WorldWideScience

Sample records for alternative on-line cyclotron

  1. Alternative optical concept for electron cyclotron emission imaging

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J. X., E-mail: jsliu9@berkeley.edu [Department of Physics, University of California Berkeley, Berkeley, California 94720 (United States); Milbourne, T. [Department of Physics, College of William and Mary, Williamsburg, Virginia 23185 (United States); Bitter, M.; Delgado-Aparicio, L.; Dominguez, A.; Efthimion, P. C.; Hill, K. W.; Kramer, G. J.; Kung, C.; Pablant, N. A.; Tobias, B. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Kubota, S. [Department of Physics, University of California Los Angeles, Los Angeles, California 90095 (United States); Kasparek, W. [Department of Electrical Engineering, University of Stuttgart, Stuttgart (Germany); Lu, J. [Department of Physics, Chongqing University, Chongqing 400044 (China); Park, H. [Ulsan National Institute of Science and Technology, Ulsan 689-798 (Korea, Republic of)

    2014-11-15

    The implementation of advanced electron cyclotron emission imaging (ECEI) systems on tokamak experiments has revolutionized the diagnosis of magnetohydrodynamic (MHD) activities and improved our understanding of instabilities, which lead to disruptions. It is therefore desirable to have an ECEI system on the ITER tokamak. However, the large size of optical components in presently used ECEI systems have, up to now, precluded the implementation of an ECEI system on ITER. This paper describes a new optical ECEI concept that employs a single spherical mirror as the only optical component and exploits the astigmatism of such a mirror to produce an image with one-dimensional spatial resolution on the detector. Since this alternative approach would only require a thin slit as the viewing port to the plasma, it would make the implementation of an ECEI system on ITER feasible. The results obtained from proof-of-principle experiments with a 125 GHz microwave system are presented.

  2. On-Line Trajectory Retargeting for Alternate Landing Sites Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Barron Associates, Inc. proposes to develop a novel on-line trajectory optimization approach for Reusable Launch Vehicles (RLVs) under failure scenarios, targeting...

  3. On-line desalting of crude oil in the source region of a Fourier transform ion cyclotron resonance mass spectrometer.

    Science.gov (United States)

    Chanthamontri, C Ken; Stopford, Andrew P; Snowdon, Ryan W; Oldenburg, Thomas B P; Larter, Stephen R

    2014-08-01

    The presence of dissolved metal ions in waters associated with crude oils has many negative implications for the transport, processing, and refining of petroleum. In addition, mass spectrometric analysis of sodium containing crude oil samples suffers from ionization suppression, unwanted adduct formation, and an increase in the complexity of data analysis. Here, we describe a method for the reduction/elimination of these adverse effects by modification of the source region gas-inlet system of a 12 T Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. Several acids were examined as part of this study, with the most suitable for on-line desalting found to have both high vapor pressure and low pK(a); 12.1 M HCl showed the strongest desalting effect for crude oil samples with a sodium removal index (SRI) of 88%-100% ± 7% for the NaOS compound class. In comparison, a SRI of only 38% ± 9% was observed for a H₂O/toluene solution-phase extraction of oil 1. These results clearly demonstrate the increased efficacy of pseudo-vapor phase desalting with the additional advantages that initial sample solution conditions are preserved and no sample preparation is required prior to analysis.

  4. On-line measurements of proton beam current from a PET cyclotron using a thin aluminum foil

    Science.gov (United States)

    Ghithan, S.; do Carmo, S. J. C.; Ferreira Marques, R.; Fraga, F. A. F.; Simões, H.; Alves, F.; Crespo, P.

    2013-07-01

    The number of cyclotrons capable of accelerating protons to about 20 MeV is increasing throughout the world. Originally aiming at the production of positron emission tomography (PET) radionuclides, some of these facilities are equipped with several beam lines suitable for scientific research. Radiobiology, radiophysiology, and other dosimetric studies can be performed using these beam lines. In this work, we measured the Bragg peak of the protons from a PET cyclotron using a stacked target consisting of several aluminum foils interleaved with polyethylene sheets, readout by in-house made transimpedance electronics. The measured Bragg peak is consistent with simulations performed using the SRIM/TRIM simulation toolkit. Furthermore, we report on experimental results aiming at measuring proton beam currents down to 10 pA using a thin aluminum foil (20-μm-thick). The aluminum was chosen for this task because it is radiation hard, it has low density and low radiation activity, and finally because it is easily available at negligible cost. This method allows for calculating the dose delivered to a target during an irradiation with high efficiency, and with minimal proton energy loss and scattering.

  5. Cyclotron waves in plasma

    CERN Document Server

    Lominadze, D G

    2013-01-01

    Cyclotron Waves in Plasma is a four-chapter text that covers the basic physical concepts of the theory of cyclotron waves and cyclotron instabilities, brought about by the existence of steady or alternating plasma currents flowing perpendicular to the magnetic field.This book considers first a wide range of questions associated with the linear theory of cyclotron oscillations in equilibrium plasmas and in electron plasmas in metals and semiconductors. The next chapter deals with the parametric excitation of electron cyclotron oscillations in plasma in an alternating electric field. A chapter f

  6. This picture was taken in 1967 during the first test of the Isotope On-Line Separator (ISOLDE) installation at the 600 MeV CERN Synchro Cyclotron.

    CERN Multimedia

    1967-01-01

    When ISOLDE began operation, it was unique in the world. It used a new technique to overcome the problem of rapidly separating interesting atoms from the rest of the nuclear target. Through a combination of chemical and electromagnetic methods the different isotopes were separated and converted into an ion beam made of just one isotope. On-line production of radioactive nuclei, in this way, offered many new opportunities for physicists as it allowed them to perform previously impossible experiments on short-lived nuclei. ISOLDE has become one of CERN's major installations and it supports a broad scientific programme by providing beams to different experiments. The techniques developed at ISOLDE have opened up a new field of radioactive ion-beam accelerators, both at CERN and worldwide.

  7. Cyclotrons: 1978

    Energy Technology Data Exchange (ETDEWEB)

    Martin, J.A. (comp.)

    1978-01-01

    A compilation is presented of the experimental facilities of the world's cyclotrons including history and status, staff and operation, research staff, target facilities, magnet, acceleration system, vacuum system, characteristic beams, beam properties, and a plan view of the facility for each cyclotron. (GHT)

  8. Alfven cyclotron instability and ion cyclotron emission

    Energy Technology Data Exchange (ETDEWEB)

    Gorelenkov, N.N.; Cheng, C.Z.

    1995-07-01

    Two-dimensional solutions of compressional Alfven eigenmodes (CAE) are studied in the cold plasma approximation. For finite inverse aspect ratio tokamak plasmas the two-dimensional eigenmode envelope is localized at the low magnetic field side with the radial and poloidal localization on the order of a/{radical}m and a/(fourth root of m), respectively, where m is the dominant poloidal mode number. Charged fusion product driven Alfven Cyclotron Instability (ACI) of the compressional Alfven eigenmodes provides the explanation for the ion cyclotron emission (ICE) spectrum observed in tokamak experiments. The ACI is excited by fast charged fusion products via Doppler shifted cyclotron wave-particle resonances. The ion cyclotron and electron Landau dampings and fast particle instability drive are calculated perturbatively for deuterium-deuterium (DD) and deuterium-tritium (DT) plasmas. Near the plasma edge at the low field side the velocity distribution function of charged fusion products is localized in both pitch angle and velocity. The poloidal localization of the eigenmode enhances the ACI growth rates by a factor of {radical}m in comparison with the previous results without poloidal envelope. The thermal ion cyclotron damping determines that only modes with eigenfrequencies at multiples of the edge cyclotron frequency of the background ions can be easily excited and form an ICE spectrum similar to the experimental observations. Theoretical understanding is given for the results of TFTR DD and DT experiments with {upsilon}{sub {alpha}0}/{upsilon}{sub A} < 1 and JET experiments with {upsilon}{sub {alpha}0}/{upsilon}{sub A} > 1.

  9. Synchro-cyclotron

    CERN Multimedia

    1972-01-01

    The electromagnetic coil which forms the first section of the proton extraction channel in the improved synchro-cyclotron. The photograph shows the positioning gear and the current septum. An extraction efficiency above 50% is expected.

  10. The new cyclotrons

    CERN Multimedia

    Lawson, J D

    1966-01-01

    Article describing how valuable scientific work can still be carried out with the smaller energy cyclotrons such as those at the Radiochemical Centre, Amersham and the Atomic Energy Research Establishment, Harwell (2 pages).

  11. Cyclotron Institute Upgrade Project

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Henry [Texas A& M University; Yennello, Sherry [Texas A& M University; Tribble, Robert [Texas A& M University

    2014-08-26

    The Cyclotron Institute at Texas A&M University has upgraded its accelerator facilities to extend research capabilities with both stable and radioactive beams. The upgrade is divided into three major tasks: (1) re-commission the K-150 (88”) cyclotron, couple it to existing beam lines to provide intense stable beams into the K-500 experimental areas and use it as a driver to produce radioactive beams; (2) develop light ion and heavy ion guides for stopping radioactive ions created with the K-150 beams; and (3) transport 1+ ions from the ion guides into a charge-breeding electron-cyclotron-resonance ion source (CB-ECR) to produce highly-charged radioactive ions for acceleration in the K-500 cyclotron. When completed, the upgraded facility will provide high-quality re-accelerated secondary beams in a unique energy range in the world.

