WorldWideScience

Sample records for high-energy particle radiation

  1. High energy particle accelerators as radiation Sources

    Energy Technology Data Exchange (ETDEWEB)

    Abdelaziz, M E [National Center for Nuclear Safety and Radiation Vontrol, Atomic Energy Authority, Cairo (Egypt)

    1997-12-31

    Small accelerators in the energy range of few million electron volts are usually used as radiation sources for various applications, like radiotherapy, food irradiation, radiation sterilization and in other industrial applications. High energy accelerators with energies reaching billions of electron volts also find wide field of applications as radiation sources. Synchrotrons with high energy range have unique features as radiation sources. This review presents a synopsis of cyclic accelerators with description of phase stability principle of high energy accelerators with emphasis on synchrotrons. Properties of synchrotron radiation are given together with their applications in basic and applied research. 13 figs.,1 tab.

  2. Radiation safety aspects of high energy particle accelerators

    International Nuclear Information System (INIS)

    Subbaiah, K.V.

    2007-01-01

    High-energy accelerators are widely used for various applications in industry, medicine and research. These accelerators are capable of accelerating both ions and electrons over a wide range of energy and subsequently are made to impinge on the target materials. Apart from generating intended reactions in the target, these projectiles can also generate highly penetrating radiations such as gamma rays and neutrons. Over exposure to these radiations will cause deleterious effects on the living beings. Various steps taken to protect workers and general public from these harmful radiations is called radiation safety. The primary objective in establishing permissible values for occupational workers is to keep the radiation worker well below a level at which adverse effects are likely to be observed during one's life time. Another objective is to minimize the incidence of genetic effects for the population as a whole. Today's presentation on radiation safety of accelerators will touch up on the following sub-topics: Types of particle accelerators and their applications; AERB directives on dose limits; Radiation Source term of accelerators; Shielding Design-Use of Transmission curves and Tenth Value layers; Challenges for accelerator health physicists

  3. Higgs radiation off top particles in high-energy e+e- colliders

    International Nuclear Information System (INIS)

    Djouadi, A.; Technische Hochschule Aachen; Kalinowski, J.; Zerwas, P.M.

    1991-10-01

    Higgs particles can be radiated off heavy top quarks which will be produced copiously in high energy e + e - colliders. This process can be used to measure the Higgs-top quark coupling. We present the cross section for the production of Higgs bosons in the Standard Model. In addition we have studied the production of neutral and charged Higgs particles in association with heavy fermions in the Minimal Supersymmetric Standard Model. (orig.)

  4. Development of High Energy Particle Detector for the Study of Space Radiation Storm

    Directory of Open Access Journals (Sweden)

    Gyeong-Bok Jo

    2014-09-01

    Full Text Available Next Generation Small Satellite-1 (NEXTSat-1 is scheduled to launch in 2017 and Instruments for the Study of Space Storm (ISSS is planned to be onboard the NEXTSat-1. High Energy Particle Detector (HEPD is one of the equipment comprising ISSS and the main objective of HEPD is to measure the high energy particles streaming into the Earth radiation belt during the event of a space storm, especially, electrons and protons, to obtain the flux information of those particles. For the design of HEPD, the Geometrical Factor was calculated to be 0.05 to be consistent with the targets of measurement and the structure of telescope with field of view of 33.4° was designed using this factor. In order to decide the thickness of the detector sensor and the classification of the detection channels, a simulation was performed using GEANT4. Based on the simulation results, two silicon detectors with 1 mm thickness were selected and the aluminum foil of 0.05 mm is placed right in front of the silicon detectors to shield low energy particles. The detection channels are divided into an electron channel and two proton channels based on the measured LET of the particle. If the measured LET is less than 0.8 MeV, the particle belongs to the electron channel, otherwise it belongs to proton channels. HEPD is installed in the direction of 0°,45°,90° against the along-track of a satellite to enable the efficient measurement of high energy particles. HEPD detects electrons with the energy of 0.1 MeV to several MeV and protons with the energy of more than a few MeV. Thus, the study on the dynamic mechanism of these particles in the Earth radiation belt will be performed.

  5. Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

    Science.gov (United States)

    Higuchi, Yoshinori; Nelson, Gregory A.; Vazquez, Marcelo; Laskowitz, Daniel T.; Slater, James M.; Pearlstein, Robert D.

    2002-01-01

    Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. METHODS: Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. ROTAROD TEST: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. OPEN FIELD TEST: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. MORRIS WATER MAZE: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. CONCLUSIONS: These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the CNS. ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process.

  6. Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

    International Nuclear Information System (INIS)

    Higuchi, Yoshinori; Nelson, G.A.; Slater, J.M.; Pearlstein, R.D.; Laskowitz, D.T.

    2002-01-01

    Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. Rotarod test: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. Open field test: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. Morris water maze: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the central nervous system (CNS). ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process. (author)

  7. Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

    Energy Technology Data Exchange (ETDEWEB)

    Higuchi, Yoshinori; Nelson, G.A.; Slater, J.M.; Pearlstein, R.D. [Loma Linda Univ., CA (United States). Medical Center; Vazquez, M. [Brookhaven National Lab., Upton, NY (United States); Laskowitz, D.T. [Duke Univ., Durham, NC (United States). Medical Center

    2002-12-01

    Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. Rotarod test: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. Open field test: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. Morris water maze: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the central nervous system (CNS). ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process. (author)

  8. HEPD on NEXTSat-1: A High Energy Particle Detector for Measurements of Precipitating Radiation Belt Electrons

    Science.gov (United States)

    Sohn, Jongdae; Lee, Jaejin; Min, Kyoungwook; Lee, Junchan; Lee, Seunguk; Lee, Daeyoung; Jo, Gyeongbok; Yi, Yu; Na, Gowoon; Kang, Kyung-In; Shin, Goo-Hwan

    2018-05-01

    Radiation belt particles of the inner magnetosphere precipitate into the atmosphere in the subauroral regions when they are pitch-angle scattered into the loss cone by wave-particle interactions. Such particle precipitations are known to be especially enhanced during space storms, though they can also occur during quiet times. The observed characteristics of precipitating electrons can be distinctively different, in their time series as well as in their spectra, depending on the waves involved. The present paper describes the High Energy Particle Detector (HEPD) on board the Next Generation Small Satellite-1 (NEXTSat-1), which will measure these radiation belt electrons from a low-Earth polar orbit satellite to study the mechanisms related to electron precipitation in the sub-auroral regions. The HEPD is based on silicon barrier detectors and consists of three telescopes that are mounted on the satellite to have angles of 0°. 45°, and 90°, respectively with the local geomagnetic field during observations. With a high time resolution of 32 Hz and a high spectral resolution of 11 channels over the energy range from 350 keV to 2 MeV, together with the pitch angle information provided by the three telescopes, HEPD is capable of identifying physical processes, such as microbursts and dust-side relativistic electron precipitation (DREP) events associated with electron precipitations. NextSat-1 is scheduled for launch in early 2018.

  9. Scintillating plastic optical fiber radiation detectors in high energy particle physics

    International Nuclear Information System (INIS)

    Bross, A.D.

    1991-01-01

    We describe the application of scintillating optical fiber in instrumentation for high energy particle physics. The basic physics of the scintillation process in polymers is discussed first and then we outline the fundamentals of scintillating fiber technology. Fiber performance, optimization, and characterization measurements are given. Detector applications in the areas of particle tracking and particle energy determination are then described. 13 refs., 12 figs

  10. High energy radiation fluences in the ISS-USLab: Ion discrimination and particle abundances

    International Nuclear Information System (INIS)

    Zaconte, Veronica; Casolino, Marco; Di Fino, Luca; La Tessa, Chiara; Larosa, Marianna; Narici, Livio; Picozza, Piergiorgio

    2010-01-01

    The ALTEA (Anomalous Long Term Effects on Astronauts) detector was used to characterize the radiation environment inside the USLab of the International Space Station (ISS), where it measured the abundances of ions from Be to Fe. We compare the ALTEA results with Alteino results obtained in the PIRS module of the Russian segment of the ISS, and normalize to the high energy Si abundances given by Simpson. These are the first particle spectral measurements, which include ions up to Fe, performed in the USLab. The small differences observed between those made inside the USLab and the Simpson abundances can be attributed to the transport through the spacecraft hull. However, the low abundance of Fe cannot be attributed to only this process.

  11. High energy radiation detector

    International Nuclear Information System (INIS)

    Vosburgh, K.G.

    1975-01-01

    The high energy radiation detector described comprises a set of closely spaced wedge reflectors. Each wedge reflector is composed of three sides forming identical isoceles triangles with a common apex and an open base forming an equilateral triangle. The length of one side of the base is less than the thickness of the coat of material sensitive to high energy radiation. The wedge reflectors reflect the light photons spreading to the rear of the coat in such a way that each reflected track is parallel to the incident track of the light photon spreading rearwards. The angle of the three isosceles triangles with a common apex is between 85 and 95 deg. The first main surface of the coat of high energy radiation sensitive material is in contact with the projecting edges of the surface of the wedge reflectors of the reflecting element [fr

  12. Dynamic chaos phenomenon and coherent radiation accompanying high energy particle motion through crystals

    International Nuclear Information System (INIS)

    Akhiezer, A.I.; Truten', V.I.; Shul'ga, N.F.

    1991-01-01

    A crystal has a regular structure, therefore every motion in such a structure seems to be regular. However, it is not actually so and even in perfect crystals the particle motion may be either regular or chaotic. Everything depends on the number of integrals of motion determining a particle trajectory. The character of particle motion in a crystal, i.e. its regularity or chaoticity, affects many physical processes accompanying the particle's motion. In this paper we shall consider the effect of dynamic chaos on the coherent radiation of fast particles in a crystal. We also consider the validity conditions of coherent radiation theory results, the role of the second and higher Born approximations in the radiation theory of fast particles in crystals, the continuous string approximation in this theory, the coherent radiation in the model of random strings, and the multiple scattering effect on the coherent radiation. (author)

  13. A novel transition radiation detector utilizing superconducting microspheres for measuring the energy of relativistic high-energy charged particles

    International Nuclear Information System (INIS)

    Yuan, Luke C.L.; Chen, C.P.; Huang, C.Y.; Lee, S.C.; Waysand, G.; Perrier, P.; Limagne, D.; Jeudy, V.; Girard, T.

    2000-01-01

    A novel transition radiation detector (TRD) utilizing superheated superconducting microspheres of tin of 22-26, 27-32 and 32-38 μm in diameter, respectively, has been constructed which is capable of measuring accurately the energy of relativistic high-energy charged particles. The test has been conducted in a high-energy electron beam facility at the CERN PS in the energy range of 1-10 GeV showing an energy dependence of the TR X-ray photon produced and hence the value γ=E/mc 2 of the charged particle

  14. Dosimetry of high energy radiation

    CERN Document Server

    Sahare, P D

    2018-01-01

    High energy radiation is hazardous to living beings and a threat to mankind. The correct estimation of the high energy radiation is a must and a single technique may not be very successful. The process of estimating the dose (the absorbed energy that could cause damages) is called dosimetry. This book covers the basic technical knowledge in the field of radiation dosimetry. It also makes readers aware of the dangers and hazards of high energy radiation.

  15. Investigation of radiation defects in InSb formed by charged high energy nuclear particles

    International Nuclear Information System (INIS)

    Vikhlij, G.A.; Karpenko, A.Ya.; Litovchenko, P.G.; Tarabrova, L.I.; Groza, A.A.

    1990-01-01

    A possibility of creation of high concentrations of radiation defects in the bulk of InSb samples by 47 MeV protons and 80 MeV alpha particles is considered. Dose dependences of electroconductivity, optical absorption spectra as well as temperature and field relations of galvanomagnetic properties of samples with defects are investigated. Annealing stages and electrical properties of defects annealed at these stages are determined. 17 refs.; 7 figs

  16. A guide to radiation and radioactivity levels near high energy particle accelerators

    International Nuclear Information System (INIS)

    Sullivan, A.H.

    1992-01-01

    An estimate of likely radiation and radioactivity levels is needed at the design stage of an accelerator for deciding the radiation safety features to be incorporated in the infrastructure of the machine and for predicting where radiation damage possibilities will have to be taken into account. Both these aspects can have a significant influence on the machine layout and cost. Failure to make a reasonable assessment at the right time may have far reaching consequences for future costs. The purpose of this guide is to bring together basic data and methods that have been found useful in assessing radiation situations around accelerators and to provide a practical means of arriving at the radiation and induced radioactivity levels that could occur under a wide variety of circumstances. An attempt is made to present the information in a direct and unambiguous way with sufficient confidence that the necessity for large safety factors is avoided. In many cases assumptions and simplifications have been made and reliance placed on extrapolating from experimental data into regions where the basic physics is too complicated to make meaningful absolute calculations. Wherever possible such extrapolations have been tied to real or otherwise acceptable data originating from independent sources. (Author)

  17. High-energy particle diffraction

    International Nuclear Information System (INIS)

    Barone, V.; Predazzi, E.

    2002-01-01

    This monograph gives a comprehensive and up-to-date overview of soft and hard diffraction processes in strong interaction physics. The first part covers the general formalism (the optical analogy, the eikonal picture, high-energy kinematics, S-matrix theory) and soft hadron-hadron scattering (including the Regge theory) in a complete and mature presentation. It can be used as a textbook in particle physics classes. The remainder of the book is devoted to the 'new diffraction': the pomeron in QCD, low-x physics, diffractive deep inelastic scattering and related processes, jet production etc. It presents recent results and experimental findings and their phenomenological interpretations. This part addresses graduate students as well as researchers. (orig.)

  18. Ultrastructural findings in the brain of fruit flies (Drosophila melanogaster) and mice exposed to high-energy particle radiation

    International Nuclear Information System (INIS)

    D'Amelio, F.; Kraft, L.M.; D'Antoni-D'Amelio, E.; Benton, E.V.; Miquel, J.

    1984-01-01

    Effects of high energy, heavy particle (HZE) radiation were studied in the brain of the fruit fly (Drosophila melanogaster) exposed to argon (40Ar) or krypton (84Kr) ions. In the flies exposed to argon the fluence ranged from 6 X 10(4) to 8 X 10(7) particles/cm2. The insects were killed 35 days after exposure. Extensive tissue fragmentation was observed at the higher fluence employed. At fluences ranging from 5 X 10(6) (one hit/two cell bodies) to 9 X 10(4) (one hit/90 cell bodies) particles/cm2, swelling of the neuronal cytoplasm and focally fragmented membranes was observed. Marked increase of glial lamellae around nerve cell processes was seen at fluences ranging from one hit/six to one hit/135 cell bodies. In the flies irradiated with krypton, the fluences employed were 5.8 X 10(3) and 2.2 X 10(6) particles/cm2. Acute and late effects were evaluated. In the flies killed 36 hours after exposure (acute effects) to either fluence, glycogen particles were found in the neuroglial compartment. The granules were no longer present in flies killed 35 days later (late effects). From these studies it appears that the Drosophila brain is a useful model to investigate radiation damage to mature neurons, neuroglia, and therefore, to the glio-neuronal metabolic unit. In a separate study, the synaptic profiles of the neuropil in layers II-III of the frontal cerebral cortex of anesthesized adult LAFl mice were quantitatively appraised after exposure to argon (40Ar) particles. The absorbed dose ranged from 0.05 to 5 gray (Gy) plateau. It was determined that the sodium pentobarbital anesthesia per se results in a significant decrease in synaptic profile length one day after anesthetization, with return to normal values after 2-28 days. Irradiation with 0.05-5 Gy argon particles significantly inhibited the synaptic shortening effect of anesthesia at one day after exposure

  19. Kinetic Modeling of Radiative Turbulence in Relativistic Astrophysical Plasmas: Particle Acceleration and High-Energy Flares

    Science.gov (United States)

    Wise, John

    In the near future, next-generation telescopes, covering most of the electromagnetic spectrum, will provide a view into the very earliest stages of galaxy formation. To accurately interpret these future observations, accurate and high-resolution simulations of the first stars and galaxies are vital. This proposal is centered on the formation of the first galaxies in the Universe and their observational signatures in preparation for these future observatories. This proposal has two overall goals: 1. To simulate the formation and evolution of a statistically significant sample of galaxies during the first billion years of the Universe, including all relevant astrophysics while resolving individual molecular clouds, in various cosmological environments. These simulations will utilize a sophisticated physical model of star and black hole formation and feedback, including radiation transport and magnetic fields, which will lead to the most realistic and resolved predictions for the early universe; 2. To predict the observational features of the first galaxies throughout the electromagnetic spectrum, allowing for optimal extraction of galaxy and dark matter halo properties from their photometry, imaging, and spectra; The proposed research plan addresses a timely and relevant issue to theoretically prepare for the interpretation of future observations of the first galaxies in the Universe. A suite of adaptive mesh refinement simulations will be used to follow the formation and evolution of thousands of galaxies observable with the James Webb Space Telescope (JWST) that will be launched during the second year of this project. The simulations will have also tracked the formation and death of over 100,000 massive metal-free stars. Currently, there is a gap of two orders of magnitude in stellar mass between the smallest observed z > 6 galaxy and the largest simulated galaxy from "first principles", capturing its entire star formation history. This project will eliminate this

  20. Individual Dosimetry for High Energy Radiation Fields

    International Nuclear Information System (INIS)

    Spurny, F.

    1999-01-01

    The exposure of individuals on board aircraft increased interest in individual dosimetry in high energy radiation fields. These fields, both in the case of cosmic rays as primary radiation and at high energy particle accelerators are complex, with a large diversity of particle types, their energies, and linear energy transfer (LET). Several already existing individual dosemeters have been tested in such fields. For the component with high LET (mostly neutrons) etched track detectors were tested with and without fissile radiators, nuclear emulsions, bubble detectors for both types available and an albedo dosemeter. Individual dosimetry for the low LET component has been performed with thermoluminescent detectors (TLDs), photographic film dosemeters and two types of electronic individual dosemeters. It was found that individual dosimetry for the low LET component was satisfactory with the dosemeters tested. As far as the high LET component is concerned, there are problems with both the sensitivity and the energy response. (author)

  1. Particle accelerators and lasers high energy sources

    International Nuclear Information System (INIS)

    Watteau, J.P.

    1985-04-01

    Particle accelerators and lasers are to-day precious devices for physicist and engineer. Their performance and scope do not stop growing. Producing thin beams of high energy particles or photons, they are able to be very high energy sources which interact strongly with matter. Numerous applications use them: research, industry, communication, medicine, agroalimentary, defence, and soon. In this note, their operation principles are described and some examples of their use as high energy sources are given [fr

  2. Radiation monitoring in high energy research facility

    International Nuclear Information System (INIS)

    Miyajima, Mitsuhiro

    1975-01-01

    In High Energy Physics Research Laboratory, construction of high energy proton accelerator is in progress. The accelerator is a cascaded machine comprising Cockcroft type (50 keV), linac (20 MeV), booster synchrotron (500 MeV), and synchrotron (8-12 GeV). Its proton beam intensity is 1x10 13 photons/pulse, and acceleration is carried out at the rate of every 2 minutes. The essential problems of radiation control in high energy accelerators are those of various radiations generated secondarily by proton beam and a number of induced radiations simultaneously originated with such secondary particles. In the Laboratory, controlled areas are divided into color-coded four regions, red, orange, yellow and green, based on each dose-rate. BF 3 counters covered with thick paraffin are used as neutron detectors, and side-window GM tubes, NaI (Tl) scintillators and ionization chambers as γ-detectors. In red region, however, ionization chambers are applied to induced radiation detection, and neutrons are not monitored. NIM standards are adopted for the circuits of all above monitors considering easy maintenance, economy and interchangeability. Notwithstanding the above described systems, these monitors are not sufficient to complete the measurement of whole radiations over wide energy region radiated from the accelerators. Hence separate radiation field measurement is required periodically. An example of the monitoring systems in National Accelerator Laboratory (U.S.) is referred at the last section. (Wakatsuki, Y.)

  3. Characteristics of background radiation behind one-dimensional radiation shielding of high-energy particle beams; Kharakteristiki fonovogo izlucheniya za odnomernymi radiatsionnymi zashchitami puchkov vysokoehnergeticheskikh chastits

    Energy Technology Data Exchange (ETDEWEB)

    Gorbatkov, D V; Kryuchkov, V P

    1994-12-31

    The calculational investigations of component, spatial and energy distributions of background radiation behind radiation shielding of high-energy hadron beams were carried out. The relations between different ingredients of radiation have been obtained. The numerous data of spatial and energy distribution of protons, neutrons, pions and photons in homogeneous and heterogeneous shielding from concrete and iron, presented in the paper, can be used as a reference data. 23 refs., 50 figs.

  4. Experimental microdosimetry in high energy radiation fields

    International Nuclear Information System (INIS)

    Spurny, F.; Bednar, J.; Vlcek, B.; Bottollier-Depois, J.-F.; Molokanov, A.G.

    2000-01-01

    To determine microdosimetric characteristics in the beams and fields of high energy panicles with the goal, also, to compare the classical method of experimental microdosimetry, a tissue equivalent low pressure proportional counter (TEPC) with the linear energy transfer (LET) spectrometer based on a chemically etched polyallyldiglycolcarbonate as a track etched detector (TED). To test the use of TED LET spectrometer in the conditions, where the use or TEPC is not possible (high energy charged particle beams at high dose rates). The results obtained with the TEPC NAUSICAA were used in this work to compare them with other data. This TEPC measures directly the linear energy in the interval between 0.15 and 1500 keV/μm in tissue, the low gas pressure (propan based TE mixture) permits to simulate a tissue element of about 3 μm. It can be used in the fields with instantaneous dose equivalent rates between 1 μSv/hour and 1 mSv/ hour. TED LET spectrometer developed to determine LET spectra between 10 and 700 keV/μm in tissue. Primarily, track-to-bulk etch rate ratios are determined through the track parameters measurements, the spectra of these ratios are convened to LET spectra using the calibration curve established by means of heavy charge panicles. The critical volume of thi spectrometer is supposed to be a few nm. There is no limit of use for the dose rate, the background tracks limit the lowest threshold to about 1 mSv, the overlapping of tracks (the highest one) to 100 mSv. Both experimental microdosimetry methods have been used in on board aircraft radiation fields, in on-Earth high energy radiation reference fields, and in the beams of protons with energies up to 300 MeV (Dubna, Moscow, Loma Linda). First, it should be emphasized, that in all high energy radiation fields studied, we concentrated our analysis on the region, where both methods overlap, i.e. between 10 and 1000 keV/μm in tissue. It should be also stressed, that the events observed in this region

  5. Studies in theorectical high energy particles physics

    International Nuclear Information System (INIS)

    Aratyn, H.; Keung, Wai-Yee; Panigrahi, P.; Sukhatme, U.

    1990-02-01

    This paper discusses the research being done at the University of Illinois in theoretical high energy physics. Some areas discussed are string models, collider physics, symmetries in gauge theories, sigma model, radiative decay of mesons, supersymmetry, superconducting, and hydroproduction of charm

  6. High energy radiation from neutron stars

    International Nuclear Information System (INIS)

    Ruderman, M.

    1985-04-01

    Topics covered include young rapidly spinning pulsars; static gaps in outer magnetospheres; dynamic gaps in pulsar outer magnetospheres; pulse structure of energetic radiation sustained by outer gap pair production; outer gap radiation, Crab pulsar; outer gap radiation, the Vela pulsar; radioemission; and high energy radiation during the accretion spin-up of older neutron stars. 26 refs., 10 figs

  7. Power Supplies for High Energy Particle Accelerators

    Science.gov (United States)

    Dey, Pranab Kumar

    2016-06-01

    The on-going research and the development projects with Large Hadron Collider at CERN, Geneva, Switzerland has generated enormous enthusiasm and interest amongst all to know about the ultimate findings on `God's Particle'. This paper has made an attempt to unfold the power supply requirements and the methodology adopted to provide the stringent demand of such high energy particle accelerators during the initial stages of the search for the ultimate particles. An attempt has also been made to highlight the present status on the requirement of power supplies in some high energy accelerators with a view that, precautionary measures can be drawn during design and development from earlier experience which will be of help for the proposed third generation synchrotron to be installed in India at a huge cost.

  8. Particle physics experiments at high energy colliders

    International Nuclear Information System (INIS)

    Hauptman, John

    2011-01-01

    Written by one of the detector developers for the International Linear Collider, this is the first textbook for graduate students dedicated to the complexities and the simplicities of high energy collider detectors. It is intended as a specialized reference for a standard course in particle physics, and as a principal text for a special topics course focused on large collider experiments. Equally useful as a general guide for physicists designing big detectors. (orig.)

  9. Superconductivity in high energy particle accelerators

    International Nuclear Information System (INIS)

    Schmueser, P.

    2002-08-01

    The basics of superconductivity are outlined with special emphasis on the features which are relevant for the application in magnets and radio frequency cavities for high energy particle accelerators. The special properties of superconducting accelerator magnets are described in detail: design principles, magnetic field calculations, magnetic forces, quench performance, persistent magnetization currents and eddy currents. The design principles and basic properties of superconducting cavities are explained as well as the observed performance limitations and the countermeasures. The ongoing research efforts towards maximum accelerating fields are addressed and the coupling of radio frequency power to the particle beam is treated. (orig.)

  10. Particle identification methods in High Energy Physics

    Energy Technology Data Exchange (ETDEWEB)

    Va' Vra, J.

    2000-01-27

    This paper deals with two major particle identification methods: dE/dx and Cherenkov detection. In the first method, the authors systematically compare existing dE/dx data with various predictions available in the literature, such as the Particle Data group recommendation, and judge the overall consistency. To my knowledge, such comparison was not done yet in a published form for the gaseous detectors used in High-Energy physics. As far as the second method, there are two major Cherenkov light detection techniques: the threshold and the Ring imaging methods. The authors discuss the recent trend in these techniques.

  11. High energy model for irregular absorbing particles

    International Nuclear Information System (INIS)

    Chiappetta, Pierre.

    1979-05-01

    In the framework of a high energy formulation of relativistic quantum scattering a model is presented which describes the scattering functions and polarization of irregular absorbing particles, whose dimensions are greater than the incident wavelength. More precisely in the forward direction an amplitude parametrization of eikonal type is defined which generalizes the usual diffraction theory, and in the backward direction a reflective model is used including a shadow function. The model predictions are in good agreement with the scattering measurements off irregular compact and fluffy particles performed by Zerull, Giese and Weiss (1977)

  12. Biological effects of high-energy radiation

    International Nuclear Information System (INIS)

    Curtis, S.B.

    1976-01-01

    The biological effects of high-energy radiation are reviewed, with emphasis on the effects of the hadronic component. Proton and helium ion effects are similar to those of the more conventional and sparsely ionizing x- and γ-radiation. Heavy-ions are known to be more biologically effective, but the long term hazard from accumulated damage has yet to be assessed. Some evidence of widely varying but dramatically increased effectiveness of very high-energy (approximately 70 GeV) hadron beams is reviewed. Finally, the importance of the neutron component in many situations around high-energy accelerators is pointed out

  13. Studies in theoretical high energy particle physics

    International Nuclear Information System (INIS)

    Aratyn, H.; Brekke, L.; Keung, Wai-Yee; Sukhatme, U.

    1993-01-01

    Theoretical work on the following topics is briefly summarized: symmetry structure of conformal affine Toda model and KP hierarchy; solitons in the affine Toda and conformal affine Toda models; classical r-matrices and Poisson bracket structures on infinite-dimensional groups; R-matrix formulation of KP hierarchies and their gauge equivalence; statistics of particles and solitons; charge quantization in the presence of an Alice string; knotting and linking of nonabelian flux; electric dipole moments; neutrino physics in gauge theories; CP violation in the high energy colliders; supersymmetric quantum mechanics; parton structure functions in nuclei; dual parton model. 38 refs

  14. Radiographic imaging system for high energy radiation

    International Nuclear Information System (INIS)

    1975-01-01

    A radiographic imaging system for high energy radiation is described utilizing a detector of such radiation and a mask having regions relatively transparent to such radiation and interspersed among regions relatively opaque to such radiation. A relative motion is imparted between the mask and the detector, the detector providing a time varying signal in response to the incident radiation and in response to the relative motion. The time varying signal provides, with the aid of a decoder, an image of a source of such radiation

  15. Radiographic imaging system for high energy radiation

    International Nuclear Information System (INIS)

    Barrett, H.H.

    1976-01-01

    A radiographic imaging system for high energy radiation utilizing a detector of such radiation and a mask having regions relatively transparent to such radiation interspersed among regions relatively opaque to such radiation is described. A relative motion is imparted between the mask and the detector, the detector providing a time varying signal in response to the incident radiation and in response to the relative motion. The time varying signal provides, with the aid of a decoder, an image of a source of such radiation

  16. Effect of quantum fluctuations of synchrotron radiation on the dynamics of particles in high-energy microtrons

    International Nuclear Information System (INIS)

    Bessonov, E.G.

    1987-01-01

    Crosbie has demonstrated numerically that the effect of quantum fluctuation of synchrotron radiation on the beam emittance becomes significant in microtrons for an energy of more than 1 GeV. In this paper the authors give analytic expressions that describe this phenomenon and analyze these expressions

  17. Radiation protection around high energy proton accelerators

    International Nuclear Information System (INIS)

    Bourgois, L.

    1996-01-01

    Proton accelerators are intense radiation sources because of the particle beam itself, secondary radiation and structure activation. So radiation protection is required around these equipment during running time but even during downtime. This article presents some estimated values about structure and air activation and applies the Moyer model to get dose rate behind shielding. (A.C.)

  18. High energy radiation in cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1959-10-15

    Certain basic recommendations on the use of supervoltage radiation and radioisotope teletherapy in the treatment of malignant growths have been made by an expert study group which met in Vienna in August this y ear. The group, convened jointly by the International Atomic Energy Agency and the World Health Organization, was composed of 20 radiotherapists and radiation physicists from 12 countries. High energy radiation, used in the treatment of malignant tumours, can be either in the form of gamma- or X-rays or in the form of beams of accelerated electrons. The source of radiation is kept at a certain distance from the patient. The study group was agreed on the value of supervoltage radiotherapy, including gamma-ray and high voltage x-ray therapy as well as electron beam therapy. The required gamma radiation can be obtained from large sources of radioactive materials like cobalt 60 or caesium 137, while electron beams are produced by high voltage accelerators. The experts considered the sources in four broad categories: large supervoltage units, intermediate units, small isotope units and units of electron beams or very high energy x-rays. Each group of source was described including its usage. The experts made it clear that while supervoltage radiation should be a part of an organized radiotherapy department, the radiation facilities at any particular establishment should not be of the supervoltage type alone. The high energy facilities could be fruitfully used only when there was a background of general radiotherapy. The group emphasized that supervoltage radiotherapy, in common with other forms of radiotherapy, should be conducted only by adequately trained and qualified personnel, including radiation physicists, and specified the training and qualifications required of such personnel. It was felt that specialized training was one of the main requirements at the present stage and the training programmes of IAEA and WHO should be utilized extensively for this

  19. High energy radiation in cancer treatment

    International Nuclear Information System (INIS)

    1959-01-01

    Certain basic recommendations on the use of supervoltage radiation and radioisotope teletherapy in the treatment of malignant growths have been made by an expert study group which met in Vienna in August this y ear. The group, convened jointly by the International Atomic Energy Agency and the World Health Organization, was composed of 20 radiotherapists and radiation physicists from 12 countries. High energy radiation, used in the treatment of malignant tumours, can be either in the form of gamma- or X-rays or in the form of beams of accelerated electrons. The source of radiation is kept at a certain distance from the patient. The study group was agreed on the value of supervoltage radiotherapy, including gamma-ray and high voltage x-ray therapy as well as electron beam therapy. The required gamma radiation can be obtained from large sources of radioactive materials like cobalt 60 or caesium 137, while electron beams are produced by high voltage accelerators. The experts considered the sources in four broad categories: large supervoltage units, intermediate units, small isotope units and units of electron beams or very high energy x-rays. Each group of source was described including its usage. The experts made it clear that while supervoltage radiation should be a part of an organized radiotherapy department, the radiation facilities at any particular establishment should not be of the supervoltage type alone. The high energy facilities could be fruitfully used only when there was a background of general radiotherapy. The group emphasized that supervoltage radiotherapy, in common with other forms of radiotherapy, should be conducted only by adequately trained and qualified personnel, including radiation physicists, and specified the training and qualifications required of such personnel. It was felt that specialized training was one of the main requirements at the present stage and the training programmes of IAEA and WHO should be utilized extensively for this

  20. High energy particle physics in the United Kingdom

    International Nuclear Information System (INIS)

    1985-06-01

    The paper reviews the U.K. participation in High Energy Particle Physics (HEPP) research. The funding of science in Higher Education and the Research Councils; high energy particle physics; relevance of particle physics to science and technology; particle physics in the U.K.; CERN; and the opportunity cost of HEPP within the science budget; are all discussed. (U.K.)

  1. Semiconductor high-energy radiation scintillation detector

    International Nuclear Information System (INIS)

    Kastalsky, A.; Luryi, S.; Spivak, B.

    2006-01-01

    We propose a new scintillation-type detector in which high-energy radiation generates electron-hole pairs in a direct-gap semiconductor material that subsequently recombine producing infrared light to be registered by a photo-detector. The key issue is how to make the semiconductor essentially transparent to its own infrared light, so that photons generated deep inside the semiconductor could reach its surface without tangible attenuation. We discuss two ways to accomplish this, one based on doping the semiconductor with shallow impurities of one polarity type, preferably donors, the other by heterostructure bandgap engineering. The proposed semiconductor scintillator combines the best properties of currently existing radiation detectors and can be used for both simple radiation monitoring, like a Geiger counter, and for high-resolution spectrography of the high-energy radiation. An important advantage of the proposed detector is its fast response time, about 1 ns, essentially limited only by the recombination time of minority carriers. Notably, the fast response comes without any degradation in brightness. When the scintillator is implemented in a qualified semiconductor material (such as InP or GaAs), the photo-detector and associated circuits can be epitaxially integrated on the scintillator slab and the structure can be stacked-up to achieve virtually any desired absorption capability

  2. New challenges in high-energy particle radiobiology

    Science.gov (United States)

    2014-01-01

    Densely ionizing radiation has always been a main topic in radiobiology. In fact, α-particles and neutrons are sources of radiation exposure for the general population and workers in nuclear power plants. More recently, high-energy protons and heavy ions attracted a large interest for two applications: hadrontherapy in oncology and space radiation protection in manned space missions. For many years, studies concentrated on measurements of the relative biological effectiveness (RBE) of the energetic particles for different end points, especially cell killing (for radiotherapy) and carcinogenesis (for late effects). Although more recently, it has been shown that densely ionizing radiation elicits signalling pathways quite distinct from those involved in the cell and tissue response to photons. The response of the microenvironment to charged particles is therefore under scrutiny, and both the damage in the target and non-target tissues are relevant. The role of individual susceptibility in therapy and risk is obviously a major topic in radiation research in general, and for ion radiobiology as well. Particle radiobiology is therefore now entering into a new phase, where beyond RBE, the tissue response is considered. These results may open new applications for both cancer therapy and protection in deep space. PMID:24198199

  3. Physics of intense, high energy radiation effects.

    Energy Technology Data Exchange (ETDEWEB)

    Hjalmarson, Harold Paul; Hartman, E. Frederick; Magyar, Rudolph J.; Crozier, Paul Stewart

    2011-02-01

    This document summarizes the work done in our three-year LDRD project titled 'Physics of Intense, High Energy Radiation Effects.' This LDRD is focused on electrical effects of ionizing radiation at high dose-rates. One major thrust throughout the project has been the radiation-induced conductivity (RIC) produced by the ionizing radiation. Another important consideration has been the electrical effect of dose-enhanced radiation. This transient effect can produce an electromagnetic pulse (EMP). The unifying theme of the project has been the dielectric function. This quantity contains much of the physics covered in this project. For example, the work on transient electrical effects in radiation-induced conductivity (RIC) has been a key focus for the work on the EMP effects. This physics in contained in the dielectric function, which can also be expressed as a conductivity. The transient defects created during a radiation event are also contained, in principle. The energy loss lead the hot electrons and holes is given by the stopping power of ionizing radiation. This information is given by the inverse dielectric function. Finally, the short time atomistic phenomena caused by ionizing radiation can also be considered to be contained within the dielectric function. During the LDRD, meetings about the work were held every week. These discussions involved theorists, experimentalists and engineers. These discussions branched out into the work done in other projects. For example, the work on EMP effects had influence on another project focused on such phenomena in gases. Furthermore, the physics of radiation detectors and radiation dosimeters was often discussed, and these discussions had impact on related projects. Some LDRD-related documents are now stored on a sharepoint site (https://sharepoint.sandia.gov/sites/LDRD-REMS/default.aspx). In the remainder of this document the work is described in catergories but there is much overlap between the atomistic

  4. Physics of intense, high energy radiation effects

    International Nuclear Information System (INIS)

    Hjalmarson, Harold Paul; Hartman, E. Frederick; Magyar, Rudolph J.; Crozier, Paul Stewart

    2011-01-01

    This document summarizes the work done in our three-year LDRD project titled 'Physics of Intense, High Energy Radiation Effects.' This LDRD is focused on electrical effects of ionizing radiation at high dose-rates. One major thrust throughout the project has been the radiation-induced conductivity (RIC) produced by the ionizing radiation. Another important consideration has been the electrical effect of dose-enhanced radiation. This transient effect can produce an electromagnetic pulse (EMP). The unifying theme of the project has been the dielectric function. This quantity contains much of the physics covered in this project. For example, the work on transient electrical effects in radiation-induced conductivity (RIC) has been a key focus for the work on the EMP effects. This physics in contained in the dielectric function, which can also be expressed as a conductivity. The transient defects created during a radiation event are also contained, in principle. The energy loss lead the hot electrons and holes is given by the stopping power of ionizing radiation. This information is given by the inverse dielectric function. Finally, the short time atomistic phenomena caused by ionizing radiation can also be considered to be contained within the dielectric function. During the LDRD, meetings about the work were held every week. These discussions involved theorists, experimentalists and engineers. These discussions branched out into the work done in other projects. For example, the work on EMP effects had influence on another project focused on such phenomena in gases. Furthermore, the physics of radiation detectors and radiation dosimeters was often discussed, and these discussions had impact on related projects. Some LDRD-related documents are now stored on a sharepoint site (https://sharepoint.sandia.gov/sites/LDRD-REMS/default.aspx). In the remainder of this document the work is described in catergories but there is much overlap between the atomistic calculations, the

  5. Studies In Theoretical High Energy Particle Physics

    Energy Technology Data Exchange (ETDEWEB)

    Keung, Wai Yee [Univ. of Illinois, Chicago, IL (United States)

    2017-07-01

    This is a final technical report for grant no. DE-SC0007948 describing research activities in theoretical high energy physics at University of Illinois at Chicago for the whole grant period from July 1, 2012 to March 31, 2017.

  6. Elementary particle physics and high energy phenomena

    International Nuclear Information System (INIS)

    Barker, A.R.; Cumalat, J.P.; de Alwis, S.P.; DeGrand, T.A.; Ford, W.T.; Mahanthappa, K.T.; Nauenberg, U.; Rankin, P.; Smith, J.G.

    1992-06-01

    This report discusses the following research in high energy physics: the properties of the z neutral boson with the SLD detector; the research and development program for the SDC muon detector; the fixed-target k-decay experiments; the Rocky Mountain Consortium for HEP; high energy photoproduction of states containing heavy quarks; and electron-positron physics with the CLEO II and Mark II detectors. (LSP)

  7. Elementary particle physics and high energy phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Barker, A.R.; Cumalat, J.P.; de Alwis, S.P.; DeGrand, T.A.; Ford, W.T.; Mahanthappa, K.T.; Nauenberg, U.; Rankin, P.; Smith, J.G.

    1992-06-01

    This report discusses the following research in high energy physics: the properties of the z neutral boson with the SLD detector; the research and development program for the SDC muon detector; the fixed-target k-decay experiments; the Rocky Mountain Consortium for HEP; high energy photoproduction of states containing heavy quarks; and electron-positron physics with the CLEO II and Mark II detectors. (LSP).

  8. Fluctuations in high-energy particle collisions

    International Nuclear Information System (INIS)

    Gronqvist, Hanna

    2016-01-01

    We study fluctuations that are omnipresent in high-energy particle collisions. These fluctuations can be either of either classical or quantum origin and we will study both. Firstly, we consider the type of quantum fluctuations that arise in proton-proton collisions. These are computable perturbatively in quantum field theory and we will focus on a specific class of diagrams in this set-up. Secondly, we will consider the fluctuations that are present in collisions between nuclei that can be heavier than protons. These are the quantum laws of nature that describe the positions of nucleons within a nucleus, but also the hydrodynamic fluctuations of classical, thermal origin that affect the evolution of the medium produced in heavy-ion collisions. The fluctuations arising in proton-proton collisions can be computed analytically up to a certain order in perturbative quantum field theory. We will focus on one-loop diagrams of a fixed topology. Loop diagrams give rise to integrals that typically are hard to evaluate. We show how modern mathematical methods can be used to ease their computation. We will study the relations among unitarity cuts of a diagram, the discontinuity across the corresponding branch cut and the coproduct. We show how the original integral corresponding to a given diagram can be reconstructed from the information contained in the coproduct. We expect that these methods can be applied to solve more complicated topologies and help in the computation of new amplitudes in the future. Finally, we study the two types of fluctuations arising in heavy-ion collisions. These are related either to the initial state or the intermediate state of matter produced in such collisions. The initial state fluctuations are experimentally observed to give rise to non-Gaussianities in the final-state spectra. We show how these non-Gaussianities can be explained by the random position and interaction energy of 'sources' in the colliding nuclei. Furthermore, we

  9. Elementary particle physics and high energy phenomena

    International Nuclear Information System (INIS)

    Barker, A.R.; Cumalat, J.P.; De Alwis, S.P.; DeGrand, T.A.; Ford, W.T.; Mahanthappa, K.T.; Nauenberg, U.; Rankin, P.; Smith, J.G.

    1992-06-01

    Experimental and theoretical high-energy physics programs at the University of Colorado are reported. Areas of concentration include the following: study of the properties of the Z 0 with the SLD detector; fixed-target K-decay experiments; the R ampersand D program for the muon system: the SDC detector; high-energy photoproduction of states containing heavy quarks; electron--positron physics with the CLEO II detector at CESR; lattice QCD; and spin models and dynamically triangulated random surfaces. 24 figs., 2 tabs., 117 refs

  10. Emulsion polymerization with high energy radiation

    International Nuclear Information System (INIS)

    Stannett, V.T.; Stahel, E.P.

    1992-01-01

    High energy radiation, particularly that of cobalt-60 or caesium-137 gamma-rays, provides in principle an ideal initiator for emulsion polymerization. The high free radical yields from the radiolysis of the aqueous phase combined with the high kinetic chain lengths associated with emulsion polymerization lead to a highly effective utilization of the radiation. There are other important advantages compared with the use of chemical initiators such as potassium persulfate. These are outlined in the chapter, together with some attendant disadvantages. Radiation-induced initiation is temperature independent, and low temperature polymerizations can be conducted with ease. Monomers that mainly terminate their growing chains by chain transfer to monomer give higher molecular weights at lower temperatures. Industrially, vinyl acetate is an important example of such a monomer, and it has been studied using radiation initiation. Both laboratory and pilot plant studies have been carried out and reported. The results are summarized in this chapter. Styrene is the classical example of a material that under a number of conditions closely obeys the so-called ideal Smith-Ewart kinetics. It has been found that under similar conditions but substituting radiation for potassium persulfate as the initiator, ideal kinetics were closely followed. Most of the conventional and some non-standard vinyl and diene monomers have been studied to some extent with radiation-initiated polymerizations in emulsion. To conserve space however, this chapter presents and discusses the results obtained only with styrene and vinyl acetate, both in laboratory and pilot plant investigations. Other monomers and special situations are referenced either directly or to the other available reviews. (orig.)

  11. Cryogenic Beam Screens for High-Energy Particle Accelerators

    CERN Document Server

    Baglin, V; Tavian, L; van Weelderen, R

    2013-01-01

    Applied superconductivity has become a key enabling technology for high-energy particle accelerators, thus making them large helium cryogenic systems operating at very low temperature. The circulation of high-intensity particle beams in these machines generates energy deposition in the first wall through different processes. For thermodynamic efficiency, it is advisable to intercept these beam-induced heat loads, which may be large in comparison with cryostat heat in-leaks, at higher temperature than that of the superconducting magnets of the accelerator, by means of beam screens located in the magnet apertures. Beam screens may also be used as part of the ultra-high vacuum system of the accelerator, by sheltering the gas molecules cryopumped on the beam pipe from impinging radiation and thus avoiding pressure runaway. Space being extremely tight in the magnet apertures, cooling of the long, slender beam screens also raises substantial problems in cryogenic heat transfer and fluid flow. We present sizing rule...

  12. Some problems of high-energy elementary particle physics

    International Nuclear Information System (INIS)

    Isaev, P.S.

    1995-01-01

    The problems of high-energy elementary particle physics are discussed. It is pointed out that the modern theory of elementary-particle physics has no solutions of some large physical problems: origin of the mass, electric charge, identity of particle masses, change of the mass of elementary particles in time and others. 7 refs

  13. High energy particle collisions near black holes

    Directory of Open Access Journals (Sweden)

    Zaslavskii O. B.

    2016-01-01

    Full Text Available If two geodesic particles collide near a rotating black hole, their energy in the centre of mass frame Ec.m. can become unbound under certain conditions (the so-called BSW effect. The special role is played here by so-called critical geodesics when one of particles has fine-tuned energy and angular momentum. The nature of geodesics reveals itself also in fate of the debris after collisions. One of particles moving to a remote observer is necessarily near-critical. We discuss, when such a collision can give rise not only unboud Ec.m. but also unbound Killing energy E (so-called super-Penrose process.

  14. The acceleration of particles to high energy

    International Nuclear Information System (INIS)

    Parker, E.N.

    1976-01-01

    The common occurrence, and often spectacular consequence, of fast particles in active astrophysical bodies has attracted the attention of physicists for more than four decades. The acceleration mechanisms, whatever they may be, are remarkably efficient, converting a major fraction of the total energy into fast particles. A variety of ideas have arisen, suggesting how and why fast particles are generated in various circumstances. The principal limitation on particle acceleration theories has been the realization that the universe in not filled with a hard vacuum, but rather is pervaded everywhere by tenuous ionized gases quite able to short circuit any large-scale electric fields that occur under ordinary circumstances. A number of the early ideas on the acceleration of cosmic rays have been discarded for this reason. The basic theoretical ideas can be grouped roughly into five parts: 1. hydromagnetic fields; 2. field in reduced conductivity; 3. plasma turbulence; 4. low frequency electromagnetic waves; 5. supernova explosion. Each of these is considered in turn. (Auth.)

  15. Nuclear reactions induced by high-energy alpha particles

    Science.gov (United States)

    Shen, B. S. P.

    1974-01-01

    Experimental and theoretical studies of nuclear reactions induced by high energy protons and heavier ions are included. Fundamental data needed in the shielding, dosimetry, and radiobiology of high energy particles produced by accelerators were generated, along with data on cosmic ray interaction with matter. The mechanism of high energy nucleon-nucleus reactions is also examined, especially for light target nuclei of mass number comparable to that of biological tissue.

  16. Cosmic gamma radiation of ultra high energy of primordial origin

    International Nuclear Information System (INIS)

    Aquino Filho, F.G. de.

    1984-01-01

    The quantum mechanical effects near a collapsing black hole as shown by Stephen W.Hawking in 1974 to produce streaming particles through tunneling effect was explored in the context of cosmic gamma ray production. In this thesis, we show the possible production of gamma rays of high energies (ν approx 10 41 Hz) in the initial stages of the formation of the Universe by the explosion of primordial mini black holes. These mini black hole explosions happening at 10 -43 s to 10 -37 s after the start perhaps may account for the existing universal cosmic background radiation of 2.7 0 K. (Author) [pt

  17. [High energy particle physics at Purdue, 1990--1991

    International Nuclear Information System (INIS)

    Gaidos, J.A.; Loeffler, F.J.; McIlwain, R.L.; Miller, D.H.; Palfrey, T.R.; Shibata, E.I.; Shipsey, I.P.

    1991-05-01

    Progress made in the experimental and theoretical high energy physics program is reviewed. The CLEO experiment, particle astrophysics, dynamical symmetry breaking in gauge theories, the Collider Detector at Fermilab, the TOPAZ Experiment, and elementary particle physics beyond the standard model are included

  18. A time of flight detector for high energy heavy particles

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Z; O` Connor, D J [Newcastle Univ., NSW (Australia). Dept. of Physics

    1994-12-31

    As a commonly used method to measure the energy of a particle with known mass, the flight time of the particle travelling over a certain distance is measured. A detector based on this principle is called a time-of-flight (TOF) detector which has attracted interests constantly during the last 15 years. For high energy heavy particle energy detection, TOF detector is an appropriated choice and such a system, developed recently, is described in this paper. 8 refs., 3 figs.

  19. A time of flight detector for high energy heavy particles

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Z.; O`Connor, D.J. [Newcastle Univ., NSW (Australia). Dept. of Physics

    1993-12-31

    As a commonly used method to measure the energy of a particle with known mass, the flight time of the particle travelling over a certain distance is measured. A detector based on this principle is called a time-of-flight (TOF) detector which has attracted interests constantly during the last 15 years. For high energy heavy particle energy detection, TOF detector is an appropriated choice and such a system, developed recently, is described in this paper. 8 refs., 3 figs.

  20. High energy particle experiment for the GEOTAIL mission

    International Nuclear Information System (INIS)

    1989-09-01

    The high energy particle experiment for GEOTAIL mission was designed to understand the particle acceleration mechanism, energy flow, boundary dynamics and magnetic reconnection mechanism in the geotail region, solar flare particle acceleration mechanism, the propagation mechanism through interplanetary space, and the origin, lifetime and propagation mechanism of cosmic ray heavy ions. In order to achieve these objectives, particle detectors, burst detectors, medium energy isotope telescopes and a high energy isotope telescope will be placed in the spacecraft which will be launched in 1992 as one of the spacecraft missions in the International Solar Terrestrial Physics program. With these detectors, electrons, protons and helium, carbon, silicon and iron particles will be detected. The characteristics and the main technique used for each instrument to observe high energy particles are summarized. The details of the scientific objectives, the basic principle of particle identification, the electronic system and data processing system, key parameter information, telemetry data formats, preflight and in-flight calibration method and data an analysis plan are described in this report. (K.I.)

  1. High-energy charged particle bursts in the near-Earth space as earthquake precursors

    Directory of Open Access Journals (Sweden)

    S. Yu. Aleksandrin

    2003-02-01

    Full Text Available The experimental data on high-energy charged particle fluxes, obtained in various near-Earth space experiments (MIR orbital station, METEOR-3, GAMMA and SAMPEX satellites were processed and analyzed with the goal to search for particle bursts. Particle bursts have been selected in every experiment considered. It was shown that the significant part of high-energy charged particle bursts correlates with seismic activity. Moreover, the particle bursts are observed several hours before strong earthquakes; L-shells of particle bursts and corresponding earthquakes are practically the same. Some features of a seismo-magnetosphere connection model, based on the interaction of electromagnetic emission of seismic origin and radiation belt particles, were considered. Key words. Ionospheric physics (energetic particles, trapped; energetic particles, precipitating; magnetosphere-ionosphere interactions

  2. Numerical evaluation of high energy particle effects in magnetohydrodynamics

    International Nuclear Information System (INIS)

    White, R.B.; Wu, Y.

    1994-03-01

    The interaction of high energy ions with magnetohydrodynamic modes is analyzed. A numerical code is developed which evaluates the contribution of the high energy particles to mode stability using orbit averaging of motion in either analytic or numerically generated equilibria through Hamiltonian guiding center equations. A dispersion relation is then used to evaluate the effect of the particles on the linear mode. Generic behavior of the solutions of the dispersion relation is discussed and dominant contributions of different components of the particle distribution function are identified. Numerical convergence of Monte-Carlo simulations is analyzed. The resulting code ORBIT provides an accurate means of comparing experimental results with the predictions of kinetic magnetohydrodynamics. The method can be extended to include self consistent modification of the particle orbits by the mode, and hence the full nonlinear dynamics of the coupled system

  3. Detection systems for high energy particle producing gaseous ionization

    International Nuclear Information System (INIS)

    Martinez, L.; Duran, I.

    1985-01-01

    This report contains a review on the most used detectors based on the collection of the ionization produced by high energy particles: proportional counters, multiwire proportional chambers, Geiger-Muller counters and drift chambers. In six sections, the fundamental principles, the field configuration and useful gas mixtures, are discussed, most relevant devices are reported along 90 pages with 98 references. (Author) 98 refs

  4. Detection systems for high energy particle producing gaseous ionization

    International Nuclear Information System (INIS)

    Duran, I.; Martinez, L.

    1985-01-01

    This report contains a review on the most used detectors based on the collection of the ionization produced by high energy particles: proportional counters, multiwire proportional chambers, Geiger-Mueller counters and drift chambers. In six sections, the fundamental principles, the field configuration and useful gas mixtures are discussed, most relevant devices are reported. (author)

  5. Azimuthal asymmetry of slow particles in high energy nuclear interaction

    International Nuclear Information System (INIS)

    Sarkar, Subir; Goswami, T.D.

    2002-01-01

    An asymmetry in the angular distribution of slow particles in the azimuthal plane has been observed during high energy nuclear disintegration of photo emulsion nuclei exposed to 1.8 GeV/c k - and 20 GeV/c protons. The mechanism of disintegration is not in accordance with the cascade-evaporation model, which is based on isotropic emission of slow particles. Deviation from isotropy indicates that some of the slow particles might be emitted well before the thermal equilibrium is reached in the disintegrating system. (author)

  6. [Studies of elementary particles and high energy phenomena: [Progress report

    International Nuclear Information System (INIS)

    Cumalat, J.P.

    1989-01-01

    The scope of work under this contract is unclassified and shall consist of experimental, theoretical, and phenomenological research on the fundamental properties of high energy subnuclear particles at the Fermi National Accelerator Laboratory, the Stanford Linear Accelerator Center, the Los Alamos National Laboratory, the SSC laboratory, and the University of Colorado with emphasis on photon beam experiments, electron-positron interactions, charmed particles, production of new vector bosons, advanced data acquisition systems, two photon physics, particle lifetimes, supergravity, supersymmetry, superstrings, quantum chromodynamics, nonequilibrium statistical mechanics, cosmology, phase transitions, lattice gauge theory, anomaly-free theories, gravity and instrumentation development. These topics are covered in this report

  7. High energy behaviour of particles and unified statistics

    International Nuclear Information System (INIS)

    Chang, Y.

    1984-01-01

    Theories and experiments suggest that particles at high energy appear to possess a new statistics unifying Bose-Einstein and Fermi-Dirac statistics via the GAMMA distribution. This hypothesis can be obtained from many models, and agrees quantitatively with scaling, the multiplicty, large transverse momentum, the mass spectrum, and other data. It may be applied to scatterings at high energy, and agrees with experiments and known QED's results. The Veneziano model and other theories have implied new statistics, such as, the B distribution and the Polya distribution. They revert to the GAMMA distribution at high energy. The possible inapplicability of Pauli's exclusion principle within the unified statistics is considered and associated to the quark constituents

  8. Laser focusing of high-energy charged-particle beams

    International Nuclear Information System (INIS)

    Channell, P.J.

    1986-01-01

    It is shown that laser focusing of high-energy charged-particle beams using the inverse Cherenkov effect is well suited for applications with large linear colliders. Very high gradient (>0.5 MG/cm) lenses result that can be added sequentially without AG cancellation. These lenses are swell understood, have small geometric aberrations, and offer the possibility of correlating phase and energy aberrations to produce an achromatic final focus

  9. Neutrino fluxes produced by high energy solar flare particles

    International Nuclear Information System (INIS)

    Kolomeets, E.V.; Shmonin, V.L.

    1975-01-01

    In this work the calculated differential energy spectra of neutrinos poduced by high energy protons accelerated during 'small' solar flares are presented. The muon flux produced by neutrino interactions with the matter at large depths under the ground is calculated. The obtained flux of muons for the total number of solar flare accelerated protons of 10 28 - 10 32 is within 10 9 - 10 13 particles/cm 2 X s x ster. (orig.) [de

  10. Plasma focusing and diagnosis of high energy particle beams

    International Nuclear Information System (INIS)

    Chen, Pisin.

    1990-09-01

    Various novel concepts of focusing and diagnosis of high energy charged particle beams, based on the interaction between the relativistic particle beam and the plasma, are reviewed. This includes overdense thin plasma lenses, and (underdense) adiabatic plasma lens, and two beam size monitor concepts. In addition, we introduce another mechanism for measuring flat beams based on the impulse received by heavy ions in an underdense plasma. Theoretical investigations show promise of focusing and diagnosing beams down to sizes where conventional methods are not possible to provide. 21 refs

  11. Broken flavor symmetries in high energy particle phenomenology

    International Nuclear Information System (INIS)

    Antaramian, A.

    1995-01-01

    Over the past couple of decades, the Standard Model of high energy particle physics has clearly established itself as an invaluable tool in the analysis of high energy particle phenomenon. However, from a field theorists point of view, there are many dissatisfying aspects to the model. One of these, is the large number of free parameters in the theory arising from the Yukawa couplings of the Higgs doublet. In this thesis, we examine various issues relating to the Yukawa coupeng structure of high energy particle field theories. We begin by examining extensions to the Standard Model of particle physics which contain additional scalar fields. By appealing to the flavor structure observed in the fermion mass and Kobayashi-Maskawa matrices, we propose a reasonable phenomenological parameterization of the new Yukawa couplings based on the concept of approximate flavor symmetries. It is shown that such a parameterization eliminates the need for discrete symmetries which limit the allowed couplings of the new scalars. New scalar particles which can mediate exotic flavor changing reactions can have masses as low as the weak scale. Next, we turn to the issue of neutrino mass matrices, where we examine a particular texture which leads to matter independent neutrino oscillation results for solar neutrinos. We, then, examine the basis for extremely strict limits placed on flavor changing interactions which also break lepton- and/or baryon-number. These limits are derived from cosmological considerations. Finally, we embark on an extended analysis of proton decay in supersymmetric SO(10) grand unified theories. In such theories, the dominant decay diagrams involve the Yukawa couplings of a heavy triplet superfield. We argue that past calculations of proton decay which were based on the minimal supersymmetric SU(5) model require reexamination because the Yukawa couplings of that theory are known to be wrong

  12. Compilation of radiation damage test data part III: materials used around high-energy accelerators

    CERN Document Server

    Beynel, P; Schönbacher, H; CERN. Geneva

    1982-01-01

    For pt.II see CERN report 79-08 (1979). This handbook gives the results of radiation damage tests on various engineering materials and components intended for installation in radiation areas of the CERN high-energy particle accelerators. It complements two previous volumes covering organic cable-insulating materials and thermoplastic and thermosetting resins.

  13. Radiation protection of the operation of accelerator facilities. On high energy proton and electron accelerators

    International Nuclear Information System (INIS)

    Kondo, Kenjiro

    1997-01-01

    Problems in the radiation protection raised by accelerated particles with energy higher than several hundreds MeV in strong accelerator facilities were discussed in comparison with those with lower energy in middle- and small-scale facilities. The characteristics in the protection in such strong accelerator facilities are derived from the qualitative changes in the interaction between the high energy particles and materials and from quantitative one due to the beam strength. In the former which is dependent on the emitting mechanism of the radiation, neutron with broad energy spectrum and muon are important in the protection, and in the latter, levels of radiation and radioactivity which are proportional to the beam strength are important. The author described details of the interaction between high energy particles and materials: leading to the conclusion that in the electron accelerator facilities, shielding against high energy-blemsstrahlung radiation and -neutron is important and in the proton acceleration, shielding against neutron is important. The characteristics of the radiation field in the strong accelerator facilities: among neutron, ionized particles and electromagnetic wave, neutron is most important in shielding since it has small cross sections relative to other two. Considerations for neutron are necessary in the management of exposure. Multiplicity of radionuclides produced: which is a result of nuclear spallation reaction due to high energy particles, especially to proton. Radioactivation of the accelerator equipment is a serious problem. Other problems: the interlock systems, radiation protection for experimenters and maintenance of the equipment by remote systems. (K.H.). 11 refs

  14. High energy particle transport code NMTC/JAM

    International Nuclear Information System (INIS)

    Niita, K.; Takada, H.; Meigo, S.; Ikeda, Y.

