths 580–630 nm, with pulse duration of sub-160-fs, and the 3 dB spectral bandwidth not exceeding 36 nm. ...

  9. Accelerator-based neutrino oscillation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Deborah A.; /Fermilab

    2007-12-01

    Neutrino oscillations were first discovered by experiments looking at neutrinos coming from extra-terrestrial sources, namely the sun and the atmosphere, but we will be depending on earth-based sources to take many of the next steps in this field. This article describes what has been learned so far from accelerator-based neutrino oscillation experiments, and then describe very generally what the next accelerator-based steps are. In section 2 the article discusses how one uses an accelerator to make a neutrino beam, in particular, one made from decays in flight of charged pions. There are several different neutrino detection methods currently in use, or under development. In section 3 these are presented, with a description of the general concept, an example of such a detector, and then a brief discussion of the outstanding issues associated with this detection technique. Finally, section 4 describes how the measurements of oscillation probabilities are made. This includes a description of the near detector technique and how it can be used to make the most precise measurements of neutrino oscillations.

  10. Sustainably Sourced, Thermally Resistant, Radiation Hard Biopolymer

    Science.gov (United States)

    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

  11. Underdense radiation sources: Moving towards longer wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Back, C.A.; Kilkenny, J.D. [General Atomics, San Diego, California (United States); Seely, J.F.; Weaver, J.L. [Naval Research Laboratory, Washington, DC (United States); Feldman, U. [Artep Inc., Ellicott City, MD (United States); Tommasini, R.; Glendinning, S.G.; Chung, H.K.; Rosen, M.; Lee, R.W.; Scott, H.A. [Lawrence Livermore National Laboratory, California (United States); Tillack, M. [U. C. San Diego, La Jolla, CA (United States)

    2006-06-15

    Underdense radiation sources have been developed to provide efficient laboratory multi-keV radiation sources for radiography and radiation hardening studies. In these plasmas laser absorption by inverse Bremsstrahlung leads to high x-ray conversion efficiency because of efficient ionization of the low density aerogel or gas targets. Now we performing experiments in the soft x-ray energy regime where the atomic physics models are much more complicated. In recent experiments at the NIKE laser, we have irradiated a Ti-doped SiO{sub 2} aerogel with up to 1650 J of 248 nm wavelength light. The absolute Ti L-shell emission in the 200-800 eV range is measured with a diagnostic that uses a transmission grating coupled to Si photodiodes. We will give an overview of the temporally-resolved absolutely calibrated spectra obtained over a range of conditions. (authors)

  12. Trade and transport of radiation sources

    International Nuclear Information System (INIS)

    The guide specifies the obligations pertaining to the trade in and transport of radiation sources and other matters to be taken into account in safety supervision. It also specifies obligations and procedures relating to transfrontier movements of radioactive waste contained in the EU Council Directive 92/3/Euratom. (7 refs.)

  13. Network algorithms for detection of radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Nageswara S.V.; Sen, Satyabrata; Prins, Nicholas J. [Computer Science and Mathematics Div, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Cooper, Daniel A.; Ledoux, Robert J.; Costales, James B.; Kamieniecki, Krzysztof; Korbly, Steven E.; Thompson, Jeffrey K.; Batcheler, James [Passport Systems Inc., N. Billerica, MA 01862 (United States); Brooks, Richard R. [Department of Electrical and Computer Engineering, Clemson University, Clemson, SC 29634 (United States); Wu, Chase Q. [Department of Computer Science, University of Memphis, Memphis, TN 38152 (United States)

    2015-06-01

    Networks of radiation counters have been recently developed for detecting low-level, hazardous radiation sources, and they have been utilized in indoor and outdoor characterization tests. Subsequently, the test measurements have been “replayed” using multiple sub-networks, which enabled the analysis of various scenarios beyond the tests. We present a particle filter algorithm that combines measurements from gamma counters across the network to detect radiation sources. Using replays from an outdoor test, we construct a border monitoring scenario that consists of twelve 2 in.×2 in. NaI detectors or counters deployed on the periphery to monitor a 42×42 m{sup 2} region. A {sup 137}Cs source is moved across this region, starting several meters outside and finally moving away from it. The measurements from individual, pairs and boundary detectors are replayed using the particle filter algorithm. The algorithm outputs demonstrate, both quantitatively and qualitatively, the benefits of networking all boundary counters: the source is detected meters before it enters the region, while being inside, and until moving several meters away. On the other hand, when counters are used individually or in pairs, the source is detected for much shorter durations, and sometimes not detected at all while inside the region.

  14. SOURCE RADIATION AND RESPONSES OF WAVE PROPAGATION

    Institute of Scientific and Technical Information of China (English)

    CHEN; Sheng-zao; Gail; M; Atkinson

    2001-01-01

    Recordings of seismic waves propagating from earthquake source to a station at the earth's surface are a system response function.The convolution operator in time domain can be simplified as a multiplication operator in frequency domain.We discuss in frequency domain the separation of source,path and site effects for global scaling of earthquake source radiation.Also discussed are source scaling model,faulting mechanism,and the H/V inversion problems with crustal and near surface structures.Gross features of apparent source spectra appear to be not much region-dependent although there may be difference between tectonic styles within a region of tectonic mixture for which we need further study as data accumulate.Vertical spectra may be a better approach to approximate source radiation,as it has less crustal amplification effects than horizontal spectra.The H/V ratio is evidently a comprehensive indicator of amplification effects from near surface to deep structure.This gives it potential as an inversion tool to deduce site crustal structure.

  15. Applications and opportunities for radiation sources

    International Nuclear Information System (INIS)

    An important spin-off benefit from the nuclear industry has been the ability to produce a wide variety of ionizing radiation sources for industrial, medical and scientific applications. These sources include radionuclides produced by irradiation of target material in reactors and cyclotrons or recovered from spent fuels, and accelerators. The uses of radiation in both medicine and industry can be expected to evolve. Traditional uses such as cancer therapy will mature and in some cases be displaced by new technology. Major new applications, including food processing and waste treatment, are expected to maintain the demand for isotopes such as cobalt 60 and to stimulate the development of economical and reliable accelerator systems. (L.L.) (Tab., 2 figs.)

  16. Safety of radiation sources in Slovenia

    International Nuclear Information System (INIS)

    The Republic of Slovenia, a central European country which has been independent since 1991, has about 2 million inhabitants and an area of 20,256 km2 . The Constitutional Law on Enforcement of the Basic Constitutional Charter on the Autonomy and Independence of the Republic of Slovenia, adopted on 23 June 1991 (Off. Gaz. of the R of Slovenia No. 1/91), provided that all the laws adopted by the Socialist Federal Republic (SFR) of Yugoslavia should remain in force in the Republic of Slovenia pending the adoption of appropriate legislation by the Slovene Parliament. Under the Slovene Constitution, all international treaties ratified by Slovenia constitute an integral part of Slovenia's legislation and can be applied directly. In Slovenia, all regular types of ionizing radiation source are being used for peaceful purposes and are covered by a system for their safe use and control. All radiation sources and radioactive materials are registered and under regulatory control. Inspections are carried out periodically by the Health Inspectorate of the Republic of Slovenia (HIRS) and, in the case of nuclear installations, the Slovene Nuclear Safety Administration (SNSA). Technical checks on radiation sources are carried out periodically by technical support organizations: the Jozef Stefan Institute and the Institute for Occupational Safety (IOS). (author)

  17. Inductive pulsed power source for plasma radiator

    International Nuclear Information System (INIS)

    The current fed plasmadynamic discharge is used for generation of a wide range of radiation. Such discharges have variable induction and resistance. They therefore require a definite power source to transfer energy with high efficiency. It is known that inductive storage has the larger specific energy capacity in comparison with capacitive energy storage, and better power matching. Therefore an inductive pulsed power source with current multiplication by sectioned inductive storage was designed to feed the plasma flow switch, using explosive switching technology. This report describes the design and the parameters of the inductive energy storage system, and the switches, and the test results for the model- source, where the energy scale is 1:20

  18. Sources of radiation from neutron stars

    CERN Document Server

    Schutz, B F

    1998-01-01

    I give a brief introduction to the problem of detecting gravitational radiation from neutron stars. After a review of the mechanisms by which such stars may produce radiation, I consider the different search strategies appropriate to the different kinds of sources: isolated known pulsars, neutron stars in binaries, and unseen neutron stars. The problem of an all-sky survey for unseen stars is the most taxing one that we face in analysing data from interferometers. I describe the kinds of hierarchical methods that are now being investigated to reach the maximal sensitivity, and I suggest a replacement for standard Fourier-transform search methods that requires fewer floating-point operations for Fourier-based searches over large parameter spaces, and in addition is highly parallelizable, working just as well on a loosely coupled network of workstations as on a tightly coupled parallel computer.

  19. 21 CFR 886.5100 - Ophthalmic beta radiation source.

    Science.gov (United States)

    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...

  20. Seeding Coherent Radiation Sources with Sawtooth Modulation

    Energy Technology Data Exchange (ETDEWEB)

    Ratner, Daniel; Chao, Alex; /SLAC

    2012-03-28

    Seed radiation sources have the ability to increase longitudinal coherence, decrease saturation lengths, and improve performance of tapering, polarization control and other FEL features. Typically, seeding schemes start with a simple sinusoidal modulation, which is manipulated to provide bunching at a high harmonic of the original wavelength. In this paper, we consider seeding from sawtooth modulations. The sawtooth creates a clean phase space structure, providing a maximal bunching factor without the need for an FEL interaction. While a pure sawtooth modulation is a theoretical construct, it is possible to approach the waveform by combining two or more of the composite wavelengths. We give examples of sawtooth seeding for HGHG, EEHG and other schemes, and note that the sawtooth modulation may aid in suppression of the microbunching instability.

  1. Establishing control over nuclear materials and radiation sources in Georgia

    International Nuclear Information System (INIS)

    Regulatory control over radiation sources in Georgia was lost after disintegration of the Soviet Union. A number of radiation accidents and illegal events occurred in Georgia. From 1999 Nuclear and Radiation Safety Service of the Ministry of Environmental Protection and Natural Resources is responsible for regulatory control over radiation sources in Georgia. US NRC Regulatory Assistance Program in Georgia Assist the Service in establishing long term regulatory control over sources. Main focuses of US NRC program are country-wide inventory, create National Registry of sources, safe storage of disused sources, upgrade legislation and regulation, implementation licensing and inspection activities

  2. Methods to identify and locate spent radiation sources

    International Nuclear Information System (INIS)

    The objective of this manual is to provide essential guidance to Member States with nuclear applications involving the use of a wide range of sealed radiation sources on the practical task of physically locating spent radiation sources not properly accounted for. Advice is also provided to render the located source safe on location. Refs, figs, tabs

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

    Science.gov (United States)

    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.

  4. Radiological control in fires involving radiation sources

    International Nuclear Information System (INIS)

    The copies used during the chatter by techniques from CDTN in the I Mineiro Symposium of Fire Engineering, are presented. The chatter was based on emergency radiation control course, given by CDTN. Basic concepts, such as nuclear physics fundaments, radiation nature and detection, radiation protection and practical aspects of radiological fire emergency, were enphasized. (M.C.K.)

  5. Nature and magnitude of the problem of spent radiation sources

    International Nuclear Information System (INIS)

    Various types of sealed radiation sources are widely used in industry, medicine and research. Virtually all countries have some sealed sources. The activity in the sources varies from kilobecquerels in consumer products to hundreds of pentabecquerels in facilities for food irradiation. Loss or misuse of sealed sources can give rise to accidents resulting in radiation exposure of workers and members of the general public, and can also give rise to extensive contamination of land, equipment and buildings. In extreme cases the exposure can be lethal. Problems of safety relating to spent radiation sources have been under consideration within the Agency for some years. The first objective of the project has been to prepare a comprehensive report reviewing the nature and background of the problem, also giving an overview of existing practices for the management of spent radiation sources. This report is the fulfilment of this first objective. The safe management of spent radiation sources cannot be studied in isolation from their normal use, so it has been necessary to include some details which are relevant to the use of radiation sources in general, although that area is outside the scope of this report. The report is limited to radiation sources made up of radioactive material. The Agency is implementing a comprehensive action plan for assistance to Member States, especially the developing countries, in all aspects of the safe management of spent radiation sources. The Agency is further seeking to establish regional or global solutions to the problems of long-term storage of spent radiation sources, as well as finding routes for the disposal of sources when it is not feasible to set up safe national solutions. The cost of remedial actions after an accident with radiation sources can be very high indeed: millions of dollars. If the Agency can help to prevent even one such single accident, the cost of its whole programme in this field would be more than covered. Refs

  6. ORAL ISSUE OF THE JOURNAL "USPEKHI FIZICHESKIKH NAUK": Ginzburg's invention of undulators and their role in modern synchrotron radiation sources and free electron lasers

    Science.gov (United States)

    Kulipanov, Gennadii N.

    2007-04-01

    Undulators — periodic magnetic structures that were originally introduced by Vitalii Ginzburg in 1947 for electromagnetic radiation generation using relativistic electrons — are among the key elements of modern synchrotron radiation sources and free electron lasers (FELs). In this talk, the history of three generations of storage ring-based synchrotron X-ray sources using wigglers and undulators is briefly traced. Prospects for two types of next-generation space-coherent X-ray sources are discussed, which use long undulators and energy recovery accelerators or, alternatively, employ linear accelerator-based FELs. The recently developed Novosibirsk terahertz FEL facility, currently the world' s most powerful terahertz source, is described. It was the generation of electromagnetic radiation in this range that Ginzburg discussed in his 1947 work.

  7. Natural radiation source fabricated from commercially available instant coffee

    International Nuclear Information System (INIS)

    Commercially available instant coffee, Nescafe Excella, contained the radionuclide 40K. From the instant coffee, sixteen coffee-block radiation sources were successfully fabricated with sufficiently low production dependences. The coffee-block radiation sources were examined their suitability for a radiation protection course. Although a part of radiation counts(cpm) obtained with 1 minute measurement were largely deviated, those determined by 5 minute measurements and five times of 1 minute measurement were less deviated, enabling better comprehension of the three cardinal principles of radiation protection. (author)

  8. Indirect detection of radiation sources through direct detection of radiolysis products

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Sterilization plants equipped with the isotopic gamma radiation sources

    International Nuclear Information System (INIS)

    Presentation describes different isotopic gamma radiation sources applicable for sterilization of food and medical materials. Certain gamma pallet irradiators, mini gamma irradiators and different scale gamma tote irradiators are presented. It is concluded, that about two hundreds plants with gamma radiation sources operates in different countries. However, industrially developed countries must construct much more plants than operates now

  10. Transition undulator radiation as bright infrared sources

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.J. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    Undulator radiation contains, in addition to the usual component with narrow spectral features, a broad-band component in the low frequency region emitted in the near forward direction, peaked at an angle 1/{gamma}, where {gamma} is the relativistic factor. This component is referred to as the transition undulator radiation, as it is caused by the sudden change in the electron`s longitudinal velocity as it enters and leaves the undulator. The characteristic of the transition undulator radiation are analyzed and compared with the infrared radiation from the usual undulator harmonics and from bending magnets.

  11. III. Artificial sources of ionizing radiation

    International Nuclear Information System (INIS)

    A theoretical explanation is given of obtaining electrons by thermal emission. The Coolidge X-ray tube is described. The spectral composition is presented of X radiation, changes in the spectrum of X radiation bremsstrahlung in dependence on anode potential and on different shapes of the rectifier of the high voltage curve. X-ray spectrography of crystals is presented as an example of the use of X radiation. Linear accelerators (simple and multiple), microtrons, cyclotrons and betatrons are used for obtaining higher energy radiation. The principle is given for each accelerator and examples of acclerators are given such as are used in clinical practice and in radiotherapy. (E.S.)

  12. Transition undulator radiation as bright infrared sources

    International Nuclear Information System (INIS)

    Undulator radiation contains, in addition to the usual component with narrow spectral features, a broad-band component in the low frequency region emitted in the near forward direction, peaked at an angle 1/γ, where γ is the relativistic factor. This component is referred to as the transition undulator radiation, as it is caused by the sudden change in the electron's longitudinal velocity as it enters and leaves the undulator. The characteristics of the transition undulator radiation are analyzed and compared with the infrared radiation from the usual undulator harmonics and from bending magnets

  13. Regulatory infrastructure for the control of radiation sources in Madagascar

    International Nuclear Information System (INIS)

    Radiation sources are widely used in medicine, industry, research and education in Madagascar. Safety and security of these sources are the main statutory functions of the Regulatory Authority as defined by the regulations in Radiation Protection in Madagascar. These functions are carried out through the system of notification, authorization and inspection, inventory of radiation source and emergency preparedness. The law no. 97-041 on radiation protection and radioactive waste management in Madagascar was promulgated on 2nd January 1998. It governs all activities related to the peaceful use of nuclear energy in Madagascar in order to protect the public, the environment and for the safety of radiation sources. This law complies with the International Basic Safety Standards for protection against ionising Radiation and for the Safety of Radiation Sources (BSS, IAEA Safety Series no. 115). Following the promulgation of the law, four decrees have been enacted by the Malagasy Government. With an effective implementation of these decrees, the ANPSR will be the Highest Administrative Authority in the Field of Radiation Protection and Waste Management in Madagascar. This body is supported by an Executive Secretariat, assisted by the OTR for Radiation Protection and the OCGDR for Waste Management.The paper includes an overview of the Regulatory infrastructure and the organizations of radiation protection in Madagascar. (author)

  14. The safety of radiation sources and radioactive materials in China

    International Nuclear Information System (INIS)

    The report describes the present infrastructure for the safety of radiation sources in China, where applications of radiation sources have become more and more widespread in the past years. In particular, it refers to the main functions of the National Nuclear Safety Administration of the State Environmental Protection Administration (SEPA), which is acting as the regulatory body for nuclear and radiation safety at nuclear installations, the Ministry of Public Health which issues licences for the use of radiation sources, and the Ministry of Public Security, which deals with the security of radiation sources. The report also refers to the main requirements of the existing regulatory system for radiation safety, i.e. the basic dose limits for radiation workers and the public, the licensing system for nuclear installations and for radioisotope-based and other irradiation devices, and the environmental impact assessment system. Information on the nationwide survey of radiation sources carried out by SEPA in 1991 is provided, and on some accidents that occurred in China due to loss of control of radiation sources and errors in the operation of irradiation facilities. (author)

  15. Separation of radiation from two sources from their known radiated sum field

    DEFF Research Database (Denmark)

    Laitinen, Tommi; Pivnenko, Sergey

    2011-01-01

    This paper presents a technique for complete and exact separation of the radiated fields of two sources (at the same frequency) from the knowledge of their radiated sum field. The two sources can be arbitrary but it must be possible to enclose the sources inside their own non-intersecting minimum...

  16. Large area radiation source for water and wastewater treatment

    Science.gov (United States)

    Mueller, Michael T.; Lee, Seungwoo; Kloba, Anthony; Hellmer, Ronald; Kumar, Nalin; Eaton, Mark; Rambo, Charlotte; Pillai, Suresh

    2011-06-01

    There is a strong desire for processes that improve the safety of water supplies and that minimize disinfection byproducts. Stellarray is developing mercury-free next-generation x-ray and UV-C radiation sources in flat-panel and pipe form factors for water and wastewater treatment applications. These new radiation sources are designed to sterilize sludge and effluent, and to enable new treatment approaches to emerging environmental concerns such as the accumulation of estrogenic compounds in water. Our UV-C source, based on cathodoluminescent technology, differs significantly from traditional disinfection approaches using mercury arc lamps or UV LEDs. Our sources accelerate electrons across a vacuum gap, converting their energy into UV-C when striking a phosphor, or x-rays when striking a metallic anode target. Stellarray's large area radiation sources for wastewater treatment allow matching of the radiation source area to the sterilization target area for maximum coverage and improved efficiency.

  17. Radiation Protection for Manned Interplanetary Missions - Radiation Sources, Risks, Remedies

    Science.gov (United States)

    Facius, R.; Reitz, G.

    Health risks in interplanetary explorative missions differ in two major features significantly from those during the manned missions experienced so far. For one, presently available technologies lead to durations of such missions significantly longer than so far encountered - with the added complication that emergency returns are ruled out. Thus radiation exposures and hence risks for late radiation sequelae like cancer increase proportional to mission duration - similar like most other health and many technical risks too. Secondly, loss of the geomagnetic shielding available in low earth orbits (LEO) does increase the radiation dose rates from galactic cosmic rays (GCR) since significant fractions of the GCR flux below about 10 GeV/n now can reach the space vehicle. In addition, radiation from solar particle events (SPE) which at most in polar orbit segments can contribute to the radiation exposure during LEO missions now can reach the spaceship unattenuated. Radiation doses from extreme SPEs can reach levels where even early acute radiation sickness might ensue - with the added risks from potentially associated crew performance decrements. In contrast to the by and large predictable GCR contribution, the doses and hence risks from large SPEs can only stochastically be assessed. Mission designers face the task to contain the overall health risk within acceptable limits. Towards this end they have to transport the particle fluxes of the radiation fields in free space through the walls of the spaceship and through the tissue of the astronaut to the radiation sensitive organs. To obtain a quantity which is useful for risk assessment, the radiobiological effectiveness as well as the specific sensitivity of a given organ has to be accounted for in such transport calculations which of course require a detailed knowledge of the spatial distribution and the atomic composition of the surrounding shielding material. In doing so the mission designer encounters two major

  18. State Register of Sources of Ionizing Radiation and Occupational exposure

    CERN Document Server

    2002-01-01

    One of main tasks of Radiation Protection Centre is to collect, process, systematize, store and provide the data on sources of ionizing radiation and occupational exposures. The number of sources in 2002 is provided and compared with previous year. Distribution of workers according to the type of practice is compared with previous year. Distribution of sealed sources and x-ray machines according their use is presented.

  19. Radiation sources and diagnostics with ultrashort electron bunches

    Energy Technology Data Exchange (ETDEWEB)

    Catravas, P.; Esarey, E.; Leemans, W.P.

    2001-11-02

    The basic principles and design of radiation sources (transition radiation, Cerenkov radiation, radiation from periodic structures, etc.) and radiation-based diagnostics will be discussed, with emphasis on radiation from ultra-short electron bunches. Ultra-short electron bunches have the potential to produce high peak flux radiation sources that cover wavelength regimes where sources are currently not widely available (coherent THz/IR) as well as ultrashort X-ray pulses (3-100 fs). While radiation from the electron bunch contains the full signature of the electron beam and/or medium it has travelled through, the deconvolution of a single property of interest can be difficult due to a large number of contributing properties. The experimental implementation of novel solutions to this problem will be described for beams from 30 MeV to 30 GeV, including fluctuational interferometry, source imaging, phase matched cone angles and laser-based techniques, which utilize optical transition radiation, wiggler and Cerenkov radiation, and Thomson scattering. These novel diagnostic methods have the potential to resolve fs bunch durations, slice emittance on fs scales, etc. The advantages and novel features of these techniques will be discussed.

  20. The regulatory control of ionizing radiation sources in Lithuania

    International Nuclear Information System (INIS)

    The Radiation Protection Centre of the Ministry of Health is the regulatory authority responsible for radiation protection of the public and of workers using sources of ionizing radiation in Lithuania. One of its responsibilities is the control of radioactive sources, which includes keeping the registry, investigating persons arrested while illegally carrying or in possession of radioactive material, decision making and control of users of radioactive sources. The computer based registry contains a directory of more than 24,000 sources and some 800 users in research, medicine and industry. Most of these sources are found in smoke detectors and X ray equipment. The potentially most dangerous sources for therapy and industry (sealed and unsealed) are also listed in this registry. Problems connected with the regulatory control of radioactive sources in Lithuania are presented and their solution is discussed. (author)

  1. Introduction to radiation protection practical knowledge for handling radioactive sources

    CERN Document Server

    Grupen, Claus

    2010-01-01

    The book presents an accessible account of the sources of ionising radiation and the methods of radiation protection. The basics of nuclear physics which are directly related to radiation protection are briefly discussed. The book describes the units of radiation protection, the measurement techniques, biological effects of radiation, environmental radiation, and many applications of radiation. For each chapter there is a problem section with full solutions. A detailed glossary and many useful information in appendixes complete the book. The author has addressed the issue of internationality to make sure that the text and, in particular, the complicated regulations can be easily interpreted not only in Europe and the United States but also in other countries. The subject of radiation protection requires a certain amount of mathematics. For those who have forgotten the basic rules of calculus a short refresher course in the form of a mathematical appendix is added.

  2. Synchrotron radiation sources INDUS-1 and INDUS-2

    International Nuclear Information System (INIS)

    The synchrotron radiation sources, INDUS-1 and INDUS-2 are electron storage rings of 450 MeV and 2 GeV beam energies respectively. INDUS-1 is designed to produce VUV radiation whereas INDUS-2 will be mainly used to produce x-rays. INDUS-1 is presently undergoing commissioning whereas INDUS-2 is under construction. Both these rings have a common injector system comprising of a microtron and a synchrotron. Basic design features of these sources and their injector system are discussed in this paper. The radiation beamlines to be set up on these sources are also described. (author)

  3. Stability of high-brilliance synchrotron radiation sources

    International Nuclear Information System (INIS)

    This paper discusses the following topics: characteristics of synchrotron radiation sources; stability of the orbits; orbit control; nonlinear dynamic stability; and coherent stability and control. 1 ref., 5 figs., 1 tab

  4. Rules and regulations on ionizing radiations sources installations

    International Nuclear Information System (INIS)

    The finality of this legislative text is to establish the standards and procedures for site, design, building, operation and decommissioning of nuclear installations, radioactive installations and ionizing radiations sources. This text include the commercialization of radioactive substances and equipment fabrication

  5. Detecting small low emission radiating sources

    CERN Document Server

    Allmaras, Moritz; Hristova, Yulia; Kanschat, Guido; Kuchment, Peter

    2010-01-01

    The article addresses the possibility of robust detection of geometrically small, low emission sources on a significantly stronger background. This problem is important for homeland security. A technique of detecting such sources using Compton type cameras is developed, which is shown on numerical examples to have high sensitivity and specificity and also allows to assign confidence probabilities of the detection. 2D case is considered in detail.

  6. Background radiation and man-made and sources of radiation

    International Nuclear Information System (INIS)

    This paper describes the development of the use of the atom and its present applications in food and agriculture, industry medicine and health care, energy-environment and research. These applications have inevitably led to concerns about nuclear safety and radioactive waste management and the need for the adoption of procedures for control, safe use and disposal of radioactive sources

  7. Elastic Wave Radiation from a Line Source of Finite Length

    Energy Technology Data Exchange (ETDEWEB)

    Aldridge, D.F.

    1998-11-04

    Straightforward algebraic expressions describing the elastic wavefield produced by a line source of finite length are derived in circular cylindrical coordinates. The surrounding elastic medium is assumed to be both homogeneous and isotropic, anc[ the source stress distribution is considered axisymmetic. The time- and space-domain formulae are accurate at all distances and directions from the source; no fa-field or long-wavelength assumptions are adopted for the derivation. The mathematics yield a unified treatment of three different types of sources: an axial torque, an axial force, and a radial pressure. The torque source radiates only azirnuthally polarized shear waves, whereas force and pressure sources generate simultaneous compressional and shear radiation polarized in planes containing the line source. The formulae reduce to more familiar expressions in the two limiting cases where the length of the line source approaches zero and infinity. Far-field approximations to the exact equations indicate that waves radiated parallel to the line source axI.s are attenuated relative to those radiated normal to the axis. The attenuation is more severe for higher I?equencies and for lower wavespeeds. Hence, shear waves are affected more than compressional waves. This fi-equency- and directiondependent attenuation is characterized by an extremely simple mathematical formula, and is readily apparent in example synthetic seismograms.

  8. Diffractive triangulation of radiative point sources

    CERN Document Server

    Vespucci, Stefano; Maneuski, Dzmitry; O'Shea, Val; Winkelmann, Aimo

    2016-01-01

    We describe a general method to determine the location of a point source of waves relative to a two-dimensional active pixel detector. Based on the inherent structural sensitivity of crystalline sensor materials, characteristic detector diffraction patterns can be used to triangulate the location of a wave emitter. As a practical application of the wide-ranging principle, a digital hybrid pixel detector is used to localize a source of electrons for Kikuchi diffraction pattern measurements in the scanning electron microscope. This provides a method to calibrate Kikuchi diffraction patterns for accurate measurements of microstructural crystal orientations, strains, and phase distributions.

  9. Evaluation of radiation source term for the DUPIC fuel core

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Bok; Ryu, Ho Jin; Park, Chang Je

    2004-12-01

    The radiation source term of the DUPIC fuel CANDU reactor was estimated for the total and gap inventories of fission products. The calculation was performed by the ELESTRES code using fuel burnup and linear power distribution obtained from the reactor physics calculations. The radiation source term represented by the fission products gap inventory was 46912 TBq for the 1/4 DUPIC fuel core, while it was 75448 TBq for the natural uranium core. Such a reduction of the radiation source term for the DUPIC fuel core can be attributed to the lower linear power of the DUPIC fuel bundle caused by the flattened power distribution of the DUPIC fuel core which adopts a 2-bundle shift refueling scheme. It is therefore expected that the consequence of the loss of coolant accident for the DUPIC fuel core could be weak when compared to the natural uranium core from the viewpoint of radiation doses to the public.

  10. Training of human resources on radiation protection and safe use of radiation sources. Argentine experience

    International Nuclear Information System (INIS)

    Argentina has a long experience in Radiation Protection training since 25 years ago. In the present work we analyse those variable and non variable training aspects according to scientific development, increasing radiation source diversity (including new concepts like orphan sources and security), mayor concern about patient in Radiation Protection, previous exposures, etc. We comment what we consider the main steps in the training of Radiation Protection specialists, like university degree, post graduate education distinguishing between formative and informative contents and on the job training. Moreover, we point out the trainees aptitudes and attitudes to be developed in order to work properly in this interdisciplinary field. (author)

  11. Ionizing radiation sources used in medical applications in Brazil

    International Nuclear Information System (INIS)

    Preliminary data about ionizing radiation sources used in medical applications and obtained through a national programme by IRD/CNEN together with Brazilian health authorities are presented. The data presentation follows, as close as possible, recommendations given by the United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR). This programme has two main aims: First: to contribute for research in the field of ionizing radiation effects and risks including information about equipment quality control and procedures adopted by professionals working in Radiation Medicine. Second: to investigate the radiation protection status in Brazil, in order to give assistance to Brazilian health authorities for planning regional radiation programmes and training programmes for medical staffs. (F.E.). 13 refs, 19 figs, 34 tabs

  12. Solar radiation data sources, applications, and network design

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-04-01

    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 about 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.

  13. Radiation protection and regulatory aspects in the use of radiation sources

    International Nuclear Information System (INIS)

    The uses of ionising radiation sources (i.e. radioisotopes and radiation generating equipment such as accelerators and X-ray machines) for multifarious applications in industry, medicine, agriculture, research and teaching have been significantly increasing all over the world. In India, the application of radiation sources in various fields has registered phenomenal growth during the last decade. The use of radiation sources mainly include radiation processing for food preservation and sterilization of healthcare products, radiotherapy for treatment of cancer, nuclear medicine for diagnosis and therapy, gamma chambers for several R and D studies, blood irradiators, industrial radiography for non destructive examinations of steel structures, industrial ionising radiation gauging devices for monitoring/measurement of on-line quality control parameters (e.g. thickness, level, density, moisture, elemental analysis), consumer products such as gaseous tritium light sources (GTLS), gaseous tritium light devices (GTLD), ionisation chamber smoke detectors (ICSD), fluorescent light starters, antistatic devices and incandescent gas mantles containing thorium etc. All these beneficial applications involve use of both sealed and unsealed radioactive sources and amount of radioactivity varies from few kBq (μCi) to hundreds of TBq (thousands of curies). Radiation sources emit ionising radiations and if not handled properly and safely, may give rise to potential exposures leading to an unacceptable hazard. Therefore, it is necessary to ensure a high standard of safety and reliability in handling of radiation equipment and sources through their careful design by ensuring adequate built-in-safety as per applicable national/international standard, safe operation and periodic maintenance procedures, safe transport from one place to another, secured storage when not in use, physical security to radiation sources, effective emergency response plans and preparedness, including safe

  14. Radiating sources in higher-dimensional gravity

    OpenAIRE

    Liu, Hongya; Wesson, Paul S.

    2001-01-01

    We study a time-dependent 5D metric which contains a static 4D sub-metric whose 3D part is spherically symmetric. An expansion in the metric coefficient allow us to obtain close-to Schwarzschild approximation to a class of spherically-symmetric solutions. Using Campbell's embedding theorem and the induced-matter formalism we obtain two 4D solutions. One describes a source with the stiff equation of state believed to be applicable to dense astrophysical objects, and the other describes a spher...

  15. Possible sources of radiation in indoor environment

    International Nuclear Information System (INIS)

    More locations and building material will be needed to solve the housing needs, actually the future quantities will equal the total of all the previous building. And presently one quarter of the world population is already homeless. The development of human civilization in the new technological era goes on extremely quickly. In the search for new spaces, in the last decade of the 20th century, in town renovation planning the application of subterranean civil engineering is very popular. Below ground level, the new towns are built with many stories, with exclusively artificial light and artificial climate. There is not the slightest possibility of natural ventilation. These spaces have not been investigated as regards the contents of radon. Man is not adapted to spend most of the time in under artificial conditions. It is still to be discovered how it will affect humans and what is the degree of exposure to ionizing radiation in such conditions. It might be better to abandon underground construction before the adverse effects are proved. Previous mistakes in building must be overcome and new technologies applied as well as sustainable development in the future. (author)

  16. Environmental radiation safety source term evaluation program

    International Nuclear Information System (INIS)

    Plutonium-238 is currently used in the form of a pure refractory oxide as a power source on a number of space vehicles that have already been or will be launched during the next few years. Although the sources are designed and built to withstand re-entry into the earth's atmosphere and impact with the earth's surface without releasing any plutonium, the possibility of such an event can never be absolutely excluded. Three separate tasks were undertaken in this study. The interactions between soils and 238PuO2 aerosols which might be created in a space launch about environment were examined. Aging of the plutonium-soil mixture under a humid atmosphere showed a trend toward the slow coagulation of two dilute aerosols. Studies on marine animals were conducted to assess the response of 238PuO2 pellets to conditions found 60 feet below the ocean surface. Ultrafilterability studies measured the solubility of 238PuO2 as a function of time, temperature, suspension concentration and molality of solvent

  17. Postgraduate educational course in radiation protection and the safety of radiation sources. Standard syllabus

    International Nuclear Information System (INIS)

    The aim of the Postgraduate Educational Course in Radiation Protection and the Safety of Radiation Sources is to meet the needs of professionals at graduate level, or the equivalent, for initial training to acquire a sound basis in radiation protection and the safety of radiation sources. The course also aims to provide the necessary basic tools for those who will become trainers in radiation protection and in the safe use of radiation sources in their countries. It is designed to provide both theoretical and practical training in the multidisciplinary scientific and/or technical bases of international recommendations and standards on radiation protection and their implementation. The participants should have had a formal education to a level equivalent to a university degree in the physical, chemical or life sciences or engineering and should have been selected to work in the field of radiation protection and the safe use of radiation sources in their countries. The present revision of the Standard Syllabus takes into account the requirements of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS), IAEA Safety Series No. 115 (1996) and recommendations of related Safety Guides, as well as experience gained from the Postgraduate Educational Course on Radiation Protection and Safety of Radiation Sources held in several regions in recent years. The general aim of the course, as mentioned, is the same. Some of the improvements in the present version are as follows: The learning objective of each part is specified. The prerequisites for each part are specified. The structure of the syllabus has been changed: the parts on Principles of Radiation Protection and on Regulatory Control were moved ahead of Dose Assessment and after Biological Effects of Radiation. The part on the interface with nuclear safety was dropped and a module on radiation protection in nuclear power plants has been included. A

  18. Control of radioisotopes and radiation sources in Indonesia

    International Nuclear Information System (INIS)

    Radioisotopes and radiation sources are extensively used in Indonesia in medicine, industry, mining, agriculture and research. These materials are controlled by the regulatory authority, according to established legal procedures. The Nuclear Energy Control Board of Indonesia (BAPETEN), which was established in 1998 through the Nuclear Energy Act No. 10/1997, is entrusted with the control of any application of nuclear energy, including the application of radioisotopes and radiation sources, through regulation, licensing and inspection. The control is aimed to assure welfare, security and peace, the safety and health of workers and the public, and environmental protection. The number of licences issued to date is around 2400, consisting of 1600 licences for radioisotopes and radiation sources used in hospitals, 347 in radiography, 256 in industry, 53 in mining, and the rest in many other areas such as research and agriculture. A licence can cover one or more radioisotopes or radiation sources, depending on the location of the user institution. These radioisotopes and radiation sources are Co-60, Cs-137, Ir-192, Ra-226, Am-241, Sr-90, Kr-85, Pm-147, linear accelerator and X-ray, and short half-life radioisotopes such as I-125, I-131 and Tc-99m. There are 10 LINACs, 27 X-ray medicines, 61 radioisotope devices for Co-60 and Cs-137, and 10 mHDR Ir-192 for therapeutic purposes currently used in Indonesia and some Ra-226 in storage. Any activity related to the application of nuclear energy is required to be conducted in a manner which observes safety and security. According to the legal requirements, each user has to employ at least one radiation safety officer. To improve the control of the application of radiation sources and radioactive material in the country, BAPETEN introduced some new approaches to the users, including regular dialogues with radiation safety officers and the management of the users, requalification for radiation protection officers twice in five

  19. Exposure of the Spanish population to radiation from natural sources

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Talavera, M.; Suarez, E.; Matarranz, J.L.; Salas, R.; Ramos, L. [Consejo de Seguridad Nuclear. Justo Dorado, Madrid (Spain)

    2006-07-01

    We have assessed the exposure of the Spanish population to natural radiation sources. The annual average effective dose is estimated to be 2.38 mSv, taking into account contributions from cosmic radiation (13.8%), terrestrial gamma radiation (39%), radon and thoron inhalation (34%) and ingestion (13.2%). Cosmic radiation doses were calculated from town altitude data. Terrestrial gamma ray exposure outdoors was derived from the M.A.R.N.A. (natural gamma radiation map of Spain). Indoor gamma ray exposure was calculated by multiplying the corresponding outdoor value conversion factor, which was obtained by a linear least-squares fit of experimental measurements. Radon doses were estimated from national surveys carried out throughout the country. To assess doses by ingestion of water and foodstuffs we considered the results from a detailed study on consumption habits by age and geographical area in Spain, promoted by C.S.N., and average radioactivity values from UNSCEAR. (authors)

  20. Radiation problems expected for the German spallation neutron source

    International Nuclear Information System (INIS)

    The German project for the construction of a Spallation Neutron Source with high proton beam power (5.5 MW) will have to cope with a number of radiation problems. The present report describes these problems and proposes solutions for keeping exposures for the staff and release of activity and radiation into the environment as low as reasonably achievable. It is shown that the strict requirements of the German radiation protection regulations can be met. The main problem will be the exposure of maintenance personnel to remanent gamma radiation, as is the case at existing proton accelerators. Closed ventilation and cooling systems will reduce the release of (mainly short-lived) activity to acceptable levels. Shielding requirements for different sections are discussed, and it is demonstrated by calculations and extrapolations from experiments that fence-post doses well below 150 mrem/y can be obtained at distances of the order of 100 metres from the principal source points. The radiation protection system proposed for the Spallation Neutron Source is discussed, in particular the needs for monitor systems and a central radiation protection data base and alarm system. (orig.)

  1. Producing terahertz coherent synchrotron radiation at the Hefei Light Source

    Institute of Scientific and Technical Information of China (English)

    XU De-Rong; XU Hong-Liang; SHAO Yan

    2015-01-01

    This paper theoretically proves that an electron storage ring can generate coherent radiation in the THz region using a quick kicker magnet and an AC sextupole magnet.When the vertical chromaticity is modulated by the AC sextupole magnet,the vertical beam collective motion excited by the kicker produces a wavy spatial structure after a number of longitudinal oscillation periods.The radiation spectral distribution was calculated from the wavy bunch parameters at the Hefei Light Source (HLS).When the electron energy is reduced to 400 MeV,extremely strong coherent synchrotron radiation (CSR) at 0.115 THz should be produced.

  2. Producing Terahertz Conherent Synchrotron Radiation Based On Hefei Light Source

    CERN Document Server

    De-Rong, Xu; Yan, Shao

    2014-01-01

    This paper theoretically proves that an electron storage ring can generate coherent radiation in THz region using a quick kicker magnet and an ac sextupole magnet. When the vertical chromaticity is modulated by the ac sextupole magnet, the vertical beam collective motion excited by the kicker produces a wavy spatial structure after a number of longitudinal oscillation periods. We calculate the radiation spectral distribution from the wavy bunch in Hefei Light Source(HLS). If we reduce electron energy to 400MeV, it can produce extremely strong coherent synchrotron radiation(CSR) at 0.115THz.

  3. Manufacture of Single 60Co Source Irradiation Facility and the Measurement of Reference Radiation Filed

    Institute of Scientific and Technical Information of China (English)

    GAO; Fei; WANG; Hong-yu; NI; Ning; ZHANG; Li; HOU; Jin-bing; SONG; Ming-zhe

    2012-01-01

    <正>Reference radiation filed produced by isotope source is necessary for calibration of radiation dose meter. 60Co single source radiation facility is an important method to produce reference radiation. Collimation design of the facility is good for characteristics of the field, but there are scattered photon influences however. Scattered radiation is mainly come from collimation, source shield, floor, walls and

  4. MCNP model for the many KE-Basin radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Rittmann, P.D.

    1997-05-21

    This document presents a model for the location and strength of radiation sources in the accessible areas of KE-Basin which agrees well with data taken on a regular grid in September of 1996. This modelling work was requested to support dose rate reduction efforts in KE-Basin. Anticipated fuel removal activities require lower dose rates to minimize annual dose to workers. With this model, the effects of component cleanup or removal can be estimated in advance to evaluate their effectiveness. In addition, the sources contributing most to the radiation fields in a given location can be identified and dealt with.

  5. Network detection of radiation sources using ROSD localization

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qishi [University of Memphis; Berry, M. L.. [New Jersey Institute of Technology; Grieme, M. [New Jersey Institute of Technology; Rao, Nageswara S [ORNL; Sen, Satyabrata [ORNL; Brooks, Richard R [Clemson University

    2015-01-01

    We propose a localization-based radiation source detection (RSD) algorithm using the Ratio of Squared Distance (ROSD) method. Compared with the triangulation-based method, the advantages of this ROSD method are multi-fold: i) source location estimates based on four detectors improve their accuracy, ii) ROSD provides closed-form source location estimates and thus eliminates the imaginary-roots issue, and iii) ROSD produces a unique source location estimate as opposed to two real roots (if any) in triangulation, and obviates the need to identify real phantom roots during clustering.

  6. Accelerator based atomic physics experiments: an overview

    International Nuclear Information System (INIS)

    Atomic Physics research with beams from accelerators has continued to expand and the number of papers and articles at meetings and in journals reflects a steadily increasing interest and an increasing support from various funding agencies. An attempt will be made to point out where interdisciplinary benefits have occurred, and where applications of the new results to engineering problems are expected. Drawing from material which will be discussed in the conference, a list of the most active areas of research is presented. Accelerator based atomic physics brings together techniques from many areas, including chemistry, astronomy and astrophysics, nuclear physics, solid state physics and engineering. An example is the use of crystal channeling to sort some of the phenomena of ordinary heavy ion stopping powers. This tool has helped us to reach a better understanding of stopping mechanisms with the result that now we have established a better base for predicting energy losses of heavy ions in various materials

  7. Romanian experience on safety and security of radiation sources

    International Nuclear Information System (INIS)

    Romania has established the first administrative structure for controlling the deployment of the nuclear activities in 1961 and the first Romanian nuclear law was published in 1974. In the present, it is in force the Law no. 111, published in 1996 and republished in 2003. Moreover, there are available facilities and services to the persons authorized to manage radioactive sources. The regulation for safety and security of radioactive sources was amended two times in order to implement the international recommendations for setting up the national system for accounting and control of radiation sources and to coordinate the recovery activities. As part of national control programme, the national inventory of sources and devices is updated permanently, when issuing a new authorization, when modifying an existing one, or when renewing an authorization system and records in the database. The government responsibility for the orphan sources is stated in the law on radioactive waste management and decommissioning fund. There is a protocol between CNCAN, Ministry of Internal and Ministry of Health and Family regarding the co-operation in the case of finding orphan sources. When a radiation source is spent, it becomes radioactive waste that has to be disposed off properly. Depending on the case, the holder of a spent source has the possibility either to return the radioactive source to its manufacturer for regeneration or to transfer it to the Radioactive Waste Treatment Facility. (author)

  8. Thermophotoelectric converter with radioisotope source of thermal radiation

    International Nuclear Information System (INIS)

    Results of investigating a thermophotoelectric converter with a radioisotope heat source to warm up a radiating surface are presented. Results are given of calculating the efficiency of thermophotoelectric converters with germanium and silicon photocells in the temperature range from 1000 to 1300 K, and of the comparative analysis of experimental and theoretical values of thermophotoelectric converter efficiencies. The possibility of developing a thermophotoconverter with a radioisotope source of thermal energy which has an efficiency of up to 15% is substantiated. It is shown that for effective energy conversion at radiator temperatures of 1000-1300 K it is necessary to use Ge, GaSb, InAs, PbS and PbTe semiconducting materials, and to increase to maximum the reflection coefficient of the photocell back contact and the radiation blackness

  9. Terrestrial radiation sources at the place of work

    International Nuclear Information System (INIS)

    An altogether new Part 3 of the draft amendment contains the substantive provisions for ''protection of the population and the environment from the hazards of natural sources of ionizing radiation''. The regulatory provisions have been formulated in compliance with the requirements and principles of the EURATOM Directive. (orig./CB)

  10. 76 FR 6692 - Radiation Sources on Army Land

    Science.gov (United States)

    2011-02-08

    .... Background In the April 14, 2010, issue of the Federal Register (75 FR 19302), the Army issued a proposed..., 2007 (72 FR 55864) that became effective on November 30, 2007. The Army received no comments on its... Department of the Army 32 CFR Part 655 RIN 0702-AA58 Radiation Sources on Army Land AGENCY: Department of...

  11. 75 FR 19302 - Radiation Sources on Army Land

    Science.gov (United States)

    2010-04-14

    ... final rule which establishes requirements for the expanded definition of byproduct material. 72 FR 55864... was made in a separate rulemaking for 10 CFR Part 110 (April 20, 2006; 71 FR 20336). The Department of... Department of the Army 32 CFR Part 655 RIN 0702-AA58 Radiation Sources on Army Land AGENCY: Department of...

  12. Coherent Cherenkov radiation as an intense THz source

    Science.gov (United States)

    Bleko, V.; Karataev, P.; Konkov, A.; Kruchinin, K.; Naumenko, G.; Potylitsyn, A.; Vaughan, T.

    2016-07-01

    Diffraction and Cherenkov radiation of relativistic electrons from a dielectric target has been proposed as mechanism for production of intense terahertz (THz) radiation. The use of an extremely short high-energy electron beam of a 4th generation light source (X-ray free electron laser) appears to be very promising. A moderate power from the electron beam can be extracted and converted into THz radiation with nearly zero absorption losses. The initial experiment on THz observation will be performed at CLARA/VELA FEL test facility in the UK to demonstrate the principle to a wider community and to develop the radiator prototype. In this paper, we present our theoretical predictions (based on the approach of polarization currents), which provides the basis for interpreting the future experimental measurements. We will also present our hardware design and discuss a plan of the future experiment.

  13. A source-attractor approach to network detection of radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qishi [University of Memphis; Barry, M. L.. [New Jersey Institute of Technology; Grieme, M. [New Jersey Institute of Technology; Sen, Satyabrata [ORNL; Rao, Nageswara S [ORNL; Brooks, Richard R [Clemson University

    2016-01-01

    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 require 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.

  14. Small compact pulsed electron source for radiation technologies

    International Nuclear Information System (INIS)

    The small compact pulsed electron source for radiation technologies is considered in the report. The electron source consists of pulsed high voltage Marx generator and vacuum diode with explosive emission cathode. The main parameters of electron source are next: kinetic energy is 100-150 keV, beam current is 5-200 A and pulse duration is 100-400 nsec. The distribution of absorbed doses in irradiated materials is considered. The physical feasibility of pulsed low energy electron beam for applications is considered

  15. Large radiation sources in industry. Proceedings of a conference on the application of large radiation sources in industry. V. I

    International Nuclear Information System (INIS)

    Uses of radiation in industry are among the most effective ways in which atomic energy can help economic development. The benefits to industry, which are already substantial, have so far been mostly derived from the application of radioisotopes and other small sources of radiation as tools of scientific investigation, detection, measurement or control. The use of radiation as a direct agent in initiating industrial processes, which has now become possible with the availability of large radiation sources, will perhaps result in ever greater and wider development. Work in this new field of research and development has already been undertaken in some countries and a beginning is being made in many others. In view of a widely felt need for an exchange of information and views on the new techniques and results, the International Atomic Energy Agency organized a conference at Warsaw in September 1959 on the Application of Large Radiation Sources in Industry and Especially to Chemical Processes. This was the first international scientific meeting at which the whole subject was reviewed in detail.

  16. Materials considerations for molten salt accelerator-based plutonium conversion systems

    International Nuclear Information System (INIS)

    Accelerator-driven transmutation technology (ADTT) refers to a concept for a system that uses a blanket assembly driven by a source of neutrons produced when high-energy protons from an accelerator strike a heavy metal target. One application for such a system is called Accelerator-Based Plutonium Conversion, or ABC. Currently, the version of this concept being proposed by the Los Alamos National Laboratory features a liquid lead target material and a blanket fuel of molten fluorides that contain plutonium. Thus, the materials to be used in such a system must have, in addition to adequate mechanical strength, corrosion resistance to molten lead, corrosion resistance to molten fluoride salts, and resistance to radiation damage. In this report the corrosion properties of liquid lead and the LiF-BeF2 molten salt system are reviewed in the context of candidate materials for the above application. Background information has been drawn from extensive past studies. The system operating temperature, type of protective environment, and oxidation potential of the salt are shown to be critical design considerations. Factors such as the generation of fission products and transmutation of salt components also significantly affect corrosion behavior, and procedures for inhibiting their effects are discussed. In view of the potential for extreme conditions relative to neutron fluxes and energies that can occur in an ADTT, a knowledge of radiation effects is a most important factor. Present information for potential materials selections is summarized

  17. Cumulation in the exposure to sources of ionizing radiation

    International Nuclear Information System (INIS)

    The Dutch National Institute of Public health and Environmental protection (RIVM) has investigated if the maximum permissible risk of 10-6 a-1 for a single source and 10-5a-1 for all sources of ionizing radiation, as defined in the framework of BNS (policy notice regarding the regulation of ionizing radiation), are exceeded in the Dutch population due to the exposure by one single source or all sources respectively. The following sources were considered: radionuclide laboratories, nuclear installations, nuclear waste, sources and devices, conventional energy plants, phosphate fertilizer plants, other non-nuclear industries, transport of radioactive sources and consumer goods. A distinction was made between 'critical' groups due to geographical factors and due to behaviour, such as consumption of special food-stuffs. For risk assessment a uniform risk factor of 0.025 Sv-1 was used, as proposed in BNS. This factor is based on the life-time risk of women and includes the higher risk factors for children. (author). 15 refs.; 4 figs.; 9 tabs

  18. Protection of loading and unloading machines. General considerations, radiation sources

    International Nuclear Information System (INIS)

    The first part of this report states several general considerations regarding the protection during loading and unloading operations of an operating atomic pile, i.e. the introduction of a fuel element or a control bar into a pressurized enclosure, and the removal from a pressurized enclosure of a radioactive element the radioactivity of which decreases, and the transfer of this element into a pool. These handling operations are associated with different risks: external neutron or gamma irradiation, installation contamination, and effluent leakages presenting chemical or radioactive hazards. The authors indicate or address the admissible radiation level, the dose level at the vicinity of loading machines, the distribution of radiation sources, the distribution of dose rates between neutron and gamma rays, the material selection, issues related to heating, the subsequent transfer of the fuel to the storage pool, and the unloading of control bars with non fissile bodies. The second part addresses the radiation sources: gamma radiations from fission product, delayed neutrons, neutrons from the reactor, thermal capture gamma radiations, heating

  19. Nuisance Source Population Modeling for Radiation Detection System Analysis

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-10-05

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

  20. Light-emitting diodes as a radiation source for plants

    Science.gov (United States)

    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.