  12. Inflation and Cyclotron Motion

    CERN Document Server

    Greensite, Jeff

    2016-01-01

    We consider, in the context of a braneworld cosmology, the motion of the universe coupled to a four-form gauge field, with constant field strength, defined in higher dimensions. It is found, under rather general initial conditions, that in this situation there is a period of exponential inflation combined with cyclotron motion in the inflaton field space. The main effect of the cyclotron motion is that conditions on the flatness of the inflaton potential, which are typically necessary for exponential inflation, can be evaded. There are Landau levels associated with the four-form gauge field, and these correspond to quantum excitations of the inflaton field.

  13. Upgrading Synchro-cyclotron

    CERN Multimedia

    1974-01-01

    Final touches to the central region of SC2, the refurbished 600 MeV synchro-cyclotron, before the start of commissioning. Modifications included a new type of ion source at the centre. Protons were first accelerated in SC2 at full energy by October 1974. (See photo 7408042X)

  14. On-line moisture analysis

    CERN Document Server

    Cutmore, N G

    2002-01-01

    Measurement of the moisture content of iron ore has become a key issue for controlling moisture additions for dust suppression. In most cases moisture content is still determined by manual or automatic sampling of the ore stream, followed by conventional laboratory analysis by oven drying. Although this procedure enables the moisture content to be routinely monitored, it is too slow for control purposes. This has generated renewed interest in on-line techniques for the accurate and rapid measurement of moisture in iron ore on conveyors. Microwave transmission techniques have emerged over the past 40 years as the dominant technology for on-line measurement of moisture in bulk materials, including iron ores. Alternative technologies have their limitations. Infra-red analysers are used in a variety of process industries, but rely on the measurement of absorption by moisture in a very thin surface layer. Consequently such probes may be compromised by particle size effects and biased presentation of the bulk mater...

  15. Electron Cyclotron Emission Radiometer

    Science.gov (United States)

    Morales, Cristina

    2009-11-01

    There is much interest in studying plasmas that generate hot electrons. The goal of this project is to develop a wide band electron cyclotron radiometer to measure the non-Maxwellian rapid rises in electron temperature. These rapid increases in temperature will then be correlated to instabilities in the plasma. This project explores a type of noncontact temperature measurement. We will attempt to show the feasibility of electron cyclotron emissions to measure the Maryland Centrifugal Experiment's electron plasma temperature. The radiometer has been designed to have 100dB of gain and a sensitivity of 24mV/dB given by its logarithmic amplifier. If successful, this radiometer will be used as a diagnostic tool in later projects such as the proposed experiment studying magnetic reconnection using solar flux loops.

  16. Cyclotron Line Variability

    CERN Document Server

    Mihara, Tatehiro; Nagase, Fumiaki

    2014-01-01

    We systematically analyzed the spectra of X-ray binary pulsars observed with GINGA (Mihara 1995). A new model NPEX (Negative and Positive power-laws EXponential) was introduced t o represent the pulsar continuum. Combining the NPEX continuum with the CYAB factor (cyclotron resonance scattering model), we successfully fit the whole-band spectra of all the pulsars. A possible physical meaning of the NPEX model is the Comptonized spectra. By using the smooth and concave NPEX model, the cyclotron structures were detected from 12 pulsars, about a half of the 23 sources, including new discoveries from LMC X-4 and GS 1843+00. The magnetic fields were scattered in the range of $3\\times10^{11}$ - $5\\times10^{12}$ G. The distribution was shown for the first time, which is remarkably similar to that of radio pulsars with a peak at $2 \\times 10^{12}$ G. The double harmonic cyclotron structures of 4U 0115+63 in 1990 changed to a sin gle structure in 1991. The resonance energy also increased by 40 % as the luminosity decre...

  17. Cyclotrons and positron emitting radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, A.P.; Fowler, J.S.

    1984-01-01

    The state of the art of Positron Emission Tomography (PET) technology as related to cyclotron use and radiopharmaceutical production is reviewed. The paper discusses available small cyclotrons, the positron emitters which can be produced and the yields possible, target design, and radiopharmaceutical development and application. 97 refs., 12 tabs. (ACR)

  18. Spiral Inflector For Compact Cyclotron

    CERN Document Server

    Karamysheva, G A

    2004-01-01

    Compact cyclotron for explosives detection by nuclear resonance absorption of γ-rays in nitrogen is under development [1] Cyclotron will be equipped with the external ion source. The injection system consists of a double-drift beam bunching system, a spiral inflector, beam diagnostics, focusing and adjustment elements [2]. The spiral inflector for ion bending from axial to median plane is used. Computer model of spiral inflector for the Customs cyclotron is developed. 3D electrostatic field calculations of the designed inflector are performed. Calculated electric field map and magnetic field map of the cyclotron [3] are used for beam dynamic simulations. Numeric simulations are carried out for 500 particles using code for calculation of particle dynamics by integration of differential equations in Cartesian coordinate system written in MATLAB. Direct Coulomb particle-to-particle method is used to take into account space-charge effects.

  19. Ion Cyclotron Resonance Facility (ICR)

    Data.gov (United States)

    Federal Laboratory Consortium — his facility is charged with developing and exploiting the unique capabilities of Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry, and leads the...

  20. EC-5 fifth international workshop on electron cyclotron emission and electron cyclotron heating

    Energy Technology Data Exchange (ETDEWEB)

    Prater, R.; Lohr, J. [eds.

    1985-12-31

    This report contains papers on the following topics: electron cyclotron emission measurements; electron cyclotron emission theory; electron cyclotron heating; gyrotron development; and ECH systems and waveguide development. These paper have been indexed separately elsewhere. (LSP).

  1. Cyclotron resonant interactions in cosmic particle accelerators

    CERN Document Server

    Terasawa, T; 10.1007/s11214-012-9878-0

    2012-01-01

    A review is given for cyclotron resonant interactions in space plasmas. After giving a simple formulation for the test particle approach, illustrative examples for resonant interactions are given. It is shown that for obliquely propagating whistler waves, not only fundamental cyclotron resonance, but also other resonances, such as transit-time resonance, anomalous cyclotron resonance, higher-harmonic cyclotron resonance, and even subharmonic resonance can come into play. A few recent topics of cyclotron resonant interactions, such as electron injection in shocks, cyclotron resonant heating of solar wind heavy ions, and relativistic modifications, are also reviewed.

  2. Use of cyclotrons in medicine

    Energy Technology Data Exchange (ETDEWEB)

    Qaim, S.M. E-mail: s.m.qaim@fz-juelich.de

    2004-11-01

    Cyclotrons are versatile ion-accelerating machines which find many applications in medicine. In this short review their use in hadron therapy is briefly discussed. Proton therapy is gaining significance because of its capability to treat deep-lying tumours. A strong area of application of cyclotrons involves the production of short-lived neutron deficient radiotracers for use in emission tomography, especially positron emission tomography. This fast and quantitative in vivo diagnostic technique is being increasingly used in neurology, cardiology and oncology. Besides routine patient care, considerable interdisciplinary work on development of new positron emitters is under way. A short account of those efforts is given. The use of cyclotrons in the production of radionuclides for internal radiotherapy is also briefly described.

  3. CSIR cyclotron modified for radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    National Accelerator Centre (NAC) staff members will be making an important contribution to radiation therapy in South Africa when the Transvaal Department of Hospital Services starts treating certain types of cancer with fast neutrons, at the Pretoria Cyclotron on the CSIR campus. The fast neutrons will be utilized mainly to treat advanced cancers of the head and the neck. The project will develop along two lines. Firstly the Pretoria cyclotron must be modified and secondly satisfactory radiobiological data must be provided before patients may be treated. This radiobiological experiment heralds a new area for use of the cyclotron which has thus far been used mainly for basic nuclear research and the production of isotopes.

  4. MC-50 AVF cyclotron operation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Seok; Chai, Jong Seo; Bak, Seong Ki; Park, Chan Won; Jo, Young Ho; Hong, Seong Seok; Lee, Min Yong; Jang Ho Ha

    2000-01-01

    The first cyclotron in Korea, MC-50 cyclotron is used for neutron irradiation, radionuclide development, production and material and biomedical research. 50.5MeV and 35MeV proton beam have been extracted with 20-60{mu}A. A total of beam extraction time are 1095.7 hours. 206.5 hours are used for the developments and 663.8 hours are for radionuclide production and development and 225.4 hours for application researches. The shutdown days are 23 days. Fundamental data for failure decrement and efficient beam extraction were composed and maintenance technologies were developed.

  5. Status report on cyclotron operation

    CERN Document Server

    Kovács, P; Ander, I; Lakatos, T; Fenyvesi, A; Ditrói, F; Takács, S; Tarkanyi, F

    2003-01-01

    The operation of the cyclotron in 2002 was concentrated to 9 months; January, July and August were reserved for maintenance and holidays. The overall working time of the accelerator was 4084 hours, the breakdown periods amounted to 15 hours last year. In order to improve the circumstances of the irradiations, several following improvements were done. (R.P.)