    2001-01-01

    We have developed a high energy particle transport code NMTC/JAM, which is an upgrade version of NMTC/JAERI97. The available energy range of NMTC/JAM is, in principle, extended to 200 GeV for nucleons and mesons including the high energy nuclear reaction code JAM for the intra-nuclear cascade part. We compare the calculations by NMTC/JAM code with the experimental data of thin and thick targets for proton induced reactions up to several 10 GeV. The results of NMTC/JAM code show excellent agreement with the experimental data. From these code validation, it is concluded that NMTC/JAM is reliable in neutronics optimization study of the high intense spallation neutron utilization facility. (author)

  15. Recipients of 2013 EPS High Energy & Particle Physics Prize

    CERN Multimedia

    ATLAS, Experiment

    2014-01-01

    (From left) Joe Incandela, Peter Higgs, Francois Englert, Tejinder Virdee, Dave Charlton, and Peter Jenni. Higgs and Englert gave the prizes to the recipients of the 2013 European Physical Society's High Energy and Particle Physics Prize, for an outstanding contribution to high energy physics. "For the discovery of a Higgs boson, as predicted by the Brout-Englert-Higgs mechanism," the prize was awarded to the ATLAS and CMS collaborations. Spokesperson for CMS, Incandela, and Spokesperson for ATLAS, Charlton, accepted the awards on their collaborations' behalf. "For their pioneering and outstanding leadership roles in the making of the ATLAS and CMS experiments," the prize was awarded to Jenni, Virdee, and Michel Della Negra (not present). Image: ATLAS

  16. High-energy tail distributions and resonant wave particle interaction

    Science.gov (United States)

    Leubner, M. P.

    1983-01-01

    High-energy tail distributions (k distributions) are used as an alternative to a bi-Lorentzian distribution to study the influence of energetic protons on the right- and left-hand cyclotron modes in a hot two-temperature plasma. Although the parameters are chosen to be in a range appropriate to solar wind or magnetospheric configurations, the results apply not only to specific space plasmas. The presence of energetic particles significantly alters the behavior of the electromagnetic ion cyclotron modes, leading to a wide range of unstable frequencies and increased growth rates. From the strongly enhanced growth rates it can be concluded that high-energy tail distributions should not show major temperature anisotropies, which is consistent with observations.

  17. High-energy particles associated with solar flares

    International Nuclear Information System (INIS)

    Sakurai, K.; Klimas, A.J.

    1974-05-01

    High energy particles, the so-called solar cosmic rays, are often generated in association with solar flares, and then emitted into interplanetary space. These particles, consisting of electrons, protons, and other heavier nuclei, including the iron-group, are accelerated in the vicinity of the flare. By studying the temporal and spatial variation of these particles near the earth's orbit, their storage and release mechanisms in the solar corona and their propagation mechanism can be understood. The details of the nuclear composition and the rigidity spectrum for each nuclear component of the solar cosmic rays are important for investigating the acceleration mechanism in solar flares. The timing and efficiency of the acceleration process can also be investigated by using this information. These problems are described in some detail by using observational results on solar cosmic rays and associated phenomena. (U.S.)

  18. Estimation of the R134a gas refractive index for use as a Cherenkov radiator, using a high energy charged particle beam

    Science.gov (United States)

    Charitonidis, N.; Karyotakis, Y.; Gatignon, L.

    2017-11-01

    Gases with relatively high refractive index, n - 1 ≥ 500 ×10-6 at atmospheric pressure, giving a satisfactory photoelectron yield at relatively low pressures (≤ 5 bar) are rare. These gases are often the only practical solution for low momentum particle identification in conventional secondary beam lines. The refractive index of R134a, one of the most common gases available to the physics community, has never been measured or reported. In the present note, the results of a dedicated experiment to estimate the refractive index of R134a, using mixed hadron/electron beams in the range 0.5-10 GeV are presented.

  19. Performance of paint coatings in the radiation fields of nuclear reactors and of high energy particle accelerators and after contamination by radionuclides

    CERN Document Server

    Schönbacher, Helmut; Oesterle, K M; Van de Voorde, M

    1977-01-01

    Several commercially available two/component coating systems based on epoxy and polyurethane resin, as well as lithium silicate/zinc dust paint coatings, have been irradiated in a nuclear reactor up to a dose of 2*10/sup 9/ rad and in a 28 GeV proton accelerator up to a dose of 1*10/sup 9/ rad. Besides assessment by visual inspection, the irradiated specimens have been subjected to the impact hardness test, the infinitesimal hardness behaviour tests, the grid scarification test and to swelling tests in methanol and acetone. The decontaminability of these paint coatings after contamination with solutions containing Ca 45, S 35 and I 131 is also investigated. Very good results in respect of decontaminability and radiation resistance up to 1*10/sup 9/ rad have been obtained with a coating of polyurethane cross-linked with an aliphatic diisocyanate. (9 refs).

  20. Elementary particles and high energy phenomena: Progress report

    International Nuclear Information System (INIS)

    Cumalat, J.P.

    1988-01-01

    This paper reviews the research being done at the University of Colorado in High Energy Physics. Topics discussed in this paper are: Charmed Photoproduction; Hadronic Production of Charm Particles; Photoproduction of States Containing Heavy Quarks; Electron-Positron Physics with the MAC Detector at PEP; Electron-Positron Physics with the Upgraded Mark II Detector at SLC; The SLD Detector at SLC; Nonperturbative Studies of QCD; Hadron Phenomenology - Application to Experiment; Perturbative QCD and Weak Matrix Elements; Quarkonium Physics; Supersymmetry, Supergravity, and Superstrings; and Experimental Gravity. 50 refs., 13 figs

  1. Challenge of high energy radiation dosimetry and protection

    International Nuclear Information System (INIS)

    Nelson, W.R.; Jenkins, T.M.

    1976-08-01

    An accelerator health physicist can make contributions in many fields of science in addition to the various operational tasks that he is charged with. He can support others in his laboratory by designing shielding for new accelerators and storage rings, by consulting with experimenters on background radiation problems that they may encounter, by helping the high energy physicist select appropriate radiation sources for checking out his equipment, by providing him with low energy atomic and nuclear physics calculations, and many other ways. Most of all, he can perform and publish research using the many tools and techniques that are at his disposal at a high-energy accelerator laboratory

  2. Electronic Instrumentations for High Energy Particle Physics and Neutrino Physics

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00452332

    The present dissertation describes design, qualification and operation of several electronic instrumentations for High Energy Particle Physics experiments (LHCb) and Neutrino Physics experiments (CUORE and CUPID). Starting from 2019, the LHCb experiment at the LHC accelerator will be upgraded to operate at higher luminosity and several of its detectors will be redesigned. The RICH detector will require a completely new optoelectronic readout system. The development of such system has already reached an advanced phase, and several tests at particle beam facilities allowed to qualify the performance of the entire system. In order to achieve a higher stability and a better power supply regulation for the front-end chip, a rad-hard low dropout linear regulator, named ALDO, has been developed. Design strategies, performance tests and results from the irradiation campaign are presented. In the Neutrino Physics field, large-scale bolometric detectors, like those adopted by CUORE and its future upgrade CUPID, offer u...

  3. High energy particle transport code NMTC/JAM

    International Nuclear Information System (INIS)

    Niita, Koji; Meigo, Shin-ichiro; Takada, Hiroshi; Ikeda, Yujiro

    2001-03-01

    We have developed a high energy particle transport code NMTC/JAM, which is an upgraded version of NMTC/JAERI97. The applicable energy range of NMTC/JAM is extended in principle up to 200 GeV for nucleons and mesons by introducing the high energy nuclear reaction code JAM for the intra-nuclear cascade part. For the evaporation and fission process, we have also implemented a new model, GEM, by which the light nucleus production from the excited residual nucleus can be described. According to the extension of the applicable energy, we have upgraded the nucleon-nucleus non-elastic, elastic and differential elastic cross section data by employing new systematics. In addition, the particle transport in a magnetic field has been implemented for the beam transport calculations. In this upgrade, some new tally functions are added and the format of input of data has been improved very much in a user friendly manner. Due to the implementation of these new calculation functions and utilities, consequently, NMTC/JAM enables us to carry out reliable neutronics study of a large scale target system with complex geometry more accurately and easily than before. This report serves as a user manual of the code. (author)

  4. IceCube: Particle Astrophysics with High Energy Neutrinos

    CERN Multimedia

    Université de Genève

    2012-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92 Monday 7 May 2012 17h. - Ecole de Physique, Auditoire Stueckelberg IceCube: Particle Astrophysics with High Energy Neutrinos Prof. Francis Halzen / University of Wisconsin, Madison Construction and commissioning of the cubic-kilometer IceCube neutrino detector and its low energy extension DeepCore have been completed. The instrument detects neutrinos over a wide energy range: from 10 GeV atmospheric neutrinos to 1010 GeV cosmogenic neutrinos. We will discuss initial results based on a subsample of the ~100,000 neutrino events recorded during construction. We will emphasize the first measurement of the high-energy atmospheric neutrino spectrum, the search for the still enigmatic sources of the Galactic and extragalactic cosmic rays and for the particle nature of dark matter. Une ve...

  5. High energy radiation from black holes gamma rays, cosmic rays, and neutrinos

    CERN Document Server

    Dermer, Charles D

    2009-01-01

    Bright gamma-ray flares observed from sources far beyond our Milky Way Galaxy are best explained if enormous amounts of energy are liberated by black holes. The highest- energy particles in nature--the ultra-high-energy cosmic rays--cannot be confined by the Milky Way's magnetic field, and must originate from sources outside our Galaxy. Understanding these energetic radiations requires an extensive theoretical framework involving the radiation physics and strong-field gravity of black holes. In High Energy Radiation from Black Holes, Charles Dermer and Govind Menon present a systemat

  6. System for determining absorbed dose and its distribution for high-energy electron radiation

    International Nuclear Information System (INIS)

    Hegewald, H.; Wulff, W.

    1977-01-01

    Taking into account the polarization effect, the dose determination for high-energy electron radiation from particle accelerators depends on the knowledge of the energy dependence of the mass stopping power. Results obtained with thermoluminescent dosemeters agree with theoretical values. For absorbed dose measurements the primary energy of electron radiation has been determined by nuclear photoreactions, and the calculation of the absorbed dose from charge measurements by means of the mass stopping power is described. Thus the calibration of ionization chambers for high-energy electron radiation by absolute measurements with the Faraday cage and chemical dosemeters has become possible. (author)

  7. Radiation effects on integrated circuits used in high energy research

    International Nuclear Information System (INIS)

    Kanofsky, A.S.; Yost, B.; Farr, W.

    1990-01-01

    The authors report here on radiation effects on two amplifiers used in high energy experiments. These are standard devices that are produced by LeCroy. They describe each of the devices and the experimental techniques. Finally, they present and discuss the results of the measurements. 5 figs

  8. High energy electromagnetic particle transportation on the GPU

    Energy Technology Data Exchange (ETDEWEB)

    Canal, P. [Fermilab; Elvira, D. [Fermilab; Jun, S. Y. [Fermilab; Kowalkowski, J. [Fermilab; Paterno, M. [Fermilab; Apostolakis, J. [CERN

    2014-01-01

    We present massively parallel high energy electromagnetic particle transportation through a finely segmented detector on a Graphics Processing Unit (GPU). Simulating events of energetic particle decay in a general-purpose high energy physics (HEP) detector requires intensive computing resources, due to the complexity of the geometry as well as physics processes applied to particles copiously produced by primary collisions and secondary interactions. The recent advent of hardware architectures of many-core or accelerated processors provides the variety of concurrent programming models applicable not only for the high performance parallel computing, but also for the conventional computing intensive application such as the HEP detector simulation. The components of our prototype are a transportation process under a non-uniform magnetic field, geometry navigation with a set of solid shapes and materials, electromagnetic physics processes for electrons and photons, and an interface to a framework that dispatches bundles of tracks in a highly vectorized manner optimizing for spatial locality and throughput. Core algorithms and methods are excerpted from the Geant4 toolkit, and are modified and optimized for the GPU application. Program kernels written in C/C++ are designed to be compatible with CUDA and OpenCL and with the aim to be generic enough for easy porting to future programming models and hardware architectures. To improve throughput by overlapping data transfers with kernel execution, multiple CUDA streams are used. Issues with floating point accuracy, random numbers generation, data structure, kernel divergences and register spills are also considered. Performance evaluation for the relative speedup compared to the corresponding sequential execution on CPU is presented as well.

  9. High energy radiation effects on the human body

    International Nuclear Information System (INIS)

    Kato, Kazuaki

    1977-01-01

    High-energy radiation injuries and their risks were recognized, information on low-energy radiation injuries was also arranged, and with these backgrounds, countermeasures against prevention of radiation injuries were considered. Redintegration of DNA and mutation by radiation were described, and relationship between radiation injuries and dose was considered. Interaction of high-energy radiation and substances in the living body and injuries by the interaction were also considered. Expression method of risk was considered, and a concept of protection dose was suggested. Protection dose is dose equivalent which is worthy of value at the point where the ratio to permissible dose distributed among each part of the body is at its maximum in the distribution of dose equivalent formed within the body when standard human body is placed at a certain radiation field for a certain time. Significance and countermeasures of health examination which is under an abligation to make radiation workers receive health check were thought, and problems were proposed on compensation when radiation injuries should appear actually. (Tsunoda, M.)

  10. Relevance of axionlike particles for very-high-energy astrophysics

    International Nuclear Information System (INIS)

    De Angelis, Alessandro; Galanti, Giorgio; Roncadelli, Marco

    2011-01-01

    Several extensions of the standard model and, in particular, superstring theories suggest the existence of axionlike particles (ALPs), which are very light spin-zero bosons with a two-photon coupling. As a consequence, photon-ALP oscillations occur in the presence of an external magnetic field, and ALPs can lead to observable effects on the measured photon spectrum of astrophysical sources. An intriguing situation arises when blazars are observed in the very-high-energy (VHE) band--namely, above 100 GeV--as it is the case with the presently operating Imaging Atmospheric Cherenkov Telescopes H.E.S.S, Major Atmospheric Gamma Imaging Cherenkov telescope, Collaboration of Australia and Nippon for a Gamma Ray Observatory in the Outback III, and VERITAS. The extragalactic background light produced by galaxies during cosmic evolution gives rise to a source dimming which becomes important in the VHE band and increases with energy, since hard photons from a blazar scatter off soft extragalactic background light photons thereby disappearing into e + e - pairs. This dimming can be considerably reduced by photon-ALP oscillations, and since they are energy independent the resulting blazar spectra become harder than expected. We consider throughout a scenario first proposed by De Angelis, Roncadelli, and Mansutti in which the above strategy is implemented with photon-ALP oscillations triggered by large-scale magnetic fields, and we systematically investigate its implications for VHE blazars. We find that for ALPs lighter than 5·10 -10 eV the photon survival probability is larger than predicted by conventional physics above a few hundred GeV. Specifically, a boost factor of 10 can easily occur for sources at large distance and large energy, e.g. at 8 TeV for the blazar 1ES 0347-121 at redshift z=0.188. This is a clear-cut prediction which can be tested with the planned Cherenkov Telescope Array and the High Altitude Water Cherenkov Experiment (HAWC) water Cherenkov

  11. [High energy particle physics at Purdue, 1989--1990

    International Nuclear Information System (INIS)

    Gaidos, J.A.; Loeffler, F.J.; McIlwain, R.L.; Miller, D.H.; Palfrey, T.R.; Shibata, E.I.; Shipsey, I.P.

    1990-05-01

    The theoretical and experimental high energy physics program is reviewed, including developments on particle detectors. Among the topics addressed are the following: the CLEO experiment; gamma ray astrophysics; highest-weight representations of affine Kac-Moody algebras; supersymmetric field theories; parity- violating effects and superconductivity in 2 + 1 dimensional supersymmetric QED; neutrino oscillations with applications to solar and supernova neutrinos; a search for the quark-gluon plasma using the Fermilab collider; the Solenoid Detector Collaboration at SSC; the high-resolution vertex chamber at TRISTAN; CP violation in e + e - →φ→K L K S ; deviations from Coulomb's Law; and the electric charge and equations of state of neutron stars

  12. Investigation of Rare Particle Production in High Energy Nuclear Collisions

    International Nuclear Information System (INIS)

    Crawford, Henry J.; Engelage, Jon M.

    1999-01-01

    Our program is an investigation of the hadronization process through measurement of rare particle production in high energy nuclear interactions. Such collisions of heavy nuclei provide an environment similar in energy density to the conditions in the Big Bang. We are currently involved in two major experiments to study this environment, E896 at the AGS and STAR at RHIC. We have completed our physics running of E896, a search for the H dibaryon and measurement of hyperon production in AuAu collisions, and are in the process of analyzing the data. We have produced the electronics and software for the STAR trigger and will begin to use these tools to search for anti-nuclei and strange hadrons when RHIC turns on later this year

  13. High-Energy Solar Particle Events in Cycle 24

    Science.gov (United States)

    Gopalswamy, N.; Makela, P.; Yashiro, S.; Xie, H.; Akiyama, S.; Thakur, N.

    2015-01-01

    The Sun is already in the declining phase of cycle 24, but the paucity of high-energy solar energetic particle (SEP) events continues with only two ground level enhancement (GLE) events as of March 31, 2015. In an attempt to understand this, we considered all the large SEP events of cycle 24 that occurred until the end of 2014. We compared the properties of the associated CMEs with those in cycle 23. We found that the CME speeds in the sky plane were similar, but almost all those cycle-24 CMEs were halos. A significant fraction of (16%) of the frontside SEP events were associated with eruptive prominence events. CMEs associated with filament eruption events accelerate slowly and attain peak speeds beyond the typical GLE release heights. When we considered only western hemispheric events that had good connectivity to the CME nose, there were only 8 events that could be considered as GLE candidates. One turned out to be the first GLE event of cycle 24 (2012 May 17). In two events, the CMEs were very fast (>2000 km/s) but they were launched into a tenuous medium (high Alfven speed). In the remaining five events, the speeds were well below the typical GLE CME speed (2000 km/s). Furthermore, the CMEs attained their peak speeds beyond the typical heights where GLE particles are released. We conclude that several factors contribute to the low rate of high-energy SEP events in cycle 24: (i) reduced efficiency of shock acceleration (weak heliospheric magnetic field), (ii) poor latitudinal and longitudinal connectivity), and (iii) variation in local ambient conditions (e.g., high Alfven speed).

  14. Practical aspects of shielding high-energy particle accelerators

    International Nuclear Information System (INIS)

    Thomas, R.H.; Univ. of California, Berkeley, CA

    1993-09-01

    The experimental basis of shielding design for high-energy accelerators that has been established over the past thirty years is described. Particular emphasis is given to the design of large accelerators constructed underground. The first data obtained from cosmic-ray physics were supplemented by basic nuclear physics. When these data proved insufficient, experiments were carried out and interpreted by several empirical formulae -- the most successful of which has been the Moyer Model. This empirical model has been used successfully to design the shields of most synchrotrons currently in operation, and is still being used in preliminary design and to check the results of neutron transport calculations. Accurate shield designs are needed to reduce external radiation levels during accelerator operations and to minimize environmental impacts such as open-quotes skyshineclose quotes and the production of radioactivity in groundwater. Examples of the cost of minimizing such environmental impacts are given

  15. Detectors for Particle Radiation

    Science.gov (United States)

    Kleinknecht, Konrad

    1999-01-01

    This textbook provides a clear, concise and comprehensive review of the physical principles behind the devices used to detect charged particles and gamma rays, and the construction and performance of these many different types of detectors. Detectors for high-energy particles and radiation are used in many areas of science, especially particle physics and nuclear physics experiments, nuclear medicine, cosmic ray measurements, space sciences and geological exploration. This second edition includes all the latest developments in detector technology, including several new chapters covering micro-strip gas chambers, silicion strip detectors and CCDs, scintillating fibers, shower detectors using noble liquid gases, and compensating calorimeters for hadronic showers. This well-illustrated textbook contains examples from the many areas in science in which these detectors are used. It provides both a coursebook for students in physics, and a useful introduction for researchers in other fields.

  16. Evaluation of fluence to dose equivalent conversion factors for high energy radiations, (1)

    International Nuclear Information System (INIS)

    Sato, Osamu; Uehara, Takashi; Yoshizawa, Nobuaki; Iwai, Satoshi; Tanaka, Shun-ichi.

    1992-09-01

    Computer code system and basic data have been investigated for evaluating fluence to dose equivalent conversion factors for photons and neutrons up to 10 GeV. The present work suggested that the conversion factors would be obtained by incorporating effective quality factors of charged particles into the HERMES (High Energy Radiation Monte Carlo Elaborate System) code system. The effective quality factors for charged particles were calculated on the basis of the Q-L relationships specified in the ICRP Publication-60. (author)

  17. High Energy Ion Acceleration by Extreme Laser Radiation Pressure

    Science.gov (United States)

    2017-03-14

    published in the internationally leading journal Physical Review Letters. We continued to progress this pionee 15.  SUBJECT TERMS ion therapy, heavy ion ...Thomson parabola spectrometer: To separate and provide a measurement of the charge -to-mass ratio and energy spectrum of the different ion species...AFRL-AFOSR-UK-TR-2017-0015 High energy ion acceleration by extreme laser radiation pressure Paul McKenna UNIVERSITY OF STRATHCLYDE VIZ ROYAL COLLEGE

  18. PREFACE: High Energy Particle Physics Workshop (HEPPW2015)

    Science.gov (United States)

    Cornell, Alan S.; Mellado, B.

    2015-10-01

    The motivation for this workshop began with the discovery of the Higgs boson three years ago, and the realisation that many problems remain in particle physics, such as why there is more matter than anti-matter, better determining the still poorly measured parameters of the strong force, explaining possible sources for dark matter, naturalness etc. While the newly discovered Higgs boson seems to be compatible with the Standard Model, current experimental accuracy is far from providing a definitive statement with regards to the nature of this new particle. There is a lot of room for physics beyond the Standard Model to emerge in the exploration of the Higgs boson. Recent measurements in high-energy heavy ion collisions at the LHC have shed light on the complex dynamics that govern high-density quark-gluon interactions. An array of results from the ALICE collaboration have been highlighted in a recent issue of CERN courier. The physics program of high-energy heavy ion collisions promises to further unveil the intricacies of high-density quark-gluon plasma physics. The great topicality of high energy physics research has also seen a rapid increase in the number of researchers in South Africa pursuing such studies, both experimentally through the ATLAS and ALICE colliders at CERN, and theoretically. Young researchers and graduate students largely populate these research groups, with little experience in presenting their work, and few support structures (to their knowledge) to share experiences with. Whilst many schools and workshops have sought to educate these students on the theories and tools they will need to pursue their research, few have provided them with a platform to present their work. As such, this workshop discussed the various projects being pursued by graduate students and young researchers in South Africa, enabling them to develop networks for future collaboration and discussion. The workshop took place at the iThemba Laboratories - North facility, in

  19. High-energy outer radiation belt dynamic modeling

    International Nuclear Information System (INIS)

    Chiu, Y.T.; Nightingale, R.W.; Rinaldi, M.A.

    1989-01-01

    Specification of the average high-energy radiation belt environment in terms of phenomenological montages of satellite measurements has been available for some time. However, for many reasons both scientific and applicational (including concerns for a better understanding of the high-energy radiatino background in space), it is desirable to model the dynamic response of the high-energy radiation belts to sources, to losses, and to geomagnetic activity. Indeed, in the outer electron belt, this is the only mode of modeling that can handle the large intensity fluctuations. Anticipating the dynamic modeling objective of the upcoming Combined Release and Radiation Effects Satellite (CRRES) program, we have undertaken to initiate the study of the various essential elements in constructing a dynamic radiation belt model based on interpretation of satellite data according to simultaneous radial and pitch-angle diffusion theory. In order to prepare for the dynamic radiation belt modeling based on a large data set spanning a relatively large segment of L-values, such as required for CRRES, it is important to study a number of test cases with data of similar characteristics but more restricted in space-time coverage. In this way, models of increasing comprehensiveness can be built up from the experience of elucidating the dynamics of more restrictive data sets. The principal objectives of this paper are to discuss issues concerning dynamic modeling in general and to summarize in particular the good results of an initial attempt at constructing the dynamics of the outer electron radiation belt based on a moderately active data period from Lockheed's SC-3 instrument flown on board the SCATHA (P78-2) spacecraft. Further, we shall discuss the issues brought out and lessons learned in this test case

  20. Radiation-hard silicon photonics for high energy physics and beyond

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    Silicon photonics (SiPh) is currently being investigated as a promising technology for future radiation hard optical links. The possibility of integrating SiPh devices with electronics and/or silicon particle sensors as well as an expected very high resistance against radiation damage make this technology particularly interesting for potential use close to the interaction points in future in high energy physics experiments and other radiation-sensitive applications. The presentation will summarize the outcomes of the research on radiation hard SiPh conducted within the ICE-DIP projected.

  1. Radiation collimator for use with high energy radiation beams

    International Nuclear Information System (INIS)

    Malak, S.P.

    1978-01-01

    A collimator is described for use with a beam of radiation, and in particular, for use in controlling the cross-sectional size and shape of the radiation beam and intercepting undesired off-focus radiation in an x-ray apparatus. The collimator is positioned adjacent to the source of radiation and embodies a plurality longitudinally extending leaves pivotally mounted on and between two supports, the leaves move about their pivots to close overlapping relation to define a hollow cone. The cone defines an aperture at its narrow end which can be adjusted in size and shape by rotation of the two supports which are adaptable to being moved one relative to the other, to cause an expansion or contraction of the hollow cone and correspondingly an increase or decrease of the cross-sectional size and/or shape of the radiation beam passing through the aperture

  2. High energy particles from {gamma}-ray bursts

    Energy Technology Data Exchange (ETDEWEB)

    Waxman, E [Weizmann Institute of Science, Rehovot (Israel)

    2001-11-15

    A review is presented of the fireball model of {gamma}-ray bursts (GRBs), and of the production in GRB fireballs of high energy protons and neutrinos. Constraints imposed on the model by recent afterglow observations, which support the association of GRB and ultra-high energy cosmic-ray (UHECR) sources, are discussed. Predictions of the GRB model for UHECR production, which can be tested with planned large area UHECR detectors and with planned high energy neutrino telescopes, are reviewed. (author)

  3. Radiation processing with high-energy X-rays

    International Nuclear Information System (INIS)

    Cleland, Marshall R.; Stichelbaut, Frederic

    2009-01-01

    The physical, chemical or biological characteristics of selected commercial products and materials can be improved by radiation processing. The ionizing energy can be provided by accelerated electrons with energies between 75 keV and 10 MeV, gamma rays from cobalt-60 with average energies of 1.25 MeV or X-rays with maximum energies up to 7.5 MeV. Electron beams are preferred for thin products, which are processed at high speeds. Gamma rays are used for products that are too thick for treatment with electron beams. High-energy X-rays can also be used for these purposes because their penetration in solid materials is similar to or even slightly greater than that of gamma rays. Previously, the use of X-rays had been inhibited by their slower processing rates and higher costs when compared with gamma rays. Since then, the price of cobalt-60 sources has been increased and the radiation intensity from high-energy, high-power X-ray generators has also increased. For facilities requiring at least 2 MCi of cobalt-60, the capital and operating costs of X-ray facilities with equivalent processing rates can be less than that of gamma-ray irradiators. Several high-energy electron beam facilities have been equipped with removable X-ray targets so that irradiation processes can be done with either type of ionizing energy. A new facility is now being built which will be used exclusively in the X-ray mode to sterilize medical products. Operation of this facility will show that high-energy, high-power X-ray generators are practical alternatives to large gamma-ray sources. (author)

  4. Experimental Studies of Elementary Particle Interactions at High Energies

    Energy Technology Data Exchange (ETDEWEB)

    Goulianos, Konstantin [Rockefeller Univ., New York, NY (United States)

    2013-07-30

    This is the final report of a program of research on "Experimental Studies of Elementary Particle Interactions at High Energies'' of the High Energy Physics (HEP) group of The Rockefeller University. The research was carried out using the Collider Detector at Fermilab (CDF) and the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) at CERN. Three faculty members, two research associates, and two postdoctoral associates participated in this project. At CDF, we studied proton-antiproton collisions at an energy of 1.96 TeV. We focused on diffractive interactions, in which the colliding antiproton loses a small fraction of its momentum, typically less than 1%, while the proton is excited into a high mass state retaining its quantum numbers. The study of such collisions provides insight into the nature of the diffractive exchange, conventionally referred to as Pomeron exchange. In studies of W and Z production, we found results that point to a QCD-based interpretation of the diffractive exchange, as predicted in a data-driven phenomenology developed within the Rockefeller HEP group. At CMS, we worked on diffraction, supersymmetry (SUSY), dark matter, large extra dimensions, and statistical applications to data analysis projects. In diffraction, we extended our CDF studies to higher energies working on two fronts: measurement of the single/double diffraction and of the rapidity gap cross sections at 7 TeV, and development of a simulation of diffractive processes along the lines of our successful model used at CDF. Working with the PYTHIA8 Monte Carlo simulation authors, we implemented our model as a PYTHIA8-MBR option in PYTHIA8 and used it in our data analysis. Preliminary results indicate good agreement. We searched for SUSY by measuring parameters in the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM) and found results which, combined with other experimental constraints and theoretical considerations, indicate

  5. Complex of programs for calculating radiation fields outside plane protecting shields, bombarded by high-energy nucleons

    International Nuclear Information System (INIS)

    Gel'fand, E.K.; Man'ko, B.V.; Serov, A.Ya.; Sychev, B.S.

    1979-01-01

    A complex of programs for modelling various radiation situations at high energy proton accelerators is considered. The programs are divided into there main groups according to their purposes. The first group includes programs for preparing constants describing the processes of different particle interaction with a substanc The second group of programs calculates the complete function of particle distribution arising in shields under irradiation by high energy nucleons. Concrete radiation situations arising at high energy proton accelerators are calculated by means of the programs of the third group. A list of programs as well as their short characteristic are given

  6. Ab-initio Pulsar Magnetosphere: Particle Acceleration in Oblique Rotators and High-energy Emission Modeling

    Science.gov (United States)

    Philippov, Alexander A.; Spitkovsky, Anatoly

    2018-03-01

    We perform global particle-in-cell simulations of pulsar magnetospheres, including pair production, ion extraction from the surface, frame-dragging corrections, and high-energy photon emission and propagation. In the case of oblique rotators, the effects of general relativity increase the fraction of the open field lines that support active pair discharge. We find that the plasma density and particle energy flux in the pulsar wind are highly non-uniform with latitude. A significant fraction of the outgoing particle energy flux is carried by energetic ions, which are extracted from the stellar surface. Their energies may extend up to a large fraction of the open field line voltage, making them interesting candidates for ultra-high-energy cosmic rays. We show that pulsar gamma-ray radiation is dominated by synchrotron emission, produced by particles that are energized by relativistic magnetic reconnection close to the Y-point and in the equatorial current sheet. In most cases, the calculated light curves contain two strong peaks, which is in general agreement with Fermi observations. The radiative efficiency decreases with increasing pulsar inclination and increasing efficiency of pair production in the current sheet, which explains the observed scatter in L γ versus \\dot{E}. We find that the high-frequency cutoff in the spectra is regulated by the pair-loading of the current sheet. Our findings lay the foundation for quantitative interpretation of Fermi observations of gamma-ray pulsars.

  7. A study of build-up effects in high-energy radiation fields using a TEPC

    Energy Technology Data Exchange (ETDEWEB)

    Hoefert, M; Stevenson, G R [CERN, European Laboratory for Particle Physics, Geneva (Switzerland); Aroua, A [IAR, Institute for Applied Radiophysics, Lausanne (Switzerland); Sannikov, A V [IHEP, Institute for High-Energy Physics, Protvino (Russian Federation)

    1995-09-04

    A dose of 2 mSv close to the body surface of a pregnant woman is considered by ICRP to assure a dose limit of 1 mSv to the foetus. Such an assumption depends on the energy spectrum and composition of the external radiation field and it was tested in radiation fields containing high-energy particles similar to those found around high-energy particle accelerators and in air-craft. Measurements of dose and dose equivalent were performed as a function of wall thickness using a tissue-equivalent proportional counter (TEPC) in radiation fields at the CERN-EU Reference Radiation Facility. Results are presented both with respect to integral quantities and event size spectra. The decrease in dose and dose equivalent at a depth equivalent to that of the foetus was typically 10% in a high-energy stray radiation field and in the case of PuBe source neutrons amounted to only 30%. It is concluded that it would be prudent under such exposure conditions to limit the dose of a pregnant woman to 1 mSv in order to assure that the dose to the foetus remains below the same limit. (author)

  8. A study of build-up effects in high-energy radiation fields using a TEPC

    International Nuclear Information System (INIS)

    Hoefert, M.; Stevenson, G.R.; Aroua, A.; Sannikov, A.V.

    1995-01-01

    A dose of 2 mSv close to the body surface of a pregnant woman is considered by ICRP to assure a dose limit of 1 mSv to the foetus. Such an assumption depends on the energy spectrum and composition of the external radiation field and it was tested in radiation fields containing high-energy particles similar to those found around high-energy particle accelerators and in air-craft. Measurements of dose and dose equivalent were performed as a function of wall thickness using a tissue-equivalent proportional counter (TEPC) in radiation fields at the CERN-EU Reference Radiation Facility. Results are presented both with respect to integral quantities and event size spectra. The decrease in dose and dose equivalent at a depth equivalent to that of the foetus was typically 10% in a high-energy stray radiation field and in the case of PuBe source neutrons amounted to only 30%. It is concluded that it would be prudent under such exposure conditions to limit the dose of a pregnant woman to 1 mSv in order to assure that the dose to the foetus remains below the same limit. (author)

  9. Nuclear emulsion experiments on particle production at high energies

    International Nuclear Information System (INIS)

    Otterlund, I.

    1976-08-01

    Various experimental results, including multiplicities of shower-particles and heavy prong particles, correlations between them and single particle distributions, from proton-emulsion nucleus reactions in the energy range 200-400 GeV are presented. (Auth.)

  10. On the efficiency of high-energy particle identification statistical methods

    International Nuclear Information System (INIS)

    Chilingaryan, A.A.

    1982-01-01

    An attempt is made to analyze the statistical methods of making decisions on the high-energy particle identification. The Bayesian approach is shown to provide the most complete account of the primary discriminative information between the particles of various tupes. It does not impose rigid requirements on the density form of the probability function and ensures the account of the a priori information as compared with the Neyman-Pearson approach, the mimimax technique and the heristic rules of the decision limits construction in the variant region of the specially chosen parameter. The methods based on the concept of the nearest neighbourhood are shown to be the most effective one among the local methods of the probability function density estimation. The probability distances between the training sample classes are suggested to make a decision on selecting the high-energy particle detector optimal parameters. The method proposed and the software constructed are tested on the problem of the cosmic radiation hadron identification by means of transition radiation detectors (the ''PION'' experiment)

  11. PREFACE: The EPS High Energy Particle Physics Conference

    Science.gov (United States)

    Barlow, Roger

    2008-03-01

    HEPP2007, the EPS High Energy Particle Physics Conference, was held in Manchester from July 19-26 2007. It brought together 580 delegates across the whole subject: from string theorists to detector technologists, from young postgraduate students to senior professors. Geographically they came from the UK, from the rest of Europe, from North America, and from the rest of the world. It covered the whole spectrum of the subject, not only accelerator-based experiments but also its astrophysical and cosmological aspects. The parallel and plenary talks can be found in these proceedings. A key feature of the conference, as always, was the award of the prizes: this year the EPS prize was awarded to Makoto Kobayashi and Toshihide Maskawa for their explanation of CP violation with a 6 quark model—Kobayashi came to accept it in person. The Gribov medal went to Niklas Beisert, the outreach prize to Richard Jacobsson and Charles Timmermans and the Young Physicist prizer to I Furic, G Gomez-Ceballos and S Menzemer. Parallel sessions were held in Manchester University, and plenary talks were held in the Bridgewater Hall in Manchester Town centre, a magnificent modern venue whose positive and co-operative staff enabled the conference to make the most of the impressive surroundings. We were able to put the hall to its proper purpose one evening with a concert by the Fairey Band—one of the distinctive brass bands who form part of the rich musical tradition of the North of England, and came as something new and different to many of the delegates. The conference ran smoothly and successfully, thanks largely to hard work by the local organising committee who devoted a lot of time to planning, producing ideas, and anticipating potential problems. Many of them were not from Manchester itself but from other universities and laboratories in the North of England, so their dedication was especially appreciated. The EPS committee also played a major part, by the selection of plenary

  12. Shielding technology for high energy radiation production facility

    International Nuclear Information System (INIS)

    Lee, Byung Chul; Kim, Heon Il

    2004-06-01

    In order to develop shielding technology for high energy radiation production facility, references and data for high energy neutron shielding are searched and collected, and calculations to obtain the characteristics of neutron shield materials are performed. For the evaluation of characteristics of neutron shield material, it is chosen not only general shield materials such as concrete, polyethylene, etc., but also KAERI developed neutron shields of High Density PolyEthylene (HDPE) mixed with boron compound (B 2 O 3 , H 2 BO 3 , Borax). Neutron attenuation coefficients for these materials are obtained for later use in shielding design. The effect of source shape and source angular distribution on the shielding characteristics for several shield materials is examined. This effect can contribute to create shielding concept in case of no detail source information. It is also evaluated the effect of the arrangement of shield materials using current shield materials. With these results, conceptual shielding design for PET cyclotron is performed. The shielding composite using HDPE and concrete is selected to meet the target dose rate outside the composite, and the dose evaluation is performed by configuring the facility room conceptually. From the result, the proper shield configuration for this PET cyclotron is proposed

  13. High-energy nuclear optics of polarized particles

    CERN Document Server

    Baryshevsky, Vladimir G

    2012-01-01

    The various phenomena caused by refraction and diffraction of polarized elementary particles in matter have opened up a new research area in the particle physics: nuclear optics of polarized particles. Effects similar to the well-known optical phenomena such as birefringence and Faraday effects, exist also in particle physics, though the particle wavelength is much less than the distance between atoms of matter. Current knowledge of the quasi-optical effects, which exist for all particles in any wavelength range (and energies from low to extremely high), will enable us to investigate different properties of interacting particles (nuclei) in a new aspect. This pioneering book will provide detailed accounts of quasi-optical phenomena in the particle polarization, and will interest physicists and professionals in experimental particle physics.

  14. Radiative polarization in high-energy storage rings

    International Nuclear Information System (INIS)

    Mane, S.R.

    1989-01-01

    Electron and positron beams circulating in high-energy storage rings become spontaneously polarized by the emission of synchrotron radiation. The asymptotic degree of polarization that can be attained is strongly affected by so-called depolarizing resonances. Detailed experimental measurements of the polarization were made SPEAR about ten years ago, but due to lack of a suitable theory only a limited theoretical fit to the data has so far been achieved. The author presents a general formalism for calculating depolarizing resonances, which has been coded into a computer program called SMILE, and use it to fit the SPEAR data. By the use of suitable approximations, the author is able to fit both higher order and nonlinear resonances, and thereby to interpret many hitherto unexplained features in the data, and to resolve a puzzle concerning the asymmetry of certain resonance widths seen in the data. 18 refs., 2 figs

  15. Graphical User Interface for High Energy Multi-Particle Transport, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Computer codes such as MCNPX now have the capability to transport most high energy particle types (34 particle types now supported in MCNPX) with energies extending...

  16. Graphical User Interface for High Energy Multi-Particle Transport, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Computer codes such as MCNPX now have the capability to transport most high energy particle types (34 particle types now supported in MCNPX) with energies extending...

  17. Comparison of high-energy trapped particle environments at the Earth and Jupiter.

    Science.gov (United States)

    Jun, Insoo; Garrett, Henry B

    2005-01-01

    The 'Van Allen belts' of the trapped energetic particles in the Earth's magnetosphere were discovered by the Explorer I satellite in 1958. In addition, in 1959, it was observed that UHF radio emissions from Jupiter probably had a similar source--the Jovian radiation belts. In this paper, the global characteristics of these two planets' trapped radiation environments and respective magnetospheres are compared and state-of-the-art models used to generate estimates of the high-energy electron (> or = 100 keV) and proton (> or = 1 MeV) populations--the dominant radiation particles in these environments. The models used are the AP8/AE8 series for the Earth and the Divine-Garrett/GIRE model for Jupiter. To illustrate the relative magnitude of radiation effects at each planet, radiation transport calculations were performed to compute the total ionising dose levels at the geosynchronous orbit for the Earth and at Europa (Jupiter's 4th largest moon) for Jupiter. The results show that the dose rates are -0.1 krad(Si) d(-1) at the geosynchronous orbit and -30 krad(Si) d((-1) at Europa for a 2.5 mm spherical shell aluminium shield--a factor of -300 between the two planets.

  18. Comparison of high-energy trapped particle environments at the earth and jupiter

    International Nuclear Information System (INIS)

    Jun, I.; Garrett, H. B.

    2005-01-01

    The 'Van Allen belts' of the trapped energetic particles in the Earth's magnetosphere were discovered by the Explorer I satellite in 1958. In addition, in 1959, it was observed that UHF radio emissions from Jupiter probably had a similar source - The Jovian radiation belts. In this paper, the global characteristics of these two planets' trapped radiation environments and respective magnetospheres are compared and state-of-the-art models used to generate estimates of the high-energy electron (≥100 keV) and proton ≥1 MeV) populations - The dominant radiation particles in these environments. The models used are the AP8/ AE8 series for the Earth and the Divine-Garrett/GIRE model for Jupiter. To illustrate the relative magnitude of radiation effects at each planet, radiation transport calculations were performed to compute the total ionising dose levels at the geosynchronous orbit for the Earth and at Europa (Jupiter's 4. largest moon) for Jupiter. The results show that the dose rates are ∼0.1 krad(Si) d -1 at the geosynchronous orbit and ∼30 krad(Si) d -1 at Europa for a 2.5 mm spherical shell aluminium shield - a factor of ∼300 between the two planets. (authors)

  19. Characterization of CERN-EU high energy reference radiation fields with recombination chamber

    International Nuclear Information System (INIS)

    Golnik, N.

    1998-01-01

    The CERN-EU reference radiation field facility (called CERFF) is available behind a shielding of high-energy particles beam at CERN since 1993. At present the parameters of the radiation from beam target are well investigated, however, there are still some serious doubts concerning contribution of low-LET concurrent radiation. This paper presents an experimental procedure for determination of the contribution from the concurrent radiation by measuring the absorbed dose and recombination index of radiation quality at different beam intensities. Additionally, the values of H * (10) were measured in several measuring locations. Measurements were performed with a REM-2 recombination chamber and compared with those obtained by using a HANDI-TEPC instrument. (author)

  20. Particles colliders at the Large High Energy Laboratories

    International Nuclear Information System (INIS)

    Aguilar, M.

    1996-01-01

    In this work we present an elementary introduction to particle accelerators, a basic guide of existing colliders and a description of the large european laboratories devoted to Elementary Particle Physics. This work is a large, corrected and updated version of an article published in: Ciencia-Tecnologia-Medio Ambiente Annual report 1996 Edition el Pais (Author)

  1. Inelastic two composite particle systems scattering at high energy

    International Nuclear Information System (INIS)

    Zhang Yushun.

    1986-11-01

    In this paper, by using the collective coordinate of Bohr and phenomenological deformed optical potentials, the scattering amplitudes of two composite particle systems can be obtained and the collective excitation for two composite particle systems in the scattering process is discussed. (author). 10 refs, 6 figs, 2 tabs

  2. High energy particle detectors utilizing cryogenic charge storage

    Energy Technology Data Exchange (ETDEWEB)

    Coon, D; Engels, E Jr; Plants, D; Shepard, P F; Yang, Y [Pittsburgh Univ., PA (USA); Sopira, M; Papania, R [Westinghouse Research and Development Labs., Monroeville, PA (USA)

    1984-09-15

    The mechanism of cryogenic charge storage as a method of particle detection is reviewed. A description of a simple multielement strip detector operated in this mode is given, and partial results on its operating characteristics presented.

  3. Shutter designed to block high-energy particle beams

    International Nuclear Information System (INIS)

    Donnadille, B.

    1976-01-01

    A description is given of a shutter designed for temporarily closing off an opening formed in the wall of an irradiation room for the passage of a particle beam. A cylindrical metal block can rotate about its axis and occupy two stable positions which are 180 0 from one another. A cylindrical cage closed at its two ends by two circular plates is equipped respectively with eccentric holes for the passage of the particle beam. The block is provided with a longitudinal passage through which there can pass the particle beam and a blind hole or ''pit'' disposed symmetrically to the longitudinal passage and which can block the particle beam according to the positioning of the block by respect with the eccentric holes

  4. EVOLUTION OF HIGH-ENERGY PARTICLE DISTRIBUTION IN MATURE SHELL-TYPE SUPERNOVA REMNANTS

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Houdun; Xin, Yuliang; Liu, Siming; Zhang, Shuinai [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Jokipii, J. R. [University of Arizona, Tucson, Arizona, 85721 (United States); Zhang, Li, E-mail: zhd@pmo.ac.cn, E-mail: liusm@pmo.ac.cn [Key Laboratory of Astroparticle Physics of Yunnan Province, Kunming, 650091 (China)

    2017-01-10

    Multi-wavelength observations of mature supernova remnants (SNRs), especially with recent advances in γ -ray astronomy, make it possible to constrain energy distribution of energetic particles within these remnants. In consideration of the SNR origin of Galactic cosmic rays and physics related to particle acceleration and radiative processes, we use a simple one-zone model to fit the nonthermal emission spectra of three shell-type SNRs located within 2° on the sky: RX J1713.7−3946, CTB 37B, and CTB 37A. Although radio images of these three sources all show a shell (or half-shell) structure, their radio, X-ray, and γ -ray spectra are quite different, offering an ideal case to explore evolution of energetic particle distribution in SNRs. Our spectral fitting shows that (1) the particle distribution becomes harder with aging of these SNRs, implying a continuous acceleration process, and the particle distributions of CTB 37A and CTB 37B in the GeV range are harder than the hardest distribution that can be produced at a shock via the linear diffusive shock particle acceleration process, so spatial transport may play a role; (2) the energy loss timescale of electrons at the high-energy cutoff due to synchrotron radiation appears to be always a bit (within a factor of a few) shorter than the age of the corresponding remnant, which also requires continuous particle acceleration; (3) double power-law distributions are needed to fit the spectra of CTB 37B and CTB 37A, which may be attributed to shock interaction with molecular clouds.

  5. Lattice Design in High-energy Particle Accelerators

    CERN Document Server

    Holzer, B.J.

    2014-01-01

    This lecture gives an introduction into the design of high-energy storage ring lattices. Applying the formalism that has been established in transverse be am optics, the basic principles of the development of a magnet lattice are explained and the characteristics of the resulting magnet structure are discussed. The periodic assembly of a storage ring cell with its boundary conditions concerning stability and scaling of the beam optics parameters is addressed as well as special lattice insertions such as drifts, mini beta sections, dispersion suppressors, etc. In addition to the exact calculations that are indispensable for a rigorous treatment of the matter, scaling rules are shown and simple rules of thumb are included that enable the lattice designer to do the first estimates and get the basic numbers ‘ on the back of an envelope.

  6. A practical guide to modern high energy particle accelerators

    International Nuclear Information System (INIS)

    Holmes, S.D.

    1987-10-01

    The purpose of these lectures is to convey an understanding of how particle accelerators work and why they look the way they do. The approach taken is physically intuitive rather than mathematically rigorous. The emphasis is on the description of proton circular accelerators and colliders. Linear accelerators are mentioned only in passing as sources of protons for higher energy rings. Electron accelerators/storage rings and antiproton sources are discussed only by way of brief descriptions of the features which distinguish them from proton accelerators. The basics of how generic accelerators work are discussed, focusing on descriptions of what sets the overall scale, single particle dynamics and stability, and descriptions of the phase space of the particle beam, the information thus presented is then used to go through the exercise of designing a Superconducting Super Collider

  7. Particle production in high energy nucleus-nucleus collisions

    International Nuclear Information System (INIS)

    Stock, R.

    1985-05-01

    Recent data on the production of pions and strange particles at the Bevalac and Synchrophasotron accelerators are reviewed, covering pion spectra and multiplicity distributions, Λ, K + and K - yields and spectra, and Λ polarization. Emphasis is placed on recent progress in determining the equation of state of compressed fireball nuclear matter from the observed pion yield in central collisions. Further, the information derived from apparent spectral temperatures is critically examined, along with a discussion of thermal and chemical equilibrium attainment in the reactions, as revealed by particle spectra and yields. (orig.)

  8. High energy charged particle registration in CR-39 polycarbonated detector

    International Nuclear Information System (INIS)

    Abdel-Wahab, M.S.; El Enany, N.; El Fiki, S.; Eissa, H.M.; El-Adl, E.H.; El-Feky, M.A.

    1991-01-01

    Track etch rate characteristics of CR-39 plastic detector exposed to 28 Si ions of 670 MeV energy have been investigated. Experimental results were obtained in terms of frequency distribution of the track diameter, track density and bulk etching rate. A dependence of the mean track diameter on energy was found. The application of the radiation effect of heavy ions on CR-39 in the field of radiation detection and dosimetry are discussed. Results indicated that it is possible to produce etchable tracks of 28 Si in this energy range in CR-39. We also report the etching characteristics of these tracks in the CR-39 detector. (orig.) [de

  9. Particle accelerator physics and technology for high energy density physics research

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, D.H.H.; Blazevic, A.; Rosmej, O.N.; Spiller, P.; Tahir, N.A.; Weyrich, K. [Gesellschaft fur Schwerionenforschung, GSI-Darmstadt, Plasmaphysik, Darmstadt (Germany); Hoffmann, D.H.H.; Dafni, T.; Kuster, M.; Ni, P.; Roth, M.; Udrea, S.; Varentsov, D. [Darmstadt Univ., Institut fur Kernphysik, Technische Schlobgartenstr. 9 (Germany); Jacoby, J. [Frankfurt Univ., Institut fur Angewandte Physik (Germany); Kain, V.; Schmidt, R.; Zioutas, K. [European Organization for Nuclear Research (CERN), Geneve (Switzerland); Zioutas, K. [Patras Univ., Dept. of Physics (Greece); Mintsev, V.; Fortov, V.E. [Russian Academy of Sciences, Institute of Problems of Chemical Physics, Chernogolovka (Russian Federation); Sharkov, B.Y. [Institut for Theoretical and Experimental Physics ITEP, Moscow (Russian Federation)

    2007-08-15

    Interaction phenomena of intense ion- and laser radiation with matter have a large range of application in different fields of science, extending from basic research of plasma properties to applications in energy science, especially in inertial fusion. The heavy ion synchrotron at GSI now routinely delivers intense uranium beams that deposit about 1 kJ/g of specific energy in solid matter, e.g. solid lead. Our simulations show that the new accelerator complex FAIR (Facility for Antiproton and Ion Research) at GSI as well as beams from the CERN large hadron collider (LHC) will vastly extend the accessible parameter range for high energy density states. A natural example of hot dense plasma is provided by our neighbouring star the sun, and allows a deep insight into the physics of fusion, the properties of matter at high energy density, and is moreover an excellent laboratory for astro-particle physics. As such the sun's interior plasma can even be used to probe the existence of novel particles and dark matter candidates. We present an overview on recent results and developments of dense plasma physics addressed with heavy ion and laser beams combined with accelerator- and nuclear physics technology. (authors)

  10. Fully integrated CMOS pixel detector for high energy particles

    International Nuclear Information System (INIS)

    Vanstraelen, G.; Debusschere, I.; Claeys, C.; Declerck, G.

    1989-01-01

    A novel type of position and energy sensitive, monolithic pixel array with integrated readout electronics is proposed. Special features of the design are a reduction of the number of output channels and of the amount of output data, and the use of transistors on the high resistivity silicon. The number of output channels for the detector array is reduced by handling in parallel a number of pixels, chosen as a function of the time resolution required for the system, and by the use of an address decoder. A further reduction of data is achieved by reading out only those pixels which have been activated. The pixel detector circuit will be realized in a 3 μm p-well CMOS process, which is optimized for the full integration of readout electronics and detector diodes on high resistivity Si. A retrograde well is formed by means of a high energy implantation, followed by the appropriate temperature steps. The optimization of the well shape takes into account the high substrate bias applied during the detector operation. The design is largely based on the use of MOS transistors on the high resistivity silicon itself. These have proven to perform as well as transistors on standard doped substrate. The basic building elements as well as the design strategy of the integrated pixel detector are presented in detail. (orig.)

  11. Biological Effects of Particles with Very High Energy Deposition on Mammalian Cells Utilizing the Brookhaven Tandem Van de Graaff Accelerator

    Science.gov (United States)

    Saha, Janapriya; Cucinotta, Francis A.; Wang, Minli

    2013-01-01

    High LET radiation from GCR (Galactic Cosmic Rays) consisting mainly of high charge and energy (HZE) nuclei and secondary protons and neutrons, and secondaries from protons in SPE (Solar Particle Event) pose a major health risk to astronauts due to induction of DNA damage and oxidative stress. Experiments with high energy particles mimicking the space environment for estimation of radiation risk are being performed at NASA Space Radiation Laboratory at BNL. Experiments with low energy particles comparing to high energy particles of similar LET are of interest for investigation of the role of track structure on biological effects. For this purpose, we report results utilizing the Tandem Van de Graaff accelerator at BNL. The primary objective of our studies is to elucidate the influence of high vs low energy deposition on track structure, delta ray contribution and resulting biological responses. These low energy ions are of special relevance as these energies may occur following absorption through the spacecraft and shielding materials in human tissues and nuclear fragments produced in tissues by high energy protons and neutrons. This study will help to verify the efficiency of these low energy particles and better understand how various cell types respond to them.

  12. Aerosol nucleation induced by a high energy particle beam

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker; Pedersen, Jens Olaf Pepke; Uggerhøj, Ulrik I.

    2011-01-01

    We have studied sulfuric acid aerosol nucleation in an atmospheric pressure reaction chamber using a 580 MeV electron beam to ionize the volume of the reaction chamber. We find a clear contribution from ion-induced nucleation and consider this to be the first unambiguous observation of the ion......-effect on aerosol nucleation using a particle beam under conditions that resemble the Earth's atmosphere. By comparison with ionization using a gamma source we further show that the nature of the ionizing particles is not important for the ion-induced component of the nucleation. This implies that inexpensive...... ionization sources - as opposed to expensive accelerator beams - can be used for investigations of ion-induced nucleation....

  13. Scattering of high-energy α particles on 12C

    International Nuclear Information System (INIS)

    Ahmad, I.

    1977-04-01

    Glauber multiple scattering theory is applied to analyse the elastic and inelastic scattering of 1.37 GeV α particles on 12 C. An approach which treats the N-α amplitude at the incident nucleon kinetic energy equal to the α-kinetic energy per particle as the basic interaction is adopted. Using the gaussian model for 4 He to obtain the N-α amplitude in terms of the NN amplitude, it is found that, in general, the experimental data are qualitatively explained. However, large discrepancies in terms of the magnitude of the cross-sections in the small angle region and the positions of the minima in the angular distribution at larger angles are generally present. Effects of the two-body correlations in the projectile as well as in the target are also investigated

  14. Particle size of radioactive aerosols generated during machine operation in high-energy proton accelerators

    International Nuclear Information System (INIS)

    Oki, Yuichi; Kanda, Yukio; Kondo, Kenjiro; Endo, Akira

    2000-01-01

    In high-energy accelerators, non-radioactive aerosols are abundantly generated due to high radiation doses during machine operation. Under such a condition, radioactive atoms, which are produced through various nuclear reactions in the air of accelerator tunnels, form radioactive aerosols. These aerosols might be inhaled by workers who enter the tunnel just after the beam stop. Their particle size is very important information for estimation of internal exposure doses. In this work, focusing on typical radionuclides such as 7 Be and 24 Na, their particle size distributions are studied. An aluminum chamber was placed in the EP2 beam line of the 12-GeV proton synchrotron at High Energy Accelerator Research Organization (KEK). Aerosol-free air was introduced to the chamber, and aerosols formed in the chamber were sampled during machine operation. A screen-type diffusion battery was employed in the aerosol-size analysis. Assuming that the aerosols have log-normal size distributions, their size distributions were obtained from the radioactivity concentrations at the entrance and exit of the diffusion battery. Radioactivity of the aerosols was measured with Ge detector system, and concentrations of non-radioactive aerosols were obtained using condensation particle counter (CPC). The aerosol size (radius) for 7 Be and 24 Na was found to be 0.01-0.04 μm, and was always larger than that for non-radioactive aerosols. The concentration of non-radioactive aerosols was found to be 10 6 - 10 7 particles/cm 3 . The size for radioactive aerosols was much smaller than ordinary atmospheric aerosols. Internal doses due to inhalation of the radioactive aerosols were estimated, based on the respiratory tract model of ICRP Pub. 66. (author)

  15. Modeling the radar scatter off of high-energy neutrino-induced particle cascades in ice

    NARCIS (Netherlands)

    de Vries, Krijn D.; van Eijndhoven, Nick; O'Murchadha, Aongus; Toscano, Simona; Scholten, Olaf

    2017-01-01

    We discuss the radar detection method as a probe for high-energy neutrino induced particle cascades in ice. In a previous work we showed that the radar detection techniqe is a promising method to probe the high-energy cosmic neutrino flux above PeV energies. This was done by considering a simplified

  16. Load management strategy for Particle-In-Cell simulations in high energy particle acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Beck, A., E-mail: beck@llr.in2p3.fr [Laboratoire Leprince-Ringuet, École polytechnique, CNRS-IN2P3, Palaiseau 91128 (France); Frederiksen, J.T. [Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 København Ø (Denmark); Dérouillat, J. [CEA, Maison de La Simulation, 91400 Saclay (France)

    2016-09-01

    In the wake of the intense effort made for the experimental CILEX project, numerical simulation campaigns have been carried out in order to finalize the design of the facility and to identify optimal laser and plasma parameters. These simulations bring, of course, important insight into the fundamental physics at play. As a by-product, they also characterize the quality of our theoretical and numerical models. In this paper, we compare the results given by different codes and point out algorithmic limitations both in terms of physical accuracy and computational performances. These limitations are illustrated in the context of electron laser wakefield acceleration (LWFA). The main limitation we identify in state-of-the-art Particle-In-Cell (PIC) codes is computational load imbalance. We propose an innovative algorithm to deal with this specific issue as well as milestones towards a modern, accurate high-performance PIC code for high energy particle acceleration.

  17. Low-energy particle production and residual nuclei production from high-energy hadron-nucleus collisions

    International Nuclear Information System (INIS)

    Alsmiller, F.S.; Alsmiller, R.G. Jr.; Hermann, O.W.

    1987-01-01

    The high-energy hadron-nucleus collision model, EVENTQ, has been modified to include a calculation of the excitation and kinetic energy of the residual compound nucleus. The specific purpose of the modification is to make it possible to use the model in the high-energy radiation transport code, HETC, which, in conjunction with MORSE, is used to transport the low energy particles. It is assumed that the nucleons in the nucleus move in a one-dimensional potential well and have the momentum distribution of a degenerate Fermi gas. The low energy particles produced by the deexcitation of the residual compound nucleus, and the final residual nucleus, are determined from an evaporation model. Comparisons of multiplicities and residual nuclei distributions with experimental data are given. The ''grey'' particles, i.e., charged particles with 0.25 < β < 0.7, are in good agreement with experimental data but the residual nuclei distributions are not. 12 refs., 3 figs

  18. An investigation of build-up effects in high energy radiation fields using a Handi TEPC

    International Nuclear Information System (INIS)

    Aroua, A.; Sannikov, A.V.