  1. Operation of INDUS-1, India's first synchrotron radiation source

    International Nuclear Information System (INIS)

    INDUS-1 is a 450 MeV electron storage ring for the production of Synchrotron Radiation in Visible Ultra Violet (VUV) range with a critical wavelength of 61 A deg. The ring was commissioned in June 1999. Since then it is in regular operation. This Synchrotron Radiation Source (SRS) facility consists of a 20 MeV injector microtron, a 450 MeV booster synchrotron and a storage ring. In this paper operation aspects of INDUS-1 SRS facility will be presented. (author)

  2. Radiation efficiency of earthquake sources at different hierarchical levels

    International Nuclear Information System (INIS)

    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

  3. Radiation efficiency of earthquake sources at different hierarchical levels

    Energy Technology Data Exchange (ETDEWEB)

    Kocharyan, G. G., E-mail: gevorgkidg@mail.ru [Institute of Dynamics of Geospheres RAS, Moscow, 119334 (Russian Federation); Moscow Institute of Physics and Technology (State University), Dolgoprudny, 117303 (Russian Federation)

    2015-10-27

    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.

  4. First accelerator-based physics of 2014

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    Experiments in the East Area received their first beams from the PS this week. Theirs is CERN's first accelerator-based physics since LS1 began last year.   For the East Area, the PS performs a so-called slow extraction, where beam is extracted during many revolution periods (the time it take for particles to go around the PS, ~2.1 μs). The yellow line shows the circulating beam current in the PS, decreasing slowly during the slow extraction, which lasts 350 ms. The green line is the measured proton intensity in the transfer line toward the East Area target. Although LHC physics is still far away, we can now confirm that the injectors are producing physics! In the East Area - the experimental area behind the PS - the T9 and T10 beam lines are providing beams for physics. These beam lines serve experiments such as AIDA - which looks at new detector solutions for future accelerators - and the ALICE Inner Tracking System - which tests components for the ALICE experiment. &qu...

  5. Gamma radiation levels from a line source of monazite

    International Nuclear Information System (INIS)

    Monazite contains some 6% thorium and the thorium decay chain gives rise to gamma radiation emissions. It is often desirable to predict the gamma radiation levels associated with the radioactive decay of the thorium chain in monazite, particularly in situations where storage and transport are involved . The mathematics associated with a radioactive line source are considered and an expression is derived for the prediction of gamma radiation levels from the line source. This is applied to practical situations involving monazite and a mathematical model specifically for monazite is developed. As monazite is transported in bulk bags which are placed inside transport containers, beyond a certain distance from such containers or similar storage devices, the monazite may be considered to approximate a line source. The validity of approximating monazite containers to a line source is checked by comparing the gamma levels predicted by the model with those actually measured in a field situation where transport containers of monazite are involved. 2 refs., 3 figs., 2 tabs

  6. Handling radiation generated during an ion source commissioning

    Science.gov (United States)

    Ren, H. T.; Zhao, J.; Peng, S. X.; Lu, P. N.; Zhou, Q. F.; Xu, Y.; Chen, J.; Zhang, T.; Zhang, A. L.; Guo, Z. Y.; Chen, J. E.

    2014-02-01

    Radiation is an important issue, which should be carefully treated during the design and commissioning of an ion source. Measurements show that X-rays are generated around the ceramics column of an extraction system when the source is powered up to 30 kV. The X-ray dose increases greatly when a beam is extracted. Inserting the ceramic column into a metal vacuum box is a good way to block X-ray emission for those cases. Moreover, this makes the online test of an intense H+ ion beam with energy up to 100 keV possible. However, for deuteron ion source commissioning, neutron and gamma-ray radiation become a serious topic. In this paper, we will describe the design of the extraction system and the radiation doses of neutrons and gamma-rays measured at different D+ beam energy during our 2.45 GHz deuteron electron cyclotron resonance ion source commissioning for PKUNIFTY (PeKing University Neutron Imaging FaciliTY) project at Peking University.

  7. Radiological protection issues in endovascular use of radiation sources

    International Nuclear Information System (INIS)

    The use of radiation from radioactive materials for cancer treatment is well established. However, examples of uses of radiation therapy for benign conditions have been limited. Placing a radioactive source in the blood vessel so as to irradiate the surrounding inner periphery of the vessel has been attempted in recent years to prevent restenosis after percutaneous coronary and peripheral interventions. This kind of endovascular application provides treatment options that are less invasive for various vascular conditions compared with open surgery. As a part of the International Atomic Energy Agency's (IAEA) function for providing for application of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) that were jointly sponsored by the IAEA, FAO, ILO, OECD/NEA, PAHO and WHO, the IAEA planned a coordinated research project (CRP) that was to start in 2002 on radiological protection problems in endovascular use of radiation sources. However, as experts soon realized that the interest in this modality was waning, the CRP was not initiated. Nevertheless, it was felt that it would be appropriate to compile the information available on radiological protection problems observed so far and their possible solutions. This work was seen as part of a broader IAEA programme that covered accident prevention in radiotherapy. Publications on this topic have included, inter alia, Lessons Learned from Accidental Exposures in Radiotherapy (Safety Reports Series No. 17); Accidental Overexposure of Radiotherapy Patients in Bialystok; Investigation of an Accidental Exposure of Radiotherapy Patients in Panama; Accidental Overexposure of Radiotherapy Patients in San Jose, Costa Rica; and Investigation of an Accidental Exposure of Radiotherapy Patients in Poland. Keeping in mind that endovascular applications involve specialists such as cardiologists, angiologists and surgeons, all of whom might not have a

  8. Regulatory control of radiation sources in the Philippines

    International Nuclear Information System (INIS)

    This paper is concerned with the radiation protection and safety infrastructure providing emphasis on the regulation and control of radiation sources in the Philippines. It deals with the experiences of the Philippine Nuclear Research Institute, as a regulatory body, in the regulation and control of radioactive materials in radiotherapy, nuclear medicine, industrial radiography, industrial gauges, industrial irradiators, and well logging. This paper includes an inventory of the sources and types of devices/equipment used by licensed users of radioactive materials in the Philippines as a contribution to the data base being prepared by the IAEA. The problems encountered by the regulatory body in the licensing and enforcement process, as well as the lessons learned from incidents involving radioactive materials are discussed. Plans for improving compliance to the regulations and enhancing the effectiveness of PNRI's regulatory functions are presented. (author)

  9. Helium Reionization Simulations. I. Modeling Quasars as Radiation Sources

    CERN Document Server

    La Plante, Paul

    2015-01-01

    We introduce a new project to understand helium reionization using fully coupled $N$-body, hydrodynamics, and radiative transfer simulations. This project aims to capture correctly the thermal history of the intergalactic medium (IGM) as a result of reionization and make predictions about the Lyman-$\\alpha$ forest and baryon temperature-density relation. The dominant sources of radiation for this transition are quasars, so modeling the source population accurately is very important for making reliable predictions. In this first paper, we present a new method for populating dark matter halos with quasars. Our set of quasar models include two different light curves, a lightbulb (simple on/off) and symmetric exponential model, and luminosity-dependent quasar lifetimes. Our method self-consistently reproduces an input quasar luminosity function (QLF) given a halo catalog from an $N$-body simulation, and propagates quasars through the merger history of halo hosts. After calibrating quasar clustering using measurem...

  10. Source term calculations for assessing radiation dose to equipment

    International Nuclear Information System (INIS)

    This study examines results of analyses performed with the Source Term Code Package to develop updated source terms using NUREG-0956 methods. The updated source terms are to be used to assess the adequacy of current regulatory source terms used as the basis for equipment qualification. Time-dependent locational distributions of radionuclides within a containment following a severe accident have been developed. The Surry reactor has been selected in this study as representative of PWR containment designs. Similarly, the Peach Bottom reactor has been used to examine radionuclide distributions in boiling water reactors. The time-dependent inventory of each key radionuclide is provided in terms of its activity in curies. The data are to be used by Sandia National Laboratories to perform shielding analyses to estimate radiation dose to equipment in each containment design. See NUREG/CR-5175, ''Beta and Gamma Dose Calculations for PWR and BWR Containments.'' 6 refs., 11 tabs

  11. Cosmic Radiation Fields: Sources in the early Universe

    Science.gov (United States)

    Raue, Martin; Kneiske, Tanja; Horns, Dieter; Elsaesser, Dominik; Hauschildt, Peter

    The workshop "Cosmic Radiation Fields - Sources in the Early Universe" (CRF 2010) focuses on the connection between the extragalactic infrared background and sources in the early universe, in particular stars powered by dark matter burning (Dark Stars; DS). The workshop covers the following topics: the cosmic infrared background, formation of early stars, dark stars, effect of dark matter in the early universe, dark matter halos, primordial star formation rate, and reionization. Further information can be found on the conference webpage: http://www.desy.de/crf2010/. Organizing committee: Tanja Kneiske, Martin Raue, Dominik Elsaesser, Alexander Gewering-Peine, Peter Hausschildt, Dieter Horns, and Andreas Maurer.

  12. RF gun for an intense THz radiation source

    Institute of Scientific and Technical Information of China (English)

    GU Qiang; ZHAO Zhen-Tang; TONG De-Chun; CHEN Li-Fang; XU Xiu-Min

    2008-01-01

    A new facility is under construction at the Shanghai Institute of Applied Physics,to generate femto-second electron bunches and intense coherent THz radiation pulses.A thermionic RF-gun is used to be the electron source of the linac,which is 1.6 cell,π/2,side coupled in design.In the following of this paper,the design,manufacture and beam operation of this gun are presented.

  13. Experiments planned to be made with the synchrotron radiation source

    International Nuclear Information System (INIS)

    For this working meeting, various research groups from the Land Sachsen and from the neighbouring countries Poland and the Czech Republic have been invited in order to present their materials research programmes or task-specific experiments intended to be carried out with the synchrotron radiation source to be installed in the near future. The proceedings volume in hand presents the discussion papers, which have been directly reproduced from the original foils. (orig.)

  14. Sources and effects of ionizing radiation. UNSCEAR 2000 report to the General Assembly, with scientific annexes. Volume I: Sources

    International Nuclear Information System (INIS)

    Over the past few years the United Nations Scientific Committee on the effects of Atomic Radiation has undertaken a broad review of the sources and effects of ionizing radiation. In the present report, the Committee, drawing on the main conclusions of its scientific assessment summarizes the developments in radiation science in the years leading up to the next millennium. It covers the following: the effects of radiation exposure; levels of radiation exposure; radiological consequences of the Chernobyl accident; sources of radiation exposure including natural exposures, man-made environmental exposures, medical and occupational exposures; radiation associated cancer. This volume includes five Annexes covering: dose assessment methodologies; exposure from natural sources; exposures to the public from man-made sources of radiation and occupational radiation exposures

  15. Testing the integrity of packaging radiation shielding by scanning with radiation source and detector

    International Nuclear Information System (INIS)

    This specification deals with the radiological scanning method of inspection for biological shielding (to be used in transport packaging for gamma emitting sources of radiation), of regular thickness, when the sections are to be checked for integrity and homogeneity; it does not establish the adequacy of design. The shielding materials may be lead, iron, steel, heavy alloy (tungsten), and depleted uranium. (author)

  16. Regulatory control of radiation sources and radioactive materials in Ireland

    International Nuclear Information System (INIS)

    The primary legislation governing safety in uses of ionizing radiation in Ireland is the Radiological Protection Act, 1991. This Act provided for the establishment in 1992 of the Radiological Protection Institute of Ireland, and gives the Institute the functions and powers which enable it to be the regulatory body for all matters relating to ionizing radiation. A Ministerial Order made under the Act in 2000 consolidates previous regulations and, in particular, provides for the implementation in Irish law of the 1996 European Union Directive which lays down basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiation. Under the legislation, the custody, use and a number of other activities involving radioactive substances and irradiating apparatus require a licence issued by the Institute. Currently some 1260 licences are in force. Of these, some 850 are in respect of irradiating apparatus only and are issued principally to dentists and veterinary surgeons. The remaining licences involve sealed radiation sources and/or unsealed radioactive substances used in medicine, industry or education. A schedule attached to each licence fully lists the sealed sources to which the licence applies, and also the quantities of radioactive substances which may be acquired or held under the licence. It is an offence to dispose of, or otherwise relinquish possession of, any licensable material other than in accordance with terms and conditions of the licence. Disused sources are returned to the original supplier or, where this is not possible, stored under licence by the licensee who used them. Enforcement of the licensing provisions relies primarily on the programme of inspection of licensees, carried out by the Institute's inspectors. The Institute's Regulatory Service has a complement of four inspectors, one of whom is the Manager of the Service. The Manager reports to one of the Institute's Principal

  17. Helium Reionization Simulations. I. Modeling Quasars as Radiation Sources

    Science.gov (United States)

    La Plante, Paul; Trac, Hy

    2016-09-01

    We introduce a new project to understand helium reionization using fully coupled N-body, hydrodynamics, and radiative transfer simulations. This project aims to capture correctly the thermal history of the intergalactic medium as a result of reionization and make predictions about the Lyα forest and baryon temperature–density relation. The dominant sources of radiation for this transition are quasars, so modeling the source population accurately is very important for making reliable predictions. In this first paper, we present a new method for populating dark matter halos with quasars. Our set of quasar models includes two different light curves, a lightbulb (simple on/off) and symmetric exponential model, and luminosity-dependent quasar lifetimes. Our method self-consistently reproduces an input quasar luminosity function given a halo catalog from an N-body simulation, and propagates quasars through the merger history of halo hosts. After calibrating quasar clustering using measurements from the Baryon Oscillation Spectroscopic Survey, we find that the characteristic mass of quasar hosts is {M}h∼ 2.5× {10}12 {h}-1 {M}ȯ for the lightbulb model, and {M}h∼ 2.3× {10}12 {h}-1 {M}ȯ for the exponential model. In the latter model, the peak quasar luminosity for a given halo mass is larger than that in the former, typically by a factor of 1.5–2. The effective lifetime for quasars in the lightbulb model is 59 Myr, and in the exponential case, the effective time constant is about 15 Myr. We include semi-analytic calculations of helium reionization, and discuss how to include these quasars as sources of ionizing radiation for full hydrodynamics with radiative transfer simulations in order to study helium reionization.

  18. Helium Reionization Simulations. I. Modeling Quasars as Radiation Sources

    Science.gov (United States)

    La Plante, Paul; Trac, Hy

    2016-09-01

    We introduce a new project to understand helium reionization using fully coupled N-body, hydrodynamics, and radiative transfer simulations. This project aims to capture correctly the thermal history of the intergalactic medium as a result of reionization and make predictions about the Lyα forest and baryon temperature-density relation. The dominant sources of radiation for this transition are quasars, so modeling the source population accurately is very important for making reliable predictions. In this first paper, we present a new method for populating dark matter halos with quasars. Our set of quasar models includes two different light curves, a lightbulb (simple on/off) and symmetric exponential model, and luminosity-dependent quasar lifetimes. Our method self-consistently reproduces an input quasar luminosity function given a halo catalog from an N-body simulation, and propagates quasars through the merger history of halo hosts. After calibrating quasar clustering using measurements from the Baryon Oscillation Spectroscopic Survey, we find that the characteristic mass of quasar hosts is {M}h˜ 2.5× {10}12 {h}-1 {M}⊙ for the lightbulb model, and {M}h˜ 2.3× {10}12 {h}-1 {M}⊙ for the exponential model. In the latter model, the peak quasar luminosity for a given halo mass is larger than that in the former, typically by a factor of 1.5-2. The effective lifetime for quasars in the lightbulb model is 59 Myr, and in the exponential case, the effective time constant is about 15 Myr. We include semi-analytic calculations of helium reionization, and discuss how to include these quasars as sources of ionizing radiation for full hydrodynamics with radiative transfer simulations in order to study helium reionization.

  19. Auroral kilometric radiation source characteristics using ray tracing techniques

    Science.gov (United States)

    Schreiber, R.; Santolik, O.; Parrot, M.; Lefeuvre, F.; Hanasz, J.; Brittnacher, M.; Parks, G.

    2002-11-01

    3-D ray tracing to the presumed auroral kilometric radiation (AKR) source region has been performed using the input data from wave distribution function (WDF) based on the AKR waveforms recorded on board the Interball 2 satellite by the French wave experiment MEMO. Both the direction of the WDF maximum and the WDF form and angular size have been taken into account. Two instances of AKR emissions were observed on 28 January 1997 at 2037 and 2107 UT. Rays traced in R-X mode out of the s/c point toward two different active regions on the auroral oval (as seen with Polar UV imager after projection of the source region along the magnetic field lines down to the ionosphere level). Source region apparent angular sizes based on WDF are compatible with sizes estimated from signal modulation produced by electric antenna system rotation.

  20. Characterization of the radiation background at the Spallation Neutron Source

    Science.gov (United States)

    DiJulio, Douglas D.; Cherkashyna, Nataliia; Scherzinger, Julius; Khaplanov, Anton; Pfeiffer, Dorothea; Cooper-Jensen, Carsten P.; Fissum, Kevin G.; Kanaki, Kalliopi; Kirstein, Oliver; Ehlers, Georg; Gallmeier, Franz X.; Hornbach, Donald E.; Iverson, Erik B.; Newby, Robert J.; Hall-Wilton, Richard J.; Bentley, Phillip M.

    2016-09-01

    We present a survey of the radiation background at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, TN, USA during routine daily operation. A broad range of detectors was used to characterize primarily the neutron and photon fields throughout the facility. These include a WENDI-2 extended range dosimeter, a thermoscientific NRD, an Arktis 4He detector, and a standard NaI photon detector. The information gathered from the detectors was used to map out the neutron dose rates throughout the facility and also the neutron dose rate and flux profiles of several different beamlines. The survey provides detailed information useful for developing future shielding concepts at spallation neutron sources, such as the European Spallation Source (ESS), currently under construction in Lund, Sweden.

  1. Inner radiation belt source of helium and heavy hydrogen isotopes

    Science.gov (United States)

    Leonov, A. A.; Galper, A. M.; Koldashov, S. V.; Mikhailov, V. V.; Casolino, M.; Picozza, P.; Sparvoli, R.

    Nuclear interactions between inner zone protons and atoms in the upper atmosphere provide the main source of energetic H and He isotopes nuclei in the radiation belt. This paper reports on the specified calculations of these isotope intensities using various inner zone proton intensity models (AP-8 and SAMPEX/PET PSB97), the atmosphere drift-averaged composition and density model MSIS-90, and cross-sections of the interaction processes from the GNASH nuclear model code. To calculate drift-averaged densities and energy losses of secondaries, the particles were tracked in the geomagnetic field (modelled through IGRF-95) by integrating numerically the equation of the motion. The calculations take into account the kinematics of nuclear interactions along the whole trajectory of trapped proton. The comparison with new data obtained from the experiments on board RESURS-04 and MITA satellites and with data from SAMPEX and CRRES satellites taken during different phases of solar activity shows that the upper atmosphere is a sufficient source for inner zone helium and heavy hydrogen isotopes. The calculation results are energy spectra and angular distributions of light nuclear isotopes in the inner radiation belt that may be used to develop helium inner radiation belt model and to evaluate their contribution to SEU (single event upset) rates.

  2. Health risk assessment of jobs involving ionizing radiation sources

    Directory of Open Access Journals (Sweden)

    Spasojević-Tišma Vera D.

    2011-01-01

    Full Text Available The study included 75 subjects exposed to low doses of external ionizing radiation and 25 subjects from the control group, all male. The first group (A consisted of 25 subjects employed in the production of technetium, with an average job experience of 15 years. The second group (B consisted of 25 subjects exposed to ionizing radiation from enclosed sources, working in jobs involving the control of X-ray devices and americium smoke detectors, their average work experience being 18.5 years. The third group (C consisted of 25 subjects involved in the decontamination of the terrain at Borovac from radioactive rounds with depleted uranium left over after the NATO bombing of Serbia in 1999, their average job experience being 18.5 years. The control group (K consisted of 25 subjects who have not been in contact with sources of ionizing radiation and who hold administrative positions. Frequencies of chromosome aberrations were determined in lymphocytes of peripheral blood and compared to the control group. The average annual absorbed dose determined by thermoluminescent dosimeters for all three groups did not exceed 2 mSv. In the present study, the largest number of observed changes are acentric fragments and chromosome breaks. The highest occupational risk appears to involve subjects working in manufacturing of the radio-isotope technetium.

  3. An ultrashort pulse ultra-violet radiation undulator source driven by a laser plasma wakefield accelerator

    OpenAIRE

    Anania, M.P.; Brunetti, E; Wiggins, S M; Grant, D W; Welsh, G. H.; Issac, R.C.; Cipiccia, S.; Shanks, R. P.; Manahan, G. G.; Aniculaesei, C.; van der Geer, S. B.; De Loos, M.J.; Poole, M.W.; Shepherd, B. J. A.; Clarke, J A

    2014-01-01

    Narrow band undulator radiation tuneable over the wavelength range of 150–260 nm has been produced by short electron bunches from a 2 mm long laser plasma wakefield accelerator based on a 20 TW femtosecond laser system. The number of photons measured is up to 9 × 106 per shot for a 100 period undulator, with a mean peak brilliance of 1 × 1018 photons/s/mrad2/mm2/0.1% bandwidth. Simulations estimate that the driving electron bunch r.m.s. duration is as short as 3 fs when the electron beam has ...

  4. High-power liquid-lithium target prototype for accelerator-based boron neutron capture therapy.

    Science.gov (United States)

    Halfon, S; Paul, M; Arenshtam, A; Berkovits, D; Bisyakoev, M; Eliyahu, I; Feinberg, G; Hazenshprung, N; Kijel, D; Nagler, A; Silverman, I

    2011-12-01

    A prototype of a compact Liquid-Lithium Target (LiLiT), which will possibly constitute an accelerator-based intense neutron source for Boron Neutron Capture Therapy (BNCT) in hospitals, was built. The LiLiT setup is presently being commissioned at Soreq Nuclear Research Center (SNRC). The liquid-lithium target will produce neutrons through the (7)Li(p,n)(7)Be reaction and it will overcome the major problem of removing the thermal power generated using a high-intensity proton beam (>10 kW), necessary for sufficient neutron flux. In off-line circulation tests, the liquid-lithium loop generated a stable lithium jet at high velocity, on a concave supporting wall; the concept will first be tested using a high-power electron beam impinging on the lithium jet. High intensity proton beam irradiation (1.91-2.5 MeV, 2-4 mA) will take place at Soreq Applied Research Accelerator Facility (SARAF) superconducting linear accelerator currently in construction at SNRC. Radiological risks due to the (7)Be produced in the reaction were studied and will be handled through a proper design, including a cold trap and appropriate shielding. A moderator/reflector assembly is planned according to a Monte Carlo simulation, to create a neutron spectrum and intensity maximally effective to the treatment and to reduce prompt gamma radiation dose risks.

  5. Radiation damage of the ILC positron source target

    Energy Technology Data Exchange (ETDEWEB)

    Ushakov, A.; Riemann, S.

    2007-11-15

    The radiation damage of the positron source target for the International Linear Collider (ILC) has been studied. The displacement damage in target material due to multi-MeV photons has been calculated by combining FLUKA simulations for secondary particle production, SPECTER data for neutron displacement cross-sections and the Lindhard model for estimations of displacement damage by ions. The radiation damage of a stationary Ti6Al4V target in units of displacements per atom (dpa) has been estimated for photons from an undulator with strength 0.92 and period 1.15 cm. The calculated damage is 7 dpa. Approximately 12.5% of displacement damage result from neutrons. (orig.)

  6. Magnetic mirror cavities as terahertz radiation sources and a means of quantifying radiation friction

    Energy Technology Data Exchange (ETDEWEB)

    Holkundkar, Amol R., E-mail: amol.holkundkar@pilani.bits-pilani.ac.in, E-mail: amol.holkundkar@gmail.com [Department of Physics, Birla Institute of Technology and Science, Pilani, Rajasthan 333031 (India); Harvey, Chris, E-mail: cnharvey@physics.org [School of Mathematics and Physics, Queen' s University Belfast, Belfast, Northern Ireland (United Kingdom)

    2014-10-15

    We propose a radiation source based on a magnetic mirror cavity. Relativistic electrons are simulated entering the cavity and their trajectories and resulting emission spectra are calculated. The uniformity of the particle orbits is found to result in a frequency comb in terahertz range, the precise energies of which are tunable by varying the electron's γ-factor. For very high energy particles, radiation friction causes the spectral harmonics to broaden and we suggest this as a possible way to verify competing classical equations of motion.

  7. Magnetic mirror cavities as THz radiation sources and a means of quantifying radiation friction

    CERN Document Server

    Holkundkar, Amol R

    2014-01-01

    We propose a radiation source based on a magnetic mirror cavity. Relativistic electrons are simulated entering the cavity and their trajectories and resulting emission spectra are calculated. The uniformity of the particle orbits is found to result in a frequency comb in terahertz range, the precise energies of which are tuneable by varying the electron's $\\gamma$-factor. For very high energy particles radiation friction causes the spectral harmonics to broaden and we suggest this as a possible way to verify competing classical equations of motion.

  8. National system of notification, authorization and inspection for the control of radiation sources in Ghana

    International Nuclear Information System (INIS)

    The Radiation Protection Board (RPB) was established in 1993 in Ghana as the regulatory authority for radiation protection and safety of radiation sources; its functions are prescribed in the 1993 national radiation protection regulation. The report describes how the country's radiation protection and safety infrastructure have been established, including the RPB's organizational structure, with reference in particular to the main activities carried out by both the Regulatory Control Department and the Radiation and Waste Safety Department. It also briefly mentions the existing RPB human resources; the national system of notification, authorization and inspection of radiation sources; the inventory of radiation sources; and the management of disused radiation sources. Finally, the report identifies the two main problem areas regarding the regulatory control of radiation sources in the country. (author)

  9. Laser sources in dentistry and radiation safety regulations

    Science.gov (United States)

    De Luca, D.; Gaeta, G. M.; Lepore, M.

    2007-02-01

    Nowadays laser sources are largely adopted in dentistry due to their unique properties making them good candidates to substitute traditional scalpel and conventional diamond bur in the surgery of the soft and hard oral tissue, respectively. The large use of laser sources outside the research laboratories without the need of highly specialized personnel can ask for a widespread knowledge of safety issues related to this kind of equipment. The main hazard of accidental exposures regards eyes injury but increasing the power of the laser beam also skin can be involved. Safety legislations in Europe and U.S.A. take into account non ionizing radiations and laser radiation for the hazards for the health deriving from physical agents. Laser safety standards introduce 3 useful parameters for hazard characterization: "Accessible Emission Limit" (AEL), "Maximum Permissible Exposure" (MPE) and "Nominal Ocular Hazard Distance" (NOHD). We measured the MPE and NOHD for Er:YAG and other laser sources currently adopted in dentistry and we compared our results with data elaborated from standards in order to single out safe and comfortable working conditions. In fact an experimental assessment of the hazard parameters and the comparison with those of reference from safety standards turns out to be useful in order to estimate the residual hazard that can be still present after applying all the engineering protection and administrative rules.

  10. Manufacture of 60Co source irradiation facility and measurement of radiation filed

    International Nuclear Information System (INIS)

    60Co source radiation facility is an important equipment to produce reference radiation filed, according to national standard, the scattered dose rate must be less than 5% of the total dose rate in the reference radiation filed. Scattered radiation contribution and uniformity of reference radiation field are important parameters to describe the radiation performance of 60CO source irradiation device, Monte Carlo method was used to study the scattered radiation and uniformity of the reference radiation filed to provide theoretical basis for the design of 60CO source irradiating device in order to avoid economic losses caused by design mistakes. When 60CO source irradiating device was manufactured, PTW ionization chamber was used to measure the irradiation field. The results showed that the scattered radiation and uniformity of the radiation filed were in good agreement with the simulation results. The radiation performance met the design requirements. (authors)

  11. 76 FR 76327 - Installation of Radiation Alarms for Rooms Housing Neutron Sources

    Science.gov (United States)

    2011-12-07

    ... COMMISSION 10 CFR Part 73 Installation of Radiation Alarms for Rooms Housing Neutron Sources AGENCY: Nuclear... radiation alarms in rooms housing neutron sources. DATES: Submit comments by February 21, 2012. Comments..., Radiation Safety for Research. Mr. Hamawy is concerned about the security of neutron sources. III....

  12. Accelerator Based Neutron Beams for Neutron Capture Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Yanch, Jacquelyn C.

    2003-04-11

    The DOE-funded accelerator BNCT program at the Massachusetts Institute of Technology has resulted in the only operating accelerator-based epithermal neutron beam facility capable of generating significant dose rates in the world. With five separate beamlines and two different epithermal neutron beam assemblies installed, we are currently capable of treating patients with rheumatoid arthritis in less than 15 minutes (knee joints) or 4 minutes (finger joints) or irradiating patients with shallow brain tumors to a healthy tissue dose of 12.6 Gy in 3.6 hours. The accelerator, designed by Newton scientific Incorporated, is located in dedicated laboratory space that MIT renovated specifically for this project. The Laboratory for Accelerator Beam Applications consists of an accelerator room, a control room, a shielded radiation vault, and additional laboratory space nearby. In addition to the design, construction and characterization of the tandem electrostatic accelerator, this program also resulted in other significant accomplishments. Assemblies for generating epithermal neutron beams were designed, constructed and experimentally evaluated using mixed-field dosimetry techniques. Strategies for target construction and target cooling were implemented and tested. We demonstrated that the method of submerged jet impingement using water as the coolant is capable of handling power densities of up to 6 x 10(sup 7) W/m(sup 2) with heat transfer coefficients of 10(sup 6)W/m(sup 2)-K. Experiments with the liquid metal gallium demonstrated its superiority compared with water with little effect on the neutronic properties of the epithermal beam. Monoenergetic proton beams generated using the accelerator were used to evaluate proton RBE as a function of LET and demonstrated a maximum RBE at approximately 30-40 keV/um, a finding consistent with results published by other researchers. We also developed an experimental approach to biological intercomparison of epithermal beams and

  13. Measurement of parameters in Indus-2 synchrotron radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Ghodke, A. D.; Husain, Riyasat; Kumar, Pradeep; Yadav, Surendra; Puntambekar, T. A. [Raja Ramanna Centre for Advanced Technology, 452013, Indore (India)

    2012-10-15

    The paper presents the measurement of optics parameters in Indus-2 synchrotron radiation source, which include betatron tune, beta function, dispersion function, natural chromaticity, corrected chromaticity, central RF frequency, momentum compaction factor, and linear betatron coupling. Two methods were used for beta function measurement; a conventional quadrupole scan method and a method using the fitting of the orbit response matrix. A robust Levenberg-Marquardt algorithm was used for nonlinear least square fitting of the orbit response matrix. In this paper, detailed methods for the parameter measurements are described. The measured results are discussed and compared with the theoretical values obtained using accelerator simulation code Accelerator Toolbox in MATLAB.

  14. AREAL test facility for advanced accelerator and radiation source concepts

    Science.gov (United States)

    Tsakanov, V. M.; Amatuni, G. A.; Amirkhanyan, Z. G.; Aslyan, L. V.; Avagyan, V. Sh.; Danielyan, V. A.; Davtyan, H. D.; Dekhtiarov, V. S.; Gevorgyan, K. L.; Ghazaryan, N. G.; Grigoryan, B. A.; Grigoryan, A. H.; Hakobyan, L. S.; Haroutiunian, S. G.; Ivanyan, M. I.; Khachatryan, V. G.; Laziev, E. M.; Manukyan, P. S.; Margaryan, I. N.; Markosyan, T. M.; Martirosyan, N. V.; Mehrabyan, Sh. A.; Mkrtchyan, T. H.; Muradyan, L. Kh.; Nikogosyan, G. H.; Petrosyan, V. H.; Sahakyan, V. V.; Sargsyan, A. A.; Simonyan, A. S.; Toneyan, H. A.; Tsakanian, A. V.; Vardanyan, T. L.; Vardanyan, A. S.; Yeremyan, A. S.; Zakaryan, S. V.; Zanyan, G. S.

    2016-09-01

    Advanced Research Electron Accelerator Laboratory (AREAL) is a 50 MeV electron linear accelerator project with a laser driven RF gun being constructed at the CANDLE Synchrotron Research Institute. In addition to applications in life and materials sciences, the project aims as a test facility for advanced accelerator and radiation source concepts. In this paper, the AREAL RF photoinjector performance, the facility design considerations and its highlights in the fields of free electron laser, the study of new high frequency accelerating structures, the beam microbunching and wakefield acceleration concepts are presented.

  15. Measurement of parameters in Indus-2 synchrotron radiation source.

    Science.gov (United States)

    Ghodke, A D; Husain, Riyasat; Kumar, Pradeep; Yadav, Surendra; Puntambekar, T A

    2012-10-01

    The paper presents the measurement of optics parameters in Indus-2 synchrotron radiation source, which include betatron tune, beta function, dispersion function, natural chromaticity, corrected chromaticity, central RF frequency, momentum compaction factor, and linear betatron coupling. Two methods were used for beta function measurement; a conventional quadrupole scan method and a method using the fitting of the orbit response matrix. A robust Levenberg-Marquardt algorithm was used for nonlinear least square fitting of the orbit response matrix. In this paper, detailed methods for the parameter measurements are described. The measured results are discussed and compared with the theoretical values obtained using accelerator simulation code Accelerator Toolbox in MATLAB.

  16. Design of an electron gun for terahertz radiation source

    International Nuclear Information System (INIS)

    An EC-ITC (External-Cathode Independently Tunable Cells) RF gun was employed with the aim of obtaining short-pulse bunches with high peak current for a terahertz radiation source. A gridded DC gun plays a key role as the external injecting electron source of the ITC RF gun, the performance of which determines the beam quality in the injector and transport line. In order to make the beam well compressed in the ITC RF gun, the energy of the electrons acquired from the gridded DC gun should be 15 keV at most. A proper structure of the gridded gun with double-anode is shown to overcome the strong space-charge force on the cathode, which is able to generate 6 μs beam with 4.5 A current successfully. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Reactor - and accelerator-based filtered beams

    International Nuclear Information System (INIS)

    The neutrons produced in high flux nuclear reactors and in accelerator, induced fission and spallation reactions, represent the most intense sources of neutrons available for research. However, the neutrons from these sources are not monoenergetic, covering the broad range extending from 10-3 eV up to 107 eV or so. In order to make quantitative measurements of the effects of neutrons and their dependence on neutron energy it is desirable to have mono-energetic neutron sources. The paper describes briefly methods of obtaining mono-energetic neutrons and different methods of filtration. This is followed by more detailed discussion of neutron window filters and a summary of the filtered beam facilities using this technique. The review concludes with a discussion of the main applications of filtered beams and their present and future importance

  19. Photoluminescence and Photonics: from miniaturised light sources to radiation detectors

    International Nuclear Information System (INIS)

    Photonics is the science of the harnessing of light. Photonics encompasses the generation of light, the detection of light, the management of light through guidance, manipulation, and amplification. Luminescence phenomena are widely used in solid state light sources and radiation detectors based on point defects in insulators. Among them, 2 ed F3+ aggregate colour centres are induced in lithium fluoride (LiF) by various kinds of ionizing radiation and are laser active in the visible spectral region. They have been studied and successfully used at Frascati ENEA Research Centre for realizing prototypes of both miniaturized light sources, in the form of waveguides and vertical optical micro cavities for integrated optics, and of novel X-ray imaging detectors, based on the optical reading of photoluminescence of the locally induced defects. The highest intrinsic spatial resolution on a wide field of view and their versatility, achieved by the growth of LiF thin films by thermal evaporation, allow using such detectors in the frameworks of nano photonics, life science and energy. Recently, they have been also used in the advanced diagnostics of proton beams, with promising results in imaging and dosimetry based on photoluminescence

  20. Calculating the background radiation in the vicinity of the beam catchers of the ELBE radiation source

    International Nuclear Information System (INIS)

    The ELBE radiation sources comprises beam catchers in the experimenting sites which absorb the primary electron beam as well as the generated secondary radiation. The beam catcher consists of an ultrapure graphite absorber enclosed in a water-cooled stainless steel shell. Background radiation is shielded by iron, lead and heavy concrete. The beam parameters and the position of the beam catchers differ between experimenting sites. In order to determine the dose dependence of photon and neutron fluence and the dose equivalent at the cooling shell of the beam catcher, simulations were carried out using the FLUKA code. Radiation energies of 20 MeV and 50 MeV and electron fluxes of 1 mA were considered. The spatial and energetic distributions of the dose rate equivalent provide a basis for dimensioning of the radiation shields. The calculated distributions of the energy dose rate in the beam catcher serve as a basis for assessing thermal loads on materials and for designing the cooling system. (orig.)

  1. Insurance of Radioisotopes and Ionizing Radiation Sources in France

    International Nuclear Information System (INIS)

    Since the early sixties, Assuratome has amassed quite a long experience in the insurance of radioisotopes and more generally of ionising radiation sources when they are used transported or stored outside a nuclear installation. Aware of the specific dangers of such devices, and having no experience in this domain French insurers were looking for a pragmatic solution which would permit to continue to provide cover for users or fabricants of small radioactive sources and in the meantime to keep a rigorous control on the claims and on the loss ratio which would be achieved over the years. Hence the decision was taken by the French Insurance market to entrust the French Nuclear Insurance Pool, Assuratome, as the recommended body for delivering specific 'nuclear policies' as an expert for this category of business. The next step was to make sure that the 'conventional policies' would not provide the same cover. Therefore, an appropriate exclusion clause was introduced in all the general conditions of the TPL Policies of the conventional market and consequently in the majority, if not all, the reinsurance treaties. Besides the obvious advantage resulting in the management of this category of business in a centralised body, a major benefit of this situation is based on the strict control by the insurer of the compulsory authorisation delivered by the authorities to the owner of the radioactive source. Unofficial sources having in principal no insurance possibilities in France their use would be virtually impossible.(author)

  2. Design of a photoneutron source for time-of-flight experiments at the radiation source Elbe

    International Nuclear Information System (INIS)

    The new radiation source ELBE uses the high brilliance electron beam from a superconducting LINAC to produce various secondary beams. Electron beam intensities of up to 1 mA at energies between 12 MeV and 40 MeV can be delivered with a wide variability in the electron pulse structure. The small emittance of the electron beam permits the irradiation of very small volumes. These main beam parameters led to the idea to convert the intense picosecond electron pulses into sub-ns neutron pulses by stopping the electrons in a heavy (high atomic number) radiator and to produce neutrons by Bremsstrahlung photons through (γ,n)-reactions. In order to enable the measurements of energy resolved neutron cross sections with a time-of-flight arrangement with a short flight path of only a few meters, it is necessary to keep the volume of the radiator for neutron production as small as possible to avoid multiple scattering of the emerging neutrons which would broaden the neutron pulses. The energy deposition of the electron beam in the small neutron radiator is that high that any solid material would melt. Therefore, the neutron radiator consists of liquid lead flowing through a channel of 11.2*11.2 mm2 cross section. From the thermal and mechanical point of view molybdenum turned out to be the most suited channel wall (thickness 0.5 mm) material. Depending on the electron energy and current up to 20 kW power will be deposited into a radiator volume of 3 cm3. This heating power is removed through the heat exchanger in the liquid lead circuit. Typical flow velocities of the lead are in the range of 2 m/s in the radiator section. Particle transport calculations were carried out using the Monte Carlo codes MCNP and FLUKA. These calculations predict a neutron source strength of 7.88 1012 and 2.67 1013 n/s for electron energies between 20 and 40 MeV. At the measuring place 362 cm away from the radiator, neutron fluxes of 1.7 107 n/cm2*s) will be obtained. The mentioned time

  3. Accelerator-based studies of intercombination transitions

    International Nuclear Information System (INIS)

    Intercombination transitions in multiply-charged few-electron ions have been studied for a number of years now by a number of methods, including beam-foil spectroscopy. Only very recently it has been realized that the intrinsic properties of the beam-foil light source, in particular the time resolution, offer means to single out and measure such transitions from the multiline spectra of many-electron ions where the exploitation of other light sources has been less successful. Wavelengths and transition rates of these lines provide both a test of many-electron atomic theory and tools for plasma diagnostics. As examples, data on Mg-, Al- and Si-like ions of elements Ti-Zn are presented and compared with tokamak, laser-produced plasma and solar flare data. It turns out that the level of adequacy reached by the various theoretical approaches for predictions of wavelengths and transition probabilities in the individual isoelectronic sequences is very different. However, even calculational schemes which are successful for one sequence are much worse for others. The variety of isoelectronic sequences and the ranges of ionic charge for each of the sequences which are accessible at typical heavy-ion accelerator laboratories are outlined in order to encourage the use of existing facilities for this type of spectroscopy. (orig.)

  4. Crystal Undulator As A Novel Compact Source Of Radiation

    CERN Document Server

    Bellucci, S; Biryukov, V M; Britvich, G I; Chesnokov, Yu A; Giannini, G; Guidi, V; Ivanov, Y M; Kotov, V I; Maisheev, V A; Malagu, C; Martinelli, G; Petrunin, A A; Pikalov, V A; Skorobogatov, V V; Stefancich, M; Tombolini, F; Vincenzi, D; Chesnokov, Yu. A.; Ivanov, Yu. M.

    2004-01-01

    A crystalline undulator (CU) with periodically deformed crystallographic planes is capable of deflecting charged particles with the same strength as an equivalent magnetic field of 1000 T and could provide quite a short period L in the sub-millimeter range. We present an idea for creation of a CU and report its first realization. One face of a silicon crystal was given periodic micro-scratches (grooves), with a period of 1 mm, by means of a diamond blade. The X-ray tests of the crystal deformation have shown that a sinusoidal-like shape of crystalline planes goes through the bulk of the crystal. This opens up the possibility for experiments with high-energy particles channeled in CU, a novel compact source of radiation. The first experiment on photon emission in CU has been started at LNF with 800 MeV positrons aiming to produce 50 keV undulator photons.

  5. ENHANCEMENT OF HYGIENIC REQUIREMENTS TO THE LIMITATION OF THE POPULATION EXPOSURE FROM NATURAL RADIATION SOURCES

    OpenAIRE

    I. K. Romanovich; I. P. Stamat

    2016-01-01

    The article addresses the issues of regulation system development for the population radiation protection due to the exposurefrom natural radiation. Justification of necessity of separate requirements introduction for population radiation protection from exposure due to natural and artificial radiation sources is done.

  6. Accelerator based techniques for aerosol analysis

    International Nuclear Information System (INIS)

    At the 3 MV Tandetron accelerator of the LABEC laboratory of INFN (Florence, Italy) an external beam facility is fully dedicated to PIXE-PIGE measurements of elemental composition of atmospheric aerosols. Examples regarding recent monitoring campaigns, performed in urban and remote areas, both on a daily basis and with high time resolution, as well as with size selection, will be presented. It will be evidenced how PIXE can provide unique information in aerosol studies or can play a complementary role to traditional chemical analysis. Finally a short presentation of 14C analysis of the atmospheric aerosol by Accelerator Mass Spectrometry (AMS) for the evaluation of the contributions from either fossil fuel combustion or modern sources (wood burning, biogenic activity) will be given. (author)

  7. Radiation protection and safety of radiation sources international basic safety standards

    CERN Document Server

    International Atomic Energy Agency. Vienna

    2014-01-01

    The Board of Governors of the IAEA first approved Basic Safety Standards in June 1962; they were published by the IAEA as IAEA Safety Series No. 9. A revised edition was issued in 1967. A third revision was published by the IAEA as the 1982 Edition of IAEA Safety Series No. 9 ; this edition was jointly sponsored by the IAEA, ILO, OECD/NEA and the WHO. The next edition was International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources, published by the IAEA as IAEA Safety Series No. 115 in February 1996, and jointly sponsored by the FAO, IAEA, ILO, OECD/NEA, PAHO and the WHO.

  8. Acoustic radiation field of the truncated parametric source generated by a piston radiator model and experiment

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiaoliang; ZHU Zhemin; DU Gonghuan; TANG Haiqing; LI Shui; MIAO Rongxing

    2001-01-01

    A theoretical model is presented to describe the parametric acoustic field generated by a piston radiator. In the model, the high-frequency primary wave interaction region that is truncated by a low-pass acoustic filter can be viewed as a cylindrical source within the Rayleigh distance of the piston. When the radius of the piston is much smaller than the length of the parametric region, this model is reduced to the Berketey's End-Fire Line Array model. Comparison between numerical calculations and experimental measurement show that the generated parametric sound field (especially near the axis) agrees well with the experiment results.

  9. In vitro unsealed sources. Radiation protection: research sector

    International Nuclear Information System (INIS)

    This sheet concerns the use of unsealed radioactive sources, and is addressed at experts in radiation protection (PCR), occupational doctors, employers, and researchers and technicians using these techniques. After a brief indication of practice types and of personnel concerned by this risk, the sheet indicates the operational processes, the hazards and risks. It describes how to assess the risk and to determine exposure levels (elements for risk assessment, delimitation of controlled and monitored areas, workstation studies and personnel classification, choice of the dose monitoring method), presents the risk management strategy (risk reduction, technical measures regarding the installation, the instrumentation, and sources, management of wastes and of effluents contaminated by radionuclides, measures regarding the personnel), presents various aspects of medical monitoring (strengthened monitoring, examinations, case of subcontracting companies, case of pregnant or breast feeding women, medical file and post-occupational monitoring). It addresses what must be done in case of incident or dysfunction (premise or equipment contamination, contamination of a person, administrative aspects), mentions the associated biological, chemical, physical and psychological risks. It describes how risk management is to be assessed. A sheet is provided in appendix which describes the general approach to a workstation study

  10. Radiation of complex and noisy sources within enclosures

    Science.gov (United States)

    Gradoni, Gabriele; Creagh, Stephen; Tanner, Gregor

    Predicting the radiation of complex electromagnetic sources inside semi-open cavities and resonators with arbitrary geometry is a challenging topic both for physics and for engineering. We have exploited a Perron-Frobenius operator to propagate field-field correlation functions of complex and extended sources in free-space. The formula is based on a phase-space picture of the electromagnetic field, using the Wigner distribution function, and naturally captures evanescent as well as diffracted waves. This approach can be extended to study the propagation of correlation functions within cavities, with the ray-dynamical map given by the geometry of the cord connecting a point of the boundary to another. While ray methods provide an efficient way to predict average values of the correlation matrix elements, the use of random matrix theory approaches allows efficient characterisation of statistical fluctuations around these averages. Universal relations are derived and tested in the presence of dissipation for quantum maps and billiard systems. The use of this formalism is discussed in the contexts of open systems with surface roughness. The theory and achieved results are of interest in the simulation of next-generation of wireless communications. Work supported by the UK Engineering and Physical Sciences Research Council.

  11. Indus-2 Synchrotron Radiation Source: current status and utilization

    International Nuclear Information System (INIS)

    Indus Synchrotron Radiation complex at Raja Ramanna Centre for Advanced Technology at Indore, India houses two synchrotron radiation sources: Indus-1 and Indus-2. Indus-1 is a 450 MeV source emitting in VUV/ soft x-ray region and operating at 100 mA since 1999. Indus-2 is designed for 2.5 GeV, 300 mA operation and is operating at 2 GeV and 100 mA since March 2010 in 24x7 mode and a beam lifetime of about 22 hrs has been achieved. Operation at 2.5 GeV and 100 mA has recently been demonstrated with the addition of in-house developed solid state RF amplifiers. Indus-2 can accommodate 21 bending magnet (BM) and 5 insertion device (ID) beamlines. Sixteen BM beamlines have been planned and six BM beamlines namely i) Angle Dispersive XRD ii) Energy dispersive XRD iii) Energy dispersive EXAFS iv) Soft and deep x-ray lithography v) X-ray fluorescence micro-probe and vi) X-ray photoelectron spectroscopy beamlines have been commissioned. These are being used by researchers from different universities, national institutes and laboratories for carrying out several investigations. Two more beamlines namely 'Grazing incidence x-ray scattering' and 'Protein crystallography' are nearing commissioning. A number of materials research related problems have been investigated using these beamlines and several papers have already been published. Here we will report on the current status of the source, details of the beamlines already operational, beamlines to be commissioned soon and several up-gradation schemes that are being planned. Five IDs consisting of two soft x-ray planar undulators, one superconducting wavelength shifter / wiggler, one APPLE II soft x-ray helical undulator and one hard x-ray undulator will be installed during the next few years. Three new ID based beamli-nes for Atomic and Molecular physics, Angle integrated / Angle resolved PES and Magnetic Circular Dichroism experiments will be commissioned.

  12. LIGHT SOURCE: Design of a new compact THz source based on Smith-Purcell radiation

    Science.gov (United States)

    Dai, Dong-Dong; Bei, Hua; Dai, Zhi-Min

    2009-06-01

    In recent years, people are dedicated to the research work of finding compact THz sources with high emission power. Smith-Purcell radiation is qualified for the possibility of coherent enhancement due to the effect of FEL mechanism. The compact experiment device is expected to produce hundreds mW level THz ray. The electron beam with good quality is provided under the optimized design of the electron gun. Besides, the grating is designed as an oscillator without any external feedbacks. While the beam passes through the grating surface, the beam bunching will be strong and the second harmonics enhancement will be evident, as is seen from the simulation results.

  13. Study on establishment of national information data base for the radiation sources in China

    International Nuclear Information System (INIS)

    China is a big developing country with large use of radioactive sources and nuclear technology. There are great number and different types of radioactive sources and radiation emitting apparatus. As a developing country, China still has a long way to go compared with advanced developed countries in the fields of radiation safety management and related technology. Up to now, some basic information are not clear, such as exact number, type, radiation character, purpose of using radiation sources and the owners of the radioactive sources and radiation emitting apparatus. And also, the information system and related data base has not been established yet. Another problem is that the Chinese experts do not fully master the incidents and accidents happened worldwide, so that the effective experience feedback can not be implemented. From preliminary survey there are 30000 - 50000 radioactive sources in China. Some people died or injured by radioactive accidents in the application of radioactive sources and nuclear technology in China. And some accidents such as loss control of radioactive sources caused radioactive contamination dispersion so that the radioactive materials contaminated environment in certain areas in the past. The Chinese government has paid great attention to the radiation safety in the development of radioactive sources and nuclear technology utilization. The radiation safety management and control on radioactive sources and nuclear technology utilization will be strengthened. In order to ensure the radiation safety and master the exact number of the radiation sources in China, we should investigate and integrate the basic information of radiation sources, including the spent radiation sources. The paper suggest to establish the information data base of radiation safety management on radioactive sources and nuclear technology utilization in China, based on the analysis of the present situation and problems in China. The paper also discusses the contents

  14. Absolutely connected sets of standard radiation sources for dissemination of the activity unit

    International Nuclear Information System (INIS)

    Sealed gamma sources and plane beta sources to be used as reference standards have been produced in such a way that in connecting measurements certain corrections have been avoided (e.g. self-absorption) or can be eliminated (e.g. backscattering). The production of the radiation sources and the technique of absolute connection to the primary standard of the activity unit are described for one set of gamma and beta radiation sources each, and a survey of the standard radiation source sets available is given, considering nuclides, type of source, activity and measuring accuracy. (author)

  15. Addition Laws for Intensities of Radiation Emerging from Scattering Atmospheres Containing Energy Sources

    Science.gov (United States)

    Nikoghossian, A. G.; Kapanadze, N. G.

    2016-03-01

    A group theoretical approach is developed for solving astrophysical radiative transfer problems described in a previous series of papers. Addition laws for observed radiative intensities are derived for the case in which atmospheres not only absorb and scatter radiation incident on them, but radiate themselves because of energy sources contained within them. As an illustration of the application of these laws, several special radiative transfer problems which we believe are of practical interest are discussed.