  6. Meditsiin on-line

    Directory of Open Access Journals (Sweden)

    Mare Kõiva

    2008-08-01

    , polite and serious. A closer look at the construction and vocabulary of the doctor-patient communication act reveals that the most common features are formality and distancing – the partners are not equal in their sociopolitical standing. Inter-patient discussion groups are more varied in their style of communication and language use, ranging from informational notices to narratives and displays of emotion. A discussion concerning a visit to a folk healer is treated at more length. Interaction of this kind is a discussion that preserves the individual characteristics of many people in writing. Opinions are individualised, making the discussion similar to oral dialogue in which different strategies are used in reasoning. The posted messages reflect natural personal language use in forms ranging from informational notices to lengthy narratives. The general attitude is supportive and trusting towards official medicine and the personal reactions to social and situational events. A medical discussion board comprises a conditional group that does not form a network or community but engages in a dialogue to obtain and provide expert opinion. Users of patients’ discussion group and their narratives have a close connection to reality. The Internet offers the users new ways to share their practices and experiences and sometimes supports or even provides alternatives not available in offline reality. Such groups are based on information sharing and narratives and play an important role in maintaining emotional stability.

  7. Cyclotron Production of Technetium-99m

    Science.gov (United States)

    Gagnon, Katherine M.

    Technetium-99m (99mTc) has emerged as the most widely used radionuclide in medicine and is currently obtained from a 99Mo/ 99mTc generator system. At present, there are only a handful of ageing reactors worldwide capable of producing large quantities of the parent isotope, 99Mo, and owing to the ever growing shutdown periods for maintenance and repair of these ageing reactors, the reliable supply 99mTc has been compromised in recent years. With an interest in alternative strategies for producing this key medical isotope, this thesis focuses on several technical challenges related to the direct cyclotron production of 99mTc via the 100Mo(p,2n)99mTc reaction. In addition to evaluating the 100Mo(p,2n)99mTc and 100Mo(p,x)99Mo reactions, this work presented the first experimental evaluation of the 100Mo(p,2n) 99gTc excitation function in the range of 8-18 MeV. Thick target calculations suggested that large quantities of cyclotron-produced 99mTc may be possible. For example, a 6 hr irradiation at 500 μA with an energy window of 18→10 MeV is expected to yield 1.15 TBq of 99mTc. The level of coproduced 99gTc contaminant was found to be on par with the current 99Mo/99mTc generator standard eluted with a 24 hr frequency. Highly enriched 100Mo was required as the target material for 99mTc production and a process for recycling of this expensive material is presented. An 87% recovery yield is reported, including metallic target preparation, irradiation, 99mTc extraction, molybdate isolation, and finally hydrogen reduction to the metal. Further improvements are expected with additional optimization experiments. A method for forming structurally stable metallic molybdenum targets has also been developed. These targets are capable of withstanding more than a kilowatt of beam power and the reliable production and extraction of Curie quantities of 99mTc has been demonstrated. With the end-goal of using the cyclotron-produced 99mTc clinically, the quality of the cyclotron

  8. The development of cyclotron radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seung Dae; Chun, K. W.; Suh, Y. S.; Lee, J. D.; Ahn, S. H. and others

    1999-03-01

    The purpose of this project is to developthe radiopharmaceuticals and automatic synthetic unit for labelled compounds, and to establish mass production system of radiopharmaceuticals. These will contribute to the early diagnosis of the disease hard to cure. The contents of this project are as follows, the development of the radiopharmaceutical for imaging of cancer, the development of automatic synthesizer for the synthesis of radio-pharmaceuticals, the development of hormone derivatives labelled with {sup 12}'3I, the development of the radiopharmaceuticals for therapy of cancer labelled with cyclotron produced radionuclides, the development of radiopharmaceuticals for therapy of cancer labelled with cyclotron produced radionuclides, the development of radiopharmaceuticals for imaging of myocardial metabolism.

  9. Commercial compact cyclotrons in the 90`s

    Energy Technology Data Exchange (ETDEWEB)

    Milton, B.F.

    1995-09-01

    Cyclotrons continue to be efficient accelerators for radio-isotope production. In recent years, developments in the accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicate a strong future for commercial cyclotrons. In this paper the authors will survey recent developments in the areas of cyclotron technology, as they relate to the new generation of commercial cyclotrons. Design criteria for the different types of commercial cyclotrons will be presented, with reference to those demands that differ from those in a research oriented cyclotron project. The authors also discuss the possibility of systems designed for higher energies and capable of extracted beam currents of up to 2.0 mA.

  10. Method and apparatus for ion cyclotron spectrometry

    Science.gov (United States)

    Dahl, David A [Idaho Falls, ID; Scott, Jill R [Idaho Falls, ID; McJunkin, Timothy R [Idaho Falls, ID

    2010-08-17

    An ion cyclotron spectrometer may include a vacuum chamber that extends at least along a z-axis and means for producing a magnetic field within the vacuum chamber so that a magnetic field vector is generally parallel to the z-axis. The ion cyclotron spectrometer may also include means for producing a trapping electric field within the vacuum chamber that includes at least a first section that induces a first magnetron effect that increases a cyclotron frequency of an ion and at least a second section that induces a second magnetron effect that decreases the cyclotron frequency of an ion. The cyclotron frequency changes induced by the first and second magnetron effects substantially cancel one another so that an ion traversing the at least first and second sections will experience no net change in cyclotron frequency.

  11. The ISOLDE on-line isotope separator at the 600 MeV Synchro-Cyclotron

    CERN Multimedia

    CERN PhotoLab

    1973-01-01

    Is at present being thoroughly modified and improved, in order to allow for the increased proton beam intensities, resulting from the SC improvement programme. This photograph, taken before the dismantinling of the facility in June 1973, shows the separator analysing magnet (centre background), the collector chamber of the mass-separated ion.

  12. CERN Video News on line

    CERN Document Server

    2003-01-01

    The latest CERN video news is on line. In this issue : an interview with the Director General and reports on the new home for the DELPHI barrel and the CERN firemen's spectacular training programme. There's also a vintage video news clip from 1954. See: www.cern.ch/video or Bulletin web page

  13. Cyclotron Line Measurements with INTEGRAL

    Science.gov (United States)

    Pottschmidt, K.; Kreykenbohm, I.; Caballero, I.; Fritz, S.; Schoenherr, G.; Kretschmar, P.; Wilms, J.; McBride, V. A.; Suchy, S.; Rothschild, R. E.

    2008-01-01

    Due to its broadband energy coverage, INTEGRAL has made important contributions to observing and interpreting cyclotron lines, which are present in the 10-100 keV range of a sample of accreting pulsars. In these systems photons with energies fulfilling the resonance condition inelastically Compton scatter off electrons quantized in the accretion column above the neutron star's magnetic pole(s). This process gives rise to the broad, absorption-like lines or 'cyclotron resonant scattering features' (CRSF). The observed lines allow to directly measure the B-fields of these sources, resulting in values of a few times 1E12G. In this overview I will present recent highlights regarding CRSF observations as well as discuss current ideas and models for the physical conditions in the accretion column. Among the former are the stability of the spectrum of Vela X-1 during giant flares in 2003, the observation of three cyclotron lines during the 2004 outburst of V0332+53, the confirmation of the fundamental line at approximately 45 keV during a 2005 normal outburst of A0535-26, and the simultaneous detection of the two lines in the dipping source 4U 1907+09 (for which also a torque reversal was detected for the first time). Through these and other observations it has become increasingly apparent that two types of observations can potentially be used to constrain the accretion column geometry: the determination of energy ratios for multiple harmonic lines (only two sources with greater than 2 lines are known), was well as the evolution of the fundamental line centroid, which, for different sources, may or may not be correlated with flux. Furthermore, first steps have been taken away from the usual phenomenological description of the lines, towards a physical approach based on self-consistent CRSF modeling. Initial applications are presented.

  14. Ion cyclotron waves at Titan

    Science.gov (United States)

    Russell, C. T.; Wei, H. Y.; Cowee, M. M.; Neubauer, F. M.; Dougherty, M. K.

    2016-03-01

    During the interaction of Titan's thick atmosphere with the ambient plasma, it was expected that ion cyclotron waves would be generated by the free energy of the highly anisotropic velocity distribution of the freshly ionized atmospheric particles created in the interaction. However, ion cyclotron waves are rarely observed near Titan, due to the long growth times of waves associated with the major ion species from Titan's ionosphere, such as CH4+ and N2+. In the over 100 Titan flybys obtained by Cassini to date, there are only two wave events, for just a few minutes during T63 flyby and for tens of minutes during T98 flyby. These waves occur near the gyrofrequencies of proton and singly ionized molecular hydrogen. They are left-handed, elliptically polarized, and propagate nearly parallel to the field lines. Hybrid simulations are performed to understand the wave growth under various conditions in the Titan environment. The simulations using the plasma and field conditions during T63 show that pickup protons with densities ranging from 0.01 cm-3 to 0.02 cm-3 and singly ionized molecular hydrogens with densities ranging from 0.015 cm-3 to 0.25 cm-3 can drive ion cyclotron waves with amplitudes of ~0.02 nT and of ~0.04 nT within appropriate growth times at Titan, respectively. Since the T98 waves were seen farther upstream than the T63 waves, it is possible that the instability was stronger and grew faster on T98 than T63.

  15. Superconducting cyclotrons at Michigan State University

    Science.gov (United States)

    Blosser, H. G.