    1995-01-01

    ICRP considers that a dose limit of 2 mSv close to the body surface of a pregnant woman will ensure a dose limit of 1 mSv to the foetus. This assumption depends on the energy spectrum and composition of the radiation fields, especially those containing high energy particles such as are found around particle accelerators or in aircraft. In this work the response of a tissue-equivalent proportional counter in radiation fields of different composition and energy was measured as a function of depth in cylindrical phantoms. The decrease in dose and dose equivalent at a phantom depth equivalent to that of a foetus was 10% in a typical high energy stray radiation field and 30% for neutrons from a Pu-Be source. It is concluded that it would be prudent in these cases to limit the exposure of a pregnant woman to 1 mSv in order to ensure that the dose to the foetus stays below the same limit. (Author)

  19. Equipment and detectors calibration behind shielding of CERN high-energy particle accelerator SPS: June 2007

    International Nuclear Information System (INIS)

    Spurny, Frantisek; Ploc, Ondrej

    2008-02-01

    High energy stray radiation fields have been realised since 1993 at CERN also in the frame of CEC-CERN collaboration on the project: 'Detection and the Dosimetry of Neutrons and Charged Particles at Aviation Altitudes in the Earth's Atmosphere'. They are formed at the H6 beam of the north experimental area of the SPS facility. Two shielding configurations have been built, with the top concrete, resp. top iron shielding. Many intercalibration experiments have been realised since the beginning. After an interruption due to technical problems, two other campaigns have been realised during 2006 year, another one during the June 2007. This report describes analyses and discusses the most of results obtained during the last, 2007 run.. (author)

  20. Aerosol nucleation induced by a high energy particle beam

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker; Pedersen, Jens Olaf Pepke; Uggerhøj, Ulrik I.

    The effect of ions in aerosol nucleation is a subject where much remains to be discovered. That ions can enhance nucleation has been shown by theory, observations, and experiments. However, the exact mechanism still remains to be determined. One question is if the nature of the ionization affects...... the nucleation. This is an essential question since many experiments have been performed using radioactive sources that ionize differently than the cosmic rays which are responsible for the majority of atmospheric ionization. Here we report on an experimental study of sulphuric acid aerosol nucleation under near...... atmospheric conditions using a 580 MeV electron beam to ionize the volume of the reaction chamber. We find a clear and significant contribution from ion induced nucleation and consider this to be an unambiguous observation of the ion-effect on aerosol nucleation using a particle beam under conditions not far...

  1. High-energy collisions of particles, strings, and branes

    CERN Document Server

    Veneziano, Gabriele

    2015-01-01

    This chapter summarizes some 25 years of work on the transplanckian-energy collisions of particles, strings, and branes, seen as a theoretical laboratory for understanding how gravity and quantum mechanics can be consistently combined in string theory. The ultimate aim of the exercise is to understand whether and how a consistent quantization of gravity can solve some longstanding paradoxes, such as the apparent loss of information in the production and decay of black holes at a semiclassical level. Considerable progress has been made in understanding the emergence of General Relativity expectations and in evaluating several kinds of quantum string corrections to them in the weak-gravity regime while keeping unitarity manifest. While some progress has also been made in the strong-gravity/gravitational collapse domain, full control of how unitarity works in that regime is still lacking.

  2. Radiation tolerant fiber optic humidity sensors for High Energy Physics applications

    CERN Document Server

    Berruti, Gaia Maria; Cusano, Andrea

    This work is devoted to the development of fiber optic humidity sensors to be applied in high-energy physics applications and in particular in experiments currently running at CERN. The high radiation level resulting from the operation of the accelerator at full luminosity can cause serious performance deterioration of the silicon sensors which are responsible for the particle tracking. To increase their lifetime, the sensors must be kept cold at temperatures below 0 C. At such low temperatures, any condensation risk has to be prevented and a precise thermal and hygrometric control of the air filling and surrounding the tracker detector cold volumes is mandatory. The technologies proposed at CERN for relative humidity monitoring are mainly based on capacitive sensing elements which are not designed with radiation resistance characteristic. In this scenario, fiber optic sensors seem to be perfectly suitable. Indeed, the fiber itself, if properly selected, can tolerate a very high level of radiation, optical fi...

  3. Observations of visual sensations produced by Cerenkov radiation from high-energy electrons

    International Nuclear Information System (INIS)

    Steidley, K.D.; Eastman, R.M.; Stabile, R.J.

    1989-01-01

    Ten cancer patients whose eyes were therapeutically irradiated with 6-18 MeV electrons reported visual light sensations. Nine reported seeing blue light and one reported seeing white light. Controls reported seeing no light. Additionally, tests with patients ruled out the x-ray contamination of the electron beam as being important. The photon yield due to Cerenkov radiation produced by radium and its daughters for both electrons and gamma rays was calculated; it was found to account for a turn-of-the-century human observation of the radium phosphene. We conclude that the dominant mechanism of this phosphene is Cerenkov radiation, primarily from betas. From our own patient data, based on the color seen and the Cerenkov production rates, we conclude that the dominant mechanism is Cerenkov radiation and that high-energy electrons are an example of particle induced visual sensations

  4. Individual monitoring in high-energy stray radiation fields

    International Nuclear Information System (INIS)

    Hoefert, M.; Stevenson, G.R.

    1995-01-01

    Due to the lack of passive or active devices that could be considered as personal dosemeters in high-energy stray fields one can at present only perform individual monitoring around high energy accelerators. Of all detectors currently available it is shown that the NTA film is the most suitable method for individually monitoring the neutron exposure of more than 3000 persons regularly, reliably, and cost effectively like at CERN. (author)

  5. Frontiers of particle beam and high energy density plasma science using pulse power technology

    International Nuclear Information System (INIS)

    Masugata, Katsumi

    2011-04-01

    The papers presented at the symposium on “Frontiers of Particle Beam and High Energy Density Plasma Science using Pulse Power Technology” held in November 20-21, 2009 at National Institute for Fusion Science are collected. The papers reflect the present status and resent progress in the experiment and theoretical works on high power particle beams and high energy density plasmas produced by pulsed power technology. (author)

  6. Limiting technologies for particle beams and high energy physics

    International Nuclear Information System (INIS)

    Panofsky, W.K.H.

    1985-07-01

    Since 1930 the energy of accelerators had grown by an order of magnitude roughly every 7 years. Like all exponential growths, be they human population, the size of computers, or anything else, this eventually will have to come to an end. When will this happen to the growth of the energy of particle accelerators and colliders. Fortunately, as the energy of accelerators has grown the cost per unit energy has decreased almost as fast as has the increase in energy. The result is that while the energy has increased so dramatically the cost per new installation has increased only by roughly an order of magnitude since the 1930's (corrected for inflation), while the number of accelerators operating at the frontier of the field has shrunk. As is shown in the by now familiar Livingston chart this dramatic decrease in cost has been achieved largely by a succession of new technologies, in addition to the more moderate gains in efficiency due to improved design, economies of scale, etc. We are therefore facing two questions: (1) Is there good reason scientifically to maintain the exponential growth, and (2) Are there new technologies in sight which promise continued decreases in unit costs. The answer to the first question is definitely yes; the answer to the second question is maybe

  7. Secondary radiation dose during high-energy total body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Janiszewska, M.; Raczkowski, M. [Lower Silesian Oncology Center, Medical Physics Department, Wroclaw (Poland); Polaczek-Grelik, K. [University of Silesia, Medical Physics Department, Katowice (Poland); Szafron, B.; Konefal, A.; Zipper, W. [University of Silesia, Department of Nuclear Physics and Its Applications, Katowice (Poland)

    2014-05-15

    The goal of this work was to assess the additional dose from secondary neutrons and γ-rays generated during total body irradiation (TBI) using a medical linac X-ray beam. Nuclear reactions that occur in the accelerator construction during emission of high-energy beams in teleradiotherapy are the source of secondary radiation. Induced activity is dependent on the half-lives of the generated radionuclides, whereas neutron flux accompanies the treatment process only. The TBI procedure using a 18 MV beam (Clinac 2100) was considered. Lateral and anterior-posterior/posterior-anterior fractions were investigated during delivery of 2 Gy of therapeutic dose. Neutron and photon flux densities were measured using neutron activation analysis (NAA) and semiconductor spectrometry. The secondary dose was estimated applying the fluence-to-dose conversion coefficients. The main contribution to the secondary dose is associated with fast neutrons. The main sources of γ-radiation are the following: {sup 56}Mn in the stainless steel and {sup 187}W of the collimation system as well as positron emitters, activated via (n,γ) and (γ,n) processes, respectively. In addition to 12 Gy of therapeutic dose, the patient could receive 57.43 mSv in the studied conditions, including 4.63 μSv from activated radionuclides. Neutron dose is mainly influenced by the time of beam emission. However, it is moderated by long source-surface distances (SSD) and application of plexiglass plates covering the patient body during treatment. Secondary radiation gives the whole body a dose, which should be taken into consideration especially when one fraction of irradiation does not cover the whole body at once. (orig.) [German] Die zusaetzliche Dosis durch sekundaere Neutronen- und γ-Strahlung waehrend der Ganzkoerperbestrahlung mit Roentgenstrahlung aus medizinischen Linearbeschleunigern wurde abgeschaetzt. Bei der Emission hochenergetischer Strahlen zur Teletherapie finden hauptsaechlich im Beschleuniger

  8. On the origin of very-high-energy photons in astrophysics: a short introduction to acceleration and radiation physics

    International Nuclear Information System (INIS)

    Lemoine, M.; Pelletier, G.

    2015-01-01

    Powerful astrophysical sources produce non-thermal spectra of very-high-energy photons, with generic power-law distributions, through various radiative processes of charged particles, e.g., synchrotron radiation, inverse Compton processes, and hadronic interactions. Those charged particles have themselves been accelerated to ultra-relativistic energies in intense electromagnetic fields in the source. In many cases, the exact acceleration scheme is not known, but standard scenarios, such as Fermi mechanisms and reconnection processes are generally considered as prime suspects for the conversion of bulk kinetic or electromagnetic energy into a power law of supra-thermal particles. This paper proposes a short introduction to the various acceleration and radiative processes which shape the distributions of very-high-energy photons (E > 100 MeV) in astrophysics. (authors)

  9. Energy dependence of ulrathin LiF-dosemeters for high energy electrons and high energy X-radiation

    International Nuclear Information System (INIS)

    Kupfer, T.

    1977-02-01

    The energy dependence of ultrathin LiF-dosemeters for high energy electrons (5-40 MeV) and high energy X-radiation (6 MV, 42 MV) is experimentally determined. The experimental values are compared to values calculted earlier by other authors. The influence of the thickness of the dosemeters have been considered by comparison of experimental values for 0.03 mm thick dosemeters and theoretical values for 0.13 mm and 0.38 mm thick ones. Also different commersially available dosemeters have been compared by experiments. It is difficult to draw any other conclutions about the energy dependence than that the variation of the relative responce is within +- 3 percent (2S). However the results seems to be sulficient for clinical applications

  10. Single-field isodose charts for high-energy radiation

    International Nuclear Information System (INIS)

    1962-01-01

    The main part of this guide comprises isodose chart specifications divided into four sections: cesium-137 gamma rays, cobalt-60 gamma rays, high-energy x-rays and electron beams. In each section the information is further classified according to the equipment model and the institution of origin. 1 fig

  11. Measurement and analysis of high energy radiation through activation detectors. Application in dosimetry

    International Nuclear Information System (INIS)

    Sklavenitis, L.

    1967-10-01

    This work is concerned with the possibility of measurement and analysis of radiation fluences within objects of small volume submitted to a high energy proton beam. The first part, consecrated to the establishment of a method of analysis, comprises a detailed study of the radiation nature and energy spectra as well as of the various dosimetry methods. In order to select a group of detectors, high energy nuclear reactions were systematically studied and for some of them cross sections were measured or calculated: for example the cross section of the reaction 11 B (p,n) 11 C between 150 and 3000 MeV and of the reaction 34 S (p,2pn) 32 P between 50 and 3000 MeV. The second part is relative to the application of the fore-mentioned analysis to radiation within a tissue equivalent phantom irradiated by 3 GeV protons. This analysis is sufficiently detailed to allow the reconstitution of the absorbed doses, the dose equivalent and, contingent on a better knowledge of the dose due to heavy particles, the quality factors. It allowed also to follow the evolution of the various dosimetric data as a function of the depth inside the phantom and to verify calculations already done by other researchers. The comparison of the measured doses and the corresponding detector activities revealed the possibility that some detectors could give directly the absorbed dose, or even the dose equivalent, by a simple activity measurement. (author) [fr

  12. Radiation hardness of silicon detectors - a challenge from high-energy physics

    CERN Document Server

    Lindström, G; Fretwurst, E

    1999-01-01

    An overview of the radiation-damage-induced problems connected with the application of silicon particle detectors in future high-energy physics experiments is given. Problems arising from the expected hadron fluences are summarized and the use of the nonionizing energy loss for normalization of bulk damage is explained. The present knowledge on the deterioration effects caused by irradiation is described leading to an appropriate modeling. Examples are given for a correlation between the change in the macroscopic performance parameters and effects to be seen on the microscopic level by defect analysis. Finally possible ways are out-lined for improving the radiation tolerance of silicon detectors either by operational conditions, process technology or defect engineering.

  13. Emission of high-energy, light particles from intermediate-energy heavy-ion reactions

    International Nuclear Information System (INIS)

    Ball, J.B.; Auble, R.L.

    1982-01-01

    One of the early surprises in examining reaction products from heavy ion reactions at 10 MeV/nucleon and above was the large yield of light particles emitted and the high energies to which the spectra of these particles extended. The interpretation of the origin of the high energy light ions has evolved from a picture of projectile excitation and subsequent evaporation to one of pre-equilibrium (or nonequilibrium) emission. The time scale for particle emission has thus moved from one that occurs following the initial collision to one that occurs at the very early stages of the collision. Research at ORNL on this phenomenon is reviewed

  14. Modelling of prompt losses of high energy charged particles in Tokamaks

    International Nuclear Information System (INIS)

    Dillner, Oe.; Anderson, D.; Hamnen, H.; Lisak, M.

    1990-01-01

    A simple analytical expression for the total prompt loss fraction of high energy charged particles in an axisymmetric Tokamak is derived. The results are compared with predictions obtained from numerical simulations and show good agreement. An application is made to sawtooth induced changes in the losses of fusion generated high energy charged particles. Particular emphasis is given to the importance of sawtooth induced profile changes of the background ion densities and temperature as well as to redistribution of particles which have accumulated during the sawtooth rise but are being lost by redistribution at the sawtooth crash. (au)

  15. Numerical analysis of energy density and particle density in high energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Fu Yuanyong; Lu Zhongdao

    2004-01-01

    Energy density and particle density in high energy heavy-ion collisions are calculated with infinite series expansion method and Gauss-Laguerre formulas in numerical integration separately, and the results of these two methods are compared, the higher terms and linear terms in series expansion are also compared. The results show that Gauss-Laguerre formulas is a good method in calculations of high energy heavy-ion collisions. (author)

  16. Simulation of high-energy particle production through sausage and kink instabilities in pinched plasma discharges

    International Nuclear Information System (INIS)

    Haruki, Takayuki; Yousefi, Hamid Reza; Masugata, Katsumi; Sakai, Jun-Ichi; Mizuguchi, Yusuke; Makino, Nao; Ito, Hiroaki

    2006-01-01

    In an experimental plasma, high-energy particles were observed by using a plasma focus device, to obtain energies of a few hundred keV for electrons, up to MeV for ions. In order to study the mechanism of high-energy particle production in pinched plasma discharges, a numerical simulation was introduced. By use of a three-dimensional relativistic and fully electromagnetic particle-in-cell code, the dynamics of a Z-pinch plasma, thought to be unstable against sausage and kink instabilities, are investigated. In this work, the development of sausage and kink instabilities and subsequent high-energy particle production are shown. In the model used here, cylindrically distributed electrons and ions are driven by an external electric field. The driven particles spontaneously produce a current, which begins to pinch by the Lorentz force. Initially the pinched current is unstable against a sausage instability, and then becomes unstable against a kink instability. As a result high-energy particles are observed

  17. Charged-particle mutagenesis 2. Mutagenic effects of high energy charged particles in normal human fibroblasts

    Science.gov (United States)

    Chen, D. J.; Tsuboi, K.; Nguyen, T.; Yang, T. C.

    1994-01-01

    The biological effects of high Linear Energy Transfer (LET) charged particles are a subject of great concern with regard to the prediction of radiation risk in space. In this report, mutagenic effects of high LET charged particles are quantitatively measured using primary cultures of human skin fibroblasts, and the spectrum of induced mutations are analyzed. The LET of the charged particles ranged from 25 KeV/micrometer to 975 KeV/micrometer with particle energy (on the cells) between 94-603 MeV/u. The X-chromosome linked hypoxanthine guanine phosphoribosyl transferase (hprt) locus was used as the target gene. Exposure to these high LET charged particles resulted in exponential survival curves; whereas, mutation induction was fitted by a linear model. The Relative Biological Effect (RBE) for cell-killing ranged from 3.73 to 1.25, while that for mutant induction ranged from 5.74 to 0.48. Maximum RBE values were obtained at the LET of 150 keV/micrometer. The inactivation cross-section (alpha i) and the action cross-section for mutant induction (alpha m) ranged from 2.2 to 92.0 sq micrometer and 0.09 to 5.56 x 10(exp -3) sq micrometer respectively. The maximum values were obtained by Fe-56 with an LET of 200 keV/micrometer. The mutagenicity (alpha m/alpha i) ranged from 2.05 to 7.99 x 10(exp -5) with the maximum value at 150 keV/micrometer. Furthermore, molecular analysis of mutants induced by charged particles indicates that higher LET beams are more likely to cause larger deletions in the hprt locus.

  18. Charged-particle mutagenesis II. Mutagenic effects of high energy charged particles in normal human fibroblasts

    Science.gov (United States)

    Chen, D. J.; Tsuboi, K.; Nguyen, T.; Yang, T. C.

    1994-01-01

    The biological effects of high LET charged particles are a subject of great concern with regard to the prediction of radiation risk in space. In this report, mutagenic effects of high LET charged particles are quantitatively measured using primary cultures of human skin fibroblasts, and the spectrum of induced mutations are analyzed. The LET of the charged particles ranged from 25 KeV/micrometer to 975 KeV/micrometer with particle energy (on the cells) between 94-603 MeV/u. The X-chromosome linked hypoxanthine guanine phosphoribosyl transferase (hprt) locus was used as the target gene. Exposure to these high LET charged particles resulted in exponential survival curves; whereas, mutation induction was fitted by a linear model. The Relative Biological Effect (RBE) for cell-killing ranged from 3.73 to 1.25, while that for mutant induction ranged from 5.74 to 0.48. Maximum RBE values were obtained at the LET of 150 keV/micrometer. The inactivation cross-section (alpha i) and the action cross-section for mutant induction (alpha m) ranged from 2.2 to 92.0 micrometer2 and 0.09 to 5.56 x 10(-3) micrometer2, respectively. The maximum values were obtained by 56Fe with an LET of 200 keV/micrometer. The mutagenicity (alpha m/alpha i) ranged from 2.05 to 7.99 x 10(-5) with the maximum value at 150 keV/micrometer. Furthermore, molecular analysis of mutants induced by charged particles indicates that higher LET beams are more likely to cause larger deletions in the hprt locus.

  19. Prediction of high-energy (> 0.3 MeV) substorm-related magnetospheric particles

    International Nuclear Information System (INIS)

    Baker, D.N.; Belian, R.D.; Higbie, P.R.; Hones, E.W. Jr.

    1979-01-01

    Measurements both at 6.6 R/sub E/ and in the plasma sheet (greater than or equal to 18 R/sub E/) show that high energy substorm-accelerated particles occur preferentially when the solar wind speed (V/sub sw/) is high. Virtually no > 0.3 MeV protons, for example, are observed in association with substorms that occur when V/sub sw/ is 700 km/sec. These results suggest that realtime monitoring of interplanetary conditions could allow simple, effective prediction of high energy magnetospheric particle disturbances. 7 references

  20. Concept and computation of radiation dose at high energies

    International Nuclear Information System (INIS)

    Sarkar, P.K.

    2010-01-01

    Computational dosimetry, a subdiscipline of computational physics devoted to radiation metrology, is determination of absorbed dose and other dose related quantities by numbers. Computations are done separately both for external and internal dosimetry. The methodology used in external beam dosimetry is necessarily a combination of experimental radiation dosimetry and theoretical dose computation since it is not feasible to plan any physical dose measurements from inside a living human body

  1. A self-powered thin-film radiation detector using intrinsic high-energy current

    Energy Technology Data Exchange (ETDEWEB)

    Zygmanski, Piotr, E-mail: pzygmanski@LROC.HARVARD.EDU, E-mail: Erno-Sajo@uml.edu [Department of Radiation Oncology, Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States); Sajo, Erno, E-mail: pzygmanski@LROC.HARVARD.EDU, E-mail: Erno-Sajo@uml.edu [Department of Physics and Applied Physics, Medical Physics Program, University of Massachusetts Lowell, Lowell, Massachusetts 01854 (United States)

    2016-01-15

    Purpose: The authors introduce a radiation detection method that relies on high-energy current (HEC) formed by secondary charged particles in the detector material, which induces conduction current in an external readout circuit. Direct energy conversion of the incident radiation powers the signal formation without the need for external bias voltage or amplification. The detector the authors consider is a thin-film multilayer device, composed of alternating disparate electrically conductive and insulating layers. The optimal design of HEC detectors consists of microscopic or nanoscopic structures. Methods: Theoretical and computational developments are presented to illustrate the salient properties of the HEC detector and to demonstrate its feasibility. In this work, the authors examine single-sandwiched and periodic layers of Cu and Al, and Au and Al, ranging in thickness from 100 nm to 300 μm and separated by similarly sized dielectric gaps, exposed to 120 kVp x-ray beam (half-value thickness of 4.1 mm of Al). The energy deposition characteristics and the high-energy current were determined using radiation transport computations. Results: The authors found that in a dual-layer configuration, the signal is in the measurable range. For a defined total detector thickness in a multilayer structure, the signal sharply increases with decreasing thickness of the high-Z conductive layers. This paper focuses on the computational results while a companion paper reports the experimental findings. Conclusions: Significant advantages of the device are that it does not require external power supply and amplification to create a measurable signal; it can be made in any size and geometry, including very thin (sub-millimeter to submicron) flexible curvilinear forms, and it is inexpensive. Potential applications include medical dosimetry (both in vivo and external), radiation protection, and other settings where one or more of the above qualities are desired.

  2. Multiple Coulomb scattering of high-energy heavy charged particle beams used in biology and medicine

    International Nuclear Information System (INIS)

    Wong, M.; Schimmerling, W.; Ludewigt, B.; Phillips, M.; Curtis, S.; Tobias, C.A.

    1987-01-01

    The authors measured lateral displacement and angular distributions of high-energy heavy charged particles emerging from a target at the Lawrence Berkeley Laboratory BEVALAC with beams used in radiobiology experiments. Multiple Coulomb scattering occurring in the target material generally spreads the beam laterally and increases its divergence. The apparatus consists of four sets of position-sensitive semiconductor detectors located along the beam line. Each providing two position signals and one energy signal. The difference between the two position signals is used to determine the particle position in one dimension. The two position signals are constrained to add up to the energy deposition signal in order to reject multiple-particle traversals. The vector directions for the incident and emerging particles are reconstructed in three dimensions from their measured coordinated positions. Lateral and angular distributions are reported for beams of high-energy neon, iron and uranium ions incident on targets of aluminum, cooper, lead and water

  3. Radiative corrections to high-energy neutrino scattering

    International Nuclear Information System (INIS)

    Rujula, A. de; Petronzio, R.; Savoy-Navarro, A.

    1979-01-01

    Motivated by precise neutrino experiments, the electromagnetic radiative corrections to the data are reconsidered. The usefulness is investigated and the simplicity demonstrated of the 'leading log' approximation: the calculation to order α ln (Q/μ), α ln (Q/msub(q)). Here Q is an energy scale of the overall process, μ is the lepton mass and msub(q) is a hadronic mass, the effective quark mass in a parton model. The leading log radiative corrections to dsigma/dy distributions and to suitably interpreted dsigma/dx distributions are quark-mass independent. The authors improve upon the conventional leading log approximation and compute explicitly the largest terms that lie beyond the leading log level. In practice this means that the model-independent formulae, though approximate, are likely to be excellent estimates everywhere except at low energy or very large y. It is pointed out that radiative corrections to measurements of deviations from the Callan-Gross relation and to measurements of the 'sea' constituency of nucleons are gigantic. The QCD inspired study of deviations from scaling is of particular interest. The authors compute, beyond the leading log level, the radiative corrections of the QCD predictions. (Auth.)

  4. Introduction to the study of particle accelerators. Atomic, nuclear and high energy physics for engineers

    International Nuclear Information System (INIS)

    Warnecke, R.R.

    1975-01-01

    This book is destined for engineers taking part in the design building and running of nuclear physics and high-energy physics particle accelerators. It starts with some notions on the theory of relativity, analytical and statistical mechanics and quantum mechanics. An outline of the properties of atomic nuclei, the collision theory and the elements of gaseous plasma physics is followed by a discussion on elementary particles: characteristic parameters, properties, interactions, classification [fr

  5. Response of spherical gravitational wave antenna modes to high-energy cosmic ray particles

    International Nuclear Information System (INIS)

    Jr, R M Marinho; Magalhaes, N S; Aguiar, O D; Frajuca, C

    2002-01-01

    High-energy cosmic ray particles are expected to be a significant source of noise in resonant mass gravitational wave detectors close to the quantum limit. The spherical, fourth generation antennas have been designed to attain such a limit. In this work we will show how the energy of a cosmic ray particle interacting with such an antenna is distributed over its eigenmodes. We will then make some comments on the relevant consequences of such a distribution for gravitational wave detection

  6. Response of spherical gravitational wave antenna modes to high-energy cosmic ray particles

    CERN Document Server

    Marinho, R M; Aguiar, O D; Frajuca, C

    2002-01-01

    High-energy cosmic ray particles are expected to be a significant source of noise in resonant mass gravitational wave detectors close to the quantum limit. The spherical, fourth generation antennas have been designed to attain such a limit. In this work we will show how the energy of a cosmic ray particle interacting with such an antenna is distributed over its eigenmodes. We will then make some comments on the relevant consequences of such a distribution for gravitational wave detection.

  7. High-energy charged particles in space at one astronomical unit

    International Nuclear Information System (INIS)

    Feynman, J.; Gabriel, S.B.

    1996-01-01

    Single-event effects and many other spacecraft anomalies are caused by positively charged high-energy particles impinging on the vehicle and its component parts. Here, the authors review the current knowledge of the interplanetary particle environment in the energy ranges that are most important for these effects. State-of-the-art engineering models are described briefly along with comments on the future work required in this field

  8. On the high energy gamma ray spectrum and the particle production model

    International Nuclear Information System (INIS)

    Ohta, Itaru; Tezuka, Ikuo.

    1979-01-01

    A small emulsion chamber, 25 cm x 20 cm in area and 12 radiation lengths in thick, was exposed with JAL jet-cargo at an atmospheric depth of 260 g/cm 2 during 150 hrs. The gamma ray spectrum derived by combining data from X-ray films and nuclear emulsions is well represented by I sub(r) (>=Er) = (3.65 +- 0.30) x 10 -8 [E sub(r)/TeV]sup(-1.89+0.06-0.09)/cm 2 sr sec in the energy range 200 - 3,000 GeV. This result is in good agreement with those of several other groups. We discuss our data in terms of Feynman's and Koba-Nielsen-Olesen's scaling law of high energy particle production model. Interpreted in terms of an assumption of mild violation of the scaling law as x.d delta-s / delta-s indx = AE sup(2a)exp (-BE sup(a)x), our gamma ray spectrum results suggest an existence of a violation parameter of a = 0.18, which is consistent with results from gamma ray spectrum observations at great depth such as the mountain elevations. (author)

  9. Direct electron-pair production by high energy heavy charged particles

    Science.gov (United States)

    Takahashi, Y.; Gregory, J. C.; Hayashi, T.; Dong, B. L.

    1989-01-01

    Direct electron pain production via virtual photons by moving charged particles is a unique electro-magnetic process having a substantial dependence on energy. Most electro-magnetic processes, including transition radiation, cease to be sensitive to the incident energy above 10 TeV/AMU. Thus, it is expected, that upon establishment of cross section and detection efficiency of this process, it may provide a new energy measuring technique above 10 TeV/AMU. Three accelerator exposures of emulsion chambers designed for measurements of direct electron-pains were performed. The objectives of the investigation were to provide the fundamental cross-section data in emulsion stacks to find the best-fit theoretical model, and to provide a calibration of measurements of direct electron-pairs in emulsion chamber configurations. This paper reports the design of the emulsion chambers, accelerator experiments, microscope measurements, and related considerations for future improvements of the measurements, and for possible applications to high energy cosmic ray experiments. Also discussed are the results from scanning 56m of emulsion tracks at 1200x magnification so that scanning efficiency is optimized. Measurements of the delta-ray range spectrum were also performed for much shorter track lengths, but with sufficiently large statistics in the number of measured delta-rays.

  10. Overview of lunar detection of ultra-high energy particles and new plans for the SKA

    NARCIS (Netherlands)

    James, Clancy W.; Alvarez-Muñiz, Jaime; Bray, Justin D.; Buitink, Stijn; Dagkesamanskii, Rustam D.; Ekers, Ronald D.; Falcke, Heino; Gayley, Ken; Huege, Tim; Mevius, Maaijke; Mutel, Rob; Scholten, Olaf; Spencer, Ralph; ter Veen, Sander; Winchen, Tobias

    2017-01-01

    The lunar technique is a method for maximising the collection area for ultra-high-energy (UHE) cosmic ray and neutrino searches. The method uses either ground-based radio telescopes or lunar orbiters to search for Askaryan emission from particles cascading near the lunar surface. While experiments

  11. Measurement methods for high energy particle identification in gaseous mixture detectors

    International Nuclear Information System (INIS)

    Marchand, Patrick.

    1981-01-01

    In this work, we discuss some methods for high energy particle identification. We study and design a MWPC equipped with a preamplifier gap for increased resolution. In addition, we propose a new mehod of counting primary collisions. The electronic system used for multiplexing analog wire signals is also described [fr

  12. Study on the forward-feed neural network used for the classification of high energy particles

    International Nuclear Information System (INIS)

    Luo Guangxuan; Dai Guiliang

    1997-01-01

    Neural network has been applied in the field of high energy physics experiment for the classification of particles and gained good results. The author emphasizes the systematic analysis of the fundamental principle of the forward-feed neural network and discusses the problems and solving methods in application

  13. Use of high energy radiation in decomposition and removal of organic water pollutants

    International Nuclear Information System (INIS)

    Toelgyessy, P.

    1990-01-01

    The present review deals with the radiation chemistry of dilute aqueous solutions of organic substances emphasizing the possibility of use of high energy radiation in waste water treatment. Effects of radiation on biodegradability, toxicity to water organisms and changes in molecules of solutes showing resistance to biochemical degradation and toxicity to water organisms are discussed. (author) 31 refs

  14. Origin of life: hypothesized roles of high-energy electrical discharges, infrared radiation, thermosynthesis and pre-photosynthesis.

    Science.gov (United States)

    Trevors, J T

    2012-12-01

    The hypothesis is proposed that during the organization of pre-biotic bacterial cell(s), high-energy electrical discharges, infrared radiation (IR), thermosynthesis and possibly pre-photosynthesis were central to the origin of life. High-energy electrical discharges generated some simple organic molecules available for the origin of life. Infrared radiation, both incoming to the Earth and generated on the cooling Earth with day/night and warming/cooling cycles, was a component of heat engine thermosynthesis before enzymes and the genetic code were present. Eventually, a primitive forerunner of photosynthesis and the capability to capture visible light emerged. In addition, the dual particle-wave nature of light is discussed from the perspective that life requires light acting both as a wave and particle.

  15. Long-Pulse Operation and High-Energy Particle Confinement Study in ICRF Heating of LHD

    International Nuclear Information System (INIS)

    Mutoh, Takashi; Kumazawa, Ryuhei; Seki, Tetsuo

    2004-01-01

    Long-pulse operation and high-energy particle confinement properties were studied using ion cyclotron range of frequency (ICRF) heating for the Large Helical Device. For the minority-ion mode, ions with energies up to 500 keV were observed by concentrating the ICRF heating power near the plasma axis. The confinement of high-energy particles was studied using the power-modulation technique. This confirmed that the confinement of high-energy particles was better with the inward-shifted configuration than with the normal configuration. This behavior was the same for bulk plasma confinement. Long-pulse operation for more than 2 min was achieved during the experimental program in 2002. This was mainly due to better confinement of the helically trapped particles and accumulation of fewer impurities in the region of the plasma core, in conjunction with substantial hardware improvements. Currently, the plasma operation time is limited by an unexpected density rise due to outgassing from the chamber materials. The temperature of the local carbon plates of the divertor exceeded 400 deg, C, and a charge-coupled device camera observed the hot spots. The hot spot pattern was well explained by a calculation of the accelerated-particle orbits, and those accelerated particles came from outside the plasma near the ICRF antenna

  16. High energy radiation precursors to the collapse of black holes binaries based on resonating plasma modes

    Science.gov (United States)

    Coppi, B.

    2018-05-01

    The presence of well organized plasma structures around binary systems of collapsed objects [1,2] (black holes and neutron stars) is proposed in which processes can develop [3] leading to high energy electromagnetic radiation emission immediately before the binary collapse. The formulated theoretical model supporting this argument shows that resonating plasma collective modes can be excited in the relevant magnetized plasma structure. Accordingly, the collapse of the binary approaches, with the loss of angular momentum by emission of gravitational waves [2], the resonance conditions with vertically standing plasma density and magnetic field oscillations are met. Then, secondary plasma modes propagating along the magnetic field are envisioned to be sustained with mode-particle interactions producing the particle populations responsible for the observable electromagnetic radiation emission. Weak evidence for a precursor to the binary collapse reported in Ref. [2], has been offered by the Agile X-γ-ray observatory [4] while the August 17 (2017) event, identified first by the LIGO-Virgo detection of gravitational waves and featuring the inferred collapse of a neutron star binary, improves the evidence of such a precursor. A new set of experimental observations is needed to reassess the presented theory.

  17. Collective processes in a tokamak with high-energy particles: general problems of the linear theory of Alfven instabilities of a tokamak with high-energy ions

    International Nuclear Information System (INIS)

    Mikhailovskii, A.B.

    1986-01-01

    Some general problems of the theory of Alfven instabilities of a tokamak with high-energy ions are considered. It is assumed that such ions are due to either ionization of fast neutral atoms, injected into the tokamak, or production of them under thermo-nuclear conditions. Small-oscillation equations are derived for the Alfven-type waves, which allow for both destabilizing effects, associated with the high-energy particles, and stabilizing ones, such as effects of shear and bulk-plasm dissipation. A high-energy ion contribution is calculated into the growth rate of the Alfven waves. The author considers the role of trapped-electron collisional dissipation

  18. Photographic film dosimetry for high-energy accelerator radiation

    International Nuclear Information System (INIS)

    Komochkov, M.M.; Salatskaya, M.I.

    1981-01-01

    A technique for personnel photographic film dosimetry (PPFDN) of wide energy spectrum neutrons intended for measuring the effect of accelerating device radiation on personnel is described. Procedures of data measurement and processing as well as corrections to hadron contribution are presented. It is noted that the PPFDN method permits to measure a neutron dose equivalent for personnel in the range from 0.01 to 0.02 up to 100 rem, if the relativistic neutron contribution to a total dose does not exceed 5%. The upper limit of the measured dose reduced several times for a greater contribution of relativistic neutrons to the total dose [ru

  19. PAMELA’S MEASUREMENTS OF MAGNETOSPHERIC EFFECTS ON HIGH-ENERGY SOLAR PARTICLES

    Energy Technology Data Exchange (ETDEWEB)

    Adriani, O.; Bongi, M. [Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Florence (Italy); Barbarino, G. C. [Department of Physics, University of Naples “Federico II,” I-80126 Naples (Italy); Bazilevskaya, G. A. [Lebedev Physical Institute, RU-119991 Moscow (Russian Federation); Bellotti, R.; Bruno, A. [University of Bari, I-70126 Bari (Italy); Boezio, M.; Bonvicini, V.; Carbone, R. [INFN, Sezione di Trieste, I-34149 Trieste (Italy); Bogomolov, E. A. [Ioffe Physical Technical Institute, RU-194021 St. Petersburg (Russian Federation); Bottai, S. [INFN, Sezione di Florence, I-50019 Sesto Fiorentino, Florence (Italy); Bravar, U. [Space Science Center, University of New Hampshire, Durham, NH (United States); Cafagna, F. [INFN, Sezione di Bari, I-70126 Bari (Italy); Campana, D. [INFN, Sezione di Naples, I-80126 Naples (Italy); Carlson, P. [KTH, Department of Physics, and the Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre, SE-10691 Stockholm (Sweden); Casolino, M.; De Donato, C. [INFN, Sezione di Rome “Tor Vergata,” I-00133 Rome (Italy); Castellini, G. [IFAC, I-50019 Sesto Fiorentino, Florence (Italy); Christian, E. R.; Nolfo, G. A. de, E-mail: georgia.a.denolfo@nasa.gov [Heliophysics Division, NASA Goddard Space Flight Center, Greenbelt, MD (United States); and others

    2015-03-01

    The nature of particle acceleration at the Sun, whether through flare reconnection processes or through shocks driven by coronal mass ejections, is still under scrutiny despite decades of research. The measured properties of solar energetic particles (SEPs) have long been modeled in different particle-acceleration scenarios. The challenge has been to disentangle the effects of transport from those of acceleration. The Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) instrument enables unique observations of SEPs including the composition and angular distribution of the particles about the magnetic field, i.e., pitch angle distribution, over a broad energy range (>80 MeV)—bridging a critical gap between space-based and ground-based measurements. We present high-energy SEP data from PAMELA acquired during the 2012 May 17 SEP event. These data exhibit differential anisotropies and thus transport features over the instrument rigidity range. SEP protons exhibit two distinct pitch angle distributions: a low-energy population that extends to 90° and a population that is beamed at high energies (>1 GeV), consistent with neutron monitor measurements. To explain a low-energy SEP population that exhibits significant scattering or redistribution accompanied by a high-energy population that reaches the Earth relatively unaffected by dispersive transport effects, we postulate that the scattering or redistribution takes place locally. We believe that these are the first comprehensive measurements of the effects of solar energetic particle transport in the Earth’s magnetosheath.

  20. Interaction of Repetitively Pulsed High Energy Laser Radiation With Matter

    Science.gov (United States)

    Hugenschmidt, Manfred

    1986-10-01

    The paper is concerned with laser target interaction processes involving new methods of improving the overall energy balance. As expected theoretically, this can be achieved with high repetition rate pulsed lasers even for initially highly reflecting materials, such as metals. Experiments were performed by using a pulsed CO2 laser at mean powers up to 2 kW and repetition rates up to 100 Hz. The rates of temperature rise of aluminium for example were thereby increased by lore than a factor of 3 as compared to cw-radiation of comparable power density. Similar improvements were found for the overall absorptivities that were increased by this method by more than an order of magnitude.

  1. Radiation in Particle Simulations

    International Nuclear Information System (INIS)

    More, R.; Graziani, F.; Glosli, J.; Surh, M.

    2010-01-01

    Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of megabars to thousands of gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present four methods that attempt a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The first method applies the Lienard-Weichert solution of Maxwell's equations for a classical particle whose motion is assumed to be known. The second method expands the electromagnetic field in normal modes (planewaves in a box with periodic boundary-conditions) and solves the equation for wave amplitudes coupled to the particle motion. The third method is a hybrid molecular dynamics/Monte Carlo (MD/MC) method which calculates radiation emitted or absorbed by electron-ion pairs during close collisions. The fourth method is a generalization of the third method to include small clusters of particles emitting radiation during close encounters: one electron simultaneously hitting two ions, two electrons simultaneously hitting one ion, etc. This approach is inspired by the virial expansion method of equilibrium statistical mechanics. Using a combination of these methods we believe it is possible to do atomic-scale particle simulations of

  2. Radiation Fields in High Energy Accelerators and their impact on Single Event Effects

    CERN Document Server

    García Alía, Rubén; Wrobel, Frédéric; Brugger, Markus

    Including calculation models and measurements for a variety of electronic components and their concerned radiation environments, this thesis describes the complex radiation field present in the surrounding of a high-energy hadron accelerator and assesses the risks related to it in terms of Single Event Effects (SEE). It is shown that this poses not only a serious threat to the respective operation of modern accelerators but also highlights the impact on other high-energy radiation environments such as those for ground and avionics applications. Different LHC-like radiation environments are described in terms of their hadron composition and energy spectra. They are compared with other environments relevant for electronic component operation such as the ground-level, avionics or proton belt. The main characteristic of the high-energy accelerator radiation field is its mixed nature, both in terms of hadron types and energy interval. The threat to electronics ranges from neutrons of thermal energies to GeV hadron...

  3. High-energy ionizing radiation initiated decomposition of acetovanillone

    International Nuclear Information System (INIS)

    Gonter, K.; Takacs, E.; Wojnarovits, L.

    2011-01-01

    Complete text of publication follows. Acetovanillone (AV) i.e.g 1-(4-hydroxy-3-methoxyphenyl)ethanone) with other name Apocynin, a derivative of vanillin, is known for its anti-inflammatory capabilities which is attributed to its radical scavenging ability. AV is one of the main phenolyc pollutants which is present in the wastewater produced during the boiling process in cork industry. It is a biorecalcitrant compound which blocks the biodegradation. Advanced oxidation processes, among them irradiation induced degradation may help to solve this problem. As the experiments show AV readily degrades under the effect of ionizing radiation; at a concentration of 0.1 mmol dm -3 a dose of 5 kGy is sufficient for complete degradation of AV and its main decomposition products. In neutral solution the · OH radicals take part in radical addition reaction to the aromatic ring with a diffusion limited rate coefficient. In the reaction hydroxycyclohexadienyl type radical forms. This radical within a c.a. 15 μs transforms to phenoxy radical. The phenoxy radical decays on the ms timescale. These intermediates are characterised and a degradation mechanism is suggested.

  4. Control of the radiation environment and the worker in high-energy facilities

    International Nuclear Information System (INIS)

    Stevenson, G.R.

    1993-01-01

    The philosophy behind the prediction, measurement, monitoring and limitation by access control of the radiation hazard in high-energy accelerator facilities is compared with that which could be employed for controlling similar hazards due to cosmic radiation in civil aircraft flights. Special mention is made of computer simulations of the radiation environment as a means of predicting necessary control measures, of the reliability and integration of radiation measuring devices into control procedures and of the relevance of different access control procedures. (author)

  5. Radiation damage in silicon exposed to high-energy protons

    International Nuclear Information System (INIS)

    Davies, Gordon; Hayama, Shusaku; Murin, Leonid; Krause-Rehberg, Reinhard; Bondarenko, Vladimir; Sengupta, Asmita; Davia, Cinzia; Karpenko, Anna

    2006-01-01

    Photoluminescence, infrared absorption, positron annihilation, and deep-level transient spectroscopy (DLTS) have been used to investigate the radiation damage produced by 24 GeV/c protons in crystalline silicon. The irradiation doses and the concentrations of carbon and oxygen in the samples have been chosen to monitor the mobility of the damage products. Single vacancies (and self-interstitials) are introduced at the rate of ∼1 cm -1 , and divacancies at 0.5 cm -1 . Stable di-interstitials are formed when two self-interstitials are displaced in one damage event, and they are mobile at room temperature. In the initial stages of annealing the evolution of the point defects can be understood mainly in terms of trapping at the impurities. However, the positron signal shows that about two orders of magnitude more vacancies are produced by the protons than are detected in the point defects. Damage clusters exist, and are largely removed by annealing at 700 to 800 K, when there is an associated loss of broad band emission between 850 and 1000 meV. The well-known W center is generated by restructuring within clusters, with a range of activation energies of about 1.3 to 1.6 eV, reflecting the disordered nature of the clusters. Comparison of the formation of the X centers in oxygenated and oxygen-lean samples suggests that the J defect may be interstitial related rather than vacancy related. To a large extent, the damage and annealing behavior may be factorized into point defects (monitored by sharp-line optical spectra and DLTS) and cluster defects (monitored by positron annihilation and broadband luminescence). Taking this view to the limit, the generation rates for the point defects are as predicted by simply taking the damage generated by the Coulomb interaction of the protons and Si nuclei

  6. Radiation effects on semiconductor devices in high energy heavy ion accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Belousov, Anton

    2014-10-20

    Radiation effects on semiconductor devices in GSI Helmholtz Center for Heavy Ion Research are becoming more and more significant with the increase of beam intensity due to upgrades. Moreover a new accelerator is being constructed on the basis of GSI within the project of facility for antiproton and ion research (FAIR). Beam intensities will be increased by factor of 100 and energies by factor of 10. Radiation fields in the vicinity of beam lines will increase more than 2 orders of magnitude and so will the effects on semiconductor devices. It is necessary to carry out a study of radiation effects on semiconductor devices considering specific properties of radiation typical for high energy heavy ion accelerators. Radiation effects on electronics in accelerator environment may be divided into two categories: short-term temporary effects and long-term permanent degradation. Both may become critical for proper operation of some electronic devices. This study is focused on radiation damage to CCD cameras in radiation environment of heavy ion accelerator. Series of experiments with irradiation of devices under test (DUTs) by secondary particles produced during ion beam losses were done for this study. Monte Carlo calculations were performed to simulate the experiment conditions and conditions expected in future accelerator. Corresponding comparisons and conclusions were done. Another device typical for accelerator facilities - industrial Ethernet switch was tested in similar conditions during this study. Series of direct irradiations of CCD and MOS transistors with heavy ion beams were done as well. Typical energies of the primary ion beams were 0.5-1 GeV/u. Ion species: from Na to U. Intensities of the beam up to 10{sup 9} ions/spill with spill length of 200-300 ns. Criteria of reliability and lifetime of DUTs in specific radiation conditions were formulated, basing on experimental results of the study. Predictions of electronic device reliability and lifetime were

  7. Complex workplace radiation fields at European high-energy accelerators and thermonuclear fusion facilities

    CERN Document Server

    Bilski, P; D'Errico, F; Esposito, A; Fehrenbacher, G; Fernàndez, F; Fuchs, A; Golnik, N; Lacoste, V; Leuschner, A; Sandri, S; Silari, M; Spurny, F; Wiegel, B; Wright, P

    2006-01-01

    This report outlines the research needs and research activities within Europe to develop new and improved methods and techniques for the characterization of complex radiation fields at workplaces around high-energy accelerators and the next generation of thermonuclear fusion facilities under the auspices of the COordinated Network for RAdiation Dosimetry (CONRAD) project funded by the European Commission.

  8. Cryogenics for high-energy particle accelerators: highlights from the first fifty years

    CERN Document Server

    AUTHOR|(CDS)2067931

    2017-01-01

    Applied superconductivity has become a key technology for high-energy particle accelerators, allowing to reach higher beam energy while containing size, capital expenditure and operating costs. Large and powerful cryogenic systems are therefore ancillary to low-temperature superconducting accelerator devices – magnets and high-frequency cavities – distributed over multi-kilometre distances and operating generally close to the normal boiling point of helium, but also above 4.2 K in supercritical and down to below 2 K in superfluid. Additionally, low-temperature operation in accelerators may also be required by considerations of ultra-high vacuum, limited stored energy and beam stability. We discuss the rationale for cryogenics in high-energy particle accelerators, review its development over the past half-century and present its outlook in future large projects, with reference to the main engineering domains of cryostat design and heat loads, cooling schemes, efficient power refrigeration and cryogenic flu...

  9. Feigenbaum scenario for turbulence and Cantorian E-infinity theory of high energy particle physics

    International Nuclear Information System (INIS)

    El Naschie, M.S.

    2007-01-01

    The work draws some fundamental connections between Feigenbaum's golden mean renormalization group and scenario for turbulence on the one side and high energy particle physics on the other side. The analysis which is based on the natural and obvious connections between the Fibonacci-like geometrical growth rate of ε (∞) spacetime and Feigenbaum's renormalization gives vital information to basic questions not only of quantum geometry, but also of quantum field theory

  10. Shocks from high-energy nuclear-interacting particles in the mountain Chakaltajya

    Energy Technology Data Exchange (ETDEWEB)

    Kamata, K [Tokyo Univ. (Japan)

    1975-06-01

    Experimental investigations of extensive air showers at the height of 5200 m above the sea level have been performed. The behaviour of high energy nuclear active particles in the cores of the showers has been studied using the nuclear knock-on method. The cross section of the proton inelastic interaction with the air is shown to increase with energy in the energy range of 3-9 TeV.

  11. HIGH-ENERGY PARTICLES FLUX ORIGIN IN THE CLOUDS, DARK LIGHTNING

    Directory of Open Access Journals (Sweden)

    Kuznetsov, V.V.

    2016-11-01

    Full Text Available Problem of high-energy particles flux origin in clouds is discussed. Conditions in which dark lightning preceding the ordinary one and creating additional ionization, fluxes of fast electrons with MeV energy prior to the earthquake detected among lightning initiating ball-lightning, glow, sprites are considered. All above phenomena appear to be of general nature founded on quantum entanglement of hydrogen bonds protons in water clasters inside clouds.

  12. Intercomparison of radiation protection devices in a high-energy stray neutron field. Part III: Instrument response

    CERN Document Server

    Silari, M; Beck, P; Bedogni, R; Cale, E; Caresana, M; Domingo, C; Donadille, L; Dubourg, N; Esposito, A; Fehrenbacher, G; Fernández, F; Ferrarini, M; Fiechtner, A; Fuchs, A; García, M J; Golnik, N; Gutermuth, F; Khurana, S; Klages, Th; Latocha, M; Mares, V; Mayer, S; Radon, T; Reithmeier, H; Rollet, S; Roos, H; Rühm, W; Sandri, S; Schardt, D; Simmer, G; Spurný, F; Trompier, F; Villa-Grasa, C; Weitzenegger, E; Wiegel, B; Wielunski, M; Wissmann, F; Zechner, A; Zielczyński, M

    2009-01-01

    The European Commission has funded within its 6th Framework Programme a three-year project (2005–2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organizational framework for this project was provided by the European radiation Dosimetry Group EURADOS. Work Package 6 of CONRAD dealt with “complex mixed radiation fields at workplaces” and in this context it organised a benchmark exercise, which included both measurements and calculations, in a stray radiation field at a high-energy particle accelerator at GSI, Germany. The aim was to intercompare the response of several types of active detectors and passive dosemeters in a well-characterised workplace field. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers are discussed in Rollet et al. (2008) and in Wiegel et al. (2008). This paper focuses on the intercomparison of the response of the dosemeters in terms of ambient dose equivalent. Th...

  13. Gas-liquid transition in the model of particles interacting at high energy

    International Nuclear Information System (INIS)

    Bondarenko, S.; Komoshvili, K.

    2013-01-01

    An application of the ideas of the inertial confinement fusion process in the case of particles interacting at high energy is investigated. A possibility of the gas-liquid transition in the gas is considered using different approaches. In particular, a shock wave description of interactions between particles is studied and a self-similar solution of Euler's equation is discussed. Additionally, the Boltzmann equation is solved for a self-consistent field (Vlasov's equation) in the linear approximation for the case of a gas under external pressure and the corresponding change of the Knudsen number of the system is calculated. (orig.)

  14. [High energy particle physics]: Task A, High energy physics program: Experiment and theory; Task B, High energy physics program: Numerical simulation of quantum field theories

    International Nuclear Information System (INIS)

    Lannutti, J.E.

    1991-01-01

    This report discusses the following research: fixed target experiments; collider experiments; computing, networking and VAX upgrade; SSC preparation, detector development and detector construction; solid argon calorimetry; absorption of CAD system geometries into GEANT for SSC; and particle theory programs

  15. An investigation of fission models for high-energy radiation transport calculations

    International Nuclear Information System (INIS)

    Armstrong, T.W.; Cloth, P.; Filges, D.; Neef, R.D.

    1983-07-01

    An investigation of high-energy fission models for use in the HETC code has been made. The validation work has been directed checking the accuracy of the high-energy radiation transport computer code HETC to investigate the appropriate model for routine calculations, particularly for spallation neutron source applications. Model calculations are given in terms of neutron production, fission fragment energy release, and residual nuclei production for high-energy protons incident on thin uranium targets. The effect of the fission models on neutron production from thick uranium targets is also shown. (orig.)

  16. DYNECHARM++: a toolkit to simulate coherent interactions of high-energy charged particles in complex structures

    Science.gov (United States)

    Bagli, Enrico; Guidi, Vincenzo

    2013-08-01

    A toolkit for the simulation of coherent interactions between high-energy charged particles and complex crystal structures, called DYNECHARM++ has been developed. The code has been written in C++ language taking advantage of this object-oriented programing method. The code is capable to evaluating the electrical characteristics of complex atomic structures and to simulate and track the particle trajectory within them. Calculation method of electrical characteristics based on their expansion in Fourier series has been adopted. Two different approaches to simulate the interaction have been adopted, relying on the full integration of particle trajectories under the continuum potential approximation and on the definition of cross-sections of coherent processes. Finally, the code has proved to reproduce experimental results and to simulate interaction of charged particles with complex structures.

  17. The effects of high energy radiation on the pulping properties of Pinus radiation and Eucalyptus regnans

    International Nuclear Information System (INIS)

    McLaren, K.G.; Garland, C.P.; Higgins, H.G.

    1976-01-01

    Studies have been made of the effects of high energy radiation on the pulping behaviour of Eucalyptus regnans and Pinus radiata. Pre-irradiation of wood chips with small doses of 60 Co gamma radiation (up to about 0.2 Mrad) caused little degradation of the cellulose, and had only minor effects on the kraft pulping properties of both wood species. Pulp yield, Kappa number and strength properties of the pulps showed little change. There was also little effect on the bisulphite cooking of Pinus radiata. As the dose was increased to 1 Mrad, degradation of cellulose (as indicated by degree of polymerisation measurements) became significant, and Kraft pulp yields from both woods showed small reductions. The Kappa number and physical properties of these pulps were little affected at this dose level. A gamma radiation dose of 10 Mrad produced marked depolymerisation of the cellulose, and big reductions in kraft and neutral sulphite semi-chemical pulp yields. The kraft pulps showed a much higher lignin content. Some low dose (0.15 Mrad) irradiations on thin chips were carried out with a 1 MeV electron accelerator. In contrast to comparable gamma irradiations, this treatment produced discernible changes in kraft pulping behaviour. The pulp yield, under the same cooking conditions, appears to be slightly higher, but the Lignin content of the pulp was increased. (Author)

  18. Solving radiation problems at particle accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Nikolai V. Mokhov

    2001-12-11

    At high-intensity high-energy particle accelerators, consequences of a beam-induced radiation impact on machine and detector components, people, environment and complex performance can range from negligible to severe. The specifics, general approach and tools used at such machines for radiation analysis are described. In particular, the world leader Fermilab accelerator complex is considered, with its fixed target and collider experiments, as well as new challenging projects such as LHC, VLHC, muon collider and neutrino factory. The emphasis is on mitigation of deleterious beam-induced radiation effects and on the key role of effective computer simulations.

  19. Solving radiation problems at particle accelerators

    International Nuclear Information System (INIS)

    Mokhov, N.V.

    2001-01-01

    At high-intensity high-energy particle accelerators, consequences of a beam-induced radiation impact on machine and detector components, people, environment and complex performance can range from negligible to severe. The specifics, general approach and tools used at such machines for radiation analysis are described. In particular, the world leader Fermilab accelerator complex is considered, with its fixed target and collider experiments, as well as new challenging projects such as LHC, VLHC, muon collider and neutrino factory. The emphasis is on mitigation of deleterious beam-induced radiation effects and on the key role of effective computer simulations

  20. Production and supply of radioisotopes with high-energy particle accelerators current status and future directions

    International Nuclear Information System (INIS)

    Srivastava, S.C.; Mausner, L.F.

    1994-01-01

    Although the production of radioisotopes in reactors or in low to medium energy cyclotrons appears to be relatively well established, especially for those isotopes that are routinely used and have a commercial market, certain isotopes can either be made only in high-energy particle accelerators or their production is more cost effective when made this way. These facilities are extremely expensive to build and operate, and isotope production is, in general, either not cost-effective or is in conflict with their primary mandate or missions which involve physics research. Isotope production using high-energy accelerators in the US, therefore, has been only an intermittent and parasitic activity. However, since a number of isotopes produced at higher energies are emerging as being potentially useful for medical and other applications, there is a renewed concern about their availability in a continuous and reliable fashion. In the US, in particular, the various aspects of the prediction and availability of radioisotopes from high-energy accelerators are presently undergoing a detailed scrutiny and review by various scientific and professional organizations as well as the Government. A number of new factors has complicated the supply/demand equation. These include considerations of cost versus needs, reliability factors, mission orientation, research and educational components, and commercial viability. This paper will focus on the present status and projected needs of radioisotope production with high-energy accelerators in the US, and will compare and examine the existing infrastructure in other countries for this purpose

  1. Study of particle size distribution and formation mechanism of radioactive aerosols generated in high-energy neutron fields

    CERN Document Server

    Endo, A; Noguchi, H; Tanaka, S; Iida, T; Furuichi, S; Kanda, Y; Oki, Y

    2003-01-01

    The size distributions of sup 3 sup 8 Cl, sup 3 sup 9 Cl, sup 8 sup 2 Br and sup 8 sup 4 Br aerosols generated by irradiations of argon and krypton gases containing di-octyl phthalate (DOP) aerosols with 45 MeV and 65 MeV quasi-monoenergetic neutrons were measured in order to study the formation mechanism of radioactive particles in high energy radiation fields. The effects of the size distribution of the radioactive aerosols on the size of the added DOP aerosols, the energy of the neutrons and the kinds of nuclides were studied. The observed size distributions of the radioactive particles were explained by attachment of the radioactive atoms generated by the neutron-induced reactions to the DOP aerosols. (author)

  2. Development of High Energy Particle Detector for the Study of Space Storms onboard Next Generation Small Satellite-1

    Science.gov (United States)

    Sohn, J. D.; Min, K.; Lee, J.; Lee, D. Y.; Yi, Y.; Kang, K.; Shin, G. H.; Jo, G. B.; Lee, S. U.; Na, G.

    2017-12-01

    We reports the development of the High Energy Particle Detector (HEPD), one of the radiation detectors on board the Next Generation Small Satellite-1 to be launched into a low-Earth polar orbit in late 2017. The HEPD consists of three telescopes, each with a field of view of 33.4°, that are mounted on the satellite to have an angle of 0°, 45°, and 90° to the geomagnetic field during observations in the Earth's sub-auroral regions. The detection system of each telescope is composed of two silicon surface barrier detectors (SSDs), with the capability of measuring electrons from 300 keV to 2 MeV at 32 Hz that precipitate into the polar regions from the Earth's radiation belts when space storms occur. The successful operation of the HEPD in orbit will help us understand the interaction mechanisms between energetic electrons and plasma waves such as whistler and Electromagnetic Ion Cyclotron (EMIC) waves that are believed to be responsible for the energization and loss of high energy electrons in the Earth's radiation belts.