  16. Development of quality assurance program for production of sealed radiation source

    CERN Document Server

    Nam, J H; Cho, W K; Han, H S; Hong, S B; Kim, K H; Kim, S D; Lee, Y G; Lim, N J

    2001-01-01

    The quality assurance program for production of sealed radiation sources has been developed to increase the efficiency and safety of production work and to meet the demand of the customers. The quality assurance program are applied to the entire work scope of the production of sealed radiation sources. Every workers related to the production of sealed radiation sources will be required to follow this quality assurance program. It is expected that the sealed radiation source products produced according to this quality assurance program can meet the regulatory requirements, customer's demand and have good competitiveness in the domestic and world markets.

  17. Industrial Uses of Large Radiation Sources. Proceedings of a Conference on the Application of Large Radiation Sources in Industry. Vol. II

    International Nuclear Information System (INIS)

    Energy in the form of ionizing radiation has not yet been accepted by industry for use in large scale manufacturing processes. Among its various applications, such radiation can sometimes be used to obtain a unique product, sometimes to lower the production costs of an existing material. During the past few years considerable research has been carried out on chemical reactions of potential industrial use and already some processes are emerging to form the basis of a radiation chemical industry. More rapidly advancing is the use of radiation for sterilization, where a number of commercial plants are already in operation for the sterilization of surgical goods. The first international scientific meeting on the use of large radiation sources was held in Warsaw in 1959 and was organized by the International Atomic Energy Agency. Recent progress was discussed at the second IAEA conference on the ''Application of Large Radiation Sources in Industry'' in Salzburg in May, 1963. About 250 scientists from many countries attended the meeting to discuss the 40 papers presented. The papers were considered under three headings: I. Research on applications of potential industrial use; II. Radioisotope power sources; III. Experience, operation and economics. Most of the papers were in the first group and involved a wide variety of subjects. These included synthesis of chemical compounds, copolymerization reactions, possible applications of radiation in the textile industry and radiation-induced vulcanization of rubber. Much interest was centred on the papers in the third group as, for the first time, actual operating experience with large radiation sources, integrated into a full-scale manufacturing process, could be evaluated. The Proceedings of the conference are now being published by the Agency as ''Industrial uses of large radiation sources'' (Vols. I and II) in the hope that the information made available to industry in general will help to promote greater use of radiation

  18. Industrial Use of Large Radiation Sources. Proceedings of a Conference on the Application of Large Radiation Sources in Industry. V. I

    International Nuclear Information System (INIS)

    Energy in the form of ionizing radiation has not yet been accepted by industry for use in large scale manufacturing processes. Among its various applications, such radiation can sometimes be used to obtain a unique product, sometimes to lower the production costs of an existing material. During the past few years considerable research has been carried out on chemical reactions of potential industrial use and already some processes are emerging to form the basis of a radiation chemical industry. More rapidly advancing is the use of radiation for sterilization, where a number of commercial plants are already in operation for the sterilization of surgical goods. The first international scientific meeting on the use of large radiation sources was held in Warsaw in 1959 and was organized by the International Atomic Energy Agency. Recent progress was discussed at the second IAEA conference on the ''Application of Large Radiation Sources in Industry'' in Salzburg in May, 1963. About 250 scientists from many countries attended the meeting to discuss the 40 papers presented. The papers were considered under three headings: I. Research on applications of potential industrial use; II. Radioisotope power sources; III. Experience, operation and economics. Most of the papers were in the first group and involved a wide variety of subjects. These included synthesis of chemical compounds, copolymerization reactions, possible applications of radiation in the textile industry and radiation-induce d vulcanization of rubber. Much interest was centred on the papers in the third group as, for the first time, actual operating experience with large radiation sources, integrated into a full-scale manufacturing process, could be evaluated. The Proceedings of the conference are now being published by the Agency as ''Industrial uses of large radiation sources'' (Vols. I and II) in the hope that the information made available to industry in general will help to promote greater use of radiation

  19. Radiation education for high school students by measurement sharing method using radiation sources fabricated from potassium chloride chemicals

    International Nuclear Information System (INIS)

    In the National Institute for Fusion Science, various exercises are practiced for high school students. One of the exercises is an environmental radiation measurement. In the recent exercise we began to use potassium chloride radiation sources that contained the naturally occurring radioisotope potassium-40. In this study, a measurement sharing method was first applied to the measurements. Through the exercise, students understood the existence of natural radiation and radioisotopes around us, and learned the three principles of radiation protection. According to the questionnaire survey conducted after the exercise, it was found that the environmental radiation measurement by the measurement sharing method using potassium chloride radiation sources was favorably received by many high school students. (author)

  20. Novel particle and radiation sources and advanced materials

    Science.gov (United States)

    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.

  1. Residual gas analysis system of synchrotron radiation source Indus-2

    International Nuclear Information System (INIS)

    Indus-2 is a 2.5 GeV e- storage ring dedicated for its application as Synchrotron Radiation Source (SRS) in the X-ray wavelength region. The beam lifetime is expected to be nearly 20 hours at 300 mA beam current with 2.5 GeV energy. The beam lifetime of 2.5 GeV storage ring is mainly dependent on the vacuum in the storage ring and on the species of gas molecules therein. The residual gas analysis provides the information about gas species present in the Indus-2 vacuum envelope. Eleven Residual Gas Analyzers (RGAs) were installed to know about the residual gas species present inside the Indus-2 vacuum system. A short overview of the installed RGA system is given in detail. During Indus-2 operation residual gas analysis is carried out with RGAs at the important locations. RGAs are also used for in-situ leak detection. This paper outlines the present status of Residual Gas Analysis (RGA) System on Indus-2, its performance over the last few years and their application as leak detector in Indus-2. (author)

  2. Disk shaped radiation sources for education purposes made of chemical fertilizer

    International Nuclear Information System (INIS)

    A method for fabricating a disk-shaped radiation source from material containing natural radioisotopes was developed. In this compression and formation method, a certain amount of powdered material is placed in a stainless steel formwork and compressed to form a solid disk. Using this method, educational radiation sources were fabricated using commercially available chemical fertilizers that naturally contain the radionuclide, 40K, which emits either beta or gamma rays, at each disintegration. The compression and formation method was evaluated by inspecting eleven radiation sources thus fabricated. Then the suitability of the fertilizer radiation source as an education aid was evaluated. The results showed that the method could be used to fabricate radiation sources without the need for learning special skills or techniques. It was also found that the potassium fertilizer radiation source could be used to demonstrate that the inverse-square law can be applied to the distance between the radiation source and detector, and that an exponential relationship can be seen between the shielding effectiveness and the total thickness of the shielding materials. It is concluded that a natural fertilizer radiation source is an appropriate aid for demonstrating the characteristics of radiation. (author)

  3. Educational advertising of the public about the use of radiation sources in technology, research and medicine

    International Nuclear Information System (INIS)

    At the latest since Tschernobyl the use of radiation sources and ionizing radiation is due to missing knowledge of the public not affected by popularity but rather by fear. But the question is, whether it would be necessary on the part of the radiation users, not to conceal or mythologise the use, but to emphasize on educational advertising. (orig.)

  4. Radiation protection for the illegal governmental use of radiation sources. A case study

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.

    2000-07-01

    Probably for the first time, illegal governmental uses of radiation sources, including the administrative infrastructure such as special radiation protection regulation, an advisory body etc., have been documented by the evaluation of the documents of the Ministry of State Security in the former German Democratic Republic (East Germany). Over a thousand persons, but also documents, money bills etc. were marked with a wide variety of radionuclides and traced with specially developed detectors. Among the many different nuclides provided regularly from the Rossendorf Research Center near Dresden, in particular {sup 46}Sc was popular. (orig.) [German] 'Regierungskriminalitaet' kann man auch im deutschen Strahlenschutz finden. Anhand neuer Dokumentationen der so genannten Gauckbehoerden, ueber die auch schon fluechtig in der Presse berichtet und spekuliert wurde, lassen sich Einzelheiten ueber die Vorgehensweisen einfallsreicher Stasi-Mitarbeiter, die Stasi-eigene Strahlenschutzverordnung und Strahlenschutz-Kommission usw. rekonstruieren. Ueber 1.000 Personen, aber auch Gegenstaende, Dokumente, Geldscheine etc. wurden markiert, wobei unter einer Vielzahl der regelmaessig aus Rossendorf gelieferten Nukliden {sup 46}Sc besonders gern eingesetzt sowie in Dresden spezielle Nachweisgeraete entwickelt wurden. (orig.)

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

    Science.gov (United States)

    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.

  6. Tetrode bias power supply for Indus-1, synchrotron radiation source

    International Nuclear Information System (INIS)

    An AC regulator based 7 kV, 3 A high voltage DC power supply is designed, fabricated and tested on dummy load for BEL make Tetrode type 15000CX, used in the high power RF amplifier at 31.613 MHz employed with INDUS-1, Synchrotron Radiation Source (SRS). Various protections features like over voltage, under voltage, over current, phase failure and phase reversal are incorporated in this power supply and presented in this paper. As Tetrode amplifier requires various other power supplies in addition to this bias power supply and they are operated in a particular sequence for its healthy operation, suitable interlock arrangements have been incorporated and also presented in this paper. The reliable operation of protection and interlock features incorporated in this power supply has been checked with dummy load under simulated conditions. Three numbers of series limiting inductors, one in each phase, have been incorporated in this power supply to limit fault currents under unfavourable conditions and there by increasing the overall life of this power supply. It will replace existing 7 kV, 3 A HVDC power supply, which is in operation for more than fifteen years with Indus-1 SRS and is likely to be helpful in reducing the down time of Indus-1 SRS. It has better performance features than the existing power supply. The long term voltage stability better than 0.3 % and output ripple less than 0.3 % have been achieved for this Tetrode bias power supply. This power supply is likely to be integrated with INDUS-1 SRS soon. (author)

  7. A basic radiation-education method using a handy-type cloud chamber and natural radiation sources

    International Nuclear Information System (INIS)

    Nuclear human resources development becomes increasingly important due to the world trend of expanding nuclear energy utilization in this century. At the Nuclear Human Resource Development Center of the Japan Atomic Energy Agency, many kinds of nuclear and radiation education have been conducted consistently and continuously through its half-century history though having several organizational changes. High level education is required for the specialists of nuclear technology including nuclear power plants operators and engineers, while basic knowledge on nuclear energy and, specially, on radiations and radioisotopes should be given to school students and public. Besides lectures on radiation and radioisotopes, some basic experiments are useful to understand what are radiations and radioisotopes. One of such basic experiments is the cloud chamber experiment. It is a great fun and excitement even for small children as one can actually see the radiation tracks by his/her naked eyes at hand. While there are many types of cloud chambers, we have developed a new-type cloud chamber to use for the radiation education and training s. Using the new-type cloud chamber, we have further developed a new method of this experiment so that the participants can more deeply understand the phenomena and the nature of radiation and radioisotopes. In this method, using a radiation source of natural uranium ore and gaseous radiation source containing Rn-220 obtained from thorium-containing material, they not only observe the radiation tracks but also measure the length and count the number of the tracks. Then they can calculate the energy of the radiation (alpha ray) and can estimate the half-life of the radioisotope (Rn-220). This method can be applied for high-school and general university students as well as for the public as a useful and effective method in the radiation education. (Author)

  8. Management of ionizing radiation sources in university, medical and industrial environments

    International Nuclear Information System (INIS)

    This conference treats several subjects relative to the use of radioactive sources. The first session comprises three articles about ionizing sources and regulation. The second session, with three articles, tackles the question of radiation protection in the use of sources in industrial field. The third session, four articles, treats the same question but in the medicine and university media. The fourth session (three articles) is devoted to the organisation of radiation protection in the case of accidents. The fifth session concerns the management of spent sources (three articles). The sixth session studies the radiation protection of sources in Europe. The seventh and final session ends with the part and coordination of actors in radiation protection in the sources management (three articles). (N.C.)

  9. Development of quality assurance procedures for production of sealed radiation source

    CERN Document Server

    Nam, J H; Cho, W K; Han, H S; Hong, S B; Kim, K H; Kim, S D; Lee, Y G; Lim, N J

    2001-01-01

    The quality assurance procedures for sealed radiation sources production using HANARO and RIPF have been developed. The detailed quality assurance procedures are essential to manage the whole work process effectively and ensure the quality of the produced sealed sources. Through applying this quality assurance procedures to the entire production works of the sealed radiation sources, it is expected that the quality of the products, the safety of the works and the satisfaction of the customers will be increased.

  10. Compact THz radiation source based on photocathode RF gun

    Institute of Scientific and Technical Information of China (English)

    URAKAWA; JunJi

    2011-01-01

    Terahertz (THz) science and technology have already become the research highlight at present. In this paper, we put forward a proposal to generate THz radiation at tens of MW peak power. As a result of the ultrafast laser and the high accelerating field of photocathode RF gun, we can generate and accelerate an electron beam to several MeV, of which the bunch length is less than sub-ps. When the short electron bunches are injected into the wiggler, THz radiation based on Coherent Synchrotron Radiation could be achieved with tens of MW peak power. The whole THz FEL facility can be scaled to the size of a tabletop.

  11. Evaluation of the Timepix chip radiation hardness using a {sup 60}Co source

    Energy Technology Data Exchange (ETDEWEB)

    Čarná, Mária; Dučevová, Kateřina; Hejtmánek, Martin, E-mail: hejtmark@fzu.cz; Konček, Ondřej; Marčišovský, Michal

    2013-12-21

    Radiation damage is a widely studied topic for its effects on detectors and supporting electronics in various practical applications. Radiation hardness and stability of the detector properties are critical parameters in applications of semiconductor radiation detectors. The 0.25μm CMOS technology used in fabrication of the Medipix2 and Timepix chips provides high degree of inherent radiation hardness. We present the study of operational, detection and signal processing properties of the irradiated Timepix chip exposed to a high-flux {sup 60}Co source reaching the operational limits of the chip. -- Highlights: • Radiation hardness of pixel detector based on Medipix2 against {sup 60}Co has been performed. • The {sup Co} was used as a radiation source due to its usage in number of practical applications. • Systematic study of γ radiation of various energies on the detector systems is desired.

  12. Dosimetric comparison of linear accelerator-based stereotactic radiosurgery systems

    OpenAIRE

    Sharma S; Kumar Sudhir; Dagaonkar S; Bisht Geetika; Dayanand S; Devi Reena; Deshpande S; Chaudhary S; Bhatt B; Kannan S

    2007-01-01

    Stereotactic radiosurgery (SRS) is a special radiotherapy technique used to irradiate intracranial lesions by 3-D arrangements of narrow photon beams eliminating the needs of invasive surgery. Three different tertiary collimators, namely BrainLab and Radionics circular cones and BrainLab micro multileaf collimator (mMLC), are used for linear accelerator-based SRS systems (X-Knife). Output factor (St), tissue maximum ratio (TMR) and off axis ratio (OAR) of these three SRS systems were measured...

  13. Synchrotron radiation sources- INDUS-1 and INDUS-2

    International Nuclear Information System (INIS)

    The design features of INDUS-1 and INDUS-2 and their radiation characteristics such as variation of flux and brightness with wavelength are discussed. The construction of INDUS-1 and the injector system has reached an advanced stage and the design of INDUS-2 is in a final stage of optimization. The status of the synchrotron radiation facility is discussed briefly. (author). 4 figs., 2 tabs

  14. Proceedings of the specialists' meeting on accelerator-based transmutation

    International Nuclear Information System (INIS)

    The meeting was organised under the auspices of OECD Nuclear Agency's International Information Exchange Programme on Actinide and Fission Product Partitioning and Transmutation. In the original announcement for the meeting the following sessions were proposed: 1) Concepts of accelerator-based transmutation systems, 2) Nuclear design problems of accelerator-based transmutation systems with emphasis on target facilities and their interfaces with accelerators, 3) Data and methods for nuclear design of accelerator-based transmutation systems, 4) Related cross-section measurements and integral experiments, 5) Identification of discrepancies and gaps and discussion of desirable R+D and benchmark activities. Due to the large number of papers submitted it was necessary to split session 2 into two parts and to reassign some papers in order to balance the sessions more evenly. No papers were submitted for session 5 and this was replaced by a summary and general discussion session. These proceedings contain all 30 papers in the order they were presented at the meeting. They are copies of the duplication-ready versions given to us during or shortly after the meeting. In the Table of Contents, the papers are listed together with the name of the presenter. (author) figs., tabs., refs

  15. Studies of industrial emissions by accelerator-based techniques: A review of applications at CEDAD

    Science.gov (United States)

    Calcagnile, L.; Quarta, G.

    2012-04-01

    Different research activities are in progress at the Centre for Dating and Diagnostics (CEDAD), University of Salento, in the field of environmental monitoring by exploiting the potentialities given by the different experimental beam lines implemented on the 3 MV Tande-tron accelerator and dedicated to AMS (Accelerator Mass Spectrome-try) radiocarbon dating and IB A (Ion Beam Analysis). An overview of these activities is presented by showing how accelerator-based analytical techniques can be a powerful tool for monitoring the anthropogenic carbon dioxide emissions from industrial sources and for the assessment of the biogenic content in SRF (Solid Recovered Fuel) burned in WTE (Waste to Energy) plants.

  16. Studies of industrial emissions by accelerator-based techniques: A review of applications at CEDAD

    Directory of Open Access Journals (Sweden)

    Calcagnile L.

    2012-04-01

    Full Text Available Different research activities are in progress at the Centre for Dating and Diagnostics (CEDAD, University of Salento, in the field of environmental monitoring by exploiting the potentialities given by the different experimental beam lines implemented on the 3 MV Tande-tron accelerator and dedicated to AMS (Accelerator Mass Spectrome-try radiocarbon dating and IB A (Ion Beam Analysis. An overview of these activities is presented by showing how accelerator-based analytical techniques can be a powerful tool for monitoring the anthropogenic carbon dioxide emissions from industrial sources and for the assessment of the biogenic content in SRF (Solid Recovered Fuel burned in WTE (Waste to Energy plants.

  17. Sources of X-radiation based on stochastic acceleration of rape plasma particles

    International Nuclear Information System (INIS)

    The results of theoretical and experimental study of stochastic plasma heating are presented. The high efficiency of such heating is shown. The possibility of using such plasma as a source of X-radiation is analyzed. Such sources are compared with the closest known sources

  18. Non-radiating sources, dynamic anapole and Aharonov-Bohm effect

    CERN Document Server

    Nemkov, Nikita A; Fedotov, Vassily A

    2016-01-01

    We show that any non-radiating source can be represented by a combination of identical, spatially localized distributions of electric and toroidal point dipoles. One of the implications is that at every point of an arbitrary non-radiating source there exists a simple universal relation between the electric and toroidal dipole moments. We also present simple means of describing non-radiating sources and discuss a possible scenario for observing the time-dependent version of the Aharonov-Bohm effect in such systems.

  19. Radiation protection for patients and personnel in diagnostics and therapy with unsealed sources

    International Nuclear Information System (INIS)

    The Austrian association for radiation protection in medicine and the union of German practitioners specialized in radiation protection are joining in the task of promoting research in the field of radiation protection, intensifying the exchange of experience among the members of the society and representing the interests of medical personnel as regards radiation protection vis-a-vis interested circles of the public, the health services and similar institutions in science and practice. This range of tasks includes radiation protection of patients and personnel in diagnostics and therapy with unsealed sources. (orig./DG)

  20. III. Biological effects of radiation from external and internal sources

    Energy Technology Data Exchange (ETDEWEB)

    Stone, R.S.

    1948-05-24

    This report focuses on the hemotological effects of total body irradiation from external and internal sources observed in patients treated for arthritis with radioactive phosphorus administered intravenously.

  1. The IAEA's sub programme on the safety of radiation sources and the security of radioactive materials

    International Nuclear Information System (INIS)

    In compliance with its mandate to establish standards of safety and to provide for their application with respect to radiation sources, the International Atomic Energy Agency has developed a subprogramme aimed at providing Member States guidance and assistance on achieving regulatory control and the safe use of the sources. The guidance addresses the establishment of a Regulatory Programme, with focus on a system for notification and authorization (registration and licensing) and inspection of radiation sources, including check lists for review of safety. It also includes methods for assessing its effectiveness of the Regulatory Programme and is complemented with tools for the management of data by the Regulatory Authority and Services to assist Member States in assessment and implementation of the programme. In addition, technical guidance for the safety of radiation sources includes both prospective and retrospective safety assessment. Retrospective methods have been used resulting in the publication and dissemination of information and lessons from accidents, both individual accident reports and lessons from collection of accident for the practices with major sources (industrial radiography, irradiators and radiotherapy). Prospective methods will include guidance on the application of the principles of radiation protection to potential exposure, as well as methods to apply the principles, such as identification and evaluation of scenarios. Practice specific reports will address the major radiation sources. A research programme will be dedicated to apply Probabilistic Safety Assessment (PSA) to radiation sources. (author)

  2. Large Radiation Sources for Industrial Processes. Proceedings of a Symposium on the Utilization of Large Radiation Sources and Accelerators in Industrial Processing

    International Nuclear Information System (INIS)

    Chemical industries are progressively recognizing the usefulness of high-energy ionizing radiation for initiating chemical syntheses and polymerization reactions. Intense sources of radiation are now available both from particle accelerators and from radioisotopes produced, in quantity by nuclear reactors. The chemical reactions initiated by radiation are easily controlled: many free-radical reactions may be initiated, and for some ionic reactions, radiation obviates the need for a catalyst. Radiation processing, along with other improvements in technology, has already shown significant economic benefits in such fields as the production of composite materials and surface coatings, the modification of textiles and the processing of plastics. Following two previous meetings on the subject in Warsaw (1959) and in Salzburg (1963), the International Atomic Energy Agency convened a third Symposium, on the Utilization of Large Radiation Sources and Accelerators in Industrial Processing, in Munich from 18 to 22 August 1969. About 190 participants from 29 countries and five international organizations attended the meeting to join the discussion of 50 papers. The four main topics of the Symposium were: Chemical synthesis Polymerization and the modification of polymers Dosimetry Engineering. Many developments were reported in radiation-induced polymerization and in the modification of polymers through grafting and cross-linking. There were descriptions, not only of pilot plants, but also of the design of radiation systems for continuous-flow production. Many papers dealt both with theory and practice and some papers identified areas in which intensive research is likely to bring forth new economic applications of radiation processing. These Proceedings, containing the papers and the discussions, will, it is hoped, help to promote this technology as one of the major contributions of nuclear techniques to modern industry

  3. Natural Sources of Radiation Exposure and the Teaching of Radioecology

    Science.gov (United States)

    Anjos, R. M.; Veiga, R.; Carvalho, C.; Sanches, N.; Estellita, L.; Zanuto, P.; Queiroz, E.; Macario, K.

    2008-01-01

    We have developed an experimental activity that introduces concepts of the natural ionizing radiation and its interaction with our contemporary environment that can be used with students from secondary to college level. The experiment is based on the use of traditional and cheap portable Geiger-Muller detectors as survey meters for "in situ"…

  4. Safety of radiation sources and security of radioactive materials. A Romanian approach

    International Nuclear Information System (INIS)

    After a brief explanation on the scope of applications of nuclear energy and practices with ionizing radiation in Romania, the report explains the current national infrastructure for radiation safety making reference in particular to the National Commission for Nuclear Activities Control as the regulatory authority for the safety of radiation sources. The report also describes the existing legal framework, provides information on the list of normative acts in force, and on the system of authorization, inspection and enforcement, which operates effectively. (author)

  5. Virtual monochromatic imaging in dual-source dual-energy CT: Radiation dose and image quality

    OpenAIRE

    Yu, Lifeng; Christner, Jodie A.; Leng, Shuai; Wang, Jia; Fletcher, Joel G.; McCollough, Cynthia H.

    2011-01-01

    Purpose: To evaluate the image quality of virtual monochromatic images synthesized from dual-source dual-energy computed tomography (CT) in comparison with conventional polychromatic single-energy CT for the same radiation dose.

  6. Recommendations for the safe use and regulation of radiation sources in industry, medicine, research and teaching

    International Nuclear Information System (INIS)

    The use of radiation sources of various types and activities is widespread in industry, medicine, research and teaching, and is increasing yearly. The safety record has been admirable, although incidents have occurred where loss of control of radiation sources has given rise to unplanned exposures to workers, medical patients and members of the public, sometimes with fatal results, while in other situations exposure may not have been as low as reasonably achievable. This publication is intended as a practical aid for all concerned with operational radiation protection connected with the use of radiation sources in industry, medicine, research and teaching, from the point of view of both the user of such sources and the regulatory bodies. Refs, figs

  7. Application of the Pin Diode as a Dosimeter for Dose Measurement of Several Radiation Sources

    Science.gov (United States)

    Sopko, Vit; Dammer, Jiri; Chren, Dominik; Sopko, Bruno; Latal, Frantisek

    2010-04-01

    Experimental PIN diodes produced for measurement of low energy gamma radiation were exposed to neutron, proton and gamma radiation sources, in an attempt to expand the area of their application. Irradiation of the PIN diode resulted in changes of IV curve. The changes of voltage at certain current were recorded and depicted in graphs.

  8. Theory for beam-plasma millimeter-wave radiation source experiments

    International Nuclear Information System (INIS)

    This paper reports on theoretical studies for millimeter-wave plasma source experiments. In the device, millimeter-wave radiation is generated in a plasma-filled waveguide driven by counter-streaming electron beams. The beams excite electron plasma waves which couple to produce radiation at twice the plasma frequency. Physics topics relevant to the high electron beam current regime are discussed

  9. Source parameters and radiation efficiency for intermediate-depth earthquakes in Northeast Japan

    NARCIS (Netherlands)

    Nishitsuji, Y.; Mori, J.

    2013-01-01

    We estimated source parameters of 216 intermediate-depth (65–150 km) earthquakes (Mw 4.0–7.0) in the Pacific slab beneath Japan along using Hi-net data. We made determinations of static stress drop, radiated energy and radiation efficiency, along with estimates of the whole path attenuation, to stud

  10. Terahertz radiation source using an industrial electron linear accelerator

    CERN Document Server

    Kalkal, Yashvir

    2015-01-01

    High power ($\\sim 100$ kW) industrial electron linear accelerators (linacs) are used for irradiation applications e.g., for pasteurization of food products, disinfection of medical waste, etc. We propose that high power electron beam from such an industrial linac can be first passed through an undulator to generate powerful terahertz (THz) radiation, and the spent electron beam coming out of the undulator can still be used for industrial applications. This will enhance the utilisation of a high power industrial linac. We have performed calculation of spontaneous emission in the undulator to show that for typical parameters, continuous terahertz radiation having power of the order of $\\mu$W can be produced, which may be useful for many scientific applications.

  11. Emission of gravitational radiation from ultra-relativistic sources

    CERN Document Server

    Segalis, E B; Segalis, Ehud B.; Ori, Amos

    2001-01-01

    Recent observations suggest that blobs of matter are ejected with ultra-relativistic speeds in various astrophysical phenomena such as supernova explosions, quasars, and microquasars. In this paper we analyze the gravitational radiation emitted when such an ultra-relativistic blob is ejected from a massive object. We express the gravitational wave by the metric perturbation in the transverse-traceless gauge, and calculate its amplitude and angular dependence. We find that in the ultra-relativistic limit the gravitational wave has a wide angular distribution, like $1+\\cos\\theta$. The typical burst's frequency is Doppler shifted, with the blue-shift factor being strongly beamed in the forward direction. As a consequence, the energy flux carried by the gravitational radiation is beamed. In the second part of the paper we estimate the anticipated detection rate of such bursts by a gravitational-wave detector, for blobs ejected in supernova explosions. Dar and De Rujula recently proposed that ultra-relativistic bl...

  12. Accelerator-based conversion (ABC) of reactor and weapons plutonium

    International Nuclear Information System (INIS)

    An accelerator-based conversion (ABC) system is presented that is capable of rapidly burning plutonium in a low-inventory sub-critical system. The system also returns fission power to the grid and transmutes troublesome long-lived fission products to short lived or stable products. Higher actinides are totally fissioned. The system is suited not only to controlled, rapid burning of excess weapons plutonium, but to the long range application of eliminating or drastically reducing the world total inventory of plutonium. Deployment of the system will require the successful resolution of a broad range of technical issues introduced in the paper

  13. Determining the temperature and density distribution from a Z-pinch radiation source

    International Nuclear Information System (INIS)

    High temperature radiation sources exceeding one hundred eV can be produced via z-pinches using currently available pulsed power. The usual approach to compare the z-pinch simulation and experimental data is to convert the radiation output at the source, whose temperature and density distributions are computed from the 2-D MHD code, into simulated data such as a spectrometer reading. This conversion process involves a radiation transfer calculation through the axially symmetric source, assuming local thermodynamic equilibrium (LTE), and folding the radiation that reaches the detector with the frequency-dependent response function. In this paper the authors propose a different approach by which they can determine the temperature and density distributions of the radiation source directly from the spatially resolved spectral data. This unfolding process is reliable and unambiguous for the ideal case where LTE holds and the source is axially symmetric. In reality, imperfect LTE and axial symmetry will introduce inaccuracies into the unfolded distributions. The authors use a parameter optimization routine to find the temperature and density distributions that best fit the data. They know from their past experience that the radiation source resulting from the implosion of a thin foil does not exhibit good axial symmetry. However, recent experiments carried out at Sandia National Laboratory using multiple wire arrays were very promising to achieve reasonably good symmetry. For these experiments the method will provide a valuable diagnostic tool

  14. Polymer research at synchrotron radiation sources: symposium proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Russell, T.P.; Goland, A.N. (eds.)

    1985-01-01

    The twenty-two papers are arranged into eleven sessions entitled: general overviews; time-resolved x-ray scattering; studies using fluorescence, ion-containing polymers; time-resolved x-ray scattering; novel applications of synchrotron radiation; phase transitions in polymers; x-ray diffraction on polymers; recent detector advances; complementary light, x-ray and neutron studies; and neutron scattering studies. Seven of the papers are processed separately; three of the remainder have been previously processed. (DLC)

  15. Polymer research at synchrotron radiation sources: symposium proceedings

    International Nuclear Information System (INIS)

    The twenty-two papers are arranged into eleven sessions entitled: general overviews; time-resolved x-ray scattering; studies using fluorescence, ion-containing polymers; time-resolved x-ray scattering; novel applications of synchrotron radiation; phase transitions in polymers; x-ray diffraction on polymers; recent detector advances; complementary light, x-ray and neutron studies; and neutron scattering studies. Seven of the papers are processed separately; three of the remainder have been previously processed

  16. Crossed undulator system for a variable polarization synchrotron radiation source

    International Nuclear Information System (INIS)

    A crossed undulator system can produce synchrotron radiation whose polarization is arbitrary and adjustable. The polarization can be linear and modulated between two mutually perpendicular directions, or it can be circular and can be modulated between right and left circular polarizations. The system works on low emittance electron storage rings and can cover a wide spectral range. Topics discussed include the basic principle of the system, the design equations and the limitations in performance

  17. Radiation Tolerant Low Power Precision Time Source Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The availability of small, low power atomic clocks is now a reality for ground-based and airborne navigation systems. Kernco's Low Power Precision Time Source...

  18. Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards. General Safety Requirements. Pt. 3 (Chinese Edition)

    International Nuclear Information System (INIS)

    This publication is the new edition of the International Basic Safety Standards. The edition is co-sponsored by seven other international organizations — European Commission (EC/Euratom), FAO, ILO, OECD/NEA, PAHO, UNEP and WHO. It replaces the interim edition that was published in November 2011 and the previous edition of the International Basic Safety Standards which was published in 1996. It has been extensively revised and updated to take account of the latest finding of the United Nations Scientific Committee on the Effects of Atomic Radiation, and the latest recommendations of the International Commission on Radiological Protection. The publication details the requirements for the protection of people and the environment from harmful effects of ionizing radiation and for the safety of radiation sources. All circumstances of radiation exposure are considered

  19. The spacetime outside a source of gravitational radiation: The axially symmetric null fluid

    CERN Document Server

    Herrera, L; Ospino, J

    2016-01-01

    We carry out a study of the exterior of an axially and reflection symmetric source of gravitational radiation. The exterior of such a source is filled with a null fluid produced by the dissipative processes inherent to the emission of gravitational radiation, thereby representing a generalization of the Vaidya metric for axially and reflection symmetric spacetimes. The role of the vorticity, and its relationship with the presence of gravitational radiation is put in evidence. The spherically symmetric case (Vaidya) is, asymptotically, recovered within the context of the $1+3$ formalism.

  20. Polycapillary X-ray lens for the secondary focusing Beijing synchrotron radiation source

    Institute of Scientific and Technical Information of China (English)

    Li Yu-De; Lin Xiao-Yan; Liu Shi-Gang; He Jin-Long; Guo Fei; Sun Tian-Xi; Liu Peng

    2013-01-01

    According to intensity distribution of the synchrotron radiation source focused by a toroidal mirror at the Beijing synchrotron radiation biological macromolecule station,theoretical modeling of the Beijing synchrotron radiation source is developed for capillary optics.Using this theoretical modeling,the influences of the configuration curve of the polycapillary X-ray lens on transmission efficiency and working distance are analyzed.The experimental results of the transmission efficiency and working distance at the biological macromolecule station are in good agreement with the theoretical results.

  1. The Radiation Dose Determination of the Pulsed X-ray Source

    Science.gov (United States)

    Miloichikova, I.; Stuchebrov, S.; Zhaksybayeva, G.; Wagner, A.

    2014-10-01

    In this paper the radiation dose measurement technique of the pulsed X-ray source RAP-160-5 is described. The dose rate measurement results from the pulsed X-ray beams at the different distance between the pulsed X-ray source focus and the detector obtained with the help of the thermoluminescent detectors DTL-02, the universal dosimeter UNIDOS E equipped with the plane-parallel ionization chamber type 23342, the dosimeter-radiometer DKS-96 and the radiation dosimeter AT 1123 are demonstrated. The recommendations for the dosimetry measurements of the pulsed X-ray generator RAP-160-5 under different radiation conditions are proposed.

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

    International Nuclear Information System (INIS)

    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 latter 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. (author)

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lombardo, J.H.; Smolko, E.E. (Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

    1990-01-01

    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 latter 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. (author).

  5. Assessment of occupational exposure due to external sources of radiation. Safety guide

    International Nuclear Information System (INIS)

    Occupational exposure to ionizing radiation can occur in a range of industries, medical institutions, educational and research establishments and nuclear fuel cycle facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The Agency gratefully acknowledges the contribution of the European Commission to the development of the present Safety Guide. The present Safety Guide addresses the assessment of exposure due to external sources of radiation in the workplace. Such exposure can result from a number of sources within a workplace, and the monitoring of workers and the workplace in such situations is an integral part of any occupational radiation protection programme. The assessment of exposure due to external radiation sources depends critically upon knowledge of the radiation type and energy and the conditions of exposure. The present Safety Guide reflects the major changes over the past decade in international practice in external dose assessment

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

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    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 Fn 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.

  7. Monitoring Of Radiation Exposure Source In PPTA Serpong

    International Nuclear Information System (INIS)

    The radiation exposure in the of P PTA Serpone was measured by means of MCA micro nomad. The computer codes NAGABAT was used for analyzing the contribution of natural gamma rays to the exposure rate in the measuring locations. Measurement was taken for 14 locations, under conditions that the nuclear facilities are not in operation. The result showed that the exposure varieties, dependently on potassium, uranium and thorium contents in the environment matrix. The maximum of thorium, uranium and potassium are in amount of 5,269 ppm; 1,650 ppm; and respectively 0,72 %

  8. Synchrotron radiation as a light source in confocal microscopy

    Energy Technology Data Exchange (ETDEWEB)

    van der Oord, C.J.R.; Gerritsen, H.C.; Levine, Y.K. (University of Utrecht, P.O. Box 80.000, 3508 TA Utrecht (Netherlands)); Myring, W.J.; Jones, G.R.; Munro, I.H. (Daresbury Laboratory (United Kingdom))

    1992-01-01

    The optical properties of a confocal scanning microscope that was designed to utilize a synchrotron as light source are presented. The usable spectral range is from 200 nm up to 700 nm. Using 325-nm laser light, it is shown that the lateral resolution is about 125 nm, and the axial resolution better than 250 nm. After transport of the microscope from Utrecht to the Daresbury Synchrotron Source, 200-nm excitation can be applied, and the lateral resolution will drop to below 100 nm.

  9. A Far-Infrared FEL for the Radiation Source ELBE

    CERN Document Server

    Seidel, W; Lehnert, U; Michel, P; Schlenk, R; Willkommen, U; Wohlfarth, D; Wünsch, R

    2005-01-01

    After successfully commissioning the mid-infrared FEL (U27) and adjoining a second accelerator unit (up to 35 MeV) at ELBE we have modified our plan how to produce radiation in the far infrared.To ensure the continuous variation of the wavelength up to 150 microns we want to complement the U27 undulator by a permanent magnet undulator with a period of 100 mm (U100). The minimum gap of 24 mm and the hybrid construction consisting of Sm/Co magnets and soft iron poles ensures sufficient radiation resistance and allows rms undulator parameters up to 2.7. The large field variation allows us to cover the whole wavelength range by only two different electron energies (e.g. 20 and 35 MeV). To reduce the transverse beam size we use a partial waveguide which is 10 mm high and wide enough to allow free propagation in horizontal direction. It spans from the last quadrupole in front of the undulator up to the downstream mirror and is somewhat longer than 8 m. To minimize the coupling losses between free propagation and th...

  10. Internet as a Source of Misconception: "Radiation and Radioactivity"

    Science.gov (United States)

    Acar Sesen, Burcin; Ince, Elif

    2010-01-01

    The purpose of this study is to examine students' usage styles of the Internet for seeking information and to investigate whether information obtained from the Internet is a source of misconceptions. For this reason, a two-stage study was conducted. At the first stage, a questionnaire was developed to get information about students' Internet usage…

  11. Dazzling new light source opens at Stanford synchrotron radiation laboratory

    CERN Multimedia

    2004-01-01

    SPEAR3, the Stanford Positron Electron Asymmetric Ring, was formally opened at a dedication ceremony at the Stanford Linear Accelerator Center on Jan. 29. It incorporates the latest technology to make it competitive with the best synchrotron sources in the world (1/2 page)

  12. Safety assessment of the disposal of sealed radiation sources in boreholes

    International Nuclear Information System (INIS)

    The Radioactive Waste Management Laboratory (RNML) at the Nuclear Energy Research Institute (NERI) in Sao Paulo, Brazil, is developing the concept of a repository for disused sealed radiation sources in a deep borehole. Several thousands disused sealed radiation sources are stored at NERI awaiting the decision on final disposal and tens of thousands are still under the possession of the licensees. A significant fraction of these sources are long-lived and will require final disposal in a geological repository. The purpose of this paper is to identify and discuss suitable safety assessment strategies for the repository concept and to illustrate a rational approach for a long-term safety assessment methodology. (author)

  13. Control of the safety of radiation sources and the security of radioactive materials

    International Nuclear Information System (INIS)

    Since its creation in 1950, the National Atomic Energy Commission (CNEA) of Argentina, was established as the competent authority in the control of nuclear applications in relation to the protection against the hazardous effects of ionizing radiation and the safety of installations. In 1958, the Executive issued Decree 842 approving the Regulation for Using Radioisotopes and Ionising Radiations, to control use and application of radioactive materials and radiation emitted by them or from nuclear reactions. A part of the CNEA, the Regulatory Branch, was then formed and very rapidly established itself as the national authority in the areas of radiation and nuclear safety, safeguards and non-proliferation assurances, and physical protection. In the present paper, only the control of radioactive sources will be presented. The Nuclear Regulatory Authority (ARN) is empowered to establish standards and enforce their application to the possession and use of radiation sources. The regulatory goals are: ensure that the radioactive materials are imported, exported produces, transferred, stored, used, or disposed of, only by registrants or licensed persons in authorised or licensed installations, as required by Argentine regulations; ensure that registrants or licensees do everything reasonable and compatible with their possibilities regarding safety and security of radiation sources; ensure that the radioactive materials are handed over to another user, or are disposed of as radioactive waste, only when transfer or disposal was specifically authorised by the Regulatory Authority; keep an updated database of all the sealed radioactive sources in use in the country; prevent the illicit traffic of radiation sources; ensure safety and security of disused radioactive sealed sources, doing whatever necessary to maintain the required control; ensure that technical characteristics of imported of locally produced radioactive sources comply with Argentine safety requirements

  14. Radiation safety supervisory system in Latvia and its role in prevention of unauthorised practices with radiation sources

    International Nuclear Information System (INIS)

    This report provides an overview of the practical and legal aspects of the use of radiation sources. The existing regulatory infrastructure is briefly analysed and proposed systems are described. The proposed interactions between the regulatory body and the advisory board are presented and some details about joint activities of different institutions concerning radiation safety are given. An implementation example of the supervisory system in combating illicit trafficking is analysed and the essential components in the prevention of illicit trafficking are assessed. Some findings of investigations are quoted regarding improvements in protection and prevention on the national and the international level. (author)

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

    Science.gov (United States)

    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. PMID:26837023

  16. Polarization effects in radiation from compact X-ray sources

    International Nuclear Information System (INIS)

    A theory of polarization of X rays emitted by magnetized neutron stars, white dwarfs and black hole accretion disks is presented and predictions are compared with polarimetric data. Polarization occurs in accreting neutron stars and white dwarfs in binary systems as plasma travels along magnetic field lines formed between the companions. Movement parallel to the field produces circular polarization, transverse propagation yields linear polarization and elliptical polarization arises from other angles. The actual mechanism is alterations in the absorption coefficients of magnetized plasma, changes introduced by available bremsstrahlung and electron scattering processes. Thomson scattering is an origin of X ray polarization in black hole and neutron star accretion disks, with the type of polarization being dependent on the radiation density near the boundary, the presence of Faraday rotation and the geometry of the disk magnetic field. Polarimetric data on 10 stellar objects are presented as supportive evidence for the theory. 14 references

  17. Physics and dosimetry aspects of synchrotron radiation sources

    International Nuclear Information System (INIS)

    Today there is a growing need in the use of accelerators for various applications in the field of medicine, industry, defense, environmental sciences, food processing and in basic and applied research. Electron accelerators are widely used nowadays in the field of diagnosis, therapy, radiography, basic research, production of synchrotron radiation etc. For applications in medicine, industry and food processing, the energy of the accelerated electrons is usually less than about 10 MeV whereas it may extend to several TeV for research applications. Most of the high energy accelerators use radio-frequency for the acceleration and hence the particle beam is bunched or pulsed. The increase in the use of such machines with higher accelerated energy and pulsed in nature raises several safety issues

  18. Admixtures in Spent Plutonium Sources and Gamma-Radiation

    Directory of Open Access Journals (Sweden)

    Inga Pelanytė

    2011-04-01

    Full Text Available The isotopic composition of several spent smoke detectors containing plutonium has been investigated. The article also presents the calculated results of 241Am and 241Pu activities in smoke detectors. The received values vary from (0.934±0.028 MBq to (91.2±4.6 MBq. The eguivalent dose rate of the established gamma radiation vary from 220 nSv/h to 500 nSv/h. A dose caused by artificial radionuclides in spent smoke detectors was evaluated and compared in the article. It has been found out that due to smoke detectors, an annual dose varies from 0.06 mSv to 0.31 mSv. Article in Lithuanian

  19. High-energy gamma radiation from extragalactic radio sources

    Science.gov (United States)

    Dermer, C. D.; Schlickeiser, R.; Mastichiadis, A.

    1992-01-01

    We propose that the important relationship between 3C 273 and 3C 279, the first two extragalactic sources detected at over 100 MeV energies, is their superluminal nature. In support of this conjecture, we propose a kinematic focusing mechanism, based on Compton scattering of accretion-disk photons by relativistic nonthermal electrons in the jet, that preferentially emits gamma rays in the superluminal direction.

  20. Characteristics and development of the coherent synchrotron radiation sources for THz spectroscopy

    Science.gov (United States)

    Barros, J.; Evain, C.; Roussel, E.; Manceron, L.; Brubach, J.-B.; Tordeux, M.-A.; Couprie, M.-E.; Bielawski, S.; Szwaj, C.; Labat, M.; Roy, P.

    2015-09-01

    We report on the characteristics of coherent synchrotron radiation (CSR) as a source for spectroscopy. The optimization of the source and the resulting figures of merits in terms of flux, signal to noise, spatial distribution and spectral and temporal distribution are presented together with a spectroscopic application. The emission of THz during the slicing operation is also described. The conclusion opens up perspectives made possible by the availability of this intense and stable THz source.

  1. Synthesis of Fourier holograms for recognition of radiation sources with continuous spectra by dispersive correlators

    Science.gov (United States)

    Molodtsov, D. Y.; Rodin, V. G.; Starikov, S. N.

    2015-05-01

    Dispersive correlators have been proposed previously for solving problems of recognition of radiating objects in real time. Correlation signals are formed by radiation of analyzed object during its interaction with spatial filter. Most difficult recognition case is when spectrum of input radiation is continuous (non-line spectrum). Method of synthesis of Fourier holograms for their using in dispersive correlators as spatial filters is developed in this work. Spectral ranges, in which values of components of radiation are greater than predetermined threshold for reference spectrum, were determined. Entrance slit used as reference object. Next, spatial image of spectrum, which is a set of images of object (slit), was formed. Amount of object images and its sizes are determined with selected wavelength ranges. Fourier hologram of this image was computer synthesized and had 2048x2048 pixels. Then this hologram was binarized and printed using laser imagesetter with 100 dots/mm resolution. In this work the scheme of the dispersive correlator with single Fourier-objective was used. Correlation signals for different spectra were experimentally formed. LEDs, including RGB-LED with ability of dynamically changing of composition of radiation spectrum, were used as radiation sources. Post-processing operations, which provide independence of recognition results from radiation source power and holograms diffraction efficiency, were defined. Three methods of normalization of correlation signal for identification signal obtaining were experimentally tested and compared. These methods are normalization to radiation power in zero, first, and both of these diffraction orders. Experimental results on identification of test sources with non-line radiation spectra are obtained. They show successful recognition of used LED sources of different colors. Average ratio of spectra coincidence signal to mismatch signal was 4.6 at relative spectral resolution of used setup equaled to 0.004.

  2. Comparison of radiation sources and filtering safety glasses for fluorescent nondestructive evaluation

    Science.gov (United States)

    Lopez, Richard Daniel

    This study was directed toward the question of whether recent advancements in radiation sources and test media offered significant improvements over the current state of the art. Included were experiments characterizing common penetrant and magnetic particle materials to determine their fluorescent excitation spectra, and a comparison between the fluorescent excitation spectra and the emission spectra of common excitation sources. The relationship between exciter and test medium directly controls the luminance of a defect indication. As indication luminance increases, the probability of it being detected by the inspector increases. Fluorescent penetrant and magnetic particle test media were originally designed around the widely available filtered medium pressure mercury vapor lamp, which remains the standard excitation radiation source. Test media properties, and the types of available excitation sources have changed with time, and it was unclear whether present-day media was still best excited by the historical standard ultraviolet radiation source. Predictions and experimental work was performed to determine the optimal excitation source for fluorescent nondestructive testing, and to determine which safety lens option would offer the highest probability of detection. Improvement in radiation sources was primarily judged by an increase in fluorophore luminance versus background, which led to an increase in signal-to-noise ratio facilitating better indication detectability. Other factors considered were improved health and safety, and ease of use.

  3. Radiative feedback and cosmic molecular gas: the role of different radiative sources

    CERN Document Server

    Maio, U; De Lucia, G; Borgani, S

    2016-01-01

    We present results from multifrequency radiative hydrodynamical chemistry simulations addressing primordial star formation and related stellar feedback from various populations of stars, stellar energy distributions (SEDs) and initial mass functions. Spectra for massive stars, intermediate-mass stars and regular solar-like stars are adopted over a grid of 150 frequency bins and consistently coupled with hydrodynamics, heavy-element pollution and non-equilibrium species calculations. Powerful massive population III stars are found to be able to largely ionize H and, subsequently, He and He$^+$, causing an inversion of the equation of state and a boost of the Jeans masses in the early intergalactic medium. Radiative effects on star formation rates are between a factor of a few and 1 dex, depending on the SED. Radiative processes are responsible for gas heating and photoevaporation, although emission from soft SEDs has minor impacts. These findings have implications for cosmic gas preheating, primordial direct-c...

  4. Sources and effects of ionizing radiation. UNSCEAR 1996 report to the General Assembly, with scientific annex

    International Nuclear Information System (INIS)

    During the last few years the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has undertaken a broad review of the sources and effects of ionizing radiation. The results of this work have been issued in a series of publications: the UNSCEAR 1993 Report with nine scientific annexes, the UNSCEAR 1994 Report with two scientific annexes and the present UNSCEAR 1996 Report with one scientific annex, ''Effects of radiation on the environment''. These three publications from a series of reports entitled Sources and Effects of Ionizing Radiation, which together inform the General Assembly and the scientific and world community of the Committee's latest findings and evaluations. The Committee considers in this report the effects of ionizing radiation on plants and animals in the environment. These effects have not previously been addressed directly by the Committee. The emphasis of past assessments has been on determining the effects of radiation on human health. With the increasing interest around the world in nurturing the environment and concerns about possible detrimental effects of radiation, the time is appropriate for the Committee to provide a summary of the effects of radiation on the environment. Refs, figs, tabs

  5. Characteristics of synchrotron radiation and of its sources

    International Nuclear Information System (INIS)

    Synchrotron light emission and the classical relativistic electromagnetic theory describing it are reviewed. The electron optics of storage rings are considered in some detail, beginning with the ideal electron orbit and the distribution which electrons take around it. This is folded with the process of synchrotron light emission itself to define the effective photon source. The predictions of classical relativistic theory are compared with experiment, and one finds agreement within the experimental uncertainties. Further refinements, such as wiggler magnets and free electron lasers are also considered

  6. Safety and security of radiation sources and radioactive materials: A case of Zambia - least developed country

    International Nuclear Information System (INIS)

    In Zambia, which is current (1998) classified as a Least Developed Country has applications of nuclear science and technology that cover the medical, industrial, education and research. However, the application is mainly in medical and industry. Through the responsibility of radiation source is within the mandate of the Radiation Protection Board. The aspects involving security fall on different stake holders some that have no technical knowledge on what radiation is about. The stake holders in this category include customs clearing and forwarding agents, state security/defence agencies and the operators. Such a situation demands a national system that should be instituted to meet the safety and security requirements but takes into account the involvement of the diverse stake holders. In addition such system should avoid unnecessary exposure, ensure safety of radioactive materials and sources, detect illicit trade and maintain integrity of such materials or sources. This paper will provide the status on issue in Zambia and the challenges that exist to ensure further development in application of Nuclear Science and Technology (S and T) in the country takes into account the safety and security requirements that avoid deliberate and accidental loss of radiation sources and radioactive materials. The Government has a responsibility to ensure that effective system is established and operated to protect radiation sources and radioactive materials from theft, sabotage and ensure safety. (author)

  7. High power bremsstrahlung X-ray source for radiation processing

    Science.gov (United States)

    Yotsumoto, K.; Sunaga, H.; Tanaka, S.; Kanazawa, T.; Agematsu, T.; Tanaka, R.; Yoshida, K.; Taniguchi, S.; Sakamoto, I.; Tamura, N.

    The high power X-ray irradiation facility designed for the sterilization of medical appliances is described. The X-ray source consists of the 5 MeV, 300 kW Cockcroft Walton type of electron accelerator and the water cooled tantalum target. Conditions necessary for designing the X-ray target are conversion efficiency from electron beam to X-ray, thermal conductivity, readiness for machining and cost of the material. The conversion efficiency was determined through the Monte Carlo type calculation and obtained as 10.8 % for 3.667 g/cm 2 thickness (1 csda range) of tantalum target. In order to obtain the data on the source design, experiments have been carried out at the JAERI TAKASAKI 2 MeV, 60 kW Cockcroft-Walton type of electron accelerator equipped with a tantalum target. The size of package and the speed of conveyor was determined through the calculation of the absorbed dose distribution in the irradiated medium and the utilization efficiency.