    1987-04-01

    This paper describes the status of the three superconducting cyclotrons which are in operation or under construction at the National Superconducting Cyclotron Laboratory. The oldest of these, the K500, has been in operation since September 1982 supporting a national user program in heavy ion nuclear physics. A second large research cyclotron, the K800, is now nearing completion. This cyclotron will accelerate lighter heavy ions to 200 MeV/nuc and heavier particles up to energies given by 1200 Q2/ A MeV/nucleon. The magnet for this cyclotron came into operation in May 1984 and has performed smoothly and reliably in three extended operating periods. At present, K800 construction activity centers on fabrication and installation of the rf system, the extraction system, and the ECR injection line. The third NSCL superconducting cyclotron is a smaller 50 MeV deuteron cyclotron to be used for neutron therapy in the radiation oncology center of a major Detroit hospital (Harper Hospital). Design features of this small, application oriented, cyclotron are described in some detail.

  16. Developing the smallest possible medical cyclotron

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    Imagine a portable medical cyclotron operated in a conventional radioactive facility at a hospital. Imagine a nurse or technician switching it on and producing isotopes at the patient’s bedside. Sounds like science fiction? Think again.   CERN has teamed up with Spain’s national scientific research centre (CIEMAT) to develop an avant-garde cyclotron to be used for Positron Emission Tomography (PET). “We plan to make a cyclotron that doesn't need an insulated building or ‘vault’: a cyclotron small enough to fit inside a hospital lift,” explains Jose Manuel Perez, who is leading the CIEMAT/CERN collaboration. “It will be the smallest possible medical cyclotron for single patient dose production and will dramatically reduce costs for hospitals.” While PET technology has transformed imaging techniques, many of its medical benefits have remained confined to highly specialised hospitals. “Studies have foun...

  17. Cyclotron-based effects on plant gravitropism

    Science.gov (United States)

    Kordyum, E.; Sobol, M.; Kalinina, Ia.; Bogatina, N.; Kondrachuk, A.

    Primary roots exhibit positive gravitropism and grow in the direction of the gravitational vector, while shoots respond negatively and grow opposite to the gravitational vector. We first demonstrated that the use of a weak combined magnetic field (CMF), which is comprised of a permanent magnetic field and an alternating magnetic field with the frequency resonance of the cyclotron frequency of calcium ions, can change root gravitropism from a positive direction to negative direction. Two-day-old cress seedlings were gravistimulated in a chamber that was placed into a μ-metal shield where this CMF was created. Using this "new model" of a root gravitropic response, we have studied some of its components including the movement of amyloplasts-statoliths in root cap statocytes and the distribution of Ca 2+ ions in the distal elongation zone during gravistimulation. Unlike results from the control, amyloplasts did not sediment in the distal part of a statocyte, and more Ca 2+ accumulation was observed in the upper side of a gravistimulated root for seedlings treated with the CMF. For plants treated with the CMF, it appears that a root gravitropic reaction occurs by a normal physiological process resulting in root bending although in the opposite direction. These results support the hypothesis that both the amyloplasts in the root cap statocytes and calcium are important signaling components in plant gravitropism.

  18. Injection and extraction for cyclotrons

    CERN Document Server

    Kleeven, W

    2006-01-01

    The main design goals for beam injection are explained and special problems related to a central region with internal ion source are considered. The principle of a PIG source is addressed. The issue of vertical focusing in the cyclotron centre is briefly discussed. Several examples of numerical simulations are given. Different ways of (axial) injection are briefly outlined. A proposal for a magnetostatic axial inflector is given. Different solutions for beam extraction are treated. These include the internal target, extraction by stripping, resonant extraction using a deflector and self-extraction. The different ways of creating a turn-separation are explained. The purpose of different types of extraction devices such as harmonic coils, deflectors and gradient corrector channels are outlined. Several illustrations are given in the form of photographs and drawings.

  19. Cyclotron resonance absorption in ionospheric plasma

    Science.gov (United States)

    Villalon, Elena

    1991-04-01

    The mode conversion of ordinary polarized electromagnetic waves into electrostatic cyclotron waves in the inhomogeneous ionospheric plasma is investigated. Near resonance the warm plasma dispersion relation is a function of the angle theta between the geomagnetic field and the density gradient and of the wave frequency omega, which lies between the electron cyclotron frequency and its doubling. The differential equations describing the electric field amplitudes near the plasma resonance are studied, including damping at the second gyroharmonic. The energy transmission coefficients and power absorbed by the cyclotron waves are calculated. The vertical penetration of the plasma wave amplitudes is estimated using a WKB analysis of the wave equation.

  20. The Leuven isotope separator on-line laser ion source

    CERN Document Server

    Kudryavtsev, Y; Franchoo, S; Huyse, M; Gentens, J; Kruglov, K; Müller, W F; Prasad, N V S; Raabe, R; Reusen, I; Van den Bergh, P; Van Duppen, P; Van Roosbroeck, J; Vermeeren, L; Weissman, L

    2002-01-01

    An element-selective laser ion source has been used to produce beams of exotic radioactive nuclei and to study their decay properties. The operational principle of the ion source is based on selective resonant laser ionization of nuclear reaction products thermalized and neutralized in a noble gas at high pressure. The ion source has been installed at the Leuven Isotope Separator On-Line (LISOL), which is coupled on-line to the cyclotron accelerator at Louvain-la-Neuve. sup 5 sup 4 sup , sup 5 sup 5 Ni and sup 5 sup 4 sup , sup 5 sup 5 Co isotopes were produced in light-ion-induced fusion reactions. Exotic nickel, cobalt and copper nuclei were produced in proton-induced fission of sup 2 sup 3 sup 8 U. The b decay of the sup 6 sup 8 sup - sup 7 sup 4 Ni, sup 6 sup 7 sup - sup 7 sup 0 Co, sup 7 sup 0 sup - sup 7 sup 5 Cu and sup 1 sup 1 sup 0 sup - sup 1 sup 1 sup 4 Rh isotopes has been studied by means of beta-gamma and gamma-gamma spectroscopy. Recently, the laser ion source has been used to produce neutron-d...

  1. PHENIX on-line systems

    Energy Technology Data Exchange (ETDEWEB)

    Adler, S.S.; Allen, M.; Alley, G.; Amirikas, R.; Arai, Y.; Awes, T.C.; Barish, K.N.; Barta, F.; Batsouli, S.; Belikov, S.; Bennett, M.J.; Bobrek, M.; Boissevain, J.G.; Boose, S.; Britton, C.; Britton, L.; Bryan, W.L.; Cafferty, M.M.; Carey, T.A.; Chang, W.C.; Chi, C.Y.; Chiu, M.; Cianciolo, V.; Cole, B.A.; Constantin, P.; Cook, K.C.; Cunitz, H.; Desmond, E.J.; Ebisu, K.; Efremenko, Y.V.; El Chenawi, K.; Emery, M.S.; Engo, D.; Ericson, N.; Fields, D.E.; Frank, S.; Frantz, J.E.; Franz, A.; Frawley, A.D.; Fried, J.; Gannon, J.; Gee, T.F.; Gentry, R.; Giannotti, P.; Gustafsson, H.-A.; Haggerty, J.S.; Hahn, S.; Halliwell, J.; Hamagaki, H.; Hansen, A.G.; Hara, H.; Harder, J.; He, X.; Heistermann, F.; Hemmick, T.K.; Hibino, M.; Hill, J.C. E-mail: jhill@iastate.edu; Homma, K.; Jacak, B.V.; Jagadish, U.; Jia, J.; Kajihara, F.; Kametani, S.; Kamyshkov, Y.; Kandasamy, A.; Kang, J.H.; Kapustinsky, J.; Katou, K.; Kelley, M.A.; Kelly, S.; Kikuchi, J.; Kim, S.Y.; Kim, Y.G.; Kistenev, E.; Kotchetkov, D.; Kurita, K.; Lajoie, J.G.; Lenz, M.; Lenz, W.; Li, X.H.; Lin, S.; Liu, M.X.; Markacs, S.; Matathias, F.; Matsumoto, T.; Mead, J.; Mischke, R.E.; Mishra, G.C.; Moore, A.; Muniruzzamann, M.; Musrock, M.; Nagle, J.L.; Nandi, B.K.; Newby, J.; Nystrand, J.; O' Brien, E.; O' Connor, P.; Ohnishi, H.; Oskarsson, A.; Osterman, L.; Oyama, K.; Paffrath, L.; Pancake, C.E.; Pantuev, V.S.; Petridis, A.N.; Pisani, R.P.; Plagge, T.; Plasil, F.; Purschke, M.L.; Rankowitz, S.; Rao, R.; Rau, M.; Read, K.F.; Ryu, S.S.; Sakaguchi, T.; Sato, H.D.; Seto, R.; Shiina, T.; Silvermyr, D.; Simon-Gillo, J.; Simpson, M.; Sippach, W.; Skank, H.D.; Skutnik, S.; Sleege, G.A.; Smith, G.D.; Smith, M.; Stankus, P.W.; Steinberg, P.; Sugitate, T.; Sullivan, J.P.; Taketani, A.; Tamai, M.; Tanaka, Y.; Thomas, W.D.; Todd, R.; Toldo, F.; Turner, G.; Ushiroda, T.; Velkovska, J.; Hecke, H.W. van; Lith, M. van; Villatte, L.; Achen, W. von; Walker, J.W.; Wang, H.Q.; White, S.N.; Wintenberg, A.L.; Witzig, C.; Wood, L.[and others

    2003-03-01

    The PHENIX On-Line system takes signals from the Front End Modules (FEM) on each detector subsystem for the purpose of generating events for physics analysis. Processing of event data begins when the Data Collection Modules (DCM) receive data via fiber-optic links from the FEMs. The DCMs format and zero suppress the data and generate data packets. These packets go to the Event Builders (EvB) that assemble the events in final form. The Level-1 trigger (LVL1) generates a decision for each beam crossing and eliminates uninteresting events. The FEMs carry out all detector processing of the data so that it is delivered to the DCMs using a standard format. The FEMs also provide buffering for LVL1 trigger processing and DCM data collection. This is carried out using an architecture that is pipelined and deadtimeless. All of this is controlled by the Master Timing System (MTS) that distributes the RHIC clocks. A Level-2 trigger (LVL2) gives additional discrimination. A description of the components and operation of the PHENIX On-Line system is given and the solution to a number of electronic infrastructure problems are discussed.