  3. Application of the non-extensive statistical approach to high energy particle collisions

    Science.gov (United States)

    Bíró, Gábor; Barnaföldi, Gergely Gábor; Biró, Tamás Sándor; Ürmössy, Károly

    2017-06-01

    In high-energy collisions the number of created particles is far less than the thermodynamic limit, especially in small colliding systems (e.g. proton-proton). Therefore final-state effects and fluctuations in the one-particle energy distribution are appreciable. As a consequence the characterization of identified hadron spectra with the Boltzmann - Gibbs thermodynamical approach is insuffcient [1]. Instead particle spectra measured in high-energy collisions can be described very well with Tsallis -Pareto distributions, derived from non-extensive thermodynamics [2, 3]. Using the Tsallis q-entropy formula, a generalization of the Boltzmann - Gibbs entropy, we interpret the microscopic physics by analysing the Tsallis q and T parameters. In this paper we give a quick overview on these parameters, analyzing identified hadron spectra from recent years in a wide center-of-mass energy range. We demonstrate that the fitted Tsallis-parameters show dependency on the center-of-mass energy and particle species. Our findings are described well by a QCD inspired evolution ansatz. Based on this comprehensive study, apart from the evolution, both mesonic and barionic components found to be non-extensive (q > 1), beside the mass ordered hierarchy observed in parameter T.

  4. Particle damage sources for fused silica optics and their mitigation on high energy laser systems.

    Science.gov (United States)

    Bude, J; Carr, C W; Miller, P E; Parham, T; Whitman, P; Monticelli, M; Raman, R; Cross, D; Welday, B; Ravizza, F; Suratwala, T; Davis, J; Fischer, M; Hawley, R; Lee, H; Matthews, M; Norton, M; Nostrand, M; VanBlarcom, D; Sommer, S

    2017-05-15

    High energy laser systems are ultimately limited by laser-induced damage to their critical components. This is especially true of damage to critical fused silica optics, which grows rapidly upon exposure to additional laser pulses. Much progress has been made in eliminating damage precursors in as-processed fused silica optics (the advanced mitigation process, AMP3), and very high damage resistance has been demonstrated in laboratory studies. However, the full potential of these improvements has not yet been realized in actual laser systems. In this work, we explore the importance of additional damage sources-in particular, particle contamination-for fused silica optics fielded in a high-performance laser environment, the National Ignition Facility (NIF) laser system. We demonstrate that the most dangerous sources of particle contamination in a system-level environment are laser-driven particle sources. In the specific case of the NIF laser, we have identified the two important particle sources which account for nearly all the damage observed on AMP3 optics during full laser operation and present mitigations for these particle sources. Finally, with the elimination of these laser-driven particle sources, we demonstrate essentially damage free operation of AMP3 fused silica for ten large optics (a total of 12,000 cm 2 of beam area) for shots from 8.6 J/cm 2 to 9.5 J/cm 2 of 351 nm light (3 ns Gaussian pulse shapes). Potentially many other pulsed high energy laser systems have similar particle sources, and given the insight provided by this study, their identification and elimination should be possible. The mitigations demonstrated here are currently being employed for all large UV silica optics on the National Ignition Facility.

  5. LET spectrometry with track etch detectors-Use in high-energy radiation fields

    International Nuclear Information System (INIS)

    Jadrnickova, I.; Spurny, F.

    2008-01-01

    For assessing the risk from ionizing radiation it is necessary to know not only the absorbed dose but also the quality of the radiation; radiation quality is connected with the physical quantity linear energy transfer (LET). One of the methods of determination of LET is based on chemically etched track detectors. This contribution concerns with a spectrometer of LET based on the track detectors and discusses some results obtained at: ·high-energy radiation reference field created at the SPS accelerator at CERN; and ·onboard of International Space Station where track-etch based LET spectrometer has been exposed 273 days during 'Matrjoshka - R' experiment. Results obtained are compared with the results of studies at some lower-energy neutron sources; some conclusions on the registrability of neutrons and the ability of this spectrometer to determine dose equivalent in high-energy radiation fields are formulated

  6. Studying the high energy cosmic radiation: contributions to its detection and to the exploration of its origin

    International Nuclear Information System (INIS)

    Lamanna, Giovanni

    2009-01-01

    The Astro-particle Physics is a discipline where scientists from both the astrophysics and the particle physics communities meets to investigate the Universe aiming to answer to fundamental questions in the field of physics, cosmology and astrophysics. The high energy astrophysics domain, which explores the extremes sources where the larger collective transfer of energy take place, studies the most energetic cosmic radiation as privileged messengers of the history of the Universe. My research path, summarized in this work, is made of personal contributions in the development of new detection technologies, in the data analysis, perspectives and phenomenological studies about the scientific purposes of large experiments: e.g. AMS, ANTARES, HESS, CTA, POLAR. My contributions are the results of research activities in coherence with two main scientific goals in the context of the astro-particle physics domain: - The implication of the high energy cosmic radiation measurement for the investigation on the nature and distribution of the dark matter; - The investigation of the origin of the galactic cosmic radiation for the understanding of the most energetic processes in the Universe. (author)

  7. Radiation protection challenges in the management of radioactive waste from high-energy accelerators.

    Science.gov (United States)

    Ulrici, Luisa; Algoet, Yvon; Bruno, Luca; Magistris, Matteo

    2015-04-01

    The European Laboratory for Particle Physics (CERN) has operated high-energy accelerators for fundamental physics research for nearly 60 y. The side-product of this activity is the radioactive waste, which is mainly generated as a result of preventive and corrective maintenance, upgrading activities and the dismantling of experiments or accelerator facilities. Prior to treatment and disposal, it is common practice to temporarily store radioactive waste on CERN's premises and it is a legal requirement that these storage facilities are safe and secure. Waste treatment typically includes sorting, segregation, volume and size reduction and packaging, which will depend on the type of component, its chemical composition, residual activity and possible surface contamination. At CERN, these activities are performed in a dedicated waste treatment centre under the supervision of the Radiation Protection Group. This paper gives an overview of the radiation protection challenges in the conception of a temporary storage and treatment centre for radioactive waste in an accelerator facility, based on the experience gained at CERN. The CERN approach consists of the classification of waste items into 'families' with similar radiological and physical-chemical properties. This classification allows the use of specific, family-dependent techniques for radiological characterisation and treatment, which are simultaneously efficient and compliant with best practices in radiation protection. The storage was planned on the basis of radiological and other possible hazards such as toxicity, pollution and fire load. Examples are given of technical choices for the treatment and radiological characterisation of selected waste families, which could be of interest to other accelerator facilities. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Configuration of particle drain for the high energy charged particles in the magnetic dipole field

    International Nuclear Information System (INIS)

    Amirkhanov, I.V.; Zhidkov, E.P.; Ignatov, V.V.; Il'ina, A.N.; Il'in, V.D.; Kuznetsov, S.N.; Yushkov, B.Yu.

    1987-01-01

    The boundary of particle leakage from the magnetic dipole trap depending on the value of adiabatic parameter is investigated. By trajectory computation a generalized analytical expression is determined for the shape of particle drain by x ≤ 1. It is shown that generally accepted adiabatic loss cone is a particular case of x → 0

  9. Axion-like particles: possible hints and constraints from the high-energy Universe

    International Nuclear Information System (INIS)

    Brun, Pierre

    2013-01-01

    The high-energy Universe is potentially a great laboratory for searching new light bosons such as axion-like particles (ALPs). Cosmic sources are indeed the scene of violent phenomena that involve strong magnetic field and/or very long baselines, where the effects of the mixing of photons with ALPs could lead to observable effects. Two examples are archetypal of this fact, that are the Universe opacity to gamma-rays and the imprints of astrophysical magnetic turbulence in the energy spectra of high-energy sources. In the first case, hints for the existence of ALPs can be proposed whereas the second one is used to put constraints on the ALP mass and coupling to photons

  10. Production and supply of radioisotopes with high-energy particle accelerators current status and future directions

    International Nuclear Information System (INIS)

    Srivastava, S.C.; Mausner, L.F.

    1994-01-01

    Although the production of radioisotopes in reactors or in low to medium energy cyclotrons appears to be relatively well established, certain isotopes can either be made only in high-energy particle accelerators or their production is more cost effective when made this way. These facilities are extremely expensive to build and operate, and isotope production is, in general, either not cost-effective or is in conflict with their primary mandate or missions which involve physics research. Isotope production using high-energy accelerators in the U.S., therefore, has been only an intermittent and parasitic activity. However, since a number of isotopes produced at higher energies are emerging as being potentially useful for medical and other applications, there is a renewed concern about their availability in a continuous and reliable fashion. In the U.S., in particular, the various aspects of the production and availability of radioisotopes from high-energy accelerators are presently undergoing a detailed scrutiny and review by various scientific and professional organizations as well as the Government. A number of new factors has complicated the supply/demand equation. These include considerations of cost versus needs, reliability factors, mission orientation, research and educational components, and commercial viability. This paper will focus on the present status and projected needs of radioisotope production with high-energy accelerators in the U.S., and will compare and examine the existing infrastructure in other countries for this purpose. The nature of the U.S. decisions to address many of the above-mentioned issues and an eventual plan of attack to resolve them are bound to have a world-wide impact in the radioisotope user communities. These will be discussed with a view to evaluating the best possible solutions in order to eliminate the shortage in the future supply of radioisotopes produced in high energy accelerators. (author)

  11. Study of a charge-coupled device for high-energy-particle detection

    International Nuclear Information System (INIS)

    Bhuiya, A.H.

    1983-05-01

    This presentation is based on measurements made to evaluate the application of charge-coupled devices as detectors of high-energy particles. The experiment was performed with a Fairchild Linear 256-Cell CCD111 array (size 8μm x 17 μm/cell), utilizing a light source instead of a particle beam. It was observed that the minimum detectable signal was limited to approx. 488 electrons at -50 0 C, where the readout and exposure times were about 260 ms and 400 ms respectively. The transfer inefficiency of the CCD111 was determined to be approx. 10 -4 . It has been concluded that at a lower temperature (approx. -100 0 C) or with faster readout (approx. 10 ms), the CCD111 would be able to detect the total deposited energy of minimum-ionizing charged particles

  12. Hands on CERN an education project on the Internet using real high energy particle collisions

    CERN Document Server

    Johansson, E K

    1999-01-01

    An educational project primarily aimed at teachers and 15 to 18 year- old students describing the essential features of a modern high energy physics experiment has been created. The whole education package is available on the Internet. It gives a detailed description of the physics processes involved and the Standard Model of Microcosm. Real particle collisions produced with the facilities at the European particle physics laboratory (CERN) are displayed using the platform-independent programming language Java, enabling interaction with the user. The project has been used by several groups of teachers and students, and has increased their knowledge of, and interest in, particle physics. This project complements the traditional physics education and introduces students to contemporary fundamental physics. (7 refs).

  13. A high energy photon beam derived from neutral strange particle decay

    International Nuclear Information System (INIS)

    Reibel, K.; Ruchti, R.

    1982-01-01

    Conventional methods for generating photon beams include: tagged beams in which the photons are derived from electron bremsstrahlung in a radiator target; and broad band beams in which the photons are derived from π/sup 0/ decay - the hadronic component (n, K/sub s//sup 0/) accompanying such a beam is usually suppressed by passage of the beam through a low Z (D/sub 2/) filter. Although one can generate high energy photons by these techniques, the major drawback to these beams is that the photon energy spectrum obtained is peaked at very low E/sub γ/. (Recall that the bremsstrahlung spectrum falls as 1/k). With very high energy proton beams (20 TeV/c), one can image other alternatives for photon beam design. The authors consider one such option here

  14. Current problems in semiconductor detectors for high energy physics after particle irradiations

    International Nuclear Information System (INIS)

    Lazanu, Ionel

    2002-01-01

    The use of semiconductor materials as detectors in high radiation environments, as expected in future high energy accelerators or in space missions, poses severe problems in long-time operations, due to changes in the properties of the material, and consequently in the performances of detectors. This talk presents the major theoretical areas of current problems, reviews the works in this field and the stage of their understanding, including author's contributions The mechanisms of interaction of the projectile with the semiconductor, the production of primary defects, the physical quantities and the equations able to characterise and describe the radiation effects, and the equations of kinetics of defects are considered. Correlation between microscopic damage and detector performances and the possible ways to optimise the radiation hardness of materials are discussed. (author)

  15. Probing the stability of superheavy dark matter particles with high-energy neutrinos

    International Nuclear Information System (INIS)

    Esmaili, Arman; Peres, O.L.G.

    2012-01-01

    Full text: There is currently mounting evidence for the existence of dark matter in our Universe from various astrophysical and cosmological observations, but the two of the most fundamental properties of the dark matter particle, the mass and the lifetime, are only weakly constrained by the astronomical and cosmological evidence of dark matter. We derive lower limits on the lifetime of dark matter particles with masses in the range 10 TeV - 10 18 GeV from the non-observation of ultrahigh energy neutrinos in the AMANDA, IceCube, Auger and ANITA experiments. All these experiments probe different energy windows and perfectly complement each other. For dark matter particles which produce neutrinos in a two body or a three body decay, we find that the dark matter lifetime must be longer than ∼ 10 26 s for masses between 10 TeV and the Grand Unification scale. We will consider various scenarios where the decay of the dark matter particle produces high energy neutrinos. Neutrinos travel in the Universe without suffering an appreciable attenuation, even for EeV neutrinos, in contrast to photons which rapidly lose their energy via pair production. This remarkable property makes neutrinos a very suitable messenger to constrain the lifetime of superheavy dark matter particles. Finally, we also calculate, for concrete particle physics scenarios, the limits on the strength of the interactions that induce the dark matter decay. (author)

  16. Searching for squeezed particle-antiparticle correlations in high-energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Padula, Sandra S.; Socolowski, O. Jr.

    2010-01-01

    Squeezed correlations of particle-antiparticle pairs were predicted to exist if the hadron masses were modified in the hot and dense medium formed in high-energy heavy-ion collisions. Although well-established theoretically, they have not yet been observed experimentally. We suggest here a clear method to search for such a signal by analyzing the squeezed correlation functions in terms of measurable quantities. We illustrate this suggestion for simulated φφ pairs at the Relativistic Heavy Ion Collider (RHIC) energies.

  17. New directions in elementary particle physics: p anti p from very low to very high energies

    International Nuclear Information System (INIS)

    Jacob, M.

    1979-01-01

    The review covers low energy anti pp physics including annihilation processes, the spectroscopy of baryonium states, quasinuclear states and their relation to baryonium, the spectroscopy of protonium, and access to the whole charmonium family. High energy anti pp physics is reviewed covering total cross section rise, the common shape of cross sections, real part of forward amplitude, particle production, quantum number excitation, high transverse momentum, and high mass lepton pair. Also reviewed are the search for the weak bosons, hadron physics at collider energies, and the anti pp collider program. 47 references

  18. Neural nets with varying topology for high energy particle recognition. Theory and applications

    International Nuclear Information System (INIS)

    Perrone, A.L.; Basti, G.; Messi, R.; Paoluzi, L.; Picozza, P.

    1995-01-01

    In this paper we propose a strategy to solve the problem of parallel compuation based on a dynamic definition of the net topology showing its effectiveness for problems of particle track recognition in high-energy physics. In this way, we can maintain the linear architecture like in the geometric perceptron, but with a partial and dynamic connectivity so to overcome the intrinsic limiations of the geometric perceptron. Namely, the computation is truly parallel because of the partial connectivity but the net topology is always the optimal one because of its dynamic redefinition on the single input pattern. For these properties, we call this new architecture dynamic perceptron

  19. Particle production in high energy nucleus--nucleus experiments at Berkeley

    International Nuclear Information System (INIS)

    Schroeder, L.S.

    1976-09-01

    A review of high energy nucleus-nucleus experiments performed at the Berkeley Bevalac is presented. Earlier results on projectile and target fragmentation and pion production are briefly summarized. More recent results on Coulomb effects in projectile fragmentation, heavy ion total cross-sections, γ-ray production, and charged particle multiplicities are presented. Also, recent experiments which may shed light on phenomena arising from the central collision of two energetic nuclei, including recent evidence for and against the observation of nuclear shock waves, are reviewed

  20. Scattering of massless vector, tensor, and other particles in string theory at high energy

    International Nuclear Information System (INIS)

    Antonov, E.N.

    1990-01-01

    The 2 → 2 and 2 → 3 processes are studied in the multi-Regge kinematics for gluons and gravitons, the first excited states of the open and closed strings. The factorization of the corresponding amplitudes is demonstrated. Explicit relations generalizing the Low-Gribov expressions are obtained in the kinematics where one of the external particles is produced with small transverse momentum. The expressions in the limit α' → 0 coincide with the results of Yang-Mills theory and gravitation at high energies

  1. Measurement assurance studies of high-energy electron and photon dosimetry in radiation-therapy applications

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlich, M; Soares, C G [National Bureau of Standards, Washington, DC (USA)

    1981-08-01

    This is a brief review of surveys on the dosimetry of radiation-therapy beams by the National Bureau of Standards (NBS). Covered are the NBS ferrous-sulfate (Fricke) dosimetry service, a recently completed survey carried out with thermoluminescence dosimeters (TLD) on the dosimetry in cobalt-60 teletherapy beams, and plans for a TLD survey of dosimetry in high-energy bremsstrahlung beams.

  2. International workshop on the 'Physics of interfaces by synchrotron radiation and other high energy probes'

    International Nuclear Information System (INIS)

    Krummacher, S.; Gudat, W.

    1986-05-01

    The present 'book of abstracts' consists of the abstracts of 23 lectures, held at the international workshop on the 'Physics of interfaces by synchrotron radiation and other high energy probes', April 1986, Bad Honnef, FRG. The subjects are: The use of photoemission in the study of interfaces and adsorbates, EEL spectroscopy applications, spin polarization, photoionization processes and EXAFS. (BHO)

  3. Activities of the Radiation Shielding Information Center and a report on codes/data for high energy radiation transport

    International Nuclear Information System (INIS)

    Roussin, R.W.

    1993-01-01

    From the very early days in its history Radiation Shielding Information Center (RSIC) has been involved with high energy radiation transport. The National Aeronautics and Space Administration was an early sponsor of RSIC until the completion of the Apollo Moon Exploration Program. In addition, the intranuclear cascade work of Bertini at Oak Ridge National Laboratory provided valuable resources which were made available through RSIC. Over the years, RSIC has had interactions with many of the developers of high energy radiation transport computing technology and data libraries and has been able to collect and disseminate this technology. The current status of this technology will be reviewed and prospects for new advancements will be examined

  4. Why is solar cycle 24 an inefficient producer of high-energy particle events?

    Science.gov (United States)

    Vainio, Rami; Raukunen, Osku; Tylka, Allan J.; Dietrich, William F.; Afanasiev, Alexandr

    2017-08-01

    Aims: The aim of the study is to investigate the reason for the low productivity of high-energy SEPs in the present solar cycle. Methods: We employ scaling laws derived from diffusive shock acceleration theory and simulation studies including proton-generated upstream Alfvén waves to find out how the changes observed in the long-term average properties of the erupting and ambient coronal and/or solar wind plasma would affect the ability of shocks to accelerate particles to the highest energies. Results: Provided that self-generated turbulence dominates particle transport around coronal shocks, it is found that the most crucial factors controlling the diffusive shock acceleration process are the number density of seed particles and the plasma density of the ambient medium. Assuming that suprathermal populations provide a fraction of the particles injected to shock acceleration in the corona, we show that the lack of most energetic particle events as well as the lack of low charge-to-mass ratio ion species in the present cycle can be understood as a result of the reduction of average coronal plasma and suprathermal densities in the present cycle over the previous one.

  5. Annotated references on shielding experiment and calculation of high energy particles

    International Nuclear Information System (INIS)

    Hirayama, H.; Ban, S.; Nakamura, T.

    1990-12-01

    The literature on shielding experiment and calculation of high energy particles above 20 MeV has been surveyed. The survey covers thirteen journals, from 1965 up to 1989. For each paper, applicable information is listed on type and energy of the projectile, the accelerator used, composition and thickness of the target and shielding materials, shielding geometry, the experimental and calculational methods, and the quantities obtained. The references on shielding experiment and on shielding calculation are accessed through two indices which list the projectile-target and shielding material combination, shielding geometry and the projectile energy range. The literature on neutron, photon and hadron production from thick target bombarded by charged particles has been surveyed mainly from 1984 as a complement of the previous work. (author)

  6. Theoretical aspects of some collective instabilities in high-energy particle storage rings

    International Nuclear Information System (INIS)

    Ruggiero, F.

    1986-01-01

    After an introduction to single-particle dynamics, based on a unified Hamiltonian treatment of betatron and synchrotron oscillations, we consider two examples of collective instabilities which can limit the performances of high-energy storage rings: the transverse mode coupling instability, due to wake fields, and the incoherent beam-beam instability. Special emphasis is placed on the localization of the interactions between particles and surrounding structures, such as the accelerating RF cavities. We derive an exact invariant for the linearized synchrotron motion and, starting from the Vlasov equation, we discuss the coherent synchro-betatron resonances caused by localized impedance. Under suitable assumptions, we show that the effect of the beam-beam kicks in electron-positron machines can be described by new diffusive terms in a ''renormalized'' Fokker-Planck equation and is therefore equivalent to an additional source of noise for the betatron oscillations. (orig.)

  7. Detectors for particle radiation. 2. rev. ed.

    International Nuclear Information System (INIS)

    Kleinknecht, K.

    1987-01-01

    This book is a description of the set-up and mode of action of detectors for charged particles and gamma radiation for students of physics, as well as for experimental physicists and engineers in research and industry: Ionization chamber, proportional counter, semiconductor counter; proportional chamber, drift chamber, bubble chamber, spark chamber, photomultiplier, laser ionization, silicion strip detector; Cherenkov counter, transition radiation detector; electron-photon-cascade counter, hadron calorimeter; magnetic spectrometer; applications in nuclear medicine, geophysics, space travel, atom physics, nuclear physics, and high-energy physics. With 149 figs., 20 tabs [de

  8. Study of genetic effects of high energy radiations with different ionizing capacities on extracellular phages.

    Science.gov (United States)

    Bresler, S E; Kalinin, V L; Kopylova, Y U; Krivisky, A S; Rybchin, V N; Shelegedin, V N

    1975-07-01

    The inactivating and mutagenic action of high-energy radiations with different ionizing capacities (gamma-rays, protons, alpha-particles and accelerated ions of 12C and 20Ne) was studied by using coliphages lambda11 and SD as subjects. In particular the role of irradiation conditions (broth suspension, pure buffer, dry samples) and of the host functions recA, exrA and polA was investigated. The dose-response curve of induced mutagenesis was studied by measuring the yield of vir mutants in lambda11 and plaque mutants in SD. The following results were obtained. (1) The inactivation kinetics of phages under the action of gamma-rays and protons was first order to a survival of 10(-7). Heavy ions also showed exponential inactivation kinetics to a survival of 10(-4). At higher doses of 20Ne ion bombardment some deviation from one-hit kinetics was observed. For dry samples of phages the dimensions of targets for all types of radiation were approximately proportional to the molecular weights of phage DNA's. For densely ionizing radiation (heavy ions) the inactivating action was 3-5 times weaker than for gamma-rays and protons. (2) Mutagenesis was observed for all types of radiation, but heavy ions were 1-5-2 times less efficient than gamma-rays. For both phages studied the dose-response curve of mutagenesis was non-linear. The dependence on the dose was near to parabolic for lambda11. For SD a plateau or maximum of mutagenesis was observed for the relative number of mutants at a survival of about 10(-4). (3) Host-cell functions recA and exrA were practically indifferent for survival of gamma-irradiated phage lambda11, but indispensable for mutagenesis. Mutation recAI3 abolished induced vir mutations totally and exrA- reduced them significantly. The absence of the function polA had a considerable influence on phage survival, but no effect on vir mutation yield (if compared at the same survival level). (4) In conditions of indirect action of gamma-rays no vir mutations were

  9. Elementary Particle Physics and High Energy Phenomena: Final Report for FY2010-13

    Energy Technology Data Exchange (ETDEWEB)

    Cumalat, John P.; de Alwis, Senarath P.; DeGrand, Thomas A.; DeWolfe, Oliver; Ford, William T.; Hasenfratz, Anna; Mahanthappa, K. T.; Marino, Alysia D.; Nauenberg, Uriel; Smith, James G.; Stenson, Kevin; Wagner, Stephen R.; Zimmerman, Eric D.

    2013-06-27

    The work under this grant consists of experimental, theoretical, and phenomenological research on the fundamental properties of high energy subnuclear particles. The work is conducted at the University of Colorado, the European Organization for Nuclear Research (CERN), the Japan Proton Accelerator Research Complex (J-PARC), Fermi National Accelerator Laboratory (FNAL), SLAC National Accelerator Laboratory (SLAC), Los Alamos National Laboratory (LANL), and other facilities, employing neutrino-beam experiments, test beams of various particles, and proton-proton collider experiments. It emphasizes mass generation and symmetry-breaking, neutrino oscillations, bottom particle production and decay, detector development, supergravity, supersymmetry, superstrings, quantum chromodynamics, nonequilibrium statistical mechanics, cosmology, phase transitions, lattice gauge theory, and anomaly-free theories. The goals are to improve our understanding of the basic building blocks of matter and their interactions. Data from the Large Hadron Collider at CERN have revealed new interactions responsible for particle mass, and perhaps will lead to a more unified picture of the forces among elementary material constituents. To this end our research includes searches for manifestations of theories such as supersymmetry and new gauge bosons, as well as the production and decay of heavy-flavored quarks. Our current work at J-PARC, and future work at new facilities currently under conceptual design, investigate the specifics of how the neutrinos change flavor. The research is integrated with the training of students at all university levels, benefiting both the manpower and intellectual base for future technologies.

  10. N-type doping of InGaN by high energy particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, K.M. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley CA, 94720 (United States)

    2009-06-15

    This article reviews our extensive studies of the effects of native defects introduced by high energy particles on the electrical and optical properties of InGaN alloys. We show that the electronic properties of irradiated InGaN can be well described by the amphoteric defect model. Because of the extremely low position of the conduction band edge of InN the formation energy of native donor defects is very low in In-rich InGaN alloys. High energy particle irradiation of InN and In-rich InGaN, will therefore produce donor defects and result in more n-type materials. As the irradiation dose increases, the electron concentration increases until the Fermi energy E{sub F} approaches the Fermi stabilization energy E{sub FS}. At this point both donor and acceptor-type defects are formed at similar rates, and compensate each other, leading to stabilization of E{sub F} and a saturation of the electron concentration. Hence a large increase and then saturation in the Burstein-Moss shift of the optical absorption edge is also observed. Furthermore we also found that mobilities in the irradiated films can be well described by scattering from triply charged defects, providing strong evidence that native defects in InN are triple donors. The excellent agreement between the experimental results and predictions based on the ADM suggests that particle irradiation can be an effective and simple method to control the doping (electron concentration) in In-rich In{sub x}Ga{sub 1-x}N via native point defects. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  11. N-type doping of InGaN by high energy particle irradiation

    International Nuclear Information System (INIS)

    Yu, K.M.

    2009-01-01

    This article reviews our extensive studies of the effects of native defects introduced by high energy particles on the electrical and optical properties of InGaN alloys. We show that the electronic properties of irradiated InGaN can be well described by the amphoteric defect model. Because of the extremely low position of the conduction band edge of InN the formation energy of native donor defects is very low in In-rich InGaN alloys. High energy particle irradiation of InN and In-rich InGaN, will therefore produce donor defects and result in more n-type materials. As the irradiation dose increases, the electron concentration increases until the Fermi energy E F approaches the Fermi stabilization energy E FS . At this point both donor and acceptor-type defects are formed at similar rates, and compensate each other, leading to stabilization of E F and a saturation of the electron concentration. Hence a large increase and then saturation in the Burstein-Moss shift of the optical absorption edge is also observed. Furthermore we also found that mobilities in the irradiated films can be well described by scattering from triply charged defects, providing strong evidence that native defects in InN are triple donors. The excellent agreement between the experimental results and predictions based on the ADM suggests that particle irradiation can be an effective and simple method to control the doping (electron concentration) in In-rich In x Ga 1-x N via native point defects. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Development of transmission dose estimation algorithm for in vivo dosimetry in high energy radiation treatment

    International Nuclear Information System (INIS)

    Yun, Hyong Geun; Shin, Kyo Chul; Hun, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan; Lee, Hyoung Koo

    2004-01-01

    In vivo dosimetry is very important for quality assurance purpose in high energy radiation treatment. Measurement of transmission dose is a new method of in vivo dosimetry which is noninvasive and easy for daily performance. This study is to develop a tumor dose estimation algorithm using measured transmission dose for open radiation field. For basic beam data, transmission dose was measured with various field size (FS) of square radiation field, phantom thickness (Tp), and phantom chamber distance (PCD) with a acrylic phantom for 6 MV and 10 MV X-ray. Source to chamber distance (SCD) was set to 150 cm. Measurement was conducted with a 0.6 cc Farmer type ion chamber. By using regression analysis of measured basic beam data, a transmission dose estimation algorithm was developed. Accuracy of the algorithm was tested with flat solid phantom with various thickness in various settings of rectangular fields and various PCD. In our developed algorithm, transmission dose was equated to quadratic function of log(A/P) (where A/P is area-perimeter ratio) and the coefficients of the quadratic functions were equated to tertiary functions of PCD. Our developed algorithm could estimate the radiation dose with the errors within ±0.5% for open square field, and with the errors within ±1.0% for open elongated radiation field. Developed algorithm could accurately estimate the transmission dose in open radiation fields with various treatment settings of high energy radiation treatment. (author)

  13. Radiation-hard Silicon Photonics for Future High Energy Physics Experiments

    CERN Document Server

    AUTHOR|(CDS)2089774; Troska, Jan

    Collisions of proton beams in the Large Hadron Collider at CERN produce very high radiation levels in the innermost parts of the particle detectors and enormous amounts of measurement data. Thousands of radiation-hard optical links based on directly-modulated laser diodes are thus installed in the particle detectors to transmit the measurement data to the processing electronics. The radiation levels in the innermost regions of future particle detectors will be much higher than they are now. Alternative solutions to laser-based radiation-hard optical links have to be found since the performance of laser diodes decreases beyond the operation margin of the system when irradiated to sufficiently high radiation levels. Silicon Photonics (SiPh) is currently being investigated as a promising alternative technology. First tests have indeed shown that SiPh Mach-Zehnder modulators (MZMs) are relatively insensitive to a high neutron fluence. However, they showed a strong degradation when exposed to ionizing radiation. ...

  14. Simulation and measurements of the response of an air ionisation chamber exposed to a mixed high-energy radiation field

    International Nuclear Information System (INIS)

    Vincke, H.; Forkel-Wirth, D.; Perrin, D.; Theis, C.

    2005-01-01

    CERN's radiation protection group operates a network of simple and robust ionisation chambers that are installed inside CERN's accelerator tunnels. These ionisation chambers are used for the remote reading of ambient dose rate equivalents inside the machines during beam-off periods. This Radiation Protection Monitor for dose rates due to Induced Radioactivity ('PMI', trade name: PTW, Type 34031) is a non-confined air ionisation plastic chamber which is operated under atmospheric pressure. Besides its current field of operation it is planned to extend the use of this detector in the Large Hadron Collider to measure radiation under beam operation conditions to obtain an indication of the machine performance. Until now, studies of the PMI detector have been limited to the response to photons. In order to evaluate its response to other radiation components, this chamber type was tested at CERF, the high-energy reference field facility at CERN. Six PMI detectors were installed around a copper target being irradiated by a mixed hadron beam with a momentum of 120 GeV c -1 . Each of the chosen detector positions was defined by a different radiation field, varying in type and energy of the incident particles. For all positions, detailed measurements and FLUKA simulations of the detector response were performed. This paper presents the promising comparison between the measurements and simulations and analyses the influence of the different particle types on the resulting detector response. (authors)

  15. A Simple Engineering Analysis of Solar Particle Event High Energy Tails and Their Impact on Vehicle Design

    Science.gov (United States)

    Singleterry, Robert C., Jr.; Walker, Steven A.; Clowdsley, Martha S.

    2016-01-01

    The mathematical models for Solar Particle Event (SPE) high energy tails are constructed with several di erent algorithms. Since limited measured data exist above energies around 400 MeV, this paper arbitrarily de nes the high energy tail as any proton with an energy above 400 MeV. In order to better understand the importance of accurately modeling the high energy tail for SPE spectra, the contribution to astronaut whole body e ective dose equivalent of the high energy portions of three di erent SPE models has been evaluated. To ensure completeness of this analysis, simple and complex geometries were used. This analysis showed that the high energy tail of certain SPEs can be relevant to astronaut exposure and hence safety. Therefore, models of high energy tails for SPEs should be well analyzed and based on data if possible.

  16. High energy particle colliders: past 20 years, next 20 years and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, Vladimir D.; /Fermilab

    2012-04-01

    Particle colliders for high energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the collider has progressed immensely, while the beam energy, luminosity, facility size and the cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but its pace of progress has greatly slowed down. In this paper we very briefly review the method and the history of colliders, discuss in detail the developments over the past two decades and the directions of the R and D toward near future colliders which are currently being explored. Finally, we make an attempt to look beyond the current horizon and outline the changes in the paradigm required for the next breakthroughs.

  17. Changes in the surface electronic states of semiconductor fine particles induced by high energy ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yamaki, Tetsuya; Asai, Keisuke; Ishigure, Kenkichi [Tokyo Univ. (Japan); Shibata, Hiromi

    1997-03-01

    The changes in the surface electronic states of Q-sized semiconductor particles in Langmuir-Blodgett (LB) films, induced by high energy ion irradiation, were examined by observation of ion induced emission and photoluminescence (PL). Various emission bands attributed to different defect sites in the band gap were observed at the initial irradiation stage. As the dose increased, the emissions via the trapping sites decreased in intensity while the band-edge emission developed. This suggests that the ion irradiation would remove almost all the trapping sites in the band gap. The low energy emissions, which show a multiexponential decay, were due to a donor-acceptor recombination between the deeply trapped carriers. It was found that the processes of formation, reaction, and stabilization of the trapping sites would predominantly occur under the photooxidizing conditions. (author)

  18. Characteristics of particle production in high energy nuclear collisions a model-based analysis

    CERN Document Server

    Guptaroy, P; Bhattacharya, S; Bhattacharya, D P

    2002-01-01

    The present work pertains to the production of some very important negatively charged secondaries in lead-lead and gold-gold collisions at AGS, SPS and RHIC energies. We would like to examine here the role of the particular version of sequential chain model (SCM), which was applied widely in the past in analysing data on various high-energy hadronic collisions, in explaining now the latest findings on the features of particle production in the relativistic nucleus-nucleus collisions. The agreement between the model of our choice and the measured data is found to be modestly satisfactory in cases of the most prominent and abundantly produced varieties of the secondaries in the above-stated two nuclear collisions. (25 refs).

  19. Axion-like particle imprint in cosmological very-high-energy sources

    International Nuclear Information System (INIS)

    Domínguez, A.; Sánchez-Conde, M.A.; Prada, F.

    2011-01-01

    Discoveries of very high energy (VHE) photons from distant blazars suggest that, after correction by extragalactic background light (EBL) absorption, there is a flatness or even a turn-up in their spectra at the highest energies that cannot be easily explained by the standard framework. Here, it is shown that a possible solution to this problem is achieved by assuming the existence of axion-like particles (ALPs) with masses ∼ 1 neV. The ALP scenario is tested making use of observations of the highest redshift blazars known in the VHE energy regime, namely 3C 279, 3C 66A, PKS 1222+216 and PG 1553+113. In all cases, better fits to the observed spectra are found when including ALPs rather than considering EBL only. Interestingly, quite similar critical energies for photon/ALP conversions are also derived, independently of the source considered

  20. Measurement assurance studies of high-energy electron and photon dosimetry in radiation-therapy applications

    International Nuclear Information System (INIS)

    Ehrlich, M.; Soares, C.G.

    1981-01-01

    This is a brief review of surveys on the dosimetry of radiation-therapy beams by the National Bureau of Standards (NBS). Covered are the NBS ferrous-sulfate (Fricke) dosimetry service, a recently completed survey carried out with thermoluminescence dosimeters (TLD) on the dosimetry in cobalt-60 teletherapy beams, and plans for a TLD survey of dosimetry in high-energy bremsstrahlung beams. (author)

  1. Diffraction radiation from relativistic particles

    CERN Document Server

    Potylitsyn, Alexander Petrovich; Strikhanov, Mikhail Nikolaevich; Tishchenko, Alexey Alexandrovich

    2010-01-01

    This book deals with diffraction radiation, which implies the boundary problems of electromagnetic radiation theory. Diffraction radiation is generated when a charged particle moves in a vacuum near a target edge. Diffraction radiation of non-relativistic particles is widely used to design intense emitters in the cm wavelength range. Diffraction radiation from relativistic charged particles is important for noninvasive beam diagnostics and design of free electron lasers based on Smith-Purcell radiation which is diffraction radiation from periodic structures. Different analytical models of diffraction radiation and results of recent experimental studies are presented in this book. The book may also serve as guide to classical electrodynamics applications in beam physics and electrodynamics. It can be of great use for young researchers to develop skills and for experienced scientists to obtain new results.

  2. Diffraction radiation from relativistic particles

    International Nuclear Information System (INIS)

    Potylitsyn, Alexander Petrovich; Ryazanov, Mikhail Ivanovich; Strikhanov, Mikhail Nikolaevich; Tishchenko, Alexey Alexandrovich

    2010-01-01

    This book deals with diffraction radiation, which implies the boundary problems of electromagnetic radiation theory. Diffraction radiation is generated when a charged particle moves in a vacuum near a target edge. Diffraction radiation of non-relativistic particles is widely used to design intense emitters in the cm wavelength range. Diffraction radiation from relativistic charged particles is important for noninvasive beam diagnostics and design of free electron lasers based on Smith-Purcell radiation which is diffraction radiation from periodic structures. Different analytical models of diffraction radiation and results of recent experimental studies are presented in this book. The book may also serve as guide to classical electrodynamics applications in beam physics and electrodynamics. It can be of great use for young researchers to develop skills and for experienced scientists to obtain new results. (orig.)

  3. Address on the report of the High Energy Particle Physics Review Group's inquiry into UK participation in high energy particle physics

    International Nuclear Information System (INIS)

    Kendrew, J.

    1985-01-01

    The UK international participation is mainly at CERN although some British high energy physicists work at DESY in Germany, the Fermi Laboratory in the USA and, indeed, elsewhere as well. The UK subscription to CERN is 16% of the budget. The present state of high energy physics at CERN is summarized and the building of LEP explained. The Group's recommendations are that the UK's financial contribution to CERN should continue until LEP is built (by the early 1990s) but should then, because of the prevailing financial climate gradually be reduced by 25%. (U.K.)

  4. Progress in the optoelectronic analog signal transfer for high energy particle detectors

    International Nuclear Information System (INIS)

    Tsang, T.; Radeka, V.

    1992-05-01

    We report the progress in the development of a radiation hard Optoelectronic analog system to transfer particle detector signals with high accuracy. We will present the motivation of this study, the operating principle of the optoelectronic system, the system noise study, the recent R ampersand D efforts on radiation effect, temperature stability, and the realization of an integrated l x l6 optical modulator. The issue of photon source for driving such a large-scale optoelectronic modulators is a major concern. We will address this problem by examining different possible photon sources and comment on other possible alternative for signal transfer

  5. Effect of high-energy radiation on the rheological characteristics and structure of liquid rubbers

    International Nuclear Information System (INIS)

    Govorkov, A.T.; Zaitseva, V.I.; Muryshkin, D.L.; Safonov, Yu.N.

    1987-01-01

    The effect of high-energy radiation (γ-radiation and accelerated electrons) on liquid polybutadiene and polyisoprene rubbers (SKD, SKD-KTR, SKN) and butyl rubber (BR) was studied by IR and EPR spectroscopy, rheoviscosimetry, and chemical analysis. Newtonian flow was conserved in the rubbers under irradiation. The activation energy of viscous flow was unchanged, evidence of an increase in the contour length of the macromolecules without significant branching and cross-linking at the initial stages of the irradiation. A quantitative relationship was established between the rubber's dynamic viscosity and the absorbed dose, and features of the structure-formation mechanism in the liquid rubbers were determined

  6. Comparative effects of exposure to high-energy electrons and gamma radiation on active avoidance behaviour

    International Nuclear Information System (INIS)

    Hunt, W.A.

    1983-01-01

    The effect of two types of ionizing radiation was examined on active avoidance behaviour. Male Sprague-Dawley rats were trained to avoid footshock by jumping onto a retractable ledge. When irradiated with high-energy electrons or gamma photons, their performance was degraded in a dose-dependent manner. However, electrons were 1.6 times as effective as gamma photons with ED50s of 62 and 102 Gy, respectively. All animals recovered within 24 min for all doses used. The data suggest that different types of ionizing radiation may not be equivalent when assessing their effect on behaviour. (author)

  7. The response of film badge dosemeters to high energy photon radiation

    International Nuclear Information System (INIS)

    Playle, T.S.

    1988-12-01

    The sites of the earlier magnox reactor power stations at Berkeley and Bradwell in the United Kingdom are subject to 6 MeV photon radiation from the coolant gas. Since 1966 the Central Electricity Generating Board has included in its film badge personal dosimetry procedures an algorithm for applying a correction for over-response to high energy photon radiation. The correction is based on laboratory irradiations using a source of pure 6 MeV photon radiation. Recently, the opportunity arose to evaluate the response of the film badges at locations around the Berkeley reactors where spectrum-dependent dose equivalent rates had been measured. This report compares the response of the film badge in these characterised radiation environments with the response measured in the calibration laboratory. It is concluded that in the location where measurements were made, the high energy enhancement of measured dose was obscured by the effects of low energy scattered radiation, and it is considered that this will be the case for all practical situations on the power station site. There is therefore no advantage in using the 6 MeV correction factors for routine film badge dosimetry in these locations. (author)

  8. Radiation Build-Up Of High Energy Gamma In Shielding Of High Atomic Number

    International Nuclear Information System (INIS)

    Yuliati, Helfi; Akhadi, Mukhlis

    2000-01-01

    Research to observe effect of radiation build-up factor (b) in iron (Fe) and lead (Pb) for high energy gamma shielding from exp.137 Cs (E gamma : 662 keV) and exp.60 Co (E gamma : 1332 keV) sources has been carried out. Research was conducted bt counting of radiation intensity behind shielding with its thickness vary from 1 to 5 times of half value thickness (HVT). NaI (TI) detector which connected to multi channel analyzer (MCA) was used for the counting. Calculation result show that all of b value are near to 1 (b∼1) both for Fe and Pb. Without inserting b in calculation, from the experiment it was obtained HVT value of Fe for high gamma radiation of 662 and 1332 keV were : (12,94 n 0,03) mm and (17,33 n 0,01) mm with their deviation standards were 0,2% and 0,06% respectively. Value of HVT for Pb with the same energy were : (6,31 n 0,03) mm and (11,86 n 0,03) mm with their deviation standars were : 0,48% and 0,25% respectively. HVL concept could be applied directly to estimate shielding thickness of high atomic number of high energy gamma radiation, without inserting correction of radiation build-up factor

  9. Radiation hardness of Ce-doped sol-gel silica fibers for high energy physics applications.

    Science.gov (United States)

    Cova, Francesca; Moretti, Federico; Fasoli, Mauro; Chiodini, Norberto; Pauwels, Kristof; Auffray, Etiennette; Lucchini, Marco Toliman; Baccaro, Stefania; Cemmi, Alessia; Bártová, Hana; Vedda, Anna

    2018-02-15

    The results of irradiation tests on Ce-doped sol-gel silica using x- and γ-rays up to 10 kGy are reported in order to investigate the radiation hardness of this material for high-energy physics applications. Sol-gel silica fibers with Ce concentrations of 0.0125 and 0.05 mol. % are characterized by means of optical absorption and attenuation length measurements before and after irradiation. The two different techniques give comparable results, evidencing the formation of a main broad radiation-induced absorption band, peaking at about 2.2 eV, related to radiation-induced color centers. The results are compared with those obtained on bulk silica. This study reveals that an improvement of the radiation hardness of Ce-doped silica fibers can be achieved by reducing Ce content inside the fiber core, paving the way for further material development.

  10. High throughput on-chip analysis of high-energy charged particle tracks using lensfree imaging

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Wei; Shabbir, Faizan; Gong, Chao; Gulec, Cagatay; Pigeon, Jeremy; Shaw, Jessica; Greenbaum, Alon; Tochitsky, Sergei; Joshi, Chandrashekhar [Electrical Engineering Department, University of California, Los Angeles, California 90095 (United States); Ozcan, Aydogan, E-mail: ozcan@ucla.edu [Electrical Engineering Department, University of California, Los Angeles, California 90095 (United States); Bioengineering Department, University of California, Los Angeles, California 90095 (United States); California NanoSystems Institute (CNSI), University of California, Los Angeles, California 90095 (United States)

    2015-04-13

    We demonstrate a high-throughput charged particle analysis platform, which is based on lensfree on-chip microscopy for rapid ion track analysis using allyl diglycol carbonate, i.e., CR-39 plastic polymer as the sensing medium. By adopting a wide-area opto-electronic image sensor together with a source-shifting based pixel super-resolution technique, a large CR-39 sample volume (i.e., 4 cm × 4 cm × 0.1 cm) can be imaged in less than 1 min using a compact lensfree on-chip microscope, which detects partially coherent in-line holograms of the ion tracks recorded within the CR-39 detector. After the image capture, using highly parallelized reconstruction and ion track analysis algorithms running on graphics processing units, we reconstruct and analyze the entire volume of a CR-39 detector within ∼1.5 min. This significant reduction in the entire imaging and ion track analysis time not only increases our throughput but also allows us to perform time-resolved analysis of the etching process to monitor and optimize the growth of ion tracks during etching. This computational lensfree imaging platform can provide a much higher throughput and more cost-effective alternative to traditional lens-based scanning optical microscopes for ion track analysis using CR-39 and other passive high energy particle detectors.

  11. High-energy particle emission from galena and pyrite bombarded with Cs and O ions

    International Nuclear Information System (INIS)

    Karpuzov, D.S.; McIntyre, N.S.

    2002-01-01

    The ejection of energetic particles during steady-state ion surface bombardment has been investigated by means of a dynamic computer simulation as well as in a secondary ion mass spectrometry (SIMS)/low-energy ion scattering from surfaces (LEIS) experiment. The emphasis of this comparative study is on the mass dependence of high-energy tails in sputtering and backscattering for the bombardment of galena (PbS) and pyrite (FeS 2 ) with keV energy ion beam of cesium and oxygen. In the experiment, kinetic energy distributions of sputtered secondary ions (S + , Fe + , Pb + , S - ), as well as backscattered or re-sputtered primary ions (Cs + , O + , O - ), have been measured on a modified Cameca IMS-3f magnetic sector mass spectrometer for keV cesium (Cs + ) and oxygen (O 2 + , O - ) bombardment of galena and pyrite. Ejection of high-energy particles, with emission energies of up to ∼40% or up to ∼60% of the bombarding energy for sputtering of the lighter component (S ± ) with cesium or oxygen, respectively, and of up to ∼40% (Cs + ) and ∼80% (O ± ) for backscattering, has been observed for PbS. The computer simulations were based on the well-known MARLOWE code. In order to model the change of the stoichiometry of the binary compounds, dynamic modification of the target composition in the near-surface region was introduced. Cs incorporation was included, and a relative enrichment of the metallic component (Pb, Fe) in the top few layers due to preferential sputtering of sulfur was allowed. The computer simulations provide information on the formation of altered layer under sputter equilibrium as well as on the energy and angular emission distributions of sputtered and backscattered particles in steady-state conditions. Multiple scattering of Cs projectiles and dynamic re-sputtering of cesium that was previously incorporated in the altered near-surface region can be distinguished in the simulation, and matched with the experimental observations. In addition

  12. High energy radiation effects on mechanical properties of butyl rubber compounds

    International Nuclear Information System (INIS)

    Pozenato, Cristina A.; Scagliusi, Sandra R.; Cardoso, Elisabeth C.L.; Lugao, Ademar B.

    2013-01-01

    The high energy radiation on butyl rubber compounds causes a number of chemical reactions that occur after initial ionization and excitation events. These reactions lead to changes in molecular mass of the polymer through scission and crosslinking of the molecules, being able to affect the physical and mechanical properties. Butyl rubber has excellent mechanical properties and oxidation resistance as well as low gas and water vapor permeability. Due to all these properties butyl rubber is widely used industrially and particularly in tires manufacturing. In accordance with various authors, the major effect of high energy, such as gamma rays in butyl rubber, is the yielding of free-radicals along with changes in mechanical properties. There were evaluated effects imparted from high energy radiation on mechanical properties of butyl rubber compounds, non-irradiated and irradiated with 25 kGy, 50 kGy, 150 kGy and 200 kGy. It was also observed a sharp reducing in stress rupture and elongation at break for doses higher than 50 kGy, pointing toward changes in polymeric chain along build-up of free radicals and consequent degradation. (author)

  13. FLARE VERSUS SHOCK ACCELERATION OF HIGH-ENERGY PROTONS IN SOLAR ENERGETIC PARTICLE EVENTS

    International Nuclear Information System (INIS)

    Cliver, E. W.

    2016-01-01

    Recent studies have presented evidence for a significant to dominant role for a flare-resident acceleration process for high-energy protons in large (“gradual”) solar energetic particle (SEP) events, contrary to the more generally held view that such protons are primarily accelerated at shock waves driven by coronal mass ejections (CMEs). The new support for this flare-centric view is provided by correlations between the sizes of X-ray and/or microwave bursts and associated SEP events. For one such study that considered >100 MeV proton events, we present evidence based on CME speeds and widths, shock associations, and electron-to-proton ratios that indicates that events omitted from that investigation’s analysis should have been included. Inclusion of these outlying events reverses the study’s qualitative result and supports shock acceleration of >100 MeV protons. Examination of the ratios of 0.5 MeV electron intensities to >100 MeV proton intensities for the Grechnev et al. event sample provides additional support for shock acceleration of high-energy protons. Simply scaling up a classic “impulsive” SEP event to produce a large >100 MeV proton event implies the existence of prompt 0.5 MeV electron events that are approximately two orders of magnitude larger than are observed. While classic “impulsive” SEP events attributed to flares have high electron-to-proton ratios (≳5 × 10 5 ) due to a near absence of >100 MeV protons, large poorly connected (≥W120) gradual SEP events, attributed to widespread shock acceleration, have electron-to-proton ratios of ∼2 × 10 3 , similar to those of comparably sized well-connected (W20–W90) SEP events.

  14. Finding the bearings of a source of high-energy charged particles

    International Nuclear Information System (INIS)

    Lotyshev, E.V.; Suprunov, V.I.

    1993-01-01

    Different methods are now used to find the direction of a radiation source. One method is based on the analysis information provided by the detection block that includes a system of six two-dimensional coordinate-sensitive semiconductor detectors (CSSDs) forming a cube filled with a special absorber. The CSSD numbers, the coordinates measured by them, and the order of crossing the cube edges bear all the information necessary to find the bearings of a radiation source. However, in this method the efficiency of detection depends on the relative orientation of the detection block and the radiation flux. In addition, the size of the detection block is limited by the condition of direct passage which, in combination with the demand of an unchanging shape, make it impossible to mount it with other devices. In this work the authors address the problem of finding the bearings of a source of charged particles that is fast and allows the detection block to be mounted with the components of other devices. It is shown that the bearings of a source of charged particles can be found by analyzing signals from NN s detector elements located on N s symmetric surfaces inserted into each other and separated by an absorber. The method is fast and makes it possible structurally to combine the detector block with other components. 5 refs., 2 figs

  15. Intercomparison of radiation protection devices in a high-energy stray neutron field. Part III: Instrument response

    International Nuclear Information System (INIS)

    Silari, M.; Agosteo, S.; Beck, P.; Bedogni, R.; Cale, E.; Caresana, M.; Domingo, C.; Donadille, L.; Dubourg, N.; Esposito, A.; Fehrenbacher, G.; Fernandez, F.; Ferrarini, M.; Fiechtner, A.; Fuchs, A.; Garcia, M.J.; Golnik, N.; Gutermuth, F.; Khurana, S.; Klages, Th.

    2009-01-01

    The European Commission has funded within its 6th Framework Programme a three-year project (2005-2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organizational framework for this project was provided by the European radiation Dosimetry Group EURADOS. Work Package 6 of CONRAD dealt with 'complex mixed radiation fields at workplaces' and in this context it organised a benchmark exercise, which included both measurements and calculations, in a stray radiation field at a high-energy particle accelerator at GSI, Germany. The aim was to intercompare the response of several types of active detectors and passive dosemeters in a well-characterised workplace field. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers are discussed in Rollet et al. (2008) and in Wiegel et al. (2008). This paper focuses on the intercomparison of the response of the dosemeters in terms of ambient dose equivalent. The paper describes in detail the detectors employed in the experiment, followed by a discussion of the results. A comparison is also made with the H*(10) values predicted by the Monte Carlo simulations and those measured by the BSS systems.

  16. Preparation and characterization of intrinsically coloured polymers using high energy radiation induced processes

    International Nuclear Information System (INIS)

    Guthrie, J.T.

    1978-07-01

    Information on the development in research is given in the utilization of high energy radiation sources in polymerizations and on polymer characterization in the following three areas: studies on the nitrile-styrene system, studies on the radiation induced polymerization of 2-vinyl anthraquinone and the graft polymerization of vinyl monomers onto cellulose in the DMSO/HCHO/cellulose system. Within the framework of research in radiation induced polymerization, samples of 2-vinyl anthraquinone were subjected to X-ray diffraction and e.s.r. examinations and the kinetics and mechanism of γ-ray induced solution polymerization of 2-vinyl anthraquinone in methylene chloride and dimethyl sulfoxide was investigated. Methylene chloride was found to be an efficient solvent for poly(2-vinyl anthraquinone). The rate of polymerization in methylene chloride was 10 3 times greater than that obtained using dimethyl sulfoxide as solvent

  17. Internet end-to-end performance monitoring for the High Energy Nuclear and Particle Physics community

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, W.

    2000-02-22

    Modern High Energy Nuclear and Particle Physics (HENP) experiments at Laboratories around the world present a significant challenge to wide area networks. Petabytes (1015) or exabytes (1018) of data will be generated during the lifetime of the experiment. Much of this data will be distributed via the Internet to the experiment's collaborators at Universities and Institutes throughout the world for analysis. In order to assess the feasibility of the computing goals of these and future experiments, the HENP networking community is actively monitoring performance across a large part of the Internet used by its collaborators. Since 1995, the pingER project has been collecting data on ping packet loss and round trip times. In January 2000, there are 28 monitoring sites in 15 countries gathering data on over 2,000 end-to-end pairs. HENP labs such as SLAC, Fermi Lab and CERN are using Advanced Network's Surveyor project and monitoring performance from one-way delay of UDP packets. More recently several HENP sites have become involved with NLANR's active measurement program (AMP). In addition SLAC and CERN are part of the RIPE test-traffic project and SLAC is home for a NIMI machine. The large End-to-end performance monitoring infrastructure allows the HENP networking community to chart long term trends and closely examine short term glitches across a wide range of networks and connections. The different methodologies provide opportunities to compare results based on different protocols and statistical samples. Understanding agreement and discrepancies between results provides particular insight into the nature of the network. This paper will highlight the practical side of monitoring by reviewing the special needs of High Energy Nuclear and Particle Physics experiments and provide an overview of the experience of measuring performance across a large number of interconnected networks throughout the world with various methodologies. In particular, results

  18. Internet end-to-end performance monitoring for the High Energy Nuclear and Particle Physics community

    International Nuclear Information System (INIS)

    Matthews, W.

    2000-01-01

    Modern High Energy Nuclear and Particle Physics (HENP) experiments at Laboratories around the world present a significant challenge to wide area networks. Petabytes (1015) or exabytes (1018) of data will be generated during the lifetime of the experiment. Much of this data will be distributed via the Internet to the experiment's collaborators at Universities and Institutes throughout the world for analysis. In order to assess the feasibility of the computing goals of these and future experiments, the HENP networking community is actively monitoring performance across a large part of the Internet used by its collaborators. Since 1995, the pingER project has been collecting data on ping packet loss and round trip times. In January 2000, there are 28 monitoring sites in 15 countries gathering data on over 2,000 end-to-end pairs. HENP labs such as SLAC, Fermi Lab and CERN are using Advanced Network's Surveyor project and monitoring performance from one-way delay of UDP packets. More recently several HENP sites have become involved with NLANR's active measurement program (AMP). In addition SLAC and CERN are part of the RIPE test-traffic project and SLAC is home for a NIMI machine. The large End-to-end performance monitoring infrastructure allows the HENP networking community to chart long term trends and closely examine short term glitches across a wide range of networks and connections. The different methodologies provide opportunities to compare results based on different protocols and statistical samples. Understanding agreement and discrepancies between results provides particular insight into the nature of the network. This paper will highlight the practical side of monitoring by reviewing the special needs of High Energy Nuclear and Particle Physics experiments and provide an overview of the experience of measuring performance across a large number of interconnected networks throughout the world with various methodologies. In particular, results from each project

  19. Reduction of 3-methoxytyramine concentrations in the caudate nucleus of rats after exposure to high-energy iron particles: evidence for deficits in dopaminergic neurons

    International Nuclear Information System (INIS)

    Hunt, W.A.; Dalton, T.K.; Joseph, J.A.; Rabin, B.M.