  8. Projection of needs for gamma radiation sources and other radioisotopes and assessment of alternatives for providing radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Ross, W.A.; Jensen, G.A.; Clark, L.L.; Eakin, D.E.; Jarrett, J.H.; Katayama, Y.B.; McKee, R.W.; Morgan, L.G.; Nealey, S.M.; Platt, A.M.; Tingey, G.L.

    1989-06-01

    Pacific Northwest Laboratory reviewed the projected uses and demands for a variety of nuclear byproducts. Because the major large-scale near-term demand is for gamma irradiation sources, this report concentrates on the needs for gamma sources and evaluates the options for providing the needed material. Projections of possible growth in the irradiation treatment industry indicate that there will be a need for 180 to 320 MCi of /sup 60/Co (including /sup 137/Cs equivalent) in service in the year 2000. The largest current and projected use of gamma irradiation is for the sterilization of medical devices and disposable medical supplies. Currently, 40% of US disposable medical products are treated by irradiation, and within 10 years it is expected that 90% will be treated in this manner. Irradiation treatment of food for destruction of pathogens or parasites, disinfestation, or extension of allowable storage periods is estimated to require an active inventory of 75 MCi of /sup 60/Co-equivalent gamma source in about a decade. 90 refs., 7 figs., 25 tabs.

  9. Projection of needs for gamma radiation sources and other radioisotopes and assessment of alternatives for providing radiation sources

    International Nuclear Information System (INIS)

    Pacific Northwest Laboratory reviewed the projected uses and demands for a variety of nuclear byproducts. Because the major large-scale near-term demand is for gamma irradiation sources, this report concentrates on the needs for gamma sources and evaluates the options for providing the needed material. Projections of possible growth in the irradiation treatment industry indicate that there will be a need for 180 to 320 MCi of 60Co (including 137Cs equivalent) in service in the year 2000. The largest current and projected use of gamma irradiation is for the sterilization of medical devices and disposable medical supplies. Currently, 40% of US disposable medical products are treated by irradiation, and within 10 years it is expected that 90% will be treated in this manner. Irradiation treatment of food for destruction of pathogens or parasites, disinfestation, or extension of allowable storage periods is estimated to require an active inventory of 75 MCi of 60Co-equivalent gamma source in about a decade. 90 refs., 7 figs., 25 tabs

  10. Radiation emission characteristics in the x-ray/EUV from spherically pinched and vacuum spark sources

    International Nuclear Information System (INIS)

    Extensive research and development have been pursued worldwide on various schemes of plasma radiation sources, such as the laser-plasma X-ray source, the dense plasma focus, and the spherical pinch. At Advanced Laser and Fusion Technology (ALFT), a prototype spherical pinch X-ray source, SPX II, and a commercial machine, SPX III, have been developed as broadband radiation sources. More recently, an alternative and complementary X-ray device, the vacuum spark VSX I, has been developed The spherical pinch is a novel concept based on the principle of strong spherically convergent shock waves compressing a performed plasma in the center of a spherical vessel. The vacuum spark is essentially a capacitor discharge through two properly shaped electrodes in a high vacuum environment (pressure around 1 x 10-5 Torr). During the discharge minute spots of high temperature plasmas are formed in the vicinity of the anode and strong line radiation, characteristic of the electrode material, can be generated in the soft X-ray region. The work on the spherical pinch sources, SPX II and SPX III, are described in terms of their specifications and radiation output, and on the vacuum spark source, VSX I, is presented in terms of its setup and experimental results

  11. UY 102 standard use of sealed sources in radiation source implants: approve for the Industry Energy and Mining Ministry 28/6/2002 Resolution

    International Nuclear Information System (INIS)

    Establish minimal requires for radiological safety applied to use of the solid radio actives sources with therapeutic purposes in application radiation source implants in surface area and intra cavities

  12. The regulatory infrastructure for radiation protection, the safety of radiation sources and security of radioactive materials in Ethiopia

    International Nuclear Information System (INIS)

    The application of Nuclear Techniques in Ethiopia started in the early sixties in the medical field and through time has gradually expanded to other areas. Following this growth the practice of Radiation Protection in Ethiopia dates back over 15 years. Radiation Protection Legislation 79/1993 was promulgated in December 1993, which has established an Autonomous Regulatory Authority to control and supervise the introduction and conduct of any practice involving ionizing radiation. Since 1998 the National Radiation Protection Authority has made a remarkable progress in terms of building a National Radiation Protection Infrastructure and is in a full swing transformation process towards a dynamic credible and competent regulatory Authority. The regulatory activities are designed in line with the main regulatory instruments, Notification, Authorization, Inspection and Enforcement. NRPA has a national inventory system and fully implemented the Regulatory Authority Information System (RAIS), which provides a systemic integration and will be instrumental to enhance the effectiveness of the regulatory system. A substantial progress has been made in the development and provision of support and technical services in the areas of Metrology and Calibration Services, Instrument Maintenance Service, Individual Monitoring of Personnel, Environmental and Food Monitoring and Interim Storage Facility for spent sources. Development of a national system for emergency preparedness and response is the current top agenda of NRPA. Towards ensuring an effective radiation protection and regulatory programme, NRPA is also making a proactive involvement in, expanding its outreach, information dissemination, awareness promotion and development of key human resources. In the last four years Ethiopia has been actively co-operating with IAEA in the framework of the Regional Model Projects RAF/9/024, RAF/9/028 and RAF/9/029. The inputs received through the project framework coupled with the

  13. Single window for issuing licenses for export and import of ionizing radiation sources and transit of radioactive sources

    International Nuclear Information System (INIS)

    In this paper we present the electronic system for application and issuing licenses for export, import and transit of goods (EXIM), particularly for ionizing radiation sources, in the Republic of Macedonia. This system is a modern and helpful tool for simple issuing licenses, for establishing a unique database and it represents a harmonized system for exchanging information between the governmental, public and private legal persons in the Republic of Macedonia. (author)

  14. Quantifying the contributions of individual NO x sources to the trend in ozone radiative forcing

    Science.gov (United States)

    Dahlmann, K.; Grewe, V.; Ponater, M.; Matthes, S.

    2011-06-01

    Source attribution of ozone radiative forcing (RF) is a prerequisite for developing adequate emission mitigation strategies with regards to climate impact. Decadal means of ozone fields from transient climate-chemistry simulations (1960-2019) are analysed and the temporal development of ozone RF resulting from individual NO x sources, e.g. road traffic, industry and air traffic, is investigated. We calculated an ozone production efficiency which is mainly dependent on the altitude of NO x emission and on the amount of background NO x with values varying over one order of magnitude. Air traffic and lightning are identified as NO x sources with a two and five times higher ozone production efficiency, respectively, than ground based sources. Second, radiative efficiency of source attributed ozone (i.e. total induced radiative flux change per column ozone) shows clear dependence on latitudinal structure of the ozone anomaly and, to a lesser extent, to its altitude. Lightning induced ozone shows the highest radiative efficiency because lightning primarily enhances ozone in low latitudes in the mid-troposphere (higher altitudes). Superimposed on these effects, a saturation effect causes a decreasing radiative efficiency with increasing background ozone concentrations. Changes in RF attributed to NO x induced ozone from 1960 to 2019 are controlled by three factors: changes in emissions, changes in ozone production efficiency and changes in the radiative efficiency. Leading effect is emission increase, but changes in ozone production efficiency increase ozone RF by a factor of three for air traffic, or reduce ozone RF by around 30% for ships. Additionally, changes in the radiative efficiency due to saturation effects change ozone RF by 2-5%.

  15. Hilbert Spectral Analysis of THz Radiation Sources by High-Tc Josephson Detectors

    Science.gov (United States)

    Divin, Yuriy; Lyatti, Matvey; Poppe, Ulrich

    A Hilbert spectrum analyzer was developed and characterized with monochromatic radiation sources at the frequency range from 30 GHz to 1 THz. The analyzer was based on a high-Tc frequency-selective Josephson detector and cooled to temperatures of 60-80K by a Stirling cryocooler. The instrumental function of the spectrum analyzer was shown to be of Lorentz type and within accuracy up to 0.1% without any harmonic and subharmonic contributions. Spectral characterization of THz sources, based on frequency multiplication of input microwave radiation by Schottky diodes, was demonstrated for input frequencies from 10 to 20 GHz with a total scanning time as low as 50 ms per scan. The developed Hilbert spectrum analyzer might be considered as a compact and high-speed substitute of conventional Fourier spectrometers, which are used for characterization of THz radiation sources in combination with liquid-helium-cooled silicon bolometers.

  16. Systems analysis and engineering of the X-1 Advanced Radiation Source

    International Nuclear Information System (INIS)

    The X-1 Advanced Radiation Source, which will produce ∼ 16 MJ in x-rays, represents the next step in providing US Department of Energy's Stockpile Stewardship program with the high-energy, large volume, laboratory x-ray sources needed for the Radiation Effects Science and Simulation (RES), Inertial Confinement Fusion (ICF), and Weapon Physics (WP) Programs. Advances in fast pulsed power technology and in z-pinch hohlraums on Sandia National Laboratories' Z Accelerator in 1997 provide sufficient basis for pursuing the development of X-1. This paper will introduce the X-1 Advanced Radiation Source Facility Project, describe the systems analysis and engineering approach being used, and identify critical technology areas being researched

  17. Combined sensors for the detection, identification and monitoring of radiation sources

    International Nuclear Information System (INIS)

    Radiation sources widely used in industry, medicine, agriculture. Research and education are the most dangerous from the viewpoint of their widespread and easy access.The probability that these sources will be stolen and used to assemble a radiological dispersive (RDD) is nor negligible. Such a device can be used by terrorist groups for the purpose of contamination of industrial centers, airports, seaports and residential areas, which can affect a large sector of the economy of a country. Detonation of a RDD can lead to death and exposure of the population to radiation, but, as a whole, the use of the bomb is aimed at creating panic among population, causing economic damage and social shock to the society. In this work, ways to reduce the threat of radiation sources obtained outside and within a country will be discussed

  18. The status of safety of radiation sources and security of radioactive materials in Ethiopia

    International Nuclear Information System (INIS)

    Since 1993, the National Radiation Protection Authority (NRPA) has been empowered by the 'Radiation Protection Proclamation no. 79/1993' to authorize and inspect regulated activities, issue guidelines and standards and enforce the legislation and regulations. The report describes the status of the safety of radiation sources and the security of radioactive materials in Ethiopia and the progress made towards building a sound and effective national regulatory infrastructure. Also, the report highlights the challenges and difficulties encountered and concludes by indicating the way forward towards the strategic goals. (author)

  19. High-power beam-based coherently enhanced THz radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yuelin; /Argonne; Sun, Yin-E; /Argonne /Fermilab; Kim, Kwang-Je; /Argonne

    2008-08-01

    We propose a compact Smith-Purcell radiation device that can potentially generate high average power THz radiation with high conversion efficiency. The source is based on a train of short electron bunches from an rf photoemission gun at an energy of a few MeV. Particle tracking simulation and analysis show that, with a beam current of 1 mA, it is feasible to generate hundreds of watts of narrow-band THz radiation at a repetition rate of 1 MHz.

  20. Environmental radiation control and quality management system in design and operation of sealed radioactive sources

    International Nuclear Information System (INIS)

    New environmental regulations and radiation safety standards are being implemented almost daily to ensure radiation safety, in particular for practices causing exposures to undue radiation doses. A particular emphasis of real challenge for organizations and users of radiation sources has to be for proper radiological safety assessment and is becoming cost effectively to be prepared for auditing. Special concern for the environment is of global . nature, and hence environmental auditing has been and will continue to be an essential practice for improving the environment and for meeting the relevant regulations and standards. In general, most facilities that deal with radioactive sources undertake strict safety measures in terms of personnel radiation protection, handling procedures and security. Hence, those measures should comply with the requirements of the environmental protection standards. Accordingly, a successful quality management system must balance realities of organization and personnel in achieving quality objectives. Organizational principles are found in the technical aspects of' quality management, such as, charting, requirements, measurements, procedures, ... , etc. Human principles are found in the communication side of quality management (e.g. meetings, ,decision making, ,teams, ... , etc). The quality management must understand and balance skills needed to blend them together. Large gamma irradiators present a high potential radiation hazard to the surrounding environment, since the amount of radioactivity is of the order of (P Bq) and a very high dose rates are produced during irradiation. Application of environmental radiation control deemed by regulatory authority and a proper quality management system by the utility would serve public health and safety

  1. Robust and Scalable Tracking of Radiation Sources with Cheap Binary Proximity Sensors

    CERN Document Server

    Baidoo-Williams, Henry E

    2016-01-01

    We present a new approach to tracking of radiation sources moving on smooth trajectories which can be approximated with piece-wise linear joins or piece-wise linear parabolas. We employ the use of cheap binary proximity sensors which only indicate when a radiation source enters and leaves its sensing range. We present two separate cases. The first is considering that the trajectory can be approximated with piece-wise linear joins. We develop a novel scalable approach in terms of the number of sensors required. Robustness analysis is done with respect to uncertainties in the timing recordings by the radiation sensors. We show that in the noise free case, a minimum of three sensors will suffice to recover one piece of the linear join with probability one, even in the absence of knowledge of the speed and statistics of the radiation source. Second, we tackle a more realistic approximation of trajectories of radiation sources -- piece-wise parabolic joins -- and show that no more than six sensors are required in ...

  2. Z mode radiation in Jupiter's magnetosphere: The source of Jovian continuum radiation

    International Nuclear Information System (INIS)

    Voyager spacecraft observations of Z mode waves in Jupiter's magnetosphere are analyzed. The signal appears in wideband spectrograms as an intense narrowband emission separated from the broadband continuum radiation seen at higher frequencies by a deep emission gap. The assumption that the intensity minimum corresponds to the electron plasma frequency organizes the data very well and provides a consistent interpretation of all spectral features in terms of plasma resonances and cutoffs. Several examples are given which demonstrate that the continuum radiation is composed of both left-hand and right-hand polarized wavs with distinct cutoffs observed at the plasma frequency and right-hand cutoff frequency, respectively. A survey of a representative sample of events reveals that the Z mode peak frequency lies close to the left-hand cutoff frequency, suggesting that the observed characteristics of the emission are the result of wave reflection at the cutoff layer. In a substantial number of events, another distinct emission occurring near the upper hybrid resonance frequency is detected simultaneously with the Z mode. The entire set of observations gives strong support to the linear mode conversion theory of upper hybrid waves to continuum radiation mediated by the Z mode via the Budden radio window mechanism

  3. Radiative feedback and cosmic molecular gas: the role of different radiative sources

    Science.gov (United States)

    Maio, Umberto; Petkova, Margarita; De Lucia, Gabriella; Borgani, Stefano

    2016-08-01

    We present results from multifrequency radiative hydrodynamical chemistry simulations addressing primordial star formation and related stellar feedback from various populations of stars, stellar spectral energy distributions (SEDs) and initial mass functions. Spectra for massive stars, intermediate-mass stars and regular solar-like stars are adopted over a grid of 150 frequency bins and consistently coupled with hydrodynamics, heavy-element pollution and non-equilibrium species calculations. Powerful massive Population III stars are found to be able to largely ionize H and, subsequently, He and He+, causing an inversion of the equation of state and a boost of the Jeans masses in the early intergalactic medium. Radiative effects on star formation rates are between a factor of a few and 1 dex, depending on the SED. Radiative processes are responsible for gas heating and photoevaporation, although emission from soft SEDs has minor impacts. These findings have implications for cosmic gas preheating, primordial direct-collapse black holes, the build-up of `cosmic fossils' such as low-mass dwarf galaxies, the role of active galactic nuclei during reionization, the early formation of extended discs and angular-momentum catastrophe.

  4. Is photocleavage of DNA by YOYO-1 using a synchrotron radiation light source sequence dependent?

    DEFF Research Database (Denmark)

    Gilroy, Emma L.; Hoffmann, Søren Vrønning; Jones, Nykola C.;

    2011-01-01

    The photocleavage of double-stranded and single-stranded DNA by the fluorescent dye YOYO-1 was investigated in real time by using the synchrotron radiation light source ASTRID (ISA, Denmark) both to initiate the reaction and to monitor its progress using Couette flow linear dichroism (LD) through......The photocleavage of double-stranded and single-stranded DNA by the fluorescent dye YOYO-1 was investigated in real time by using the synchrotron radiation light source ASTRID (ISA, Denmark) both to initiate the reaction and to monitor its progress using Couette flow linear dichroism (LD...

  5. A Response of coaxial Ge (Li) detector to the extended source of gamma radiation

    International Nuclear Information System (INIS)

    In measurements of the absolute source strength of extended source of γ radiation, two main limitations on the accuracy are dues to the difficulties in accounting for the self-absorption in the source and for geometrical dependence of detector efficiency. Two problems were separated by introduction of the average only energy dependent efficiency, which lends itself to calculational and experimental determination (to be reported), and the response of coaxial Ge(Li) detector to cylindrical extended source with self-absorption has been developed here to a reduced analytical form convenient gu numerical calculations. (author)

  6. Sources and effects of ionizing radiation. UNSCEAR 2000 report to the General Assembly, with scientific annexes. Volume II: Effects

    International Nuclear Information System (INIS)

    Over the past few years the United Nations Scientific Committee on the effects of Atomic Radiation has undertaken a broad review of the sources and effects of ionizing radiation. In the present report, the Committee, drawing on the main conclusions of its scientific assessment summarizes the developments in radiation science in the years leading up to the next millennium. It covers the following: the effects of radiation exposure; levels of radiation exposure; radiological consequences of the Chernobyl accident; sources of radiation exposure including natural exposures, man-made environmental exposures, medical and occupational exposures; radiation associated cancer. This volume includes five Annexes covering: DNA repair and mutagenesis; biological effects at low radiation doses; combined effects of radiation and other agents; epidemiological evaluation of radiation-induced cancer and exposure effects of the Chernobyl accident

  7. Accelerator-driven X-ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Dinh Cong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-09

    After an introduction which mentions x-ray tubes and storage rings and gives a brief review of special relativity, the subject is treated under the following topics and subtopics: synchrotron radiation (bending magnet radiation, wiggler radiation, undulator radiation, brightness and brilliance definition, synchrotron radiation facilities), x-ray free-electron lasers (linac-driven X-ray FEL, FEL interactions, self-amplified spontaneous emission (SASE), SASE self-seeding, fourth-generation light source facilities), and other X-ray sources (energy recovery linacs, Inverse Compton scattering, laser wakefield accelerator driven X-ray sources. In summary, accelerator-based light sources cover the entire electromagnetic spectrum. Synchrotron radiation (bending magnet, wiggler and undulator radiation) has unique properties that can be tailored to the users’ needs: bending magnet and wiggler radiation is broadband, undulator radiation has narrow spectral lines. X-ray FELs are the brightest coherent X-ray sources with high photon flux, femtosecond pulses, full transverse coherence, partial temporal coherence (SASE), and narrow spectral lines with seeding techniques. New developments in electron accelerators and radiation production can potentially lead to more compact sources of coherent X-rays.

  8. Brilliant radiation sources by laser-plasma accelerators and optical undulators

    Energy Technology Data Exchange (ETDEWEB)

    Debus, Alexander

    2012-09-06

    This thesis investigates the use of high-power lasers for synchrotron radiation sources with high brilliance, from the EUV to the hard X-ray spectral range. Hereby lasers accelerate electrons by laser-wakefield acceleration (LWFA), act as optical undulators, or both. Experimental evidence shows for the first time that LWFA electron bunches are shorter than the driving laser and have a length scale comparable to the plasma wavelength. Furthermore, a first proof of principle experiment demonstrates that LWFA electrons can be exploited to generate undulator radiation. Building upon these experimental findings, as well as extensive numerical simulations of Thomson scattering, the theoretical foundations of a novel interaction geometry for laser-matter interaction are developed. This new method is very general and when tailored towards relativistically moving targets not being limited by the focusability (Rayleigh length) of the laser, while it does not require a waveguide. In a theoretical investigation of Thomson scattering, the optical analogue of undulator radiation, the limits of Thomson sources in scaling towards higher peak brilliances are highlighted. This leads to a novel method for generating brilliant, highly tunable X-ray sources, which is highly energy efficient by circumventing the laser Rayleigh limit through a novel traveling-wave Thomson scattering (TWTS) geometry. This new method suggests increases in X-ray photon yields of 2-3 orders of magnitudes using existing lasers and a way towards efficient, optical undulators to drive a free-electron laser. The results presented here extend far beyond the scope of this work. The possibility to use lasers as particle accelerators, as well as optical undulators, leads to very compact and energy efficient synchrotron sources. The resulting monoenergetic radiation of high brilliance in a range from extreme ultraviolet (EUV) to hard X-ray radiation is of fundamental importance for basic research, medical

  9. Brilliant radiation sources by laser-plasma accelerators and optical undulators

    International Nuclear Information System (INIS)

    This thesis investigates the use of high-power lasers for synchrotron radiation sources with high brilliance, from the EUV to the hard X-ray spectral range. Hereby lasers accelerate electrons by laser-wakefield acceleration (LWFA), act as optical undulators, or both. Experimental evidence shows for the first time that LWFA electron bunches are shorter than the driving laser and have a length scale comparable to the plasma wavelength. Furthermore, a first proof of principle experiment demonstrates that LWFA electrons can be exploited to generate undulator radiation. Building upon these experimental findings, as well as extensive numerical simulations of Thomson scattering, the theoretical foundations of a novel interaction geometry for laser-matter interaction are developed. This new method is very general and when tailored towards relativistically moving targets not being limited by the focusability (Rayleigh length) of the laser, while it does not require a waveguide. In a theoretical investigation of Thomson scattering, the optical analogue of undulator radiation, the limits of Thomson sources in scaling towards higher peak brilliances are highlighted. This leads to a novel method for generating brilliant, highly tunable X-ray sources, which is highly energy efficient by circumventing the laser Rayleigh limit through a novel traveling-wave Thomson scattering (TWTS) geometry. This new method suggests increases in X-ray photon yields of 2-3 orders of magnitudes using existing lasers and a way towards efficient, optical undulators to drive a free-electron laser. The results presented here extend far beyond the scope of this work. The possibility to use lasers as particle accelerators, as well as optical undulators, leads to very compact and energy efficient synchrotron sources. The resulting monoenergetic radiation of high brilliance in a range from extreme ultraviolet (EUV) to hard X-ray radiation is of fundamental importance for basic research, medical

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

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, Clell J. Jr. [Los Alamos National Laboratory

    2012-04-26

    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 description 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 utility can

  11. Quantifying the contributions of individual NOx sources to the trend in ozone radiative forcing

    OpenAIRE

    Dahlmann, Katrin; Grewe, Volker; Ponater, Michael; Matthes, Sigrun

    2011-01-01

    Source attribution of ozone radiative forcing (RF) is a prerequisite for developing adequate emission mitigation strategies with regards to climate impact. Decadal means of ozone fields from transient climate-chemistry simulations (1960-2019) are analysed and the temporal development of ozone RF resulting from individual NOx sources, e.g. road traffic, industry and air traffic, is investigated. We calculated an ozone production efficiency which is mainly dependent on the altitude of NOx emiss...

  12. Effects of various radiation source characteristics on shielding requirements at the potential Yucca Mountain repository

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.W.; Miller, D.D. [Bechtel National, Inc., San Francisco, CA (United States); Hill, R.R. [Sandia National Labs., Albuquerque, NM (United States)

    1992-02-01

    This radiation shielding study provides dose rate information that can be used to estimate required shielding thicknesses for different repository configurations, including various hot cells and vaults in the waste-handling building, the boreholes in the underground emplacement area, and the transfer casks. The study determines gamma and neutron source strengths for various waste types and source geometries representative of conditions at the repository and determines dose rates as a function of shielding thickness for selected materials.

  13. Linear-accelerator-based stereotactic irradiation for metastatic brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Takemoto, Mitsuhiro; Katsui, Kuniaki; Yoshida, Atsushi [Okayama Univ. (Japan). School of Medicine] [and others

    2003-05-01

    To assess the safety and availability of stereotactic radiotherapy (SRT) for metastatic brain tumors, we reviewed 54 consecutive cases with a total of 118 brain metastases treated with linear-accelerator-based stereotactic irradiation (STI). Nineteen patients with a total of 27 brain tumors that were larger than 3 cm or close to critical normal tissues were treated with SRT. The marginal dose of SRT was 15-21 Gy (median 21 Gy) in 3 fractions for 3 days. The median marginal dose of stereotactic radiosurgery (SRS) was 20 Gy. Effective rates of imaging studies were 72.7% and 94.4%, and those of clinical symptoms were 46.7% and 55.6% for SRT and SRS, respectively. One-year and two-year survival rates of SRT were 40.9% and 17.6%, respectively, and the median follow-up period was 6.4 months. The one-year survival rate of SRS was 32.7%, with a median follow-up of 4.6 months. Fourteen cases (7 cases each) had recurrent tumors at STI sites. Early complications were observed in one case of SRT and 8 cases of SRS, and late complications occurred in 3 cases of SRS. There were no significant differences among effective rates, survival rates, median follow-up times, recurrence rates, and complications between SRT and SRS. We concluded that SRT is a safe, effective therapy for large or eloquent area metastases. (author)

  14. A Tandem-electrostatic-quadrupole for accelerator-based BNCT

    International Nuclear Information System (INIS)

    A project to develop a Tandem-electrostatic-quadrupole (TESQ) accelerator for accelerator-based boron neutron capture therapy (AB-BNCT) is described. A folded Tandem, with 1.25 MV terminal voltage, combined with an electrostatic quadrupole (ESQ) chain is being proposed. The project goal is a machine capable of delivering 30 mA of 2.5 MeV protons to be used in conjunction with a neutron production target based on the 7Li(p, n)7Be reaction slightly beyond its resonance at 2.25 MeV. This machine is conceptually shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the 7Li(p, n)7Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. This electrostatic machine is the technologically simplest and cheapest solution for optimized AB-BNCT

  15. Tandem-ESQ for accelerator-based BNCT

    International Nuclear Information System (INIS)

    A project to develop a Tandem-ElectroStatic-Quadrupole (TESQ) accelerator for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) is described. A folded tandem, with 1.25 MV terminal voltage, combined with an ElectroStatic Quadrupole (ESQ) chain is being proposed. The project goal is a machine capable of delivering 30 mA of 2.5 MeV protons to be used in conjunction with a neutron production target based on the 7Li(p,n)7Be reaction beyond its resonance at 2.25 MeV. This machine is conceptually shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the '7Li(p,n)7Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. This electrostatic machine is the technologically simplest and cheapest solution for optimized AB-BNCT. (author)

  16. SiC detectors for radiation sources characterization and fast plasma diagnostic

    Science.gov (United States)

    Cannavò, A.; Torrisi, L.

    2016-09-01

    Semiconductor detectors based on SiC have been investigated to characterize the radiations (photons and particles) emitted from different sources, such as radioactive sources, electron guns, X-ray tubes and laser-generated plasmas. Detectors show high response velocity, low leakage current, high energy gap and high radiation hardness. Their high detection efficiency permits to use the detectors in spectroscopic mode and in time-of-flight (TOF) approach, generally employed to monitor low and high radiation fluxes, respectively. Using the laser start signal, they permit to study the properties of the generated plasma in vacuum by measuring accurately the particle velocity and energy using pulsed lasers at low and high intensities. Possible applications will be reported and discussed.

  17. Theoretical study on the carbon nanotube used ashard x—radiation source

    Institute of Scientific and Technical Information of China (English)

    LuJing-Han; QinXi-Jun

    1998-01-01

    Calculations and analyses are made on the interaction between the carbon nanotube and the incident positron of high energy.The results obtained show that it is possible to use carbon nanotube as hard X-radiation source with high intensity and good monochromaticity.

  18. POPULATION RADIATION PROTECTION PROVIDING UNDER THE INFLUENCE OF NATURAL IONIZING IRRADIATION SOURCES

    Directory of Open Access Journals (Sweden)

    E. G. Stepanov

    2015-01-01

    Full Text Available An article presents the modern problems of population radiation protection inBashkortostanRepublic. The main natural ionizing irradiation sources are identified and their contribution to the total exposure dose of the BashkortostanRepublicpopulation is analyzed. The types of the main natural ionizing irradiation sources are identified, as well as the ways of their intake and the methods of their influence. The results of laboratory studies are presented for the radon equivalent equilibrium volumetric activity, for the average gamma radiation dose rate in dwellings, for the investigations of gross alpha and gross beta activity in drinking water and open water sourcesBashkortostanRepublic. The article underlines the main problems of the radiation situation in the new construction. The main preventive measures are pointed out for the radiation protection of the buildings under construction improving. The article also presents an analysis of the results of activities of the Administration of Rospotrebnadzor in theBashkortostanRepublicfor the reducing of the levels of the Republican population exposure from the natural irradiation sources.

  19. Nanoscale displacement of the image of an atomic source of radiation

    Institute of Scientific and Technical Information of China (English)

    Xin Li; Jie Shu; Henk F. Arnoldus

    2009-01-01

    Light emitted by an atomic source of radiation appears to travel along a straight line (ray) from the location of the source to the observer in the far field. However, when the energy flow pattern of the radiation is resolved with an accuracy better than an optical wavelength, it turns out that the field lines are usually curved. We consider electric dipole radiation, a prime example of which is the radiation emitted by an atom during an electronic transition, and we show that the field lines of energy flow are in general curves. Near the location of the dipole, the field lines exhibit a vortex structure, and in the far field they approach a straight line. The spatial extension of the vortex in the optical near field is of nanoscale dimension. Due to the rotation of the field lines near the source, the asymptotic limit of a field line is not exactly in the radially outward direction and as a consequence, the image in the far field is slightly shifted. This sub-wavelength displacement of the image of the source should be amenable to experimental observation with contemporary nanoscale-precision techniques.

  20. Coherent Sources of XUV Radiation Soft X-Ray Lasers and High-Order Harmonic Generation

    CERN Document Server

    Jaeglé, Pierre

    2006-01-01

    Extreme ultraviolet radiation, also referred to as soft X-rays or XUV, offers very special optical properties. The X-UV refractive index of matter is such that normal reflection cannot take place on polished surfaces whereas beam transmission through one micrometer of almost all materials reduces to zero. Therefore, it has long been a difficult task to imagine and to implement devices designed for complex optics experiments in this wavelength range. Thanks to new sources of coherent radiation - XUV-lasers and High Order Harmonics - the use of XUV radiation, for interferometry, holography, diffractive optics, non-linear radiation-matter interaction, time-resolved study of fast and ultrafast phenomena and many other applications, including medical sciences, is ubiquitous.

  1. Management of ionizing radiation sources in university, medical and industrial environments; Gestion des sources ionisantes en milieux universitaire, medical et industriel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This conference treats several subjects relative to the use of radioactive sources. The first session comprises three articles about ionizing sources and regulation. The second session, with three articles, tackles the question of radiation protection in the use of sources in industrial field. The third session, four articles, treats the same question but in the medicine and university media. The fourth session (three articles) is devoted to the organisation of radiation protection in the case of accidents. The fifth session concerns the management of spent sources (three articles). The sixth session studies the radiation protection of sources in Europe. The seventh and final session ends with the part and coordination of actors in radiation protection in the sources management (three articles). (N.C.)

  2. Beam conditions for radiation generated by an electromagnetic Hermite-Gaussian model source

    Institute of Scientific and Technical Information of China (English)

    LI Jia; XIN Yu; CHEN Yan-ru

    2011-01-01

    @@ Within the framework of the correlation theory of electromagnetic laser beams, the far field cross-spectral density matrix of the light radiated from an electromagnetic Hermite-Gaussian model source is derived.By utilizing the convergence property of Hermite polynomials, the conditions of the matrices for the source to generate an electromagnetic Hermite-Gaussian beam are obtained.Furthermore, in order to generate a scalar Hermite-Gaussian model beam, it is required that the source should be locally rather coherent in the spatial domain.

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

    Science.gov (United States)

    Sasaki, Akira; Sunahara, Atsushi; Furukawa, Hiroyuki; Nishihara, Katsunobu; Fujioka, Shinsuke; Nishikawa, Takeshi; Koike, Fumihiro; Ohashi, Hayato; Tanuma, Hajime

    2010-06-01

    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 Sn5+ to Sn13+ are investigated, because of their importance for determining the 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 1018 cm-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.

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

    International Nuclear Information System (INIS)

    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 Sn5+ to Sn13+ are investigated, because of their importance for determining the 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 1018 cm-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.

  5. An analysis on international trends of radiation application and security of radioactive sources

    International Nuclear Information System (INIS)

    Radiation technologies are being utilized in a wide range of daily modern life and provide the public with valuable benefits through applications in fields of medical, industrial, agricultural, and science and engineering research. On the other hand, there is a high possibility that radioactive materials could be used for potentially malevolent purposes such as dirty bombs. International community, therefore, has made efforts to improve security of radioactive sources for protecting the public from radiological terrorism. This study investigated current status of radiation technologies and radioactive sources which could be used by radiological dispersal devices. This paper also reviewed the possibility of radiological weapon attacks, international trends and our methods to enhance security of radioactive sources

  6. Blind source separation of ship-radiated noise based on generalized Gaussian model

    Institute of Scientific and Technical Information of China (English)

    Kong Wei; Yang Bin

    2006-01-01

    When the distribution of the sources cannot be estimated accurately, the ICA algorithms failed to separate the mixtures blindly. The generalized Gaussian model (GGM) is presented in ICA algorithm since it can model nonGaussian statistical structure of different source signals easily. By inferring only one parameter, a wide class of statistical distributions can be characterized. By using maximum likelihood (ML) approach and natural gradient descent, the learning rules of blind source separation (BSS) based on GGM are presented. The experiment of the ship-radiated noise demonstrates that the GGM can model the distributions of the ship-radiated noise and sea noise efficiently, and the learning rules based on GGM gives more successful separation results after comparing it with several conventional methods such as high order cumulants and Gaussian mixture density function.

  7. Dosimetric comparison of linear accelerator-based stereotactic radiosurgery systems

    Directory of Open Access Journals (Sweden)

    Sharma S

    2007-01-01

    Full Text Available Stereotactic radiosurgery (SRS is a special radiotherapy technique used to irradiate intracranial lesions by 3-D arrangements of narrow photon beams eliminating the needs of invasive surgery. Three different tertiary collimators, namely BrainLab and Radionics circular cones and BrainLab micro multileaf collimator (mMLC, are used for linear accelerator-based SRS systems (X-Knife. Output factor (St, tissue maximum ratio (TMR and off axis ratio (OAR of these three SRS systems were measured using CC01 (Scanditronix/ Welhofer and Pinpoint (PTW cylindrical and Markus plane parallel ionization chambers as well as TLD and radiochromic film. Measurement results of CC01 and Pinpoint chambers were very close to each other which indicate that further reduction in volume and physical dimensions of cylindrical ionization chamber is not necessary for SRS/SRT dosimetry. Output factors of BrainLab and Radionics SRS cones were very close to each other while output factors of equivalent diameter mMLC field were different from SRS circular cones. TMR of the three SRS systems compared were very close to one another. OAR of Radionics cone and BrainLab mMLC were very close to each other, within 2%. However, OARs of BrainLab cone were found comparable to OARs of Radionics cone and BrainLab mMLC within maximum variation of 4%. In addition, user-measured similar data of other three mMLC X-Knives were compared with the mMLC X-Knife data measured in this work and found comparable. The concept of switching over to mMLC-based SRS/SRT is thus validated from dosimetric characteristics as well.

  8. Regulatory infrastructure for the control of radiation sources in the Africa region: Status, needs and programmes

    International Nuclear Information System (INIS)

    In recent years, several African countries have taken steps towards creating or strengthening legal, administrative and technical mechanisms for the regulation and control of peaceful uses of nuclear technology, and towards improving the effectiveness and sustainability of radiation protection measures based on international standards. This stems from a growing awareness that a proper national infrastructure is a prerequisite for the implementation of safety standards to achieve and maintain the desired level of protection and safety, particularly in such sectors as public health and industry. Also, other issues of global and regional interest, such as the control of radiation sources, including the handling of hazardous waste, and response capabilities in the case of a radiological emergency, have contributed to a better perception of risks associated with deficiencies in or lack of adequate national radiation protection control mechanisms. Too often, however, this awareness has not been matched with adequate progress in the establishment of a regulatory framework for the control of radiation sources. This paper presents a summary of the current status of radiation protection infrastructure in all African Member States. On a background of still existing weaknesses and challenges, an overview of the Agency's response to assistance needs and programmes in this field is discussed. (author)

  9. Permissible dose from external sources of ionizing radiation. Recommendations of the National Committee on Radiation Protection. Handbook 59

    International Nuclear Information System (INIS)

    The Advisory Committee on X-ray and Radium Protection was formed in 1929 upon the recommendation of the International Commission on Radiological Protection, under the sponsorship of the National Bureau of Standards, and with the cooperation of the leading radiological organizations. The small committee functioned effectively until the advent of atomic energy, which introduced a large number of new and serious problems in the field of radiation protection. The present report deals primarily with the protection of persons occupationally exposed to ionizing radiation from external sources. An attempt has been made to cover most of the situations encountered in practice. However, it has not always been possible to make recommendations in quantitative terms. In such cases the recommendations are intended to serve as practical guides. The recommendations are based on presently available information and cannot be regarded as permanent. For this reason and on general grounds it is strongly recommended that exposure to radiation be kept at the lowest practicable level in all cases

  10. Compact narrow-band THz radiation source based on photocathode rf gun

    International Nuclear Information System (INIS)

    Narrow-band THz coherent Cherenkov radiation can be driven by a subpicosecond electron bunch traveling along the axis of a hollow cylindrical dielectric-lined waveguide. We present a scheme of compact THz radiation source based on the photocathode rf gun. On the basis of our analytic result, the subpicosecond electron bunch with high charge (800 pC) can be generated directly in the photocathode rf gun. According to the analytical and simulated results, a narrow emission spectrum peaked at 0.24 THz with 2 megawatt (MW) peak power is expected to gain in the proposed scheme (the length of the facility is about 1.2 m). (authors)

  11. Definition of loss-of-coolant accident radiation source. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    1978-02-01

    Meaningful qualification testing of nuclear reactor components requires a knowledge of the radiation fields expected in a loss-of-coolant accident (LOCA). The overall objective of this program is to define the LOCA source terms and compare these with the output of various simulators employed for radiation qualification testing. The basis for comparison will be the energy deposition in a model reactor component. The results of the calculations are presented and some interpretation of the results given. The energy release rates and spectra were validated by comparison with other calculations using different codes since experimental data appropriate to these calculations do not exist.

  12. Definition of loss-of-coolant accident radiation source: summary and conclusions. [BWR; PWR

    Energy Technology Data Exchange (ETDEWEB)

    Bonzon, L.L.; Lurie, N.A.; Houston, D.H.; Naber, J.A.

    1978-05-01

    The radiation energy release rates and spectra corresponding to those sources specified in USNRC Regulatory Guide 1.89 for the radiation qualification of Class 1E equipment were calculated. The effects of several parameters (some not specific in the Guide), such as reactor fuel composition, operating duration and power level, and treatment of progeny, are evaluated. The results are presented as time-dependent beta and gamma-ray energy release rates and spectra which are fundamental quantities that are not specific to a plant design but are generally applicable to any nuclear power station.

  13. Coupling aerosol-cloud-radiative processes in the WRF-Chem model: investigating the radiative impact of elevated point sources

    Directory of Open Access Journals (Sweden)

    E. G. Chapman

    2008-08-01

    Full Text Available The local and regional influence of elevated point sources on summertime aerosol forcing and cloud-aerosol interactions in northeastern North America was investigated using the WRF-Chem community model. The direct effects of aerosols on incoming solar radiation were simulated using existing modules to relate aerosol sizes and chemical composition to aerosol optical properties. Indirect effects were simulated by adding a prognostic treatment of cloud droplet number and adding modules that activate aerosol particles to form cloud droplets, simulate aqueous-phase chemistry, and tie a two-moment treatment of cloud water (cloud water mass and cloud droplet number to an existing radiation scheme. Fully interactive feedbacks thus were created within the modified model, with aerosols affecting cloud droplet number and cloud radiative properties, and clouds altering aerosol size and composition via aqueous processes, wet scavenging, and gas-phase-related photolytic processes. Comparisons of a baseline simulation with observations show that the model captured the general temporal cycle of aerosol optical depths (AODs and produced clouds of comparable thickness to observations at approximately the proper times and places. The model overpredicted SO2 mixing ratios and PM2.5 mass, but reproduced the range of observed SO2 to sulfate aerosol ratios, suggesting that atmospheric oxidation processes leading to aerosol sulfate formation are captured in the model. The baseline simulation was compared to a sensitivity simulation in which all emissions at model levels above the surface layer were set to zero, thus removing stack emissions. Instantaneous, site-specific differences for aerosol and cloud related properties between the two simulations could be quite large, as removing above-surface emission sources influenced when and where clouds formed within the modeling domain. When summed spatially over the finest resolution model

  14. Bernoulli particle filter with observer altitude for maritime radiation source tracking in the presence of measurement uncertainty

    Institute of Scientific and Technical Information of China (English)

    Luo Xiaobo; Fan Hongqi; Song Zhiyong; Fu Qiang

    2013-01-01

    For maritime radiation source target tracking in particular electronic counter measures (ECM) environment, there exists two main problems which can deteriorate the tracking perfor-mance of traditional approaches. The first problem is the poor observability of the radiation source. The second one is the measurement uncertainty which includes the uncertainty of the target appear-ing/disappearing and the detection uncertainty (false and missed detections). A novel approach is proposed in this paper for tracking maritime radiation source in the presence of measurement uncertainty. To solve the poor observability of maritime radiation source target, using the radiation source motion restriction, the observer altitude information is incorporated into the bearings-only tracking (BOT) method to obtain the unique target localization. Then the two uncertainties in the ECM environment are modeled by the random finite set (RFS) theory and the Bernoulli filtering method with the observer altitude is adopted to solve the tracking problem of maritime radiation source in such context. Simulation experiments verify the validity of the proposed approach for tracking maritime radiation source, and also demonstrate the superiority of the method compared with the traditional integrated probabilistic data association (IPDA) method. The tracking perfor-mance under different conditions, particularly those involving different duration of radiation source opening and switching-off, indicates that the method to solve our problem is robust and effective.

  15. Study on External Exposure Doses Received by the Cuban Population from Environmental Radiation Sources

    International Nuclear Information System (INIS)

    The results are described of the study carried out with the aim of assessing doses received by the Cuban population due to the external exposure to environmental radiation sources. Contributions of cosmic radiation's ionising and indirectly ionising components to these doses, as well as the fraction resulting from terrestrial radiation, were also assessed as part of this study. Measurements made enabled us to estimate representative effective average doses received by the Cuban population from external exposure to cosmic and terrestrial radiation. Both outdoor and indoor permanency were taken into account for this estimate as well as the distribution of the Cuban population by altitude. The average representative dose due to cosmic radiation was estimated to be 298 ± 17 μSv per year, while the dose received by terrestrial radiation represented 180 ± 14 μSv per year, for a total annual dose of 78 ± 20 μSv. These values are within the range of those reported throughout the world by other authors. (author)

  16. Sources and effects of ionizing radiation. UNSCEAR 1994 report to the General Assembly, with scientific annexes

    International Nuclear Information System (INIS)

    During the last few years the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has undertaken a broad review of the sources and effects of ionizing radiation. Nine scientific annexes on particular subjects were issued in the UNSCEAR 1993 Report. Two further annexes have been completed, and these comprise the UNSCEAR 1994 Report. This is the twelfth substantive Report of the Committee, informing the General Assembly and the scientific and world community of its latest assessments. The two reports, 1993 and 1994, are complementary and provide a coherent summary of the Committee's findings and programme of work. The Committee considers in this report the effects of ionizing radiation on plants and animals in the environment. These effects have not previously been addressed directly by the Committee. The emphasis of past assessments has been on determining the effects of radiation on human health. With the increasing interest around the world in nurturing the environment and concerns about possible detrimental effects of radiation, the time is appropriate for the Committee to provide a summary of the effects of radiation on the environment. Refs, figs, tabs

  17. Protection and safety of the application of radiation sources in medicine

    International Nuclear Information System (INIS)

    Creating working conditions that are safe and do not endanger health in connection with the application of ionizing radiation in health care means quite complicated tasks and obligations to the employees whose main orders concerning the application of radiation sources and radiation protection are determined in the Workplace Radiation Protection Regulation. At the same time, almost all internal regulations of health and security at work have a chapter on radiation (regulations of occupational safety, fire protection, etc.) The well-co-ordinated work of several experts and special fields is needed for taking protective measures and a far-reaching authority and supervising system takes care of keeping the rules and making the realization easier. Naturally, what has been written down here is only of summarising character. Its aim is to call the attention to the requirements in a form within the understanding of everybody with a high-level knowledge of the given technology and the professional requirements of radiation protection, and the widespread application of the legal and standard rules redownloaded in this writing are necessary for realising complex protection. (author)

  18. A critical experimental test of synchrotron radiation theory with 3rd generation light source

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2016-05-15

    A recent ''beam splitting'' experiment at LCLS apparently demonstrated that after a microbunched electron beam is kicked on a large angle compared to the divergence of the FEL radiation, the microbunching wave front is readjusted along the new direction of motion of the kicked beam. Therefore, coherent radiation from an undulator placed after the kicker is emitted along the kicked direction without suppression. This strong emission of coherent undulator radiation in the kicked direction cannot be explained in the framework of conventional synchrotron radiation theory. In a previous paper we explained this puzzle. We demonstrated that, in accelerator physics, the coupling of fields and particles is based, on the one hand, on the use of results from particle dynamics treated according to the absolute time convention and, on the other hand, on the use of Maxwell equations treated according to the standard (Einstein) synchronization convention. Here lies the misconception which led to the strong qualitative disagreement between theory and experiment. After the ''beam splitting'' experiment at LCLS, it became clear that the conventional theory of synchrotron radiation cannot ensure the correct description of coherent and spontaneous emission from a kicked electron beam, nor the emission from a beam with finite angular divergence, in an undulator or a bending magnet. However, this result requires further experimental confirmation. In this publication we propose an uncomplicated and inexpensive experiment to test synchrotron radiation theory at 3rd generation light sources.

  19. Regulatory control of radiation sources and radioactive materials: The UK position

    International Nuclear Information System (INIS)

    The paper presents the organizations involved in the regulation of the safety of radiation sources and the security of radioactive materials across the UK. The safety of radiation sources is within the regulatory remit of the Health and Safety Executive, under the Health and safety of Work Act 1974 and associated regulations. Any employer using radiation sources has a statutory duty to comply with this legislation, thereby protecting workers and the public from undue risk. From a radioactive waste management perspective, the storage and use of radioactive materials and the accumulation and disposal of radioactive waste are regulated by the environment agencies of England and Wales, Scotland, and Northern Ireland, under the Radioactive Substances Act 1993. Special regulatory arrangements apply to nuclear sites, such as power stations and fuel cycle plants, and some additional bodies are involved in the regulation of the security of fissile materials. An explanation is given in the paper as to how these organizations to work together to provide a comprehensive and effective regulatory regime. An overview of how these regulators have recently started to work more closely with other enforcement bodies, such as the Police and Customs and Excise is also given, to illustrate the approach that is being applied in the UK to deal with orphan sources and illicit trafficking. (author)

  20. Development of sup 1 sup 9 sup 2 Ir radiation sources for intravascular irradiation

    CERN Document Server

    Kogure, H; Iwamoto, S; Iwata, K; Kawauchi, Y; Nagata, Y; Sorita, T; Suzuki, K

    2003-01-01

    Intravascular brachytherapy is a novel therapy for preventing the restenosis of coronary artery by use of low-dose irradiation. JAERI and Kyoto University have been developing sup 1 sup 9 sup 2 Ir radiation sources by the cooperative research project entitled as 'The research on safety and effectiveness of the intravascular brachytherapy for preventing restenosis of the coronary artery disease' since 1998. The radiation source was introduced into the stenosis through a catheter (a guide-tube to insert directly into vascular) to irradiate the diseased part. Ten sup 1 sup 9 sup 2 Ir seed sources (phi 0.4 mm x 2.5 mm) were positioned between nylon spacers (phi 0.3 mm x 1.0 mm) in a flexible covering tube and the tube was plugged with a core-wire; the tube was shrunk to fix the inside materials and the size is 0.46 mm in diameter and 3 m in length. The physically optimal design was determined to insert the radiation source easily into vascular and to get the dose uniformity in the diseased part. The production me...

  1. Transverse coherence properties of X-ray beams in third-generation synchrotron radiation sources

    CERN Document Server

    Geloni, Gianluca; Schneidmiller, Evgeni; Yurkov, Mikhail

    2008-01-01

    This article describes a complete theory of spatial coherence for undulator radiation sources. Current estimations of coherence properties often assume that undulator sources are quasi-homogeneous, like thermal sources, and rely on the application of the van Cittert-Zernike theorem for calculating the degree of transverse coherence. Such assumption is not adequate when treating third generation light sources, because the vertical(geometrical) emittance of the electron beam is comparable or even much smaller than the radiation wavelength in a very wide spectral interval that spans over four orders of magnitude (from 0.1 Angstrom up to 10^3 Angstrom). Sometimes, the so-called Gaussian-Schell model, that is widely used in statistical optics in the description of partially-coherent sources, is applied as an alternative to the quasi-homogeneous model. However, as we will demonstrate, this model fails to properly describe coherent properties of X-ray beams from non-homogeneous undulator sources. As a result, a more...

  2. Gravitational Radiation from Post-Newtonian Sources and Inspiralling Compact Binaries

    Directory of Open Access Journals (Sweden)

    Blanchet Luc

    2006-06-01

    Full Text Available The article reviews the current status of a theoretical approach to the problem of the emission of gravitational waves by isolated systems in the context of general relativity. Part A of the article deals with general post-Newtonian sources. The exterior field of the source is investigated by means of a combination of analytic post-Minkowskian and multipolar approximations. The physical observables in the far-zone of the source are described by a specific set of radiative multipole moments. By matching the exterior solution to the metric of the post-Newtonian source in the near-zone we obtain the explicit expressions of the source multipole moments. The relationships between the radiative and source moments involve many non-linear multipole interactions, among them those associated with the tails (and tails-of-tails of gravitational waves. Part B of the article is devoted to the application to compact binary systems. We present the equations of binary motion, and the associated Lagrangian and Hamiltonian, at the third post-Newtonian (3PN order beyond the Newtonian acceleration. The gravitational-wave energy flux, taking consistently into account the relativistic corrections in the binary moments as well as the various tail effects, is derived through 3.5PN order with respect to the quadrupole formalism. The binary's orbital phase, whose prior knowledge is crucial for searching and analyzing the signals from inspiralling compact binaries, is deduced from an energy balance argument.

  3. Accelerator-based neutron tomography cooperating with X-ray radiography

    International Nuclear Information System (INIS)

    Neutron resonance absorption spectroscopy (N-RAS) using a pulsed neutron source can be applied to time-of-flight (TOF) radiography, and the obtained parameters from the peak shape analysis can be reconstructed as the tomograms of nuclide distributions using computed tomography (CT). The problem is that the available spatial resolution is not sufficient for radiography imaging. In this study, we combined neutron and X-ray radiographies to improve the quantitative reconstruction of the neutron tomogram. The accelerator-based neutron source emits X-rays (or gamma-rays) at the same time the neutron pulse is emitted. We utilized the X-ray beam from the neutron source to obtain X-ray radiogram on the same beam line with neutron radiography and then reconstructed the neutron tomogram quantitatively with the help of a detailed sample internal structure obtained from the X-ray radiogram. We calculated the nuclide number density distribution tomogram using a statistical reconstruction procedure, which was easy to include in the structure model during the reconstruction. The obtained result of nuclide number density distribution showed good coincidence with the original object number density.