  2. On-Line Forecasting Capabilities: Futurscan and Its Alternatives.

    Science.gov (United States)

    Gerjuoy, Herbert G.; Owen, T. Gerald

    This paper provides an overview of the field of online information retrieval systems whose databases are programmed to predict future events. These systems rely on data of past events and use mathematical techniques such as regression analysis and statistical probability to provide forecast data. The history of these systems is traced through the…

  3. Electron cyclotron heating and current drive

    NARCIS (Netherlands)

    Westerhof, E.

    1996-01-01

    Plasma heating and non-inductive current drive by waves in the electron cyclotron range of frequencies are reviewed. Both theoretical aspects concerning wave properties, heating and current drive mechanisms, as well as the major experimental results are summarized.

  4. Method and apparatuses for ion cyclotron spectrometry

    Science.gov (United States)

    Dahl, David A [Idaho Falls, ID; Scott, Jill R [Idaho Falls, ID; McJunkin, Timothy R [Idaho Falls, ID

    2012-03-06

    An ion cyclotron spectrometer may include a vacuum chamber that extends at least along a z-axis and means for producing a magnetic field within the vacuum chamber so that a magnetic field vector is generally parallel to the z-axis. The ion cyclotron spectrometer may also include means for producing a trapping electric field within the vacuum chamber. The trapping electric field may comprise a field potential that, when taken in cross-section along the z-axis, includes at least one section that is concave down and at least one section that is concave up so that ions traversing the field potential experience a net magnetron effect on a cyclotron frequency of the ions that is substantially equal to zero. Other apparatuses and a method for performing ion cyclotron spectrometry are also disclosed herein.

  5. Building 211 cyclotron characterization survey report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-30

    The Building 211 Cyclotron Characterization Survey includes an assessment of the radioactive and chemical inventory of materials stored within the facility; an evaluation of the relative distribution of accelerator-produced activation products within various cyclotron components and adjacent structures; measurement of the radiation fields throughout the facility; measurement and assessment of internal and external radioactive surface contamination on various equipment, facility structures, and air-handling systems; and an assessment of lead (Pb) paint and asbestos hazards within the facility.

  6. Shielding Design for a Medical Cyclotron

    Institute of Scientific and Technical Information of China (English)

    WANG; Feng; SONG; Guo-fang; GUAN; Feng-ping; LV; Yin-long; ZHANG; Xing-zhi

    2012-01-01

    <正>A 10 MeV 100 μA medical cyclotron is constructed at CIAE which is used in the production of FDG. The energy of the cyclotron can reach 14 MeV by adjusting the magnetic field and RF system parameters, and the shielding design is in accordance with the 14 MeV beam energy. In this shielding design only neutron is considered, and the neutron source is produced by proton

  7. Progress of General Test Stand for Intensive Beam Cyclotron

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>The general test stand for intensive beam cyclotron is one of the preliminary tasks of BRIF project at CIAE. The test stand, which actually is a small compact cyclotron with designed energy of 10 MeV,

  8. Cyclotron resonance absorption in ionospheric plasma

    Energy Technology Data Exchange (ETDEWEB)

    Villalon, E. (Northeastern Univ., Boston, MA (USA) Geophysics Lab., Hanscom AFB, MA (USA))

    1991-04-01

    The mode conversion of ordinary polarized electromagnetic waves into electrostatic cyclotron waves in the inhomogeneous ionospheric plasma is investigated. Near resonance the warm plasma dispersion relation is a function of the angle {theta} between the geomagnetic field and the density gradient and of the wave frequency {omega}, where {Omega} {le} {omega} {le} 2{Omega} and {Omega} is the electron cyclotron frequency. The differential equations describing the electric field amplitudes near the plasma resonance are studied, including damping at the second gyroharmonic. For certain values of {omega} and {theta} (e.g., {theta} < 45{degree}, {omega} {approximately} 2{Omega}) the wave equations reduce to the parabolic cylinder equation. The energy transmission coefficients and power absorbed by the cyclotron waves are calculated. The vertical penetration of the plasma wave amplitudes is iestimated using a WKB analysis of the wave equation.

  9. Improving cancer treatment with cyclotron produced radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Larson, S.M. Finn, R.D.

    1992-08-04

    This report describes the author's continuing long term goal of promoting nuclear medicine applications by improving the scientific basis for tumor diagnosis treatment and treatment follow-up based on the use of cyclotron produced radiotracers in oncology. The program has 3 interactive components: Radiochemistry /Cyclotron; Pharmacology; and Immunology. An essential strategy is as follows: novel radionuclides and radiotracers developed in the Radiochemistry/Cyclotron section under the DOE grant during the 1989--1992 grant period, will be employed in the Pharmacology and Immunology sections of the DOE grant during the 1992--1995 grant period. The development of novel radionuclides and tracers is of course useful in and of itself, but their utility is greatly enhanced by the interaction with the immunology and pharmacology components of the program.

  10. A line-of-sight electron cyclotron emission receiver for electron cyclotron resonance heating feedback control of tearing modes

    DEFF Research Database (Denmark)

    Oosterbeek, J.W.; Bürger, A.; Westerhof, E.;

    2008-01-01

    An electron cyclotron emission (ECE) receiver inside the electron cyclotron resonance heating (ECRH) transmission line has been brought into operation. The ECE is extracted by placing a quartz plate acting as a Fabry-Perot interferometer under an angle inside the electron cyclotron wave (ECW) beam...

  11. The irradiation facility at the AGOR cyclotron

    NARCIS (Netherlands)

    Brandenburg, Sytze; Ostendorf, Reint; Hofstee, Mariet; Kiewiet, Harry; Beijers, Hans

    2007-01-01

    The KVI is conducting radiobiology research using protons up to 190 MeV from the superconducting AGOR cyclotron in collaboration with the University Medical Center Groningen (UMCG) since 1998. Using the same set-up, we have started irradiations for radiation hardness studies of detectors and compone

  12. Imaging Cyclotron Orbits of Electrons in Graphene.

    Science.gov (United States)

    Bhandari, Sagar; Lee, Gil-Ho; Klales, Anna; Watanabe, Kenji; Taniguchi, Takashi; Heller, Eric; Kim, Philip; Westervelt, Robert M

    2016-03-09

    Electrons in graphene can travel for several microns without scattering at low temperatures, and their motion becomes ballistic, following classical trajectories. When a magnetic field B is applied perpendicular to the plane, electrons follow cyclotron orbits. Magnetic focusing occurs when electrons injected from one narrow contact focus onto a second contact located an integer number of cyclotron diameters away. By tuning the magnetic field B and electron density n in the graphene layer, we observe magnetic focusing peaks. We use a cooled scanning gate microscope to image cyclotron trajectories in graphene at 4.2 K. The tip creates a local change in density that casts a shadow by deflecting electrons flowing nearby; an image of flow can be obtained by measuring the transmission between contacts as the tip is raster scanned across the sample. On the first magnetic focusing peak, we image a cyclotron orbit that extends from one contact to the other. In addition, we study the geometry of orbits deflected into the second point contact by the tip.

  13. Cyclotron-based neutron source for BNCT

    Science.gov (United States)

    Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Ogasawara, T.; Fujita, K.; Tanaka, H.; Sakurai, Y.; Maruhashi, A.

    2013-04-01

    Kyoto University Research Reactor Institute (KURRI) and Sumitomo Heavy Industries, Ltd. (SHI) have developed a cyclotron-based neutron source for Boron Neutron Capture Therapy (BNCT). It was installed at KURRI in Osaka prefecture. The neutron source consists of a proton cyclotron named HM-30, a beam transport system and an irradiation & treatment system. In the cyclotron, H- ions are accelerated and extracted as 30 MeV proton beams of 1 mA. The proton beams is transported to the neutron production target made by a beryllium plate. Emitted neutrons are moderated by lead, iron, aluminum and calcium fluoride. The aperture diameter of neutron collimator is in the range from 100 mm to 250 mm. The peak neutron flux in the water phantom is 1.8×109 neutrons/cm2/sec at 20 mm from the surface at 1 mA proton beam. The neutron source have been stably operated for 3 years with 30 kW proton beam. Various pre-clinical tests including animal tests have been done by using the cyclotron-based neutron source with 10B-p-Borono-phenylalanine. Clinical trials of malignant brain tumors will be started in this year.