    1990-01-01

    Exposure to low doses of high-energy iron particles can alter motor behavior. The ability of rats to hang from a wire has been reported to be significantly degraded after exposure to doses as low as 0.5 Gy. In addition, deficits in the ability of acetylcholine to regulate dopamine release in the caudate nucleus (an area in the brain important for motor function) have been found. The concentrations of 3-methoxytyramine (3-MT), a metabolite of dopamine whose concentrations reflect dopamine release in vivo, were measured after rats were exposed to different doses of high-energy iron particles to gain further information about the effect of radiation on the dopaminergic system. Concentrations of 3-MT were significantly reduced 3 days after exposure to 5 Gy but returned to control values by 8 days. After 6 months, concentrations were again less than control values. Exposure to 5 Gy of high-energy electrons or gamma photons had no effect 3 days after exposure. Very high doses of electrons were needed to alter 3-MT concentrations. One hundred grays of electrons decreased 3-MT 30 min after irradiation but levels returned to control values by 60 min. Gamma photons had no effect after doses up to 200 Gy. These results provide further evidence that exposure to heavy particles can degrade motor behavior through an action on dopaminergic mechanisms and that this can occur after doses much lower than those needed for low-LET radiation

  20. Biological effects of particle radiation

    International Nuclear Information System (INIS)

    Sakamoto, Kiyohiko

    1988-01-01

    Conventional radiations such as photons, gamma rays or electrons show several physical or biological disadvantages to bring tumors to cure, therefore, more and more attentions is being paid to new modalitie such as fast neutrons, protons, negative pions and heavy ions, which are expected to overcome some of the defects of the conventional radiations. Except for fast neutrons, these particle radiations show excellet physical dose localization in tissue, moreover, in terms of biological effects, they demonstrate several features compared to conventional radiations, namely low oxygen enhancement ratio, high value of relative biological effectiveness, smaller cellular recovery, larger therapeutic gain factor and less cell cycle dependency in radiation sensitivity. In present paper the biological effects of particle radiations are shown comparing to the effects of conventional radiations. (author)

  1. Highly biocompatible, nanocrystalline hydroxyapatite synthesized in a solvothermal process driven by high energy density microwave radiation

    Science.gov (United States)

    Smolen, Dariusz; Chudoba, Tadeusz; Malka, Iwona; Kedzierska, Aleksandra; Lojkowski, Witold; Swieszkowski, Wojciech; Kurzydlowski, Krzysztof Jan; Kolodziejczyk-Mierzynska, Małgorzata; Lewandowska-Szumiel, Małgorzata

    2013-01-01

    A microwave, solvothermal synthesis of highly biocompatible hydroxyapatite (HAp) nanopowder was developed. The process was conducted in a microwave radiation field having a high energy density of 5 W/mL and over a time less than 2 minutes. The sample measurements included: powder X-ray diffraction, density, specific surface area, and chemical composition. The morphology and structure were investigated by scanning electron microscopy as well as transmission electron microscopy (TEM). The thermal behavior analysis was conducted using a simultaneous thermal analysis technique coupled with quadruple mass spectrometry. Additionally, Fourier transform infrared spectroscopy tests of heated samples were performed. A degradation test and a biocompatibility study in vitro using human osteoblast cells were also conducted. The developed method enables the synthesis of pure, fully crystalline hexagonal HAp nanopowder with a specific surface area close to 240 m2/g and a Ca/P molar ratio equal to 1.57. TEM measurements showed that this method results in particles with an average grain size below 6 nm. A 28-day degradation test conducted according to the ISO standard indicated a 22% loss of initial weight and a calcium ion concentration at 200 μmol/dm3 in the tris(hydroxymethyl)aminomethane hydrochloride test solution. The cytocompatibility of the obtained material was confirmed in a culture of human bone derived cells, both in an indirect test using the material extract, and in direct contact. A quantitative analysis was based on the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide. Viability assay as well as on DNA content measurements in the PicoGreen test. Indirect observations were performed at one point in time according to the ISO standard for in vitro cytotoxicity (ie, after 24 hours of cell exposure to the extracts). The direct contact tests were completed at three time points: after 24 hours, on day 7, and on day 14 of a culture in an osteogenic

  2. Radiation processing of polymers with high energy electron beams: novel materials and processes

    International Nuclear Information System (INIS)

    Sarma, K.S.S.; Sabharwal, Sunil

    2002-01-01

    High-energy ionizing radiation available from electron beam (EB) accelerators has the ability to create extremely reactive species like free radicals or ions at room temperature or even at low temperature in any phase and in a variety of substrates without addition of external additives. This unique advantage of high energy has been utilized in the recent years to produce better quality materials in an environment friendly and cost-effective manner. The availability of high power and reliable EB accelerators has provided new tools to modify the materials and/or processes for a variety of applications. At BARC, a 2 MeV, 20 kW electron beam accelerator has been the nucleus of developing industrial applications of radiation processing in India for last 10 years. The focus has been on developing technologies that are of relevance to Indian socio-economic conditions and also provide economic benefits to the industry. In the areas of polymer processing industry, commercial success has already been achieved while for exploring its applications in the areas of food and agriculture and environment, technology demonstration plants are being set up. The current status of the programme, the new developments and future direction of radiation processing technology shall be presented in this paper. (author)

  3. Radiation hygienization of cattle and swine slurry with high energy electron beam

    International Nuclear Information System (INIS)

    Skowron, Krzysztof; Olszewska, Halina; Paluszak, Zbigniew; Zimek, Zbigniew; Kałuska, Iwona; Skowron, Karolina Jadwiga

    2013-01-01

    The research was carried out to assess the efficiency of radiation hygienization of cattle and swine slurry of different density using the high energy electron beam based on the inactivation rate of Salmonella ssp, Escherichia coli, Enterococcus spp and Ascaris suum eggs. The experiment was conducted with use of the linear electron accelerator Elektronika 10/10 in Institute of Nuclear Chemistry and Technology in Warsaw. The inoculated slurry samples underwent hygienization with high energy electron beam of 1, 3, 5, 7 and 10 kGy. Numbers of reisolated bacteria were determined according to the MPN method, using typical microbiological media. Theoretical lethal doses, D 90 doses and hygienization efficiency of high energy electron beam were determined. The theoretical lethal doses for all tested bacteria ranged from 3.63 to 8.84 kGy and for A. suum eggs from 4.07 to 5.83 kGy. Salmonella rods turned out to be the most sensitive and Enterococcus spp were the most resistant to electron beam hygienization. The effectiveness or radiation hygienization was lower in cattle than in swine slurry and in thick than in thin one. Also the species or even the serotype of bacteria determined the dose needed to inactivation of microorganisms. - Highlights: ► The hygienic efficiency of electron beam against slurry was researched. ► The hygienization efficiency depended on the slurry characteristics and microorganism species. ► In most of the cases 7 kGy dose was sufficient for slurry hygienization. ► Dose below 1 kGy allowed for 90% elimination of microorganism population. ► The radiation hygienization is a good alternative for typical slurry treatment methods

  4. Prototypes of Self-Powered Radiation Detectors Employing Intrinsic High-Energy Current (HEC) (POSTPRINT)

    Science.gov (United States)

    2016-01-01

    neutron sensi- tivities of a Pt self - powered detector ,” IEEE Trans. Nucl. Sci. 25, 292–295 (1978). 6T. A. Dellin, R. E. Huddleston, and C. J...Gamma-sensitive self - powered detectors and their use for in-core flux -mapping,” IEEE Trans. Nucl. Sci. 28, 752–757 (1981). 9E. A. Burke and J. Wall...AFCEC-CX-TY-TP-2016-0006 PROTOTYPES OF SELF - POWERED RADIATION DETECTORS EMPLOYING INTRINSIC HIGH-ENERGY CURRENT (HEC) (POSTPRINT) Piotr

  5. Search for emission of ultra high energy radiation from active galactic nuclei

    International Nuclear Information System (INIS)

    1993-01-01

    A search for emission of ultra-high energy gamma radiation from 13 active galactic nuclei that were detected by EGRET, using the CYGNUS extensive air-shower array, is described. The data set has been searched for continuous emission, emission on the time scale of one week, and for on the time scale of out day. No evidence for emission from any of the AGN on any of the time scales examined was found. The 90% C.L. upper limit to the continuous flux from Mrk 421 above 50 TeV is 7.5 x 10 -14 cm -2 s -1

  6. DCHAIN-SP 2001: High energy particle induced radioactivity calculation code

    Energy Technology Data Exchange (ETDEWEB)

    Kai, Tetsuya; Maekawa, Fujio; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kosako, Kazuaki [Sumitomo Atomic Energy Industries, Ltd., Tokyo (Japan)

    2001-03-01

    For the purpose of contribution to safety design calculations for induced radioactivities in the JAERI/KEK high-intensity proton accelerator project facilities, the DCHAIN-SP which calculates the high energy particle induced radioactivity has been updated to DCHAIN-SP 2001. The following three items were improved: (1) Fission yield data are included to apply the code to experimental facility design for nuclear transmutation of long-lived radioactive waste where fissionable materials are treated. (2) Activation cross section data below 20 MeV are revised. In particular, attentions are paid to cross section data of materials which have close relation to the facilities, i.e., mercury, lead and bismuth, and to tritium production cross sections which are important in terms of safety of the facilities. (3) User-interface for input/output data is sophisticated to perform calculations more efficiently than that in the previous version. Information needed for use of the code is attached in Appendices; the DCHAIN-SP 2001 manual, the procedures of installation and execution of DCHAIN-SP, and sample problems. (author)

  7. Measurement of NdFeB permanent magnets demagnetization induced by high energy electron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Temnykh, Alexander B. [Wilson Lab, Cornell University, LEPP, Ithaca, NY 14850 (United States)], E-mail: abt6@cornell.edu

    2008-03-11

    Demagnetization of NdFeB permanent magnets has been measured as function of radiation dose induced by high energy electrons. The magnet samples were of different intrinsic coercive forces, {approx_equal}12 and {approx_equal}20KOe, dimensions and direction of magnetization. 5 GeV electron beam from 12 GeV Cornell Synchrotron was used as a radiation source. A calorimetric technique was employed for radiation dose measurement. Results indicated that depending on the sample intrinsic coercive force, shape and direction of magnetization the radiation dose causing 1% of demagnetization of the sample varies from 0.0765{+-}0.005Mrad to 11.3{+-}3.0Mrad, i.e., by more than a factor of 100. Experimental data analysis revealed that demagnetization of the given sample induced by radiation is strongly correlated with the sample demagnetizing temperature. This correlation was approximated by an exponential function with two parameters obtained from the data fitting. The function can be used to predict the critical radiation dose for permanent magnet assemblies like undulator magnets based on its demagnetizing temperature. The latter (demagnetization temperature) can be determined at the design stage from 3-D magnetic modeling and permanent magnet material properties.

  8. The high energy multicharged particle exposure of the microbial ecology evaluation device on board the Apollo 16 spacecraft

    Science.gov (United States)

    Benton, E. V.; Henke, R. P.

    1973-01-01

    The high energy multicharged cosmic-ray-particle exposure of the Microbial Ecology Evaluation Device package on board the Apollo 16 spacecraft was monitored using cellulose nitrate, Lexan polycarbonate, nuclear emulsion, and silver chloride crystal nuclear-track detectors. The results of the analysis of these detectors include the measured particle fluences, the linear energy transfer spectra, and the integral atomic number spectrum of stopping particle density. The linear energy transfer spectrum is used to compute the fractional cell loss in human kidney (T1) cells caused by heavy particles. Because the Microbial Ecology Evaluation Device was better shielded, the high-energy multicharged particle exposure was less than that measured on the crew passive dosimeters.

  9. High energy dosimetry

    International Nuclear Information System (INIS)

    Ruhm, W.

    2010-01-01

    Full text: Currently, quantification of doses from high-energy radiation fields is a topical issue. This is so because high-energy neutrons play an important role for radiation exposure of air crew members and personnel outside the shielding of ion therapy facilities. In an effort to study air crew exposure from cosmic radiation in detail, two Bonner Sphere Spectrometers (BSSs) have recently been installed to measure secondary neutrons from cosmic radiation, one at the environmental research station 'Schneefernerhaus' at an altitude of 2650 m on the Zugspitze mountain, Germany, the other at the Koldewey station close to the North Pole on Spitsbergen. Based on the measured neutron fluence distributions and on fluence-to-dose conversion coefficients, mean ambient dose equivalent rate values of 75.0 ± 2.9 nSv/h and 8.7 ± 0.6 nSv/h were obtained for October 2008, respectively. Neutrons with energies above about 20 MeV contribute about 50% to dose, at 2650 m. Ambient dose equivalent rates measured by means of a standard rem counter and an extended rem counter at the Schneefernerhaus confirm this result. In order to study the response of state-of-the-art radiation instrumentation in such a high-energy radiation field, a benchmark exercise that included both measurements in and simulation of the stray neutron radiation field at the high-energy particle accelerator at GSI, Germany, were performed. This CONRAD (COordinated Network for RAdiation Dosimetry) project was funded by the European Commission, and the organizational framework was provided by the European Radiation Dosimetry Group, EURADOS. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers suggest the neutron fluence distributions to be very similar to those of secondary neutrons from cosmic radiation. The results of this intercomparison exercise in terms of ambient dose equivalent are also discussed

  10. Dose measurement techniques for high-energy photon and electron radiation

    International Nuclear Information System (INIS)

    Hohlfeld, K.; Roos, M.

    1992-08-01

    By law the Federal Institute of Physics and Technology (PTB) has been assigned the tasks of representing, preserving and passing on dose units. The analogous continuation of these tasks consists in improving, at the user level, dosimetry techniques in radiation therapy for the benefit of patients. The PTB had an essential share in working out the scientific foundations of dosimetry for high-energy radiation, and the corresponding DIN standards were established with the PTB playing a prominent part. The seminar aimed at presenting the measuring techniques fixed in the new DIN standard 6800 part 2 'Dose measurement techniques according to the probe method - ionization dosimetry', to discuss their physical background and practical implications resulting from them. (orig.) [de

  11. Laboratory astrophysics with high energy and high power lasers: from radiative shocks to young star jets

    International Nuclear Information System (INIS)

    Diziere, A.

    2012-01-01

    Laboratory astrophysics are a rapidly developing domain of the High Energy Density Physics. It aims to recreate at smaller scales physical processes that astronomical telescopes have difficulties observing. We shall approach, in this thesis, three major subjects: 1) Jets ejected from young stars, characterized by an important collimation degree and ending with a bow shock; 2) Radiative shocks in which radiation emitted by the shock front itself plays a dominant role in its structure and 3) Accretion shocks in magnetic cataclysmic variables whose important cooling factor allows them to reach stationarity. From the conception to experimental realization, we shall attempt to reproduce in laboratory each of these processes by respecting the scaling laws linking both situations (experimental and astrophysical) established beforehand. The implementation of a large array of visible and X-ray diagnostics will finally allow to completely characterize them and calculate the dimensionless numbers that validate the astrophysical relevance. (author) [fr

  12. DNA in glasses at 77 K: high energy ionizing radiation versus UV electron injection

    International Nuclear Information System (INIS)

    Malone, M.E.; Parker, A.W.

    1994-01-01

    Most in the field of ionizing radiation damage to DNA in frozen aqueous solutions agree that two major types of radical ions are formed, i.e. . G + / . A + and . T - / . C - . The main evidence stems from EPR and strand break studies. Fluid solutions exposed to laser light are known to give G .+ and e solv - with low yields of single strand breaks. We have explored this contrast by photoionizing DNA solutions at 77 K, in the expectation that this would prevent the formation of e solv - and hence that the results might be similar to those for high energy radiation. They are not: the results show only the formation of G .+ (or) A .+ , the fate of the ejected electrons is unclear except for sodium perchlorate glasses when they react to give O .- . (Author)

  13. Application of TSEE characteristics to high energy radiation dosimetry around an electron linear accelerator

    International Nuclear Information System (INIS)

    Yamamoto, T.; Nakasaku, S.; Kawanishi, M.

    1986-01-01

    The response of the exoelectron dosemeter to the absorbed dose has been investigated with the LiF sample irradiated with high energy electrons from a linear accelerator and γ rays from a 60 Co source. The energy absorbed in the thin surface layer, which can be related to the origins of exoelectron emission, is, in general, smaller than the energy liberated there by primary radiation. In this paper the surface dose is calculated by the Monte Carlo Code EGS4. It is pointed out that the air layer in front of the sample also plays an important role by supplying secondary electrons to the surface region of the sample. The emission density of exoelectrons from a LiF single crystal for unit absorbed dose is found to be 5 x 10 4 electrons.cm -2 .Gy -1 , and nearly constant independent of the low LET radiation type. (author)

  14. Design of two digital radiation tolerant integrated circuits for high energy physics experiments data readout

    CERN Document Server

    Bonacini, Sandro

    2003-01-01

    High Energy Physics research (HEP) involves the design of readout electron- ics for its experiments, which generate a high radiation ¯eld in the detectors. The several integrated circuits placed in the future Large Hadron Collider (LHC) experiments' environment have to resist the radiation and carry out their normal operation. In this thesis I will describe in detail what, during my 10-months partic- ipation in the digital section of the Microelectronics group at CERN, I had the possibility to work on: - The design of a radiation-tolerant data readout digital integrated cir- cuit in a 0.25 ¹m CMOS technology, called \\the Kchip", for the CMS preshower front-end system. This will be described in Chapter 3. - The design of a radiation-tolerant SRAM integrated circuit in a 0.13 ¹m CMOS technology, for technology radiation testing purposes and fu- ture applications in the HEP ¯eld. The SRAM will be described in Chapter 4. All the work has carried out under the supervision and with the help of Dr. Kostas Klouki...

  15. Distributed Optical Fiber Radiation and Temperature Sensing at High Energy Accelerators and Experiments

    CERN Document Server

    AUTHOR|(CDS)2090137; Brugger, Markus

    The aim of this Thesis is to investigate the feasibility of a distributed optical fiber radiation sensing system to be used at high energy physics accelerators and experiments where complex mixed-field environments are present. In particular, after having characterized the response of a selection of radiation sensitive optical fibers to ionizing radiation coming from a 60Co source, the results of distributed optical fiber radiation measurements in a mixed-field environment are presented along with the method to actually estimate the dose variation. This study demonstrates that distributed optical fiber dosimetry in the above mentioned mixed-field radiation environment is feasible, allowing to detect dose variations of about 10-15 Gy with a 1 m spatial resolution. The proof of principle has fully succeeded and we can now tackle the challenge of an industrial installation taking into account that some optimizations need to be done both on the control unit of the system as well as on the choice of the sensing f...

  16. On the cosmological propagation of high energy particles in magnetic fields

    International Nuclear Information System (INIS)

    Alves Batista, Rafael

    2015-04-01

    In the present work the connection between high energy particles and cosmic magnetic fields is explored. Particularly, the focus lies on the propagation of ultra-high energy cosmic rays (UHECRs) and very-high energy gamma rays (VHEGRs) over cosmological distances, under the influence of cosmic magnetic fields. The first part of this work concerns the propagation of UHECRs in the magnetized cosmic web, which was studied both analytically and numerically. A parametrization for the suppression of the UHECR flux at energies ∝ 10 18 eV due to diffusion in extragalactic magnetic fields was found, making it possible to set an upper limit on the energy at which this magnetic horizon effect sets in, which is

  17. Radiation environment in the tunnel of a high-energy proton accelerator at energies near 1 TeV

    International Nuclear Information System (INIS)

    McCaslin, J.B.; Sun, R.K.S.; Swanson, W.P.

    1987-12-01

    Neutron energy spectra, fluence distributions and rates in the FNAL Tevatron tunnel are summarized. This work has application to radiation damage to electronics and research equipment at high energy accelerators, as well as to radiological protection. 7 refs., 4 figs

  18. Models for High-Energy Radiation from Blazars G. E. Romero1 ...

    Indian Academy of Sciences (India)

    Abstract. We discuss on the modelling of blazar jets as emitters of multiwavelength radiation with the implementation of a lepto-hadronic treatment. Assuming that injection of non-thermal electrons and protons can take place at the base of the jet, the stationary particle distributions can be found using an inhomogeneous ...

  19. Influence of incoherent scattering on stochastic deflection of high-energy negative particle beams in bent crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kirillin, I.V. [Akhiezer Institute for Theoretical Physics, National Science Center ' ' Kharkov Institute of Physics and Technology' ' , Kharkov (Ukraine); Shul' ga, N.F. [Akhiezer Institute for Theoretical Physics, National Science Center ' ' Kharkov Institute of Physics and Technology' ' , Kharkov (Ukraine); V.N. Karazin Kharkov National University, Kharkov (Ukraine); Bandiera, L. [INFN Sezione di Ferrara, Ferrara (Italy); Guidi, V.; Mazzolari, A. [INFN Sezione di Ferrara, Ferrara (Italy); Universita degli Studi di Ferrara, Dipartimento di Fisica e Scienze della Terra, Ferrara (Italy)

    2017-02-15

    An investigation on stochastic deflection of high-energy negatively charged particles in a bent crystal was carried out. On the basis of analytical calculation and numerical simulation it was shown that there is a maximum angle at which most of the beam is deflected. The existence of a maximum, which is taken in the correspondence of the optimal radius of curvature, is a novelty with respect to the case of positively charged particles, for which the deflection angle can be freely increased by increasing the crystal length. This difference has to be ascribed to the stronger contribution of incoherent scattering affecting the dynamics of negative particles that move closer to atomic nuclei and electrons. We therefore identified the ideal parameters for the exploitation of axial confinement for negatively charged particle beam manipulation in future high-energy accelerators, e.g., ILC or muon colliders. (orig.)

  20. Time-Resolved Tandem Faraday Cup Development for High Energy TNSA Particles

    Science.gov (United States)

    Padalino, S.; Simone, A.; Turner, E.; Ginnane, M. K.; Glisic, M.; Kousar, B.; Smith, A.; Sangster, C.; Regan, S.

    2015-11-01

    MTW and OMEGA EP Lasers at LLE utilize ultra-intense laser light to produce high-energy ion pulses through Target Normal Sheath Acceleration (TNSA). A Time Resolved Tandem Faraday Cup (TRTF) was designed and built to collect and differentiate protons from heavy ions (HI) produced during TNSA. The TRTF includes a replaceable thickness absorber capable of stopping a range of user-selectable HI emitted from TNSA plasma. HI stop within the primary cup, while less massive particles continue through and deposit their remaining charge in the secondary cup, releasing secondary electrons in the process. The time-resolved beam current generated in each cup will be measured on a fast storage scope in multiple channels. A charge-exchange foil at the TRTF entrance modifies the charge state distribution of HI to a known distribution. Using this distribution and the time of flight of the HI, the total HI current can be determined. Initial tests of the TRTF have been made using a proton beam produced by SUNY Geneseo's 1.7 MV Pelletron accelerator. A substantial reduction in secondary electron production, from 70% of the proton beam current at 2MeV down to 0.7%, was achieved by installing a pair of dipole magnet deflectors which successfully returned the electrons to the cups in the TRTF. Ultimately the TRTF will be used to normalize a variety of nuclear physics cross sections and stopping power measurements. Based in part upon work supported by a DOE NNSA Award#DE-NA0001944.

  1. Final Technical Report Radiation Hard Tight Pitch GaInP SPAD Arrays for High Energy Physics

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, Eric

    2018-01-26

    The specialized photodetectors used in high energy physics experiments often need to remain extremely sensitive for years despite radiation induced damage caused by the constant bombardment of high energy particles. To solve this problem, LightSpin Technologies, Inc. in collaboration with Prof. Bradley Cox and the University of Virginia is developing radiation-hard GaInP photodetectors which are projected to be extraordinarily radiation hard, theoretically capable of withstanding a 100,000-fold higher radiation dose than silicon. In this Phase I SBIR project, LightSpin investigated the performance and radiation hardness of fifth generation GaInP SPAD arrays. These fifth generation devices used a new planar processing approach that enables very tight pitch arrays to be produced. High performance devices with SPAD pitches of 11, 15, and 25 μm were successfully demonstrated, which greatly increased the dynamic range and maximum count rate of the devices. High maximum count rates are critical when considering radiation hardness, since radiation damage causes a proportional increase in the dark count rate, causing SPAD arrays with low maximum count rates (large SPAD pitches) to fail. These GaInP SPAD array Photomultiplier Chips™ were irradiated with protons, electrons, and neutrons. Initial irradiation results were disappointing, with the post-irradiation devices exhibiting excessively high dark currents. The degradation was traced to surface leakage currents that were largely eliminated through the use of trenches etched around the exterior of the Photomultiplier Chip™ (not between SPAD elements). A second round of irradiations on Photomultiplier Chips™ with trenches proved substantially more successful, with post-irradiation dark currents remaining relatively low, though dark count rates were observed to increase at the highest doses. Preliminary analysis of the post-irradiation devices is promising … many of the irradiated Photomultiplier Chips™ still

  2. Structural-morphological variations in pseudo-barrier films of anode aluminium oxide under irradiation with high-energy particles

    International Nuclear Information System (INIS)

    Chernykh, M.A.; Belov, V.T.

    1988-01-01

    Comparative study of structural-morphological variations under electron beam effect in pseudo-barrier films of anode aluminium oxide, obtained in seven different solutions and proton or X-rays pre-irradiated to determine structure peculiarities of anode aluminium oxides, is presented. Such study is a matter of interest from the solid-phase transformation theory point of view and for anode aluminium films application under radiation. Stability increase of pseudo-barrier films of anode aluminium oxide to the effect of UEhMV-100 K microscope electron beam at standard modes of operation (75 kV) due to proton or X-rays irradiation is found. Difference in structural-monorphological variations obtained in different solutions of anode aluminium films under high-energy particles irradiation is determined. Strucural-phase microinhomogeneity of amorphous pseudo-barrier films of anode aluminium oxide and its influence on solid-phase transformations character under electron bean of maximal intensity are detected

  3. Particle-in-cell simulations of high energy electron production by intense laser pulses in underdense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Susumu, Kato; Eisuke, Miura; Kazuyoshi, Koyama [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Mitsumori, Tanimoto [Meisei Univ., Dept. of Electrical Engineering, Hino, Tokyo (Japan); Masahiro, Adachi [Hiroshima Univ., Graduate school of Advanced Science of Matter, Higashi-Hiroshima, Hiroshima (Japan)

    2004-07-01

    The propagation of intense laser pulses and the generation of high energy electrons from underdense plasmas are investigated using two dimensional particle-in-cell simulations. When the ratio of the laser power to the critical power of relativistic self-focusing gets the optimal value, the laser pulse propagates in a steady way and electrons have maximum energies. (author)

  4. Particle-in-cell simulations of high energy electron production by intense laser pulses in underdense plasmas

    International Nuclear Information System (INIS)

    Susumu, Kato; Eisuke, Miura; Kazuyoshi, Koyama; Mitsumori, Tanimoto; Masahiro, Adachi

    2004-01-01

    The propagation of intense laser pulses and the generation of high energy electrons from underdense plasmas are investigated using two dimensional particle-in-cell simulations. When the ratio of the laser power to the critical power of relativistic self-focusing gets the optimal value, the laser pulse propagates in a steady way and electrons have maximum energies. (author)

  5. Detection systems for high energy particle producing gaseous ionization; Sistemas de deteccion de particulas de alta energia mediante ionizacion gaseosa

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, L; Duran, I

    1985-07-01

    This report contains a review on the most used detectors based on the collection of the ionization produced by high energy particles: proportional counters, multiwire proportional chambers, Geiger-Muller counters and drift chambers. In six sections, the fundamental principles, the field configuration and useful gas mixtures, are discussed, most relevant devices are reported along 90 pages with 98 references. (Author) 98 refs.

  6. Particle production in high energy collisions and the non-relativistic quark model

    International Nuclear Information System (INIS)

    Anisovich, V.V.; Nyiri, J.

    1981-07-01

    The present review deals with multiparticle production processes at high energies using ideas which originate in the non-relativistic quark model. Consequences of the approach are considered and they are compared with experimental data. (author)

  7. Elementary particle physics and high energy phenomena. Progress report for FY92

    Energy Technology Data Exchange (ETDEWEB)

    Barker, A.R.; Cumalat, J.P.; de Alwis, S.P.; DeGrand, T.A.; Ford, W.T.; Mahanthappa, K.T.; Nauenberg, U.; Rankin, P.; Smith, J.G.

    1992-06-01

    This report discusses the following research in high energy physics: the properties of the z neutral boson with the SLD detector; the research and development program for the SDC muon detector; the fixed-target k-decay experiments; the Rocky Mountain Consortium for HEP; high energy photoproduction of states containing heavy quarks; and electron-positron physics with the CLEO II and Mark II detectors. (LSP).

  8. Highly biocompatible, nanocrystalline hydroxyapatite synthesized in a solvothermal process driven by high energy density microwave radiation

    Directory of Open Access Journals (Sweden)

    Smolen D

    2013-02-01

    Full Text Available Dariusz Smolen1, Tadeusz Chudoba1, Iwona Malka1, Aleksandra Kedzierska1, Witold Lojkowski1, Wojciech Swieszkowski2, Krzysztof Jan Kurzydlowski2, Malgorzata Kolodziejczyk-Mierzynska3, Malgorzata Lewandowska-Szumiel31Polish Academy of Science, Institute of High Pressure Physics, Warsaw, Poland; 2Faculty of Materials Engineering, Warsaw University of Technology, Warsaw, Poland; 3Department of Histology and Embryology, Center of Biostructure Research, Medical University of Warsaw, Warsaw, PolandAbstract: A microwave, solvothermal synthesis of highly biocompatible hydroxyapatite (HAp nanopowder was developed. The process was conducted in a microwave radiation field having a high energy density of 5 W/mL and over a time less than 2 minutes. The sample measurements included: powder X-ray diffraction, density, specific surface area, and chemical composition. The morphology and structure were investigated by scanning electron microscopy as well as transmission electron microscopy (TEM. The thermal behavior analysis was conducted using a simultaneous thermal analysis technique coupled with quadruple mass spectrometry. Additionally, Fourier transform infrared spectroscopy tests of heated samples were performed. A degradation test and a biocompatibility study in vitro using human osteoblast cells were also conducted. The developed method enables the synthesis of pure, fully crystalline hexagonal HAp nanopowder with a specific surface area close to 240 m2/g and a Ca/P molar ratio equal to 1.57. TEM measurements showed that this method results in particles with an average grain size below 6 nm. A 28-day degradation test conducted according to the ISO standard indicated a 22% loss of initial weight and a calcium ion concentration at 200 µmol/dm3 in the tris(hydroxymethylaminomethane hydrochloride test solution. The cytocompatibility of the obtained material was confirmed in a culture of human bone derived cells, both in an indirect test using the material

  9. Shielding Design and Leaking Measurement for the High Energy Radiation Room

    International Nuclear Information System (INIS)

    Chu, Sung Sil

    1979-01-01

    An optimum shielding design and the computation of protective barriers for high energy radiation therapy room, Toshiba 13 MeV , are presented. We obtained following results by comparison between the p recalculating values and actual survey after complete installation of radio generating units. 1. The precalculating values of protective barrier are 5 times more protective than that of actual measurement. 2. The dose rate during exposure are 2-10 mR /hr at out of the door and the control room. 3. The exposure doses for occupationally persons are relatively low levels, the average values of exposure dose is 10-50 mR per month. 4. The foul smelling and ozone gas production from long exposure of cancer patients cannot be eliminated when the room is ill ventilated

  10. New approach to high energy SU/sub 2L/ /times/ U1 radiative corrections

    International Nuclear Information System (INIS)

    Ward, B.F.L.

    1988-07-01

    We present a new approach to SU/sub 2L/ /times/ U 1 radiative corrections at high energies. Our approach is based on the infrared summation methods of Yennie, Frautschi and Suura, taken together with the Weinberg-'t Hooft renormalization group equation. Specific processes which have been realized via explicit Monte Carlo algorithms are e + e/sup /minus// → f/bar f/' + n(γ), f = μ, /tau/, d, s, u, c, b or t and e + e/sup /minus// → e + e/sup /minus// + n(γ), where n(γ), denotes multiple photo emission on an event-by-event basis. Exemplary Monte Carlo data are presented. 16 refs., 4 figs

  11. Audit of high energy therapy beams in hospital oncology departments by the National Radiation Laboratory

    International Nuclear Information System (INIS)

    Smyth, V.G.

    1994-02-01

    In 1993 the output of every high energy radiotherapy beam used clinically in New Zealand was measured by National Radiation Laboratory (NRL) staff using independent dosimetry equipment. The purpose of this was to audit the dosimetry that is used by hospital physicists for the basis of patient treatments, and to uncover any errors that may be clinically significant. This report analyses the uncertainties involved in comparing the NRL and hospital measurements, and presents the results of the 1993 audit. The overall uncertainty turns out to be about 1.5%. The results for linear accelerator photon beams are consistent with a purely random variation within this uncertainty. Electron beams show some small errors beyond the expected uncertainty. Gamma beams have the potential to be the most accurately measured, but in practice are less accurately measured than linear accelerator beams. None of the disagreements indicated an error of clinical significance. 8 refs., 3 figs., 2 tabs

  12. Effects of sterilisation by high-energy radiation on biomedical poly-(epsilon-caprolactone)/hydroxyapatite composites.

    Science.gov (United States)

    Di Foggia, Michele; Corda, Ugo; Plescia, Elena; Taddei, Paola; Torreggiani, Armida

    2010-06-01

    The effects of a high energy sterilization treatment on poly-epsilon-caprolactone/carbonated hydroxyapatite composites have been investigated. Poly-epsilon-caprolactone is a biodegradable polymer used as long-term bioresorbable scaffold for bone tissue engineering and carbonated hydroxyapatite is a bioactive material able to promote bone growth. The composites were gamma-irradiated in air or under nitrogen atmosphere with doses ranging from 10 to 50 kGy (i.e. to a value higher than that recommended for sterilization). The effects of the irradiation treatment were evaluated by vibrational spectroscopy (IR and Raman spectroscopies) coupled to thermal analysis (Differential Scanning Calorimetry and Thermogravimetry) and Electron Paramagnetic Resonance spectroscopy. Irradiation with the doses required for sterilization induced acceptable structural changes and damaging effects: only a very slight fragmentation of the polymeric chains and some defects in the inorganic component were observed. Moreover, the radiation sensitivity of the composites proved almost the same under the two different atmospheres.

  13. Radiation protection metrology at a high-energy neutron therapy facility

    International Nuclear Information System (INIS)

    Bonnett, D.E.; Sherwin, A.G.; More, B.R.

    1991-01-01

    A radiation protection survey has been carried out at a high-energy neutron therapy facility using a combination of different detectors and counters. Included in the survey were measurements with a tissue equivalent proportional counter (TEPC), a rem meter, a large volume ionisation chamber (LVI) and a Geiger counter. Dose equivalent rates, normalised to a proton beam current of 25 μA, of between 1 μSv.h -1 and 0.7 Sv.h -1 were recorded depending on the location. In general the results confirm the tendency of the rem meter to over-read in fields consisting mainly of low energy neutrons and illustrate the advantages of the diagnostic and gamma discriminating properties of the TEPC. The LVI-Geiger system was found to be the least favourable combination of dosemeters, substantially under-reading and being unable to estimate the neutron dose rate at levels below about 32 μGy.h -1 . (author)

  14. Universality, maximum radiation, and absorption in high-energy collisions of black holes with spin.

    Science.gov (United States)

    Sperhake, Ulrich; Berti, Emanuele; Cardoso, Vitor; Pretorius, Frans

    2013-07-26

    We explore the impact of black hole spins on the dynamics of high-energy black hole collisions. We report results from numerical simulations with γ factors up to 2.49 and dimensionless spin parameter χ=+0.85, +0.6, 0, -0.6, -0.85. We find that the scattering threshold becomes independent of spin at large center-of-mass energies, confirming previous conjectures that structure does not matter in ultrarelativistic collisions. It has further been argued that in this limit all of the kinetic energy of the system may be radiated by fine tuning the impact parameter to threshold. On the contrary, we find that only about 60% of the kinetic energy is radiated for γ=2.49. By monitoring apparent horizons before and after scattering events we show that the "missing energy" is absorbed by the individual black holes in the encounter, and moreover the individual black-hole spins change significantly. We support this conclusion with perturbative calculations. An extrapolation of our results to the limit γ→∞ suggests that about half of the center-of-mass energy of the system can be emitted in gravitational radiation, while the rest must be converted into rest-mass and spin energy.

  15. Shielding for Critical Organs and Radiation Exposure Dose Distribution in Patients with High Energy Radiotherapy

    International Nuclear Information System (INIS)

    Chu, Sung Sil; Suh, Chang Ok; Kim, Gwi Eon

    2002-01-01

    High energy photon beams from medical linear accelerators produce large scattered radiation by various components of the treatment head, collimator and walls or objects in the treatment room including the patient. These scattered radiation do not provide therapeutic dose and are considered a hazard from the radiation safety perspective. Scattered dose of therapeutic high energy radiation beams are contributed significant unwanted dose to the patient. ICRP take the position that a dose of 500mGy may cause abortion at any stage of pregnancy and that radiation detriment to the fetus includes risk of mental retardation with a possible threshold in the dose response relationship around 100 mGy for the gestational period. The ICRP principle of As Low As Reasonably Achievable (ALARA) was recommended for protection of occupation upon the linear no-threshold dose response hypothesis for cancer induction. We suggest this ALARA principle be applied to the fetus and testicle in therapeutic treatment. Radiation dose outside a photon treatment filed is mostly due to scattered photons . This scattered dose is a function of the distance from the beam edge, treatment geometry, primary photon energy, and depth in the patient. The need for effective shielding of the fetus and testicle is reinforced when young patients are treated with external beam radiation therapy and then shielding designed to reduce the scattered photon dose to normal organs have to considered. Irradiation was performed in phantom using high energy photon beams produced by a Varian 2100C/D medical linear accelerator (Varian Oncology Systems, Polo Alto, CA) located at the Yonsei Cancer Center. The composite phantom used was comprised of a commercially available anthropomorphic Rando phantom (Phantom Laboratory Inc., Salem, YN) and a rectangular solid polystyrene phantom of dimensions 30cm x 30cm x 20cm. The anthropomorphic Rando phantom represents an average man made from tissue equivalent materials that is

  16. Shielding for Critical Organs and Radiation Exposure Dose Distribution in Patients with High Energy Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Sung Sil; Suh, Chang Ok; Kim, Gwi Eon [Yonsei Univ., Seoul (Korea, Republic of)

    2002-03-15

    High energy photon beams from medical linear accelerators produce large scattered radiation by various components of the treatment head, collimator and walls or objects in the treatment room including the patient. These scattered radiation do not provide therapeutic dose and are considered a hazard from the radiation safety perspective. Scattered dose of therapeutic high energy radiation beams are contributed significant unwanted dose to the patient. ICRP take the position that a dose of 500mGy may cause abortion at any stage of pregnancy and that radiation detriment to the fetus includes risk of mental retardation with a possible threshold in the dose response relationship around 100 mGy for the gestational period. The ICRP principle of As Low As Reasonably Achievable (ALARA) was recommended for protection of occupation upon the linear no-threshold dose response hypothesis for cancer induction. We suggest this ALARA principle be applied to the fetus and testicle in therapeutic treatment. Radiation dose outside a photon treatment filed is mostly due to scattered photons . This scattered dose is a function of the distance from the beam edge, treatment geometry, primary photon energy, and depth in the patient. The need for effective shielding of the fetus and testicle is reinforced when young patients are treated with external beam radiation therapy and then shielding designed to reduce the scattered photon dose to normal organs have to considered. Irradiation was performed in phantom using high energy photon beams produced by a Varian 2100C/D medical linear accelerator (Varian Oncology Systems, Polo Alto, CA) located at the Yonsei Cancer Center. The composite phantom used was comprised of a commercially available anthropomorphic Rando phantom (Phantom Laboratory Inc., Salem, YN) and a rectangular solid polystyrene phantom of dimensions 30cm x 30cm x 20cm. The anthropomorphic Rando phantom represents an average man made from tissue equivalent materials that is

  17. Baryon scattering at high energies. Wave function, impact factor, and gluon radiation

    International Nuclear Information System (INIS)

    Bartels, J.; Motyka, L.; Jagellonian Univ., Krakow

    2007-11-01

    The scattering of a baryon consisting of three massive quarks is investigated in the high energy limit of perturbative QCD. A model of a relativistic proton-like wave function, dependent on valence quark longitudinal and transverse momenta and on quark helicities, is proposed, and we derive the baryon impact factors for two, three and four t-channel gluons. We find that the baryonic impact factor can be written as a sum of three pieces: in the first one a subsystem consisting of two of the three quarks behaves very much like the quark-antiquark pair in γ * scattering, whereas the third quark acts as a spectator. The second term belongs to the odderon, whereas in the third (C-even) piece all three quarks participate in the scattering. This term is new and has no analogue in γ * scattering. We also study the small x evolution of gluon radiation for each of these three terms. The first term follows the same pattern of gluon radiation as the γ * -initiated quark-antiquark dipole, and, in particular, it contains the BFKL evolution followed by the 2→4 transition vertex (triple Pomeron vertex). The odderon-term is described by the standard BKP evolution, and the baryon couples to both known odderon solutions, the Janik-Wosiek solution and the BLV solution. Finally, the t-channel evolution of the third term starts with a three reggeized gluon state which then, via a new 3→4 transition vertex, couples to the four gluon (two-Pomeron) state. We briefly discuss a few consequences of these findings, in particular the pattern of unitarization of high energy baryon scattering amplitudes. (orig.)

  18. Baryon scattering at high energies. Wave function, impact factor, and gluon radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bartels, J. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Motyka, L. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik]|[Jagellonian Univ., Krakow (Poland). Inst. of Physics

    2007-11-15

    The scattering of a baryon consisting of three massive quarks is investigated in the high energy limit of perturbative QCD. A model of a relativistic proton-like wave function, dependent on valence quark longitudinal and transverse momenta and on quark helicities, is proposed, and we derive the baryon impact factors for two, three and four t-channel gluons. We find that the baryonic impact factor can be written as a sum of three pieces: in the first one a subsystem consisting of two of the three quarks behaves very much like the quark-antiquark pair in {gamma}{sup *} scattering, whereas the third quark acts as a spectator. The second term belongs to the odderon, whereas in the third (C-even) piece all three quarks participate in the scattering. This term is new and has no analogue in {gamma}{sup *} scattering. We also study the small x evolution of gluon radiation for each of these three terms. The first term follows the same pattern of gluon radiation as the {gamma}{sup *}-initiated quark-antiquark dipole, and, in particular, it contains the BFKL evolution followed by the 2{yields}4 transition vertex (triple Pomeron vertex). The odderon-term is described by the standard BKP evolution, and the baryon couples to both known odderon solutions, the Janik-Wosiek solution and the BLV solution. Finally, the t-channel evolution of the third term starts with a three reggeized gluon state which then, via a new 3{yields}4 transition vertex, couples to the four gluon (two-Pomeron) state. We briefly discuss a few consequences of these findings, in particular the pattern of unitarization of high energy baryon scattering amplitudes. (orig.)

  19. High-energy Emission from Nonrelativistic Radiative Shocks: Application to Gamma-Ray Novae

    Science.gov (United States)

    Vurm, Indrek; Metzger, Brian D.

    2018-01-01

    The observation of GeV gamma-rays from novae by Fermi/LAT demonstrates that the nonrelativistic radiative shocks in these systems can accelerate particles to energies of at least ∼10 GeV. The low-energy extension of the same nonthermal particle distribution inevitably gives rise to emission in the hard X-ray band. Above ≳ 10 {keV}, this radiation can escape the system without significant absorption/attenuation, and can potentially be detected by NuSTAR. We present theoretical models for hard X-ray and gamma-ray emission from radiative shocks in both leptonic and hadronic scenarios, accounting for the rapid evolution of the downstream properties due to the fast cooling of thermal plasma. We find that due to strong Coulomb losses, only a fraction of {10}-4{--}{10}-3 of the gamma-ray luminosity is radiated in the NuSTAR band; nevertheless, this emission could be detectable simultaneously with the LAT emission in bright gamma-ray novae with a ∼50 ks exposure. The spectral slope in hard X-rays is α ≈ 0 for typical nova parameters, thus serving as a testable prediction of the model. Our work demonstrates how combined hard X-ray and gamma-ray observations can be used to constrain properties of the nova outflow (velocity, density, and mass outflow rate) and particle acceleration at the shock. A very low X-ray to gamma-ray luminosity ratio ({L}{{X}}/{L}γ ≲ 5× {10}-4) would disfavor leptonic models for the gamma-ray emission. Our model can also be applied to other astrophysical environments with radiative shocks, including SNe IIn and colliding winds in massive star binaries.

  20. Final Report. Hydrodynamics by high-energy-density plasma flow and hydrodynamics and radiative hydrodynamics with astrophysical application

    International Nuclear Information System (INIS)

    R Paul Drake

    2004-01-01

    OAK-B135 This is the final report from the project Hydrodynamics by High-Energy-Density Plasma Flow and Hydrodynamics and Radiation Hydrodynamics with Astrophysical Applications. This project supported a group at the University of Michigan in the invention, design, performance, and analysis of experiments using high-energy-density research facilities. The experiments explored compressible nonlinear hydrodynamics, in particular at decelerating interfaces, and the radiation hydrodynamics of strong shock waves. It has application to supernovae, astrophysical jets, shock-cloud interactions, and radiative shock waves

  1. Elementary particle physics and high energy phenomena. [Dept. of Physics, Univ. of Colorado, Boulder, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Barker, A.R.; Cumalat, J.P.; De Alwis, S.P.; DeGrand, T.A.; Ford, W.T.; Mahanthappa, K.T.; Nauenberg, U.; Rankin, P.; Smith, J.G.

    1992-06-01

    Experimental and theoretical high-energy physics programs at the University of Colorado are reported. Areas of concentration include the following: study of the properties of the Z[sup 0] with the SLD detector; fixed-target K-decay experiments; the R D program for the muon system: the SDC detector; high-energy photoproduction of states containing heavy quarks; electron--positron physics with the CLEO II detector at CESR; lattice QCD; and spin models and dynamically triangulated random surfaces. 24 figs., 2 tabs., 117 refs.

  2. Elementary particle physics and high energy phenomena. Progress report for FY93

    Energy Technology Data Exchange (ETDEWEB)

    Barker, A.R.; Cumalat, J.P.; De Alwis, S.P.; DeGrand, T.A.; Ford, W.T.; Mahanthappa, K.T.; Nauenberg, U.; Rankin, P.; Smith, J.G.

    1992-06-01

    Experimental and theoretical high-energy physics programs at the University of Colorado are reported. Areas of concentration include the following: study of the properties of the Z{sup 0} with the SLD detector; fixed-target K-decay experiments; the R&D program for the muon system: the SDC detector; high-energy photoproduction of states containing heavy quarks; electron--positron physics with the CLEO II detector at CESR; lattice QCD; and spin models and dynamically triangulated random surfaces. 24 figs., 2 tabs., 117 refs.

  3. Peroxidation of the dried thin film of lipid by high-energy alpha particles from a cyclotron

    International Nuclear Information System (INIS)

    Agarwal, S.; Chatterjee, S.N.

    1984-01-01

    High-energy α particles produced a dose-dependent linear increase in different lipid peroxidation products (e.g., malondialdehyde (MDA), conjugated dienes, and hydroperoxides) in the dried thin film state. An inverse dose-rate effect was observed when the dose rate was varied by changing either the α-particle fluence rate or the α-particle energy. The antioxidants α-tocopherol and butylated hydroxytoluene (BHT) suppressed the α-particle-induced lipid peroxidation in the dried thin film state, and in this respect α-tocopherol was found superior to BHT. It was found that α-tocopherol was equally efficient in inhibiting lipid peroxidations by α particles and ultraviolet light

  4. Studies in theoretical high energy particle physics: Technical progress report [February 1987-February 1988

    International Nuclear Information System (INIS)

    Sukhatme, U.P.; Keung, Wai-Yee; Kovacs, E.

    1988-02-01

    This is a technical progress report for grant No. FG02-84ER40173 for the period February 1987 to February 1988. Our research on supersymmetric quantum mechanics has yielded many interesting results. In particular, a systematic approach to the tunneling problem in double well potentials has been developed. Higgs boson related physics at the high energy hadron colliders has been extensively studied

  5. A new trends in high-energy physics. Current topics in nuclear and particle physics

    International Nuclear Information System (INIS)

    Terazawa, H.

    2001-01-01

    The hottest subjects in high energy physics for the last couple of years are discussed in some details. The contents of this talk include: exotic nuclei; color ball as pomeron; neutrino masses and mixings; Higgs scalar mass; superparticles; substructure of quarks and leptons; structure of the universe and conclusion and future prospects

  6. EFFECTS OF SPIN ON HIGH-ENERGY RADIATION FROM ACCRETING BLACK HOLES

    Energy Technology Data Exchange (ETDEWEB)

    O’ Riordan, Michael; Pe’er, Asaf [Physics Department, University College Cork, Cork (Ireland); McKinney, Jonathan C., E-mail: michael_oriordan@umail.ucc.ie [Department of Physics and Joint Space-Science Institute, University of Maryland, College Park, MD 20742 (United States)

    2016-11-01

    Observations of jets in X-ray binaries show a correlation between radio power and black hole spin. This correlation, if confirmed, points toward the idea that relativistic jets may be powered by the rotational energy of black holes. In order to examine this further, we perform general relativistic radiative transport calculations on magnetically arrested accretion flows, which are known to produce powerful jets via the Blandford–Znajek (BZ) mechanism. We find that the X-ray and γ -ray emission strongly depend on spin and inclination angle. Surprisingly, the high-energy power does not show the same dependence on spin as the BZ jet power, but instead can be understood as a redshift effect. In particular, photons observed perpendicular to the spin axis suffer little net redshift until originating from close to the horizon. Such observers see deeper into the hot, dense, highly magnetized inner disk region. This effect is largest for rapidly rotating black holes due to a combination of frame dragging and decreasing horizon radius. While the X-ray emission is dominated by the near horizon region, the near-infrared (NIR) radiation originates at larger radii. Therefore, the ratio of X-ray to NIR power is an observational signature of black hole spin.

  7. Measurement of leakage and design for the protective barrier of the high energy radiation therapy room

    International Nuclear Information System (INIS)

    Chu, S.S.; Park, C.Y.

    1981-01-01

    The logical development of an optimum structural shielding design and the computation of protective barriers for high energy radiation therapy room, Toshiba 13 MeV are presented. We obtained following results by comparison in between the precalculating values and actual survey after complete installation of radiogenerating units. 1) The calculating formula for the protective barrier written in NCRP report no. 34(1970) was the most ideal and economic calculating methods for the construction of barrier and to determine thickness for the meeting requirements of the number of patients of 80-100 in daily treatment. 2) The precalculating values of protective barrier are 5 times more protective than that of actual measurement. It is depending on radiation workload and utilization the data most securely. 3) The dose rate during exposure are 2-10 mR/hr at out of the door and the control room. 4) The foul smelling and ozone gas production from long exposure of cancer patients cannot be estimated when the room is ill ventilated. (author)

  8. Microsystem for remote sensing of high energy radiation with associated extremely low photon flux densities

    Science.gov (United States)

    Otten, A.; Jain, V. K.

    2015-08-01

    This paper presents a microsystem for remote sensing of high energy radiation in extremely low flux density conditions. With wide deployment in mind, potential applications range from nuclear non-proliferation, to hospital radiation-safety. The daunting challenge is the low level of photon flux densities - emerging from a Scintillation Crystal (SC) on to a ~1 mm-square detector, which are a factor of 10000 or so lower than those acceptable to recently reported photonic chips (including `single-photon detection' chips), due to a combination of low Lux, small detector size, and short duration SC output pulses - on the order of 1 μs. These challenges are attempted to be overcome by the design of an innovative `System on a Chip' type microchip, with high detector sensitivity, and effective coupling from the SC to the photodetector. The microchip houses a tiny n+ diff p-epi photodiode (PD) as well as the associated analog amplification and other related circuitry, all fabricated in 0.5micron, 3-metal 2-poly CMOS technology. The amplification, together with pulse-shaping of the photocurrent-induced voltage signal, is achieved through a tandem of two capacitively coupled, double-cascode amplifiers. Included in the paper are theoretical estimates and experimental results.

  9. A low power high speed radiation hard serializer for High Energy Physics experiments

    CERN Document Server

    AUTHOR|(CDS)2080243; Marchioro, Alessandro; Ottavi, Marco

    This Ph.D. thesis focuses on the development and the characterization of novel solutions for electronic systems for high-speed data transmission in extremely high radio-active environment (e.g. high energy physics application). The text proposes two alternative full-custom solutions for a fundamental enabling block for a lowpower serial data transmission system, the serializer. This block will find place in a future transceiver conceived for the future upgraded phase of the Large Hadron Collider, or LHC, at CERN. The first solution proposed, called “triple module redundancy”, is based on hardware redundancy, a well-known solution, to obtain protection against the temporary malfunctioning induced by radiation. In the second case a new architecture, called “code protected”, is proposed. This architecture takes advantage of the error correction code present in the data word to obtain radiation robustness on data and some parts of the control logic and to further reduce the power consumption. A test chip ...

  10. High energy synchrotron radiation. A new probe for condensed matter research

    International Nuclear Information System (INIS)

    Schneider, J.R.; Bouchard, R.; Brueckel, T.; Lippert, M.; Neumann, H.B.; Poulsen, H.F.; Ruett, U.; Schmidt, T.; Zimmermann, M. von

    1994-01-01

    The absorption of 150 keV synchrotron radiation in matter is weak and, as normally done with neutrons, bulk properties are studied in large samples. However, the k-space resolution obtained with a Triple Crystal Diffractometer (TCD) for high energy synchrotron radiation is about one order of magnitude better than in high resolution neutron diffraction. The technique has been applied to measure the structure factor S(Q) of amorphous solids up to momentum transfers of the order of 32 A -1 , to study the intermediate range Ortho-II ordering in large, high quality YBa 2 Cu 3 O 6.5 single crystals and for investigations of the defect scattering from annealed Czochralski grown silicon crystals. Magnetic superlattice reflections have been measured in MnF 2 demonstrating the potential of the technique for high resolution studies of ground state bulk antiferromagnetism. Recently the question of two length scales in the critical scattering at the 100 K phase transition in SrTiO 3 was studied. At the PETRA storage ring, which serves as an accumulator for the HERA electron-proton-ring at DESY and which can be operated up to electron energies of 12 GeV, an undulator beam line is currently under construction and should be available in summer 1995. It opens up exciting new research opportunities for photon energies from about 20 to 150 keV. (orig.)

  11. High-energy radiation from collisions of high-velocity clouds and the Galactic disc

    Science.gov (United States)

    del Valle, Maria V.; Müller, A. L.; Romero, G. E.

    2018-04-01

    High-velocity clouds (HVCs) are interstellar clouds of atomic hydrogen that do not follow normal Galactic rotation and have velocities of a several hundred kilometres per second. A considerable number of these clouds are falling down towards the Galactic disc. HVCs form large and massive complexes, so if they collide with the disc a great amount of energy would be released into the interstellar medium. The cloud-disc interaction produces two shocks: one propagates through the cloud and the other through the disc. The properties of these shocks depend mainly on the cloud velocity and the disc-cloud density ratio. In this work, we study the conditions necessary for these shocks to accelerate particles by diffusive shock acceleration and we study the non-thermal radiation that is produced. We analyse particle acceleration in both the cloud and disc shocks. Solving a time-dependent two-dimensional transport equation for both relativistic electrons and protons, we obtain particle distributions and non-thermal spectral energy distributions. In a shocked cloud, significant synchrotron radio emission is produced along with soft gamma rays. In the case of acceleration in the shocked disc, the non-thermal radiation is stronger; the gamma rays, of leptonic origin, might be detectable with current instruments. A large number of protons are injected into the Galactic interstellar medium, and locally exceed the cosmic ray background. We conclude that under adequate conditions the contribution from HVC-disc collisions to the galactic population of relativistic particles and the associated extended non-thermal radiation might be important.

  12. Spin-1/2 particles in non-inertial reference frames. Low- and high-energy approximations

    International Nuclear Information System (INIS)

    Singh, D.; Papini, G.

    2000-01-01

    Spin-1/2 particles can be used to study inertial and gravitational effects by means of interferometers, particle accelerators, and ultimately quantum systems. These studies require, in general, knowledge of the Hamiltonian and of the inertial and gravitational quantum phases. The procedure followed gives both in the low- and high-energy approximations. The latter affords a more consistent treatment of mass at high energies. The procedure is based on general relativity and on a solution of the Dirac equation that is exact to first-order in the metric deviation. Several previously known acceleration- and rotation-induced effects are rederived in a comprehensive, unified way. Several new effects involve spin, electromagnetic and inertial/gravitational fields in different combinations

  13. Multi-particle correlation observables in high energy nucleus-nucleus collisions

    International Nuclear Information System (INIS)

    Stock, R.

    1981-01-01

    Global features of exclusively measured events, including number correlations and vector correlations, and hybrid analysis of measurements of one or two specific fragments like spectator nuclei, high transverse momentum particles, polarization of one particle, etc., are considered

  14. Arcing and rf signal generation during target irradiation by a high-energy, pulsed neutral particle beam

    International Nuclear Information System (INIS)

    Robiscoe, R.T.

    1988-02-01

    We present a theory describing the dynamics of arc discharges in bulk dielectric materials on board space-based vehicles. Such ''punch-through'' arcs can occur in target satellites irradiated by high-energy (250 MeV), pulsed (100 mA x 10 ms) neutral particle beams. We treat the arc as a capacitively limited avalanche current in the target dielectric material, and we find expressions for the arc duration, charge transport, currents, and discharge energy. These quantities are adjusted to be consistent with known scaling laws for the area of charge depleted by the arc. After a brief account of the statistical distribution of voltages at which the arc starts and stops, we calculate the signal strength and frequency spectrum of the electromagnetic radiation broadcast by the arc. We find that arcs from thick (/similar to/1 cm) targets can generate rf signals detectable up to 1000 km from the target, bu a radio receiver operating at frequency 80 MHz, bandwidth 100 kHz, and detection threshold -105 dBm. These thick-target arc signals are 10 to 20 dB above ambient noise at the receiver, and they provide target hit assessment if the signal spectrum can be sampled at several frequencies in the nominal range 30-200 MHz. Thin-target (/similar to/1 mm) arc signals are much weaker, but when they are detecable in conjunction with thick-target signals, target discrimination is possible by comparing the signal frequency spectra. 24 refs., 12 figs

  15. Simulation of electron density disturbances of the ionospheric D region produced by high-energy particle fluxes

    International Nuclear Information System (INIS)

    Martynenko, S.I.

    1989-01-01

    Using the large-scale tim expansion analytical solutions of electron concentration balance equation in D-region of the ionosphere for pulsed and periodic changes in the rate of ion formatin under the effect of fluxes of precipitating high-energy particles are obtained. Possible effect of disturbances of temperature of nutrals is taken into account. On the basis of model representations the space-time structure of emerging ionospheric disturbances is discussed

  16. The origin of mass and experiments on high-energy particle accelerators

    International Nuclear Information System (INIS)

    Ioffe, B.L.

    2006-01-01

    The visible world is one consisting of nucleons and electrons. The mass of nucleon arises from chiral symmetry breaking in quantum chromodynamics, so high energy accelerator experiments cannot give a clue to the nature of mass of matter in the visible world. The origin of the mass of the matter will be clarified when the mechanism of chiral symmetry breaking in quantum chromodynamics is established [ru

  17. Research in high energy elementary particle physics: Annual progress report, [March 1, 1986-February 29, 1988

    International Nuclear Information System (INIS)

    Field, R.; Ramond, P.; Thorn, C.; Avery, P.; Walker, J.; Tanner, D.; Sikivie, P.; Sullivan, N.; Majeswki, S.

    1988-01-01

    This is a progress report covering the period March 1, 1986 through February 29, 1988 for the High Energy Physics program at the University of Florida (DOE Florida Demonstration Project grant FG05-86-ER40272). Our research program covers a braod range of topics in theoretical and experimental physics and includes detector development and an Axion search. Included in this report is a summary of our program and a discussion of the research progress

  18. Radiation effects for high-energy protons and X-ray in integrated circuits

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, M.A.G.; Santos, R.B.B. [Centro Universitario da FEI, Sao Bernardo do Campo, SP (Brazil); Medina, N.H.; Added, N.; Tabacniks, M.H. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica; Lima, J.A. de [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil); Cirne, K.H. [Empresa Brasileira de Aeronautica S.A. (EMBRAER), Sao Jose dos Campos, SP (Brazil)

    2012-07-01

    Full text: Electronic circuits are strongly influenced by ionizing radiation. The necessity to develop integrated circuits (IC's) featuring radiation hardness is largely growing to meet the stringent environment in space electronics [1]. This work aims to development a test platform to qualify electronic devices under the influence of high radiation dose, for aerospace applications. To understand the physical phenomena responsible for changes in devices exposed to ionizing radiation several kinds of radiation should then be considered, among them heavy ions, alpha particles, protons, gamma and X-rays. Radiation effects on the ICs are usually divided into three categories: Total Ionizing Dose (TID), a cumulative dose that shifts the threshold voltage and increases transistor's off-state current; Single Events Effects (SEE), a transient effect which can deposit charge directly into the device and disturb the properties of electronic circuits and Displacement Damage (DD) which can change the arrangement of the atoms in the lattice [2]. In this study we are investigating the radiation effects in rectangular-gate and circular-gate MOSFETs, manufactured with standard CMOS fabrication process, using particle beams produced in electrostatic tandem accelerators and X-rays. Initial tests for TID effects were performed using the 1.7 MV 5SDH tandem Pelletron accelerator of the Instituto de Fisica da USP with a proton beam of 2.6 MeV. The devices were exposed to different doses, varying the beam current, and irradiation time with the accumulated dose reaching up to Grad. To study the effect of X-rays on the electronic devices, an XRD-7000 (Shimadzu) X-ray setup was used as a primary X-ray source. The devices were irradiated with a total dose from krad to Grad using different dose rates. The results indicate that changes of the I-V characteristic curve are strongly dependents on the geometry of the devices. [1] Duzellier, S., Aerospace Science and Technology 9, p. 93

  19. Characteristics of Cu–Al2O3 composites of various starting particle size obtained by high-energy milling

    Directory of Open Access Journals (Sweden)

    VIŠESLAVA RAJKOVIĆ

    2009-05-01

    Full Text Available The powder Cu– Al2O3 composites were produced by high-energy milling. Various combinations of particle size and mixtures and approximately constant amount of Al2O3 were used as the starting materials. These powders were separately milled in air for up to 20 h in a planetary ball mill. The copper matrix was reinforced by internal oxidation and mechanical alloying. During the milling, internal oxidation of pre-alloyed Cu-2 mass %-Al powder generated 3.7 mass % Al2O3 nano-sized particles finely dispersed in the copper matrix. The effect of different size of the starting copper and Al2O3 powder particles on the lattice parameter, lattice distortion and grain size, as well as on the size, morphology and microstructure of the Cu– Al2O3 composite powder particles was studied.