  4. A Study on the Radiation Source Effect to the Radiation Shielding Analysis for a Spent-Fuel Cask Design with Burnup-Credit

    International Nuclear Information System (INIS)

    The radiation shielding analysis for a Burnup-credit (BUC) cask designed under the management of Korea Radioactive Waste Management Corporation (KRMC) was performed to examine the contribution of each radiation source affecting dose rate distribution around the cask. Various radiation sources, which contain neutron and gamma-ray sources placed in active fuel region and the activation source, and imaginary nuclear fuel were all considered in the MCNP calculation model to realistically simulate the actual situations. It was found that the maximum external and surface dose rates of the spent fuel cask were satisfied with the domestic standards both in normal and accident conditions. In normal condition, the radiation dose rate distribution around the cask was mainly influenced by activation source (60 Co radioisotope); in another case, the neutron emitted in active fuel region contributed about 90% to external dose rate at 1m distance from side surface of the cask. Besides, the contribution level of activation source was dramatically increased to the dose rates in top and bottom regions of the cask. From this study, it was recognized that the detailed investigation on the radiation sources should be performed conservatively and accurately in the process of radiation shielding analysis for a BUC cask.

  5. Saturn Neutron Exosphere as Source for Inner and Innermost Radiation Belts

    Science.gov (United States)

    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 (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 ring surfaces, are additional sources of protons via ionization and charge exchange from breakup of

  6. Advisory Committee on human radiation experiments. Supplemental Volume 2a, Sources and documentation appendices. Final report

    International Nuclear Information System (INIS)

    This large document provides a catalog of the location of large numbers of reports pertaining to the charge of the Presidential Advisory Committee on Human Radiation Research and is arranged as a series of appendices. Titles of the appendices are Appendix A- Records at the Washington National Records Center Reviewed in Whole or Part by DoD Personnel or Advisory Committee Staff; Appendix B- Brief Descriptions of Records Accessions in the Advisory Committee on Human Radiation Experiments (ACHRE) Research Document Collection; Appendix C- Bibliography of Secondary Sources Used by ACHRE; Appendix D- Brief Descriptions of Human Radiation Experiments Identified by ACHRE, and Indexes; Appendix E- Documents Cited in the ACHRE Final Report and other Separately Described Materials from the ACHRE Document Collection; Appendix F- Schedule of Advisory Committee Meetings and Meeting Documentation; and Appendix G- Technology Note

  7. Measurement, analysis and correction of the closed orbit distortion in Indus-2 synchrotron radiation source

    International Nuclear Information System (INIS)

    The paper presents the measurement, analysis and correction of closed orbit distortion (COD) in Indus-2 at 550 MeV injection energy and 2 GeV synchrotron radiation user run energy. The measured COD was analysed and fitted to understand major sources of errors in terms of the effective quadrupole misalignments. The rms COD was corrected down to less than 0.6 mm in both horizontal and vertical planes. A golden orbit was set for the operative synchrotron radiation beamlines. With COD correction, the injection efficiency at 550 MeV was improved by ∼ 8 h. In this paper, the method of global COD correction based on singular value decomposition (SVD) of the orbit response matrix is described. Results for the COD correction in both horizontal and vertical planes at 550 MeV injection energy and at 2 GeV synchrotron radiation user run energy are discussed. (author)

  8. Advisory Committee on human radiation experiments. Supplemental Volume 2a, Sources and documentation appendices. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    This large document provides a catalog of the location of large numbers of reports pertaining to the charge of the Presidential Advisory Committee on Human Radiation Research and is arranged as a series of appendices. Titles of the appendices are Appendix A- Records at the Washington National Records Center Reviewed in Whole or Part by DoD Personnel or Advisory Committee Staff; Appendix B- Brief Descriptions of Records Accessions in the Advisory Committee on Human Radiation Experiments (ACHRE) Research Document Collection; Appendix C- Bibliography of Secondary Sources Used by ACHRE; Appendix D- Brief Descriptions of Human Radiation Experiments Identified by ACHRE, and Indexes; Appendix E- Documents Cited in the ACHRE Final Report and other Separately Described Materials from the ACHRE Document Collection; Appendix F- Schedule of Advisory Committee Meetings and Meeting Documentation; and Appendix G- Technology Note.

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

    Science.gov (United States)

    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.

  10. Radiation exposure modeling for apartment living spaces with multiple radioactive sources.

    Science.gov (United States)

    Hwang, J S; Chan, C C; Wang, J D; Chang, W P

    1998-03-01

    Since late 1992, over 100 building complexes in Taiwan, including both public and private schools, and 1,000 apartments have been identified as emitting elevated levels of gamma-radiation. These high levels of gamma-radiation have been traced to construction steel contaminated with 60Co. Accurate reconstruction of the radiation exposure dosage among residents is complicated by the discovery of multiple radioactive sources within the living spaces and by the lack of comprehensive information about resident life-style and occupancy patterns within these contaminated spaces. The objective of this study was to evaluate the sensitivity of current dose reconstruction approach employed in an epidemiological study for the health effects of these occupants. We apply a statistical method of local smoothing in dose rate estimation and examine factors that are closely associated with radiation exposure from multiple radioactive sources in the apartment. Two examples are used, a simulated measurement in a hypothetical room with three radioactive sources and a real apartment in Ming-Shan Villa, one of the contaminated buildings. The simulated and estimated means are compared along 5-10 selected points of measurement: by local smoothing approach, with the furniture-adjusted space, and with the occupancy time-weighted mean. We found that the local smoothing approach came much closer to theoretical values. The local smoothing approach may serve as a refined method of radiation dose distribution modeling in exposure estimation. Before environmental exposure assessment, "highly occupied zones" (HOZs) in the contaminated spaces must be identified. Estimates of the time spent in these HOZs are essential to obtain accurate dosage values. These results will facilitate a more accurate dose reconstruction in the assessment of residential exposure in apartments with elevated levels of radioactivity.

  11. Radiological impact of natural and artificial sources of ionizing radiation. Report UNSCEAR 2000

    International Nuclear Information System (INIS)

    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was established by the General Assembly in 1995. It has the mandate to assess the levels and effects of ionizing radiation. During the last years UNSCEAR has undertaken a broad review of the natural and artificial sources of ionizing radiation. The results of these evaluations have been presented in a Report to the General Assembly with Scientific Annexes including extensive data for the world community (Report UNSCEAR 2000). The greatest contribution to radiation exposure comes from natural background sources. There are considerable variation in the exposures of the population depending on the altitude and latitude, characteristics of the soil and diet and the construction and ventilation features of houses. The global annual average per caput is 2.4 mSv with typical range 1 to 10 mSv. The next largest component comes from medical radiation examinations and treatments with an annual average of 0.4 mSv ranging from 0.04 to 1.0 mSv depending on the level o f medical care. The man-made practices, activities, and events in which radionuclides are released to the environment are always of much concern, but usually they contribute quite low to radiation exposure to humans. Atmospheric testing caused the greatest releases but nowadays very low residual annual levels of exposures persist (0.005 mSv). Nuclear Power production is responsible for only very low exposure and may reach in the future an average annual level of 0.0002 mSv. (Author)

  12. Passive Lossless Huygens Metasurfaces for Conversion of Arbitrary Source Field to Directive Radiation

    CERN Document Server

    Epstein, Ariel

    2014-01-01

    We present a semi-analytical formulation of the interaction between a given source field and a scalar Huygens metasurface (HMS), a recently introduced promising concept for wavefront manipulation based on a sheet of orthogonal electric and magnetic dipoles. Utilizing the equivalent surface impedance representation of these metasurfaces, we establish that an arbitrary source field can be converted into directive radiation via a passive lossless HMS if two physical conditions are met: local power conservation and local impedance equalization. Expressing the fields via their plane-wave spectrum and harnessing the slowly-varying envelope approximation we obtain semi-analytical formulae for the scattered fields, and prescribe the surface reactance required for the metasurface implementation. The resultant design procedure indicates that the local impedance equalization induces a Fresnel-like reflection, while local power conservation forms a radiating virtual aperture which follows the total excitation field magni...

  13. Gravitational Radiation from Post-Newtonian Sources and Inspiralling Compact Binaries

    CERN Document Server

    Blanchet, Luc

    2013-01-01

    To be observed and analyzed by the network of gravitational wave detectors on ground (LIGO, VIRGO, etc.) and by the future detectors in space (LISA, etc.), inspiralling compact binaries --- binary star systems composed of neutron stars and/or black holes in their late stage of evolution --- require high-accuracy templates predicted by general relativity theory. The gravitational waves emitted by these very relativistic systems can be accurately modelled using a high-order post-Newtonian gravitational wave generation formalism. In this article, we present the current state of the art on post-Newtonian methods as applied to the dynamics and gravitational radiation of general matter sources (including the radiation reaction back onto the source) and inspiralling compact binaries. We describe the post-Newtonian equations of motion, pay attention to the self-field regularizations at work, discuss several notions of innermost circular orbits, estimate the accuracy of the approximation and make a comparison with num...

  14. Tunable THz radiation source from dielectric loaded waveguide excited by nonrelativistic electron bunch trains

    Science.gov (United States)

    Li, Weiwei; He, Zhigang; Lu, Yalin; Huang, Ruixuan; Liu, Weihao; Jia, Qika; Wang, Lin

    2016-10-01

    We propose a novel scheme to generate a tunable narrow-band THz radiation. In this scheme, a train of laser pulses with THz repetition rate is used to drive a photocathode direct current (DC) gun, leading to the emission of a train of electron bunches. The electron bunch train is subsequently accelerated by the gun field and applied to selectively excite one of the modes in the dielectric loaded waveguide (DLW) structure, which is located downstream the DC gun. Thanks to the tunability of the repetition rate of laser pulses and the gun voltage, a tunable narrow-band THz radiation source can be obtained. This proposed source has the advantages of compactness, robustness and relatively high power.

  15. The uses of synchrotron radiation sources for elemental and chemical microanalysis

    Science.gov (United States)

    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.

  16. Identification of radiation induced dark current sources in pinned photodiode CMOS image sensors

    International Nuclear Information System (INIS)

    This paper presents an investigation of Total Ionizing Dose (TID) induced dark current sources in Pinned Photodiodes (PPD) CMOS Image Sensors based on pixel design variations. The influence of several layout parameters is studied. Only one parameter is changed at a time enabling the direct evaluation of its contribution to the observed device degradation. By this approach, the origin of radiation induced dark current in PPD is localized on the pixel layout. The PPD peripheral shallow trench isolation does not seem to play a role in the degradation. The PPD area and a transfer gate contribution independent of the pixel dimensions appear to be the main sources of the TID induced dark current increase. This study also demonstrates that applying a negative voltage on the transfer gate during integration strongly reduces the radiation induced dark current. (authors)

  17. Analysis of internal radiation and radiotoxicity source base on aerosol distribution in RMI

    International Nuclear Information System (INIS)

    Destructive testing of nuclear fuel element during post irradiation examination in radio metallurgy installation may cause air contamination in the working area in the form of radioactive aerosol. Inhalation of the radioactive aerosol by worker will to become internal radiation source. Potential hazard of radioactive particle in the body also depends on the particle size. Analysis of internal radiation source and radiotoxicity showed that in the normal operation only natural radioactive materials are found with high radiotoxicity, i.e. Pb-212 and Ac-228. High deposit in the alveolar instersial (Ai) is 95 % and lower in the bronchial area (BB) is 1 % for particle size 11.7 nm and 350 nm respectively. (author)

  18. X-ray and gamma-ray astronomy. [origins of extraterrestrial radiation sources

    Science.gov (United States)

    1975-01-01

    Accomplishments in the fields of X-ray and gamma ray astronomy are discussed. Data obtained from IMP and OGO satellites are analyzed to determine the sources of interplanetary radiation bursts. The energy spectrum of cosmic gamma ray bursts as observed by IMP-6 is described. The application of cooling blackbody techniques as a method for examining cosmic gamma ray bursts is reported. The experimental results and theoretical interpretation of high energy diffuse gamma rays are investigated. The structure of the SAS-2 satellite is depicted and the accomplishments are examined. Other sources of gamma radiation to include galactic fermi, Cygnus X-1, supernovae, and the planet Jupiter are proposed. Data obtained from the Pioneer 10 space probe are presented in graph form.

  19. Impact of next-generation synchrotron radiation sources on materials research

    CERN Document Server

    Shenoy, G K

    2003-01-01

    Three generations of synchrotron radiation sources have revolutionized our understanding of various correlations in the equilibrium phase of materials through X-ray imaging, spectroscopy and scattering techniques. It is anticipated that new sources based on energy-recovery linacs and X-ray free-electron lasers will deliver X-ray pulses that are below a few-hundred femtoseconds in length and have very high coherence. These sources will extend and broaden our current knowledge of materials science. But more importantly, it is expected that these sources will provide the first glimpse of nonequilibrium processes in materials, including nonthermal melting, metal-insulator transitions involving nonequilibrium phases, laser-induced catalytic oxidation, and determining the structure of imperfect nanoparticles lacking crystalline structure.

  20. Time-resolved X-ray studies using third generation synchrotron radiation sources

    International Nuclear Information System (INIS)

    The third generation, high-brilliance, hard x-ray, synchrotron radiation (SR) sources currently under construction (ESRF at Grenoble, France; APS at Argonne, Illinois; and SPring-8 at Harima, Japan) will usher in a new era of x-ray experimentation for both physical and biological sciences. One of the most exciting areas of experimentation will be the extension of x-ray scattering and diffraction techniques to the study of transient or time-evolving systems. The high repetition rate, short-pulse duration, high brilliance, and variable spectral bandwidth of these sources make them ideal for x-ray time-resolved studies. The temporal properties (bunch length, interpulse period, etc.) of these new sources will be summarized. Finally, the scientific potential and the technological challenges of time-resolved x-ray scattering from these new sources will be described. 13 refs., 4 figs

  1. Multi-pass Accelerator-Recuperator (MARS) as Coherent X-ray Synchrotron Radiation Source

    Science.gov (United States)

    Kulipanov, Gennady; Skrinsky, Alexander; Vinokurov, Nikolai

    2007-01-01

    Creation of a fully spatial coherent 4th generation SR source is possible in case of a shift from the electron storage rings to accelerators with energy recovery. However, in practice, all the projects assume the use of a single-turn version (ERL) compared to our first proposal of 1997 to use a multi-turn accelerator-recuperator (MARS). The purpose of this report is presentation of the modern conception of MARS and comparison of the ERL and MARS based radiation sources from the viewpoint of their realization in practice.

  2. Leakage of an irradiator source: The June 1988 Georgia RSI [Radiation Sterilizers, Inc.] incident

    International Nuclear Information System (INIS)

    On June 6, 1988, operators of a pool irradiator in Decatur, Georgia, were prevented by a safety system from raising sources from the pool. Radiation levels of 60 millirem per hour at the surface of the pool water were found, indicative of a leak of one or more of the 252 Cs-137 source capsules used at the irradiator. A summary of the Incident Evaluation Task Force's First Interim Report has been prepared for person's needing an overview of the incident and lessons learned to date. This report provides a summary of Agreement States' views and recommendations on some of the issues raised by the incident

  3. Ionizing radiation sources: very diversified means, multiple applications and a changing regulatory environment. Conference proceedings

    International Nuclear Information System (INIS)

    This document brings together the available presentations given at the conference organised by the French society of radiation protection about ionizing radiation source means, applications and regulatory environment. Twenty eight presentations (slides) are compiled in this document and deal with: 1 - Overview of sources - some quantitative data from the national inventory of ionizing radiation sources (Yann Billarand, IRSN); 2 - Overview of sources (Jerome Fradin, ASN); 3 - Regulatory framework (Sylvie Rodde, ASN); 4 - Alternatives to Iridium radiography - the case of pressure devices at the manufacturing stage (Henri Walaszek, Cetim; Bruno Kowalski, Welding Institute); 5 - Dosimetric stakes of medical scanner examinations (Jean-Louis Greffe, Charleroi hospital of Medical University); 6 - The removal of ionic smoke detectors (Bruno Charpentier, ASN); 7 - Joint-activity and reciprocal liabilities - Organisation of labour risk prevention in case of companies joint-activity (Paulo Pinto, DGT); 8 - Consideration of gamma-graphic testing in the organization of a unit outage activities (Jean-Gabriel Leonard, EDF); 9 - Radiological risk control at a closed and independent work field (Stephane Sartelet, Areva); 10 - Incidents and accidents status and typology (Pascale Scanff, IRSN); 11 - Regional overview of radiation protection significant events (Philippe Menechal, ASN); 12 - Incident leading to a tritium contamination in and urban area - consequences and experience feedback (Laurence Fusil, CEA); 13 - Experience feedback - loss of sealing of a calibration source (Philippe Mougnard, Areva); 14 - Blocking incident of a 60Co source (Bruno Delille, Salvarem); 15 - Triggering of gantry's alarm: status of findings (Philippe Prat, Syctom); 16 - Non-medical electric devices: regulatory changes (Sophie Dagois, IRSN; Jerome Fradin, ASN); 17 - Evaluation of the dose equivalent rate in pulsed fields: method proposed by the IRSN and implementation test (Laurent Donadille, IRSN); 18

  4. A laser beam welding facility for sealing of miniature radiation sources

    International Nuclear Information System (INIS)

    Full text: A Nd : YAG laser welding facility was installed in a radioactive laboratory of the Radiopharmaceuticals Division, BARC to obtain high quality welds of the titanium encased radiation sources. Radiation sources based on 125I for the treatment of ocular tumors were developed and titanium capsules as specified by IS0 standards were fabricated. The inner core of the tiny sources were prepared and were sealed in titanium capsules of dimensions O.8mm (φ) x 4.5mm (1) by laser welding. The laser beam parameters such as energy, frequency, pulse duration and welding speed were optimized to obtain leak proof welds. Laser welds were also characterized by optical and scanning electron microscopy for assessing its quality. The welded sources showed a total release 125I, which is well below the permissible levels. In this paper we describe the laser welding set up and results of initial development work. We also share our experience to obtain radioactive leak proof laser welding of the 125I sources in titanium capsules

  5. Non ionizing radiations: Sources, fields of application, problem issues and normatives

    International Nuclear Information System (INIS)

    The purpose of this paper is briefly to review radiation sources, in work and life places, and national standards, proposed or enforced in different countries, with particular reference to ELF. RF and MW electromagnetic fields. It is aimed to give a help to qualitative valutation on the work we can carry out for the development of an effective health protection of workers and general public. (author)

  6. Safety of radiation sources and the security of radioactive materials in Saudi Arabia

    International Nuclear Information System (INIS)

    The present status of the safety of radiation sources and the security of radioactive materials in Saudi Arabia is reviewed in details. Hazards and potential threat, material control and responsible parties, in addition to management and the technical requirements, are the main topics that are discussed. Some interest is given to the responsibilities of the regulatory authority, with special emphasis on the role of King Abdulaziz city for Science and Technology as a national competent authority. (author)

  7. Non ionizing radiations Sources, fields of application, problem issues and normatives

    CERN Document Server

    Raganella, L

    1988-01-01

    The purpose of this paper is briefly to review radiation sources, in work and life places, and national standards, proposed or enforced in different countries, with particular reference to ELF. RF and MW electromagnetic fields. It is aimed to give a help to qualitative valutation on the work we can carry out for the development of an effective health protection of workers and general public.

  8. Phylogenomics Reveals Three Sources of Adaptive Variation during a Rapid Radiation.

    Directory of Open Access Journals (Sweden)

    James B Pease

    2016-02-01

    Full Text Available Speciation events often occur in rapid bursts of diversification, but the ecological and genetic factors that promote these radiations are still much debated. Using whole transcriptomes from all 13 species in the ecologically and reproductively diverse wild tomato clade (Solanum sect. Lycopersicon, we infer the species phylogeny and patterns of genetic diversity in this group. Despite widespread phylogenetic discordance due to the sorting of ancestral variation, we date the origin of this radiation to approximately 2.5 million years ago and find evidence for at least three sources of adaptive genetic variation that fuel diversification. First, we detect introgression both historically between early-branching lineages and recently between individual populations, at specific loci whose functions indicate likely adaptive benefits. Second, we find evidence of lineage-specific de novo evolution for many genes, including loci involved in the production of red fruit color. Finally, using a "PhyloGWAS" approach, we detect environment-specific sorting of ancestral variation among populations that come from different species but share common environmental conditions. Estimated across the whole clade, small but substantial and approximately equal fractions of the euchromatic portion of the genome are inferred to contribute to each of these three sources of adaptive genetic variation. These results indicate that multiple genetic sources can promote rapid diversification and speciation in response to new ecological opportunity, in agreement with our emerging phylogenomic understanding of the complexity of both ancient and recent species radiations.

  9. Phylogenomics Reveals Three Sources of Adaptive Variation during a Rapid Radiation.

    Science.gov (United States)

    Pease, James B; Haak, David C; Hahn, Matthew W; Moyle, Leonie C

    2016-02-01

    Speciation events often occur in rapid bursts of diversification, but the ecological and genetic factors that promote these radiations are still much debated. Using whole transcriptomes from all 13 species in the ecologically and reproductively diverse wild tomato clade (Solanum sect. Lycopersicon), we infer the species phylogeny and patterns of genetic diversity in this group. Despite widespread phylogenetic discordance due to the sorting of ancestral variation, we date the origin of this radiation to approximately 2.5 million years ago and find evidence for at least three sources of adaptive genetic variation that fuel diversification. First, we detect introgression both historically between early-branching lineages and recently between individual populations, at specific loci whose functions indicate likely adaptive benefits. Second, we find evidence of lineage-specific de novo evolution for many genes, including loci involved in the production of red fruit color. Finally, using a "PhyloGWAS" approach, we detect environment-specific sorting of ancestral variation among populations that come from different species but share common environmental conditions. Estimated across the whole clade, small but substantial and approximately equal fractions of the euchromatic portion of the genome are inferred to contribute to each of these three sources of adaptive genetic variation. These results indicate that multiple genetic sources can promote rapid diversification and speciation in response to new ecological opportunity, in agreement with our emerging phylogenomic understanding of the complexity of both ancient and recent species radiations. PMID:26871574

  10. Superradiant THz undulator radiation source based on a superconducting photo-injector

    Science.gov (United States)

    Wen, Xiaodong; Huang, Senlin; Lin, Lin; Wang, Fang; Zhu, Feng; Feng, Liwen; Yang, Limin; Wang, Zhiwen; Fan, Peiliang; Hao, Jiankui; Quan, Shengwen; Liu, Kexin; Chen, Jia-er

    2016-06-01

    Superconducting radio frequency accelerators are used to produce terahertz (THz) radiation pulses with a high repetition rate. In this study, a compact high repetition rate THz radiation source has been developed based on a DC-SRF photo-injector through velocity bunching at Peking University. This compact THz source can theoretically generate approximately 1 W of superradiant THz radiation, with a repetition rate of 16.25 MHz and a frequency that can be tuned from 0.24 THz to 0.42 THz by varying the electron beam energy from 2.4 MeV to 3.1 MeV. Simulation results indicate that the asymmetrical longitudinal distribution of electrons in each bunch caused by velocity bunching increases the THz power by about 2 orders at wavelength within 400-700 μm. Experimental measurements are consistent with the calculation results when propagation loss is considered. This paper presents the system description, simulation, and experiments of the high repetition rate THz source.

  11. Inspection of radiation sources and regulatory enforcement (supplement to IAEA Safety Standards Series No. GS-G-1.5)

    International Nuclear Information System (INIS)

    The achievement and maintenance of a high level of safety in the use of radiation sources depends on there being a sound legal and governmental infrastructure, including a national regulatory body with well-defined responsibilities and functions. These responsibilities and functions include establishing and implementing a system for carrying out regulatory inspections, and taking necessary enforcement actions. The Safety Requirements publication entitled Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety establishes the requirements for legal and governmental infrastructure. The term 'infrastructure' refers to the underlying structure of systems and organizations. This includes requirements concerning the establishment of a regulatory body for radiation sources and the responsibilities and functions assigned to it. The International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (the Basic Safety Standards or the BSS) establish basic requirements for protection against risks associated with exposure to ionizing radiation and for the safety of radiation sources. The application of the BSS is based on the presumption that national infrastructures are in place to enable governments to discharge their responsibilities to for radiation protection and safety. This TECDOC provides practical guidance on the processes for carrying out regulatory inspections and taking enforcement actions. It includes information on the development and use of procedures and standard review plans (i.e. checklists) for inspection. Specific procedures for inspection of radiation practices and sources are provided in the Appendices

  12. Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory

    International Nuclear Information System (INIS)

    The yearly environmental dose equivalent likely to result at the closest site boundary from the Advanced Light Source was determined by generating multiple linear regressions. The independent variables comprised quantified accelerator operating parameters and measurements from synchronized, in-close (outside shielding prior to significant atmospheric scattering), state-of-the-art neutron remmeters and photon G-M tubes. Neutron regression models were more successful than photon models due to lower relative background radiation and redundant detectors at the site boundary. As expected, Storage Ring Beam Fill and Beam Crashes produced radiation at a higher rate than gradual Beam Decay; however, only the latter did not include zero in its 95% confidence interval. By summing for all three accelerator operating modes, a combined yearly DE of 4.3 mRem/yr with a 90% CI of (0.04-8.63) was obtained. These results fall below the DOE reporting level of 10 mRem/yr and suggest repeating the study with improved experimental conditions

  13. Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Ajemian, R.C. [Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Environmental Sciences and Engineering

    1995-12-31

    The yearly environmental dose equivalent likely to result at the closest site boundary from the Advanced Light Source was determined by generating multiple linear regressions. The independent variables comprised quantified accelerator operating parameters and measurements from synchronized, in-close (outside shielding prior to significant atmospheric scattering), state-of-the-art neutron remmeters and photon G-M tubes. Neutron regression models were more successful than photon models due to lower relative background radiation and redundant detectors at the site boundary. As expected, Storage Ring Beam Fill and Beam Crashes produced radiation at a higher rate than gradual Beam Decay; however, only the latter did not include zero in its 95% confidence interval. By summing for all three accelerator operating modes, a combined yearly DE of 4.3 mRem/yr with a 90% CI of (0.04-8.63) was obtained. These results fall below the DOE reporting level of 10 mRem/yr and suggest repeating the study with improved experimental conditions.

  14. Accelerator-based techniques for the support of senior-level undergraduate physics laboratories

    Science.gov (United States)

    Williams, J. R.; Clark, J. C.; Isaacs-Smith, T.

    2001-07-01

    Approximately three years ago, Auburn University replaced its aging Dynamitron accelerator with a new 2MV tandem machine (Pelletron) manufactured by the National Electrostatics Corporation (NEC). This new machine is maintained and operated for the University by Physics Department personnel, and the accelerator supports a wide variety of materials modification/analysis studies. Computer software is available that allows the NEC Pelletron to be operated from a remote location, and an Internet link has been established between the Accelerator Laboratory and the Upper-Level Undergraduate Teaching Laboratory in the Physics Department. Additional software supplied by Canberra Industries has also been used to create a second Internet link that allows live-time data acquisition in the Teaching Laboratory. Our senior-level undergraduates and first-year graduate students perform a number of experiments related to radiation detection and measurement as well as several standard accelerator-based experiments that have been added recently. These laboratory exercises will be described, and the procedures used to establish the Internet links between our Teaching Laboratory and the Accelerator Laboratory will be discussed.

  15. A new facility for the synchrotron radiation-based calibration of transfer radiation sources in the ultraviolet and vacuum ultraviolet spectral range

    Energy Technology Data Exchange (ETDEWEB)

    Thornagel, Reiner; Fliegauf, Rolf; Klein, Roman, E-mail: roman.klein@ptb.de; Kroth, Simone; Paustian, Wolfgang; Richter, Mathias [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany)

    2015-01-15

    The Physikalisch-Technische Bundesanstalt (PTB) has a long tradition in the calibration of radiation sources in the ultraviolet and vacuum ultraviolet spectral range, with traceability to calculable synchrotron radiation. Within this context, new instrumentation in the PTB laboratory at the Metrology Light Source (MLS) has been put into operation that opens up extended and improved calibration possibilities. A new facility for radiation source calibrations has been set up in the spectral range from 7 nm to 400 nm based on a combined normal incidence-grazing incidence monochromator. The facility can be used for the calibration of transfer sources in terms of spectral radiant intensity or mean spectral radiance, with traceability to the MLS primary source standard. We describe the design and performance of the experimental station and give examples of some commissioning results.

  16. Nuclear law: nuclear matter and ionizing radiation sources. Wastes; Droit nucleaire: matieres nucleaires et sources de rayonnements ionisants. Dechets

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-15

    The object of this work is since its first edition in 1983 under the title 'Collection of nuclear activities legislation and regulation ' to realize an ordered collection of texts constituting the juridical and institutional frame of nuclear activities, gathering the legislative, regulatory and technical texts; the international, European and national texts. Aiming to include the whole of the atom applications, this collection tackles various themes, in ten chapters.The volume number two includes the following chapters: nuclear matters and ionizing radiations sources; wastes. Previously edited by the Cea, that realizes it it is now published in the collection 'Legislation and regulation' of officials journals editions. (N.C.)

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

    Science.gov (United States)

    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.

  18. Safety of radiation sources and security of radioactive materials. Proceedings of an international conference

    International Nuclear Information System (INIS)

    This International Conference, hosted by the Government of France and co-sponsored by the European Commission, the International Criminal Police Organization (Interpol) and the World Customs Organization (WCO), was the first one devoted to the safety of radiation sources and the security of radioactive materials and - for the first time - brought together radiation safety experts, regulators, and customs and police officers, who need to closely co-operate for solving the problem of illicit trafficking. The technical sessions reviewed the state of the art of twelve major topics, divided into two groups: the safety of radiation sources and the security of radioactive materials. The safety part comprised regulatory control, safety assessment techniques, engineering and managerial measures, lessons from experience, international cooperation through reporting systems and databases, verification of safety through inspection and the use of performance indicators for a regulatory programme. The security part comprised measures to prevent breaches in the security of radioactive materials, detection and identification techniques for illicit trafficking, response to detected cases and seized radioactive materials, strengthening awareness, training and exchange of information. The Conference was a success in fostering information exchange through the reviews of the state of the art and the frank and open discussions. It raised awareness of the need for Member States to ensure effective systems of control and for preventing, detecting and responding to illicit trafficking in radioactive materials. The Conference finished by recommending investigating whether international undertakings concerned with an effective operation of national systems for ensuring the safety of radiation sources and security of radioactive materials

  19. Radiation of planar electromagnetic waves by a line source in anisotropic metamaterials

    Science.gov (United States)

    Cheng, Qiang; Jiang, Wei Xiang; Cui, Tie Jun

    2010-08-01

    We show experimentally that a line source in an anisotropic metamaterial directly radiates planar electromagnetic waves instead of cylindrical waves, when one component of the permeability tensor approaches zero. The impedance of this material can be perfectly matched to that of free space, which can significantly reduce the reflections between the source and the superstrate, as in traditional highly directive antennas based on zero index metamaterials. Such a unique property determines the two-way propagation of electromagnetic waves excited by a line source, instead of all-way propagation. From this feature, a highly directive emission of electromagnetic waves is achieved using the anisotropic metamaterial with arbitrary shape. We have designed and fabricated the anisotropic metamaterial in the microwave region, and observed the generation of plane waves and their highly directive emission. The proposed plane-wave emission is independent of the shape variance of the anisotropic metamaterial, which can be utilized in the design of conformal antennas.

  20. The Role and Responsibility of the National Regulator of Radiation Sources and Materials in Saudi Arabia

    International Nuclear Information System (INIS)

    There are neither nuclear power reactors nor are there research reactors in Saudi Arabia. However, the country imports a lot of radioactive sources that are used in different fields such as medicine, hydrology, industry and research. Usage of radioactive material is governed by national and the IAEA regulations for the safe usage and transport of radioactive materials. KACST (King Abdulaziz City for Science and Technology) is an independent scientific organization established in 1977. It is the national competent authority that sets the rules of transporting, using and disposing of radioactive sources in Saudi Arabia.. This paper discusses the role of KACST and other authorities in the country regarding the 1) licensing and evaluation of the importing and exporting applications of radioactive sources and/or devices in Saudi Arabia, 2) The regulatory framework of radiation protection in Saudi Arabia, 3) the management of radioactive wastes in Saudi Arabia. (author)

  1. Radiation of planar electromagnetic waves by a line source in anisotropic metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Qiang; Jiang Weixiang; Cui Tiejun, E-mail: tjcui@seu.edu.c [State Key Laboratory of Millimeter Waves, Department of Radio Engineering, Southeast University, Nanjing 210096 (China)

    2010-08-25

    We show experimentally that a line source in an anisotropic metamaterial directly radiates planar electromagnetic waves instead of cylindrical waves, when one component of the permeability tensor approaches zero. The impedance of this material can be perfectly matched to that of free space, which can significantly reduce the reflections between the source and the superstrate, as in traditional highly directive antennas based on zero index metamaterials. Such a unique property determines the two-way propagation of electromagnetic waves excited by a line source, instead of all-way propagation. From this feature, a highly directive emission of electromagnetic waves is achieved using the anisotropic metamaterial with arbitrary shape. We have designed and fabricated the anisotropic metamaterial in the microwave region, and observed the generation of plane waves and their highly directive emission. The proposed plane-wave emission is independent of the shape variance of the anisotropic metamaterial, which can be utilized in the design of conformal antennas.

  2. Safety of radiation sources and security of radioactive materials. Contributed papers

    International Nuclear Information System (INIS)

    The International Atomic Energy Agency (IAEA) in co-operation with the European Commission (EC), International Criminal Police Organization (INTERPOL) and the World Customs Organization (WCO) organized an International Conference on the Safety of Radiation Sources and the Security of Radioactive Materials, in Dijon, France, from 14 to 18 September 1998. The Government of France hosted this Conference through the Commissariat a l'energie atomique, Direction des applications militaires (CEA/DAM). This TECDOC contains the contributed papers dealing with the topics of this Conference which were accepted by the Conference Programme Committee for presentation. The papers written in one of the two working languages of the Conference, English or French are presented here each by a separate abstract. Ten technical sessions covered the following subjects: the regulatory control of radiation sources, including systems for notification, authorization and inspection; safety assessment techniques applied to radiation sources and design and technological measures including defense in depth and good engineering practice; managerial measures, including safety culture, human factors, quality assurance, qualified experts, training and education; learning from operational experience; international co-operation, including reporting systems and databases; verification of compliance, monitoring of compliance and assessment of the effectiveness of national programmes for the safety of sources; measures to prevent breaches in the security of radioactive materials, experience with criminal acts involving radioactive materials; detection and identification technologies for illicitly trafficked radioactive materials; response to detected cases and seized radioactive materials, strengthening of the awareness, training and exchange of information. The IAEA plans to issue the proceedings of this Conference containing the invited presentations, rapporteurs and Chairpersons overviews and summaries

  3. Radiation dose estimates in dual-source computed tomography coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Stolzmann, Paul; Scheffel, Hans; Schertler, Thomas; Frauenfelder, Thomas; Leschka, Sebastian; Husmann, Lars; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Flohr, Thomas G. [Siemens Medical Solutions, Forchheim (Germany); Kaufmann, Philipp A. [Cardiovascular Center, Forchheim (Germany)

    2008-03-15

    The purpose of this study was to quantify radiation dose parameters of dual-source CT coronary angiography. Eighty patients underwent contrast-enhanced, retrospectively ECG-gated dual-source CT coronary angiography with heart rate-adapted ECG pulsing using two algorithms: In 40 patients, the tube current was reduced to 20% (A{sub min1}) of the normal tube current (A{sub max}) outside the pulsing window; in 40 patients tube current was reduced to 4% (A{sub min2}) of A{sub max}. Mean CTDI{sub vol} in the A{sub min1} group was 45.1 {+-} 3.6 mGy; the mean CTDI{sub vol} in the A{sub min2} group was 39.1 {+-} 3.2 mGy, with CTDI{sub vol} in the A{sub min2} group being significantly reduced when compared to the A{sub min1} group (P < 0.001). A significant negative correlation was found between CTDI{sub vol} and heart rate in group A{sub min1} (r = -0.82, P < 0.001), whereas no correlation was found between CTDI{sub vol} and heart rate in group A{sub min2} (r = -0.066). Using the conversion coefficient for the chest, dual-source CT coronary angiography resulted in an estimated mean effective dose of 8.8 mSv in the A{sub min1} group and 7.8 mSv in the A{sub min2}. Radiation exposure of dual-source CT coronary angiography using an ECG-pulsing protocol reducing the tube current to 20% significantly decreases with increasing heart rates, despite using wider pulsing windows at higher heart rates. When using a protocol with reduced tube current of 4%, the radiation dose is significantly lower, irrespective of the heart rate. (orig.)

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

    Science.gov (United States)

    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.

  5. Physical conditions for sources radiating a cosh-Gaussian model beam

    Institute of Scientific and Technical Information of China (English)

    LI Jia

    2011-01-01

    Based on the coherence theory of diffracted optical field and the model for partially coherent beams, analytical expressions for the cross-spectral density and the irradiance spectral density in the far zone are derived, respectively. Utilizing the theoretical model of radiation from secondary planar sources, the physical conditions for sources generating a cosh-Gaussian (CHG) beam are investigated. Analytical results demonstrate that the parametric conditions strongly depend on the coherence property of sources. When almost coherence property is satisfied in the source plane, the conditions are the same as those for fundamental Gaussian beams; when partial coherence or almost incoherence property is satisfied in the spatial source plane, the conditions are the same as those for Gaussian-Schell model beams. The results also indicate that the variance of cosine parameters has no influence on the conditions. Our results may provide potential applications for some investigations such as the modulations of cosh-Gaussian beams and the designs of source beam parameters.

  6. Estimated population exposure from nuclear power production and other radiation sources

    International Nuclear Information System (INIS)

    Estimates are given of the total radiation dose from all forms of ionizing radiation resulting from nuclear power reduction. A power consumption of 1kW per head of population, derived entirely from nuclear energy, would increase the average radiation exposure of the whole population from 100mrem per year from natural sources (plus about 40mrem per year from medical procedures and other artificial causes) by about 6mrem per year. The genetically signifificant component of this increase would be about 4mrem per year. Available estimates of harm from radiation would indicate that this would give a risk per year per million of population of about 1 fatal induced malignancy, about the same number of malignancies fully treatable by operation, and, after many generations, about the same number of inherited defects, of greater or less severity, per year. Accidental injuries, particularly in constructional and mining work, would cause an estimated 1 fatality and 50 other accidents annually. Indications are given of the number of fatalities and accidents involved in equal power production by alternative methods, and of the value and limitations of such numerical comparisons in reaching decisions on the development of future power programmes

  7. Spectrum shaping of accelerator-based neutron beams for BNCT

    CERN Document Server

    Montagnini, B; Esposito, J; Giusti, V; Mattioda, F; Varone, R

    2002-01-01

    We describe Monte Carlo simulations of three facilities for the production of epithermal neutrons for Boron Neutron Capture Therapy (BNCT) and examine general aspects and problems of designing the spectrum-shaping assemblies to be used with these neutron sources. The first facility is based on an accelerator-driven low-power subcritical reactor, operating as a neutron amplifier. The other two facilities have no amplifier and rely entirely on their primary sources, a D-T fusion reaction device and a conventional 2.5 MeV proton accelerator with a Li target, respectively.

  8. Management of radiation sources and personal dosimeters based on the optical identification using two-dimensional barcode

    International Nuclear Information System (INIS)

    For accurate and efficient radiation safety management in facilities using radioisotopes, two-dimensional barcode (2-DC) was applied to the optical identification of radiation sources and personal dosimeters. The mobile personal computer (PC) equipped with a barcode reader, which has imported inventory records from the pre-existing radiation management system, enabled us to finish inventory procedures for 170 2-DC-labelled radiation sources in as short as 20min by one person. Identification of 270 personal dosimeters in their monthly replacement procedures also successfully completed within 20 min by incorporating pre-labeled 2-DC to PC installed with inventory records of dosimeters and radiation workers. As equipments and software required for 2-DC are affordable, easy to operate, and potentially expandable, the introduction of 2-DC system may help to establish practically higher level of radiation management. (author)

  9. Virtual monochromatic imaging in dual-source dual-energy CT: Radiation dose and image quality

    International Nuclear Information System (INIS)

    Purpose: To evaluate the image quality of virtual monochromatic images synthesized from dual-source dual-energy computed tomography (CT) in comparison with conventional polychromatic single-energy CT for the same radiation dose. Methods: In dual-energy CT, besides the material-specific information, one may also synthesize monochromatic images at different energies, which can be used for routine diagnosis similar to conventional polychromatic single-energy images. In this work, the authors assessed whether virtual monochromatic images generated from dual-source CT scanners had an image quality similar to that of polychromatic single-energy images for the same radiation dose. First, the authors provided a theoretical analysis of the optimal monochromatic energy for either the minimum noise level or the highest iodine contrast to noise ratio (CNR) for a given patient size and dose partitioning between the low- and high-energy scans. Second, the authors performed an experimental study on a dual-source CT scanner to evaluate the noise and iodine CNR in monochromatic images. A thoracic phantom with three sizes of attenuating rings was used to represent four adult sizes. For each phantom size, three dose partitionings between the low-energy (80 kV) and the high-energy (140 kV) scans were used in the dual-energy scan. Monochromatic images at eight energies (40 to 110 keV) were generated for each scan. Phantoms were also scanned at each of the four polychromatic single energy (80, 100, 120, and 140 kV) with the same radiation dose. Results: The optimal virtual monochromatic energy depends on several factors: phantom size, partitioning of the radiation dose between low- and high-energy scans, and the image quality metrics to be optimized. With the increase of phantom size, the optimal monochromatic energy increased. With the increased percentage of radiation dose on the low energy scan, the optimal monochromatic energy decreased. When maximizing the iodine CNR in

  10. Thulium-170 oxide heat source experimental and analytical radiation and shielding study

    International Nuclear Information System (INIS)

    Radiation dose rates from three thulium-170 oxide sources (20.7, 10.0 and 5.0 thermal watts) were measured through three thicknesses (1/4, 1/2 and 1 inch) of absorber by thermoluminescent dosimetry techniques. Absorber materials used were aluminium, stainless steel, lead, tungsten and depleted uranium. Resultant radiation doses were measured at 19 and 100 cm. Comparison of theoretical dose rates calculated by computer with measured dose rates validated the calculation technique for lead, tungsten and uranium absorbers but not for aluminum and stainless steel. Use of infinite medium build-up factors (B/sub ∞/) was thus validated in computation of dose rates for lead, tungsten and uranium absorbers; use of B/sub ∞/ in computation of dose rates for aluminum and stainless steel absorbers overestimated dose rates vis-a-vis experimentally determined dose rates by an approximate factor of 2

  11. Inverse determination of heat source distribution in conductive-radiative media with irregular geometry

    Energy Technology Data Exchange (ETDEWEB)

    Sarvari, S.M.H. [Mechanical Engineering Department, Sistan and Baluchestan University, 98135-161, Zahedan (Iran, Islamic Republic of)]. E-mail: sarvari@hamoon.usb.ac.ir

    2005-06-15

    This work investigates the inverse problem of finding the two-dimensional heat source distribution in an irregular conductive-radiative medium to satisfy the desired temperature and heat flux distributions over the design surface. The participating medium is gray and non-scattering, the walls are diffuse and gray, and all the thermal properties are uniform. The conjugate gradient method is used to minimize an objective function, expressed by the sum of square residuals between estimated and desired heat fluxes over the design surface. A combination of the finite element method with the discrete transfer method is used to solve the direct problem of conductive-radiative heat transfer. The results of the problem are in good agreement with available numerical solution. The performance and ability of the method for irregular geometries is investigated by an example problem.

  12. Software development for studies of diffuse scattering using CCD-detectors and synchrotron radiation sources

    CERN Document Server

    Paulmann, C; Bismayer, U

    2001-01-01

    A graphical-user-interface based software system was developed to cover advanced data processing requirements which arise from studies of diffuse scattering in disordered minerals using synchrotron radiation sources and CCD-detectors. The software includes interfaces to standard applications, procedures for numerical processing of large data sets, corrections for sample external scattering and detector-specific distortions, different scaling options to correct the data set against the varying primary beam intensity as well as procedures to reconstruct arbitrary slices in reciprocal space on a regular grid. The software system was successfully applied in studies of diffuse scattering in disordered REE-doped germanates, phase-transition studies of synthetic titanite and studies of the thermal recrystallization behaviour of radiation-damaged (metamict) minerals.

  13. Parallax diagnostics of radiation source geometric dilution for iron opacity experiments

    CERN Document Server

    Nagayama, T; Loisel, G; Rochau, G A; Falcon, R E

    2014-01-01

    Experimental tests are in progress to evaluate the accuracy of the modeled iron opacity at solar interior conditions [J.E. Bailey et al., Phys. Plasmas 16, 058101 (2009)]. The iron sample is placed on top of the Sandia National Laboratories z-pinch dynamic hohlraum (ZPDH) radiation source. The samples are heated to 150 - 200 eV electron temperatures and 7e21 - 4e22 e/cc electron densities by the ZPDH radiation and backlit at its stagnation [T. Nagayama et al., Phys. Plasmas 21, 056502 (2014)]. The backlighter attenuated by the heated sample plasma is measured by four spectrometers along +/- 9 degree with respect to the z-pinch axis to infer the sample iron opacity. Here we describe measurements of the source-to-sample distance that exploit the parallax of spectrometers that view the half-moon-shaped sample from +/-9 degree. The measured sample temperature decreases with increased source-to-sample distance. This distance must be taken into account for understanding the sample heating.

  14. [Radiation safety during work on the ANET-V therapeutic apparatus with 252Cf sources].

    Science.gov (United States)

    Chekhonadskiĭ, V N; Drygin, V N; Vaĭnberg, M Sh; Komar, V Ia; Elisiutin, G P

    1985-03-01

    The Soviet ANET-W intracavitary neutron therapy apparatus is charged with 252Cf sources, the total mass of the radionuclide being 2100 micrograms. The radiation exposure of the staff has been studied and the results presented. Possible emergency situations have been analysed, methods of their prevention and liquidation worked out. Induced radioactivity in the patient's body has been estimated. Radiation dose levels for the medical staff are 10-15 times lower for the ANET-W apparatus than those for 252Cf sources administered by the manual series system but 10 times higher than those for the AGAT-W gamma-apparatus. The design, blocking system and emergency reset of the sources provide for safe work on the ANET-W apparatus. During liquidation of an emergency situation irradiation of the staff does not exceed 0.3 of the annual maximum tolerance dose. The level of induced activity in the patient's body is insignificant as in 10.5 min it does not exceed background values. PMID:3982256

  15. Synchrotron radiation study of the uranium chemical species electrodeposited for alpha spectrometry sources

    Energy Technology Data Exchange (ETDEWEB)

    Burciaga V, D. C.; Mendez, C. G.; Esparza P, H.; Fuentes C, L.; Fuentes M, L.; Montero C, M. E. [Centro de Investigacion en Materiales Avanzados, S. C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31109 Chihuahua (Mexico); Beesley, A. M. [School of Chemical Engineering and Analytical Science, University of Manchester, Oxford Road, M13 9PL Manchester (United Kingdom); Crespo, M. T., E-mail: elena.montero@cimav.edu.m [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Laboratorio de Metrologia de Radiaciones Ionizantes, Avda. Complutense 22, 28040 Madrid (Spain)

    2011-02-15

    Alpha spectrometry (As) with semiconductor detectors has applications in nuclear decay data measurements, environmental, geological and nuclear wastes studies and other works requiring determination of actinide and other alpha emitter contents. In order to obtain accurate measurements by producing good resolution alpha spectra, As sources must be thin and uniform. As sources produced by electrodeposition consist of a radioactive deposit onto a metallic substrate (cathode of the electrolytic cell). Natural U sources prepared by the Hallstadius method have co-deposited Pt, originated from the dissolution of the anode during the electrodeposition. A recent work published else-where has reported a study on the morphology and spatial distribution of the U/Pt deposits with the related chemical speciation of U, using scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and X-ray absorption fine structure. The purpose of this work is to explain the structure of the Pt/U deposits. We have obtained new spectra of the U L III edge X-ray absorption fine structure by total electron yield at Stanford Synchrotron radiation light source, Bl 2-3. Grazing incidence X-ray diffraction (Gi-XRD) patterns were obtained at Stanford Synchrotron radiation light source, Bl 11-3. Gi-XRD patterns show a bimodal distribution of grain sizes of Pt, with dimensions {approx} 5 and 20 nm; schoepite diffraction signals suggest grain dimensions of {approx} 5 nm, i.e. with low crystallization. X-ray absorption fine structure spectra were fitted assuming two different structures: uranyl hydroxide and schoepite, and results were compared. U-U path shows low intensity that also may be a result of low crystallization. (Author)

  16. Radiation Protection Aspects of Primary Water Chemistry and Source-term Management Report

    International Nuclear Information System (INIS)

    Since the beginning of the 1990's, occupational exposures in nuclear power plant has strongly decreased, outlining efforts achieved by worldwide nuclear operators in order to reach and maintain occupational exposure as low as reasonably achievable (ALARA) in accordance with international recommendations and national regulations. These efforts have focused on both technical and organisational aspects. According to many radiation protection experts, one of the key features to reach this goal is the management of the primary system water chemistry and the ability to avoid dissemination of radioactivity within the system. It outlines the importance for radiation protection staff to work closely with chemistry staff (as well as operation staff) and thus to have sufficient knowledge to understand the links between chemistry and the generation of radiation field. This report was prepared with the primary objective to provide such knowledge to 'non-chemist'. The publication primarily focuses on three topics dealing with water chemistry, source term management and remediation techniques. One key objective of the report is to provide current knowledge regarding these topics and to address clearly related radiation protection issues. In that mind, the report prepared by the EGWC was also reviewed by radiation protection experts. In order to address various designs, PWRs, VVERs, PHWRs and BWRs are addressed within the document. Additionally, available information addressing current operating units and lessons learnt is outlined with choices that have been made for the design of new plants. Chapter 3 of this report addresses current practices regarding primary chemistry management for different designs, 'how to limit activity in the primary circuit and to minimise contamination'. General information is provided regarding activation, corrosion and transport of activated materials in the primary circuit (background on radiation field generation). Primary chemistry aspects that

  17. Organization and implementation of a national regulatory infrastructure governing protection against ionizing radiation and the safety of radiation sources. Interim report for comment

    International Nuclear Information System (INIS)

    A number of IAEA Member States are undertaking to strengthen their radiation protection and safety infrastructures in order to facilitate the adoption of the requirements established in the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (the Standards). In this connection, the IAEA has developed a technical co-operation programme (Model Project on Upgrading Radiation Protection Infrastructure) to improve radiation protection and safety infrastructures in 51 Member States, taking into account national profiles and needs of the individual participating, countries. The present report deals with the elements of a regulatory infrastructure for radiation protection and safety and intends to facilitate the, implementation of the Basic Safety Standards in practice. It takes into account the proposals in an earlier report, IAEA-TECDOC-663, but it has been expanded to include enabling legislation and modified to be more attuned to infrastructure issues related to implementation of the Standards. The orientation is toward infrastructures concerned with protection and safety for radiation sources used in medicine, agriculture, research, industry and education rather than infrastructures for protection and safety for complex nuclear facilities. It also discusses options for enhancing the effectiveness and efficiency of the infrastructure in accordance with the size and scope of radiation practices and available regulatory resources within a country

  18. Development of an accelerator-based BNCT facility at the Berkeley Lab

    International Nuclear Information System (INIS)

    An accelerator-based BNCT facility is under construction at the Berkeley Lab. An electrostatic-quadrupole (ESQ) accelerator is under development for the production of neutrons via the 7Li(p,n)7Be reaction at proton energies between 2.3 and 2.5 MeV. A novel type of power supply, an air-core coupled transformer power supply, is being built for the acceleration of beam currents exceeding 50 mA. A metallic lithium target has been developed for handling such high beam currents. Moderator, reflector and neutron beam delimiter have extensively been modeled and designs have been identified which produce epithermal neutron spectra sharply peaked between 10 and 20 keV. These. neutron beams are predicted to deliver significantly higher doses to deep seated brain tumors, up to 50% more near the midline of the brain than is possible with currently available reactor beams. The accelerator neutron source will be suitable for future installation at hospitals

  19. Linear accelerator based stereotactic radiosurgery for melanoma brain metastases

    Directory of Open Access Journals (Sweden)

    Mark E Bernard

    2012-01-01

    Full Text Available Purpose: Melanoma is one of the most common malignancies to metastasize to the brain. Many patients with this disease will succumb to central nervous system (CNS disease, highlighting the importance of effective local treatment of brain metastases for both palliation and survival of the disease. Our objective was to evaluate the outcomes associated with stereotactic radiosurgery (SRS in the treatment of melanoma brain metastases. Materials and Methods: We retrospectively reviewed 54 patients with a total of 103 tumors treated with SRS. Twenty patients had prior surgical resection and nine patients underwent prior whole brain radiation therapy (WBRT. 71% of patients had active extracranial disease at the time of SRS. Median number of tumors treated with SRS was 1(range: 1-6 with median radiosurgery tumor volume 2.1 cm 3 (range: 0.05-59.7 cm 3 . The median dose delivered to the 80% isodose line was 24 Gy in a single fraction. Results: The median follow-up from SRS was five months (range:1-30 months. Sixty-five percent of patients had a follow-up MRI available for review. Actuarial local control at six months and 12 months was 87 and 68%, respectively. Eighty-one percent of patients developed new distant brain metastases at a median time of two months. The six-month and 12-month actuarial overall survival rates were 50 and 25%, respectively. The only significant predictor of overall survival was surgical resection prior to SRS. Post-SRS bleeding occurred in 18% of patients and at a median interval of 1.5 months. There was only one episode of radiation necrosis with no other treatment-related toxicity. Conclusion: SRS for brain metastases from melanoma is safe and achieves acceptable local control.