  14. Cyclotron-based neutron source for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Ogasawara, T.; Fujita, K. [Sumitomo Heavy Industries, Ltd (Japan); Tanaka, H.; Sakurai, Y.; Maruhashi, A. [Kyoto University Research Reactor Institute (Japan)

    2013-04-19

    Kyoto University Research Reactor Institute (KURRI) and Sumitomo Heavy Industries, Ltd. (SHI) have developed a cyclotron-based neutron source for Boron Neutron Capture Therapy (BNCT). It was installed at KURRI in Osaka prefecture. The neutron source consists of a proton cyclotron named HM-30, a beam transport system and an irradiation and treatment system. In the cyclotron, H- ions are accelerated and extracted as 30 MeV proton beams of 1 mA. The proton beams is transported to the neutron production target made by a beryllium plate. Emitted neutrons are moderated by lead, iron, aluminum and calcium fluoride. The aperture diameter of neutron collimator is in the range from 100 mm to 250 mm. The peak neutron flux in the water phantom is 1.8 Multiplication-Sign 109 neutrons/cm{sup 2}/sec at 20 mm from the surface at 1 mA proton beam. The neutron source have been stably operated for 3 years with 30 kW proton beam. Various pre-clinical tests including animal tests have been done by using the cyclotron-based neutron source with {sup 10}B-p-Borono-phenylalanine. Clinical trials of malignant brain tumors will be started in this year.

  15. SC Cyclotron and RIB Facilities in Kolkata

    CERN Document Server

    Sinha, Bikash; Chakrabarti, Alok

    2005-01-01

    The superconducting cyclotron under construction at this Centre has bending limit (K-bend) of 520 and focusing limit (K-foc) of 160. It is being constructed, primarily, for nuclear physics experiments with heavy ion beams at intermediate energies. The 100-ton main magnet is currently in the commissioning phase with the main coil already at 4.2K temperature. Magnetic field measurements will be carried out over the next several months. All other systems of the cyclotron are in an advanced stage of fabrication or development. We plan to start assembly of the complete cyclotron around the end of 2005. In the phase-I of the project one beam line has been provided. Construction of three more beam lines and various experimental facilities for nuclear physics as well as irradiation experiments has also been funded and the work is well on its way. An ISOL type Radioactive Ion Beam (RIB) facility is being built with the existing K=130 room temperature cyclotron, VEC, as the primary beam source. In-beam RIB production a...

  16. <600> MeV synchro-cyclotron

    CERN Multimedia

    1971-01-01

    One of the 14 pancakes of the new magnet coils for the 600 MeV synchro-cyclotron which were wound and coated with epoxy resin on the CERN site. These new coils will replace the present ones which have been in use for more than 14 years but are now showing signs of deteriorations.

  17. Tokamak startup with electron cyclotron heating

    Energy Technology Data Exchange (ETDEWEB)

    Holly, D J; Prager, S C; Shepard, D A; Sprott, J C

    1980-04-01

    Experiments are described in which the startup voltage in a tokamak is reduced by approx. 60% by the use of a modest amount of electron cyclotron resonance heating power for preionization. A 50% reduction in volt-second requirement and impurity reflux are also observed.

  18. The war against on-line piracy

    OpenAIRE

    Harris, Julian

    2011-01-01

    A summary by Julian Harris, Deputy General Editor Amicus Curiae, of US attempts to control what it identifies as rogue Internet sites engaged in on-line piracy and opposition to such legislative moves.

  19. On-line generalized Steiner problem

    Energy Technology Data Exchange (ETDEWEB)

    Awerbuch, B.; Azar, Y.; Bartal, Y. [Tel Aviv Univ. (Israel)

    1996-12-31

    The Generalized Steiner Problem (GSP) is defined as follows. We are given a graph with non-negative weights and a set of pairs of vertices. The algorithm has to construct minimum weight subgraph such that the two nodes of each pair are connected by a path. We consider the on-line generalized Steiner problem, in which pairs of vertices arrive on-line and are needed to be connected immediately. We give a simple O(log{sup 2} n) competitive deterministic on-line algorithm. The previous best online algorithm (by Westbrook and Yan) was O({radical}n log n) competitive. We also consider the network connectivity leasing problem which is a generalization of the GSP. Here edges of the graph can be either bought or leased for different costs. We provide simple randomized O(log{sup 2} n) competitive algorithm based on the on-line generalized Steiner problem result.

  20. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry at the Cyclotron Frequency

    Science.gov (United States)

    Nagornov, Konstantin O.; Kozhinov, Anton N.; Tsybin, Yury O.

    2017-02-01

    The phenomenon of ion cyclotron resonance allows for determining mass-to-charge ratio, m/z, of an ensemble of ions by means of measurements of their cyclotron frequency, ω c . In Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), the ω c quantity is usually unavailable for direct measurements: the resonant state is located close to the reduced cyclotron frequency (ω+), whereas the ω c and the corresponding m/z values may be calculated via theoretical derivation from an experimental estimate of the ω+ quantity. Here, we describe an experimental observation of a new resonant state, which is located close to the ω c frequency and is established because of azimuthally-dependent trapping electric fields of the recently developed ICR cells with narrow aperture detection electrodes. We show that in mass spectra, peaks close to ω+ frequencies can be reduced to negligible levels relative to peaks close to ω c frequencies. Due to reduced errors with which the ω c quantity is obtained, the new resonance provides a means of cyclotron frequency measurements with precision greater than that achieved when ω+ frequency peaks are employed. The described phenomenon may be considered for a development into an FT-ICR MS technology with increased mass accuracy for applications in basic research, life, and environmental sciences.

  1. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry at the Cyclotron Frequency.

    Science.gov (United States)

    Nagornov, Konstantin O; Kozhinov, Anton N; Tsybin, Yury O

    2017-04-01

    The phenomenon of ion cyclotron resonance allows for determining mass-to-charge ratio, m/z, of an ensemble of ions by means of measurements of their cyclotron frequency, ω c . In Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), the ω c quantity is usually unavailable for direct measurements: the resonant state is located close to the reduced cyclotron frequency (ω+), whereas the ω c and the corresponding m/z values may be calculated via theoretical derivation from an experimental estimate of the ω+ quantity. Here, we describe an experimental observation of a new resonant state, which is located close to the ω c frequency and is established because of azimuthally-dependent trapping electric fields of the recently developed ICR cells with narrow aperture detection electrodes. We show that in mass spectra, peaks close to ω+ frequencies can be reduced to negligible levels relative to peaks close to ω c frequencies. Due to reduced errors with which the ω c quantity is obtained, the new resonance provides a means of cyclotron frequency measurements with precision greater than that achieved when ω+ frequency peaks are employed. The described phenomenon may be considered for a development into an FT-ICR MS technology with increased mass accuracy for applications in basic research, life, and environmental sciences. Graphical Abstract ᅟ.

  2. Cyclotrons as Drivers for Precision Neutrino Measurements

    Directory of Open Access Journals (Sweden)

    A. Adelmann

    2014-01-01

    Full Text Available As we enter the age of precision measurement in neutrino physics, improved flux sources are required. These must have a well defined flavor content with energies in ranges where backgrounds are low and cross-section knowledge is high. Very few sources of neutrinos can meet these requirements. However, pion/muon and isotope decay-at-rest sources qualify. The ideal drivers for decay-at-rest sources are cyclotron accelerators, which are compact and relatively inexpensive. This paper describes a scheme to produce decay-at-rest sources driven by such cyclotrons, developed within the DAEδALUS program. Examples of the value of the high precision beams for pursuing Beyond Standard Model interactions are reviewed. New results on a combined DAEδALUS—Hyper-K search for CP violation that achieve errors on the mixing matrix parameter of 4° to 12° are presented.

  3. Hybrid simulation of electron cyclotron resonance heating

    CERN Document Server

    Ropponen, T; Suominen, P; Koponen, T K; Kalvas, T; Koivisto, H

    2008-01-01

    Electron Cyclotron Resonance (ECR) heating is a fundamentally important aspect in understanding the physics of Electron Cyclotron Resonance Ion Sources (ECRIS). Absorption of the radio frequency (RF) microwave power by electron heating in the resonance zone depends on many parameters including frequency and electric field strength of the microwave, magnetic field structure and electron and ion density profiles. ECR absorption has been studied in the past by e.g. modelling electric field behaviour in the resonance zone and its near proximity. This paper introduces a new ECR heating code that implements damping of the microwave power in the vicinity of the resonance zone, utilizes electron density profiles and uses right hand circularly polarized (RHCP) electromagnetic waves to simulate electron heating in ECRIS plasma.

  4. TFTR Michelson interferometer electron cyclotron emission diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Stauffer, F.J.; Boyd, D.A.; Cutler, R.C.; McCarthy, M.P.

    1985-05-01

    In July 1984, a Fourier transform spectrometer employing a fast-scanning Michelson interferometer began operating on TFTR. This diagnostic system can measure the electron cyclotron emission spectrum 72 times per s with a time resolution of 11 ms and a spectral resolution of 3.6 GHz. The initial operating spectral range is 75--540 GHz, which is adequate for measuring the first three cyclotron harmonics at present TFTR magnetic field levels. The range can be extended easily to 75--1080 GHz in order to accommodate increases in toroidal magnetic field or to study superthermal ECE. The measured spectra are absolutely calibrated using a liquid nitrogen cooled blackbody reference source. The second harmonic feature of each spectrum is used to calculate the absolute electron temperature profile.