  20. Particle identification via transition radiation and detectors

    International Nuclear Information System (INIS)

    Egorytchev, V.; Saveliev, V.; Aplin, S.J.

    2000-01-01

    Transition radiation detectors show great promise for the purposes of lepton identification in existing and future experiments in high-energy physics such as HERA-B, ATLAS, ALICE in high-luminosity environment. More high performance can be expected in low-luminosity conditions - neutrino experiments (NOMAD), and ideal condition for the use of transition radiation detectors in flying and space high-energy experiments (AMS). This paper discusses the practical theory of transition radiation, basic equation and algorithm suitable for detailed analysis of transition radiation and optimization of transition radiation detectors in the area of experimental high-energy physics. The results are based on detailed Monte Carlo simulation of transition radiation introduced in GEANT and experimental results

  1. Particle identification via transition radiation and detectors

    CERN Document Server

    Egorytchev, V; Aplin, S J

    2000-01-01

    Transition radiation detectors show great promise for the purposes of lepton identification in existing and future experiments in high- energy physics such as HERA-B, ATLAS, ALICE in high-luminosity environment. More high performance can be expected in low-luminosity conditions-neutrino experiments (NOMAD), and the ideal condition for the use of transition radiation detectors in flying and space high- energy experiments (AMS). This paper discusses the practical theory of transition radiation, basic equation and algorithm suitable for detailed analysis of transition radiation and optimization of transition radiation detectors in the area of experimental high- energy physics. The results are based on detailed Monte Carlo simulation of transition radiation introduced in GEANT and experimental results. (12 refs).

  2. Deflection of high energy channeled charged particles by elastically bent silicon single crystals

    International Nuclear Information System (INIS)

    Gibson, W.M.; Kim, I.J.; Pisharodoy, M.; Salman, S.M.; Sun, C.R.; Wang, G.H.; Wijayawardana, R.; Forster, J.S.; Mitchell, I.V.; Baker, S.I.; Carrigan, R.A. Jr.; Toohig, T.E.; Avdeichikov, V.V.; Ellison, J.A.; Siffert, P.

    1984-01-01

    An experiment has been carried out to observe the deflection of charged particles by planar channeling in bent single crystals of silicon for protons with energy up to 180 GeV. Anomolous loss of particles from the center point of a three point bending apparatus was observed at high incident particle energy. This effect has been exploited to fashion a 'dechanneling spectrometer' to study dechanneling effects due to centripital displacement of channeled particle trajectories in a bent crystal. The bending losses generally conform to the predictions of calculations based on a classical model. (orig.)

  3. Physics of high energy particle accelerators. AIP conference proceedings No. 127

    International Nuclear Information System (INIS)

    Month, M.; Dahl, P.F.; Dienes, M.

    1985-01-01

    Topics covered in this workshop include accelerator physics, particle physics, and new acceleration methods. Eighteen lectures were presented. Individual abstracts were prepared separately for the data base

  4. High energy proton induced radiation damage of rare earth permanent magnet quadrupoles

    Science.gov (United States)

    Schanz, M.; Endres, M.; Löwe, K.; Lienig, T.; Deppert, O.; Lang, P. M.; Varentsov, D.; Hoffmann, D. H. H.; Gutfleisch, O.

    2017-12-01

    Permanent magnet quadrupoles (PMQs) are an alternative to common electromagnetic quadrupoles especially for fixed rigidity beam transport scenarios at particle accelerators. Using those magnets for experimental setups can result in certain scenarios, in which a PMQ itself may be exposed to a large amount of primary and secondary particles with a broad energy spectrum, interacting with the magnetic material and affecting its magnetic properties. One specific scenario is proton microscopy, where a proton beam traverses an object and a collimator in which a part of the beam is scattered and deflected into PMQs used as part of a diagnostic system. During the commissioning of the PRIOR (Proton Microscope for Facility for Antiproton and Ion Research) high energy proton microscope facility prototype at Gesellschaft für Schwerionenforschung in 2014, a significant reduction of the image quality was observed which was partially attributed to the demagnetization of the used PMQ lenses and the corresponding decrease of the field quality. In order to study this phenomenon, Monte Carlo simulations were carried out and spare units manufactured from the same magnetic material—single wedges and a fully assembled PMQ module—were deliberately irradiated by a 3.6 GeV intense proton beam. The performed investigations have shown that in proton radiography applications the above described scattering may result in a high irradiation dose in the PMQ magnets. This did not only decrease the overall magnetic strength of the PMQs but also caused a significant degradation of the field quality of an assembled PMQ module by increasing the parasitic multipole field harmonics which effectively makes PMQs impractical for proton radiography applications or similar scenarios.

  5. Intercomparison of radiation protection devices in a high-energy stray neutron field, Part II: Bonner sphere spectrometry

    International Nuclear Information System (INIS)

    Wiegel, B.; Agosteo, S.; Bedogni, R.; Caresana, M.; Esposito, A.; Fehrenbacher, G.; Ferrarini, M.; Hohmann, E.; Hranitzky, C.; Kasper, A.; Khurana, S.; Mares, V.; Reginatto, M.; Rollet, S.; Ruehm, W.; Schardt, D.; Silari, M.; Simmer, G.; Weitzenegger, E.

    2009-01-01

    The European Commission has funded within its 6th Framework Programme a three-year project (2005-2007) called CONRAD, COordinated Network for RAdiation Dosimetry. A major task of the CONRAD Work Package 'complex mixed radiation fields at workplaces' was to organise a benchmark exercise in a workplace field at a high-energy particle accelerator where neutrons are the dominant radiation component. The CONRAD benchmark exercise took place at the Gesellschaft fuer Schwerionenforschung mbH (GSI) in Darmstadt, Germany in July 2006. In this paper, the results of the spectrometry using four extended -range Bonner sphere spectrometers of four different institutes are reported. Outside Cave A the neutron spectra were measured with three spectrometers at six selected positions and ambient dose equivalent values were derived for use in the intercomparison with other area monitors and dosemeters. At a common position all three spectrometers were used to allow a direct comparison of their results which acts as an internal quality assurance. The comparison of the neutron spectra measured by the different groups shows very good agreement. A detailed analysis presents some differences between the shapes of the spectra and possible sources of these differences are discussed. However, the ability of Bonner sphere spectrometers to provide reliable integral quantities like fluence and ambient dose equivalent is well demonstrated in this exercise. The fluence and dose results derived by the three groups agree very well within the given uncertainties, not only with respect to the total energy region present in this environment but also for selected energy regions which contribute in certain strength to the total values. In addition to the positions outside Cave A one spectrometer was used to measure the neutron spectrum at one position in the entry maze of Cave A. In this case a comparison was possible to earlier measurements.

  6. Use of specific features of electron and positron interactions with monocrystals for the control of high-energy particle beam parameters

    International Nuclear Information System (INIS)

    Bochek, G.L.; Vit'ko, V.I.; Grishaev, I.A.; Kovalenko, G.D.; Kulibaba, V.I.; Morokhovskij, V.L.; Shramenko, B.I.

    1977-01-01

    To study possibilities of using the effect of high energy positron and electron interactions with crystals in practice at the 2 GeV Kharkov lineac the effect of a light particle charge sign on the processes of bremsstrahlung, elastic scattering and revealing ''blocking effect'' in elastic scatterina has been investigated experimentally of 1 GeV electron (positron) beam is directed to a silicon crystal of 185 μkm thickness. Dependence of total bremsstrahlung flow on the angle between the beam direction and crystal axis has shown, that positron bremsstrahlung is minimum (positrons are channelling, but electron bremsstrahlung is maximum, when crystallographic axis direction coincides with particle direction. The process of positron annihilation in flight has been investigated in 300 μkm thick silicon monocrystal. Bremsstrahlung intensity for channeling positrons drops 4.4 times, and intensity of annihilation radiation - 1.6 times as compared to the case, when channeling regime is absent. Experimental data point out the possibility of using monocrystals for control of the parameters of high-energy particle control beams

  7. High-energy synchrotron radiation x-ray microscopy: Present status and future prospects

    International Nuclear Information System (INIS)

    Jones, K.W.; Gordon, B.M.; Spanne, P.; Rivers, M.L.; Sutton, S.R.

    1991-01-01

    High-energy radiation synchrotron x-ray microscopy is used to characterize materials of importance to the chemical and materials sciences and chemical engineering. The x-ray microscope (XRM) forms images of elemental distributions fluorescent x rays or images of mass distributions by measurement of the linear attenuation coefficient of the material. Distributions of sections through materials are obtained non-destructively using the technique of computed microtomography. The energy range of the x rays used for the XRM ranges from a few keV at the minimum value to more than 100 keV, which is sufficient to excite the K-edge of all naturally occurring elements. The work in progress at the Brookhaven NSLS X26 and X17 XRM is described in order to show the current status of the XRM. While there are many possible approaches to the XRM instrumentation, this instrument gives state-of-the-art performance in most respects and serves as a reasonable example of the present status of the instrumentation in terms of the spatial resolution and minimum detection limits obtainable. The examples of applications cited give an idea of the types of research fields that are currently under investigation. They can be used to illustrate how the field of x-ray microscopy will benefit from the use of bending magnets and insertion devices at the Advanced Photon Source. 8 refs., 5 figs

  8. High-energy synchrotron radiation x-ray microscopy: Present status and future prospects

    International Nuclear Information System (INIS)

    Jones, K.W.; Gordon, B.M.; Spanne, P.; Rivers, M.L.; Sutton, S.R.

    1991-01-01

    High-energy radiation synchrotron x-ray microscopy is used to characterize materials of importance to the chemical and materials sciences and chemical engineering. The x-ray microscope (XRM) forms images of elemental distributions fluorescent x rays or images of mass distributions by measurement of the linear attenuation coefficient of the material. Distributions of sections through materials are obtained non-destructively using the technique of computed microtomography (CMT). The energy range of the x rays used for the XRM ranges from a few keV at the minimum value to more than 100 keV, which is sufficient to excite the K-edge of all naturally occurring elements. The work in progress at the Brookhaven NSLS X26 and X17 XRM is described in order to show the current status of the XRM. While there are many possible approaches to the XRM instrumentation, this instrument gives state-of-the-art performance in most respects and serves as a reasonable example of the present status of the instrumentation in terms of the spatial resolution and minimum detection limits (MDLs) obtainable. The examples of applications cited give an idea of the types of research fields that are currently under investigation. They can be used to illustrate how the field of x-ray microscopy will benefit from the use of bending magnets and insertion devices at the Advanced Photon Source (APS)

  9. Status report of the Cornell High Energy Synchrotron Radiation Source (CHESS)

    International Nuclear Information System (INIS)

    Batterman, B.W.

    1980-01-01

    The Wilson Laboratory at Cornell University has done pioneering work on the development of high energy synchrotrons. In the last decade the 12 GeV Wilson Synchrotron was the most energetic electron synchrotron in the world. In 1975 plans were formulated at the Wilson Laboratory to build a new electron-positron storage ring to cover the range from 4-8 GeV. The storage ring was to be constructed in the same tunnel as the present synchrotron and to use the latter as an injector for the ring. A novel injection feature was to be incorporated, namely, vernier phase compression. In this scheme, positron coalesence is to be performed by compressing a 30-60 bunch positron beam by tranferring individual bunches from the storage ring to the synchrotron and stacking back into the storage ring. This procedure takes advantage of the slight circumferential difference between the storage ring and the synchrotron. Positron beams of 10 mA have been achieved in CESR at the present time. The first colliding beam studies were performed in an October 1979 two-week running period at which time CHESS, the synchrotron radiation source associated with CESR, also had its first extended experience with synchrotron light. (orig.)

  10. Thundercloud electrodynamics and its influence on high-energy radiation enhancements and lightning initiation

    International Nuclear Information System (INIS)

    Mareev, E.A.; Iudin, D.I.; Rakov, V.A.; Kostinskiy, A.Yu.; Syssoev, V.S.

    2016-01-01

    We analyze multi-scale dynamics of thunderstorm electric structure as related to high-energy radiation enhancements and lightning initiation. First, we review experimental data on the multi-layer charge structure of thunderstorm clouds. A special attention is paid to the lower positive charge region (LPCR) and its possible effects on the development of CG and IC discharges and thunderstorm ground enhancements (TGEs). Based on the graph theory, we have developed a fractal simulation code to examine the occurrence of lightning flashes of different type as a function of the cloud charge structure. We show in particular that presence of relatively intense lower positive charge region prevents the occurrence of negative CG flashes by ”blocking” the progression of descending negative leader from reaching ground. Further, based on our recent observations of electrical discharges in the artificial cloud of charged water droplets, we present the description of a complex hierarchical network of interacting channels at different stages of development (some of which are hot and live for milliseconds), which can possibly be considered as a missing link in the still poorly understood lightning initiation process. (author)

  11. RFLP analysis of rice semi-dwarf mutation induced by high energy argon ion radiation

    International Nuclear Information System (INIS)

    Zhuang Chuxiong; Hu Weimin; Mei Mantong

    1997-01-01

    Two Indica rice varieties, Bianpizhan and Xiangzhan, and their semi-dwarf mutants induced by high energy argon ion radiation, Ar-10, and Xiang-Ar-1, were examined with restriction fragment length polymorphism (RFLP) analysis by using 97 rice single copy genomic clones mapped on 12 chromosomes of molecular genetic map, combined with 5 restriction enzymes. Among the markers screened, 9 detected polymorphism were between Bianpizhen and Ar-10, and 11 detected polymorphism were between Xiangzhan and Xiang-Ar-1. Moreover, two or more restriction enzymes could generate RFLP patterns when screened with a given marker for several polymorphic markers. Based on the polymorphic allelic loci, the mutation frequencies were estimated as 5.15% and 6.39% for Ar-10 and Xiang-Ar-1 respectively. These results suggested that the nature of mutation on the DNA level was probably large genetic changes rather than point mutation. Genetic analysis and gene tagging of semi-dwarf mutation in one of the mutant line, Ar-10, indicated that this mutation was controlled by a major recessive gene, which was preliminary located on chromosome 4

  12. RFLP Analysis of rice semi dwarf mutation induced by high energy argon ion radiation

    International Nuclear Information System (INIS)

    Zhuang Chuxiong; Hu Weimin; Mei Mantong

    1997-01-01

    Two Indica rice varieties, Bianpizhan and Xiangzhan, and their semi dwarf mutants induced by high energy argon ion radiation, Ar 10, and Xiang Ar 1, were examined with restriction fragment length polymorphism(RFLP)analysis by using 97 rice single copy genomic clones mapped on 12 chromosomes of molecular genetic map, combined with 5 restriction enzymes.Among the markers screened, 9 detected polymorphism were between Bianpizhan and Ar 10, and 11 detected polymorphism were between Xiangzhan and Xiang Ar 1.Moreover, two or more restriction enzymes could generate RFLP patterns when screened with a given marker for several polymorphic markers. Based on the polymorphic allelic loci, the mutation frequencies were estimated as 5 15% and 6 39% for Ar 10 and Xiang Ar 1 respectively.These results suggested that the nature of mutation on the DNA level was probably large genetic changes rather than point mutation.Genetic analysis and gene tagging of semi dwarf mutation in one of the mutant line, Ar 10, indicated that this mutation was controlled by a major recessive gene, which was preliminary located on chromosome 4. (author)

  13. Examining the High-energy Radiation Mechanisms of Knots and Hotspots in Active Galactic Nucleus Jets

    Science.gov (United States)

    Zhang, Jin; Du, Shen-shi; Guo, Sheng-Chu; Zhang, Hai-Ming; Chen, Liang; Liang, En-Wei; Zhang, Shuang-Nan

    2018-05-01

    We compile the radio–optical–X-ray spectral energy distributions (SEDs) of 65 knots and 29 hotspots in 41 active galactic nucleus jets to examine their high-energy radiation mechanisms. Their SEDs can be fitted with the single-zone leptonic models, except for the hotspot of Pictor A and six knots of 3C 273. The X-ray emission of 1 hotspot and 22 knots is well explained as synchrotron radiation under the equipartition condition; they usually have lower X-ray and radio luminosities than the others, which may be due to a lower beaming factor. An inverse Compton (IC) process is involved for explaining the X-ray emission of the other SEDs. Without considering the equipartition condition, their X-ray emission can be attributed to the synchrotron-self-Compton process, but the derived jet powers (P jet) are not correlated with L k and most of them are larger than L k, with more than three orders of magnitude, where L k is the jet kinetic power estimated with their radio emission. Under the equipartition condition, the X-ray emission is well interpreted with the IC process for the cosmic microwave background photons (IC/CMB). In this scenario, the derived P jet of knots and hotspots are correlated with and comparable to L k. These results suggest that the IC/CMB model may be a promising interpretation of the X-ray emission. In addition, a tentative knot–hotspot sequence in the synchrotron peak-energy–peak-luminosity plane is observed, similar to the blazar sequence, which may be attributed to the different cooling mechanisms of electrons.

  14. High-energy kink in the single-particle spectra of cuprates

    Energy Technology Data Exchange (ETDEWEB)

    Cojocaru, S. [Dipartimento di Fisica ' E. R. Caianiello' and C.N.I.S.M., Universita degli Studi di Salerno, Via S. Allende, I-84081 Baronissi (Italy); Institute of Applied Physics, Chisinau 2028 (Moldova, Republic of); Citro, R. [Dipartimento di Fisica ' E. R. Caianiello' and C.N.I.S.M., Universita degli Studi di Salerno, Via S. Allende, I-84081 Baronissi (Italy)], E-mail: citro@sa.infn.it; Marinaro, M. [Dipartimento di Fisica ' E. R. Caianiello' and C.N.I.S.M., Universita degli Studi di Salerno, Via S. Allende, I-84081 Baronissi (Italy); I.I.A.S.S., Via G. Pellegrino, n. 19 84019 Vietri sul Mare (Italy)

    2008-04-01

    Within a phenomenological model where electrons are coupled to a bosonic mode in a generic form of damped oscillator, we analyze the high-energy kink recently observed in ARPES experiments on cuprates. It is shown that the model allows to describe the main anomalous features found in experiments, such as the broad incoherent spectral weight, the 'waterfall dispersion', its doping and temperature dependence. In contrast to the low-energy kink, presence of significant damping is required to account for the anomalies. The 'bosonic mode' is related to the incoherent excitation peak observed in optical conductivity spectra of cuprates.

  15. High-energy kink in the single-particle spectra of cuprates

    International Nuclear Information System (INIS)

    Cojocaru, S.; Citro, R.; Marinaro, M.

    2008-01-01

    Within a phenomenological model where electrons are coupled to a bosonic mode in a generic form of damped oscillator, we analyze the high-energy kink recently observed in ARPES experiments on cuprates. It is shown that the model allows to describe the main anomalous features found in experiments, such as the broad incoherent spectral weight, the 'waterfall dispersion', its doping and temperature dependence. In contrast to the low-energy kink, presence of significant damping is required to account for the anomalies. The 'bosonic mode' is related to the incoherent excitation peak observed in optical conductivity spectra of cuprates

  16. Theoretical aspects of effects of high-energy particles on MHD modes

    International Nuclear Information System (INIS)

    Villard, L.; Brunner, S.; Vaclavik, J.

    1994-01-01

    In this paper we adopt a global approach. The TAEs are computed globally in true toroidal geometry consistent with an ideal MHD equilibrium. Kinetic effects (damping and driving mechanisms) and fast particles are treated perturbatively. More precisely, we first obtain the global eigenmodes an then use these given eigenmode fields to evaluate the global overall wave-particle power transfer assuming given fast particle density profiles. The marginal stability point is obtained by scaling the number of fast particles so that the overall power transfer is zero. The wave-particle power transfers are evaluated using the drift-kinetic equations. The paper is structured as follows: In section two, the plasma model in toroidal geometry is briefly presented. The expressions for the DKE powers are derived for the various species in the companion paper in these proceedings. In section 3 we show the results of our model applied to a wide variety of plasma parameters. In particular, the critical volume-averaged fast particle beta corresponding to marginal stability, f > cr , is calculated for a wide range of bulk plasma parameters and fast particle profile widths. We discuss the results in section 4 and draw some conclusions in section 5.(author) 13 figs., 21 refs

  17. Hard scattering contribution to particle production in high energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Pareek, Pooja; Mishra, Aditya Nath; Sahoo, Pragati; Sahoo, Raghunath

    2014-01-01

    Global observables like the multiplicity of produced charged particles and transverse energy, are the key observables used to characterize the properties of the matter created in heavy-ion collisions. In order to study the dependence of the charged particle density on colliding system, center of mass energy and collision centrality, there have been measurements starting few GeV to TeV energies at LHC. There is a need to understand the particle production contribution coming from the QCD hard processes, which scale with number of binary nucleon-nucleon collisions, N coll and soft processes scaling with number of participant nucleons, N part

  18. Radiations effects on polymeric materials used in CERN particles accelerators

    International Nuclear Information System (INIS)

    Tavlet, M.

    1997-01-01

    For fundamental research on the basis structure of matter, the European Organization for Nuclear Research (CERN) operates several high-energy particle accelerators around which materials and components are exposed to ionizing radiation. To ensure a safe and reliable operation, the radiation behaviour of most of the components is systematically tested prior to their selection. The long-term radiation-test programme allows to assess the component lifetime in the environment or our accelerators where the absorbed doses are continuously recorded. This article presents organic materials in use at CERN, and some recent results are given on their behaviour under irradiation. (authors)

  19. Investigations of percutaneous uptake of ultrafine TiO{sub 2} particles at the high energy ion nanoprobe LIPSION

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, F. E-mail: fmenzel@physik.uni-leipzig.de; Reinert, T.; Vogt, J.; Butz, T

    2004-06-01

    Micronised TiO{sub 2} particles with a diameter of about 15 nm are used in sunscreens as physical UV filter. Due to the small particle size it may be supposed that TiO{sub 2} particles can pass through the uppermost horny skin layer (stratum corneum) via intercellular channels and penetrate into deeper vital skin layers. Accumulations of TiO{sub 2} particles in the skin can decrease the threshold for allergies of the immune system or cause allergic reactions directly. Spatially resolved ion beam analysis (PIXE, RBS, STIM and secondary electron imaging) was carried out on freeze-dried cross-sections of biopsies of pig skin, on which four different formulations containing TiO{sub 2} particles were applied. The investigations were carried out at the high energy ion nanoprobe LIPSION in Leipzig with a 2.25 MeV proton beam, which was focused to a diameter of 1 {mu}m. The analysis concentrated on the penetration depth and on pathways of the TiO{sub 2} particles into the skin. In these measurements a penetration of TiO{sub 2} particles through the s. corneum into the underlying stratum granulosum via intercellular space was found. Hair follicles do not seem to be important penetration pathways because no TiO{sub 2} was detected inside. The TiO{sub 2} particle concentration in the stratum spinosum was below the minimum detection limit of about 1 particle/{mu}m{sup 2}. These findings show the importance of coating the TiO{sub 2} particles in order to prevent damage of RNA and DNA of skin cells by photocatalytic reactions of the penetrated particles caused by absorption of UV light.

  20. Investigations of percutaneous uptake of ultrafine TiO2 particles at the high energy ion nanoprobe LIPSION

    International Nuclear Information System (INIS)

    Menzel, F.; Reinert, T.; Vogt, J.; Butz, T.

    2004-01-01

    Micronised TiO 2 particles with a diameter of about 15 nm are used in sunscreens as physical UV filter. Due to the small particle size it may be supposed that TiO 2 particles can pass through the uppermost horny skin layer (stratum corneum) via intercellular channels and penetrate into deeper vital skin layers. Accumulations of TiO 2 particles in the skin can decrease the threshold for allergies of the immune system or cause allergic reactions directly. Spatially resolved ion beam analysis (PIXE, RBS, STIM and secondary electron imaging) was carried out on freeze-dried cross-sections of biopsies of pig skin, on which four different formulations containing TiO 2 particles were applied. The investigations were carried out at the high energy ion nanoprobe LIPSION in Leipzig with a 2.25 MeV proton beam, which was focused to a diameter of 1 μm. The analysis concentrated on the penetration depth and on pathways of the TiO 2 particles into the skin. In these measurements a penetration of TiO 2 particles through the s. corneum into the underlying stratum granulosum via intercellular space was found. Hair follicles do not seem to be important penetration pathways because no TiO 2 was detected inside. The TiO 2 particle concentration in the stratum spinosum was below the minimum detection limit of about 1 particle/μm 2 . These findings show the importance of coating the TiO 2 particles in order to prevent damage of RNA and DNA of skin cells by photocatalytic reactions of the penetrated particles caused by absorption of UV light

  1. High energy particles with negative and positive energies in the vicinity of black holes

    Science.gov (United States)

    Grib, A. A.; Pavlov, Yu. V.

    2014-07-01

    It is shown that the energy in the centre of mass frame of two colliding particles in free fall at any point of the ergosphere of the rotating black hole can grow without limit for fixed energy values of particles on infinity. The effect takes place for large negative values of the angular momentum of one of the particles. It occurs that the geodesics with negative energy in equatorial plane of rotating black holes cannot originate or terminate inside the ergosphere. Their length is always finite and this leads to conclusion that they must originate and terminate inside the gravitational radius of the ergosphere. The energy in the centre of mass frame of one particle falling into the gravitational radius and the other arriving from the area inside it is growing without limit on the horizon.

  2. What could we learn about high energy particle physics from cosmological observations at largest spatial scales ?

    Directory of Open Access Journals (Sweden)

    Gorbunov Dmitry

    2017-01-01

    Full Text Available The very well known example of cosmology testing particle physics is the number of relativistic particles (photons and three active neutrinos within the Standard Model at primordial nucleosynthesis. These days the earliest moment we can hope to probe with present cosmological data is the early time inflation. The particle physics conditions there and now are different because of different energy scales and different values of the scalar fields, that usually prohibits a reliable connection between the particle physics parameters at the two interesting epochs. The physics at the highest energy scales may be probed with observations at the largest spatial scales (just somewhat smaller than the size of the visible Universe. However, we are not (yet ready to make the tests realistic, because of lack of a self-consistent theoretical description of the presently favorite cosmological models to be valid right after inflation.

  3. Three particle scattering at high energies in a model with eikonal Hamiltonian

    International Nuclear Information System (INIS)

    Kharchenko, V.F.; Kuzmichev, V.E.

    1980-04-01

    The three particle collision process 3 → 3 with relative motion of each pair of particles described by a model with eikonal Hamiltonian is investigated. No additional restrictions on the motion of the particles (such as the fixed scattering centre approximation) are imposed. A unique, exact analytical solution of the three-particle problem is then shown to exist. An explicit expression for the 3 → 3 amplitude in the general case off the energy shell is obtained as the result of the exact summation of the multiple scattering series. It is shown that this series terminates on the energy shell. A new formula for the mutual cancellation of terms in the multiple scattering series in a model with eikonal Hamiltonian is found. (orig.)

  4. Particle physics explanations for ultra-high energy cosmic ray events

    Indian Academy of Sciences (India)

    this talk I briefly summarize several proposed particle physics explanations: a breakdown ... as primaries, and magnetic monopoles with mass below 1010 GeV as primaries. .... these monopoles would be the ultimate test of this explanation.

  5. Coordinate determination of high energy charged particles by silicon strip detectors

    International Nuclear Information System (INIS)

    Anokhin, I.E.; Zinets, O.S.

    2002-01-01

    The coordinate determination accuracy of minimum ionizing and short-range particles by silicon strip detectors has been considered. The charge collection on neighboring strips of the detector is studied and the influence of diffusion and the electric field distribution on the accuracy of the coordinate determination is analyzed. It has been shown that coordinates of both minimum ionizing and short-range particles can be determined with accuracy to a few microns using silicon strip detectors. 11 refs.; 8 figs

  6. U.C. Davis high energy particle physics research: Technical progress report -- 1990

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-12-31

    Summaries of progress made for this period is given for each of the following areas: (1) Task A--Experiment, H1 detector at DESY; (2) Task C--Experiment, AMY detector at KEK; (3) Task D--Experiment, fixed target detectors at Fermilab; (4) Task F--Experiment, PEP detector at SLAC and pixel detector; (5) Task B--Theory, particle physics; and (6) Task E--Theory, particle physics.

  7. Effect of high energy β-radiation and addition of triallyl isocyanurate on the selected properties of polylactide

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, Rafał, E-mail: malinowskirafal@gmail.com

    2016-06-15

    Comparison of some changes occurring in polylactide (PLA) due to high energy β-radiation and addition of triallyl isocyanurate (TAIC) was the main objective of the present study. It was found that irradiation of PLA by high energy β-radiation causes essential changes in its properties, that undergoes mainly degradation, to form a porous structure. The PLA degradation can be diminished by introduction into the polymer matrix of a low-molecular mass multifunctional compound like TAIC. Upon the electron radiation, effective crosslinking of PLA by TAIC occurs. Application of TAIC favorably influences hindering of the PLA degradation or, when the doses are very large, diminishes worsening of the PLA functional qualities. It was also found that the optimum crosslinking of PLA is obtained when the electron radiation doses of the range of 40–200 kGy are applied and the amount of TAIC equal 3–5 wt% is used.

  8. MnBi particles with high energy density made by spark erosion

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Phi-Khanh, E-mail: phi@ucsd.edu; Jin, Sungho [Materials Science and Engineering, University of California, San Diego, La Jolla, California 92093 (United States); Center for Magnetic Recording Research, University of California, San Diego, La Jolla, California 92093 (United States); Berkowitz, Ami E. [Physics Department, University of California, San Diego, La Jolla, California 92093 (United States); Center for Magnetic Recording Research, University of California, San Diego, La Jolla, California 92093 (United States)

    2014-05-07

    We report on the properties of low-temperature phase (LTP)-MnBi particles produced by the rapid-quenching technique of spark-erosion. The as-prepared powder consists of amorphous, crystalline, and superparamagnetic particles, mostly as porous aggregates. The major fraction of the powder consists of 20–30 nm particles. A short anneal crystallizes the amorphous particles producing a high moment, >90% of theoretical M{sub S}, albeit with H{sub C} of a few kOe. If lightly milled, the agglomerates are broken up to yield H{sub C} of 1 T. These findings are supported by the x-ray diffraction pattern showing broadened peaks of the predominant LTP-MnBi phase. The combination of spark erosion, milling, and annealing has produced randomly oriented particles with (BH){sub MAX} ∼ 3.0 MGOe. The particles are expected to show record energy product when aligned along their crystallographic easy axes.

  9. High energy scattering phenomena in the accelerators and colliders, and a study in the role of the 'leading particle effect' on the multiplicity of particles

    International Nuclear Information System (INIS)

    Bhattacharya, S.

    1989-01-01

    The role of the leading particles in high energy scattering phenomena has assumed much importance in recent times but it has not been duly considered in some theoretical studies. This oversight is pointed out, and some other shortcomings and insufficiencies of most of the contemporary theoretical studies not only from considerations of the leading particle effect (LPE) but also from some other viewpoints are mentio ned. A revised comparative study on the behaviour of the average multiplicity by taking into account some of the competing theoretical models and the influence of the leading particle effect on them is also presented. (author). 33 refs

  10. Applications of Robust, Radiation Hard AlGaN Optoelectronic Devices in Space Exploration and High Energy Density Physics

    Energy Technology Data Exchange (ETDEWEB)

    Sun, K.

    2011-05-04

    This slide show presents: space exploration applications; high energy density physics applications; UV LED and photodiode radiation hardness; UV LED and photodiode space qualification; UV LED AC charge management; and UV LED satellite payload instruments. A UV LED satellite will be launched 2nd half 2012.

  11. Theory of elementary particles and accelerator theory: Task C: Experimental high energy physics

    International Nuclear Information System (INIS)

    Brau, J.E.

    1992-01-01

    The experimental high energy physics group at the University of Oregon broadened its effort during the past year. The SLD effort extends from maintaining and operating the SLD luminosity monitor which was built at Oregon, to significant responsibility in physics analysis, such as event selection and background analysis for the left-right asymmetry measurement. The OPAL work focussed on the luminosity monitor upgrade to a silicon-tungsten calorimeter. Building on the work done at Oregon for SLD, the tungsten for this upgrade was machined by the Oregon shops and shipped to CERN for assembly. The Oregon GEM effort now concentrates on tracking, specifically silicon tracking. Oregon also has developed a silicon strip preradiator prototype, and tested it in a Brookhaven beam

  12. High Energy Density Laboratory Astrophysics

    CERN Document Server

    Lebedev, Sergey V

    2007-01-01

    During the past decade, research teams around the world have developed astrophysics-relevant research utilizing high energy-density facilities such as intense lasers and z-pinches. Every two years, at the International conference on High Energy Density Laboratory Astrophysics, scientists interested in this emerging field discuss the progress in topics covering: - Stellar evolution, stellar envelopes, opacities, radiation transport - Planetary Interiors, high-pressure EOS, dense plasma atomic physics - Supernovae, gamma-ray bursts, exploding systems, strong shocks, turbulent mixing - Supernova remnants, shock processing, radiative shocks - Astrophysical jets, high-Mach-number flows, magnetized radiative jets, magnetic reconnection - Compact object accretion disks, x-ray photoionized plasmas - Ultrastrong fields, particle acceleration, collisionless shocks. These proceedings cover many of the invited and contributed papers presented at the 6th International Conference on High Energy Density Laboratory Astrophys...

  13. Correlations between high momentum particles in proton-proton collisions at high energies

    International Nuclear Information System (INIS)

    Bobbink, G.J.

    1981-01-01

    This thesis describes an experiment performed at the CERN Intersecting Storage Rings. The experiment studies the reaction p+p→h 1 +h 2 +X at two centre-of-mass energies, √s=44.7 GeV and √s=62.3 GeV. Two of the outgoing particles (h 1 and h 2 ) are detected in opposite c.m.s. hemispheres at small polar angles with respect to the direction of two incident protons. The remaining particles produced (X) are not detected. The hadrons hsub(i) are identified mesons (π + , π - , K + , K - ) or baryons (p, Λ) with relatively large longitudinal psub(L) and small transverse momentum psub(T). The aim of the experiment is twofold. The first aim is to study whether the momentum distributions of the fast particles hsub(i) are correlated and thereby to constrain the possible interaction mechanisms responsible for the production of high psub(L), low psub(T) particles. The second aim is to establish to what extent the production of pions and kaons in inclusive proton-proton collisions (e.g. p+p→π+X, X=all other particles) resembles the production of pions and kaons in diffractive proton-proton collisions (e.g. p+p→p+π+X, in which the final-state proton has a momentum close to its maximum possible value). (Auth.)

  14. Some problems of the detection of the high energy gamma-radiation in space

    Science.gov (United States)

    Fradkin, M. I.; Ginzburg, V. L.; Kurnosova, L. V.; Labensky, A. G.; Razorenov, L. A.; Rusakovich, M. A.; Topchiev, N. P.; Kaplin, V. A.; Runtso, M. F.; Gorchakov, E. V.; Ignatiev, P. P.

    1995-05-01

    Diffuse gamma radiation in the Galaxy has been measured with instruments onboard the COS-B and Compton Gamma Ray Observatory (CGRO) satellites from the tens of keV up to about 30 GeV. There is no experimental data at higher energies, but this data is very important for the spectrum of primary cosmic rays and the existence of neutralinos (hypothetical supersymmetrical particles which are supposed to constitute dark matter in the Galaxy and create gamma-quanta in the process of annihilation). The GAMMA-400 collaboration is working on the design of a telescope for gamma-ray measurements in the 10-1000 GeV range. The electronics of the GAMMA-400 eliminate some hindering effects, in particular the influence of backscattered gammas emitted by the very massive calorimeter (calorimeter albedo). The GAMMA-400 project may be realized in the near future if economic conditions in Russia are favorable.

  15. Software tool for representation and processing of experimental data on high energy interactions of elementary particles

    International Nuclear Information System (INIS)

    Cherepanov, E.O.; Skachkov, N.B.

    2002-01-01

    The software tool is developed for detailed and evident displaying of information about energy and space distribution of secondary particles produced in the processes of elementary particles collisions. As input information the data on the components of 4-momenta of secondary particles is used. As for these data the information obtained from different parts of physical detector (for example, from the calorimeter or tracker) as well as the information obtained with the help of event generator is taken. The tool is intended for use in Windows operation system and is developed on the basis of Borland Delphi. Mathematical architecture of the software tool allows user to receive complete information without making additional calculations. The program automatically performs analysis of structure and distributions of signals and displays the results in a transparent form which allows their quick analysis. To display the information the three-dimensional graphic methods as well as colour decisions based on intuitive associations are also used. (author)

  16. Emission of high-energy charged particles at 00 in Ne-induced reactions

    International Nuclear Information System (INIS)

    Borcea, C.; Gierlik, E.; Kalinin, A.M.; Kalpakchieva, R.; Oganessia, Yu.Ts.; Pawlat, T.; Penionzhkevich, Yu.E.; Ryakhlyuk, A.V.

    1982-01-01

    Inclusive energy spectra have been measured for light charged particles emitted in the bombardment of 232 Th, 181 Ta, sup(nat)Ti and 12 C targets by 22 Ne ions at 178 MeV and sup(nat)Ti target by 20 Ne ions at 196 MeV. The reaction products were analysed and detected by means of a ΔE-E telescope placed in the focal plane of a magnetic spectrometer located at an angle of 0 deg with respect to the beam direction. In all the reactions studied light charged particles with an energy close to the respective calculated kinematic limit for a two-body exit channel are produced with relatively great probability. The results obtained make it possible to draw some conclusions about the reaction mechanism involving the emission of light charged particles

  17. Shower and Slow Particle Productions in Nucleus-Nucleus Collisions at High Energy

    International Nuclear Information System (INIS)

    Zayd, Hamdy M. M.; Rahim, Magda A.; Fakhraddin, S.

    2014-01-01

    The multiplicity distributions of shower, grey, and black particles produced in interactions of 4 He, 12 C, 16 O, 22 Ne, and 28 Si with emulsion (Em) at 4.1–4.5 A GeV/c beam energies, and their dependence on target groups (H, CNO, and AgBr) is presented and has been reproduced by multisource thermal model. The multiplicity and the angular distributions of the three types of particles have been investigated. The experimental results are compared with the corresponding ones from the model. We found that the experimental data agrees with theoretical calculations using multisource thermal model

  18. Practical neutron dosimetry at high energies

    International Nuclear Information System (INIS)

    McCaslin, J.B.; Thomas, R.H.

    1980-10-01

    Dosimetry at high energy particle accelerators is discussed with emphasis on physical measurements which define the radiation environment and provide an immutable basis for the derivation of any quantities subsequently required for risk evaluation. Results of inter-laboratory dosimetric comparisons are reviewed and it is concluded that a well-supported systematic program is needed which would make possible detailed evaluations and inter-comparisons of instruments and techniques in well characterized high energy radiation fields. High-energy dosimetry is so coupled with radiation transport that it is clear their study should proceed concurrently

  19. Particle production in very-high-energy cosmic-ray emulsion chamber events: Usual and unusual events

    International Nuclear Information System (INIS)

    Costa, C.G.S.; Halzen, F.; Salles, C.

    1995-01-01

    We show that a simple scaling model of very forward particle production, consistent with accelerator and air shower data, can describe the overall features of the very-high-energy interactions recorded with emulsion chambers. The rapidity and transverse momentum distribution of the secondaries are quantitatively reproduced. This is somewhat surprising after numerous claims that the same data implied large scaling violations or new dynamics. Interestingly, we cannot describe some of the Centauro events, suggesting that these events are anomalous independently of their well-advertised unusual features such as the absence of neutral secondaries

  20. Particle accelerators, colliders, and the story of high energy physics. Charming the cosmic snake

    International Nuclear Information System (INIS)

    Jayakumar, Raghavan

    2012-01-01

    The Nordic mythological Cosmic Serpent, Ouroboros, is said to be coiled in the depths of the sea, surrounding the Earth with its tail in its mouth. In physics, this snake is a metaphor for the Universe, where the head, symbolizing the largest entity - the Cosmos - is one with the tail, symbolizing the smallest - the fundamental particle. Particle accelerators, colliders and detectors are built by physicists and engineers to uncover the nature of the Universe while discovering its building blocks. ''Charming the Cosmic Snake'' takes the readers through the science behind these experimental machines: the physics principles that each stage of the development of particle accelerators helped to reveal, and the particles they helped to discover. The book culminates with a description of the Large Hadron Collider, one of the world's largest and most complex machines operating in a 27-km circumference tunnel near Geneva. That collider may prove or disprove many of our basic theories about the nature of matter. The book provides the material honestly without misrepresenting the science for the sake of excitement or glossing over difficult notions. The principles behind each type of accelerator is made accessible to the undergraduate student and even to a lay reader with cartoons, illustrations and metaphors. Simultaneously, the book also caters to different levels of reader's background and provides additional materials for the more interested or diligent reader. (orig.)

  1. Properties of potential eco-friendly gas replacements for particle detectors in high-energy physics

    Science.gov (United States)

    Saviano, G.; Ferrini, M.; Benussi, L.; Bianco, S.; Piccolo, D.; Colafranceschi, S.; KjØlbro, J.; Sharma, A.; Yang, D.; Chen, G.; Ban, Y.; Li, Q.; Grassini, S.; Parvis, M.

    2018-03-01

    Gas detectors for elementary particles require F-based gases for optimal performance. Recent regulations demand the use of environmentally unfriendly F-based gases to be limited or banned. This work studies properties of potential eco-friendly gas replacements by computing the physical and chemical parameters relevant for use as detector media, and suggests candidates to be considered for experimental investigation.

  2. Charged Particle, Photon Multiplicity, and Transverse Energy Production in High-Energy Heavy-Ion Collisions

    Directory of Open Access Journals (Sweden)

    Raghunath Sahoo

    2015-01-01

    Full Text Available We review the charged particle and photon multiplicities and transverse energy production in heavy-ion collisions starting from few GeV to TeV energies. The experimental results of pseudorapidity distribution of charged particles and photons at different collision energies and centralities are discussed. We also discuss the hypothesis of limiting fragmentation and expansion dynamics using the Landau hydrodynamics and the underlying physics. Meanwhile, we present the estimation of initial energy density multiplied with formation time as a function of different collision energies and centralities. In the end, the transverse energy per charged particle in connection with the chemical freeze-out criteria is discussed. We invoke various models and phenomenological arguments to interpret and characterize the fireball created in heavy-ion collisions. This review overall provides a scope to understand the heavy-ion collision data and a possible formation of a deconfined phase of partons via the global observables like charged particles, photons, and the transverse energy measurement.

  3. Particle accelerators, colliders, and the story of high energy physics. Charming the cosmic snake

    Energy Technology Data Exchange (ETDEWEB)

    Jayakumar, Raghavan

    2012-07-01

    The Nordic mythological Cosmic Serpent, Ouroboros, is said to be coiled in the depths of the sea, surrounding the Earth with its tail in its mouth. In physics, this snake is a metaphor for the Universe, where the head, symbolizing the largest entity - the Cosmos - is one with the tail, symbolizing the smallest - the fundamental particle. Particle accelerators, colliders and detectors are built by physicists and engineers to uncover the nature of the Universe while discovering its building blocks. ''Charming the Cosmic Snake'' takes the readers through the science behind these experimental machines: the physics principles that each stage of the development of particle accelerators helped to reveal, and the particles they helped to discover. The book culminates with a description of the Large Hadron Collider, one of the world's largest and most complex machines operating in a 27-km circumference tunnel near Geneva. That collider may prove or disprove many of our basic theories about the nature of matter. The book provides the material honestly without misrepresenting the science for the sake of excitement or glossing over difficult notions. The principles behind each type of accelerator is made accessible to the undergraduate student and even to a lay reader with cartoons, illustrations and metaphors. Simultaneously, the book also caters to different levels of reader's background and provides additional materials for the more interested or diligent reader. (orig.)

  4. Critical review of a quantitative study of a specialty in high energy particle physics

    International Nuclear Information System (INIS)

    White, D.H.; Sullivan, D.

    1980-01-01

    A review is made of the authors' series of quantitative, historical, and social studies of the weak interactions of elementary particles. A short intellectual history, the quantitative methodology, and a summary of the papers analyzing specific episodes in this field are presented. The social organization of the field is described, and an overall policy for resource management is discussed. 6 figures, 3 tables

  5. Particle accelerators, colliders, and the story of high energy physics charming the cosmic snake

    CERN Document Server

    Jayakumar, Raghavan

    2012-01-01

    The Nordic mythological Cosmic Serpent, Ouroboros, is said to be coiled in the depths of the sea, surrounding the Earth with its tail in its mouth. In physics, this snake is a metaphor for the Universe, where the head, symbolizing the largest entity – the Cosmos – is one with the tail, symbolizing the smallest – the fundamental particle. Particle accelerators, colliders and detectors are built by physicists and engineers to uncover the nature of the Universe while discovering its building blocks. “Charming the Cosmic Snake” takes the readers through the science behind these experimental machines: the physics principles that each stage of the development of particle accelerators helped to reveal, and the particles they helped to discover. The book culminates with a description of the Large Hadron Collider, one of the world’s largest and most complex machines operating in a 27-km circumference tunnel near Geneva. That collider may prove or disprove many of our basic theories about the nature of matt...

  6. Some interesting features of charged particles produced in high-energy hadron-emulsion collisions

    International Nuclear Information System (INIS)

    Khushnood, H.; Ansari, A.R.

    1990-01-01

    The emission characteristics of secondary charged particles produced in 400 GeV proton-emulsion interactions were compared with those obtained at other energies. The results revealed that the angular distribution of grey particles does not depend on the nature and energy of the projectile. The dependence of the average multiplicity of the grey, black, shower, and heavily ionizing tracks on the mass of the target nucleus (A) and the nature and energy of the projectiles are also examined. The ratio of the valance quarks in pions (π - ) and protons (p) was found to be almost equal to the ratio of the grey particles produced in π - -A and p-A collisions at the same energy. The values of the normalized moments of the multiplicity distributions of charged shower particles in different N h intervals were found to nearly the same. However, this value increased with increasing values of the moment index, K. Finally, the values of the normalized and central moments were almost equal for both p-p and p-A interactions

  7. The production of charmed particles in high-energy 16O-emulsion central interactions

    International Nuclear Information System (INIS)

    Aoki, S.; Hoshino, K.; Kitamura, H.; Kobayashi, M.; Kodama, K.; Miyanishi, M.; Nakamura, K.; Nakamura, M.; Nakanishi, S.; Niu, K.; Niwa, K.; Nomura, M.; Tajima, H.; Tsukagoshi, K.; Mazzoni, M.A.; Poulard, G.; Meddi, F.; Rosa, G.; Muciaccia, M.T.; Simone, S.; Nakazawa, K.; Tasaka, S.; Sato, Y.

    1989-01-01

    The production of charmed particles has been detected in 200 GeV per nucleon 16 O-emulsion central interactions. Their production cross section in elementary nucleon-nucleon processes has been estimated to be σ charm =[14.1±9.3(stat.) -8.4 +5.6 (syst.)]μb. (orig.)

  8. Type conversion by high-energy particles in Hg1-xCdxTe compounds

    International Nuclear Information System (INIS)

    Blanchard, C.; Favre, J.; Barbot, J.F.; Desoyer, J.C.; Toulemonde, M.; Konczykowski, M.; Le Scoul, D.; Dessus, J.L.

    1990-01-01

    p-type crystals of the ternary compounds Hg 1-x Cd x Te have been irradiated with high-energy ions and electrons. Electron-beam-induced current signals on xenon- and krypton-irradiated Hg 1-x Cd x Te show that n-type conversion, occurring all along the ion path, is related to the presence of mercury atoms. Resistivity and Hall measurements on carbon-, oxygen-, xenon- and electron-irradiated Hg 0.8 Cd 0.2 Te crystals allow us to determine the effective cross section for atomic displacement. We observe, for electron-irradiated samples, a saturation in carrier concentration interpreted as the pinning of the Fermi level at a resonant donor state 370 meV above the bottom of the conduction band. Comparison between ion and electron irradiations shows that electrically active produced defects are mainly due to atomic collisions. Additional reduction of defect production efficiency for xenon ions may be the onset of some energy transfer from electronic loss to target atoms

  9. Microstructures for high-energy x-ray and particle-imaging applications

    International Nuclear Information System (INIS)

    Ceglio, N.M.; Stone, G.F.; Hawryluk, A.M.

    1981-05-01

    Coded imaging techniques using thick, micro-Fresnel zone plates as coded apertures have been used to image x-ray emissions (2-20 keV) and 3.5 MeV Alpha particle emissions from laser driven micro-implosions. Image resolution in these experiments was 3-8 μm. Extension of this coded imaging capability to higher energy x-rays (approx. 100 keV) and more penetrating charged particles (e.g. approx. 15 MeV protons) requires the fabrication of very thick (50-200 μm), high aspect ratio (10:1), gold Fresnel zone plates with narrow linewidths (5-25 μm) for use as coded aperatures. A reactive ion etch technique in oxygen has been used to produce thick zone plate patterns in polymer films. The polymer patterns serve as electroplating molds for the subsequent fabrication of the free-standing gold zone plate structures

  10. Free-parameterless model of high energy particle collisions with atomic nuclei

    International Nuclear Information System (INIS)

    Strugalski, Z.

    1982-01-01

    In result of studies, it has been discovered that: a) Intensive emission of fast nucleons of kinetic energy from 20 to 400 MeV proceeds independently of the pion production process; b) The particle production in hadron-nucleon collisions is mediated by intermediate objects produced first in a 2 → 2 type endoergic reaction and decaying after lifetime tausub(g) > or approximately 10 - 22 s into commonly known resonances and particles; c) Inside of massive enough atomic nuclei quasi-onedimensional cascades of the intermediate objects can develop; d) A definite simple connection exists between the characteristics of the secondaries appearing in hadron-nucleus collision events and corresponding hadron-nucleon collision events, the target-nucleus size and the nucleon density distribution in it. The yield of the hadron-nucleus collisions is described in a convincing manner in terms of the hadron-nucleon collision data by means of simple formulas

  11. Moment-Preserving Computational Approach for High Energy Charged Particle Transport

    Science.gov (United States)

    2016-05-16

    posed, but with modified cross sections such that the resulting single-event Monte Carlo simulation is computationally efficient (minutes vs . days...configurations, which are all characteristics of real world applications. In other words , it is possible to simulate real, physical phenomena using charged...0 < 0.95) ~ 1 2() ≫ 1, (3) Demonstrating that scattering is highly forward peaked. Thus, the picture of charged particle interactions

  12. Scanned beams of high-energy charged particles and features of their collimation

    International Nuclear Information System (INIS)

    Zor'ko, K.I.; Kudoyarov, M.F.; Matyukov, A.V.; Mukhin, S.A.; Patrova, M.Ya.

    2007-01-01

    The coordinate distributions of the accelerated charged particle flux density that are simultaneously formed by sinusoidal scanning and collimation are analyzed. Under certain formation conditions, the edge portions of these distributions are shown to take a two-humped shape. The experimental data obtained are in good agreement with the calculation. Recommendations are made about practical use of these beams in view of the above effects [ru

  13. Space-time structure of particle production in high-energy heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Ohtsuka, Naohiko; Ohnishi, Akira [Hokkaido Univ., Sapporo (Japan); Nara, Yasushi; Maruyama, Tomoyuki

    1998-07-01

    Space-Time structure of freeze-out of produced particles in relativistic nucleus-nucleus collisions are studied in the framework of two different cascade models, either with or without higher baryonic resonances. While higher excited baryonic resonances do not influence the spatial source size of freeze-out point, the freeze-out time distribution is shifted to be later by these resonances. (author)

  14. Production of massless particles in collisions of strings at high energy

    International Nuclear Information System (INIS)

    Lipatov, L.N.

    1988-01-01

    The authors obtain explicit formulas (generalizing the Low-Gribov expressions) for the production amplitude of massless particles (gluons and gravitons) with low transverse momenta in the scattering of lower-mass excitations of open and closed strings. In the limit α' → 0 they reproduce the results of calculation of effective vertices for inelastic scattering amplitudes in multi-Regge kinematics in the Yang-Mills theory and in gravitation

  15. Permanent magnets for production and use of high energy particle beams

    International Nuclear Information System (INIS)

    Halbach, K.

    1985-03-01

    In the last few years, permanent magnet systems have begun to play a dominant role in the generation of synchrotron radiation and the operation of free electron lasers. Similarly, permanent magnets can lead to significant improvements of accelerators and systems that use them. The general conditions are discussed under which one can expect benefits from permanent magnets, and a number of specific applications will be described in detail

  16. Hadron production in high energy muon scattering. [Quark-parton model, 225 GeV, structure functions, particle ratios

    Energy Technology Data Exchange (ETDEWEB)

    Hicks, R.G.

    1978-01-01

    An experiment was performed to study muon-proton scattering at an incident energy of 225 GeV and a total effective flux of 4.3 x 10/sup 10/ muons. This experiment is able to detect charged particles in coincidence with the scattered muon in the forward hemisphere, and results are reported for the neutral strange particles K/sub s//sup 0/ and ..lambda../sup 0/ decaying into two charged particles. Within experimental limits the masses and lifetimes of these particles are consistent with previous measurements. The distribution of hadrons produced in muon scattering is determined, measuring momentum components parallel and transverse to the virtual photon direction, and these distributions are compared to other high energy experiments involving the scattering of pions, protons, and neutrinos from protons. Structure functions for hadron production and particle ratios are calculated. No azimuthal dependence is observed, and lambda production does not appear to be polarized. The physical significance of the results is discussed within the framework of the quark-parton model. 29 references.

  17. High-energy Gamma Rays from the Milky Way: Three-dimensional Spatial Models for the Cosmic-Ray and Radiation Field Densities in the Interstellar Medium

    Energy Technology Data Exchange (ETDEWEB)

    Porter, T. A.; Moskalenko, I. V. [W. W. Hansen Experimental Physics Laboratory and Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305 (United States); Jóhannesson, G., E-mail: tporter@stanford.edu [Science Institute, University of Iceland, IS-107 Reykjavik (Iceland)

    2017-09-01

    High-energy γ -rays of interstellar origin are produced by the interaction of cosmic-ray (CR) particles with the diffuse gas and radiation fields in the Galaxy. The main features of this emission are well understood and are reproduced by existing CR propagation models employing 2D galactocentric cylindrically symmetrical geometry. However, the high-quality data from instruments like the Fermi Large Area Telescope reveal significant deviations from the model predictions on few to tens of degrees scales, indicating the need to include the details of the Galactic spiral structure and thus requiring 3D spatial modeling. In this paper, the high-energy interstellar emissions from the Galaxy are calculated using the new release of the GALPROP code employing 3D spatial models for the CR source and interstellar radiation field (ISRF) densities. Three models for the spatial distribution of CR sources are used that are differentiated by their relative proportion of input luminosity attributed to the smooth disk or spiral arms. Two ISRF models are developed based on stellar and dust spatial density distributions taken from the literature that reproduce local near- to far-infrared observations. The interstellar emission models that include arms and bulges for the CR source and ISRF densities provide plausible physical interpretations for features found in the residual maps from high-energy γ -ray data analysis. The 3D models for CR and ISRF densities provide a more realistic basis that can be used for the interpretation of the nonthermal interstellar emissions from the Galaxy.

  18. Dose to radiation therapists from activation at high-energy accelerators used for conventional and intensity-modulated radiation therapy

    International Nuclear Information System (INIS)

    Rawlinson, J. Alan; Islam, Mohammad K.; Galbraith, Duncan M.

    2002-01-01

    The increased beam-on times which characterize intensity-modulated radiation therapy (IMRT) could lead to an increase in the dose received by radiation therapists due to induced activity. To examine this, gamma ray spectrometry was used to identify the major isotopes responsible for activation at a representative location in the treatment room of an 18 MV accelerator (Varian Clinac 21EX). These were found to be 28 Al, 56 Mn, and 24 Na. The decay of the dose rate measured at this location following irradiation was analyzed in terms of the known half-lives to yield saturation dose rates of 9.6, 12.4, and 6.2 μSv/h, respectively. A formalism was developed to estimate activation dose (μSv/week) due to successive patient irradiation cycles, characterized by the number of 18 MV fractions per week, F, the number of MU per fraction, M, the in-room time between fractions, t d (min), and the treatment delivery time t r ' (min). The results are represented by the sum of two formulas, one for the dose from 28 Al≅1.8x10 -3 F M (1-e -0.3t r ' )/t r ' and one for the dose from the other isotopes ≅1.1x10 -6 F 1.7 Mt d . For conventional therapy doses are about 60 μ Sv/week for an 18 MV workload of 60 000 MU/week. Irradiation for QA purposes can significantly increase the dose. For IMRT as currently practiced, lengthy treatment delivery times limit the number of fractions that can be delivered per week and hence limit the dose to values similar to those in conventional therapy. However for an IMRT regime designed to maximize patient throughput, doses up to 330 μSv/week could be expected. To reduce dose it is recommended that IMRT treatments should be delivered at energies lower than 18 MV, that in multienergy IMRT, high-energy treatments should be scheduled in the latter part of the day, and that equipment manufacturers should strive to minimize activation in the design of high-energy accelerators

  19. Description of charged particle multiplicity distribution in high energy strong interaction

    International Nuclear Information System (INIS)

    Qin Keyu

    1994-01-01

    With the assumption that the probability for n-charged particles production in hadron-hadron collision is Pn and proper choice of 1 , 2 , k and x in Pn, the true multiplicity distribution in full phase space can be described successfully at the centre of mass energy √S GeV. Using the experimental data of non singe-diffractive collisions between proton and antiproton at centre of mass energies of 200 and 900 GeV, the supposition has been examined and confirmed: it is very good to describe the facts. The theoretical bases of supposition were discussed

  20. Diffraction of radiation from channelled charged particles

    International Nuclear Information System (INIS)

    Baryshevskij, V.G.; Grubich, A.O.; Dubovskaya, I.Ya.

    1978-01-01

    An explicit expression for cross-section and radiation spectrum at diffraction is calculated. It is shown that photons emitted by channelled particles form a typical diffraction pattern which contains information about the crystal structure. It is also shown that the change of the longitudinal energy of the particle caused by the radiation braking becomes important when the particle energy is increased. (author)

  1. Universality of hadron jets in soft and hard particle interactions at high energies

    International Nuclear Information System (INIS)

    Baldin, A.M.; Didenko, L.A.; Grishin, V.G.; Kuznetsov, A.A.

    1985-01-01

    The hadron jet production in soft π - p- and cumulative π - pC-interactions at a 40 GeV/c momentum is studied. The collective characteristics of jets and the functions of the quark and diquark fragmentation into charged pions and neutral strange particles are analysed. The results obtained are compared with analogous data for e + e - - and ν(anti ν)p- interactions. The hadron jet properties are also studied using relativistic invariant variables - the squared relative 4-velocities b sub(ik).-(Psub(i)/msub(i)-Psub(k)sup(2)/msub(k) (where Psub(i), Psub(k) are 4-momenta of i-th and K-th particles and msub(i), msub(k) are their masses). The results obtained show that the quark (diquark) fragmentation proceed in a similar manner in soft hadron-hadron collisions, cumulative interactions on light nuclei, in e + e - -annihilation and deep inelastic ν(anti ν)p-scattering

  2. Analytical expressions for noise and crosstalk voltages of the High Energy Silicon Particle Detector

    Science.gov (United States)

    Yadav, I.; Shrimali, H.; Liberali, V.; Andreazza, A.