  20. Computation methods for neutron, heat and radiation damage properties of pulsed neutron sources

    International Nuclear Information System (INIS)

    The results of calculations of neutron yield, heat and nuclei-products distributions for heavy extended targets (natural W, Pb, and depleted U cylindrical targets; D=20 cm, L=60 cm) irradiated with proton beam of energy up to 100 GeV are presented as well as the radiation damage cross sections for thin layers of structure materials. The calculations were made with Monte Carlo method on the base of exclusive high energy hadron transport code SHIELD. The comparison with available experimental data is given. An expediency of elaboration of spallation neutron source based on high-energy accelerator is briefly discussed. (author) 5 figs., 17 refs

  1. Photo absorption studies of polyatomic molecules using Indus 1 synchrotron radiation source

    International Nuclear Information System (INIS)

    The Photophysics beamline is a medium resolution beamline designed for carrying out photo absorption and fluorescence experiments using the synchrotron radiation source Indus-l. This beamline has been commissioned recently and is in operation. An experimental setup for gas phase absorption studies has been developed and installed. Absorption spectra of a few polyatomicmolecules viz. benzene, ammonia, carbon disulphide and acetone were recorded in the wavelength region 1500 -3000 A. The results from this study indicated the satisfactory performance of the beam line as well as the experimental setup. Details of the first set of absorption experiments carried out are discussed in this report. (author)

  2. Novel radiation sources using relativistic electrons from infrared to x-rays

    CERN Document Server

    Rullhusen, P; Dhez, P

    1998-01-01

    The purpose of this book is to give a description of the state of the art in theoretical and experimental work achieved in radiation source development. It summarizes clearly and comprehensibly, the basic physical aspects needed to understand the phenomena, and also provides the interested reader with sufficient literature to be able to follow the development in more detail. In addition, it contains a unified view of most theoretical effects and their common properties. The most recent developments as well as references to further work can be found in this volume. In many cases, review article

  3. Audits by registrants authorized for use of radiation sources in well logging

    International Nuclear Information System (INIS)

    An audit was carried out by the Argentine Nuclear Regulatory Authority to verify regulations and safe working procedures compliance by registrants authorized for use of radiation sources in well logging. A task force based on four inspection teams was organized. The audit was carried out at registrant's premises (equipment storage facilities) simultaneously. The evaluation was based on a system allowing a fast qualification of both, potential problems identified and their solutions. The results show that 95 % of the inspected locations were classified under the 'acceptable', 'good' and 'very good' headings. (author)

  4. Modelling the Impact of Ground Planes on Antenna Radiation Using the Method of Auxiliary Sources

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2007-01-01

    The Method of Auxiliary Sources is employed to model the impact of finite ground planes on the radiation from antennas. In many cases the computational cost of available commercial tools restricts the simulations to include only a small ground plane or, by use of the image principle, the infinitely...... simulation results for the case of crossed Hertzian dipoles antennas. Later the method is applied to the cases of real antennas, a slot antenna and a printed dipole phased array, for which corresponding measurements have been conducted. The results obtained with the method agree well with the simulated...

  5. New estimates of asymmetric decomposition of racemic mixtures by natural β-radiation sources

    International Nuclear Information System (INIS)

    The Vester-Ulbricht (V-U) hypothesis suggests that the chirality of biological molecules originates from the beta-radiolysis of prebiotic racemic mixtures. However recent calculations of asymmetric decomposition of racemic mixtures by natural beta-radiation sources have indicated that the hypothesis was invalid. Here the authors re-examine the major assumptions on which these calculations were based, and find that several restrictive conditions were imposed, which when relaxed, does not exclude the V-U hypothesis. (U.K.)

  6. Physiologically gated microbeam radiation using a field emission x-ray source array

    Energy Technology Data Exchange (ETDEWEB)

    Chtcheprov, Pavel, E-mail: PavelC@unc.edu, E-mail: zhou@email.unc.edu [Department of Biomedical Engineering, University of North Carolina, 152 MacNider Hall, Campus Box 7575, Chapel Hill, North Carolina 27599 (United States); Burk, Laurel; Inscoe, Christina; Ger, Rachel; Hadsell, Michael; Lu, Jianping [Department of Physics and Astronomy, University of North Carolina, Phillips Hall, CB #3255, 120 East Cameron Avenue, Chapel Hill, North Carolina 27599 (United States); Yuan, Hong [Department of Radiology, University of North Carolina, 2006 Old Clinic, CB #7510, Chapel Hill, North Carolina 27599 (United States); Zhang, Lei [Department of Applied Physical Sciences, University of North Carolina, Chapman Hall, CB#3216, Chapel Hill, North Carolina 27599 (United States); Chang, Sha [Department of Radiation Oncology, University of North Carolina, 101 Manning Drive, Chapel Hill, North Carolina 27514 and UNC Lineberger Comprehensive Cancer Center, University of North Carolina, 101 Manning Drive, Chapel Hill, North Carolina 27514 (United States); Zhou, Otto, E-mail: PavelC@unc.edu, E-mail: zhou@email.unc.edu [Department of Physics and Astronomy, University of North Carolina, Phillips Hall, CB #3255, 120 East Cameron Avenue, Chapel Hill, North Carolina 27599 and UNC Lineberger Comprehensive Cancer Center, University of North Carolina, 101 Manning Drive, Chapel Hill, North Carolina 27514 (United States)

    2014-08-15

    Purpose: Microbeam radiation therapy (MRT) uses narrow planes of high dose radiation beams to treat cancerous tumors. This experimental therapy method based on synchrotron radiation has been shown to spare normal tissue at up to 1000 Gy of peak entrance dose while still being effective in tumor eradication and extending the lifetime of tumor-bearing small animal models. Motion during treatment can lead to significant movement of microbeam positions resulting in broader beam width and lower peak to valley dose ratio (PVDR), which reduces the effectiveness of MRT. Recently, the authors have demonstrated the feasibility of generating microbeam radiation for small animal treatment using a carbon nanotube (CNT) x-ray source array. The purpose of this study is to incorporate physiological gating to the CNT microbeam irradiator to minimize motion-induced microbeam blurring. Methods: The CNT field emission x-ray source array with a narrow line focal track was operated at 160 kVp. The x-ray radiation was collimated to a single 280 μm wide microbeam at entrance. The microbeam beam pattern was recorded using EBT2 Gafchromic{sup ©} films. For the feasibility study, a strip of EBT2 film was attached to an oscillating mechanical phantom mimicking mouse chest respiratory motion. The servo arm was put against a pressure sensor to monitor the motion. The film was irradiated with three microbeams under gated and nongated conditions and the full width at half maximums and PVDRs were compared. An in vivo study was also performed with adult male athymic mice. The liver was chosen as the target organ for proof of concept due to its large motion during respiration compared to other organs. The mouse was immobilized in a specialized mouse bed and anesthetized using isoflurane. A pressure sensor was attached to a mouse's chest to monitor its respiration. The output signal triggered the electron extraction voltage of the field emission source such that x-ray was generated only

  7. Orbit correction using an eigenvector method with constraints for synchrotron radiation sources

    Science.gov (United States)

    Harada, Kentaro; Obina, Takashi; Kobayashi, Yukinori; Nakamura, Norio; Takaki, Hiroyuki; Sakai, Hiroshi

    2009-06-01

    An eigenvector method with constraints (EVC) is proposed as a new orbit correction scheme for synchrotron light sources. EVC efficiently corrects the global orbit in a storage ring, and can simultaneously perform exact correction of local orbits without deterioration of the global orbit. To demonstrate the advantages of EVC over the ordinary eigenvector method (EV), we carried out experimental studies at the Photon Factory storage ring (PF-ring) and the Photon Factory Advanced Ring (PF-AR) at the High Energy Accelerator Research Organization (KEK). The performance of EVC was systematically examined at PF-ring and PF-AR. The experimental results agreed well with the simulated ones. Consequently, we confirmed that EVC easily realized orbit correction for both global and local orbits, and that it was very effective for the beam stabilization of synchrotron radiation (SR) sources.

  8. Orbit correction using an eigenvector method with constraints for synchrotron radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Kentaro [Photon Factory, High Energy Accelerator Research Organization, 1-1, Oho, Tsukuba, Ibaraki 305-0801 (Japan)], E-mail: kentaro.harada@kek.jp; Obina, Takashi; Kobayashi, Yukinori [Photon Factory, High Energy Accelerator Research Organization, 1-1, Oho, Tsukuba, Ibaraki 305-0801 (Japan); Nakamura, Norio; Takaki, Hiroyuki; Sakai, Hiroshi [Institute for Solid State Physics, University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan)

    2009-06-11

    An eigenvector method with constraints (EVC) is proposed as a new orbit correction scheme for synchrotron light sources. EVC efficiently corrects the global orbit in a storage ring, and can simultaneously perform exact correction of local orbits without deterioration of the global orbit. To demonstrate the advantages of EVC over the ordinary eigenvector method (EV), we carried out experimental studies at the Photon Factory storage ring (PF-ring) and the Photon Factory Advanced Ring (PF-AR) at the High Energy Accelerator Research Organization (KEK). The performance of EVC was systematically examined at PF-ring and PF-AR. The experimental results agreed well with the simulated ones. Consequently, we confirmed that EVC easily realized orbit correction for both global and local orbits, and that it was very effective for the beam stabilization of synchrotron radiation (SR) sources.

  9. Survey of the cosmetic use of lasers and other strong optical radiation sources

    International Nuclear Information System (INIS)

    A survey was undertaken regarding the extent to which optical radiation is used in cosmetic treatments and the compliance with national regulations. Questionnaires were sent to 65 clinics, and 23 of these were later inspected. Only one of 41 class 4 lasers had been reported to the authorities according to the regulations prior to the survey. Among sources other than lasers, intense pulsed light (IPL) sources were the most frequent. Although qualified health personnel should be in charge of the treatment, it was observed that 30% of the clinics did not fulfil this requirement. Deviations with respect to personnel training, availability of written procedures, protective equipment and warning signs were frequently observed. The results give rise to concern about the safety of patients and employees.

  10. Developing and implementing safety culture in the uses of radiation sources

    International Nuclear Information System (INIS)

    This paper presents an approach to develop and implement safety culture in the uses of radiation sources in medicine, industry, agriculture, research and teaching, and makes reference to the experience gained by the industries where that culture has been developed and improved, i.e. the nuclear industry. Suggestions to assist progress toward safety culture are here described for regulators, organisations using those sources, and professional associations. Even though emphasis is given to small organisations or teams of workers, this approach may be also useful to greater organisations like industrial irradiation companies or governmental research laboratories. In each case, parties being the principal focus of the learning process toward a progressive safety culture should be identified. (author)

  11. The enhanced volume source boundary point method for the calculation of acoustic radiation problem

    Institute of Scientific and Technical Information of China (English)

    WANG Xiufeng; CHEN Xinzhao; WANG Youcheng

    2003-01-01

    The Volume Source Boundary Point Method (VSBPM) is greatly improved so that it will speed up the VSBPM's solution of the acoustic radiation problem caused by the vibrating body. The fundamental solution provided by Helmholtz equation is enforced in a weighted residual sense over a tetrahedron located on the normal line of the boundary node to replace the coefficient matrices of the system equation. Through the enhanced volume source boundary point analysis of various examples and the sound field of a vibrating rectangular box in a semi-anechoic chamber, it has revealed that the calculating speed of the EVSBPM is more than 10 times faster than that of the VSBPM while it works on the aspects of its calculating precision and stability, adaptation to geometric shape of vibrating body as well as its ability to overcome the non-uniqueness problem.

  12. An effect of stimulated radiation processes on radio emission from extended sources

    CERN Document Server

    Prigara, F V

    2003-01-01

    Both the standard theory of thermal radio emission and the synchrotron theory encounter some difficulties. The most crucial for the former one is nonpossibility to explain the radio spectrum of Venus in the decimeter range (Ksanfomality 1985). The radio spectra of planetary nebulae at high frequencies also are not comfortably consistent with the standard theory (Siodmiak & Tylenda 2001). Here we show that the account for an induced character of radiation processes sufficiently improves the predictions of the standard theory. Moreover, the developed here theory of radio emission from non-uniform gas gives the radio spectra of extended sources, such as supernova remnants and radio galaxies, which are normally attributed to the synchrotron emission. It is important, in this aspect, that the synchrotron self-absorption produces a change in the polarization position angle across the spectral peak. No such a change was detected in gigahertz-peaked spectrum sources (Mutoh et al. 2002). Besides, the flat or sligh...

  13. Characterizing the radiation response of Cherenkov glass detectors with isotopic sources

    Energy Technology Data Exchange (ETDEWEB)

    Hayward, J P [University of Tennessee, Knoxville (UTK); Hobbs, C. L. [University of Tennessee, Knoxville (UTK); Bell, Zane W [ORNL; Boatner, Lynn A [ORNL; Johnson, Rose E [ORNL; Ramey, Joanne Oxendine [ORNL; Jellison Jr, Gerald Earle [ORNL; Lillard, Cole R [ORNL; Ramey, Lucas A [ORNL

    2012-01-01

    Abstract Cherenkov detectors are widely used for particle identification and threshold detectors in high-energy physics. Glass Cherenkov detectors that are sensitive to beta emissions originating from neutron activation have been demonstrated recently as a potential replacement for activation foils. In this work, we set the groundwork to evaluate large Cherenkov glass detectors for sensitivity to MeV photons through first understanding the measured response of small Cherenkov glass detectors to isotopic gamma-ray sources. Counting and pulse height measurements are acquired with reflected glass Cherenkov detectors read out with a photomultiplier tube. Simulation was used to inform our understanding of the measured results. This simulation included radioactive source decay, radiation interaction, Cherenkov light generation, optical ray tracing, and photoelectron production. Implications for the use of Cherenkov glass detectors to measure low energy gammaray response are discussed.

  14. Filter and window assemblies for high power insertion device synchrotron radiation sources

    International Nuclear Information System (INIS)

    The powerful beams of x-ray radiation generated by insertion devices at high power synchrotron facilities deposit substantial amounts of localized heat in the front end and optical components that they intercept. X-ray beams from undulator sources, in particular, are confined to very narrow solid angles and therefore impose very high absorbed heat fluxes. This paper is devoted to a detailed study of the design of windows for the Advanced Photon Source undulators and wigglers, emphasizing alternative design concepts, material considerations, and cooling techniques necessary for handling the high heat load of the insertion devices. Various designs are thermally and structurally analyzed by numerically simulating full-power operating conditions. This analysis also has relevance to the design and development of other beam line components which are subjected to the high heat loads of insertion devices

  15. Measurement of the energy and power radiated by a pulsed blackbody x-ray source.

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, Gordon Andrew; McDaniel, Dillon Heirman; Jorgenson, Roy E.; Warne, Larry Kevin; Dropinski, Steven Clark; Hanson, Donald L.; Johnson, William Arthur; York, Mathew William; Lewis, D.F. (International Specialty Products, Wayne , NJ); Korde, R. (International Radiation Detectors, Torrance, CA); Haslett, C.L. (Ktech Corporation, Albuquerque, NM); Wall, D.L. (Resonetics, Nashua, New hampshire); Ruggles, Laurence E.; Ramirez, L.E. (ATK Mission Research Corporation, Albuquerque, NM); Stygar, William A.; Porter, John Larry, Jr.; McKenney, John Lee; Bryce, Edwin Anthony; Cuneo, Michael Edward; Torres, Jose A.; Mills, Jerry Alan; Leeper, Ramon Joe; McGurn, John Stephen; Fehl, David Lee; Spielman, R. B. (International Specialty Products, Wayne , NJ); Pyle, John H. (Ktech Corporation, Albuquerque, NM); Mazarakis, Michael Gerrassimos; Ives, Harry Crockett, III (EG& G, Albuquerque, NM); Seamen, Johann F.; Simpson, Walter W.

    2006-02-01

    We have developed a diagnostic system that measures the spectrally integrated (i.e. the total) energy and power radiated by a pulsed blackbody x-ray source. The total-energy-and-power (TEP) diagnostic system is optimized for blackbody temperatures between 50 and 350 eV. The system can view apertured sources that radiate energies and powers as high as 2 MJ and 200 TW, respectively, and has been successfully tested at 0.84 MJ and 73 TW on the Z pulsed-power accelerator. The TEP system consists of two pinhole arrays, two silicon-diode detectors, and two thin-film nickel bolometers. Each of the two pinhole arrays is paired with a single silicon diode. Each array consists of a 38 x 38 square array of 10-{micro}m-diameter pinholes in a 50-{micro}m-thick tantalum plate. The arrays achromatically attenuate the x-ray flux by a factor of {approx}1800. The use of such arrays for the attenuation of soft x rays was first proposed by Turner and co-workers [Rev. Sci. Instrum. 70, 656 (1999)RSINAK0034-674810.1063/1.1149385]. The attenuated flux from each array illuminates its associated diode; the diode's output current is recorded by a data-acquisition system with 0.6-ns time resolution. The arrays and diodes are located 19 and 24 m from the source, respectively. Because the diodes are designed to have an approximately flat spectral sensitivity, the output current from each diode is proportional to the x-ray power. The nickel bolometers are fielded at a slightly different angle from the array-diode combinations, and view (without pinhole attenuation) the same x-ray source. The bolometers measure the total x-ray energy radiated by the source and--on every shot--provide an in situ calibration of the array-diode combinations. Two array-diode pairs and two bolometers are fielded to reduce random uncertainties. An analytic model (which accounts for pinhole-diffraction effects) of the sensitivity of an array-diode combination is presented.

  16. Measurement of the energy and power radiated by a pulsed blackbody x-ray source

    International Nuclear Information System (INIS)

    We have developed a diagnostic system that measures the spectrally integrated (i.e. the total) energy and power radiated by a pulsed blackbody x-ray source. The total-energy-and-power (TEP) diagnostic system is optimized for blackbody temperatures between 50 and 350 eV. The system can view apertured sources that radiate energies and powers as high as 2 MJ and 200 TW, respectively, and has been successfully tested at 0.84 MJ and 73 TW on the Z pulsed-power accelerator. The TEP system consists of two pinhole arrays, two silicon-diode detectors, and two thin-film nickel bolometers. Each of the two pinhole arrays is paired with a single silicon diode. Each array consists of a 38 x 38 square array of 10-(micro)m-diameter pinholes in a 50-(micro)m-thick tantalum plate. The arrays achromatically attenuate the x-ray flux by a factor of ∼1800. The use of such arrays for the attenuation of soft x rays was first proposed by Turner and co-workers [Rev. Sci. Instrum. 70, 656 (1999)RSINAK0034-674810.1063/1.1149385]. The attenuated flux from each array illuminates its associated diode; the diode's output current is recorded by a data-acquisition system with 0.6-ns time resolution. The arrays and diodes are located 19 and 24 m from the source, respectively. Because the diodes are designed to have an approximately flat spectral sensitivity, the output current from each diode is proportional to the x-ray power. The nickel bolometers are fielded at a slightly different angle from the array-diode combinations, and view (without pinhole attenuation) the same x-ray source. The bolometers measure the total x-ray energy radiated by the source and--on every shot--provide an in situ calibration of the array-diode combinations. Two array-diode pairs and two bolometers are fielded to reduce random uncertainties. An analytic model (which accounts for pinhole-diffraction effects) of the sensitivity of an array-diode combination is presented

  17. Astrophysical Ionizing Radiation and the Earth: A Brief Review and Census of Intermittent Intense Sources

    CERN Document Server

    Melott, Adrian L

    2011-01-01

    Cosmic radiation backgrounds are a constraint on life, and their distribution will affect the Galactic Habitable Zone. Life on Earth has developed in the context of these backgrounds, and characterizing event rates will elaborate the important influences. This in turn can be a base for comparison with other potential life-bearing planets. In this review we estimate the intensities and rates of occurrence of many kinds of strong radiation bursts by astrophysical entities ranging from gamma-ray bursts at cosmological distances to the Sun itself. Many of these present potential hazards to the biosphere: on timescales long compared with human history, the probability of an event intense enough to disrupt life on the land surface or in the oceans becomes large. We enumerate the known sources of radiation and characterize their intensities at the Earth and rates or upper limits on these quantities. When possible, we estimate a "lethal interval", our best estimate of how often a major extinction-level event is proba...

  18. Measurement, analysis and correction of the closed orbit distortion in Indus-2 synchrotron radiation source

    Indian Academy of Sciences (India)

    Riyasat Husain; A D Ghodke; Surendra Yadav; A C Holikatti; R P Yadav; P Fatnani; T A Puntambekar; P R Hannurkar

    2013-02-01

    The paper presents the measurement, analysis and correction of closed orbit distortion (COD) in Indus-2 at 550 MeV injection energy and 2 GeV synchrotron radiation user run energy. The measured COD was analysed and fitted to understand major sources of errors in terms of the effective quadrupole misalignments. The rms COD was corrected down to less than 0.6 mm in both horizontal and vertical planes. A golden orbit was set for the operating synchrotron radiation beamlines. With COD correction, the injection efficiency at 550 MeV was improved by ∼ 50% and the beam lifetime at 2 GeV was increased by ∼8 h. In this paper, the method of global COD correction based on singular value decomposition (SVD) of the orbit response matrix is described. Results for the COD correction in both horizontal and vertical planes at 550 MeV injection energy and at 2 GeV synchrotron radiation user run energy are discussed.

  19. Investigation of radiation streaming and maze design for the Taiwan Photon Source.

    Science.gov (United States)

    Sheu, Rong-Jiun; Liu, Joseph

    2010-04-01

    This study investigates the radiation streaming through the personnel access maze designed for the Taiwan Photon Source, with special interest in the characteristics of radiation fields along the labyrinth and the comparison of different estimation methods. The effect of maze orientation with respect to the beam direction has also been examined in detail. The FLUKA Monte Carlo code was used to simulate the radiation production and transport for a beam loss occurring near a typical three-legged maze. In addition, we have also tested three factorized approximation formulae for the neutron and gamma-ray attenuation in our maze design. It was found that Cossairt's expression fits better and can predict satisfactory results for the neutron attenuation along the maze. We accordingly proposed a set of fitting parameters used with Cossairt's formulae for estimating the gamma-ray attenuation in labyrinths for high-energy electron accelerators. The information presented here will be valuable for our further design revisions and may be useful to those performing similar studies. PMID:20220363

  20. International Standardization of the Clinical Dosimetry of Beta Radiation Brachytherapy Sources: Progress of an ISO Standard

    Science.gov (United States)

    Soares, Christopher

    2006-03-01

    In 2004 a new work item proposal (NWIP) was accepted by the International Organization for Standardization (ISO) Technical Committee 85 (TC85 -- Nuclear Energy), Subcommittee 2 (Radiation Protection) for the development of a standard for the clinical dosimetry of beta radiation sources used for brachytherapy. To develop this standard, a new Working Group (WG 22 - Ionizing Radiation Dosimetry and Protocols in Medical Applications) was formed. The standard is based on the work of an ad-hoc working group initiated by the Dosimetry task group of the Deutsches Insitiut für Normung (DIN). Initially the work was geared mainly towards the needs of intravascular brachytherapy, but with the decline of this application, more focus has been placed on the challenges of accurate dosimetry for the concave eye plaques used to treat ocular melanoma. Guidance is given for dosimetry formalisms, reference data to be used, calibrations, measurement methods, modeling, uncertainty determinations, treatment planning and reporting, and clinical quality control. The document is currently undergoing review by the ISO member bodies for acceptance as a Committee Draft (CD) with publication of the final standard expected by 2007. There are opportunities for other ISO standards for medical dosimetry within the framework of WG22.

  1. Response of a hybrid pixel detector (MEDIPIX3) to different radiation sources for medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Chumacero, E. Miguel; De Celis Alonso, B.; Martínez Hernández, M. I.; Vargas, G.; Moreno Barbosa, E., E-mail: emoreno.emb@gmail.com [Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Av. San Claudio y Rio Verde, Puebla (Mexico); Moreno Barbosa, F. [Hospital General del Sur Hospital de la Mujer, Puebla (Mexico)

    2014-11-07

    The development in semiconductor CMOS technology has enabled the creation of sensitive detectors for a wide range of ionizing radiation. These devices are suitable for photon counting and can be used in imaging and tomography X-ray diagnostics. The Medipix[1] radiation detection system is a hybrid silicon pixel chip developed for particle tracking applications in High Energy Physics. Its exceptional features (high spatial and energy resolution, embedded ultra fast readout, different operation modes, etc.) make the Medipix an attractive device for applications in medical imaging. In this work the energy characterization of a third-generation Medipix chip (Medipix3) coupled to a silicon sensor is presented. We used different radiation sources (strontium 90, iron 55 and americium 241) to obtain the response curve of the hybrid detector as a function of energy. We also studied the contrast of the Medipix as a measure of pixel noise. Finally we studied the response to fluorescence X rays from different target materials (In, Pd and Cd) for the two data acquisition modes of the chip; single pixel mode and charge summing mode.

  2. HAW simulation experiments with cobalt-60 radiation sources in the Asse salt mine

    International Nuclear Information System (INIS)

    The report describes the experimental work and the measured data of the joint German-American project for the HAW simulation experiment with cobalt-60 radiation sources in the Asse salt mine, covering the period up to the end of the third quarter 1986. The experiment is intended to yield information on the synergistic effects of heat and ionizing radiation on the salt rock under representative waste repository conditions. The investigations aim at the migration, release, and radiolytic decomposition of the water and gas components in the rock salt, and at the thermally induced strain and deformation processes. In addition, corrosion tests are planned to be made on various container test materials, and analyses of salt rock core samples for assessing the effect of heat and radiation on the rock. The report in hand presents all data obtained during the experiment. The results of the subsequent evaluation and verification studies will be presented in another report, the programme being given in an annex to the report in hand. (orig./RB)

  3. Design of an Yb-169 source optimized for gold nanoparticle-aided radiation therapy

    International Nuclear Information System (INIS)

    Purpose: To find an optimum design of a new high-dose rate ytterbium (Yb)-169 brachytherapy source that would maximize the dose enhancement during gold nanoparticle-aided radiation therapy (GNRT), while meeting practical constraints for manufacturing a clinically relevant brachytherapy source. Methods: Four different Yb-169 source designs were considered in this investigation. The first three source models had a single encapsulation made of one of the following materials: aluminum, titanium, and stainless steel. The last source model adopted a dual encapsulation design with an inner aluminum capsule surrounding the Yb-core and an outer titanium capsule. Monte Carlo (MC) simulations using the Monte Carlo N-Particle code version 5 (MCNP5) were conducted initially to investigate the spectral changes caused by these four source designs and the associated variations in macroscopic dose enhancement across the tumor loaded with gold nanoparticles (GNPs) at 0.7% by weight. Subsequent MC simulations were performed using the EGSnrc and NOREC codes to determine the secondary electron spectra and microscopic dose enhancement as a result of irradiating the GNP-loaded tumor with the MCNP-calculated source spectra. Results: Effects of the source filter design were apparent in the current MC results. The intensity-weighted average energy of the Yb-169 source varied from 108.9 to 122.9 keV, as the source encapsulation material changed from aluminum to stainless steel. Accordingly, the macroscopic dose enhancement calculated at 1 cm away from the source changed from 51.0% to 45.3%. The sources encapsulated by titanium and aluminum/titanium combination showed similar levels of dose enhancement, 49.3% at 1 cm, and average energies of 113.0 and 112.3 keV, respectively. While the secondary electron spectra due to the investigated source designs appeared to look similar in general, some differences were noted especially in the low energy region (<50 keV) of the spectra suggesting the

  4. Inner Radiation Belt Source of Helium and Heavy Hydrogen Nuclei Isotope

    Science.gov (United States)

    Galper, A. M.; Koldashov, S. V.; Leonov, A. A.; Mikhailov, V. V.

    Nuclear interactions between inner zone protons and atoms in the upper atmosphere provide the essential source of H and He isotopes nuclei in radiation belt. This paper reports specified calculations of these isotopes intensities from the various inner zone proton intensity models AP-8, CRRESPRO and SAMPEX/PET PSB97, the atmosphere drift-averaged composition and densities model MSIS-90, and cross sections for the interaction processes from the GNASH nuclear model code. To calculate drift-averaged densities and energy losses of secondaries the particles are traced in geomagnetic field according IGRF-95 model by numerical solution of motion equation. The calculations account for nuclear interactions kinematic along the whole trapped protons trajectories. The comparison with observational data from SAMPEX, CRRES, RESURS-04 and MITA satellites taken during different solar activity phases shows that the atmosphere is sufficient source for inner zone 4He, 3He, 2H and 3H for L-shell less than 1.3. The calculation model allows having the energy spectrum and angle distribution of light nuclear isotopes in inner radiation belt that can be used to evaluate SEU rates.

  5. Tandem-ESQ for Accelerator-Based BNCT

    International Nuclear Information System (INIS)

    A new ultrahigh-resolution photoemission electron microscope called PEEM3 is being developed and built at the Advanced Light Source (ALS). An electron mirror combined with a much-simplified magnetic dipole separator is to be used to provide simultaneous correction of spherical and chromatic aberrations. It is installed on an elliptically polarized undulator (EPU) beamline, and will be operated with very high spatial resolution and high flux to study the composition, structure, electric and magnetic properties of complex materials. The instrument has been designed and is described. The instrumental hardware is being deployed in 2 phases. The first phase is the deployment of a standard PEEM type microscope consisting of the standard linear array of electrostatic electron lenses. The second phase will be the installation of the aberration corrected upgrade to improve resolution and throughput. This paper describes progress as the instrument enters the commissioning part of the first phase

  6. Brown carbon aerosol in the North American continental troposphere: sources, abundance, and radiative forcing

    Science.gov (United States)

    Liu, J.; Scheuer, E.; Dibb, J.; Diskin, G. S.; Ziemba, L. D.; Thornhill, K. L.; Anderson, B. E.; Wisthaler, A.; Mikoviny, T.; Devi, J. J.; Bergin, M.; Perring, A. E.; Markovic, M. Z.; Schwarz, J. P.; Campuzano-Jost, P.; Day, D. A.; Jimenez, J. L.; Weber, R. J.

    2015-07-01

    Chemical components of organic aerosol (OA) selectively absorb light at short wavelengths. In this study, the prevalence, sources, and optical importance of this so-called brown carbon (BrC) aerosol component are investigated throughout the North American continental tropospheric column during a summer of extensive biomass burning. Spectrophotometric absorption measurements on extracts of bulk aerosol samples collected from an aircraft over the central USA were analyzed to directly quantify BrC abundance. BrC was found to be prevalent throughout the 1 to 12 km altitude measurement range, with dramatic enhancements in biomass-burning plumes. BrC to black carbon (BC) ratios, under background tropospheric conditions, increased with altitude, consistent with a corresponding increase in the absorption Ångström exponent (AAE) determined from a three-wavelength particle soot absorption photometer (PSAP). The sum of inferred BC absorption and measured BrC absorption at 365 nm was within 3 % of the measured PSAP absorption for background conditions and 22 % for biomass burning. A radiative transfer model showed that BrC absorption reduced top-of-atmosphere (TOA) aerosol forcing by ~ 20 % in the background troposphere. Extensive radiative model simulations applying this study background tropospheric conditions provided a look-up chart for determining radiative forcing efficiencies of BrC as a function of a surface-measured BrC : BC ratio and single scattering albedo (SSA). The chart is a first attempt to provide a tool for better assessment of brown carbon's forcing effect when one is limited to only surface data. These results indicate that BrC is an important contributor to direct aerosol radiative forcing.

  7. 3D Finite-Difference Modeling of Acoustic Radiation from Seismic Sources

    Science.gov (United States)

    Chael, E. P.; Aldridge, D. F.; Jensen, R. P.

    2013-12-01

    Shallow seismic events, earthquakes as well as explosions, often generate acoustic waves in the atmosphere observable at local or even regional distances. Recording both the seismic and acoustic signals can provide additional constraints on source parameters such as epicenter coordinates, depth, origin time, moment, and mechanism. Recent advances in finite-difference (FD) modeling methods enable accurate numerical treatment of wave propagation across the ground surface between the (solid) elastic and (fluid) acoustic domains. Using a fourth-order, staggered-grid, velocity-stress FD algorithm, we are investigating the effects of various source parameters on the acoustic (or infrasound) signals transmitted from the solid earth into the atmosphere. Compressional (P), shear (S), and Rayleigh waves all radiate some acoustic energy into the air at the ground surface. These acoustic wavefronts are typically conical in shape, since their phase velocities along the surface exceed the sound speed in air. Another acoustic arrival with a spherical wavefront can be generated from the vicinity of the epicenter of a shallow event, due to the strong vertical ground motions directly above the buried source. Images of acoustic wavefields just above the surface reveal the radiation patterns and relative amplitudes of the various arrivals. In addition, we compare the relative effectiveness of different seismic source mechanisms for generating acoustic energy. For point sources at a fixed depth, double-couples with almost any orientation produce stronger acoustic signals than isotropic explosions, due to higher-amplitude S and Rayleigh waves. Of course, explosions tend to be shallower than most earthquakes, which can offset the differences due to mechanism. Low-velocity material in the shallow subsurface acts to increase vertical seismic motions there, enhancing the coupling to acoustic waves in air. If either type of source breaks the surface (e.g., an earthquake with surface rupture

  8. John Adams Lecture | Accelerator-Based Neutrino Physics: Past, Present and Future by Kenneth Long | 8 December

    CERN Multimedia

    2014-01-01

    John Adams Lecture: Accelerator-Based Neutrino Physics: Past, Present and Future by Dr. Kenneth Long (Imperial College London & STFC).   Monday, 8 December 2014 from 2 p.m. to 4 p.m. at CERN ( 503-1-001 - Council Chamber ) Abstract: The study of the neutrino is the study of physics beyond the Standard Model. We now know that the neutrinos have mass and that neutrino mixing occurs causing neutrino flavour to oscillate as neutrinos propagate through space and time. Further, some measurements can be interpreted as hints for new particles known as sterile neutrinos. The measured values of the mixing parameters make it possible that the matter-antimatter (CP) symmetry may be violated through the mixing process. The consequences of observing CP-invariance violation in neutrinos would be profound. To discover CP-invariance violation will require measurements of exquisite precision. Accelerator-based neutrino sources are central to the future programme and advances in technique are required ...

  9. Radiation shielding analysis of consolidated container for spent sealed sources reflecting transportation regulation of type a package

    International Nuclear Information System (INIS)

    The sealed sources conditioning approach comprised the encapsulation of the source in a stainless steel capsule followed by placing the capsule in the cylindrical lead container containing 9 smaller hole for the stainless steel capsules and one big hole for large capsule for extra size sources. In case of high dose rates from gamma sources, placing the container inside a 200L steel drum filled with concrete. We decided that the package including the container is classified as Type A package for special form material according to Korea atomic law and IAEA safety standard series ST-1, This means that the maximum radiation dose rates at any point of the external surface shall not exceed 2 mSv/hr and, 0.1 mSv/hr at 1m from the surface for the shielding container, especially for strong gamma sources such as Ir-191, Cs-137 etc. In order to evaluate radiation shielding integrity for the containers and overpack, MCNP4b for shielding was used. In order to maximize containing radioactivity of spent sealed sources per the container considering allowable dose rates, we manufactured concrete mould the overpack only for radiation shielding which has similar dimension as typical DOT-17H drum. Finally, radiation shielding safety that meets Type A package for special form radioactive materials accomplished by the consolidated container itself and radiation dose from the container can be significantly reduced by adopting overpack shielding

  10. eBooking of beam-time over internet for beamlines of Indus synchrotron radiation sources

    International Nuclear Information System (INIS)

    Users from various research labs and academic institutes carry out experiments on beamlines of two Synchrotron Radiation Sources Indus-1 and Indus-2 available at RRCAT, Indore. To carry out experimental work on beamlines of both synchrotron radiation sources, beam-time is booked over Internet by the users of beamlines using user portal designed, developed and deployed over Internet. This portal has made the process of beamtime booking fast, hassle free and paperless as manual booking of beam-time for carrying out experiment on a particular beamline is cumbersome. The portal facilitates in-charge of Indus-1 and Indus-2 beamlines to keep track of users' records, work progress and other activities linked to experiments carried on beamlines. It is important to keep record and provide statistics about the usage of the beam lines from time-to-time. The user portal for e-booking of beam-time has been developed in-house using open source software development tools. Multi-step activities of users and beamline administrators are workflow based with seamless flow of information across various modules and fully authenticated using role based mechanism for different roles of software usage. The software is in regular use since November 2013 and has helped beamline in- charges in efficiently managing various activities related to user registration, booking of beam-time, booking of Guest House, Generation of Security permits, User feedback etc. Design concept, role based authentication mechanism and features provided by the web portal are discussed in detail in this paper. (author)

  11. Separation of radiated sound field components from waves scattered by a source under non-anechoic conditions

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Jacobsen, Finn

    2010-01-01

    A method of estimating the sound field radiated by a source under non-anechoic conditions has been examined. The method uses near field acoustic holography based on a combination of pressure and particle velocity measurements in a plane near the source for separating outgoing and ingoing wave...... components. The outgoing part of the sound field is composed of both radiated and scattered waves. The method compensates for the scattered components of the outgoing field on the basis of the boundary condition of the problem, exploiting the fact that the sound field is reconstructed very close...... to the source. Thus the radiated free-field component is estimated simultaneously with solving the inverse problem of reconstructing the sound field near the source. The method is particularly suited to cases in which the overall contribution of reflected sound in the measurement plane is significant....

  12. Repeated delayed onset cerebellar radiation injuries after linear accelerator-based stereotactic radiosurgery for vestibular schwannoma

    OpenAIRE

    Ujifuku, Kenta; Matsuo, Takayuki; Toyoda, Keisuke; Baba, Shiro; Okunaga, Tomohiro; Hayashi, Yukishige; Kamada, Kensaku; MORIKAWA, Minoru; Suyama, Kazuhiko; Nagata, Izumi; Hayashi, Nobuyuki

    2012-01-01

    A 63-year-old woman presented with right hearing disturbance and vertigo. Magnetic resonance (MR) imaging revealed the presence of right vestibular schwannoma (VS). Stereotactic radiosurgery (SRS) was performed with a tumor marginal dose of 14 Gy using two isocenters. She was followed up clinically and neuroradiologically using three-dimensional spoiled gradient-echo MR imaging. She experienced temporal neurological deterioration due to peritumoral edema in her right cerebellar peduncle and p...

  13. Radiation source reconstruction with known geometry and materials using the adjoint

    Energy Technology Data Exchange (ETDEWEB)

    Hykes, Joshua M.; Azmy, Yousry Y., E-mail: jmhykes@ncsu.edu, E-mail: yyazmy@ncsu.gov [Department of Nuclear Engineering, North Carolina State University, Raleigh, NC (United States)

    2011-07-01

    We present a method to estimate an unknown isotropic source distribution, in space and energy, using detector measurements when the geometry and material composition are known. The estimated source distribution minimizes the difference between the measured and computed responses of detectors located at a selected number of points within the domain. In typical methods, a forward flux calculation is performed for each source guess in an iterative process. In contrast, we use the adjoint flux to compute the responses. Potential applications of the proposed method include determining the distribution of radio-contaminants following a nuclear event, monitoring the flow of radioactive fluids in pipes to determine hold-up locations, and retroactive reconstruction of radiation fields using workers' detectors' readings. After presenting the method, we describe a numerical test problem to demonstrate the preliminary viability of the method. As expected, using the adjoint flux reduces the number of transport solves to be proportional to the number of detector measurements, in contrast to methods using the forward flux that require a typically larger number proportional to the number of spatial mesh cells. (author)

  14. Radiation source reconstruction with known geometry and materials using the adjoint

    International Nuclear Information System (INIS)

    We present a method to estimate an unknown isotropic source distribution, in space and energy, using detector measurements when the geometry and material composition are known. The estimated source distribution minimizes the difference between the measured and computed responses of detectors located at a selected number of points within the domain. In typical methods, a forward flux calculation is performed for each source guess in an iterative process. In contrast, we use the adjoint flux to compute the responses. Potential applications of the proposed method include determining the distribution of radio-contaminants following a nuclear event, monitoring the flow of radioactive fluids in pipes to determine hold-up locations, and retroactive reconstruction of radiation fields using workers' detectors' readings. After presenting the method, we describe a numerical test problem to demonstrate the preliminary viability of the method. As expected, using the adjoint flux reduces the number of transport solves to be proportional to the number of detector measurements, in contrast to methods using the forward flux that require a typically larger number proportional to the number of spatial mesh cells. (author)

  15. Assessment of dose contribution to population exposure from the radiation sources in the alienated Chernobyl zone

    International Nuclear Information System (INIS)

    The main dose load of Ukrainian population is caused by radionuclide-contamination of country territories, located outside the alienated zone, following Chernobyl accident. Besides, much attention could be devoted to the contribution of dose load on population, received from the radioactivity sources that were transferred out from the zone after accident. Present research and analysis of the available documents reflecting the transfer of radioactivity from the alienated zone, provided the estimates of dose load on population, resulting from transfer of the radioactivity sources via following channels: (1) direct surface flow; (2) underground waters; (3) wind-powdered route; (4) transfer with hydrobionts; (5) transfer during irrigation; (6) biogenic route; (7) transport routes and (8) route during wood transportation. Dynamics of radiation transfer through each channel was also studied for the post-accident period. Specific gravity of radioactivity transfer is determined in relation to dose load on Ukrainian population in different regions, in particular, in Dnipro river basin. The perspectives of radioactivity transfer via each of studied channels and its role in dose load on population were also analyzed. On the basis of present results the recommendations on possible arrangements are working out that aimed to reduce the dose contribution in population exposure by radioactivity source transfer from the alienated zone via channels that stipulate the largest dose loads and collective doses

  16. Environmental and source monitoring for purposes of radiation protection. Safety guide

    International Nuclear Information System (INIS)

    IAEA takes seriously the enduring challenge for users and regulators everywhere: that of ensuring a high level of safety in the use of nuclear materials and radiation sources around the world. Their continuing utilization for the benefit of humankind must be managed in a safe manner, and the IAEA safety standards are designed to facilitate the achievement of that goal

  17. Accelerator-based neutron source using a cold deuterium target with degenerate electrons

    Directory of Open Access Journals (Sweden)

    R. E. Phillips

    2013-07-01

    Full Text Available A neutron generator is considered in which a beam of tritons is incident on a hypothetical cold deuterium target with degenerate electrons. The energy efficiency of neutron generation is found to increase substantially with electron density. Recent reports of potential targets are discussed.

  18. Design of an accelerator-based neutron source for neutron capture therapy

    International Nuclear Information System (INIS)

    The boron neutron capture therapy is mainly suited in the treatment of some tumor kinds which revealed ineffective to the traditional radiotherapy. In order to take advantage of such a therapeutic modality in hospital environments, neutron beams of suitable energy and flux levels provided by compact size facilities are needed. The advantages and drawbacks of several neutron beams are here analysed in terms of therapeutic gains. In detail the GEANT-3/MICAP simulations show that high tumor control probability, with sub-lethal dose at healthy tissues, can be achieved by using neutron beams of few keV energy having a flux of about 109 neutrons/(cm2 s). To produce such a neutron beam, the feasibility of a proton accelerator is investigated. In particular an appropriate choice of the radiofrequency parameters (modulation, efficiency of acceleration, phase shift, etc.) allows the development of relatively compact accelerators, having a proton beam current of 30 mA and an energy of 2 MeV, which could eventually lead to setting up of hospital-based neutron facilities.

  19. Legal sources covering radiation protection in the EC countries, EFTA and the USA

    International Nuclear Information System (INIS)

    This paper covers the following subjects: Areas of application of the Radiation Protection Law, international legal basis, constitutional law and radiation protection, standard addresses, principles, monitoring regulations, in-company radiation protection organisation, law and technology, individual regulation areas. refs

  20. LIGHT SOURCE: Conceptual design of Hefei advanced light source

    Science.gov (United States)

    Li, Wei-Min; Wang, Lin; Feng, Guang-Yao; Zhang, Shan-Cai; Wu, Cong-Feng; Xu, Hong-Liang; Liu, Zu-Ping

    2009-06-01

    The conceptual of Hefei Advanced Light Source, which is an advanced VUV and Soft X-ray source, was developed at NSRL of USTC. According to the synchrotron radiation user requirements and the trends of SR source development, some accelerator-based schemes were considered and compared; furthermore storage ring with ultra low emittance was adopted as the baseline scheme of HALS. To achieve ultra low emittance, some focusing structures were studied and optimized in the lattice design. Compromising of emittance, on-momentum and off-momentum dynamic aperture and ring scale, five bend acromat (FBA) was employed. In the preliminary design of HALS, the emittance was reduced to sub nm · rad, thus the radiation up to water window has full lateral coherence. The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders. The HALS should be one of the most advanced synchrotron radiation light sources in the world.

  1. Order n.02-059 /P-RM of 05 juin 2002 setting up radioprotection et safety of ionizing radiation sources

    International Nuclear Information System (INIS)

    This order establishes the legal framework of radioprotection and safety of ionizing radiation sources in Mali. The scope as well as the definition of some main terms are given. The basis principles of radioprotection against ionizing radiation sources are defined. Instructions in uses of ionizing radiations, penal provisions are outlined

  2. Shielding NSLS-II light source: Importance of geometry for calculating radiation levels from beam losses

    Science.gov (United States)

    Kramer, S. L.; Ghosh, V. J.; Breitfeller, M.; Wahl, W.

    2016-11-01

    Third generation high brightness light sources are designed to have low emittance and high current beams, which contribute to higher beam loss rates that will be compensated by Top-Off injection. Shielding for these higher loss rates will be critical to protect the projected higher occupancy factors for the users. Top-Off injection requires a full energy injector, which will demand greater consideration of the potential abnormal beam miss-steering and localized losses that could occur. The high energy electron injection beam produces significantly higher neutron component dose to the experimental floor than a lower energy beam injection and ramped operations. Minimizing this dose will require adequate knowledge of where the miss-steered beam can occur and sufficient EM shielding close to the loss point, in order to attenuate the energy of the particles in the EM shower below the neutron production threshold (energy on the bulk shield walls and thereby the dose penetrating the shield walls. Designing supplemental shielding near the loss point using the analytic shielding model is shown to be inadequate because of its lack of geometry specification for the EM shower process. To predict the dose rates outside the tunnel requires detailed description of the geometry and materials that the beam losses will encounter inside the tunnel. Modern radiation shielding Monte-Carlo codes, like FLUKA, can handle this geometric description of the radiation transport process in sufficient detail, allowing accurate predictions of the dose rates expected and the ability to show weaknesses in the design before a high radiation incident occurs. The effort required to adequately define the accelerator geometry for these codes has been greatly reduced with the implementation of the graphical interface of FLAIR to FLUKA. This made the effective shielding process for NSLS-II quite accurate and reliable. The principles used to provide supplemental shielding to the NSLS-II accelerators and

  3. Photostimulated phosphor based image plate detection system for HRVUV beamline at Indus-1 synchrotron radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Haris, K. [Department of Physics, Aligarh Muslim University, Aligarh 202002 (India); Singh, Param Jeet [Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Shastri, Aparna, E-mail: ashastri@barc.gov.in [Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Sunanda, K.; Babita, K.; Rao, S.V.N. Bhaskara [Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Ahmad, Shabbir; Tauheed, A. [Department of Physics, Aligarh Muslim University, Aligarh 202002 (India)

    2014-12-11

    A high resolution vacuum ultraviolet (HRVUV) beamline based on a 6.65 m off-plane Eagle spectrometer is in operation at the Indus-1 synchrotron radiation source, RRCAT, Indore, India. To facilitate position sensitive detection and fast spectral recording, a new BaFBr:Eu{sup 2+} phosphor based image plate (IP) detection system interchangeable with the existing photomultiplier (PMT) scanning system has been installed on this beamline. VUV photoabsorption studies on Xe, O{sub 2}, N{sub 2}O and SO{sub 2} are carried out to evaluate the performance of the IP detection system. An FWHM of ∼0.5 Å is achieved for the Xe atomic line at 1469.6 Å. Reproducibility of spectra is found to be within the experimental resolution. Compared to the PMT scanning system, the IP shows several advantages in terms of sensitivity, recording time and S/N ratio, which are highlighted in the paper. This is the first report of incorporation of an IP detection system in a VUV beamline using synchrotron radiation. Commissioning of the new detection system is expected to greatly enhance the utilization of the HRVUV beamline as a number of spectroscopic experiments which require fast recording times combined with a good signal to noise ratio are now feasible. - Highlights: • Incorporation of an image plate detection system on HRVUV beamline at Indus-1. • Design and fabrication of mounting mechanisms, performance evaluation of new system. • Photoabsorption spectra of Xe, O{sub 2}, SO{sub 2} and N{sub 2}O recorded in the region 1150–2300 Å. • Sensitivity, wavelength coverage, reproducibility and resolution of IP demonstrated. • First report of IP detector for VUV photoabsorption using synchrotron radiation.

  4. Exemption of radiation sources and practices from regulatory control: Interim report

    International Nuclear Information System (INIS)

    This document is an interim report on progress at the IAEA on exemption principles and their application to low-level radioactive waste disposal. In the first part of the document the general principles for the exemption of radiation sources and practices from regulatory control are described. The exempt quantities of low-level radioactive wastes for disposal to municipal landfill or by incineration including methods for their derivation and generic values are contained in the second part of the document. In the appendices the individual effective dose equivalents and committed effective dose equivalents by pathway for waste concentrations of 1 Bq.g-1 and some quoted limits from the literature on dust concentrations at the outlet of municipal waste incinerators are estimated

  5. The Advanced Photon Source: A national synchrotron radiation research facility at Argonne National Laboratory

    International Nuclear Information System (INIS)

    The vision of the APS sprang from prospective users, whose unflagging support the project has enjoyed throughout the decade it has taken to make this facility a reality. Perhaps the most extraordinary aspect of synchrotron radiation research, is the extensive and diverse scientific makeup of the user community. From this primordial soup of scientists exchanging ideas and information, come the collaborative and interdisciplinary accomplishments that no individual alone could produce. So, unlike the solitary Roentgen, scientists are engaged in a collective and dynamic enterprise with the potential to see and understand the structures of the most complex materials that nature or man can produce--and which underlie virtually all modern technologies. This booklet provides scientists and laymen alike with a sense of both the extraordinary history of x-rays and the knowledge they have produced, as well as the potential for future discovery contained in the APS--a source a million million times brighter than the Roentgen tube

  6. The Radiation Source ELBE and its Research Program in Nuclear Physics

    International Nuclear Information System (INIS)

    The new radiation source 'Strahlungsquelle ELBE' at the Forschungszentrum Rossendorf (FZR) near Dresden, Germany, is a user facility that utilizes a superconducting linear accelerator to produce various secondary beams for experiments in nuclear science, solid state physics, materials research, environmental chemistry and in the life sciences. The high brilliance electron beam of up to 40 MeV and 1 mA (cw) is mainly used to drive free electron lasers producing infrared light in the 5-150 μm wavelength region. Additionally, polarized MeV-Bremsstrahlung and X-rays from electron channeling are available, facilities for neutron and positron production are under construction. The talk outlines the ongoing research activities at ELBE with special attention to the nuclear resonance fluorescence experiments

  7. The Advanced Photon Source: A national synchrotron radiation research facility at Argonne National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The vision of the APS sprang from prospective users, whose unflagging support the project has enjoyed throughout the decade it has taken to make this facility a reality. Perhaps the most extraordinary aspect of synchrotron radiation research, is the extensive and diverse scientific makeup of the user community. From this primordial soup of scientists exchanging ideas and information, come the collaborative and interdisciplinary accomplishments that no individual alone could produce. So, unlike the solitary Roentgen, scientists are engaged in a collective and dynamic enterprise with the potential to see and understand the structures of the most complex materials that nature or man can produce--and which underlie virtually all modern technologies. This booklet provides scientists and laymen alike with a sense of both the extraordinary history of x-rays and the knowledge they have produced, as well as the potential for future discovery contained in the APS--a source a million million times brighter than the Roentgen tube.