  5. ACSEPP On-Line Electronic Payment Protocol

    Institute of Scientific and Technical Information of China (English)

    WANG Shao-bin; ZHU Xian; HONG Fan

    2004-01-01

    With analyzing the existing on-line electronic payment protocols, this paper presents a new on-line electronic payment protocol named ACSEPP: Anonymous, Convenient and Secure Electronic Payment Protocol.Its aim is to design a practical electronic payment protocol which is both secure and convenient.Without using PKI_CA frame, it realized the anonymity of consumer and merchant, the convenient of handling, the low cost of maintenance and the security.

  6. On-Line Acquisitions by LOLITA

    Directory of Open Access Journals (Sweden)

    Frances G. Spigai

    1970-12-01

    Full Text Available The on-line acquisition program (LOLITA in use at the Oregon State University Library is described in terms of development costs, equipment requirements, and overall design philosophy. In particular, the record format and content of records in the on-order file, and the on-line processing of these records (input, search, correction, output using a cathode ray tube display terminal are detailed.

  7. Ion Cyclotron Heating on Proto-MPEX

    Science.gov (United States)

    Goulding, R. H.; Caughman, J. B. O.; Rapp, J.; Biewer, T. M.; Campbell, I. H.; Caneses, J. F.; Kafle, N.; Ray, H. B.; Showers, M. A.; Piotrowicz, P. A.

    2016-10-01

    Ion cyclotron heating will be used on Proto-MPEX (Prototype Material Plasma Exposure eXperiment) to increase heat flux to the target, to produce varying ion energies without substrate biasing, and to vary the extent of the magnetic pre-sheath for the case of a tilted target. A 25 cm long, 9 cm diameter dual half-turn helical ion cyclotron antenna has been installed in the device located at the magnetic field maximum. It couples power to ions via single pass damping of the slow wave at the fundamental resonance, and operates with ω 0.8ωci at the antenna location. It is designed to operate at power levels up to 30 kW, with a later 200 kW upgrade planned. Near term experiments include measuring RF loading at low power as a function of frequency and antenna gap. The plasma is generated by a helicon plasma source that has achieved ne > 5 ×1019m-3 operating with deuterium, as measured downstream from the ion cyclotron antenna location. Measurements will be compared with 1-D and 2-D models of RF coupling. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  8. Beam stripping extraction from the VINCY cyclotron

    Directory of Open Access Journals (Sweden)

    Ristić-Đurović Jasna L.

    2006-01-01

    Full Text Available The extraction system of a cyclotron guides an ion beam from a spiral acceleration orbit, through an extraction trajectory, into a high energy transport line. The two methods commonly used to direct an ion into the extraction path are deflection, by the electric field of an electrostatic deflector, and ion stripping, by a thin carbon foil. Compared to the electrostatic deflector system, the stripping extraction provides a fast and easy change of the extracted ion energy and is easier to manufacture operate, and maintain. However, the extraction trajectory and dynamics of an ion beam after stripping are highly dependant on the ion energy and specific charge. Thus, when a multipurpose machine such as the VINCY Cyclotron is concerned, it is far from easy to deliver a variety of ion beams into the same high energy transport line and at the same time preserve a reasonable compactness of the extraction system. The front side stripping extraction system of the VINCY Cyclotron provides high (~70 MeV and mid (~30 MeV energy protons, as well as a number of heavy ions in broad energy ranges. The back side stripping extraction system extracts low energy protons (~18 MeV and enables their simultaneous use with high energy protons at the front side of the machine.

  9. Transparency of Magnetized Plasma at Cyclotron Frequency

    Energy Technology Data Exchange (ETDEWEB)

    G. Shvets; J.S. Wurtele

    2002-03-14

    Electromagnetic radiation is strongly absorbed by a magnetized plasma if the radiation frequency equals the cyclotron frequency of plasma electrons. It is demonstrated that absorption can be completely canceled in the presence of a magnetostatic field of an undulator or a second radiation beam, resulting in plasma transparency at the cyclotron frequency. This effect is reminiscent of the electromagnetically induced transparency (EIT) of the three-level atomic systems, except that it occurs in a completely classical plasma. Unlike the atomic systems, where all the excited levels required for EIT exist in each atom, this classical EIT requires the excitation of the nonlocal plasma oscillation. The complexity of the plasma system results in an index of refraction at the cyclotron frequency that differs from unity. Lagrangian description was used to elucidate the physics and enable numerical simulation of the plasma transparency and control of group and phase velocity. This control naturally leads to applications for electromagnetic pulse compression in the plasma and electron/ion acceleration.

  10. Commercial compact cyclotrons in the 90's

    Energy Technology Data Exchange (ETDEWEB)

    Milton, B.F

    1995-09-01

    Cyclotrons continue to be efficient accelerators for radio-isotope production. In recent years, developments in the accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicate a strong future for commercial cyclotrons. In this paper we will survey recent developments in the areas of cyclotron technology, as they relate to the new generation of commercial cyclotrons. Design criteria for the different types of commercial cyclotrons will be presented, with reference to those demands that differ from those in a research oriented cyclotron project. We will also discuss the possibility of systems designed for higher energies and capable of extracted beam currents of up to 2.0 mA. (author)

  11. Nuclear physics with superconducting cyclotron at Kolkata: Scopes and possibilities

    Indian Academy of Sciences (India)

    Sailajananda Bhattacharya

    2010-08-01

    The K500 superconducting cyclotron at the Variable Energy Cyclotron Centre, Kolkata, India is getting ready to deliver its first accelerated ion beam for experiment. At the same time, the nuclear physics programme and related experimental facility development activities are taking shape. A general review of the nuclear physics research opportunities with the superconducting cyclotron and the present status of the development of different detector arrays and other experimental facilities will be presented.

  12. Potential of ion cyclotron resonance frequency current drive via fast waves in DEMO

    Science.gov (United States)

    Kazakov, Ye O.; Van Eester, D.; Wauters, T.; Lerche, E.; Ongena, J.

    2015-02-01

    For the continuous operation of future tokamak-reactors like DEMO, non-inductively driven toroidal plasma current is needed. Bootstrap current, due to the pressure gradient, and current driven by auxiliary heating systems are currently considered as the two main options. This paper addresses the current drive (CD) potential of the ion cyclotron resonance frequency (ICRF) heating system in DEMO-like plasmas. Fast wave CD scenarios are evaluated for both the standard midplane launch and an alternative case of exciting the waves from the top of the machine. Optimal ICRF frequencies and parallel wave numbers are identified to maximize the CD efficiency. Limitations of the high frequency ICRF CD operation are discussed. A simplified analytical method to estimate the fast wave CD efficiency is presented, complemented with the discussion of its dependencies on plasma parameters. The calculated CD efficiency for the ICRF system is shown to be similar to those for the negative neutral beam injection and electron cyclotron resonance heating.

  13. On line routing per mobile phone

    DEFF Research Database (Denmark)

    Bieding, Thomas; Görtz, Simon; Klose, Andreas

    2009-01-01

    . Additionally it is of utmost importance that the employed communication system is suitable integrated with the firm’s enterprise application system and business processes. On basis of a case study, we describe in this paper a system that is cheap and easy to implement due to the use of simple mobile phones......On-line routing is concerned with building vehicle routes in an ongoing fashion in such a way that customer requests arriving dynamically in time are efficiently and effectively served. An indispensable prerequisite for applying on-line routing methods is mobile communication technology...

  14. Educational On-Line Gaming Propensity

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana; Kirchner, Kathrin

    2014-01-01

    Educational on-line games are promising for new generations of students who are grown up digital. Th e new generations of students are technology savvy and spend lots of time on the web and on social networks. Based on an exploratory study, this article investigates the factors that infl uence...... students’ willingness to participate in serious games for teaching/learning. Th is study investigates the relationship between students’ behavior on Facebook, Facebook games, and their attitude toward educational on-line games. Th e results of the study reveal that the early adopters of educational games...

  15. Status of the Cyclotron Institute Upgrade Project

    Science.gov (United States)

    Melconian, Dan

    2016-09-01

    The Texas A&M University Re-accelerated EXotics (T-REX) project, an upgrade to the Cyclotron Institute, will provide high-quality re-accelerated secondary beams of a unique energy range and the ability to provide primary beams to two experiments concurrently. The upgrade is nearing completion of its three major tasks: re-commissioning of the existing K150 cyclotron; construction of light- and heavy-ion guide transport systems; and charge-boosting the K150 RIB for re-acceleration using the K500 cyclotron. The light-ion guide transport system will utilize the high intensity (>= 10 μ A) proton beam from the K150 to produce rare ions via fusion-evapouration reactions or proton-induced fission fragments. These ions will be transported to an ECR charge breeder prior to injection in the K500. The heavy-ion guide will use deep inelastic, transfer and fragmentation reactions using the up to 25 MeV/u primary beams from the K150. The products will be separated by a superconducting solenoid and collected in a large gas-catcher, after which a multi-RFQ system will transport the RIB to any of: the charge-breeder and K500; the TAMU Penning Trap beamline; or an MR-TOF for beam analysis. The status of the T-REX upgrade and an overview of its capabilities will be presented Supported by DOE Grant Number DE-FG03-93ER40773 and the Robert A. Welch Foundation Grant Number H-A-0098.