    2018-01-01

    The paper presents design and implementation of a silicon particle detector array with the derived closed form equations of signal-to-noise ratio (SNR) and crosstalk voltages. The noise analysis demonstrates the effect of interpixel capacitances (IPC) between center pixel (where particle hits) and its neighbouring pixels, resulting as a capacitive crosstalk. The pixel array has been designed and simulated in a 180 nm BCD technology of STMicroelectronics. The technology uses the supply voltage (VDD) of 1.8 V and the substrate potential of -50 V. The area of unit pixel is 250×50 μm2 with the substrate resistivity of 125 Ωcm and the depletion depth of 30 μm. The mathematical model includes the effects of various types of noise viz. the shot noise, flicker noise, thermal noise and the capacitive crosstalk. This work compares the results of noise and crosstalk analysis from the proposed mathematical model with the circuit simulation results for a given simulation environment. The results show excellent agreement with the circuit simulations and the mathematical model. The average relative error (AVR) generated for the noise spectral densities with respect to the simulations and the model is 12% whereas the comparison gives the errors of 3% and 11.5% for the crosstalk voltages and the SNR results respectively.

  3. High speed optical wireless data transmission system for particle sensors in high energy physics

    Science.gov (United States)

    Ali, W.; Corsini, R.; Ciaramella, E.; Dell'Orso, R.; Messineo, A.; Palla, F.

    2015-08-01

    High speed optical fiber or copper wire communication systems are frequently deployed for readout data links used in particle physics detectors. Future detector upgrades will need more bandwidth for data transfer, but routing requirements for new cables or optical fiber will be challenging due to space limitations. Optical wireless communication (OWC) can provide high bandwidth connectivity with an advantage of reduced material budget and complexity of cable installation and management. In a collaborative effort, Scuola Superiore Sant'Anna and INFN Pisa are pursuing the development of a free-space optical link that could be installed in a future particle physics detector or upgrade. We describe initial studies of an OWC link using the inner tracker of the Compact Muon Solenoid (CMS) detector as a reference architecture. The results of two experiments are described: the first to verify that the laser source transmission wavelength of 1550 nm will not introduce fake signals in silicon strip sensors while the second was to study the source beam diameter and its tolerance to misalignment. For data rates of 2.5 Gb/s and 10 Gb/s over a 10 cm working distance it was observed that a tolerance limit of ±0.25 mm to ±0.8 mm can be obtained for misaligned systems with source beam diameters of 0.38 mm to 3.5 mm, respectively.

  4. High-energy particle production in solar flares (SEP, gamma-ray and neutron emissions). [solar energetic particles

    Science.gov (United States)

    Chupp, E. L.

    1987-01-01

    Electrons and ions, over a wide range of energies, are produced in association with solar flares. Solar energetic particles (SEPs), observed in space and near earth, consist of electrons and ions that range in energy from 10 keV to about 100 MeV and from 1 MeV to 20 GeV, respectively. SEPs are directly recorded by charged particle detectors, while X-ray, gamma-ray, and neutron detectors indicate the properties of the accelerated particles (electrons and ions) which have interacted in the solar atmosphere. A major problem of solar physics is to understand the relationship between these two groups of charged particles; in particular whether they are accelerated by the same mechanism. The paper reviews the physics of gamma-rays and neutron production in the solar atmosphere and the method by which properties of the primary charged particles produced in the solar flare can be deduced. Recent observations of energetic photons and neutrons in space and at the earth are used to present a current picture of the properties of impulsively flare accelerated electrons and ions. Some important properties discussed are time scale of production, composition, energy spectra, accelerator geometry. Particular attention is given to energetic particle production in the large flare on June 3, 1982.

  5. Effect of free-particle collisions in high energy proton and pion-induced nuclear reactions

    International Nuclear Information System (INIS)

    Jacob, N.P. Jr.

    1975-07-01

    The effect of free-particle collisions in simple ''knockout'' reactions of the form (a,aN) and in more complex nuclear reactions of the form (a,X) was investigated by using protons and pions. Cross sections for the 48 Ti(p,2p) 47 Sc and the 74 Ge(p,2p) 73 Ga reactions were measured from 0.3 to 4.6 GeV incident energy. The results indicate a rise in (p,2p) cross section for each reaction of about (25 +- 3) percent between the energies 0.3 and 1.0 GeV, and are correlated to a large increase in the total free-particle pp scattering cross sections over the same energy region. Results are compared to previous (p,2p) excitation functions in the GeV energy region and to (p,2p) cross section calculations based on a Monte Carlo intranuclear cascade-evaporation model. Cross section measurements for (π/sup +-/, πN) and other more complex pion-induced spallation reactions were measured for the light target nuclei 14 N, 16 O, and 19 F from 45 to 550 MeV incident pion energy. These measurements indicate a broad peak in the excitation functions for both (π,πN) and (π,X) reactions near 180 MeV incident energy. This corresponds to the large resonances observed in the free-particle π + p and π - p cross sections at the same energy. Striking differences in (π,πN) cross section magnitudes are observed among the light nuclei targets. The experimental cross section ratio sigma(π - ,π - n)/sigma(π + ,πN) at 180 MeV is 1.7 +- 0.2 for all three targets. The experimental results are compared to previous pion and analogous proton-induced reactions, to Monte Carlo intranuclear cascade-evaporation calculations, and to a semi-classical nucleon charge exchange model. (108 references) (auth)

  6. The generation of high fields for particle acceleration to very high energies

    International Nuclear Information System (INIS)

    1985-01-01

    A Workshop organised by the CERN Accelerator School, the European Committee for Future Accelerators and the Istituto Nazionale di Fisica Nucleare was held at the Frascati laboratory of INFN during the last week of September 1984. Its purpose was to bring together an inter-disciplinary group of physicists to review ideas for the acceleration of particles to energies beyond those attainable in machines whose construction is underway, or is currently contemplated. These proceedings contain some of the material presented and discussed at the Workshop, comprising papers on topics such as: the free-electron-laser, the lasertron, wakefield accelerators, the laser excitation of droplet arrays, a switched-power linac, plasma beat-wave accelerators and the choice of basic parameters for linear colliders intended for the TeV energy region. (orig.)

  7. The transmission diffraction patterns of silicon implanted with high-energy α-particles

    International Nuclear Information System (INIS)

    Wieteska, K.; Wierzchowski, W.

    1995-01-01

    2 mm thick silicon wafers, implanted with 4.8 MeV α-particles are studied by means of transmission section topography and additionally by Lang and double-crystal methods. It was found that all three methods produced a negligible contrast in the symmetric transmission reflection apart from some fragments of the implanted area's boundaries. The interference fringes were observed in the case of asymmetric reflections. The asymmetric section topographs revealed distinct interference fringes, which cannot be explained in terms of simple bicrystal models. In particular, the curvature of these fringes may be interpreted as being due to the change in the implanted ion dose along the beam intersecting the crystal. Some features of the fringe pattern were reproduced by numerical integration of Takagi-Taupin equations. (author)

  8. Vacuum Simulations in High Energy Accelerators and Distribution Properties of Continuous and Discrete Particle Motions

    CERN Document Server

    Aichinger, Ida; Kersevan, Roberto

    The underlying thesis on mathematical simulation methods in application and theory is structured into three parts. The first part sets up a mathematical model capable of predicting the performance and operation of an accelerator’s vacuum system based on analytical methods. A coupled species-balance equation system describes the distribution of the gas dynamics in an ultra-high vacuum system considering impacts of conductance limitations, beam induced effects (ion-, electron-, and photon-induced de- sorption), thermal outgassing and sticking probabilities of the chamber materials. A new solving algorithm based on sparse matrix representations, is introduced and presents a closed form solution of the equation system. The model is implemented in a Python environment, named PyVasco, and is supported by a graphical user interface to make it easy available for everyone. A sensitivity analysis, a cross-check with the Test-Particle Monte Carlo simulation program Molflow+ and a comparison of the simulation results t...

  9. Elementary particles and high energy phenomena. Progress report, May 1974--April 1975

    International Nuclear Information System (INIS)

    Nauenberg, U.; Bartlett, D.F.

    1975-05-01

    The study of K 0 /sub L/(π 3 ) has now been published in final form. When compared with the matrix elements for the K + (π 3 ) evidence was found for parallel I = 1/2 parallel violation in the linear terms, but not in the quadratic. The data-taking phase of a measurement of K 0 /sub L/ → K 0 /sub S/ p and related reactions at SLAC were completed. The presence of neutrons in the beam permits one to study several new reactions. The apparatus for detecting tachyon monopoles was installed above the Fermilab 15' bubble chamber, and data-taking begun. No evidence yet found for these particles. The theoretical effort was devoted to supporting the kaon experiments and to the study of dynamical symmetry breaking and Higg's symmetry. One has also written two proposals for experiments at Fermilab. A list of publications is included. (U.S.)

  10. A radiation transfer model for the Milky Way: I. Radiation fields and application to high-energy astrophysics★

    Science.gov (United States)

    Popescu, C. C.; Yang, R.; Tuffs, R. J.; Natale, G.; Rushton, M.; Aharonian, F.

    2017-09-01

    We present a solution for the ultraviolet - submillimetre (submm) interstellar radiation fields (ISRFs) of the Milky Way (MW), derived from modelling COBE, IRAS and Planck maps of the all-sky emission in the near-, mid-, far-infrared and submm. The analysis uses the axisymmetric radiative transfer model that we have previously implemented to model the panchromatic spectral energy distributions (SEDs) of star-forming galaxies in the nearby universe, but with a new methodology allowing for optimization of the radial and vertical geometry of stellar emissivity and dust opacity, as deduced from the highly resolved emission seen from the vantage point of the Sun. As such, this is the first self-consistent model of the broad-band continuum emission from the MW. In this paper, we present model predictions for the spatially integrated SED of the MW as seen from the Sun, showing good agreement with the data, and give a detailed description of the solutions for the distribution of ISRFs, as well as their physical origin, throughout the volume of the galaxy. We explore how the spatial and spectral distributions of our new predictions for the ISRF in the MW affects the amplitude and spectral distributions of the gamma rays produced via inverse Compton scattering for cosmic ray (CR) electrons situated at different positions in the galaxy, as well as the attenuation of the gamma rays due to interactions of the gamma-ray photons with photons of the ISRF. We also compare and contrast our solutions for the ISRF with those incorporated in the galprop package used for modelling the high-energy emission from CR in the MW.

  11. Total cross-sections for reactions of high energy particles (including elastic, topological, inclusive and exclusive reactions). Subvol. b

    International Nuclear Information System (INIS)

    Schopper, H.; Moorhead, W.G.; Morrison, D.R.O.

    1988-01-01

    The aim of this report is to present a compilation of cross-sections (i.e. reaction rates) of elementary particles at high energy. The data are presented in the form of tables, plots and some fits, which should be easy for the reader to use and may enable him to estimate cross-sections for presently unmeasured energies. We have analyzed all the data published in the major Journals and Reviews for momenta of the incoming particles larger than ≅ 50 MeV/c, since the early days of elementary particle physics and, for each reaction, we have selected the best cross-section data available. We have restricted our attention to integrated cross-sections, such as total cross-sections, exclusive and inclusive cross-sections etc., at various incident beam energies. We have disregarded data affected by geometrical and/or kinematical cuts which would make them not directly comparable to other data at different energies. Also, in the case of exclusive reactions, we have left out data where not all of the particles in the final state were unambiguously identified. This work contains reactions induced by neutrinos, gammas, charged pions, kaons, nucleons, antinucleons and hyperons. (orig./HSI)

  12. Systematic Analysis of the Non-Extensive Statistical Approach in High Energy Particle Collisions—Experiment vs. Theory †

    Directory of Open Access Journals (Sweden)

    Gábor Bíró

    2017-02-01

    Full Text Available The analysis of high-energy particle collisions is an excellent testbed for the non-extensive statistical approach. In these reactions we are far from the thermodynamical limit. In small colliding systems, such as electron-positron or nuclear collisions, the number of particles is several orders of magnitude smaller than the Avogadro number; therefore, finite-size and fluctuation effects strongly influence the final-state one-particle energy distributions. Due to the simple characterization, the description of the identified hadron spectra with the Boltzmann–Gibbs thermodynamical approach is insufficient. These spectra can be described very well with Tsallis–Pareto distributions instead, derived from non-extensive thermodynamics. Using the q-entropy formula, we interpret the microscopic physics in terms of the Tsallis q and T parameters. In this paper we give a view on these parameters, analyzing identified hadron spectra from recent years in a wide center-of-mass energy range. We demonstrate that the fitted Tsallis-parameters show dependency on the center-of-mass energy and particle species (mass. Our findings are described well by a QCD (Quantum Chromodynamics inspired parton evolution ansatz. Based on this comprehensive study, apart from the evolution, both mesonic and baryonic components found to be non-extensive ( q > 1 , besides the mass ordered hierarchy observed in the parameter T. We also study and compare in details the theory-obtained parameters for the case of PYTHIA8 Monte Carlo Generator, perturbative QCD and quark coalescence models.

  13. High energy hadron scattering

    International Nuclear Information System (INIS)

    Johnson, R.C.

    1980-01-01

    High energy and small momentum transfer 2 'yields' 2 hadronic scattering processes are described in the physical framework of particle exchange. Particle production in high energy collisions is considered with emphasis on the features of inclusive reactions though with some remarks on exclusive processes. (U.K.)

  14. Channelling and electromagnetic radiation of channelling particles

    International Nuclear Information System (INIS)

    Kalashnikov, N.

    1983-01-01

    A brief description is presented of the channelling of charged particles between atoms in the crystal lattice. The specificities are discussed of the transverse motion of channelling particles as are the origin and properties of quasi-characteristic radiation of channelling particles which accompany transfers from one band of permissible energies of the transverse motion of channelling particles to the other. (B.S.)

  15. Research activities on dosimetry for high energy neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Yasuhiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    The external dosimetry research group of JAERI has been calculating dose conversion coefficients for high-energy radiations using particle transport simulation codes. The group has also been developing radiation dose measurement techniques for high-energy neutrons in collaboration with some university groups. (author)

  16. Neutral strange particle production in high energy charged current neutrino deuterium interactions

    International Nuclear Information System (INIS)

    Son, D.

    1982-01-01

    In an exposure of the Fermilab 15-foot deuterium filled bubble chamber to a single horn focused wide band neutrino beam with energies between 10 and 250 GeV, 311 K/sub s/, 219 lambda and 7 Anti lambda are observed. These correspond to K 0 anti(K 0 ), lambda(Σ 0 ) and anti lambda production rates per charged current interaction of 0.170 +/- 0.010, 0.060 +/- 0.004, and 0.002 +/- 0.001, respectively, in 18.9 +/- 0.09% V 0 events of total charged current events. The inclusive lambda rate in nun interactions is significantly higher than that in nup interactions. The multiplicity of K 0 increases (or decreases) with increasing E/sub nu/, W, and Q 2 (or x/sub BETA), while that of lambda shows no significant variations. From a detailed study of lambda, lambda K 0 ], lambda K/sup */ +0 systems, the production rate of lambda from the charm quark decay is found to be (2.1 +/- 1.0)% of the total charged current, which leads to a small cross section for charmed baryon quasielastic production -40 cm 2 (90% CL) and a small semileptonic branching ratio of lambda/sub c/ + decay, B(lambda/sub c/ + → e + lambda x + , K 0 p, lambda π + π + π - , and antiK 0 pπ + π - decay modes of lambda/sub c/ + are studied and found consistent with our previous results. The gross probability that an (ss) pair is produced in lambda S = 0 neutrino reactions is estimated to be 0.19 +/- 0.06, which agrees well with that in hadronic experiments. The inclusive x/sub F/ and p/sub T 2 / distributions and their average values are very similar to those in hadronic experiments, which suggest that the majority of neutral strange particles are produced in neutrino reactions via the associated production mechanism

  17. Aerosol Sampling System for Collection of Capstone Depleted Uranium Particles in a High-Energy Environment

    International Nuclear Information System (INIS)

    Holmes, Thomas D.; Guilmette, Raymond A.; Cheng, Yung-Sung; Parkhurst, MaryAnn; Hoover, Mark D.

    2009-01-01

    The Capstone Depleted Uranium Aerosol Study was undertaken to obtain aerosol samples resulting from a kinetic-energy cartridge with a large-caliber depleted uranium (DU) penetrator striking an Abrams or Bradley test vehicle. The sampling strategy was designed to (1) optimize the performance of the samplers and maintain their integrity in the extreme environment created during perforation of an armored vehicle by a DU penetrator, (2) collect aerosols as a function of time post-impact, and (3) obtain size-classified samples for analysis of chemical composition, particle morphology, and solubility in lung fluid. This paper describes the experimental setup and sampling methodologies used to achieve these objectives. Custom-designed arrays of sampling heads were secured to the inside of the target in locations approximating the breathing zones of the vehicle commander, loader, gunner, and driver. Each array was designed to support nine filter cassettes and nine cascade impactors mounted with quick-disconnect fittings. Shielding and sampler placement strategies were used to minimize sampler loss caused by the penetrator impact and the resulting fragments of eroded penetrator and perforated armor. A cyclone train was used to collect larger quantities of DU aerosol for chemical composition and solubility. A moving filter sample was used to obtain semicontinuous samples for depleted uranium concentration determination. Control for the air samplers was provided by five remotely located valve control and pressure monitoring units located inside and around the test vehicle. These units were connected to a computer interface chassis and controlled using a customized LabVIEW engineering computer control program. The aerosol sampling arrays and control systems for the Capstone study provided the needed aerosol samples for physicochemical analysis, and the resultant data were used for risk assessment of exposure to DU aerosol

  18. Radiation protection for particle accelerators

    International Nuclear Information System (INIS)

    Verdu, G.; Rodenas, J.; Campayo, J.M.

    1992-01-01

    It a a great number of medical installations in spain using particle accelerators for radiotherapy. It is obvious the importance of an accurate estimation of the doses produced in these installations that may be received by health workers, patients or public. The lower values of dose limits established in the new ICRP recommendations imply a recalculation of items concerning such installations. In our country, specific guidelines for radiation protection in particle accelerators facilities have not been yet developed, however two possible guides can be used, NCRP report number 51 and DIN Standard 6847. Both have been analyzed comparatively in the paper, and major remarks have been summarized. Interest has been focused on thickness estimation of shielding barriers in order to verify whether must be modified to comply with the new dose limits. Primary and secondary barriers for a Mevatron used in a Medical Center, have been calculated and the results have been compared with actual data obtained from the installation, to test the adequacy of shielding barriers and radioprotection policies. The results obtained are presented and analyzed in order to state the implications of the new ICRP recommendations. (author)

  19. High-energy electron irradiation of NdFeB permanent magnets: Dependence of radiation damage on the electron energy

    International Nuclear Information System (INIS)

    Bizen, Teruhiko; Asano, Yoshihiro; Marechal, Xavier-Marie; Seike, Takamitsu; Aoki, Tsuyoshi; Fukami, Kenji; Hosoda, Naoyasu; Yonehara, Hiroto; Takagi, Tetsuya; Hara, Toru; Tanaka, Takashi; Kitamura, Hideo

    2007-01-01

    High-energy electron-beam bombardment of Nd 2 Fe 14 B-type permanent magnets induces radiation damage characterized by a drop in the magnetic field. Experiments carried out at the SPring-8 booster synchrotron, with 4, 6, and 8 GeV electrons, show that the drop in magnetic field is energy dependent. Electromagnetic shower simulations suggest that most of the radiation damage happens in a small region around the irradiation axis, and that the contribution of neutrons with large scattering angles or with low energies to the magnetic field change is small

  20. High-energy electron irradiation of NdFeB permanent magnets: Dependence of radiation damage on the electron energy

    Energy Technology Data Exchange (ETDEWEB)

    Bizen, Teruhiko [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)]. E-mail: bizen@spring8.or.jp; Asano, Yoshihiro [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Marechal, Xavier-Marie [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Seike, Takamitsu [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Aoki, Tsuyoshi [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Fukami, Kenji [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Hosoda, Naoyasu [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Yonehara, Hiroto [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Takagi, Tetsuya [JASRI SPring-8, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Hara, Toru [RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Tanaka, Takashi [RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Kitamura, Hideo [RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)

    2007-05-11

    High-energy electron-beam bombardment of Nd{sub 2}Fe{sub 14}B-type permanent magnets induces radiation damage characterized by a drop in the magnetic field. Experiments carried out at the SPring-8 booster synchrotron, with 4, 6, and 8 GeV electrons, show that the drop in magnetic field is energy dependent. Electromagnetic shower simulations suggest that most of the radiation damage happens in a small region around the irradiation axis, and that the contribution of neutrons with large scattering angles or with low energies to the magnetic field change is small.

  1. The Joint NASA/Goddard-University of Maryland Research Program in Charged Particle and High Energy Photon Detector Technology

    Science.gov (United States)

    Ipavich, F. M.

    1990-01-01

    The Univ. of Maryland portion investigated the following areas. The Space Physics Group performed studies of data from the AMPTE/CCE spacecraft CHEM experiment and found that the ratio of solar wind to photospheric abundances decreased rather smoothly with the first ionization potential (FIP) of the ion with the low FIP ion being about a factor of two overabundant. Carbon and hydrogen fit this trend particularly well. Several occurrences were analyzed of field aligned beams observed when CCE was upstream of the Earth's bow shock. Also using CHEM data, ring current intensity and composition changes during the main and recovery phases of the great geomagnetic storm that occurred in February 1986 was examined in detail. Still using CHEM data, ring current characteristics were examined in a survey of 20 magnetic storms ranging in size from -50 nT to -312 nT. A study was done of energetic ion anisotropy characteristics in the Earth's magnetosheath region using data from the UMD/MPE experiment on ISEE-1. The properties were analyzed of approx. 30 to 130 keV/e protons and alpha particles upstream of six quasi-parallel interplanetary shocks that passed by the ISEE-3 spacecraft during 1978 to 1979. Work from NASA-Goddard include studies from the High Energy Cosmic Ray Group, Low Energy Cosmic Ray Group, Low Energy Gamma Ray Group, High Energy Astrophysics Theory Group, and the X ray Astronomy Group.

  2. Laser-Driven Very High Energy Electron/Photon Beam Radiation Therapy in Conjunction with a Robotic System

    Directory of Open Access Journals (Sweden)

    Kazuhisa Nakajima

    2014-12-01

    Full Text Available We present a new external-beam radiation therapy system using very-high-energy (VHE electron/photon beams generated by a centimeter-scale laser plasma accelerator built in a robotic system. Most types of external-beam radiation therapy are delivered using a machine called a medical linear accelerator driven by radio frequency (RF power amplifiers, producing electron beams with an energy range of 6–20 MeV, in conjunction with modern radiation therapy technologies for effective shaping of three-dimensional dose distributions and spatially accurate dose delivery with imaging verification. However, the limited penetration depth and low quality of the transverse penumbra at such electron beams delivered from the present RF linear accelerators prevent the implementation of advanced modalities in current cancer treatments. These drawbacks can be overcome if the electron energy is increased to above 50 MeV. To overcome the disadvantages of the present RF-based medical accelerators, harnessing recent advancement of laser-driven plasma accelerators capable of producing 1-GeV electron beams in a 1-cm gas cell, we propose a new embodiment of the external-beam radiation therapy robotic system delivering very high-energy electron/photon beams with an energy of 50–250 MeV; it is more compact, less expensive, and has a simpler operation and higher performance in comparison with the current radiation therapy system.

  3. Structural and morphological changes in pseudobarrier films of anodic aluminum oxide caused by irradiation with high-energy particles

    International Nuclear Information System (INIS)

    Chernykh, M.A.; Belov, V.T.

    1988-01-01

    We have studied the structural and morphological changes, occurring under the electron beam in pseudobarrier films of anodic aluminum oxide, prepared in seven different solutions and irradiated beforehand by protons of x-rays, with the aim of elucidating the structure of anodic aluminum oxides. An increased stability of the pseudobarrier films of anodic aluminum oxide has been observed towards the action of the electron beam of an UEMV-100K microscope at standard working regimes (75 keV) as a result of irradiation with protons or x-rays. A difference has been found to exist between structural and morphological changes of anodic aluminum oxide films, prepared in different solutions, when irradiated with high-energy particles. A structural and phase inhomogeneity of amorphous pseudobarrier films of anodic aluminum oxide has been detected and its influence on the character of solid-phase transformations under the maximum-intensity electron beam

  4. Investigation of rare particle production in high energy nuclear collisions. Progress report, December 15, 1997--December 14, 1998

    International Nuclear Information System (INIS)

    Crawford, H.J.; Engelage, J.

    1998-01-01

    The program is an investigation of the hadronization process through experimental measurement of rare particle production in high energy nuclear interactions. These interactions provide an environment similar in energy density to the conditions in the Big Bang. The authors are currently involved in two major experiments to study this environment, E896 at the AGS and STAR at RHIC. They have completed the first physics running of E896, a search for the H dibaryon and measurement of hyperon production in AuAu collisions, and are in the process of analyzing the data. They have prototyped the STAR trigger and are in the process of fabricating its components and installing them in the STAR detector

  5. Characterization and performance optimization of radiation monitoring sensors for high energy physics experiments at the CERN LHC and Super-LHC

    CERN Document Server

    Mekki, Julien

    2009-01-01

    In order to study the matter originating from the universe, a new particle accelerator named the Large Hadron Collider (LHC) has been built at CERN. The radiation environment generated by the hadrons collisions in the high energy physics experiments of the LHC will be complex and locally very intense. For monitoring this complex radiation field, dosimeters have been installed in the LHC experiments. In previous study, RadFET dosimeters and PIN diodes have been characterized for their use in the particle accelerator. However, even if the RadFETs sensors have been already extensively characterized, their radiation response can be affected by their package. Depending on the material and the geometry, the package can induce errors in the dose measurement. In this thesis, a complete study has been carried out in order to evaluate its influence. Concerning the PIN diodes, the readout protocol used for the LHC is no longer valuable for the Super-LHC. Therefore, a complete study on their radiation response has been p...

  6. Development of new radiation sources using high energy electrons and their applications

    International Nuclear Information System (INIS)

    Tomimasu, Takio

    1992-01-01

    Present and future of compact electron storage rings used for lithography, free electron laser (FEL) and angiography are reviewed and discussed. Recent development of the compact rings with insertion devices capable of storing 1-A beam enable these prospective applications and generations of strong backward compton scattered γ-rays and any kind of elliptically polarizing photons. The high-energy, high current and small-energy spread beam acceleration using conventional type electron linacs is also discussed for the generations of UV-FEL and slow positrons. (author)

  7. Radiation defects in InN irradiated with high-energy electrons

    International Nuclear Information System (INIS)

    Zhivul'ko, V.D.; Mudryj, A.V.; Yakushev, M.V.; Martin, R.; Shaff, V.; Lu, Kh.; Gurskij, A.L.

    2013-01-01

    The influence of high energy (6 MeV, fluencies 10 15 – 10 18 cm -2 ) electron irradiation on the fundamental absorption and luminescence properties of InN thin films which were grown on sapphire substrates by molecular bean epitaxial has been studied. It is found that electron irradiation increases the electron concentration and band gap energy E g of InN. The shift of the band gap energy E g is a manifestation of the Burshtein-Mossa effect. (authors)

  8. 175th International School of Physics "Enrico Fermi" : Radiation and Particle Detectors

    CERN Document Server

    Bottigli, U; Oliva, P

    2010-01-01

    High energy physics (HEP) has a crucial role in the context of fundamental physics. HEP experiments make use of a massive array of sophisticated detectors to analyze the particles produced in high-energy scattering events. This book contains the papers from the workshop 'Radiation and Particle Detectors', organized by the International School of Physics, and held in Varenna in July 2009. Its subject is the use of detectors for research in fundamental physics, astro-particle physics and applied physics. Subjects covered include the measurement of: the position and length of ionization trails, time of flight velocity, radius of curvature after bending the paths of charged particles with magnetic fields, coherent transition radiation, synchrotron radiation, electro-magnetic showers produced by calorimetric methods and nuclear cascades produced by hadrons in massive steel detectors using calorimetry. Detecting muons and the detection of Cherenkov radiation are also covered, as is the detection of neutrinos by ste...

  9. High-Energy Radiation from Thunderstorms with ADELE: TGFs, Steps, and Glows

    Science.gov (United States)

    Smith, David M.; Kelley, Nicole; Martinez-McKinney, Forest; Zhang, Zi Yan; Hazelton, Bryna; Grefenstette, Brian; Splitt, Michael; Lazarus, Steven; Ulrich, William; Levine, Steven; hide

    2011-01-01

    The biggest challenge in the study of high-energy processes in thunderstorms is getting a detector to the vicinity of the electrically active regions of a storm. The Airborne Detector for Energetic Lightning Emissions (ADELE) has been used to detect gamma rays from aircraft above storms and from a storm-chasing van on the ground. In August 2009, ADELE flew above Florida storms in a Gulfstream V jet, detecting the first terrestrial gamma-ray flash (TGF) seen from a plane and continuous glows of high-energy emission above thunderclouds. The presence of these glows suggests that a gradual process of relativistic runaway and feedback may help limit the total amount of charging in thunderstorms, in contrast to the traditional view that only lightning discharges compete with the charging process. The upper limits on TGF emission from intracloud and cloud-to-ground lightning from the ADELE flights demonstrated conclusively that a TGF of the sort seen from space is not associated with most lightning and not necessary to trigger it. In August 2010, observations from a van detected stepped-leader x-ray emission from at least four lightning strikes in ten days of operations. This mode of operation is therefore promising for future observations of the stepping process, although a more varied suite of instrumentation, in particular a flash-distance detector, would be useful. We will report on these results and on future possibilities for ADELE campaigns.

  10. Radiation spectra of high-energy electrons in monocrystals of various thickness and orientation

    International Nuclear Information System (INIS)

    Avakyan, R.O.; Agan'yants, A.O.; Akopov, N.Z.; Vartanov, Yu.A.; Vartapetyan, G.A.; Lebedev, A.N.; Mirzoyan, R.M.; Taroyan, S.P.; Danagulyan, S.S.

    1982-01-01

    Yield of photons with energies 20-200 MeV at motion of the 4.7 GeV electron beam in parallel to the axis of a diamond crystal exceeds substantially the corresponding yield from a disoriented target. A similarity is observed in the radiation spectra within the crystal thickness range of 100- 610 mkm. The radiation yield is suppressed at certain energies of the γ quanta [ru

  11. High-energy radiation and polymers: A review of commercial processes and emerging applications

    International Nuclear Information System (INIS)

    Clough, R.L.

    2001-01-01

    Ionizing radiation has been found to be widely applicable in modifying the structure and properties of polymers, and can be used to tailor the performance of either bulk materials or surfaces. Fifty years of research in polymer radiation chemistry has led to numerous applications of commercial and economic importance, and work remains active in the application of radiation to practical uses involving polymeric materials. This paper provides a survey of radiation-processing methods of industrial interest, ranging from technologies already commercially well established, through innovations in the active R and D stage which show exceptional promise for future commercial use. Radiation-processing technologies are discussed under the following categories: cross-linking of plastics and rubbers, curing of coatings and inks, heat-shrink products, fiber-matrix composites, chain-scission for processing control, surface modification, grafting, hydrogels, sterilization, natural product enhancement, plastics recycling, ceramic precursors, electronic property materials, ion-track membranes and lithography for microdevice production. In addition to new technological innovations utilizing conventional gamma and e-beam sources, a number of promising new applications make use of novel radiation types which include ion beams (heavy ions, light ions, highly focused microscopic beams and high-intensity pulses), soft X-rays which are focused, coherent X-rays (from a synchrotron) and e-beams which undergo scattering to generate patterns

  12. Comparison between the mechanical and radiative electron-capture processes at high energies

    International Nuclear Information System (INIS)

    Gonzalez, A.D.; Miraglia, J.E.

    1984-01-01

    The ground-state--ground-state mechanical and radiative electron-capture processes are studied at very high, but not relativistic, projectile velocities. Three-body calculations were carried out with use of the continuum distorted-wave theoretical method for both processes. Total cross sections and final-atom angular distributions were computed, and the importance of each mechanism examined. For total cross sections, the numerical results reaffirm that the radiative process is the predominant mechanism at very high projectile energies. For a given incident charge, the range of projectile energies in which the nonrelativistic radiative mechanism is the most important decreases as the target charge increases. It is found that the radiative mechanism produces a very sharp final-atom angular distribution in the forward direction. When both processes, the radiative and mechanical, give the same total cross section, the calculations show that the radiative differential cross section in the forward direction is almost 2 orders of magnitude larger than the mechanical one

  13. High energy x-ray synchrotron radiation analysis of residual stress distribution of shot-peened steels

    International Nuclear Information System (INIS)

    Tanaka, Keisuke; Akiniwa, Yoshiaki; Kimachi, Hirohisa; Suzuki, Kenji; Yanase, Etsuya; Nishio, Kouji; Kusumi, Yukihiro

    2001-01-01

    A high energy X-ray beam from synchrotron radiation source SPring-8 was used to determine the residual stress distribution beneath the shot-peened surface of carbon steel plates. By using the monochromatic X-ray beam with an energy of 72 keV, the relation between 2θ and sin 2 ψ was obtained by the side-inclination method upto sin 2 ψ = 0.9. The distribution of the residual stress was determined from the non-linearity of the relation between 2θ and sin 2 ψ. (author)

  14. [Effects of ionizing radiation on scintillators and other particle detectors

    International Nuclear Information System (INIS)

    Proudfoot, J.

    1992-01-01

    It is my task to summarise the great variety of topics (covering a refreshing mix of physics, chemistry and technology) presented at this conference, which has focused on the effects of ionising radiation on scintillators and other particle detectors. One of the reasons and the central interest of many of the participants was the use of such detectors in experiments at two future large hadron colliders: the Superconducting Super Collider to be operating outside of Dallas in the United States by the turn of the decade and its European counterpart the Large Hadron Collider to be operating outside of Geneva in Switzerland on a similar time scale. These accelerators are the ''apple of the high energy physicist's eye.'' Their goal is to uncover the elusive Higgs particle and thereby set the cornerstone in our current knowledge of elementary particle interactions. This is the Quest, and from this lofty height the presentations rapidly moved on to the specific questions of experimental science: how such an experiment is carried out; why radiation damage is an issue; how radiation damage affects detectors; which factors affect radiation damage characteristics; which factors are not affected by radiation damage; and how better detectors may be constructed. These were the substance of this conference

  15. Chemical modification of fibers and fabrics with high-energy radiation

    International Nuclear Information System (INIS)

    Stannett, V.; Walsh, W.K.; Bittencourt, E.; Liepins, R.; Surles, J.R.

    1977-01-01

    Some fundamental considerations related to the radiation modification of fibers and fabrics are discussed. Experiments are described on the radiation ''grafting'' of various phosphorus- and bromine-containing vinyl monomers to polyester, cotton, and their blends to impart flame resistance. It was found that the flame retardancy was more efficient when the grafted polymer was located inside the fiber. The efficiency of the bromine containing polymers was found to be related to the bromine/aliphatic hydrogen ratio and to the thermal stability of the polymers. Experiments are also described illustrating the successful use of radiation processing with a number of vinyl monomers and oligomers to impart water sorbancy, for the bonding of nonwoven fabrics for fabric coating, and for the binding of pigment prints. 11 tables, 18 figures

  16. High-energy cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Gaisser, Thomas K. [Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)]. E-mail: gaisser@bartol.udel.edu; Stanev, Todor [Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)

    2006-10-17

    After a brief review of galactic cosmic rays in the GeV to TeV energy range, we describe some current problems of interest for particles of very high energy. Particularly interesting are two features of the spectrum, the knee above 10{sup 15} eV and the ankle above 10{sup 18} eV. An important question is whether the highest-energy particles are of extra-galactic origin and, if so, at what energy the transition occurs. A theme common to all energy ranges is use of nuclear abundances as a tool for understanding the origin of the cosmic radiation.

  17. Ultra high energy cosmic rays

    International Nuclear Information System (INIS)

    Watson, A.A.

    1986-01-01

    Cosmic radiation was discovered 70 years ago but its origin remains an open question. The background to this problem is outlined and attempts to discover the origin of the most energetic and rarest group above 10 15 eV are described. Measurements of the energy spectrum and arrival direction pattern of the very highest energy particles, mean energy about 6 x 10 19 eV, are used to argue that these particles originate outside our galaxy. Recent evidence from the new field of ultra high energy γ-ray astronomy are discussed in the context of a galactic origin hypothesis for lower energy cosmic rays. (author)

  18. Theoretical high energy physics

    International Nuclear Information System (INIS)

    Lee, T.D.

    1993-01-01

    Brief reports are given on the work of several professors. The following areas are included: quantum chromodynamics calculations using numerical lattice gauge theory and a high-speed parallel computer; the ''spin wave'' description of bosonic particles moving on a lattice with same-site exclusion; a high-temperature expansion to 13th order for the O(4)-symmetric φ 4 model on a four-dimensional F 4 lattice; spin waves and lattice bosons; superconductivity of C 60 ; meson-meson interferometry in heavy-ion collisions; baryon number violation in the Standard Model in high-energy collisions; hard thermal loops in QCD; electromagnetic interactions of anyons; the relation between Bose-Einstein and BCS condensations; Euclidean wormholes with topology S 1 x S 2 x R; vacuum decay and symmetry breaking by radiative corrections; inflationary solutions to the cosmological horizon and flatness problems; and magnetically charged black holes

  19. Problems in the development of high-energy radiation processing of woven and knitted fabrics

    International Nuclear Information System (INIS)

    Ihme, B.; Maeder, E.; Mally, S.

    1983-01-01

    The modification of hygienic properties of garments made of polyamide and polyester planar structures has been investigated. The results underline the fact that radiation-induced modification aimed at increasing the serviceability of textile planar structures is a relatively complicated process of textile finishing resulting in the need of additional chemicals, facilities, manpower, and energy. (author)

  20. Design and test results of a low-noise readout integrated circuit for high-energy particle detectors

    International Nuclear Information System (INIS)

    Zhang Mingming; Chen Zhongjian; Zhang Yacong; Lu Wengao; Ji Lijiu

    2010-01-01

    A low-noise readout integrated circuit for high-energy particle detector is presented. The noise of charge sensitive amplifier was suppressed by using single-side amplifier and resistors as source degeneration. Continuous-time semi-Gaussian filter is chosen to avoid switch noise. The peaking time of pulse shaper and the gain can be programmed to satisfy multi-application. The readout integrated circuit has been designed and fabricated using a 0.35 μm double-poly triple-metal CMOS technology. Test results show the functions of the readout integrated circuit are correct. The equivalent noise charge with no detector connected is 500-700 e in the typical mode, the gain is tunable within 13-130 mV/fC and the peaking time varies from 0.7 to 1.6 μs, in which the average gain is about 20.5 mV/fC, and the linearity reaches 99.2%. (authors)

  1. Structure of small-scale standing azimuthal Alfven waves interacting with high-energy particles in the magnetosphere

    International Nuclear Information System (INIS)

    Klimushkin, D.Yu.

    1998-01-01

    The effect of bounce-drift instability on the structure of small-scale azimuthal Alfven waves in the magnetosphere is studied with allowance for the curvature of the geomagnetic field lines. The pressure of the background plasma is assumed to be zero. As early as 1993, Leonovich and Mazur showed that Alfven waves with m>>1, being standing waves along magnetic field lines, propagate, at the same time, across the magnetic surfaces. As these waves propagate through the magnetosphere, they interact with a group of high-energy particles and, thereby, are amplified with a growth rate dependent on the radial coordinate, i.e., a coordinate perpendicular to the magnetic sheaths. Near the Alfven resonance surface, the growth rate approaches zero, and the waves are damped completely due to the energy dissipation in the ionosphere. As the growth rate increases, the maximum of the wave amplitude is displaced to the Alfven resonance region and the most amplified waves are those whose magnetic field vectors oscillate in the azimuthal direction. Among the waves excited in a plasma resonator that is formed near the plasmapause, the most amplified are those with radial polarization

  2. High energy astrophysics

    International Nuclear Information System (INIS)

    Engel, A.R.

    1979-01-01

    High energy astrophysical research carried out at the Blackett Laboratory, Imperial College, London is reviewed. Work considered includes cosmic ray particle detection, x-ray astronomy, gamma-ray astronomy, gamma and x-ray bursts. (U.K.)

  3. The role of high-energy synchrotron radiation in biomedical trace element research

    International Nuclear Information System (INIS)

    Pounds, J.G.; Long, G.J.; Kwiatek, W.M.; Jones, K.W.; Gordon, B.M.; Hanson, A.L.

    1987-01-01

    This paper will present the results of an investigation of the distribution of essential elements in the normal hepatic lobule. the liver is the organ responsible for metabolism and storage of most trace elements. Although parenchymal hepatocytes are rather uniform histologically, morphometry, histochemistry, immunohistochemistry, and microdissection with microchemical investigations have revealed marked heterogeneity on a functional and biochemical level. Hepatocytes from the periportal and perivenous zones of the liver parrenchyma differ in oxidative energy metabolism, glucose uptake and output, unreagenesis, biotransformation, bile acid secretion, and palsma protein synthesis and secretion. Although trace elements are intimately involved in the regulation and maintenance of these functions, little is known regarding the heterogeneity of trace element localization of the liver parenchyma. Histochemical techniques for trace elements generally give high spatial resolution, but lack specificity and stoichiometry. Microdissection has been of marginal usefulness for trace element analyses due to the very small size of the dissected parenchyma. The characteristics of the high-energy x-ray microscope provide an effective approach for elucidating the trace element content of these small biological structures or regions. 5 refs., 1 fig., 1 tab

  4. Effect of High Energy Radiation on Mechanical Properties of Graphite Fiber Reinforced Composites. M.S. Thesis

    Science.gov (United States)

    Naranong, N.

    1980-01-01

    The flexural strength and average modulus of graphite fiber reinforced composites were tested before and after exposure to 0.5 Mev electron radiation and 1.33 Mev gamma radiation by using a three point bending test (ASTM D-790). The irradiation was conducted on vacuum treated samples. Graphite fiber/epoxy (T300/5208), graphite fiber/polyimide (C6000/PMR 15) and graphite fiber/polysulfone (C6000/P1700) composites after being irradiated with 0.5 Mev electron radiation in vacuum up to 5000 Mrad, show increases in stress and modulus of approximately 12% compared with the controls. Graphite fiber/epoxy (T300/5208 and AS/3501-6), after being irradiated with 1.33 Mev gamma radiation up to 360 Mrads, show increases in stress and modulus of approximately 6% at 167 Mrad compared with the controls. Results suggest that the graphite fiber composites studied should withstand the high energy radiation in a space environment for a considerable time, e.g., over 30 years.

  5. Response study of fission track detectors using two different moderator designs in a high-energy radiation field

    International Nuclear Information System (INIS)

    Mayer, S.; Boschung, M.; Fiechtner, A.; Fuerstner, M.; Wernli, C.

    2008-01-01

    Fission track detectors in the center of moderating spheres are routinely used to measure the ambient dose equivalent due to neutrons in the environmental dosimetry at Paul Scherrer Institut (PSI). Originally, the system was designed to cope with neutrons from skyshine effects. Later, the system was also adapted behind the shielding of PSI's accelerators. Nowadays, as a consequence of continuously upgrading accelerator energies and intensities, the neutron energy behind thick shielding can range from fractions of eV to about 1 GeV (e.g. at CERN). For this reason a measurement campaign in a high-energy stray radiation field at CERN's High-Energy Reference Field Facility (CERF) was initiated to study and compare the response of the already existing detector-moderator configuration and a new design, the 'GSI ball'. Employing an additional lead layer in a moderator sphere of 32.5 cm diameter, the GSI ball was primarily designed for the use with thermoluminescent based dosimeters in its center in order to optimize the response for the measurement of H*(10) to higher neutron energies. In this work, the measurement results for fission track detectors using two different radiator materials in the PSI and the GSI moderator are presented. Based on these studies, on the one hand, field calibration factors for the use in presumably similar high-energy fields around accelerators could be deduced. On the other hand, it could be shown that there is no need to replace the established PSI moderator by the GSI moderator since the combination of fission track detector and GSI moderator does not result in a significant sensitivity improvement

  6. Response study of fission track detectors using two different moderator designs in a high-energy radiation field

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, S. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)], E-mail: Sabine.Mayer@psi.ch; Boschung, M.; Fiechtner, A. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Fuerstner, M. [CERN, CH-1211 Geneva 23 (Switzerland); Wernli, C. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

    2008-02-15

    Fission track detectors in the center of moderating spheres are routinely used to measure the ambient dose equivalent due to neutrons in the environmental dosimetry at Paul Scherrer Institut (PSI). Originally, the system was designed to cope with neutrons from skyshine effects. Later, the system was also adapted behind the shielding of PSI's accelerators. Nowadays, as a consequence of continuously upgrading accelerator energies and intensities, the neutron energy behind thick shielding can range from fractions of eV to about 1 GeV (e.g. at CERN). For this reason a measurement campaign in a high-energy stray radiation field at CERN's High-Energy Reference Field Facility (CERF) was initiated to study and compare the response of the already existing detector-moderator configuration and a new design, the 'GSI ball'. Employing an additional lead layer in a moderator sphere of 32.5 cm diameter, the GSI ball was primarily designed for the use with thermoluminescent based dosimeters in its center in order to optimize the response for the measurement of H*(10) to higher neutron energies. In this work, the measurement results for fission track detectors using two different radiator materials in the PSI and the GSI moderator are presented. Based on these studies, on the one hand, field calibration factors for the use in presumably similar high-energy fields around accelerators could be deduced. On the other hand, it could be shown that there is no need to replace the established PSI moderator by the GSI moderator since the combination of fission track detector and GSI moderator does not result in a significant sensitivity improvement.

  7. The response of different types of TL lithium fluoride detectors to high-energy mixed radiation fields

    Energy Technology Data Exchange (ETDEWEB)

    Obryk, B. [Institute of Nuclear Physics PAN (IFJ), ul. Radzikowskiego 152, 31-342 Krakow (Poland)], E-mail: barbara.obryk@ifj.edu.pl; Bilski, P.; Budzanowski, M. [Institute of Nuclear Physics PAN (IFJ), ul. Radzikowskiego 152, 31-342 Krakow (Poland); Fuerstner, M. [CERN - European Organization for Nuclear Research, 1211 Geneva 23 (Switzerland); Ilgner, C. [CERN - European Organization for Nuclear Research, 1211 Geneva 23 (Switzerland) and University of Dortmund, Dortmund (Germany); Jaquenod, F. [Ecole d' Ingenieurs de Geneve, Geneva (Switzerland); Olko, P.; Puchalska, M. [Institute of Nuclear Physics PAN (IFJ), ul. Radzikowskiego 152, 31-342 Krakow (Poland); Vincke, H. [CERN - European Organization for Nuclear Research, 1211 Geneva 23 (Switzerland)

    2008-02-15

    Thermoluminescent (TL) dosimeters are routinely used to monitor absorbed doses in many kinds of radiation fields which contain photons, electrons and neutrons. However, TLDs are mainly calibrated to photon sources. We studied the response of TLDs to complex secondary fields arising during the operation of high-energy accelerators (e.g. the Large Hadron Collider (LHC) at CERN). The experiments were conducted at the CERN-EU high-energy reference field facility (CERF). Six different LiF-based TLDs (MTS-N, MTS-7, MTS-6, MCP-N, MCP-7, MCP-6) were exposed to various secondary CERF's fields (both for high and low doses), by placing them at various positions: at the target and concrete top and side positions. For the experiment at the target the corresponding Monte Carlo calculations were also carried out using the FLUKA transport code and compared with experimental results. In addition, alanine dosimeters were used as an independent reference. The results show that TLDs are well suited for monitoring radiation fields around the LHC. Nevertheless, further investigations are required, some of which are in progress.

  8. Measurements of internal stresses in bond coating using high energy x-rays from synchrotron radiation source

    CERN Document Server

    Suzuki, K; Akiniwa, Y; Nishio, K; Kawamura, M; Okado, H

    2002-01-01

    Thermal barrier coating (TBC) techniques enable high temperature combustion of turbines made of Ni-base alloy. TBC is made of zirconia top coating on NiCoCrAlY bond coating. The internal stresses in the bond coating play essential role in the delamination or fracture of TBC in service. With the X-rays from laboratory equipments, it is impossible to measure nondestructively the internal stress in the bond coating under the top coating. synchrotron radiations with a high energy and high brightness have a large penetration depth as compared with laboratory X-rays. Using the high energy X-rays from the synchrotron radiation, it is possible to measure the internal stress in the bond coating through the top coating. In this study, the furnace, which can heat a specimen to 1473 K, was developed for the stress measurement of the thermal barrier coatings. The internal stresses in the bond coating were measured at the room temperature, 773 K, 1073 K and 1373 K by using the 311 diffraction from Ni sub 3 Al with about 73...

  9. Size measurement of radioactive aerosol particles in intense radiation fields using wire screens and imaging plates

    Energy Technology Data Exchange (ETDEWEB)

    Oki, Yuichi; Tanaka, Toru; Takamiya, Koichi; Ishi, Yoshihiro; UesugI, Tomonori; Kuriyama, Yasutoshi; Sakamoto, Masaaki; Ohtsuki, Tsutomu [Kyoto University Research Reactor Institute, Osaka (Japan); Nitta, Shinnosuke [Graduate School of Engineering, Kyoto University, Kyoto (Japan); Osada, Naoyuki [Advanced Science Research Center, Okayama University, Okayama (Japan)

    2016-09-15

    Very fine radiation-induced aerosol particles are produced in intense radiation fields, such as high-intensity accelerator rooms and containment vessels such as those in the Fukushima Daiichi nuclear power plant (FDNPP). Size measurement of the aerosol particles is very important for understanding the behavior of radioactive aerosols released in the FDNPP accident and radiation safety in high-energy accelerators. A combined technique using wire screens and imaging plates was developed for size measurement of fine radioactive aerosol particles smaller than 100 nm in diameter. This technique was applied to the radiation field of a proton accelerator room, in which radioactive atoms produced in air during machine operation are incorporated into radiation-induced aerosol particles. The size of 11C-bearing aerosol particles was analyzed using the wire screen technique in distinction from other positron emitters in combination with a radioactive decay analysis. The size distribution for 11C-bearing aerosol particles was found to be ca. 70 μm in geometric mean diameter. The size was similar to that for 7Be-bearing particles obtained by a Ge detector measurement, and was slightly larger than the number-based size distribution measured with a scanning mobility particle sizer. The particle size measuring method using wire screens and imaging plates was successfully applied to the fine aerosol particles produced in an intense radiation field of a proton accelerator. This technique is applicable to size measurement of radioactive aerosol particles produced in the intense radiation fields of radiation facilities.

  10. Spin rotation and depolarization of high-energy particles in crystals at Hadron Collider (LHC) and Future Circular Collider (FCC) energies and the possibility to measure the anomalous magnetic moments of short-lived particles

    CERN Document Server

    Baryshevsky, V.G.

    2015-01-01

    We study the phenomena of spin rotation and depolarization of high-energy particles in crystals in the range of high energies that will be available at Hadron Collider (LHC) and Future Circular Collider (FCC). It is shown that these phenomena can be used to measure the anomalous magnetic moments of short-lived particles in this range of energies. We also demonstrate that the phenomenon of particle spin depolarization in crystals provides a unique possibility of measuring the anomalous magnetic moment of negatively-charged particles (e.g., beauty baryons), for which the channeling effect is hampered due to far more rapid dechanneling as compared to that for positively-charged particles. Channeling of particles in either straight or bent crystals with polarized nuclei could be used for polarization and the analysis thereof of high-energy particles.

  11. Preparation of plastic-cellulose compounds by high energy gamma radiation

    International Nuclear Information System (INIS)

    Rosa, M.C.F.

    1978-01-01

    The use of high intensity sources of ionizing radiation for inducing polymer cross-linking was studied and the feasibility of its application in making plastic and cellulose combined compounds, particularly plates formed by paper sheets aglutinated with polyester resin, was analyzed. Several types of paper capable of being used in the plate composition were tested. It was verified that with the preparation technique used in this work the ordinary filter paper gave the best results. By different material testing techniques it was found that the chemical and mechanical properties of plates cured with radiation doses of about 1.5 Mrad are favorably compared with those exhibited by plates of equal composition, cured by the classic method (adding chemical initiator and accelerator) [pt

  12. A method to detect ultra high energy electrons using earth's magnetic field as a radiator

    Science.gov (United States)

    Stephens, S. A.; Balasubrahmanyan, V. K.

    1983-01-01

    It is pointed out that the detection of electrons with energies exceeding a few TeV, which lose energy rapidly through synchrotron and inverse Compton processes, would provide valuable information on the distribution of sources and on the propagation of cosmic rays in the solar neighborhood. However, it would not be possible to measure the energy spectrum beyond a few TeV with any of the existing experimental techniques. The present investigation is, therefore concerned with the possibility of detecting electrons with energies exceeding a few TeV on the basis of the photons emitted through synchrotron radiation in the earth's magnetic field. Attention is given to the synchrotron radiation of electrons in the earth's magnetic field, detector response and energy estimation, and the characteristics of an ideal detector, capable of detecting photons with energies equal to or greater than 20 keV.

  13. Performance of the ATLAS Transition Radiation Tracker with Comic Rays and First High Energy Collisions at LHC

    CERN Document Server

    Degenhardt, J D; The ATLAS collaboration

    2010-01-01

    The ATLAS Transition Radiation Tracker (TRT) is the outermost of the three sub-systems of the ATLAS Inner Detector at the Large Hadron Collider (LHC) at CERN. It consists of close to 300000 thin-wall drift tubes (straws) providing on average 30 two-dimensional space points with 130 μm resolution for charged particle tracks with |η| < 2 and pT > 0.5 GeV. Along with continuous tracking, it provides particle identification capability through the detection of transition radiation X-ray photons generated by high velocity particles in the many polymer fibers or films that fill the spaces between the straws. The custom-made radiation-hard front-end electronics implements two thresholds to discriminate the signals: a low threshold (< 300 eV) for registering the passage of minimum ionizing particles, and a high threshold (> 6 keV) to flag the absorption of transition radiation X-rays. The TRT was successfully commissioned with data collected from several million cosmic ray muons. A specia...

  14. Degradation Mechanism of Poly(Ether-Urethane) Estane Induced by High Energy Radiation (III) : Radiolytic Gases and Water Soluble Products

    International Nuclear Information System (INIS)

    Dannoux, A.

    2006-01-01

    Within the framework of nuclear waste management, there is interest in the prediction of long-term behaviour of organic materials subjected to high energy radiation. Once organic waste has been stored, gases and low molecular products might be generated from materials irradiated by radionuclides. Long-term behaviour of organic material in nuclear waste has several common concerns with radiation ageing of polymers. But a more detailed description of the chemical evolution is needed for nuclear waste management. In a first approach, an extensive work on radiation ageing is used to identify the different processes encountered during the degradation of a polyurethane, including oxidation dose rate-effects and influence of dose on the oxidation mechanism. In a second approach, a study is performed to identify and quantify gases and possible production of water soluble chemical complexing agents which might enhance radionuclides migration away from the repository. In this work, we present results concerning the production of radiolytic gases and the formation of water soluble oligomers reached with leaching tests Films were made from a poly(ether-urethane) synthesized from methylene bis(p-phenyl isocyanate) (MDI) and poly(tetramethylene glycol) (PTMG) with 1,4 butanediol (BD) and were irradiated by high-energy electron beam to cover a wide doses range and by γ rays to determine the formation/consumption yields of gases. They were measured by mass spectrometry and gas-chromatography/mass spectrometry (GC/MS). The migration of water soluble oligomers in water was reached by measuring the weight loss versus leaching time. The identification of oligomers was performed by using a mass spectrometry with an electrospray ionisation interface (ESI-MS-MS). The analysis of radiolytic gases indicates the formation of H 2 , CO 2 and CO with respective radiolytic yields of 1, 0.5 and 0.3 molecule/100 eV. The consumption of O 2 is evaluated to 6 molecules/100 eV. For absorbed doses

  15. HIGH-ENERGY EMISSION OF GRB 130427A: EVIDENCE FOR INVERSE COMPTON RADIATION

    International Nuclear Information System (INIS)

    Fan, Yi-Zhong; Zhang, Fu-Wen; He, Hao-Ning; Zhou, Bei; Yang, Rui-Zhi; Jin, Zhi-Ping; Wei, Da-Ming; Tam, P. H. T.; Liang, Yun-Feng

    2013-01-01

    A nearby superluminous burst GRB 130427A was simultaneously detected by six γ-ray space telescopes (Swift, the Fermi GLAST Burst Monitor (GBM)/Large Area Telescope, Konus-Wind, SPI-ACS/INTEGRAL, AGILE, and RHESSI) and by three RAPTOR full-sky persistent monitors. The isotropic γ-ray energy release is ∼10 54 erg, rendering it the most powerful explosion among gamma-ray bursts (GRBs) with a redshift z ≤ 0.5. The emission above 100 MeV lasted about one day, and four photons are at energies greater than 40 GeV. We show that the count rate of 100 MeV-100 GeV emission may be mainly accounted for by the forward shock synchrotron radiation and the inverse Compton radiation likely dominates at GeV-TeV energies. In particular, an inverse Compton radiation origin is favored for the ∼(95.3, 47.3, 41.4, 38.5, 32) GeV photons arriving at t ∼ (243, 256.3, 610.6, 3409.8, 34366.2) s after the trigger of Fermi-GBM. Interestingly, the external inverse Compton scattering of the prompt emission (the second episode, i.e., t ∼ 120-260 s) by the forward-shock-accelerated electrons is expected to produce a few γ-rays at energies above 10 GeV, while five were detected in the same time interval. A possible unified model for the prompt soft γ-ray, optical, and GeV emission of GRB 130427A, GRB 080319B, and GRB 090902B is outlined. Implications of the null detection of >1 TeV neutrinos from GRB 130427A by IceCube are discussed

  16. Some aspects of radiation protection near high-energy proton accelerators

    CERN Document Server

    Tuyn, Jan Willem Nicolaas

    1977-01-01

    The CERN site near Geneva borders Satigny and Meyrin in Switzerland and Saint-Genis-Pouilly and Prevention in France. The 600 MeV proton synchrocyclotron (SC) has been in operation since 1957, the 28 GeV proton synchrotron (PS) since 1960, and the Intersecting Storage Rings (ISR) since 1971. A fourth large accelerator, the 400 GeV super proton synchrotron (SPS), will soon be in service. The internal and external radiation protection problems caused by these machines, together with the solutions, are reviewed in the light of experience. (5 refs).

  17. Cadmium telluride gamma-radiation detectors with a high energy resolution

    International Nuclear Information System (INIS)

    Alekseeva, L.A.; Dorogov, P.G.; Ivanov, V.I.; Khusainov, A.K.

    1985-01-01

    This paper considers the possibility of improving the energy resolution of cadmium telluride gamma-radiation detectors through the choice of the geometry and size of the sensitive region of the detector. The optimum ratio of the product of the mobility and lifetime for electrons to the same product for holes from the point of view of energy resolution is greater than or equal to 10 2 for a detector of spherical geometry and should be less than or equal to 10 for a cylindrical geometry and approximately 1 for a planar geometry. The optimum values of the major and minor radii of a spherical detector are calculated

  18. Surface dose measurements under stretched, perforated thermoplast sheets and under protective wound dressings for high energy photon radiation

    International Nuclear Information System (INIS)

    Staudenraus, J.; Christ, G.