  8. Initial feasibility study of a dedicated synchrotron radiation light source for ultrafast X-ray science

    International Nuclear Information System (INIS)

    We present an initial feasibility summary of a femtosecond synchrotron radiation x-ray source based on a flat-beam rf gun and a recirculating superconducting linac that provides beam to an array of undulators and bend magnets. Optical pulse durations of < 100 fs are obtained by a combination of electron pulse compression, transverse temporal correlation of the electrons, and x-ray pulse compression. After an introduction and initial scientific motivation, we cover the following aspects of the design: layout and lattice, ultra-fast x-ray pulse production, flat electron-beam production, the rf gun, rf systems, cryogenic systems, collective effects, photon production, and synchronization of x-ray and laser pulses. We conclude with a summary of issues and areas of development that remain to be addressed

  9. Combined Hyperthermia and Photodynamic Therapy Using a Sub-THz Gyrotron as a Radiation Source

    Science.gov (United States)

    Miyoshi, Norio; Idehara, Toshitaka; Khutoryan, Eduard; Fukunaga, Yukihiro; Bibin, Andriana Bintang; Ito, Shinji; Sabchevski, Svilen Petrov

    2016-08-01

    In this paper, we present results of a hyperthermia treatment of malignant tumors using a gyrotron as a radiation source for heating of the cancerous tissue. They clearly demonstrate the efficiency of the irradiation by sub-THz waves, which leads to steady decrease of the volume of the tumor and finally to its disappearance. A combination of hyperthermia and photodynamic therapy (PDT) that utilizes a novel multifunctional photosensitizer has also been explored. In the latter case, the results are even more convincing and promising. In particular, while after a hyperthermia treatment sometimes a regrowth of the tumor is being observed, in the case of combined hyperthermia and PDT such regrowth has never been noticed. Another combined therapy is based on a preheating of the tumor by gyrotron radiation to temperatures lower than the hyperthermia temperature of 43 °C and followed then by PDT. The results show that such combination significantly increases the efficiency of the treatment. We consider this phenomenon as a synergy effect since it is absent when hyperthermia and PDT are applied separately, and manifests itself only when both methods are combined.

  10. Evaluation of ozone concentration for a white beam line hutch at Indus-2 synchrotron radiation source

    International Nuclear Information System (INIS)

    In the synchrotron radiation source Indus-2, 26 synchrotron radiation beam lines are planned, out of which 7 beam lines are operational and several are in installation stage. For carrying out experiments, SR beam is brought out to air through the beam lines (which are housed in shielded hutches). Due to the interaction of SR with air, ozone is produced, which is a noxious gas and is hazardous, if inhaled in excess. The production of ozone is high in white beam lines in comparison with pink and monochromatic beam lines. In the present paper ozone generation for a white beam line of Indus-2 is estimated. The ozone production rate, saturation concentration, ventilation rate and delay time are also estimated. The saturation concentration of ozone for the white beam line (energy dispersive X-ray diffraction beam line) BL-11 was found to be 0.965 ppm for 100 cm interaction path length and 51.45 m3 hutch volume without any ventilation. The paper presents the details of the calculation and the results. (author)

  11. The Creation and Propagation of Radiation: Fields Inside and Outside of Sources

    CERN Document Server

    Olbert, Stanislaw; Price, Richard H

    2011-01-01

    We present a new algorithm for computing the electromagnetic fields of currents inside and outside of finite current sources, for arbitrary time variations in the currents. Unexpectedly, we find that our solutions for these fields are free of the concepts of differential calculus, in that our solutions only involve the currents and their time integrals, and do not involve the time derivatives of the currents. As examples, we give the solutions for two configurations of current: a planar solenoid and a rotating spherical shell carrying a uniform charge density. For slow time variations in the currents, we show that our general solutions reduce to the standard expressions for the fields in classic magnetic dipole radiation. In the limit of extremely fast turn-on of the currents, we show that for our general solutions the amount of energy radiated is exactly equal to the magnetic energy stored in the static fields a long time after current creation. We give three associated problem statements which can be used i...

  12. Estimate on external effective doses received by the Iranian population from environmental gamma radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Roozitalab, J.; Reza deevband, M.; Rastkhah, N. [National Radiation Protection Dept. Atomic Energy Organization (Iran, Islamic Republic of); Sohrabi, M. [Intenatinal atomic Energy Agency, Vienna (Austria)

    2006-07-01

    Concentration of natural radioactive materials, especially available U 238, Ra 226, Th 232, and K 40 in construction materials and soil, as well as absorb dose from cosmic rays, is the most important source of the people for effective doses from the environment radiation. In order to evaluate external effective dose, it has been carried out more than 1000 measurements in 36 cities by sensitive dosimeters to environmental gamma radiation for indoor and outdoor conditions in residential areas; which its results show that range of gamma exposure for inside of buildings in Iran is 8.7-20.5 {mu}R/h, and outdoor environments of different cities is 7.9-20.6 {mu}R/h, which their mean value are 14.33 and 12.62 {mu}R/h respectively. Meanwhile, it has been estimated that beam-absorbing ratio between indoor and outdoor in measured environments is 1.55, except contribution of cosmic rays. This studies show that average effective dose for each Iranian person from environmental gamma is 96.9 n Sv/h, and annually effective dose for every person is 0.848 mSv. (authors)

  13. Photostimulated phosphor based image plate detection system for HRVUV beamline at Indus-1 synchrotron radiation source

    CERN Document Server

    Haris, K; Shastri, Aparna; K., Sunanda; K., Babita; Rao, S V N Bhaskara; Ahmad, Shabbir; Tauheed, A

    2014-01-01

    A high resolution vacuum ultraviolet (HRVUV) beamline based on a 6.65 meter off-plane Eagle spectrometer is in operation at the Indus-1 synchrotron radiation source, RRCAT, Indore, India. To facilitate position sensitive detection and fast spectral recording, a new BaFBr:Eu2+ phosphor based image plate (IP) detection system interchangeable with the existing photomultiplier (PMT) scanning system has been installed on this beamline. VUV photoabsorption studies on Xe, O2, N2O and SO2 are carried out to evaluate the performance of the IP detection system. An FWHM of ~ 0.5 {\\AA} is achieved for the Xe atomic line at 1469.6 {\\AA}. Reproducibility of spectra is found to be within the experimental resolution. Compared to the PMT scanning system, the IP shows several advantages in terms of sensitivity, recording time and S/N ratio, which are highlighted in the paper. This is the first report of incorporation of an IP detection system in a VUV beamline using synchrotron radiation. Commissioning of the new detection sys...

  14. Open-Source Radiation Exposure Extraction Engine (RE3) with Patient-Specific Outlier Detection.

    Science.gov (United States)

    Weisenthal, Samuel J; Folio, Les; Kovacs, William; Seff, Ari; Derderian, Vana; Summers, Ronald M; Yao, Jianhua

    2016-08-01

    We present an open-source, picture archiving and communication system (PACS)-integrated radiation exposure extraction engine (RE3) that provides study-, series-, and slice-specific data for automated monitoring of computed tomography (CT) radiation exposure. RE3 was built using open-source components and seamlessly integrates with the PACS. RE3 calculations of dose length product (DLP) from the Digital imaging and communications in medicine (DICOM) headers showed high agreement (R (2) = 0.99) with the vendor dose pages. For study-specific outlier detection, RE3 constructs robust, automatically updating multivariable regression models to predict DLP in the context of patient gender and age, scan length, water-equivalent diameter (D w), and scanned body volume (SBV). As proof of concept, the model was trained on 811 CT chest, abdomen + pelvis (CAP) exams and 29 outliers were detected. The continuous variables used in the outlier detection model were scan length (R (2)  = 0.45), D w (R (2) = 0.70), SBV (R (2) = 0.80), and age (R (2) = 0.01). The categorical variables were gender (male average 1182.7 ± 26.3 and female 1047.1 ± 26.9 mGy cm) and pediatric status (pediatric average 710.7 ± 73.6 mGy cm and adult 1134.5 ± 19.3 mGy cm). PMID:26644157

  15. Gravitational Radiation from Post-Newtonian Sources and Inspiralling Compact Binaries

    Directory of Open Access Journals (Sweden)

    Luc Blanchet

    2014-02-01

    Full Text Available To be observed and analyzed by the network of gravitational wave detectors on ground (LIGO, VIRGO, etc. and by the future detectors in space (eLISA, etc., inspiralling compact binaries -- binary star systems composed of neutron stars and/or black holes in their late stage of evolution -- require high-accuracy templates predicted by general relativity theory. The gravitational waves emitted by these very relativistic systems can be accurately modelled using a high-order post-Newtonian gravitational wave generation formalism. In this article, we present the current state of the art on post-Newtonian methods as applied to the dynamics and gravitational radiation of general matter sources (including the radiation reaction back onto the source and inspiralling compact binaries. We describe the post-Newtonian equations of motion of compact binaries and the associated Lagrangian and Hamiltonian formalisms, paying attention to the self-field regularizations at work in the calculations. Several notions of innermost circular orbits are discussed. We estimate the accuracy of the post-Newtonian approximation and make a comparison with numerical computations of the gravitational self-force for compact binaries in the small mass ratio limit. The gravitational waveform and energy flux are obtained to high post-Newtonian order and the binary's orbital phase evolution is deduced from an energy balance argument. Some landmark results are given in the case of eccentric compact binaries -- moving on quasi-elliptical orbits with non-negligible eccentricity. The spins of the two black holes play an important role in the definition of the gravitational wave templates. We investigate their imprint on the equations of motion and gravitational wave phasing up to high post-Newtonian order (restricting to spin-orbit effects which are linear in spins, and analyze the post-Newtonian spin precession equations as well as the induced precession of the orbital plane.

  16. Guide to beamline radiation shielding design at the Advanced Photon Source

    International Nuclear Information System (INIS)

    This document is concerned with the general requirements for radiation shielding common to most Advanced Photon Source (APS) users. These include shielding specifications for hutches, transport, stops, and shutters for both white and monochromatic beams. For brevity, only the results of calculations are given in most cases. So-called open-quotes special situationsclose quotes are not covered. These include beamlines with white beam mirrors for low-pass energy filters (open-quotes pink beamsclose quotes), extremely wide band-pass monochromators (multilayers), or novel insertion devices. These topics are dependent on beamline layout and, as such, are not easily generalized. Also, many examples are given for open-quotes typicalclose quotes hutches or other beamline components. If a user has components that differ greatly from those described, particular care should be taken in following these guidelines. Users with questions on specific special situations should address them to the APS User Technical Interface. Also, this document does not cover specifics on hutch, transport, shutter, and stop designs. Issues such as how to join hutch panels, floor-wall interfaces, cable feed-throughs, and how to integrate shielding into transport are covered in the APS Beamline Standard Components Handbook. It is a open-quotes living documentclose quotes and as such reflects the improvements in component design that are ongoing. This document has the following content. First, the design criteria will be given. This includes descriptions of some of the pertinent DOE regulations and policies, as well as brief discussions of abnormal situations, interlocks, local shielding, and storage ring parameters. Then, the various sources of radiation on the experimental floor are discussed, and the methods used to calculate the shielding are explained (along with some sample calculations). Finally, the shielding recommendations for different situations are given and discussed

  17. Terahertz Coherent Synchrotron Radiation from Femtosecond Laser Modulation of the Electron Beam at the Advanced Light Source

    OpenAIRE

    Byrd, John M.; Hao, Zhao; Martin, Michael C.; Robin, David S.; Sannibale, Fernando; Schoenlein, Robert W.; Zholents, Alexander A.; Zolotorev, Max S.

    2005-01-01

    At the Advanced Light Source (ALS), the 'femtoslicing' beamline is in operation since 1999 for the production of x-ray synchrotron radiation pulses with femtosecond duration. The mechanism used for generating the short x-ray pulses induces at the same time temporary structures in the electron bunch longitudinal distribution with very short characteristic length. Such structures emit intense coherent synchrotron radiation (CSR) in the terahertz frequency range. These CSR pulses were first...

  18. The statistical distributed source boundary point method to calculate the acoustic radiation from the random vibrating body

    Institute of Scientific and Technical Information of China (English)

    WANGXiufeng; CHENXinzhao; LIUZhao

    2003-01-01

    The statistical distributed source boundary point method (SDSBPM) put forward is applied to calculate the acoustic radiation from the random vibrating body. A detailed description of this method is presented. A test for the SDSBPM is carried out through the random vibrating sphere and the random vibrating cuboid. An experiment on the exterior acoustic radiation of a random vibrating simulation axial box of the lathe tool is performed in a semi-anechoic chamber.

  19. Analysis of accelerator based neutron spectra for BNCT using proton recoil spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wielopolski, L.; Ludewig, H.; Powell, J.R.; Raparia, D.; Alessi, J.G.; Lowenstein, D.I.

    1999-03-01

    Boron Neutron Capture Therapy (BNCT) is a promising binary treatment modality for high-grade primary brain tumors (glioblastoma multiforme, GM) and other cancers. BNCT employs a boron-10 containing compound that preferentially accumulates in the cancer cells in the brain. Upon neutron capture by {sup 10}B energetic alpha particles and triton released at the absorption site kill the cancer cell. In order to gain penetration depth in the brain Fairchild proposed, for this purpose, the use of energetic epithermal neutrons at about 10 keV. Phase 1/2 clinical trials of BNCT for GM are underway at the Brookhaven Medical Research Reactor (BMRR) and at the MIT Reactor, using these nuclear reactors as the source for epithermal neutrons. In light of the limitations of new reactor installations, e.g. cost, safety and licensing, and limited capability for modulating the reactor based neutron beam energy spectra, alternative neutron sources are being contemplated for wider implementation of this modality in a hospital environment. For example, accelerator based neutron sources offer the possibility of tailoring the neutron beams, in terms of improved depth-dose distributions, to the individual and offer, with relative ease, the capability of modifying the neutron beam energy and port size. In previous work new concepts for compact accelerator/target configuration were published. In this work, using the Van de Graaff accelerator the authors have explored different materials for filtering and reflecting neutron beams produced by irradiating a thick Li target with 1.8 to 2.5 MeV proton beams. However, since the yield and the maximum neutron energy emerging from the Li-7(p,n)Be-7 reaction increase with increase in the proton beam energy, there is a need for optimization of the proton energy versus filter and shielding requirements to obtain the desired epithermal neutron beam. The MCNP-4A computer code was used for the initial design studies that were verified with benchmark

  20. ANALYSIS OF ACCELERATOR BASED NEUTRON SPECTRA FOR BNCT USING PROTON RECOIL SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    WIELOPOLSKI,L.; LUDEWIG,H.; POWELL,J.R.; RAPARIA,D.; ALESSI,J.G.; LOWENSTEIN,D.I.

    1998-11-06

    Boron Neutron Capture Therapy (BNCT) is a promising binary treatment modality for high-grade primary brain tumors (glioblastoma multiforme, GM) and other cancers. BNCT employs a boron-10 containing compound that preferentially accumulates in the cancer cells in the brain. Upon neutron capture by {sup 10}B energetic alpha particles and triton released at the absorption site kill the cancer cell. In order to gain penetration depth in the brain Fairchild proposed, for this purpose, the use of energetic epithermal neutrons at about 10 keV. Phase I/II clinical trials of BNCT for GM are underway at the Brookhaven Medical Research Reactor (BMRR) and at the MIT Reactor, using these nuclear reactors as the source for epithermal neutrons. In light of the limitations of new reactor installations, e.g. cost, safety and licensing, and limited capability for modulating the reactor based neutron beam energy spectra alternative neutron sources are being contemplated for wider implementation of this modality in a hospital environment. For example, accelerator based neutron sources offer the possibility of tailoring the neutron beams, in terms of improved depth-dose distributions, to the individual and offer, with relative ease, the capability of modifying the neutron beam energy and port size. In previous work new concepts for compact accelerator/target configuration were published. In this work, using the Van de Graaff accelerator the authors have explored different materials for filtering and reflecting neutron beams produced by irradiating a thick Li target with 1.8 to 2.5 MeV proton beams. However, since the yield and the maximum neutron energy emerging from the Li-7(p,n)Be-7 reaction increase with increase in the proton beam energy, there is a need for optimization of the proton energy versus filter and shielding requirements to obtain the desired epithermal neutron beam. The MCNP-4A computer code was used for the initial design studies that were verified with benchmark

  1. An accelerator-based epithermal neutron beam design for BNCT and dosimetric evaluation using a voxel head phantom.

    Science.gov (United States)

    Lee, Deok-jae; Han, Chi Young; Park, Sung Ho; Kim, Jong Kyung

    2004-01-01

    The beam shaping assembly design has been investigated in order to improve the epithermal neutron beam for accelerator-based boron neutron capture therapy in intensity and quality, and dosimetric evaluation for the beams has been performed using both mathematical and voxel head phantoms with MCNP runs. The neutron source was assumed to be produced from a conventional 2.5 MeV proton accelerator with a thick (7)Li target. The results indicate that it is possible to enhance epithermal neutron flux remarkably as well as to embody a good spectrum shaping to epithermal neutrons only with the proper combination of moderator and reflector. It is also found that a larger number of thermal neutrons can reach deeply into the brain and, therefore, can reduce considerably the treatment time for brain tumours. Consequently, the epithermal neutron beams designed in this study can treat more effectively deep-seated brain tumours.

  2. An assessment of the effects of radiation on permanent magnet material in the ALS [Advanced Light Source] insertion devices

    International Nuclear Information System (INIS)

    Electrons that are lost from the beam during normal operation of a synchrotron radiation source and during a beam dump at the end of a run produce both ionizing radiation and neutrons. This radiation has the potential for damaging sensitive materials, in particular those that need to be very close to the beam. The wigglers and undulators for the Advanced Light Source (ALS) at LBL will use magnetic materials such as the very high performance neodymium-iron-boron, which will be as close as 1 cm away from the electron beam during operation. This material, which is preferred because of its high remanence, is known to be more sensitive to radiation than some other magnetic materials. Simple energy loss estimates and the EGS4 code were used to estimate the radiation levels in the ALS insertion devices in the regions of the magnetic materials. The radiation levels were estimated for both aluminum and stainless steel vacuum chambers to determine if one would provide significantly better shielding. We conclude that Nd-Fe-B can be used in the ALS insertion devices and that there is little difference in the radiation levels for aluminum and stainless vacuum vessels. 8 refs., 7 figs., 1 tab

  3. A robust hypothesis test for the sensitive detection of constant speed radiation moving sources

    International Nuclear Information System (INIS)

    Radiation Portal Monitors are deployed in linear networks to detect radiological material in motion. As a complement to single and multichannel detection algorithms, inefficient under too low signal-to-noise ratios, temporal correlation algorithms have been introduced. Test hypothesis methods based on empirically estimated mean and variance of the signals delivered by the different channels have shown significant gain in terms of a tradeoff between detection sensitivity and false alarm probability. This paper discloses the concept of a new hypothesis test for temporal correlation detection methods, taking advantage of the Poisson nature of the registered counting signals, and establishes a benchmark between this test and its empirical counterpart. The simulation study validates that in the four relevant configurations of a pedestrian source carrier under respectively high and low count rate radioactive backgrounds, and a vehicle source carrier under the same respectively high and low count rate radioactive backgrounds, the newly introduced hypothesis test ensures a significantly improved compromise between sensitivity and false alarm. It also guarantees that the optimal coverage factor for this compromise remains stable regardless of signal-to-noise ratio variations between 2 and 0.8, therefore allowing the final user to parametrize the test with the sole prior knowledge of background amplitude

  4. A robust hypothesis test for the sensitive detection of constant speed radiation moving sources

    Science.gov (United States)

    Dumazert, Jonathan; Coulon, Romain; Kondrasovs, Vladimir; Boudergui, Karim; Moline, Yoann; Sannié, Guillaume; Gameiro, Jordan; Normand, Stéphane; Méchin, Laurence

    2015-09-01

    Radiation Portal Monitors are deployed in linear networks to detect radiological material in motion. As a complement to single and multichannel detection algorithms, inefficient under too low signal-to-noise ratios, temporal correlation algorithms have been introduced. Test hypothesis methods based on empirically estimated mean and variance of the signals delivered by the different channels have shown significant gain in terms of a tradeoff between detection sensitivity and false alarm probability. This paper discloses the concept of a new hypothesis test for temporal correlation detection methods, taking advantage of the Poisson nature of the registered counting signals, and establishes a benchmark between this test and its empirical counterpart. The simulation study validates that in the four relevant configurations of a pedestrian source carrier under respectively high and low count rate radioactive backgrounds, and a vehicle source carrier under the same respectively high and low count rate radioactive backgrounds, the newly introduced hypothesis test ensures a significantly improved compromise between sensitivity and false alarm. It also guarantees that the optimal coverage factor for this compromise remains stable regardless of signal-to-noise ratio variations between 2 and 0.8, therefore allowing the final user to parametrize the test with the sole prior knowledge of background amplitude.

  5. A robust hypothesis test for the sensitive detection of constant speed radiation moving sources

    Energy Technology Data Exchange (ETDEWEB)

    Dumazert, Jonathan, E-mail: jonathan.dumazert@cea.fr [CEA, LIST, Laboratoire Capteurs Architectures Electroniques, 91191 Gif-sur-Yvette (France); Coulon, Romain; Kondrasovs, Vladimir; Boudergui, Karim; Moline, Yoann; Sannié, Guillaume; Gameiro, Jordan; Normand, Stéphane [CEA, LIST, Laboratoire Capteurs Architectures Electroniques, 91191 Gif-sur-Yvette (France); Méchin, Laurence [CNRS, UCBN, Groupe de Recherche en Informatique, Image, Automatique et Instrumentation de Caen, 14050 Caen (France)

    2015-09-21

    Radiation Portal Monitors are deployed in linear networks to detect radiological material in motion. As a complement to single and multichannel detection algorithms, inefficient under too low signal-to-noise ratios, temporal correlation algorithms have been introduced. Test hypothesis methods based on empirically estimated mean and variance of the signals delivered by the different channels have shown significant gain in terms of a tradeoff between detection sensitivity and false alarm probability. This paper discloses the concept of a new hypothesis test for temporal correlation detection methods, taking advantage of the Poisson nature of the registered counting signals, and establishes a benchmark between this test and its empirical counterpart. The simulation study validates that in the four relevant configurations of a pedestrian source carrier under respectively high and low count rate radioactive backgrounds, and a vehicle source carrier under the same respectively high and low count rate radioactive backgrounds, the newly introduced hypothesis test ensures a significantly improved compromise between sensitivity and false alarm. It also guarantees that the optimal coverage factor for this compromise remains stable regardless of signal-to-noise ratio variations between 2 and 0.8, therefore allowing the final user to parametrize the test with the sole prior knowledge of background amplitude.

  6. Tailoring high-temperature radiation and the resurrection of the incandescent source

    Science.gov (United States)

    Ilic, Ognjen; Bermel, Peter; Chen, Gang; Joannopoulos, John D.; Celanovic, Ivan; Soljačić, Marin

    2016-04-01

    In solar cells, the mismatch between the Sun's emission spectrum and the cells’ absorption profile limits the efficiency of such devices, while in incandescent light bulbs, most of the energy is lost as heat. One way to avoid the waste of a large fraction of the radiation emitted from hot objects is to tailor the thermal emission spectrum according to the desired application. This strategy has been successfully applied to photonic-crystal emitters at moderate temperatures, but is exceedingly difficult for hot emitters (>1,000 K). Here, we show that a plain incandescent tungsten filament (3,000 K) surrounded by a cold-side nanophotonic interference system optimized to reflect infrared light and transmit visible light for a wide range of angles could become a light source that reaches luminous efficiencies (∼40%) surpassing existing lighting technologies, and nearing a limit for lighting applications. We experimentally demonstrate a proof-of-principle incandescent emitter with efficiency approaching that of commercial fluorescent or light-emitting diode bulbs, but with exceptional reproduction of colours and scalable power. The ability to tailor the emission spectrum of high-temperature sources may find applications in thermophotovoltaic energy conversion and lighting.

  7. Recovery from Iridium-192 flakes of a radioactive source for industrial use after a radiation incident

    International Nuclear Information System (INIS)

    The Iridium-192 (192Ir) is the most used and ideal for industrial radiography applications, especially in petrochemical plants and pipelines and provides better contrast sensitivity for thick (25.4 mm). This source has constructive sealed double encapsulation, the internal capsule containing stainless steel to radioactive material in the form of flakes and welded with TIG process. The radiological incident happened at a gas station fuel sales in circumstances in which there was a homogeneity test welds a tank, the flakes or Ir-192 fell off his ponytail and left scattered over an area of 2 m2, some fell flat areas and other land so collected in lead shielding and metal container and ground source. Full recovery of the leaflets was performed at the Division of radioactive waste management (GRRA) gaining a total of 22 flakes with no radiation risk to staff performance and installation and the conclusion was reached that the misapplicaion of TIG welding was the main cause the incident. (author)

  8. Locally Targeted Delivery of a Micron-Size Radiation Therapy Source Using Temperature-Sensitive Hydrogel

    International Nuclear Information System (INIS)

    Purpose: To propose a novel radiation therapy (RT) delivery modality: locally targeted delivery of micron-size RT sources by using temperature-sensitive hydrogel (RT-GEL) as an injectable vehicle. Methods and Materials: Hydrogel is a water-like liquid at room temperature but gels at body temperature. Two US Food and Drug Administration-approved polymers were synthesized. Indium-111 (In-111) was used as the radioactive RT-GEL source. The release characteristics of In-111 from polymerized RT-GEL were evaluated. The injectability and efficacy of RT-GEL delivery to human breast tumor were tested using animal models with control datasets of RT-saline injection. As proof-of-concept studies, a total of 6 nude mice were tested by injecting 4 million tumor cells into their upper backs after a week of acclimatization. Three mice were injected with RT-GEL and 3 with RT-saline. Single-photon emission computed tomography (SPECT) and CT scans were performed on each mouse at 0, 24, and 48 h after injection. The efficacy of RT-GEL was determined by comparison with that of the control datasets by measuring kidney In-111 accumulation (mean nCi/cc), representing the distant diffusion of In-111. Results: RT-GEL was successfully injected into the tumor by using a 30-gauge needle. No difficulties due to polymerization of hydrogel during injection and intratumoral pressure were observed during RT-GEL injection. No back flow occurred for either RT-GEL or RT-saline. The residual tumor activities of In-111 were 49% at 24 h (44% at 48 h, respectively) for RT-GEL and 29% (22%, respectively) for RT-saline. Fused SPECT-CT images of RT-saline showed considerable kidney accumulation of In-111 (2886%, 261%, and 262% of RT-GEL at 0, 24, and 48 h, respectively). Conclusions: RT-GEL was successfully injected and showed much higher residual tumor activity: 170% (200%, respectively), than that of RT-saline at 24 h (48 h, respectively) after injection with a minimal accumulation of In-111 to the

  9. Prediction of acoustic fields radiated into a damped cavity by an N-port source through ducts

    Science.gov (United States)

    Boudoy, M.; Martin, V.

    2003-07-01

    The use of two parameters—source impedance and source strength—to model a fluid machine radiating fluid-borne sound via ducts has led to excellent predictions when the source, a ventilator, propagates in one or two plane-wave ducts. Can such previously published methods successfully be applied to the case of a multi-port source radiating via ducts into a damped cavity? The case under study here is a car ventilation/heating unit and the aim was to predict the pressure spectrum inside the passenger compartment caused by the noise propagated through the ventilation ducts. The progressive validation procedure used indicated how and why as the system increases in complexity, predictive accuracy diminishes. The final results are nevertheless convincing and the hypotheses, which can be further refined to reflect the reality better and provide higher quality results, are clearly defined.

  10. Carbonaceous aerosols and pollutants over Delhi urban environment: Temporal evolution, source apportionment and radiative forcing

    Energy Technology Data Exchange (ETDEWEB)

    Bisht, D.S. [Indian Institute of Tropical Meteorology, New Delhi (India); Dumka, U.C., E-mail: dumka@aries.res.in [Aryabhatta Research Institute of Observational Sciences, Nainital (India); Kaskaoutis, D.G. [School of Natural Sciences, Shiv Nadar University, Tehsil Dadri (India); Pipal, A.S. [Department of Chemistry, Savitribai Phule Pune University, Pune (India); Srivastava, A.K. [Indian Institute of Tropical Meteorology, New Delhi (India); Soni, V.K.; Attri, S.D.; Sateesh, M. [India Meteorology Department, Lodhi Road, New Delhi (India); Tiwari, S. [Indian Institute of Tropical Meteorology, New Delhi (India)

    2015-07-15

    Particulate matter (PM{sub 2.5}) samples were collected over Delhi, India during January to December 2012 and analysed for carbonaceous aerosols and inorganic ions (SO{sub 4}{sup 2−} and NO{sub 3}{sup −}) in order to examine variations in atmospheric chemistry, combustion sources and influence of long-range transport. The PM{sub 2.5} samples are measured (offline) via medium volume air samplers and analysed gravimetrically for carbonaceous (organic carbon, OC; elemental carbon, EC) aerosols and inorganic ions (SO{sub 4}{sup 2−} and NO{sub 3}{sup −}). Furthermore, continuous (online) measurements of PM{sub 2.5} (via Beta-attenuation analyser), black carbon (BC) mass concentration (via Magee scientific Aethalometer) and carbon monoxide (via CO-analyser) are carried out. PM{sub 2.5} (online) range from 18.2 to 500.6 μg m{sup −3} (annual mean of 124.6 ± 87.9 μg m{sup −3}) exhibiting higher night-time (129.4 μg m{sup −3}) than daytime (103.8 μg m{sup −3}) concentrations. The online concentrations are 38% and 28% lower than the offline during night and day, respectively. In general, larger night-time concentrations are found for the BC, OC, NO{sub 3}{sup −}and SO{sub 4}{sup 2−}, which are seasonally dependent with larger differences during late post-monsoon and winter. The high correlation (R{sup 2} = 0.74) between OC and EC along with the OC/EC of 7.09 (day time) and 4.55 (night-time), suggest significant influence of biomass-burning emissions (burning of wood and agricultural waste) as well as secondary organic aerosol formation during daytime. Concentrated weighted trajectory (CWT) analysis reveals that the potential sources for the carbonaceous aerosols and pollutants are local emissions within the urban environment and transported smoke from agricultural burning in northwest India during post-monsoon. BC radiative forcing estimates result in very high atmospheric heating rates (~ 1.8–2.0 K day{sup −1}) due to agricultural burning effects

  11. Carbonaceous aerosols and pollutants over Delhi urban environment: Temporal evolution, source apportionment and radiative forcing

    International Nuclear Information System (INIS)

    Particulate matter (PM2.5) samples were collected over Delhi, India during January to December 2012 and analysed for carbonaceous aerosols and inorganic ions (SO42− and NO3−) in order to examine variations in atmospheric chemistry, combustion sources and influence of long-range transport. The PM2.5 samples are measured (offline) via medium volume air samplers and analysed gravimetrically for carbonaceous (organic carbon, OC; elemental carbon, EC) aerosols and inorganic ions (SO42− and NO3−). Furthermore, continuous (online) measurements of PM2.5 (via Beta-attenuation analyser), black carbon (BC) mass concentration (via Magee scientific Aethalometer) and carbon monoxide (via CO-analyser) are carried out. PM2.5 (online) range from 18.2 to 500.6 μg m−3 (annual mean of 124.6 ± 87.9 μg m−3) exhibiting higher night-time (129.4 μg m−3) than daytime (103.8 μg m−3) concentrations. The online concentrations are 38% and 28% lower than the offline during night and day, respectively. In general, larger night-time concentrations are found for the BC, OC, NO3−and SO42−, which are seasonally dependent with larger differences during late post-monsoon and winter. The high correlation (R2 = 0.74) between OC and EC along with the OC/EC of 7.09 (day time) and 4.55 (night-time), suggest significant influence of biomass-burning emissions (burning of wood and agricultural waste) as well as secondary organic aerosol formation during daytime. Concentrated weighted trajectory (CWT) analysis reveals that the potential sources for the carbonaceous aerosols and pollutants are local emissions within the urban environment and transported smoke from agricultural burning in northwest India during post-monsoon. BC radiative forcing estimates result in very high atmospheric heating rates (~ 1.8–2.0 K day−1) due to agricultural burning effects during the 2012 post-monsoon season. - Highlights: • Very high PM2.5 (> 200 µg m−3) levels over Delhi during agricultural

  12. Quantifying sources, transport, deposition, and radiative forcing of black carbon over the Himalayas and Tibetan Plateau

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rudong; Wang, Hailong; Qian, Yun; Rasch, Philip J.; Easter, Richard C.; Ma, Po-Lun; Singh, Balwinder; Huang, Jianping; Fu, Qiang

    2015-01-01

    Black carbon (BC)particles over the Himalayas and Tibetan Plateau (HTP), both airborne and those deposited on snow, have been shown to affect snowmelt and glacier retreat. Since BC over the HTP may originate from a variety of geographical regions and emission sectors, it is essential to quantify the source-receptor relationships of BC in order to understand the contributions of natural and anthropogenic emissions and provide guidance for potential mitigation actions. In this study, we use the Community Atmosphere Model version 5 (CAM5) with a newly developed source tagging technique, nudged towards the MERRA meteorological reanalysis, to characterize the fate of BC particles emitted from various geographical regions and sectors. Evaluated against observations over the HTP and surrounding regions, the model simulation shows a good agreement in the seasonal variation of the near-surface airborne BC concentrations, providing confidence to use this modeling framework for characterizing BC source- receptor relationships. Our analysis shows that the relative contributions from different geographical regions and source sectors depend on seasons and the locations in the HTP. The largest contribution to annual mean BC burden and surface deposition in the entire HTP region is from biofuel and biomass (BB) emissions in South Asia, followed by fossil fuel (FF) emissions from South Asia, then FF from East Asia. The same roles hold for all the seasonal means except for the summer when East Asia FF becomes more important. For finer receptor regions of interest, South Asia BB and FF have the largest impact on BC in Himalayas and Central Tibetan Plateau, while East Asia FF and BB contribute the most to Northeast Plateau in all seasons and Southeast Plateau in the summer. Central Asia and Middle East FF emissions have relatively more important contributions to BC reaching Northwest Plateau, especially in the summer. Although the HTP local emissions only contribute about 10% of BC in

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

    Science.gov (United States)

    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

  14. Leaf surface wax is a source of plant methane formation under UV radiation and in the presence of oxygen

    DEFF Research Database (Denmark)

    Bruhn, Dan; Mikkelsen, Teis Nørgaard; Rolsted, M. M. M.;

    2014-01-01

    The terrestrial vegetation is a source of UV radiation-induced aerobic methane (CH4) release to the atmosphere. Hitherto pectin, a plant structural component, has been considered as the most likely precursor for this CH4 release. However, most of the leaf pectin is situated below the surface wax...... investigated the potential of the leaf surface wax itself as a source of UV radiationinduced leaf aerobic CH4 formation. Isolated leaf surface wax emitted CH4 at substantial rates in response to UV radiation. This discovery has implications for how the phenomenon should be scaled to global levels. In relation...... to this, we demonstrated that the UV radiation-induced CH4 emission is independent of leaf area index above unity. Further, we observed that the presence of O2 in the atmosphere was necessary for achieving the highest rates of CH4 emission. Methane formation from leaf surface wax is supposedly a two...

  15. Combined radiative and natural or forced convective heat transfer between parallel vertical plates with two-dimensional discrete heat sources

    Energy Technology Data Exchange (ETDEWEB)

    Nickell, T.W.

    1988-01-01

    This study numerically analyzes combined radiative and natural or forced convective heat transfer between vertical parallel plates with two-dimensional discrete heat sources. The numerical method was verified by comparing its results with other published experimental data and the agreement was excellent. It is shown that radiative heat transfer is a significant and useful mode of heat transfer in combination with both natural and forced convection in this situation and cannot be neglected. Radiative heat transfer accounted for 50-60% or more of the total heat transfer in some cases, and usually approximately 30-35% on the top of a discrete heat source. This fact can be used to advantage in the thermal design of electronic circuit boards.

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

    Science.gov (United States)

    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.

  17. Radon Adsorbed in Activated Charcoal--A Simple and Safe Radiation Source for Teaching Practical Radioactivity in Schools and Colleges

    Science.gov (United States)

    Al-Azmi, Darwish; Mustapha, Amidu O.; Karunakara, N.

    2012-01-01

    Simple procedures for teaching practical radioactivity are presented in a way that attracts students' attention and does not make them apprehensive about their safety. The radiation source is derived from the natural environment. It is based on the radioactivity of radon, a ubiquitous inert gas, and the adsorptive property of activated charcoal.…

  18. Advisory Committee on human radiation experiments. Final report, Supplemental Volume 2. Sources and documentation

    International Nuclear Information System (INIS)

    This volume and its appendixes supplement the Advisory Committee's final report by reporting how we went about looking for information concerning human radiation experiments and intentional releases, a description of what we found and where we found it, and a finding aid for the information that we collected. This volume begins with an overview of federal records, including general descriptions of the types of records that have been useful and how the federal government handles these records. This is followed by an agency-by-agency account of the discovery process and descriptions of the records reviewed, together with instructions on how to obtain further information from those agencies. There is also a description of other sources of information that have been important, including institutional records, print resources, and nonprint media and interviews. The third part contains brief accounts of ACHRE's two major contemporary survey projects (these are described in greater detail in the final report and another supplemental volume) and other research activities. The final section describes how the ACHRE information-nation collections were managed and the records that ACHRE created in the course of its work; this constitutes a general finding aid for the materials deposited with the National Archives. The appendices provide brief references to federal records reviewed, descriptions of the accessions that comprise the ACHRE Research Document Collection, and descriptions of the documents selected for individual treatment. Also included are an account of the documentation available for ACHRE meetings, brief abstracts of the almost 4,000 experiments individually described by ACHRE staff, a full bibliography of secondary sources used, and other information

  19. Detection of embedded radiation sources using temporal variation of gamma spectral data.

    Energy Technology Data Exchange (ETDEWEB)

    Shokair, Isaac R.

    2011-09-01

    Conventional full spectrum gamma spectroscopic analysis has the objective of quantitative identification of all the isotopes present in a measurement. For low energy resolution detectors, when photopeaks alone are not sufficient for complete isotopic identification, such analysis requires template spectra for all the isotopes present in the measurement. When many isotopes are present it is difficult to make the correct identification and this process often requires many trial solutions by highly skilled spectroscopists. This report investigates the potential of a new analysis method which uses spatial/temporal information from multiple low energy resolution measurements to test the hypothesis of the presence of a target spectrum of interest in these measurements without the need to identify all the other isotopes present. This method is referred to as targeted principal component analysis (TPCA). For radiation portal monitor applications, multiple measurements of gamma spectra are taken at equally spaced time increments as a vehicle passes through the portal and the TPCA method is directly applicable to this type of measurement. In this report we describe the method and investigate its application to the problem of detection of a radioactive localized source that is embedded in a distributed source in the presence of an ambient background. Examples using simulated spectral measurements indicate that this method works very well and has the potential for automated analysis for RPM applications. This method is also expected to work well for isotopic detection in the presence of spectrally and spatially varying backgrounds as a result of vehicle-induced background suppression. Further work is needed to include effects of shielding, to understand detection limits, setting of thresholds, and to estimate false positive probability.

  20. Advisory Committee on human radiation experiments. Final report, Supplemental Volume 2. Sources and documentation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    This volume and its appendixes supplement the Advisory Committee`s final report by reporting how we went about looking for information concerning human radiation experiments and intentional releases, a description of what we found and where we found it, and a finding aid for the information that we collected. This volume begins with an overview of federal records, including general descriptions of the types of records that have been useful and how the federal government handles these records. This is followed by an agency-by-agency account of the discovery process and descriptions of the records reviewed, together with instructions on how to obtain further information from those agencies. There is also a description of other sources of information that have been important, including institutional records, print resources, and nonprint media and interviews. The third part contains brief accounts of ACHRE`s two major contemporary survey projects (these are described in greater detail in the final report and another supplemental volume) and other research activities. The final section describes how the ACHRE information-nation collections were managed and the records that ACHRE created in the course of its work; this constitutes a general finding aid for the materials deposited with the National Archives. The appendices provide brief references to federal records reviewed, descriptions of the accessions that comprise the ACHRE Research Document Collection, and descriptions of the documents selected for individual treatment. Also included are an account of the documentation available for ACHRE meetings, brief abstracts of the almost 4,000 experiments individually described by ACHRE staff, a full bibliography of secondary sources used, and other information.

  1. Effects of Ionizing Radiations on the Haematopoietic Tissue. Proceedings of a Panel on the Effects of Various Types of Ionizing Radiations from Different Sources on Haematopoietic Tissue

    International Nuclear Information System (INIS)

    The atomic energy industry and the medical sciences are making increasing use of gamma and X-irradiation as well as neutron, proton and mixed irradiation of high-energy particles from reactors, both in research work and in the treatment of patients. For this reason the need for a more detailed investigation of the influence of different sources of irradiation on the haematopoietic tissue becomes more urgent from day to day. This task should no longer be considered as a purely scientific one, but rather as a matter of practical application, since an understanding of the radiosensitivity of haematopoietic tissue is essential in treating patients by X-ray or other radioactive therapies, as well as in treating persons involved in radiation accidents, particularly where bone-marrow or organ transplantation is necessary. A panel of experts on ''The Effects of Various Types of Ionizing Radiations from Different Sources on Haematopoietic Tissue'' was convened by the International Atomic Energy Agency at its headquarters in Vienna from 17 to 20 May, 1966. The meeting was attended by 22 experts from 13 countries. The object was to discuss (1) the facts and concepts of normal haematopoiesis and its regulation, (2) the qualitative and quantitative aspects of the effects of conventional radiation sources on haematopoiesis, and (3) the comparative reactions of haematopoietic tissue from different animals after irradiation. The meeting produced a stimulating exchange of ideas, as is witnessed by this publication, which contains all the papers and discussions

  2. Studies of longitudinal profile of electron bunches and impedance measurements at Indus-2 synchrotron radiation source

    Science.gov (United States)

    Garg, Akash Deep; Yadav, S.; Kumar, Mukesh; Shrivastava, B. B.; Karnewar, A. K.; Ojha, A.; Puntambekar, T. A.

    2016-04-01

    Indus-2 is a 3rd generation synchrotron radiation source at the Raja Ramanna Centre for Advanced Technology (RRCAT) in India. We study the longitudinal profile of electrons in Indus-2 by using dual sweep synchroscan streak camera at visible diagnostic beamline. In this paper, the longitudinal profiles of electron bunch are analyzed by filling beam current in a single bunch mode. These studies are carried at injection energy (550 MeV) and at ramped beam energy (2.5 GeV). The effects of the wakefield generated interactions between the circulating electrons and the surrounding vacuum chamber are analyzed in terms of measured effects on longitudinal beam distribution. The impedance of the storage ring is obtained by fitting the solutions of Haissinski equation to the measured bunch lengthening with different impedance models. The impedance of storage ring obtained by a series R+L impedance model indicates a resistance (R) of 1350±125 Ω, an inductance (L) of 180±25 nH and broadband impedance of 2.69 Ω. These results are also compared with the values obtained from measured synchronous phase advancing and scaling laws. These studies are very useful in better understanding and control of the electromagnetic interactions.

  3. An isotopic analysis of ionising radiation as a source of sulphuric acid

    Directory of Open Access Journals (Sweden)

    M. B. Enghoff

    2012-06-01

    Full Text Available Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions enhance the formation of sulphuric acid aerosols, but the exact mechanism has remained undetermined. Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a missing source. In this study the production of sulphuric acid from SO2 through a number of different pathways is investigated. The production methods are standard gas phase oxidation by OH radicals produced by ozone photolysis with UV light, liquid phase oxidation by ozone, and gas phase oxidation initiated by gamma rays. The distributions of stable sulphur isotopes in the products and substrate were measured using isotope ratio mass spectrometry. All methods produced sulphate enriched in 34S and we find an enrichment factor (δ34S of 8.7 ± 0.4‰ (1 standard deviation for the UV-initiated OH reaction. Only UV light (Hg emission at 253.65 nm produced a clear non-mass-dependent excess of 33S. The pattern of isotopic enrichment produced by gamma rays is similar, but not equal, to that produced by aqueous oxidation of SO2 by ozone. This, combined with the relative yields of the experiments, suggests a mechanism in which ionising radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV to S(VI conversion.

  4. An isotope view on ionising radiation as a source of sulphuric acid

    Directory of Open Access Journals (Sweden)

    M. B. Enghoff

    2012-02-01

    Full Text Available Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions enhance the formation of sulphuric acid aerosols, but the exact mechanism has remained undetermined. Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a missing source. In this study the production of sulphuric acid from SO2 through a number of different pathways is investigated. The production methods are standard gas phase oxidation by OH radicals produced by ozone photolysis with UV light, liquid phase oxidation by ozone, and gas phase oxidation initiated by gamma rays. The distributions of stable sulphur isotopes in the products and substrate were measured using isotope ratio mass spectrometry. All methods produced sulphate enriched in 34S and we find a δ34S value of 8.7 ± 0.4‰ (1 standard deviation for the UV-initiated OH reaction. Only UV light (Hg emission at 253.65 nm produced a clear non-mass-dependent excess of 33S. The pattern of isotopic enrichment produced by gamma rays is similar, but not equal, to that produced by aqueous oxidation of SO2 by ozone. This, combined with the relative yields of the experiments, suggests a mechanism in which ionising radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV to S(VI conversion.

  5. The electron-cyclotron maser instability as a source of plasma radiation. [Solar radio bursts

    Science.gov (United States)

    Winglee, R. M.; Dulk, G. A.

    1986-01-01

    The generation of continuum bursts from the sun at dm and m wavelengths (in particular, type IV bursts) via the electron-cyclotron-maser instability is examined. The maser instability can be driven by an electron distribution with either a loss-cone anisotropy or a peak at large pitch angles. For omega(p)/Omega(e) much greater than 1, the maser emission is produced by electrons interacting through a harmonic (cyclotron) resonance and is electrostatic, being in the upper hybrid mode at frequencies approximately equal to omega(p). Coalescence processes are required to convert the electrostatic waves into transverse radiation which can escape from the source region. Whether the resultant spectrum is nearly a smooth continuum or has a zebra-stripe pattern (both of which occur in type IV bursts) depends on the form of the electron distribution, inhomogeneities in the density and magnetic field, and whether the maser reaches saturation. For at least the case of some type IV dm bursts with fine structure, comparison with observations seems to indicate that the electrons producing the emission are more likely to have a loss-cone distribution, and that the maser instability is not at saturation.

  6. Declaration and authorization forms for the fabrication, distribution or use of radioactive sources or electric generators of ionizing radiation

    International Nuclear Information System (INIS)

    This document gathers all the forms to be completed when declaring or when asking for an authorization for the fabrication, retailing or use of radioactive sources or electric equipment generating ionizing radiation. These forms can concern all domains (use of sealed radioactive sources, possession and use of a particle accelerator or of radionuclides, import or export of radionuclides or of products containing radionuclides), or the use of such materials or equipment in the medical sector, or the fabrication and use in industry or research, or in user's guides for radioactive sources

  7. Investigation of gamma-ray fingerprint identifying mechanism for the types of radiation sources

    CERN Document Server

    Liu Su Ping; Gu Dang Chang; Gong-Jian; Hao Fan Hua; Hu Guang Chun

    2002-01-01

    Radiation fingerprints sometimes can be used to label and identify the radiation resources. For instance, in a future nuclear reduction treaty that requires verification of irreversible dismantling of reduced nuclear warheads, the radiation fingerprints of nuclear warheads are expected to play a key role in labelling and identifying the reduced warheads. It would promote the development of nuclear warheads deep-cuts verification technologies if authors start right now some investigations on the issues related to the radiation fingerprints. The author dedicated to the investigation of gamma-ray fingerprint identifying mechanism for the types of radiation resources. The purpose of the identifying mechanism investigation is to find a credible way to tell whether any two gamma-ray spectral fingerprints that are under comparison are radiated from the same resource. The authors created the spectrum pattern comparison (SPC) to study the comparability of the two radiation fingerprints. Guided by the principle of SPC,...

  8. Study of the source term of radiation of the CDTN GE-PET trace 8 cyclotron with the MCNPX code

    Energy Technology Data Exchange (ETDEWEB)

    Benavente C, J. A.; Lacerda, M. A. S.; Fonseca, T. C. F.; Da Silva, T. A. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil); Vega C, H. R., E-mail: jhonnybenavente@gmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2015-10-15

    Full text: The knowledge of the neutron spectra in a PET cyclotron is important for the optimization of radiation protection of the workers and individuals of the public. The main objective of this work is to study the source term of radiation of the GE-PET trace 8 cyclotron of the Development Center of Nuclear Technology (CDTN/CNEN) using computer simulation by the Monte Carlo method. The MCNPX version 2.7 code was used to calculate the flux of neutrons produced from the interaction of the primary proton beam with the target body and other cyclotron components, during 18F production. The estimate of the source term and the corresponding radiation field was performed from the bombardment of a H{sub 2}{sup 18}O target with protons of 75 μA current and 16.5 MeV of energy. The values of the simulated fluxes were compared with those reported by the accelerator manufacturer (GE Health care Company). Results showed that the fluxes estimated with the MCNPX codes were about 70% lower than the reported by the manufacturer. The mean energies of the neutrons were also different of that reported by GE Health Care. It is recommended to investigate other cross sections data and the use of physical models of the code itself for a complete characterization of the source term of radiation. (Author)

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

    Science.gov (United States)

    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 (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.