    2000-01-01

    Patient fixation masks made of perforated thermoplast sheets are widely used in radiotherapy. These masks in particular serve to immobilize the head and neck region during radiation treatment. We placed samples made of differently stretched, perforated mask material on the surface of a white polystyrene (RW3) phantom and measured for high energy photon beams from Co-60 radiation up to 25 MV bremsstrahlung the dose increase resulting from the build-up under the hole and bridge areas. Depending on the energy of the incident beam and the thickness of the stretched mask material we observed a dose increase under the bridges at the phantom surface of 55% up to 140% compared to the dose without a layer of mask material. Under a hole the dose increase is almost half the value found under a bridge. However, deeper than 1 mm under the phantom surface this difference in dose increase under holes and bridges decreases to less than 10%. The mean dose increase under a perforated thermoplast sheet is lower than the dose increase under a homogeneous sheet made of the same material with the same mean thickness. Radiation induced skin lesions or an ulcerating tumour, respectively, may require a protective wound dressing under a patient fixation mask during radiation therapy. Choosing a thin hydrocolloid wound dressing the additional dose increase of the skin, compared to the dose increase due to the fixation mask, can be kept low. (orig.) [de

  19. High-energy X-ray detection using organic luminescent materials: a novel application for radiation therapy

    International Nuclear Information System (INIS)

    Schimitberger, Thiago; Ferreira, Giovana Ribeiro; Silva, Mariana de Melo; Saraiva, M.F.; Bianchi, Rodrigo Fernando

    2010-01-01

    In this work, it is presented the characterization and fabrication of a novel ionizing radiation sensor for high energy X-ray (6 MeV). It is used organic luminescent materials usually applied in light-emitting and nanostructure device, but still few explored in radiation dosimetry. Organic solutions of tris(8-hydroxyquinolinato) aluminum - Alq_3 and poly[2-methoxy-5-(2'-ethylhexyloxy)-p-phenylene vinylene] - MEH-PPV were prepared to better study the impact of spectral overlap between the Alq_3 emission and MEH-PPV absorption. It is observed a blue-shift on the photoluminescence of the MEH-PPV/Alq_3 solution system from red-orange (λ_m_a_x = 598 nm) to green (λ_m_a_x = 545 nm) when the radiation dose changes from 0 to 100 Gy. This effect is attributed to the photooxidation process of MEH-PPV and was employed to design dose accumulation sensors in order to represent easily the radiation dose for cancer treatment. (author)

  20. The RaDIATE High-Energy Proton Materials Irradiation Experiment at the Brookhaven Linac Isotope Producer Facility

    Energy Technology Data Exchange (ETDEWEB)

    Ammigan, Kavin; et al.

    2017-05-01

    The RaDIATE collaboration (Radiation Damage In Accelerator Target Environments) was founded in 2012 to bring together the high-energy accelerator target and nuclear materials communities to address the challenging issue of radiation damage effects in beam-intercepting materials. Success of current and future high intensity accelerator target facilities requires a fundamental understanding of these effects including measurement of materials property data. Toward this goal, the RaDIATE collaboration organized and carried out a materials irradiation run at the Brookhaven Linac Isotope Producer facility (BLIP). The experiment utilized a 181 MeV proton beam to irradiate several capsules, each containing many candidate material samples for various accelerator components. Materials included various grades/alloys of beryllium, graphite, silicon, iridium, titanium, TZM, CuCrZr, and aluminum. Attainable peak damage from an 8-week irradiation run ranges from 0.03 DPA (Be) to 7 DPA (Ir). Helium production is expected to range from 5 appm/DPA (Ir) to 3,000 appm/DPA (Be). The motivation, experimental parameters, as well as the post-irradiation examination plans of this experiment are described.

  1. Radiation tolerance study of a commercial 65 nm CMOS technology for high energy physics applications

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Lili, E-mail: lili03.ding@gmail.com [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy); State Key Laboratory of Pulsed Radiation Simulation and Effect, Northwest Institute of Nuclear Technology, Xi' an (China); Gerardin, Simone [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy); Bagatin, Marta [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); Bisello, Dario [Department of Physics and Astronomy, Padova University, Via Marzolo 8, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy); Mattiazzo, Serena [Department of Physics and Astronomy, Padova University, Via Marzolo 8, 35131 Padova (Italy); Paccagnella, Alessandro [Department of Information Engineering, Padova University, Via Gradenigo 6/B, 35131 Padova (Italy); INFN, Padova, Via Marzolo 8, 35131 Padova (Italy)

    2016-09-21

    This paper reports the radiation tolerance study of a commercial 65 nm technology, which is a strong candidate for the Large Hadron Collider applications. After exposure to 3 MeV protons till 1 Grad dose, the 65 nm CMOS transistors, especially the pMOSFETs, showed severe long-term degradation mainly in the saturation drain currents. There were some differences between the degradation levels in the nMOSFETs and the pMOSFETs, which were likely attributed to the positive charges trapped in the gate spacers. After exposure to heavy ions till multiple strikes, the pMOSFETs did not show any sudden loss of drain currents, the degradations in the characteristics were negligible.

  2. Development of approximate shielding calculation method for high energy cosmic radiation on LEO satellites

    International Nuclear Information System (INIS)

    Sin, M. W.; Kim, M. H.

    2002-01-01

    To calculate total dose effect on semi-conductor devices in satellite for a period of space mission effectively, two approximate calculation models for a comic radiation shielding were proposed. They are a sectoring method and a chord-length distribution method. When an approximate method was applied in this study, complex structure of satellite was described into multiple 1-dimensional slabs, structural materials were converted to reference material(aluminum), and the pre-calculated dose-depth conversion function was introduced to simplify the calculation process. Verification calculation was performed for orbit location and structure geometry of KITSAT-1 and compared with detailed 3-dimensional calculation results and experimental values. The calculation results from approximate method were estimated conservatively with acceptable error. However, results for satellite mission simulation were underestimated in total dose rate compared with experimental values

  3. Development of approximate shielding calculation method for high energy cosmic radiation on LEO satellites

    Energy Technology Data Exchange (ETDEWEB)

    Sin, M. W.; Kim, M. H. [Kyunghee Univ., Yongin (Korea, Republic of)

    2002-10-01

    To calculate total dose effect on semi-conductor devices in satellite for a period of space mission effectively, two approximate calculation models for a comic radiation shielding were proposed. They are a sectoring method and a chord-length distribution method. When an approximate method was applied in this study, complex structure of satellite was described into multiple 1-dimensional slabs, structural materials were converted to reference material(aluminum), and the pre-calculated dose-depth conversion function was introduced to simplify the calculation process. Verification calculation was performed for orbit location and structure geometry of KITSAT-1 and compared with detailed 3-dimensional calculation results and experimental values. The calculation results from approximate method were estimated conservatively with acceptable error. However, results for satellite mission simulation were underestimated in total dose rate compared with experimental values.

  4. Recent trends in particle accelerator radiation safety

    International Nuclear Information System (INIS)

    Ohnesorge, W.F.; Butler, H.M.

    1974-01-01

    The use of particle accelerators in applied and research activities continues to expand, bringing new machines with higher energy and current capabilities which create radiation safety problems not commonly encountered before. An overview is given of these increased ionizing radiation hazards, along with a discussion of some of the new techniques required in evaluating and controlling them. A computer search of the literature provided a relatively comprehensive list of publications describing accelerator radiation safety problems and related subjects

  5. Radiating Kerr particle in Einstein universe

    International Nuclear Information System (INIS)

    Vaidya, P.C.; Patel, L.K.

    1989-01-01

    A generalized Kerr-NUT type metric is considered in connection with Einstein field equations corresponding to perfect fluid plus a pure radiation field. A general scheme for obtaining the exact solutions of these field equations is developed. Two physically meaningful particular cases are investigated in detail. One gives the field of a radiating Kerr particle embedded in the Einstein universe. The other solution may probably represent a deSitter-like universe pervaded by a pure radiation field. (author). 7 refs

  6. Soft errors in 10-nm-scale magnetic tunnel junctions exposed to high-energy heavy-ion radiation

    Science.gov (United States)

    Kobayashi, Daisuke; Hirose, Kazuyuki; Makino, Takahiro; Onoda, Shinobu; Ohshima, Takeshi; Ikeda, Shoji; Sato, Hideo; Inocencio Enobio, Eli Christopher; Endoh, Tetsuo; Ohno, Hideo

    2017-08-01

    The influences of various types of high-energy heavy-ion radiation on 10-nm-scale CoFeB-MgO magnetic tunnel junctions with a perpendicular easy axis have been investigated. In addition to possible latent damage, which has already been pointed out in previous studies, high-energy heavy-ion bombardments demonstrated that the magnetic tunnel junctions may exhibit clear flips between their high- and low-resistance states designed for a digital bit 1 or 0. It was also demonstrated that flipped magnetic tunnel junctions still may provide proper memory functions such as read, write, and hold capabilities. These two findings proved that high-energy heavy ions can produce recoverable bit flips in magnetic tunnel junctions, i.e., soft errors. Data analyses suggested that the resistance flips stem from magnetization reversals of the ferromagnetic layers and that each of them is caused by a single strike of heavy ions. It was concurrently found that an ion strike does not always result in a flip, suggesting a stochastic process behind the flip. Experimental data also showed that the flip phenomenon is dependent on the device and heavy-ion characteristics. Among them, the diameter of the device and the linear energy transfer of the heavy ions were revealed as the key parameters. From their dependences, the physical mechanism behind the flip was discussed. It is likely that a 10-nm-scale ferromagnetic disk loses its magnetization due to a local temperature increase induced by a single strike of heavy ions; this demagnetization is followed by a cooling period associated with a possible stochastic recovery process. On the basis of this hypothesis, a simple analytical model was developed, and it was found that the model accounts for the results reasonably well. This model also predicted that magnetic tunnel junctions provide sufficiently high soft-error reliability for use in space, highlighting their advantage over their counterpart conventional semiconductor memories.

  7. Experiments in high energy elementary particle physics and processing of photographically filed data with the aid of a measuring and evaluating system

    Energy Technology Data Exchange (ETDEWEB)

    Kirst, H [Akademie der Wissenschaften der DDR, Berlin-Zeuthen. Inst. fuer Hochenergiephysik

    1977-01-01

    The measuring and evaluating system includes pattern recognition and measuring instruments as well as a processor for data evaluation and checking procedures. The program chart and the application to evaluating photographs of particle tracks from high energy physics experiments are mentioned. The time-sharing effect of such systems in data evaluation is emphasized.

  8. Dictionary of high-energy physics English, German, French, Russian

    International Nuclear Information System (INIS)

    Sube, R.

    1987-01-01

    This volume contains nearly 4500 entries from branches of high-energy physics including cosmic radiation, elementary particles, elementary particle detection and measurement, field theories, and particle accelerators. Each English entry is numbered and followed by corresponding terms in the other languages. Alphabetical indexes of the German, French, and Russian terms are included

  9. High Energy Physics Departments - Overview

    International Nuclear Information System (INIS)

    Bartke, J.

    1999-01-01

    Following the tradition, the activities of the seven new units created in 1997 on the basis of the former Department of High Energy Physics are presented under a common header, they are: Department of Particle Theory (Dept 5); Department of Leptonic Interactions (Dept 11); Department of Hadron Structure (Dept 12); Department of High Energy Nuclear Interactions (Dept 13); The ALICE Experiment Laboratory (NAL); The ATLAS Experiment Laboratory (NAT); High Energy Physics Detector Construction Group (PBD). The research covers a variety of problems of the experimental and theoretical high energy particle physics: the hadronic and leptonic interactions with nucleons and nuclei (characteristics of particle production, including heavy quark physics), e + e - interactions and tests of the Standard Model (also radiative corrections), ultrarelativistic heavy ion interactions and search for the quark-gluon plasma, as well as the spectra, composition and interactions of high energy cosmic ray particles. Research on detectors and accelerator components as well as the development of the apparatus for the high energy physics experiments at future accelerators: LHC (CERN, Geneva), RHIC (Brookhaven), B-Factory (KEK, Tsukuba) and TESLA (DESY) is also presented. The technology of new materials with unique properties such as carbon-carbon composites is also worked on from the point of view of their application in high energy physics experiments. The Division is located in a separate building on the campus of the University of Mining and Metallurgy (UMM). This location, close to the Jagiellonian University (JU), facilitates the collaboration with the latter and with the UMM. The joint weekly seminars carried out for nearly 40 years prove this long term tradition. A substantial part of the activities is teaching and training students from the academic community in Cracow. Joint research, teaching and academic training in the high energy physics are carried out within the M. Miesowicz

  10. Effect of high-energy radiation on composition and feed value of feed-stuffs. 1

    International Nuclear Information System (INIS)

    Nehring, K.; Friedel, K.

    1984-01-01

    The influence of various intensities of gamma radiation on the content of isothiocyanate (ITC), L-5-vinyl-oxazolidine-thione-2 (VOT) and amino acids in rapeseed oilmeal was investigated. Additionally solubility investigations were carried out. In accordance with the results of the decomposition of carbohydrates obtained from plant materials (wood, straw) with a high content of carbohydrates, a distinct effect of irradiation on glucosinolates was detected from 100 kGy onwards, with threshold values for ITC and VOT at doses between 500 and 750 kGy. The influence of γ-rays on the content of amino acids is distinctly lower than on the content of ITC and VOT. Only after doses between 500 and 750 kGy some amino acids decreased within certain limits, particulary methionine, lysine and proline. The solubility of the organic matter and the crude protein of the rapeseed oilmeal changed only little under the influence of various irradiation intensities both in chemical and enzymatic solubility investigations. While the solubility of the organic matter increased under the influence of the growing intensity of irradiation according to the method of crude fiber analysis, it had a falling tendency according to the cellulase method. The solubility of crude protein remained constant according to the pepsin-HCl-method and had again a falling tendency according to the cellulase method. (author)

  11. Bragg-case synchrotron section topography of silicon implanted with high-energy protons and α particles

    International Nuclear Information System (INIS)

    Wieteska, K.; Wierzchowski, W.; Graeff, W.

    1997-01-01

    Back reflection section topography using white-beam synchrotron radiation has been applied for the investigation of silicon implanted with 1 and 1.6 MeV protons and 4.8 MeV α particles. The beam width was limited to 5 μm, and a series of spots in the vicinity of a centrally adjusted reflection were indexed and analysed. The back-reflection section pattern of implanted crystals usually exhibits fringes corresponding to the reflection from the surface and a series of fringes corresponding to the rear region of the shot-through layer, the destroyed layer and the bulk. The patterns were used for direct evaluation of ion ranges and thicknesses of the shot-through layer. The overall characteristics of the obtained patterns were successfully reproduced in simulations based on numerical integration of the Takagi-Taupin equations. The agreement between the simulation and experiment proves that the lattice-parameter depth-distribution profiles can be assumed to be proportional to interstitial-vacancy distributions obtained using the Monte Carlo method from the Biersack-Ziegler theory. The simulation also reproduced interference tails observed in some section patterns. It was found that these tails are caused by the ion-dose change along the beam and they were probably formed due to the interference between the radiation reflected from the bulk and those rays reflected by the rear region of the shot-through layer. (orig.)

  12. Mitigated FPGA design of multi-gigabit transceivers for application in high radiation environments of High Energy Physics experiments

    International Nuclear Information System (INIS)

    Brusati, M.; Camplani, A.; Cannon, M.; Chen, H.; Citterio, M.

    2017-01-01

    SRAM-ba8ed Field Programmable Gate Array (FPGA) logic devices arc very attractive in applications where high data throughput is needed, such as the latest generation of High Energy Physics (HEP) experiments. FPGAs have been rarely used in such experiments because of their sensitivity to radiation. The present paper proposes a mitigation approach applied to commercial FPGA devices to meet the reliability requirements for the front-end electronics of the Liquid Argon (LAr) electromagnetic calorimeter of the ATLAS experiment, located at CERN. Particular attention will be devoted to define a proper mitigation scheme of the multi-gigabit transceivers embedded in the FPGA, which is a critical part of the LAr data acquisition chain. A demonstrator board is being developed to validate the proposed methodology. :!\\litigation techniques such as Triple Modular Redundancy (T:t\\IR) and scrubbing will be used to increase the robustness of the design and to maximize the fault tolerance from Single-Event Upsets (SEUs).

  13. Structuring of material parameters in lithium niobate crystals with low-mass, high-energy ion radiation

    Science.gov (United States)

    Peithmann, K.; Eversheim, P.-D.; Goetze, J.; Haaks, M.; Hattermann, H.; Haubrich, S.; Hinterberger, F.; Jentjens, L.; Mader, W.; Raeth, N. L.; Schmid, H.; Zamani-Meymian, M.-R.; Maier, K.

    2011-10-01

    Ferroelectric lithium niobate crystals offer a great potential for applications in modern optics. To provide powerful optical components, tailoring of key material parameters, especially of the refractive index n and the ferroelectric domain landscape, is required. Irradiation of lithium niobate crystals with accelerated ions causes strong structured modifications in the material. The effects induced by low-mass, high-energy ions (such as 3He with 41 MeV, which are not implanted, but transmit through the entire crystal volume) are reviewed. Irradiation yields large changes of the refractive index Δn, improved domain engineering capability within the material along the ion track, and waveguiding structures. The periodic modification of Δn as well as the formation of periodically poled lithium niobate (PPLN) (supported by radiation damage) is described. Two-step knock-on displacement processes, 3He→Nb and 3He→O causing thermal spikes, are identified as origin for the material modifications.

  14. Respiration and phosphorylation in liver and kidney mitochondria of rats exposed to high-energy gamma and beta radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mokhoreva, S I; Vetlugina, N S

    1973-01-01

    The effect of whole-body irradiation with ..gamma.. rays (radiation source /sup 60/Co) at 40 rad and ..beta.. rays (source, a linear accelerator, electron energy 25 MeV) at 43 rad on oxidative phosphorylation in liver and kidney mitochondria was studied in rats. Gamma radiation gradually slowed the esterification of phosphate and respiratory rate during the oxidation of succinate in the liver and kidney mitochondria. The decrease was largest on day 15 after irradiation. However, the P/O ratio did not decrease by more than 10 to 12 percent. Despite the oxidation of glutamate in the mitochondria, respiration, phosphate consumption, and P/O ratio scarcely changed. Irradiation with electrons slowed the rate of oxidation of succinate and glutamate in liver mitochondria within 3 to 7 days. Phosphate consumption decreased at the same time so that the P/O ratio remained unchanged. Beta irradiation had virtually no effect on liver mitochondria. There is a discussion of the mechanism of action of high-energy radiation on the phosphorylation system of the mitochondria.

  15. Device for imaging an object by means of masks of spatially modulable electromagnetic radiation or corpuscular radiation of high energy

    International Nuclear Information System (INIS)

    Barrett, H.H.

    1979-01-01

    The radiogram of the thyroid is produced by means of a detector device operating similar to a scintillation camera. Between thyroid and detector device there is placed a mask having modulating areas, permeable and impermeable to radiation succeeding each other with decreasing extension. The scanning signal has got the shape of a radar signal with chirp modulation. The filtering unit used for it is a pulse compression filter. The image of the radiation energy distribution on the recording surface of the detector device is thus decoded and compressed to a number of image points giving the picture of the thyroid. (RW) [de

  16. Results of Gamma-Ray Imaging with High-Energy Radiation Visualizer HERV at Nuclear Reactor in Russia and Germany

    International Nuclear Information System (INIS)

    Ivanov, O.P.; Stepanov, V.E.; Sudarkin, A.N.; Urutskoev, L.I.

    1999-01-01

    HER V-high energy radiation visualizer is a system for imaging in X-and gamma-ray regions developed by RECOM during recent years. Its later version provides the real industrial prototype that has been already tested under the complex gamma-field conditions of highly contaminated nuclear facilities in Russia and Germany. New special options for initial CCD camera frames processing (CCD camera operates in slow repetition mode) allow one to perform imaging without heavy shielding during a long exposure time. Image processing options allowing one to take into account background radiation, noise and drift of electronics are described. The contaminated pipelines and vessels HER V imagery results are presented. Background does rate in rooms with contaminated equipment appeared to be up to 1 R/hour and from 1m R/hour up to 50 m R/hour at detector's head location. The major contaminating nuclides proved to be Co-60 and Cs-137. Imaging time was chosen to be 0.2-1 hour. Data acquisition and processing procedures enabled to avoid the high background dose rate influence at the device measuring head location. Superposition of gamma images over optical images indicates that the major contaminated parts of the pipelines were their bends, places of their connection, and their valves

  17. Calibration of solid state nuclear track detectors at high energy ion beams for cosmic radiation measurements: HAMLET results

    International Nuclear Information System (INIS)

    Szabó, J.; Pálfalvi, J.K.

    2012-01-01

    The MATROSHKA experiments and the related HAMLET project funded by the European Commission aimed to study the dose burden of the crew working on the International Space Station (ISS). During these experiments a human phantom equipped with several thousands of radiation detectors was exposed to cosmic rays inside and outside the ISS. Besides the measurements realized in Earth orbit, the HAMLET project included also a ground-based program of calibration and intercomparison of the different detectors applied by the participating groups using high-energy ion beams. The Space Dosimetry Group of the Centre for Energy Research (formerly Atomic Energy Research Institute) participated in these experiments with passive solid state nuclear track detectors (SSNTDs). The paper presents the results of the calibration experiments performed in the years 2008–2011 at the Heavy Ion Medical Accelerator (HIMAC) of the National Institute of Radiological Sciences (NIRS), Chiba, Japan. The data obtained serve as update and improvement for the previous calibration curves which are necessary for the evaluation of the SSNTDs exposed in unknown space radiation fields.

  18. Calibration of solid state nuclear track detectors at high energy ion beams for cosmic radiation measurements: HAMLET results

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, J., E-mail: julianna.szabo@energia.mta.hu [Hungarian Academy of Sciences, Centre for Energy Research, Konkoly Thege Miklos ut 29-33, 1525 Budapest 114, P.O. Box 49 (Hungary); Palfalvi, J.K. [Hungarian Academy of Sciences, Centre for Energy Research, Konkoly Thege Miklos ut 29-33, 1525 Budapest 114, P.O. Box 49 (Hungary)

    2012-12-01

    The MATROSHKA experiments and the related HAMLET project funded by the European Commission aimed to study the dose burden of the crew working on the International Space Station (ISS). During these experiments a human phantom equipped with several thousands of radiation detectors was exposed to cosmic rays inside and outside the ISS. Besides the measurements realized in Earth orbit, the HAMLET project included also a ground-based program of calibration and intercomparison of the different detectors applied by the participating groups using high-energy ion beams. The Space Dosimetry Group of the Centre for Energy Research (formerly Atomic Energy Research Institute) participated in these experiments with passive solid state nuclear track detectors (SSNTDs). The paper presents the results of the calibration experiments performed in the years 2008-2011 at the Heavy Ion Medical Accelerator (HIMAC) of the National Institute of Radiological Sciences (NIRS), Chiba, Japan. The data obtained serve as update and improvement for the previous calibration curves which are necessary for the evaluation of the SSNTDs exposed in unknown space radiation fields.

  19. The high energy astronomy observatories

    Science.gov (United States)

    Neighbors, A. K.; Doolittle, R. F.; Halpers, R. E.

    1977-01-01

    The forthcoming NASA project of orbiting High Energy Astronomy Observatories (HEAO's) designed to probe the universe by tracing celestial radiations and particles is outlined. Solutions to engineering problems concerning HEAO's which are integrated, yet built to function independently are discussed, including the onboard digital processor, mirror assembly and the thermal shield. The principle of maximal efficiency with minimal cost and the potential capability of the project to provide explanations to black holes, pulsars and gamma-ray bursts are also stressed. The first satellite is scheduled for launch in April 1977.

  20. High energy physics and cosmology

    International Nuclear Information System (INIS)

    Silk, J.I.

    1991-01-01

    This research will focus on the implications of recent theories and experiments in high energy physics of the evolution of the early universe, and on the constraints that cosmological considerations can place on such theories. Several problems are under investigation, including studies of the nature of dark matter and the signature of annihilations in the galactic halo, where the resulting γ-ray fluxes are potentially observable, and in stars, where stellar evolution may be affects. We will develop constraints on the inflationary predictions of scale-free primordial fluctuations in a universe at critical closure density by studying their linear and non-linear evolution after they re-enter the particle horizon, examining the observable imprint of primordial density fluctuations on the cosmic microwave background radiation in both flat and curved cosmological models, and implications for observations of large-scale galaxy clustering and structure formation theories. We will also study spectral distortions in the microwave background radiation that are produced by exotic particle decays in the very early universe. We expect such astrophysical considerations to provide fruitful insights both into high-energy particle physics and into possible cosmological for the early universe

  1. Particle penetration and radiation effects

    CERN Document Server

    Sigmund, Peter

    This book, which has evolved from the author’s lectures at the University of Copenhagen and the University of Southern Denmark, draws on his experience as an active researcher in the interaction of charged particles with matter over more than forty years. The emphasis is on the theoretical description of fundamental phenomena, and much attention has been given to classic topics such as: Rutherford scattering; the theory of particle stopping as developed by Bohr, Bethe, Bloch and Lindhard; the statistical description of energy loss as developed by Bohr, Bothe, Williams and Landau; and numerous more recent developments. An attempt has been made to provide at least one complete derivation of a theoretical description for all central aspects. The presentation is intended to respect the ideas of the original authors, but much effort has been invested in establishing a unified and appealing notation consistent with present-day standards. It is intended that this volume will satisfy a long-standing need for a text...

  2. From the numerics of dynamics to the dynamics of numerics and visa versa in high energy particle physics

    International Nuclear Information System (INIS)

    Zhong Ting

    2009-01-01

    Starting from the concepts of statistical symmetry we consider different aspects of the connections between nonlinear dynamics and high energy physics. We pay special attention to the interplay between number theory and dynamics. We subsequently utilize the so obtained insight to compute vital constants relevant to the program of grand unification and quantum gravity.

  3. High energy beam impact tests on a LHC tertiary collimator at the CERN high-radiation to materials facility

    Directory of Open Access Journals (Sweden)

    Marija Cauchi

    2014-02-01

    Full Text Available The correct functioning of a collimation system is crucial to safely operate highly energetic particle accelerators, such as the Large Hadron Collider (LHC. The requirements to handle high intensity beams can be demanding. In this respect, investigating the consequences of LHC particle beams hitting tertiary collimators (TCTs in the experimental regions is a fundamental issue for machine protection. An experimental test was designed to investigate the robustness and effects of beam accidents on a fully assembled collimator, based on accident scenarios in the LHC. This experiment, carried out at the CERN High-Radiation to Materials (HiRadMat facility, involved 440 GeV proton beam impacts of different intensities on the jaws of a horizontal TCT. This paper presents the experimental setup and the preliminary results obtained, together with some first outcomes from visual inspection and a comparison of such results with numerical simulations.

  4. High energy beam impact tests on a LHC tertiary collimator at the CERN high-radiation to materials facility

    Science.gov (United States)

    Cauchi, Marija; Aberle, O.; Assmann, R. W.; Bertarelli, A.; Carra, F.; Cornelis, K.; Dallocchio, A.; Deboy, D.; Lari, L.; Redaelli, S.; Rossi, A.; Salvachua, B.; Mollicone, P.; Sammut, N.

    2014-02-01

    The correct functioning of a collimation system is crucial to safely operate highly energetic particle accelerators, such as the Large Hadron Collider (LHC). The requirements to handle high intensity beams can be demanding. In this respect, investigating the consequences of LHC particle beams hitting tertiary collimators (TCTs) in the experimental regions is a fundamental issue for machine protection. An experimental test was designed to investigate the robustness and effects of beam accidents on a fully assembled collimator, based on accident scenarios in the LHC. This experiment, carried out at the CERN High-Radiation to Materials (HiRadMat) facility, involved 440 GeV proton beam impacts of different intensities on the jaws of a horizontal TCT. This paper presents the experimental setup and the preliminary results obtained, together with some first outcomes from visual inspection and a comparison of such results with numerical simulations.

  5. On the unification of all fundamental forces in a fundamentally fuzzy Cantorian ε(∞) manifold and high energy particle physics

    International Nuclear Information System (INIS)

    Marek-Crnjac, L.

    2004-01-01

    Quantum space time as given by topology and geometry of El Naschie's ε (∞) theory must be regarded as fundamentally fuzzy. It's geometry and topology belong to the mathematical category of fuzzy logic and fuzzy set theory. All lines are fuzzy fractal lines in fuzzy spaces and all exact values are exact fuzzy expectation values. That way we remove many paradoxes and contradictions in the standard model of high energy particle physics

  6. Transition radiation of ultrarelativistic neutral particles

    International Nuclear Information System (INIS)

    Grimus, W.; Neufeld, H.

    1994-10-01

    We perform a quantum theoretical calculation of transition radiation by neutral particles with spin 1/2 equipped with magnetic moments and/or electric dipole moments. The limit of vanishing masses is treated exactly for arbitrary refraction index. Finally we apply our result to the solar neutrino flux. (author)

  7. Potential for heavy particle radiation therapy

    International Nuclear Information System (INIS)

    Raju, M.R.; Phillips, T.L.

    1977-03-01

    Radiation therapy remains one of the major forms of cancer treatment. When x rays are used in radiotherapy, there are large variations in radiation sensitivity among tumors because of the possible differences in the presence of hypoxic but viable tumor cells, differences in reoxygenation during treatment, differences in distribution of the tumor cells in their cell cycle, and differences in repair of sublethal damage. When high-LET particles are used, depending upon the LET distribution, these differences are reduced considerably. Because of these differences between x rays and high-LET particle effects, the high-LET particles may be more effective on tumor cells for a given effect on normal cells. Heavy particles have potential application in improving radiotherapy because of improved dose localization and possible advantages of high-LET particles due to their radiobiological characteristics. Protons, because of their defined range, Bragg peak, and small effects of scattering, have good dose localization characteristics. The use of protons in radiotherapy minimizes the morbidity of radiotherapy treatment and is very effective in treating deep tumors located near vital structures. Fast neutrons have no physical advantages over 60 Co gamma rays but, because of their high-LET component, could be very effective in treating tumors that are resistant to conventional radiations. Negative pions and heavy ions combine some of the advantages of protons and fast neutrons

  8. A Self-Powered Thin-Film Radiation Detector Using Intrinsic High-Energy Current (HEC) (Author’s Final Version)

    Science.gov (United States)

    2016-09-08

    of electromagnetic 85 pulse effects on cables and electrical devices4 and as a self - powered detector for in-core neutron flux measurement in nuclear...AFCEC-CX-TY-TP-2016-0003 A SELF - POWERED THIN-FILM RADIATION DETECTOR USING INTRINSIC HIGH-ENERGY CURRENT (HEC) (AUTHOR’S FINAL VERSION...14 -- 5 Oct 15 A self - powered thin-film radiation detector using intrinsic high-energy current (HEC) (Author’s Final Version) FA8051-15-P-0010

  9. [High energy particle physics]: Progress report covering the period from August 1, 1987 to July 31, 1988

    International Nuclear Information System (INIS)

    1988-01-01

    In this document the High Energy Physics Group reviews its accomplishments and progress during the past year and presents plans for continuing research during the next several years. Some of the topics discussed in this report are: completed fixed target experiments; applications of QCD to hard hadronic processes; top quark signatures at the Tevatron collider; searching for supersymmetry at e + e/sup /minus// colliders; Monte Carlo simulations; and quantrum field theories

  10. High-altitude cosmic ray neutrons: probable source for the high-energy protons of the earth's radiation belts

    International Nuclear Information System (INIS)

    Hajnal, F.; Wilson, J.

    1992-01-01

    'Full Text:' Several High-altitude cosmic-ray neutron measurements were performed by the NASA Ames Laboratory in the mid-to late-1970s using airplanes flying at about 13km altitude along constant geomagnetic latitudes of 20, 44 and 51 degrees north. Bonner spheres and manganese, gold and aluminium foils were used in the measurements. In addition, large moderated BF-3 counters served as normalizing instruments. Data analyses performed at that time did not provide complete and unambiguous spectral information and field intensities. Recently, using our new unfolding methods and codes, and Bonner-sphere response function extensions for higher energies, 'new' neutron spectral intensities were obtained, which show progressive hardening of neutron spectra as a function of increasing geomagnetic latitude, with substantial increases in the energy region iron, 1 0 MeV to 10 GeV. For example, we found that the total neutron fluences at 20 and 51 degrees magnetic north are in the ratio of 1 to 5.2 and the 10 MeV to 10 GeV fluence ratio is 1 to 18. The magnitude of these ratios is quite remarkable. From the new results, the derived absolute neutron energy distribution is of the correct strength and shape for the albedo neutrons to be the main source of the high-energy protons trapped in the Earth's inner radiation belt. In addition, the results, depending on the extrapolation scheme used, indicate that the neutron dose equivalent rate may be as high as 0.1 mSv/h near the geomagnetic north pole and thus a significant contributor to the radiation exposures of pilots, flight attendants and the general public. (author)

  11. Research in high energy physics

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses research being conducted in high energy physics in the following areas; quantum chromodynamics; drift chambers; proton-antiproton interactions; particle decays; particle production; polarimeters; quark-gluon plasma; and conformed field theory

  12. Research in high energy physics

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses research being conducted in high energy physics in the following areas: quantum chromodynamics; drift chambers; proton-antiproton interactions; particle decays; particle production; polarimeters; quark-gluon plasma; and conformed field theory

  13. Multiplicity distribution and multiplicity moment of black and grey particles in high energy nucleus–nucleus interactions

    International Nuclear Information System (INIS)

    Ghosh, Dipak; Deb, Argha; Datta, Utpal; Bhattacharyya, S.

    2011-01-01

    In this paper we have studied the multiplicity distribution of black and grey particles emitted from 16 O–AgBr interactions at 2.1 AGeV and 60 AGeV. We have also calculated the multiplicity moment up to the fifth order for both the interactions and for both kinds of emitted particles. The variation of multiplicity moment with the order number has been investigated. It is seen that in the case of black particles multiplicity moment up to fourth order remains almost constant as energy increases from 2.1 AGeV to 60 AGeV. Fifth order multiplicity moment increases insignificantly with energy. However in the case of grey particles no such constancy of multiplicity moment with energy of the projectile beam is obtained. Later we have extended our study on the basis of Regge–Mueller approach to find the existence of second order correlation during the emission of black as well as the grey particles. The second Mueller moment is found to be positive and it increases as energy increases in the case of black particles. On the contrary in the case of grey particles the second Mueller moment decreases with energy. It can be concluded that as energy increases correlation among the black particles increases. On the other hand with the increase of energy correlation among the grey particles is found to diminish. (author)

  14. Smoothed Particle Hydrodynamics Coupled with Radiation Transfer

    Science.gov (United States)

    Susa, Hajime

    2006-04-01

    We have constructed a brand-new radiation hydrodynamics solver based upon Smoothed Particle Hydrodynamics, which works on a parallel computer system. The code is designed to investigate the formation and evolution of first-generation objects at z ≳ 10, where the radiative feedback from various sources plays important roles. The code can compute the fraction of chemical species e, H+, H, H-, H2, and H+2 by by fully implicit time integration. It also can deal with multiple sources of ionizing radiation, as well as radiation at Lyman-Werner band. We compare the results for a few test calculations with the results of one-dimensional simulations, in which we find good agreements with each other. We also evaluate the speedup by parallelization, which is found to be almost ideal, as long as the number of sources is comparable to the number of processors.

  15. Analyses of the Secondary Particle Radiation and the DNA Damage it Causes to Human Keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lebel E. A.; Tafrov S.; Rusek, A.; Sivertz, M. B.; Yip, K.; Thompson, K. H.

    2011-11-01

    High-energy protons, and high mass and energy ions, along with the secondary particles they produce, are the main contributors to the radiation hazard during space explorations. Skin, particularly the epidermis, consisting mainly of keratinocytes with potential for proliferation and malignant transformation, absorbs the majority of the radiation dose. Therefore, we used normal human keratinocytes to investigate and quantify the DNA damage caused by secondary radiation. Its manifestation depends on the presence of retinol in the serum-free media, and is regulated by phosphatidylinositol 3-kinases. We simulated the generation of secondary radiation after the impact of protons and iron ions on an aluminum shield. We also measured the intensity and the type of the resulting secondary particles at two sample locations; our findings agreed well with our predictions. We showed that secondary particles inflict DNA damage to different extents, depending on the type of primary radiation. Low-energy protons produce fewer secondary particles and cause less DNA damage than do high-energy protons. However, both generate fewer secondary particles and inflict less DNA damage than do high mass and energy ions. The majority of cells repaired the initial damage, as denoted by the presence of 53BPI foci, within the first 24 hours after exposure, but some cells maintained the 53BP1 foci longer.

  16. Particles colliders at the Large High Energy Laboratories; Colisionadores de particulas en los grandes laboratorios de Fisica de Altas Energias

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, M

    1996-09-01

    In this work we present an elementary introduction to particle accelerators, a basic guide of existing colliders and a description of the large european laboratories devoted to Elementary Particle Physics. This work is a large, corrected and updated version of an article published in: Ciencia-Tecnologia-Medio Ambiente Annual report 1996 Edition el Pais (Author)

  17. Coordinates for Representing Radiation Belt Particle Flux

    Science.gov (United States)

    Roederer, Juan G.; Lejosne, Solène

    2018-02-01

    Fifty years have passed since the parameter "L-star" was introduced in geomagnetically trapped particle dynamics. It is thus timely to review the use of adiabatic theory in present-day studies of the radiation belts, with the intention of helping to prevent common misinterpretations and the frequent confusion between concepts like "distance to the equatorial point of a field line," McIlwain's L-value, and the trapped particle's adiabatic L* parameter. And too often do we miss in the recent literature a proper discussion of the extent to which some observed time and space signatures of particle flux could simply be due to changes in magnetospheric field, especially insofar as off-equatorial particles are concerned. We present a brief review on the history of radiation belt parameterization, some "recipes" on how to compute adiabatic parameters, and we illustrate our points with a real event in which magnetospheric disturbance is shown to adiabatically affect the particle fluxes measured onboard the Van Allen Probes.

  18. Correlative degree and collective side ward flow of final state particles in high energy heavy ion collisions

    International Nuclear Information System (INIS)

    Zhang Weigang

    1999-01-01

    A concept of correlative degree is proposed. Using the method of particle-group correlation's function, the effects of the particles with different correlative degrees on collective side ward flow are studied for 1.2A GeV Ar + Bal 2 collisions at the Bevalac stream chamber. The studies indicate that correlative degree is an important parameter on describing collective side ward flow properties. The minority of correlative particles (or fragments) with larger correlative degrees can produce the effect arising from the collective side ward flow, but the effect arising from high-order collective flow correlations can not be dominated by these minority of particles (or fragments). It is results from the collective contribution of the majority of collective particles (or fragments) with various correlative degrees

  19. Topological background on charmed and beauty particle pairs produced in high energy hadron interactions in nuclear emulsions

    International Nuclear Information System (INIS)

    Romano, G.

    1984-01-01

    This chapter demonstrates that by making use of the fact that new flavors must be produced in pairs in strong interactions and that beauty particles are expected to decay often into charmed particles, the contribution of background simulating decays can be computed from a pure topological point of view. Topics covered include the emulsion data, the search for charmed particles, the search for beauty particles, detection efficiency, and the evaluation of mean life-time. It is assumed that in the interaction of (350-400) GeV hadrons in emulsion the production rate of charmed particle pairs is 5X10 -3 /interaction. The corresponding figures for BB production are estimated to be 10 3 times smaller. It is noted that some neutral decay topology, like 4 or more charged prongs, are much less affected by background

  20. Method of determining the partial cross sections in a heavy liquid. Application to the production of strange particles by high energy π"-

    International Nuclear Information System (INIS)

    Lloret, Antonio

    1964-01-01

    This research thesis reports the study if the measurement of cross sections on proton, and more particularly the development of a method of determination of cross sections which takes problems raised by a heavy liquid into account. This method is applied with sufficiently high energies for the Fermi momentum to have no influence on cross sections. The author first presents the general method of determination of partial cross sections in a heavy liquid: case of a hydrogen chamber, ideal case of a heavy liquid chamber without possibility of secondary interactions nor evaporations, search for a formula removing secondary interactions, correction due to the fact that the number of neutrons is not equal to the number of protons in the mixture nuclei, application to cross sections of production of high energy strange particles, calculation of the number of produced high energy particles. The experiment is then presented with its chamber, its measurement and calculation techniques. The author then reports and discusses cross section calculations and compares results with those of previous experiments. The last part addresses the study of secondary interactions in nuclei

  1. Measurement of continuous x-radiation and determination of the energy distribution function of high-energy electrons from an ECR plasma

    International Nuclear Information System (INIS)

    Bernhardi, K.

    1980-01-01

    Investigations were made on the x-radiation emitted by a plasma. The methods applied here represent a further development of experimental and numerical methods used hitherto for determining the bremsstrahlung emitted by a plasma, and makes possible a more precise determination of the high-energy electron component of a plasma

  2. High energy physics problems

    International Nuclear Information System (INIS)

    Arbuzov, B.A.

    1977-01-01

    Described are modern views on the particle structure and particle interactions at high energies. According to the latest data recieved, all particles can be classified in three groups: 1) strong interacting hadrons; 2) leptons, having no strong interactions; 3) photon. The particle structure is described in a quark model, and with the use of gluons. The elementary particle theory is based on the quantum field theory. The energy increase of interacting particles enables to check the main theory principles, such as conventions for causality, relativistic invariance and unitarity. Investigations of weak interactions are of great importance. The progress in this field is connected with unified gauge theories of weak and electromagnetic interactions. For weak interactions promissing are the experiments with colliding electron-proton rings. The new data, especially at higher energies, will lead to a further refinement of the nature of particles and their interactions

  3. Detection of high energy gamma radiations with liquid rare gases as scintillators; Detection des rayonnements Gamma de grande energie avec les gaz rares liquides comme scintillateurs

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Phan Xuan

    1965-11-25

    This research thesis reports the study of a sensor based on a liquid scintillator for the detection of high energy (10 to 30 MeV) gamma radiations. The scintillator is a liquefied argon or xenon rare gas. The author first studies the process of energy transfer from the particle to the sensing medium. He addresses the different involved elements and phenomena: electromagnetic radiations (Compton Effect, photoelectric effect, pair production, and total gamma absorption), charged particles (braking radiation, collisions) and application to gamma spectrometry. He describes and discusses the scintillation mechanisms (scintillation of organic and inorganic materials), the general characteristics of scintillators (impurities, converters), and then reports the practical realisation of the sensor. Results are presented and discussed [French] Dans ce travail, nous nous proposons d'etudier une technique. Il s'agit d'un detecteur a scintillateur liquide pour la detection des rayonnements gamma energiques (10 a 30 MeV). Le scintillateur utilise est un gaz rare liquefie argon ou xenon. Nous examinerons d'abord les processus de transfert de l'energie de la particule au milieu detecteur puis les mecanismes de scintillation en general pour pouvoir exploiter au mieux les phenomenes favorables. Nous presenterons ensuite la realisation pratique du detecteur. Ses qualites (et defauts) trouveront leur place dans la fin de ce memoire. Bien qu'a l'heure actuelle, par la methode de Kyropoulos, on puisse faire pousser des gros cristaux d'iodure de sodium, l'utilisation des 'gaz rares' liquefies comme scintillateurs est, grace a la brievete de la scintillation, tres utile lorsqu'on recherche un fort taux de comptage (jusqu'a 10 impulsions par seconde) ou lorsqu'on veut resoudre certains problemes de coincidence. Les cristaux NaI(Tl) de grandes dimensions sont d'un montage facile mais leur manipulation requiert beaucoup de precautions du fait qu'ils supportent tres mal les chocs thermiques

  4. Quantitative evaluation of high-energy O− ion particle flux in a DC magnetron sputter plasma with an indium-tin-oxide target

    International Nuclear Information System (INIS)

    Suyama, Taku; Bae, Hansin; Setaka, Kenta; Ogawa, Hayato; Fukuoka, Yushi; Suzuki, Haruka; Toyoda, Hirotaka

    2017-01-01

    O − ion flux from the indium tin oxide (ITO) sputter target under Ar ion bombardment is quantitatively evaluated using a calorimetry method. Using a mass spectrometer with an energy analyzer, O − energy distribution is measured with spatial dependence. Directional high-energy O − ion ejected from the target surface is observed. Using a calorimetry method, localized heat flux originated from high-energy O − ion is measured. From absolute evaluation of the heat flux from O − ion, O − particle flux in order of 10 18 m −2 s −1 is evaluated at a distance of 10 cm from the target. Production yield of O − ion on the ITO target by one Ar + ion impingement at a kinetic energy of 244 eV is estimated to be 3.3  ×  10 −3 as the minimum value. (paper)

  5. Quantitative evaluation of high-energy O- ion particle flux in a DC magnetron sputter plasma with an indium-tin-oxide target

    Science.gov (United States)

    Suyama, Taku; Bae, Hansin; Setaka, Kenta; Ogawa, Hayato; Fukuoka, Yushi; Suzuki, Haruka; Toyoda, Hirotaka

    2017-11-01

    O- ion flux from the indium tin oxide (ITO) sputter target under Ar ion bombardment is quantitatively evaluated using a calorimetry method. Using a mass spectrometer with an energy analyzer, O- energy distribution is measured with spatial dependence. Directional high-energy O- ion ejected from the target surface is observed. Using a calorimetry method, localized heat flux originated from high-energy O- ion is measured. From absolute evaluation of the heat flux from O- ion, O- particle flux in order of 1018 m-2 s-1 is evaluated at a distance of 10 cm from the target. Production yield of O- ion on the ITO target by one Ar+ ion impingement at a kinetic energy of 244 eV is estimated to be 3.3  ×  10-3 as the minimum value.

  6. Particles in spherical electromagnetic radiation fields

    International Nuclear Information System (INIS)

    Mitter, H.; Thaller, B.

    1984-03-01

    If the time-dependence of a Hamiltonian can be compensated by an appropriate symmetry transformation, the corresponding quantum mechanical problem can be reduced to an effectively stationary one. With this result we investigate the behavior of nonrelativistic particles in a spherical radiation field produced by a rotating source. Then the symmetry transformation corresponds to a rotation. We calculate the transition probabilities in Born approximation. The extension to problems involving an additional Coulomb potential is briefly discussed. (Author)

  7. First results of high energy particle measurements with the TUENDE-M telescopes on board the S/C VEGA-1 and -2

    International Nuclear Information System (INIS)

    Somogyi, A.J.; Erdoes, G.; Eroe, J.

    1986-02-01

    VEGA-1 and VEGA-2 space probes launched to comet Halley are equipped with identical TUENDE-M high energy particle detectors. Each TUENDE-M instrument consists of two particle telescopes viewing in the ecliptic plane at an angle of deg 55 and deg 90, respectively, to the east of the Sun. Technical data of the detectors are tabulated. In the period Dec 1984 - Apr 1985 several cases of interplanetary acceleration of charged particles up to MeV energies and a large solar flare event (27.Jan 1985) were observed by the TUENDE-M instruments. The latter event is described in detail and observation results (intensity profiles of different channels of various energies) are presented. (D.Gy.)

  8. Detector for atomic particles and ionizing radiations

    International Nuclear Information System (INIS)

    Mallet, Georges; Ythier, Christian.

    1976-01-01

    The aim of this invention is to provide improved detectors of atomic particles and of ionising radiations, having maximum sensitivity, by virtually suppressing all absorption of the radiation scattered by the main detector, so that these detectors are particularly suitable for fitting to anti-Compton spectrometers. Reference is particularly made to detectors of the Ge(Li) type, lithium compensated germanium, which are the most used. It is however made clear that this choice is not restrictive and that this invention not only applies to all known types of detectors and particularly to scintillator detectors, for instance to detectors such as NaI (Tl), composed of a monocrystal of a thallium activated alkaline halogenide, but also to gas, ionisation chamber and luminescent chamber type detectors and in general to all the known devices that convert the energy of particles into electric signals. Owing to the fact that the walls of the enclosure containing the main detector are composed, in the part around this detector, of an auxiliary detector, the latter detects virtually all the radiations scattered by the main detector. It does so without any loss due to the absorption of these radiations (a) by the metal walls of the enclosure usually containing the main detector and (b) by the walls of the auxiliary detector casing. It results from this that the detectors of the invention enable coincidence or anti-coincidence spectrometers with a very high performance to be made [fr

  9. Astrophysics at very high energies

    International Nuclear Information System (INIS)

    Aharonian, Felix; Bergstroem, Lars; Dermer, Charles

    2013-01-01

    Presents three complementary lectures on very-high-energy astrophysics given by worldwide leaders in the field. Reviews the recent advances in and prospects of gamma-ray astrophysics and of multi-messenger astronomy. Prepares readers for using space and ground-based gamma-ray observatories, as well as neutrino and other multi-messenger detectors. With the success of Cherenkov Astronomy and more recently with the launch of NASA's Fermi mission, very-high-energy astrophysics has undergone a revolution in the last years. This book provides three comprehensive and up-to-date reviews of the recent advances in gamma-ray astrophysics and of multi-messenger astronomy. Felix Aharonian and Charles Dermer address our current knowledge on the sources of GeV and TeV photons, gleaned from the precise measurements made by the new instrumentation. Lars Bergstroem presents the challenges and prospects of astro-particle physics with a particular emphasis on the detection of dark matter candidates. The topics covered by the 40th Saas-Fee Course present the capabilities of current instrumentation and the physics at play in sources of very-high-energy radiation to students and researchers alike. This book will encourage and prepare readers for using space and ground-based gamma-ray observatories, as well as neutrino and other multi-messenger detectors.

  10. Curvature radiation by bunches of particles

    International Nuclear Information System (INIS)

    Saggion, A.

    1975-01-01

    A bunch of relativistic particles moving on a curved trajectory is considered. The coherent emission of curvature radiation is described with particular regard to the role played by the 'shape' of the bunch as a function of its dimensions. It is found that the length of the bunch strongly affects the spectrum of the radiation emitted, with no effect on its polarization. For wavelengths shorter than the length of the bunch, the emitted intensity as a function of frequency shows recurrent maxima and minima, the height of the maxima being proportional to νsup(-5/3). The bunch dimensions perpendicular to the plane of the orbit affect both the spectral intensity and the polarization of the radiation. (orig./BJ) [de

  11. High Energy Physics Departments - Overview

    International Nuclear Information System (INIS)

    Bartke, J.

    2000-01-01

    Full text: Following our long-time tradition we will present under a common header the activities of the seven new units created in 1997 on the basis of the former Department of High Energy Physics: Department of Particle Theory (Dept. V); Department of Leptonic Interactions (Dept XI); Department of Hadron Structure (Dept XII); Department of High Energy Nuclear Interactions (Dept XIII); The ALICE Experiment Laboratory (NAL); The ATLAS Experiment Laboratory (NAT); High Energy Physics Detector Construction Group (PBD). At the end we will list our common activities: lectures and courses as well as seminars. Our research covers a variety of problems of the experimental and theoretical high energy particle physics: the hadronic and leptonic interactions with nucleons and nuclei (characteristics of particle production, including heavy quark physics), e + e - interactions and tests of the Standard Model (also evaluation of radiative corrections), ultrarelativistic heavy ion interactions and search for the quark-gluon plasma, as well as the spectra, composition and interactions of high energy cosmic ray particles. Research on detectors and accelerator components as well as the development of the apparatus for the high energy physics experiments at future accelerators: LHC (CERN, Geneva), RHIC (Brookhaven), B-Factory (KEK, Tsukuba) and TESLA (DESY, Hamburg) is also carried out. The technology of new materials with unique properties such as carbon-carbon composites is also worked on from the point of view of their application in high energy physics experiments. The Division is located in a separate building on the campus of the University of Mining and Metallurgy. This location, close to the Jagiellonian University, facilitates the collaboration with the latter and with the University of Mining and Metallurgy. The joint weekly seminars carried out for nearly 40 years prove this long term tradition. A substantial part of our activities is teaching and training students from

  12. High energy photon reference for radiation protection: technical design of the LINAC beam and ionization chambers; and calculation of monoenergetic conversion coefficients

    Directory of Open Access Journals (Sweden)

    Dusciac D.

    2016-01-01

    Full Text Available In this work, we present the results of the first part of a research project aimed at offering a complete response to dosimeters providers and nuclear physicists’ demands for high-energy (6 – 9 MeV photon beams for radiation protection purposes. Classical facilities allowing the production of high-energy photonic radiation (proton accelerators, nuclear reactors are very rare and need large investment for development and use. A novel solution is proposed, consisting in the use of a medical linear accelerator, allowing a significant decrease of all costs.Using Monte Carlo simulations (MCNP5 and PENELOPE codes, a specifically designed electron-photon conversion target allowing for obtaining a high energy photon beam (with an average energy weighted by fluence of about 6 MeV has been built for radiation protection purposes. Due to the specific design of the target, this “realistic” radiation protection high-energy photon beam presents a uniform distribution of air kerma rate at a distance of 1 m, over a 30 × 30 cm2 surface. Two graphite cavity ionizing chambers for ionometric measurements have been built. For one of these chambers, the charge collection volume has been measured allowing for its use as a primary standard. The second ionizing chamber is used as a transfer standard; as such it has been calibrated in a 60Co beam, and in the high energy photon beam for radiation protection.The measurements with these ionizing chambers allowed for an evaluation of the air kerma rate in the LINAC based high-energy photon beam for radiation protection: the values cover a range between 36 mGy/h and 210 mGy/h, compatible with radiation protection purposes.Finally, using Monte Carlo simulations, conversion coefficients from air kerma to dose equivalent quantities have been calculated in the range between 10 keV and 22.4 MeV, for the spectral distribution of the fluence corresponding to the beam produced by the linear accelerator of the LNE-LNHB.

  13. Effects of high-energy particle showers on the embedded front-end electronics of an electromagnetic calorimeter for a future lepton collider

    Czech Academy of Sciences Publication Activity Database

    Adloff, C.; Francis, K.; Repond, J.; Marčišovský, Michal; Šícho, Petr; Vrba, Václav; Zálešák, Jaroslav

    2011-01-01

    Roč. 654, č. 1 (2011), s. 97-109 ISSN 0168-9002 R&D Projects: GA MŠk LA09042; GA MŠk LA08032 Grant - others:EC(XE) RII3-CT-2006-026126 Institutional research plan: CEZ:AV0Z10100502 Keywords : lepton collider * electromagnetic calorimeter * embedded electronics * fake hits Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.207, year: 2011 http://arxiv.org/pdf/arXiv:1102.3454v2

  14. The VAK of vacuum fluctuation, Spontaneous self-organization and complexity theory interpretation of high energy particle physics and the mass spectrum

    International Nuclear Information System (INIS)

    El Naschie, M.S.

    2003-01-01

    The paper is a rather informal introduction to the concepts and results of the E-infinity Cantorian theory of quantum physics. The fundamental tools of complexity theory and non-linear dynamics (Hausdorff dimensions, fat fractals, etc.) are used to give what we think to be a new interpretation of high energy physics and to determine the corresponding mass-spectrum. Particular attention is paid to the role played by the VAK, KAM theorem, Arnold diffusion, Newhaus sinks and knot theory in determining the stability of an elementary 'particle-wave' which emerges in self-organizatory manner out of sizzling vacuum fluctuation

  15. Fragmentation into strange particles in high energy νp, νn, anti νp and anti νn interactions

    International Nuclear Information System (INIS)

    Allasia, D.; Cirio, R.; Gamba, D.; Ramello, L.; Riccati, L.; Romero, A.; Rustichelli, S.; Angelini, C.; Baldini, A.; Bertanza, L.; Casali, R.; Fantechi, R.; Flaminio, V.; Pazzi, R.; Bloch, M.; Bolognese, T.; Borg, A.; Faccini-Turluer, M.L.; Lippi, I.; Louedec, C.; Vignaud, D.; Capiluppi, P.; Derkaoui, J.; Giacomelli, G.; Mandrioli, G.; Margiotta, A.; Rossi, A.M.; Serra-Lugaresi, P.; Frodesen, A.G.; Jongejans, B.; Tenner, A.G.; Apeldoorn, G. van; Dam, P. van; Visser, C.; Wigmans, R.

    1985-01-01

    The fragmentation of the hardronic system into Λ, Σ(1385), K 0 and Ksup(*)(892) in deep-inelastic charged-current interactions of high energy neutrinos and antineutrinos with proton and neutron is analyzed. The results obtained for the production of these particles from the various initial states are compared with each other and with the predictions of the Lund fragmentation model. This comparison shows that a spectator diquark does not fragment as a whole in a fraction of the interactions. The role of the sea quarks in the baryon formation process is underlined. Strange vector and pseudoscalar mesons are likely to be produced at similar rates. (orig.)

  16. Theoretical Framework for Anomalous Heat Without High-Energy Particles from Deuteron Fusion in Deuterium-Transition Metal Systems

    International Nuclear Information System (INIS)

    Scott R. Chubb; Talbot A. Chubb

    2000-01-01

    In cold fusion, two conflicting intuitive pictures have caused confusion. A local picture, involving particle-particle interaction, has been dominant for most physicists. However, we suggest that a second, nonlocal, 'counter-intuitive' picture is more appropriate because it places greater emphasis on the behavior of matter distributions and their interaction with the associated environment. This picture is relevant in solids because when charged particles possess large DeBroglie wavelengths, they frequently interact coherently, in a wavelike fashion, in which momentum is conserved globally but not locally. These wavelike effects can become important in periodically ordered solids since they may lead to large momentum transfer from an isolated location to many locations at once. The local picture fails to incorporate these kinds of effects. How hydrogen (H) nuclei can become delocalized is illustrated by anomalies in the diffusivity and vibrational behavior of H in transition metals. Also, it is well-known that in many-body systems, discontinuities in the local momentum (wave function cusps) can explain how near-perfect overlap between charged particles can occur at close separation (which may explain how the Coulomb barrier can be circumvented). We explore implications of these effects on cold fusion

  17. High-energy detector

    Science.gov (United States)

    Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  18. High Energy $\

    CERN Multimedia

    2002-01-01

    This experiment is a high statistics exposure of BEBC filled with hydrogen to both @n and &bar.@n beams. The principal physics aims are : \\item a) The study of the production of charmed mesons and baryons using fully constrained events. \\end{enumerate} b) The study of neutral current interactions on the free proton. \\item c) Measurement of the cross-sections for production of exclusive final state N* and @D resonances. \\item d) Studies of hadronic final states in charged and neutral current reactions. \\item e) Measurement of inclusive charged current cross-sections and structure functions. \\end{enumerate}\\\\ \\\\ The neutrino flux is determined by monitoring the flux of muons in the neutrino shield. The Internal Picket Fence and External Muon Identifier of BEBC are essential parts of the experiment. High resolution cameras are used to search for visible decays of short-lived particles.

  19. The physics of radiation damage in particle detectors

    International Nuclear Information System (INIS)

    Van Lint, V.A.J.

    1987-01-01

    Intense high-energy particle beams cause damage to semiconductor detectors and signal-conditioning electronics by displacement and long-term ionization effects. While first-principles prediction of effects are not practical, the magnitude of each effect can be scaled approximately between particle energy and type by using an appropriate scaling parameter. (orig.)

  20. Improvement in the Design of Metal-Ceramic High Voltage Feedthroughs for use in High Energy Particle Accelerators

    CERN Document Server

    Weterings, W

    1999-01-01

    Large high-voltage devices operate in particle accelerators to steer charged particles in the desired direction. Solid and hollow rods of sintered alumina are used as insulating supports and high-voltage feedthroughs to power the electrodes of these electrostatic systems. The performance of the systems is often limited by voltage breakdown along the surface of the ceramic insulator (so-called surface flashover) or discharge between feedthrough and vacuum tank, which can lead to significant disruptions in terms of overall machine efficiency. Available results on the influence of the mechanical preparation, thermal history and particular cleaning techniques on commercially obtainable alumina samples have been studied in order to investigate possibilities for better preparation methodology of the insulating supports. Also the influence of the relative position of the feedthrough inside the vacuum tank on the high-voltage breakdown behaviour has been studied. This paper describes the theoretical and practical bac...