  10. Study of the source term of radiation of the CDTN GE-PET trace 8 cyclotron with the MCNPX code

    International Nuclear Information System (INIS)

    Full text: The knowledge of the neutron spectra in a PET cyclotron is important for the optimization of radiation protection of the workers and individuals of the public. The main objective of this work is to study the source term of radiation of the GE-PET trace 8 cyclotron of the Development Center of Nuclear Technology (CDTN/CNEN) using computer simulation by the Monte Carlo method. The MCNPX version 2.7 code was used to calculate the flux of neutrons produced from the interaction of the primary proton beam with the target body and other cyclotron components, during 18F production. The estimate of the source term and the corresponding radiation field was performed from the bombardment of a H218O target with protons of 75 μA current and 16.5 MeV of energy. The values of the simulated fluxes were compared with those reported by the accelerator manufacturer (GE Health care Company). Results showed that the fluxes estimated with the MCNPX codes were about 70% lower than the reported by the manufacturer. The mean energies of the neutrons were also different of that reported by GE Health Care. It is recommended to investigate other cross sections data and the use of physical models of the code itself for a complete characterization of the source term of radiation. (Author)

  11. Radiation Protection of Patients, Staff and the Public During Therapeutic Use of Sealed and Unsealed Radioactive Sources: Introductory Remarks

    International Nuclear Information System (INIS)

    For decades, radioactive substances have been used for beneficial medical treatments. Nowadays, radiotherapy is a dynamic medical area. In recent years, there has been rapid technological development of hardware and software, new procedures, new treatment protocols and novel application of radionuclides. This requires a qualified control of medical radiation exposure. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) estimated that in 2007 the global use of radiotherapy increased to 5.1 million treatment courses per year, with a rising tendency. The major challenges of radiation protection for new techniques and new procedures in radiotherapy are their complexity and the high radioactivity of the applied sealed or unsealed sources. Radioactive sources — unsealed or sealed — are characterized by their type of radiation, the particle energy, the chemical composition, and their format and size. In addition, such sources cannot be switched off easily as can be done with X ray machines and accelerators. Thus, there is a high potential for the occurrence of accidents with serious consequences with such applications. In recent years, there have been reports of accidents in which there were unnecessary exposures to a large number of patients. Improving patient dosimetry and avoiding unnecessary exposures, particularly in unusual and novel applications, are important goals in medical radiation protection, in particular as international recommendations and basic safety standards in radiation protection do not suggest and implement any exposure limits for medical exposure. Appropriate control of the correct functioning of devices (hardware and software) as well as of the dose delivered to the patient is necessary

  12. High power THz source based on coherent radiation of picosecond relativistic electron bunch train

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Tunable and compact high power terahertz (THz) radiation based on coherent radiation (CR) of the picosecond relativistic electron bunch train is under development at the Tsinghua accelerator lab. Coherent synchronization radiation (CSR) and coherent transition radiation (CTR) are researched based on an S-band compact electron linac, a bending magnet or a thin foil. The bunch train’s form factors, which are the key factor of THz radiation, are analyzed by the PARMELA simulation. The effects of electron bunch trains under different conditions, such as the bunch number, bunch charges, micro-pulses inter-distance, and accelerating gradient of the gun are investigated separately in this paper. The optimal radiated THz power and spectra should take these factors as a whole into account.

  13. Change in the radiation dose at a point where an inhomogeneity partly covers the radiation field from a 60Co-γ-source

    International Nuclear Information System (INIS)

    Measurements and calculations have been made in order to study the change of the radiation dose in a point when an inhomogeneity covers parts of the radiation field from a Co 60-source. An ionization chamber, placed in a water phantom, was used for the measurements. As inhomogeneity an air cavity was used. The measuring point was placed on the central axis of the radiation field during the measurement. The air cavity was moved in front of the measuring point 0.5 - 1 cm by steps laterally, i.e. along a line perpendicular to the radiation direction. Measurements were made at different depths behind the air cavity. The air cavity was placed at different distances from the front plate of the water phantom. Measurements and calculations show that the change of the radiation dose, when the edge of the air cavity passes the measuring point, varies with the depth distance to the air cavity. The greatest deviation is near the air cavity and at a great distance behind this. The change of the radiation dose is less than 2 percent at distances greater than 2 cm from the edge of the air cavity laterally. This change is independent of the depth distance to the air cavity. The maximum deviation 1 cm from the edge of the air cavity is 5 percent independent of the distance tothe air cavity. Used methods of calculation can be extended to be used for irregular inhomogeneities but this requires knowledge of the three-dimensional extension of the inhomogeneity. (M.S.)

  14. Study of external exposure doses received by Cuban population due to terrestrial component of the environmental radiation sources

    International Nuclear Information System (INIS)

    The work presents the results of the study carried out to evaluate the doses that the Cuban population receives for the external exposition to the terrestrial component of the environmental sources of radiation. Starting from the carried out measurements it was possible to estimate the doses effective representative annual stockings that the Cuban population receives for external exposition to the terrestrial radiation, considering the permanency in indoors and outdoors. The dose received due to this component was 180±14 mSv/year. These values are in the range of those reported internationally. (author)

  15. Linear accelerator-based stereotactic radiosurgery in 140 brain metastases from malignant melanoma

    OpenAIRE

    Hauswald, Henrik; Stenke, Alina; Debus, Jürgen; Combs, Stephanie E

    2015-01-01

    Background: To retrospectively access outcome and prognostic parameters of linear accelerator-based stereotactic radiosurgery in brain metastases from malignant melanoma. Methods: Between 1990 and 2011 140 brain metastases in 84 patients with malignant melanoma (median age 56 years) were treated with stereotactic radiosurgery. At initial stereotactic radiosurgery 48 % of patients showed extracerebral control. The median count of brain metastases in a single patient was 1, the median diamete...

  16. Image-guided linear accelerator-based spinal radiosurgery for hemangioblastoma

    OpenAIRE

    Selch, Michael T.; Tenn, Steve; Agazaryan, Nzhde; Lee, Steve P; Gorgulho, Alessandra; De Salles, Antonio A. F.

    2012-01-01

    Purpose: To retrospectively review the efficacy and safety of image-guided linear accelerator-based radiosurgery for spinal hemangioblastomas. Methods: Between August 2004 and September 2010, nine patients with 20 hemangioblastomas underwent spinal radiosurgery. Five patients had von Hipple–Lindau disease. Four patients had multiple tumors. Ten tumors were located in the thoracic spine, eight in the cervical spine, and two in the lumbar spine. Tumor volume varied from 0.08 to 14.4 cc (median ...

  17. Evaluation of shelf life of tomatoes after using radiation with cobalt-60 source

    Energy Technology Data Exchange (ETDEWEB)

    Vicalvi, Maria Claudia V.; Solidonio, Evelyne G.; Melo, Patryk; Silva, Marcio Albuquerque da; Junior, Carlos Eduardo de O.C.; Silva, Glezia Renata da; Sena, Kesia Xisto F.R. de; Colaco, Waldeciro, E-mail: claudiavicalvi@hotmail.com, E-mail: k.xisto@gmail.com, E-mail: wcolaco@ufpe.com.br [Universidade Federal de Pernanbuco (UFPE), Pernambuco, PE (Brazil)

    2013-07-01

    Tomato is one of the most consumed fruits in the world and also one of the agricultural products with most losses due to its high perishability. The objective of this research was to evaluate the increased length of shelf life of tomatoes sold in the CEASA-PE through the use of radiation in doses of 1, 1.5 and 2 kGy with Cobalt-60 source. The study used three lots of 100 tomatoes each. Of which, 25 of them were used as the control group and 75 were irradiated with one of 3 different doses. The evaluation of the shelf life of tomatoes before and after use of the radiation was made from the observation of the visual aspects of the initiation of the fruit sto decay. The samples were analyzed at of every seven days. The fruit treated as the control group of the first batch were viable with no signs of decay for more than one month wrapped in sterile plastic wrap and stored at environment temperature ± 25 deg C. It was observed that at the dose of 1.0 kGy there was a delay in the induction of shelf life over 14 days. When used a dose of 1.5 kGy there was an increase of 30 days on shelf life compared with the control group. At a dose of 2.0 kGy, the tomatoes have a shelf life of 92 days. In the second batch of fruits, the duration of tomatoes of the control group was 40 days. At a dose of 1.0 kGy was an increase of 15 days compared to control fruits. When applying the dose of 1.5 kGy, the lifetime of the fruit was 70 days and at the dose of 2.0 kGy fruits were of 106 days starting from the initial date of experiment. The third and final batch,the lifetime of the fruits were not higher than those found in previous batches, the control group had a permanence of 14 days. At the dose of 1.0 kGy, there was the additional 10 days compared to the control group. At a dose of 1.5 kGy was observed that the fruits lasted 35 days starting from the initial day of the experiment and the tomatoes that were irradiated at 2.0 kGy the duration was 45 days from the start date of the

  18. Unexpected Up/Down asymmetry measured in axial radiation exiting high-temperature dynamic-hohlraum x-ray source

    Science.gov (United States)

    Sanford, T. W. L.; Lemke, R. W.; Mock, R. C.; Oliver, B. V.; Chandler, G. A.; Leeper, R. J.; Mehlhorn, T. A.; Nash, T. J.; Ruiz, C. L.; Waisman, E. M.; Peterson, D. L.; Chrien, R. E.; Idzorek, G. C.; Watt, R. G.; Roderick, N. F.; Haines, M. G.

    2002-11-01

    A 10 TW radiation source has been developed on the 20-MA Z facility that produces a high-temperature ( 215 eV) x-ray pulse. The pulse is generated in the positive z-direction through a REH (radiation exit hole), primarily from the interior of a collapsing dynamic-hohlraum (DH) centered within a z-pinch [1]. By adding an identical REH at the bottom of the hohlraum, radiation generated in the negative z direction through the bottom offers the possibility of doubling the utility of the hohlraum. Because of the up/down symmetry of the DH about the mid-plane of the z-axis (aside from the power feed), a radiation pulse similar to that exiting the top-REH (anode) is expected leaving the bottom-REH (cathode). Measurements indicate, however, that the peak radiated power exiting the top-REH is 2±0.2 times that exiting the bottom-REH. In contrast, the total energy radiated from either REH is about the same. Detailed measurements of this unexpected asymmetry, apparently dependent on polarity, together with potential origins of the asymmetry are discussed. [1] T. W. L. Sanford, et al, in press, Phys. Plasmas 9, (Aug. 2002). *Sandia is a multi-program laboratory operated by the Sandia Corporation, a Lockheed Martin Company, for the U.S. DOE under Contract No. DE-AC04-94AL85000.

  19. The source of THz radiation based on dielectric waveguide excited by sequence of electron bunches

    Science.gov (United States)

    Altmark, A. M.; Kanareykin, A. D.

    2016-07-01

    We present a new method for excitation of THz Cherenkov radiation in a dielectric waveguide by relativistic electron bunches. A sequence of bunches generates monochromatic radiation. The frequency of radiation is defined by the distance between the bunches. The studies were carried by using the newly updated BBU-3000 code which permits taking into account a number of additional options: an external quadrupole focusing system, group velocity of the wakefield, and the dielectric material loss factor. In this paper, we present our algorithm for optimizing the number and sequential positions of bunches for generation of narrow band high power THz radiation.

  20. Synchrotron Radiation Light Source and its Technical Development%同步辐射光源及其特点

    Institute of Scientific and Technical Information of China (English)

    毕拉力·木乎提江; 阿力甫江·扎依提

    2015-01-01

    同步辐射光源的出现,被人称为是继X光光源、激光光源之后,在科技领域中又一次革命性的事件。这种光源本身,也经过了第一代、第二代、第三代三个重要时期的发展。第四代同步辐射光源现已开始使用,显示出无可比拟的优越性。文章简要回顾了同步辐射研究的历史,较详细介绍了同步辐射光源的光源结构、研究亮点。综述了SASE自由电子激光的历史发展,基本原理,基本结构和主要物理特征。%Synchrotron radiation light source, known as the X-ray light source, laser light source, in the field of science and technology is a revolutionary events. The light source, has been through the first generation, second generation, the third generation of three important stages of developments. The fourth generation synchrotron radia⁃tion light source is now starting to use, There is nothing will be comparable to this superiority. In this paper, The history of synchrotron radiation is looked back briefly at first, then the light source structure and science highlights of synchrotron radiation light source are given in some detail. The history of SASE development, basic principle , basic structure and main physical characteristics are introduced.

  1. Optical design of an x-ray absorption spectroscopy beamline at Indus-2 synchrotron radiation source

    International Nuclear Information System (INIS)

    Details of optical design of EXAFS beamline at Indus-2 SRS, under development at CAT, Indore, have been discussed in this report. This beamline will cover the photon energy range of 5 keV to 20 keV and will use a bent crystal of Si(111) having 2d value equal to 6.2709 A. It will accept a horizontal divergence of 1.5 mrad. The heart of the beamline is the bent crystal polychromator which will disperse and focus the synchrotron beam at the experimental sample position. The transmitted radiation from the sample will be, subsequently, detected by a position sensitive detector (CCD type). The detector length is 25 mm. Assuming a suitable value for the distance between the source and the crystal, we have computed several geometrical parameters of the beamline, such as, Bragg angle, crystal length, crystal radius, crystal to sample distance, sample to detector distance, etc. for three different photon energies, namely, 5 keV, 10 keV, and 20 keV. The band passes around these photon energies are 0.3 keV, 1 keV and 2 keV respectively. It has been found that computed geometrical parameters are well within acceptable limits. An extensive ray tracing work was done using the software program SHADOW to evaluate the imaging properties of the beamline. It was established that the image spot size at the sample position improved substantially when the crystal is changed from spherical cylinder shape to elliptic cylinder shape. From the ray intensity plots, the average resolution of the crystal bender was estimated to be 1 eV per channel. Finally based on the optical layout of the beamline, a schematic mechanical layout of the beamline has been prepared. (author)

  2. DEVELOPMENT HISTORY OF NATURAL SOURCES DOSIMETRY LABORATORY AT THE RESEARCH INSTITUTE OF RADIATION HYGIENE AFTER PROFESSOR P.V. RAMZAEV: 1970–1986

    OpenAIRE

    E. P. Lisachenko; I. P. Stamat; N.A. Koroleva

    2016-01-01

    At the initial development stage of the Leningrad Research Institute of Radiation Hygiene natural sources dosimetry laboratory the experts focused at establishment of equipment and methodology. The following period of the lab activity was rather related to theoretical and experimental research which finally led to creation of a new in radiation hygiene field of work on standard protection of population irradiation caused by natural sources of ionizing radiation. The article describes the main...

  3. Peculiarities of the clinical course of radiation sickness and organizational decisions for radiation accidents with beta-gamma sources

    International Nuclear Information System (INIS)

    The analysis of a number of recent large scale accidents involving beta-gamma sources in the last 40 years, such as those of the Marshall Islands (1954); Windscale, UK (1957); Chernobyl, USSR (1986) and Goiania, Brazil (1987) demonstrates the predominance and importance of health and social impacts. (author)

  4. Radiation Shielding Information Center: a source of computer codes and data for fusion neutronics studies

    International Nuclear Information System (INIS)

    The Radiation Shielding Information Center (RSIC), established in 1962 to collect, package, analyze, and disseminate information, computer codes, and data in the area of radiation transport related to fission, is now being utilized to support fusion neutronics technology. The major activities include: (1) answering technical inquiries on radiation transport problems, (2) collecting, packaging, testing, and disseminating computing technology and data libraries, and (3) reviewing literature and operating a computer-based information retrieval system containing material pertinent to radiation transport analysis. The computer codes emphasize methods for solving the Boltzmann equation such as the discrete ordinates and Monte Carlo techniques, both of which are widely used in fusion neutronics. The data packages include multigroup coupled neutron-gamma-ray cross sections and kerma coefficients, other nuclear data, and radiation transport benchmark problem results

  5. Shielding design of a treatment room for an accelerator-based epithermal neutron irradiation facility for BNCT

    International Nuclear Information System (INIS)

    Protecting the facility personnel and the general public from radiation exposure is a primary safety concern of an accelerator-based epithermal neutron irradiation facility. This work makes an attempt at answering the questions open-quotes How much?close quotes and open-quotes What kind?close quotes of shielding will meet the occupational limits of such a facility. Shielding effectiveness is compared for ordinary and barytes concretes in combination with and without borated polyethylene. A calculational model was developed of a treatment room, patient open-quotes scatterer,close quotes and the epithermal neutron beam. The Monte Carlo code, MCNP, was used to compute the total effective dose equivalent rates at specific points of interest outside of the treatment room. A conservative occupational effective dose rate limit of 0.01 mSv h-1 was the guideline for this study. Conservative Monte Carlo calculations show that constructing the treatment room walls with 1.5 m of ordinary concrete, 1.2 m of barytes concrete, 1.0 m of ordinary concrete preceded by 10 cm of 5% boron-polyethylene, or 0.8 m of barytes concrete preceded by 10 cm of 5% boron-polyethylene will adequately protect facility personnel. 20 refs., 8 figs., 2 tabs

  6. Radiation

    International Nuclear Information System (INIS)

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  7. Buoyancy-Driven Radiative Unsteady Magnetohydrodynamic Heat Transfer over a Stretching Sheet with non-Uniform Heat Source/sink

    Directory of Open Access Journals (Sweden)

    Dulal Pal

    2016-01-01

    Full Text Available In the present study an unsteady mixed convection boundary layer flow of an electrically conduct- ing fluid over an stretching permeable sheet in the presence of transverse magnetic field, thermal radiation and non-uniform heat source/sink effects is investigated. The unsteadiness in the flow and temperature fields is due to the time-dependent nature of the stretching velocity and the surface temperature. Both opposing and assisting flows are considered. The dimensionless governing or- dinary non-linear differential equations are solved numerically by applying shooting method using Runge-Kutta-Fehlberg method. The effects of unsteadiness parameter, buoyancy parameter, thermal radiation, Eckert number, Prandtl number and non-uniform heat source/sink parameter on the flow and heat transfer characteristics are thoroughly examined. Comparisons of the present results with previously published results for the steady case are found to be excellent.

  8. Spatiotemporal characteristics of the energy radiation sources of the three great earthquakes near Sumatra Island in September 2007

    Institute of Scientific and Technical Information of China (English)

    XU LiSheng; DU HaiLin; ZHANG HongXia; ZHANG Yong; LI ChunLai; ZHAO Hua

    2008-01-01

    Three strong earthquakes with magnitudes of Mw 8.4, Mw 7.9 and Mw 7.0 occurred in the sea west of Sumatra island on September 12 and 13, 2007. We relocated the epicenters and focal depths of the three events by means of the reversal-time imaging technique using broadband digital seismic data from worldwide stations ranging from 30°to 90°, imaged the spatiotemporal variation of the energy radiation sources by means of the nonplane wave array technique using the broadband digital seismic data from a generalized array made up of 33 stations of the Capital Region Digital Seismograph Network (CRDSN), and obtained the rupture duration times, extents and rupture velocities. Also, we discussed the correlations between the locations of the energy radiation sources of the three events.

  9. Study on effect of geometrical configuration of radioactive source material to the radiation intensity of betavoltaic nuclear battery

    Energy Technology Data Exchange (ETDEWEB)

    Badrianto, Muldani Dwi; Riupassa, Robi D.; Basar, Khairul, E-mail: khbasar@fi.itb.ac.id [Nuclear Physics and Biophysics Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung (Indonesia)

    2015-09-30

    Nuclear batteries have strategic applications and very high economic potential. One Important problem in application of nuclear betavoltaic battery is its low efficiency. Current efficiency of betavoltaic nuclear battery reaches only arround 2%. One aspect that can influence the efficiency of betavoltaic nuclear battery is the geometrical configuration of radioactive source. In this study we discuss the effect of geometrical configuration of radioactive source material to the radiation intensity in betavoltaic nuclear battery system. received by the detector. By obtaining the optimum configurations, the optimum usage of radioactive materials can be determined. Various geometrical configurations of radioactive source material are simulated. It is obtained that usage of radioactive source will be optimum for circular configuration.

  10. A Note on the Analysis of Electrodynamic Fields Radiated by Time-Harmonic Sources Within Non-Birefringent Anisotropic Media

    CERN Document Server

    Sainath, Kamalesh

    2015-01-01

    We address a challenge concerning the spectral-domain-based analysis of electromagnetic fields produced by time-harmonic current sources within planar-layered media, which arises specifically when sources are embedded inside non-birefringent anisotropic medium (NBAM) layers. In NBAM, the highly symmetric permeability and permittivity tensors can induce directionally-dependent, but polarization independent, propagation properties supporting "degenerate" characteristic polarizations. That is to say, the considered NBAM support four linearly independent field polarization eigenvectors associated with only two (rather than four) unique, non-defective eigenvalues. We explain problems that can arise when the source(s) specifically reside within NBAM planar layers when using canonical field expressions as well as obtain alternative expressions, immune to such problems, that form the foundation for a robust eigenfunction-based analysis of electromagnetic radiation and scattering within planar-layered media.

  11. Physiologically gated micro-beam radiation therapy using electronically controlled field emission x-ray source array

    Science.gov (United States)

    Chtcheprov, Pavel; Hadsell, Michael; Burk, Laurel; Ger, Rachel; Zhang, Lei; Yuan, Hong; Lee, Yueh Z.; Chang, Sha; Lu, Jianping; Zhou, Otto

    2013-03-01

    Micro-beam radiation therapy (MRT) uses parallel planes of high dose narrow (10-100 um in width) radiation beams separated by a fraction of a millimeter to treat cancerous tumors. This experimental therapy method based on synchrotron radiation has been shown to spare normal tissue at up to 1000Gy of entrance dose while still being effective in tumor eradication and extending the lifetime of tumor-bearing small animal models. Motion during the treatment can result in significant movement of micro beam positions resulting in broader beam width and lower peak to valley dose ratio (PVDR), and thus can reduce the effectiveness of the MRT. Recently we have developed the first bench-top image guided MRT system for small animal treatment using a high powered carbon nanotube (CNT) x-ray source array. The CNT field emission x-ray source can be electronically synchronized to an external triggering signal to enable physiologically gated firing of x-ray radiation to minimize motion blurring. Here we report the results of phantom study of respiratory gated MRT. A simulation of mouse breathing was performed using a servo motor. Preliminary results show that without gating the micro beam full width at tenth maximum (FWTM) can increase by 70% and PVDR can decrease up to 50%. But with proper gating, both the beam width and PVDR changes can be negligible. Future experiments will involve irradiation of mouse models and comparing histology stains between the controls and the gated irradiation.

  12. The ascending aortic image quality and the whole aortic radiation dose of high-pitch dual-source CT angiography

    OpenAIRE

    Liu, Ying; Xu, Jian; Jian LI; Ren, Jing; LIU, HONGTAO; Xu, Junqing; Wei, Mengqi; Hao, Yuewen; Zheng, Minwen

    2013-01-01

    Background Aortic dissection is a lift-threatening medical emergency associated with high rates of morbidity and mortality. The incidence rate of aortic dissection is estimated at 5 to 30 per 1 million people per year. The prompt and correct diagnosis of aortic dissection is critical. This study was to compare the ascending aortic image quality and the whole aortic radiation dose of high-pitch dual-source CT angiography and conventional dual-source CT angiography. Methods A total of 110 conse...

  13. Applications of photon-in, photon-out spectroscopy with third-generation, synchrotron-radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Lindle, D.W.; Perera, R.C.C. (eds.)

    1991-01-01

    This report discusses the following topics: Mother nature's finest test probe; soft x-ray emission spectroscopy with high-brightness synchrotron radiation sources; anisotropy and polarization of x-ray emission from atoms and molecules; valence-hole fluorescence from molecular photoions as a probe of shape-resonance ionization: progress and prospects; structural biophysics on third-generation synchrotron sources; ultra-soft x-ray fluorescence-yield XAFS: an in situ photon-in, photon-out spectroscopy; and x-ray microprobe: an analytical tool for imaging elemental composition and microstructure.

  14. Applications of photon-in, photon-out spectroscopy with third-generation, synchrotron-radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Lindle, D.W.; Perera, R.C.C. [eds.

    1991-12-31

    This report discusses the following topics: Mother nature`s finest test probe; soft x-ray emission spectroscopy with high-brightness synchrotron radiation sources; anisotropy and polarization of x-ray emission from atoms and molecules; valence-hole fluorescence from molecular photoions as a probe of shape-resonance ionization: progress and prospects; structural biophysics on third-generation synchrotron sources; ultra-soft x-ray fluorescence-yield XAFS: an in situ photon-in, photon-out spectroscopy; and x-ray microprobe: an analytical tool for imaging elemental composition and microstructure.

  15. National regulatory authorities with competence in the safety of radiation sources and the security of radioactive materials. Proceedings

    International Nuclear Information System (INIS)

    The Buenos Aires Conference, hosted by the Government of Argentina, was attended by 89 regulatory officials from 57 Member States. The conference provided a forum for fostering the exchange of information and experience on the development of adequate regulatory systems for effective control of the safety of radiation sources and security of radioactive materials. This publication contains 64 individual presentations delivered at the Conference. Each of them was indexed separately

  16. Analytical formulae to calculate the solid angle subtended at an arbitrarily positioned point source by an elliptical radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Mahmoud I., E-mail: mabbas@physicist.net [Physics Department, Faculty of Science, Alexandria University, 21511 Alexandria (Egypt); Hammoud, Sami [Physics Department, Faculty of Science, Beirut Arab University, Beirut (Lebanon); Physics Department, Faculty of Science and Art, Lebanese International University (Lebanon); Ibrahim, Tarek; Sakr, Mohamed [Physics Department, Faculty of Science, Beirut Arab University, Beirut (Lebanon)

    2015-01-21

    In this article, we introduce a direct analytical mathematical method for calculating the solid angle, Ω, subtended at a point by closed elliptical contours. The solid angle is required in many areas of optical and nuclear physics to estimate the flux of particle beam of radiation and to determine the activity of a radioactive source. The validity of the derived analytical expressions was successfully confirmed by the comparison with some published data (Numerical Method)

  17. The pitch angle paradox and radiative life times in a synchrotron source

    CERN Document Server

    Singal, Ashok K

    2016-01-01

    In synchrotron radiation there is a paradox whether or not the pitch angle of a radiating charge varies. The conventional wisdom is that the pitch angle does not change during the radiation process. The argument is based on Larmor's radiation formula, where in a synchrotron case the radiation power is along the instantaneous direction of motion of the charge. Then the momentum loss will also be parallel to that direction and therefore the pitch angle of the charge would remain unaffected. The accordingly derived formulas for energy losses of synchrotron electrons in radio galaxies are the standard text-book material for the last 50 years. However, if we use the momentum transformation laws from special relativity, then we find that the pitch angle of a radiating charge varies. While the velocity component parallel to the magnetic field remains unaffected, the perpendicular component does reduce in magnitude due to radiative losses, implying a change in the pitch angle. This apparent paradox is resolved when e...

  18. Development of a cryogenic EOS capability for the Z Pulsed Radiation Source: Goals and accomplishments of FY97 LDRD project

    International Nuclear Information System (INIS)

    Experimental cryogenic capabilities are essential for the study of ICF high-gain target and weapons effects issues involving dynamic materials response at low temperatures. This report describes progress during the period 2/97-11/97 on the FY97 LDRD project ''Cryogenic EOS Capabilities on Pulsed Radiation Sources (Z Pinch)''. The goal of this project is the development of a general purpose cryogenic target system for precision EOS and shock physics measurements at liquid helium temperatures on the Z accelerator Z-pinch pulsed radiation source. Activity during the FY97 LDRD phase of this project has focused on development of a conceptual design for the cryogenic target system based on consideration of physics, operational, and safety issues, design and fabrication of principal system components, construction and instrumentation of a cryogenic test facility for off-line thermal and optical testing at liquid helium temperatures, initial thermal testing of a cryogenic target assembly, and the design of a cryogenic system interface to the Z pulsed radiation source facility. The authors discuss these accomplishments as well as elements of the project that require further work

  19. Compact and spatially coherent X-ray source based on cryogenic ERL. Basic design of the X-ray radiator

    International Nuclear Information System (INIS)

    The development of spatially coherent X-ray generator based on the compact energy recovery linac (ERL) has been studied in collaboration with Nihon University, High Energy Accelerator Research Organization (KEK) and Toyama. In this novel source, parametric X-ray radiation (PXR), which is a radiation phenomenon caused by the interaction between a charged particle and a crystal medium, is used for X-ray production. Thus, a thin crystal plate such as silicon or diamond irradiated with the electron beam from the ERL acts as an X-ray radiator. Since the acceptance of the deceleration tube restricts the emittance growth of the electron beam at the radiator, we define the maximum thickness of the radiator crystal as 0.2 mm. Under this condition, the properties of the available PXR beam were investigated using Monte Carlo simulations. The results show possibility of X-ray photon rate higher than 109 /s when the electron beam current is 30 μA. (author)

  20. Conceptual design of Hefei advanced light source

    Institute of Scientific and Technical Information of China (English)

    LI Wei-Min; WANG Lin; FENG Guang-Yao; ZHANG Shan-Cai; WU Cong-Feng; LIU Zu-Ping

    2009-01-01

    The conceptual of Hefei Advanced Light Source,which is an advanced VUV and Soft X-ray source,was developed at NSRL of USTC.According to the synchrotron radiation user requirements and the trends of SR source development.some accelerator-based schemes were considered and compared;furthermore storage ring With ultra low emittance Was adopted as the baseline scheme of HALS.To achieve ultra low emittance.some focusing structures were studied and optimized in the lattice design.Compromising of emittance,onmomentum and off-momentum dynamic aperture and ring scale,five bend acromat(FBA)Was employed.In the preliminary design of HALS,the emittance Was reduced to sub nm-rad,thus the radiation up to water window has full lateral coherence.The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders.The HALS should be one of the most advanced synchrotron radiation light sources in the world.

  1. Realistic assessment of direct radiolysis for synthetic fuels production using fusion radiation sources

    International Nuclear Information System (INIS)

    These studies indicate that synthetic fuel production by direct radiolysis cannot compete economically with other production methods. Low G-values and radiation contamination of products are given as reasons

  2. A Critical Experimental Test of Synchrotron Radiation Theory with 3rd Generation Light Source

    CERN Document Server

    Geloni, Gianluca; Saldin, Evgeni

    2016-01-01

    A recent "beam splitting" experiment at LCLS apparently demonstrated that after a microbunched electron beam is kicked on a large angle compared to the divergence of the FEL radiation, the microbunching wave front is readjusted along the new direction of motion of the kicked beam. Therefore, coherent radiation from an undulator placed after the kicker is emitted along the kicked direction without suppression. This strong emission of coherent undulator radiation in the kicked direction cannot be explained in the framework of conventional synchrotron radiation theory. In a previous paper we explained this puzzle. We demonstrated that, in accelerator physics, the coupling of fields and particles is based, on the one hand, on the use of results from particle dynamics treated according to the absolute time convention and, on the other hand, on the use of Maxwell equations treated according to the standard (Einstein) synchronization convention. Here lies the misconception which led to the strong qualitative disagre...

  3. SOME ASPECTS OF ORGANISING SUPERVISION OVER ARTIFICIAL SOURCES OF IONIZING RADIATION IN CHELYABINSK REGION

    Directory of Open Access Journals (Sweden)

    A. I. Semenov

    2012-01-01

    Full Text Available In experiments on rats (290 animals exposed to chronic gamma-radiation in the total dose of 10.0 Gy it was detected that prescription of synthetic harmaceutical of the dihydropyridine class-glutapyrone-together with drinking water during 6 months reduced the rate of malignant neoplasms from 26,5% in the control roup to 13% in the treated animals. In radiation-exposed rats that received lutapyrone there was a narrowing of spectrum of the emerged neoplasms (connectively-tissual tumors only as compared to the animals of the radiated control group, where blastomas of epithelium and lymphoid origin were also revealed. Low toxicity of lutapyrone and its anticarcinogenic action show the possibility of practical application of preparation for prevention radiation carcinogenesis.

  4. Two-dimensional HID light source radiative transfer using discrete ordinates method

    Science.gov (United States)

    Ghrib, Basma; Bouaoun, Mohamed; Elloumi, Hatem

    2016-08-01

    This paper shows the implementation of the Discrete Ordinates Method for handling radiation problems in High Intensity Discharge (HID) lamps. Therefore, we start with presenting this rigorous method for treatment of radiation transfer in a two-dimensional, axisymmetric HID lamp. Furthermore, the finite volume method is used for the spatial discretization of the Radiative Transfer Equation. The atom and electron densities were calculated using temperature profiles established by a 2D semi-implicit finite-element scheme for the solution of conservation equations relative to energy, momentum, and mass. Spectral intensities as a function of position and direction are first calculated, and then axial and radial radiative fluxes are evaluated as well as the net emission coefficient. The results are given for a HID mercury lamp on a line-by-line basis. A particular attention is paid on the 253.7 nm resonance and 546.1 nm green lines.

  5. The HAW-Project. Test disposal of highly radioactive radiation sources in the Asse salt mine. Final report

    International Nuclear Information System (INIS)

    In order to improve the final concept for the disposal of high-level radioactive waste (HAW) in boreholes drilled into salt formation plans were developed a couple of years ago for a full scale testing of the complete technical system of an underground repository. To satisfy the test objectives, thirty highly radioactive radiation sources were planned to be emplaced in six boreholes located in two test galleries at the 800-m-level in the Asse salt mine. A duration of testing of approximately five years was envisaged. Because of licensing uncertainties the German Federal Government decided on December 3rd, 1992 to stop all activities for the preparation of the test disposal immediately. In the course of the preparation of the test disposal, however, a system, necessary for handling of the radiation sources was developed and installed in the Asse salt mine and two non-radioactive reference tests with electrical heaters were started in November 1988. These tests served for the investigation of thermal effects in comparison to the planned radioactive tests. An accompanying scientific investigation programme performed in situ and in the laboratory comprises the estimation and observation of the thermal, radiation-induced, and mechanical interaction between the rock salt and the electrical heaters and the radiation sources, respectively. The laboratory investigations are carried out at Braunschweig (FRG), Petten (NL), Saclay (F) and Barcelona (E). As a consequence of the premature termination of the project the working programme was revised. The new programme agreed to by the project partners included a controlled shutdown of the heater tests in 1993 and a continuation of the laboratory activities until the end of 1994. (orig.)

  6. General relativistic radiation hydrodynamics of accretion flows - II. Treating stiff source terms and exploring physical limitations

    Science.gov (United States)

    Roedig, C.; Zanotti, O.; Alic, D.

    2012-10-01

    We present the implementation of an implicit-explicit (IMEX) Runge-Kutta numerical scheme for general relativistic (GR) hydrodynamics coupled to an optically thick radiation field in two existing GR-(magneto)hydrodynamics codes. We argue that the necessity of such an improvement arises naturally in most astrophysically relevant regimes where the optical thickness is high as the equations become stiff. By performing several simple 1D tests, we verify the codes' new ability to deal with this stiffness and show consistency. Then, still in one spatial dimension, we compute a luminosity versus accretion rate diagram for the set-up of spherical accretion on to a Schwarzschild black hole and find good agreement with previous work which included more radiation processes than we currently have available. Lastly, we revisit the supersonic Bondi-Hoyle-Lyttleton (BHL) accretion in two dimensions where we can now present simulations of realistic temperatures, down to T ˜ 106 K or less. Here we find that radiation pressure plays an important role, but also that these highly dynamical set-ups push our approximate treatment towards the limit of physical applicability. The main features of radiation hydrodynamics BHL flows manifest as (i) an effective adiabatic index approaching γeff ˜ 4/3; (ii) accretion rates two orders of magnitude lower than without radiation pressure, but still super-Eddington; (iii) luminosity estimates around the Eddington limit, hence with an overall radiative efficiency as small as ηBHL˜10-2; (iv) strong departures from thermal equilibrium in shocked regions; (v) no appearance of the flip-flop instability. We conclude that the current optically thick approximation to the radiation transfer does give physically substantial improvements over the pure hydro also in set-ups departing from equilibrium, and, once accompanied by an optically thin treatment, is likely to provide a fundamental tool for investigating accretion flows in a large variety of

  7. Development of a Tandem-Electrostatic-Quadrupole facility for Accelerator-Based Boron Neutron Capture Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kreiner, A.J., E-mail: kreiner@tandar.cnea.gov.ar [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, 1650 San Martin, Buenos Aires (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina)] [CONICET, Buenos Aires (Argentina); Castell, W. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, 1650 San Martin, Buenos Aires (Argentina); Di Paolo, H. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, 1650 San Martin, Buenos Aires (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina); Baldo, M. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, 1650 San Martin, Buenos Aires (Argentina); Bergueiro, J. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, 1650 San Martin, Buenos Aires (Argentina)] [CONICET, Buenos Aires (Argentina)

    2011-12-15

    We describe the present status of an ongoing project to develop a Tandem-ElectroStatic-Quadrupole (TESQ) accelerator facility for Accelerator-Based (AB)-BNCT. The project final goal is a machine capable of delivering 30 mA of 2.4 MeV protons to be used in conjunction with a neutron production target based on the {sup 7}Li(p,n){sup 7}Be reaction. The machine currently being constructed is a folded TESQ with a high-voltage terminal at 0.6 MV. We report here on the progress achieved in a number of different areas.

  8. Sources of ionizing radiation, radioactive or nuclear materials out of control. National system of response in Slovakia

    International Nuclear Information System (INIS)

    In this paper authors deals with the Customs inspection of radioactive materials - present situation as well as with situation after accession of the Slovak Republic process to European Union (EU). he actual response system to incidents with orphan sources or radioactive material occurring in metal scrap, illicit trafficking and disused sources out of control is laid down on the following scheme. The national strategy is aimed to establish a more effective responding system preventing further illegal trafficking with regard to the acceding process which will require for new member states joining EU proper arrangements in improving the safety of radiation sources over the life-cycle to ensure the effective functioning in the conditions of the Slovak Republic's membership in the European Union

  9. Seismic source mechanisms for quarry blasts: modelling observed Rayleigh and Love wave radiation patterns from a Texas quarry

    Science.gov (United States)

    McLaughlin, Keith L.; Bonner, Jessie L.; Barker, Terrance

    2004-01-01

    A theoretical understanding of the mechanisms by which quarry blasts excite seismic waves is useful in understanding how quarry blast discriminants may be transported from one region to another. An experiment in Texas with well-placed seismic stations and a cooperative blasting engineer has shed light on some of the physical mechanisms of seismic excitation at short periods (0.1-3 Hz). Azimuthal radiation patterns of the 0.2-3 Hz Rayleigh and Love waves are diagnostic of two proposed mechanisms for non-isotropic radiation from quarry blasts. Observations show that the Love and Rayleigh wave radiation patterns depend upon the orientation of the quarry benches. Two possible mechanisms for non-isotropic radiation are (1) the lateral throw of spalled material and (2) the presence of the topographic bench in the quarry. The spall of material can be modelled by vertical and horizontal forces applied to the free surface with time functions proportional to the derivative of the momentum of the spalled material. We use wavenumber integration synthetics to model the explosion plus spall represented by seismic moment tensor sources plus point forces. The resulting synthetics demonstrate that the magnitude of the SH (Love) compared with the SV (fundamental Rayleigh or Rg) in the short period band (0.5-3 Hz) may be explained by the spall mechanism. Nearly all of the available mass must participate in the spall with an average velocity of 2-5 m s-1 to provide sufficient impulse to generate the observed Love waves. Love wave radiation patterns from such a mechanism are consistent with the spall mechanism. We modelled the effects of the topographic bench using 3-D linear finite-difference calculations to compute progressive elastic wavefields from explosion sources behind the quarry bench. These 3-D calculations show SH radiation patterns consistent with observations while the SV radiation patterns are not consistent with observations. We find that the radiation patterns from the

  10. Investigation of the radiation shielding capacity of asphalt and sand for fast neutron sources

    International Nuclear Information System (INIS)

    The internal wall of the cavity of experimental assemblies, involved with high energy fusion neutrons, can be covered by an asphalt-sand layer for radiation protection purposes. The calculations have demonstrated that asphalt has a radiation protection capability superior to that of concrete, on equivalent weight basis. For an experimental cavity using a 10 (12) neutrons/sec neutron generator, the best structure has been found to be a 10% asphalt-90% red sand homogeneous mixture, against neutron + gamma energies, with a protection capability of more than 200% compared to the same thickness of a concrete structure. This work has proved that the local and cheap asphalt and sand can replace the relatively expensive concrete in constructing biological radiation shielding of experimental assemblies on fusion neutronics. 15 refs

  11. Solar Radiation Model for Development and Control of Solar Energy Sources

    Directory of Open Access Journals (Sweden)

    Dominykas Vasarevičius

    2016-06-01

    Full Text Available The model of solar radiation, which takes into account direct, diffused and reflected components of solar energy, has been presented. Model is associated with geographical coordinates and local time of every day of the year. It is shown that using analytic equations for modelling the direct component, it is possible to adopt it for embedded systems with low computational power and use in solar tracking applications. Reflected and diffused components are especially useful in determining the performance of photovoltaic modules in certain location and surroundings. The statistical method for cloud layer simulation based on local meteorological data is offered. The presented method can’t be used for prediction of weather conditions but it provides patterns of solar radiation in time comparable to those measured with pyranometer. Cloud layer simulation together with total solar radiation model is a useful tool for development and analysis of maximum power point tracking controllers for PV modules.

  12. Case studies in the application of probabilistic safety assessment techniques to radiation sources. Final report of a coordinated research project 2001-2003

    International Nuclear Information System (INIS)

    Radiation sources are used worldwide in many industrial and medical applications. In general, the safety record associated with their use has been very good. However, accidents involving these sources have occasionally resulted in unplanned exposures to individuals. When assessed prospectively, this type of exposure is termed a 'potential exposure'. The International Commission on Radiological Protection (ICRP) has recommended the assessment of potential exposures that may result from radiation sources and has suggested that probabilistic safety assessment (PSA) techniques may be used in this process. Also, Paragraph 2.13 of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) requires that the authorization process for radiation sources include an assessment of all exposures, including potential exposures, which may result from the use of a radiation source. In light of the ICRP's work described above, and the possibility that PSA techniques could be used in exposure assessments that are required by the BSS, the IAEA initiated a coordinated research project (CRP) to study the benefits and limitations of the application of PSA techniques to radiation sources. The results of this CRP are presented in this publication. It should be noted that these results are based solely on the work performed, and the conclusions drawn, by the research teams involved in this CRP. It is intended that international organizations involved in radiation protection will review the information in this report and will take account of it during the development of guidance and requirements related to the assessment of potential exposures from radiation sources. Also, it is anticipated that the risk insights obtained through the studies will be considered by medical practitioners, facility staff and management, equipment designers, and regulators in their safety management and risk evaluation activities. A draft

  13. Radiative neutron capture as a counting technique at pulsed spallation neutron sources: a review of current progress

    Science.gov (United States)

    Schooneveld, E. M.; Pietropaolo, A.; Andreani, C.; Perelli Cippo, E.; Rhodes, N. J.; Senesi, R.; Tardocchi, M.; Gorini, G.

    2016-09-01

    Neutron scattering techniques are attracting an increasing interest from scientists in various research fields, ranging from physics and chemistry to biology and archaeometry. The success of these neutron scattering applications is stimulated by the development of higher performance instrumentation. The development of new techniques and concepts, including radiative capture based neutron detection, is therefore a key issue to be addressed. Radiative capture based neutron detectors utilize the emission of prompt gamma rays after neutron absorption in a suitable isotope and the detection of those gammas by a photon counter. They can be used as simple counters in the thermal region and (simultaneously) as energy selector and counters for neutrons in the eV energy region. Several years of extensive development have made eV neutron spectrometers operating in the so-called resonance detector spectrometer (RDS) configuration outperform their conventional counterparts. In fact, the VESUVIO spectrometer, a flagship instrument at ISIS serving a continuous user programme for eV inelastic neutron spectroscopy measurements, is operating in the RDS configuration since 2007. In this review, we discuss the physical mechanism underlying the RDS configuration and the development of associated instrumentation. A few successful neutron scattering experiments that utilize the radiative capture counting techniques will be presented together with the potential of this technique for thermal neutron diffraction measurements. We also outline possible improvements and future perspectives for radiative capture based neutron detectors in neutron scattering application at pulsed neutron sources.

  14. HELIOS: An Open-Source, GPU-Accelerated Radiative Transfer Code For Self-Consistent Exoplanetary Atmospheres

    CERN Document Server

    Malik, Matej; Mendonça, João M; Grimm, Simon L; Lavie, Baptiste; Kitzmann, Daniel; Tsai, Shang-Min; Burrows, Adam; Kreidberg, Laura; Bedell, Megan; Bean, Jacob L; Stevenson, Kevin B; Heng, Kevin

    2016-01-01

    We present the open-source radiative transfer code named HELIOS, which is constructed for studying exoplanetary atmospheres. In its initial version, the model atmospheres of HELIOS are one-dimensional and plane-parallel, and the equation of radiative transfer is solved in the two-stream approximation with non-isotropic scattering. The opacities are computed with the opacity calculator HELIOS-K and converted to k-distribution tables by weighing the molecular abundances with analytical chemistry formulae. We validate HELIOS by comparing a model of GJ 1214b to that computed using COOLTLUSTY and from the work of Miller-Ricci & Fortney, and by performing several tests, where we find: model atmospheres with single-temperature layers struggle to converge to radiative equilibrium; k-distribution tables constructed with 1-10% in the synthetic spectra; and a diffusivity factor of 2 approximates well the exact radiative transfer solution in the limit of pure absorption. We construct "null-hypothesis" models (chemic...

  15. Radiative neutron capture as a counting technique at pulsed spallation neutron sources: a review of current progress.

    Science.gov (United States)

    Schooneveld, E M; Pietropaolo, A; Andreani, C; Perelli Cippo, E; Rhodes, N J; Senesi, R; Tardocchi, M; Gorini, G

    2016-09-01

    Neutron scattering techniques are attracting an increasing interest from scientists in various research fields, ranging from physics and chemistry to biology and archaeometry. The success of these neutron scattering applications is stimulated by the development of higher performance instrumentation. The development of new techniques and concepts, including radiative capture based neutron detection, is therefore a key issue to be addressed. Radiative capture based neutron detectors utilize the emission of prompt gamma rays after neutron absorption in a suitable isotope and the detection of those gammas by a photon counter. They can be used as simple counters in the thermal region and (simultaneously) as energy selector and counters for neutrons in the eV energy region. Several years of extensive development have made eV neutron spectrometers operating in the so-called resonance detector spectrometer (RDS) configuration outperform their conventional counterparts. In fact, the VESUVIO spectrometer, a flagship instrument at ISIS serving a continuous user programme for eV inelastic neutron spectroscopy measurements, is operating in the RDS configuration since 2007. In this review, we discuss the physical mechanism underlying the RDS configuration and the development of associated instrumentation. A few successful neutron scattering experiments that utilize the radiative capture counting techniques will be presented together with the potential of this technique for thermal neutron diffraction measurements. We also outline possible improvements and future perspectives for radiative capture based neutron detectors in neutron scattering application at pulsed neutron sources. PMID:27502571

  16. Radiation fields by intermediate-age stellar populations with binaries as ionizing sources of H II regions

    CERN Document Server

    Zhang, F; Cheng, L; Wang, L; Kang, X; Zhuang, Y; Han, Z

    2014-01-01

    Radiation fields emitted by O, B-type stars or young stellar populations (SPs) are generally considered as significant central ionizing sources (CISs) of classic H II regions. In our previous studies, we show that the inclusion of binary interactions in stellar population synthesis models can significantly increase the ultraviolet spectrum hardness and the number of ionizing photons of intermediate-age (IA, 7<~log(t/yr)<~8) SPs. In this work, we present photoionization models of H II regions ionized by radiation fields emitted by IA SPs, and show that radiation fields of IA SPs, including binary systems, are in theory possible candidates of significant CISs of classic H II regions. When radiation fields of IA SPs comprising binary systems are used as the CISs of classic H II regions, the theoretical strengths of a number of lines (such as [O III]4959', [S II]6716', etc.), weaker than observations, are raised; the border /selection-criterion lines, between star-forming galaxies and AGNs in the diagnostic...

  17. Greece: National Report on the implementation of the Code of Conduct for the safety and the security of radioactive sources and its Supplementary Guidance on the Import and Export of Radiation Sources

    International Nuclear Information System (INIS)

    The Greek Atomic Energy Commission (GAEC) is the national competent authority for radiation protection and nuclear safety. GAEC is a decentralized (autonomous) public service, having as mission the protection of the public, the workers and the environment from ionizing and artificially produced non-ionizing radiation. Greece, through GAEC, has submitted to IAEA its commitment to implement the Code of Conduct and its Supplementary Guidance on the Import and Export of Radioactive Sources. Radioactive sources are used for medical, industrial, research and educational applications in Greece; their activities range from a few Bq to TBq. There are several legislative, regulatory and enforcement measures in place for safety and security of the sources throughout their useful life, including provisions for the orphan sources, disused sources and HASS. Current national legislation considers security of radioactive sources as part of the radiation safety, imposing certain measures. HASS legislation refers explicitly to security aspect. The Greek legislation attributes the prime responsibility of the safe and secure management of radioactive sources to the license holder (licensee) through the respective license (operation license, radiation source possession & use license, etc.). For the every radiation sources a qualified person in charge is appointed, who is responsible against law and GAEC for the safety and security of the sources. GAEC maintains the national inventory of radioactive sources. GAEC performs inspections (with and without prior notification) on a regular basis (at least every 3 years) to all facilities. For the import and export of radiation sources to/from Greece from/to EU, the ANNEX I must be submitted and approved by the competent authorities prior to shipment. For HASS, the consent form must be submitted to the non-EU countries competent authorities prior to shipment. The import, export and transport of all radioactive sources are licensed by GAEC

  18. Elemental analysis of concrete samples using an accelerator-based PGNAA setup

    Science.gov (United States)

    Naqvi, A. A.; Nagadi, M. M.; Baghabra Al-Amoudi, Omar S.

    2004-09-01

    Elemental analysis of concrete samples was carried out using an accelerator-based prompt gamma ray neutron activation analysis (PGNAA) setup. The gamma rays were produced via the capture of thermal neutron in the concrete sample. The prompt gamma ray yield was measured for 12 cm long concrete samples as a function of sample radius over a range of 6-11.5 cm radii. The optimum yield of the prompt gamma rays from the concrete sample was measured from a sample with 11.5 cm radius. The gamma ray yield was also calculated for 12 cm long concrete samples with 6-11.5 cm radius using Monte Carlo simulations. The experimental results were in excellent agreement with the calculated yield of the prompt gamma rays from the samples. Result of this study has shown the useful application of an accelerator-based PGNAA setup in elemental analysis of concrete sample. The facility can be further used to determine the chloride and sulfate concentrations in concrete samples for corrosion studies of reinforcement steel in concrete structures.

  19. Elemental analysis of concrete samples using an accelerator-based PGNAA setup

    International Nuclear Information System (INIS)

    Elemental analysis of concrete samples was carried out using an accelerator-based prompt gamma ray neutron activation analysis (PGNAA) setup. The gamma rays were produced via the capture of thermal neutron in the concrete sample. The prompt gamma ray yield was measured for 12 cm long concrete samples as a function of sample radius over a range of 6-11.5 cm radii. The optimum yield of the prompt gamma rays from the concrete sample was measured from a sample with 11.5 cm radius. The gamma ray yield was also calculated for 12 cm long concrete samples with 6-11.5 cm radius using Monte Carlo simulations. The experimental results were in excellent agreement with the calculated yield of the prompt gamma rays from the samples. Result of this study has shown the useful application of an accelerator-based PGNAA setup in elemental analysis of concrete sample. The facility can be further used to determine the chloride and sulfate concentrations in concrete samples for corrosion studies of reinforcement steel in concrete structures

  20. Pedestrian movement analysis in transfer station corridor: Velocity-based and acceleration-based

    Science.gov (United States)

    Ji, Xiangfeng; Zhang, Jian; Hu, Yongkai; Ran, Bin

    2016-05-01

    In this paper, pedestrians are classified into aggressive and conservative ones by their temper. Aggressive pedestrians' walking through crowd in transfer station corridor is analyzed. Treating pedestrians as particles, this paper uses the modified social force model (MSFM) as the building block, where forces involve self-driving force, repulsive force and friction force. The proposed model in this paper is a discrete model combining the MSFM and cellular automata (CA) model, where the updating rules of the CA are redefined with MSFM. Due to the continuity of values generated by the MSFM, we use the fuzzy logic to discretize the continuous values into cells pedestrians can move in one step. With the observation that stimulus around pedestrians influences their acceleration directly, an acceleration-based movement model is presented, compared to the generally reviewed velocity-based movement model. In the acceleration-based model, a discretized version of kinematic equation is presented based on the acceleration discretized with fuzzy logic. In real life, some pedestrians would rather keep their desired speed and this is also mimicked in this paper, which is called inertia. Compared to the simple triangular membership function, a trapezoidal membership function and a piecewise linear membership function are used to capture pedestrians' inertia. With the trapezoidal and the piecewise linear membership function, many overlapping scenarios should be carefully handled and Dubois and Prade's four-index method is used to completely describe the relative relationship of fuzzy quantities. Finally, a simulation is constructed to demonstrate the effect of our model.