  16. Relativistic Cyclotron Instability in Anisotropic Plasmas

    Science.gov (United States)

    López, Rodrigo A.; Moya, Pablo S.; Navarro, Roberto E.; Araneda, Jaime A.; Muñoz, Víctor; Viñas, Adolfo F.; Alejandro Valdivia, J.

    2016-11-01

    A sufficiently large temperature anisotropy can sometimes drive various types of electromagnetic plasma micro-instabilities, which can play an important role in the dynamics of relativistic pair plasmas in space, astrophysics, and laboratory environments. Here, we provide a detailed description of the cyclotron instability of parallel propagating electromagnetic waves in relativistic pair plasmas on the basis of a relativistic anisotropic distribution function. Using plasma kinetic theory and particle-in-cell simulations, we study the influence of the relativistic temperature and the temperature anisotropy on the collective and noncollective modes of these plasmas. Growth rates and dispersion curves from the linear theory show a good agreement with simulations results.

  17. Electron cyclotron emission diagnostics on KSTAR tokamak.

    Science.gov (United States)

    Jeong, S H; Lee, K D; Kogi, Y; Kawahata, K; Nagayama, Y; Mase, A; Kwon, M

    2010-10-01

    A new electron cyclotron emission (ECE) diagnostics system was installed for the Second Korea Superconducting Tokamak Advanced Research (KSTAR) campaign. The new ECE system consists of an ECE collecting optics system, an overmode circular corrugated waveguide system, and 48 channel heterodyne radiometer with the frequency range of 110-162 GHz. During the 2 T operation of the KSTAR tokamak, the electron temperatures as well as its radial profiles at the high field side were measured and sawtooth phenomena were also observed. We also discuss the effect of a window on in situ calibration.

  18. Electron cyclotron emission diagnostics on KSTAR tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, S. H. [Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Daejeon 305-353 (Korea, Republic of); Lee, K. D.; Kwon, M. [National Fusion Research Institute, 113 Gwahangno, Daejeon 305-333 (Korea, Republic of); Kogi, Y. [Fukuoka Institute of Technology, Higashiku, Fukuoka 811-0295 (Japan); Kawahata, K.; Nagayama, Y. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Mase, A. [KASTEC, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan)

    2010-10-15

    A new electron cyclotron emission (ECE) diagnostics system was installed for the Second Korea Superconducting Tokamak Advanced Research (KSTAR) campaign. The new ECE system consists of an ECE collecting optics system, an overmode circular corrugated waveguide system, and 48 channel heterodyne radiometer with the frequency range of 110-162 GHz. During the 2 T operation of the KSTAR tokamak, the electron temperatures as well as its radial profiles at the high field side were measured and sawtooth phenomena were also observed. We also discuss the effect of a window on in situ calibration.

  19. Microwave Absorption in Electron Cyclotron Resonance Plasma

    Institute of Scientific and Technical Information of China (English)

    LIU Ming-Hai; HU Xi-Wei; WU Qin-Chong; YU Guo-Yang

    2000-01-01

    The microwave power absorption in electron cyclotron resonance plasma reactor was investigated with a twodimensional hybrid-code. Simulation results indicated that there are two typical power deposition profiles over the entire parameter region: (1) microwave power deposition peaks on the axis and decreases in radial direction,(2) microwave power deposition has its maximum at some radial position, i.e., a hollow distribution. The spatial distribution of electron temperature resembles always to the microwave power absorption profile. The dependence of plasma parameter on the gas pressure is discussed also.

  20. ON-LINE DOCUMENTS CONTENT MANAGEMENT

    Directory of Open Access Journals (Sweden)

    VASILESCU RAMONA VIOLETA

    2010-05-01

    Full Text Available This paper outlines the steps and technologies used in developing an on-line application server with many desktop clients, and with high power processing for a wide range of input documents to obtain searchable documents on the highest portability standards, PDF and PDF /A.

  1. Electron Cyclotron Resonance Heating of a High-Density Plasma

    DEFF Research Database (Denmark)

    Hansen, F. Ramskov

    1986-01-01

    Various schemes for electron cyclotron resonance heating of tokamak plasmas with the ratio of electron plasma frequency to electron cyclotron frequency, "»pe/^ce* larger than 1 on axis, are investigated. In particular, a mode conversion scheme is investigated using ordinary waves at the fundamental...

  2. The next generation of electron cyclotron emission imaging diagnostics (invited)

    NARCIS (Netherlands)

    Zhang, P.; Domier, C.W.; Liang, T.; Kong, X.; Tobias, B.; Shen, Z.; N C Luhmann Jr.,; Park, H.; Classen, I.G.J.; van de Pol, M.J.; Donne, A. J. H.; R. Jaspers,

    2008-01-01

    A 128 channel two-dimensional electron cyclotron emission imaging system collects time-resolved 16x8 images of T-e profiles and fluctuations on the TEXTOR tokamak. Electron cyclotron emission imaging (ECEI) is undergoing significant changes which promise to revolutionize and extend its capabilities

  3. A new generation of medical cyclotrons for the 90`s

    Energy Technology Data Exchange (ETDEWEB)

    Milton, B.F.

    1995-08-01

    Cyclotrons continue to be efficient accelerators for use in radio-isotope production. In recent years, developments in accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicates a strong future for commercial cyclotrons. In this paper the authors will survey recent developments in the areas of cyclotron technology as they relate to the new generation of commercial cyclotrons. Existing and potential markets for these cyclotrons will be presented. They will also discuss the possibility of systems capable of extracted energies up to 150 MeV and extracted beam currents of up to 2.0 mA.

  4. Cyclotron resonance effects on stochastic acceleration of light ionospheric ions

    Science.gov (United States)

    Singh, N.; Schunk, R. W.; Sojka, J. J.

    1982-01-01

    The production of energetic ions with conical pitch angle distributions along the auroral field lines is a subject of considerable current interest. There are several theoretical treatments showing the acceleration (heating) of the ions by ion cyclotron waves. The quasi-linear theory predicts no acceleration when the ions are nonresonant. In the present investigation, it is demonstrated that the cyclotron resonances are not crucial for the transverse acceleration of ions by ion cyclotron waves. It is found that transverse energization of ionospheric ions, such as He(+), He(++), O(++), and O(+), is possible by an Electrostatic Hydrogen Cyclotron (EHC) wave even in the absence of cyclotron resonance. The mechanism of acceleration is the nonresonant stochastic heating. However, when there are resonant ions both the total energy gain and the number of accelerated ions increase with increasing parallel wave number.

  5. Cyclotron and linac production of Ac-225.

    Science.gov (United States)

    Melville, Graeme; Allen, Barry J

    2009-04-01

    Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. The reduction of radium by photonuclear transmutation by bombarding Ra-226 with high-energy photons from a medical linear accelerator (linac) has been investigated. A linac dose of 2800 Gy produced about 2.4 MBq (64 microCi) of Ra-225, which decays to Ac-225 and can then be used for 'Targeted Alpha Therapy' (TAT) of cancer. This result, while consistent with theoretical calculations, is far too low to be of practical use unless much larger quantities of radium are irradiated. The increasing application of Ac-225 for cancer therapy indicates the potential need for its increased production and availability. This paper investigates the possibility of producing of Ac-225 in commercial quantities, which could potentially reduce obsolete radioactive material and displace the need for expensive importation of Ac-225 from the USA and Russia in the years ahead. Scaled up production of Ac-225 could theoretically be achieved by the use of a high current cyclotron or linac. Production specifications are determined for a linac in terms of current, pulse length and frequency, as well as an examination of other factors such as radiation issues and radionuclei separation. Yields are compared with those calculated for the Australian National Cyclotron in Sydney.

  6. Status of the NSCL Cyclotron Gas Stopper

    CERN Document Server

    Joshi, N; Brodeur, M; Morrissey, D J; Schwarz, S

    2016-01-01

    A gas-filled reverse cyclotron for the thermalisation of energetic beams is under construction at NSCL/MSU. Rare isotopes produced via projectile fragmentation after in-flight separation will be injected into the device and converted into low-energy beams through buffer gas interactions as they spiral towards the centre of the device. The extracted thermal beams will be used for low energy experiments such as precision mass measurements with traps or laser spectroscopy, and further transport for reacceleration. Detailed calculations have been performed to optimize the magnetic field design as well as the transport and stopping of ions inside the gas. An RF carpet will be used to transport the thermal ions to the axial extraction point. The calculations indicate that the cyclotron gas stopper will be much more efficient for the thermalisation of light and medium mass ions compared to linear gas cells. In this contribution we will discuss simulations of the overall performance and acceptance of machine, the bea...

  7. Roles of Fast-Cyclotron and Alfven-Cyclotron Waves for the Multi-Ion Solar Wind

    CERN Document Server

    Xiong, Ming

    2012-01-01

    Using linear Vlasov theory of plasma waves and quasi-linear theory of resonant wave-particle interaction, the dispersion relations and the electromagnetic field fluctuations of fast and Alfven waves are studied for a low-beta multi-ion plasma in the inner corona. Their probable roles in heating and accelerating the solar wind via Landau and cyclotron resonances are quantified. We assume that (1) low-frequency Alfven and fast waves have the same spectral shape and the same amplitude of power spectral density; (2) these waves eventually reach ion cyclotron frequencies due to a turbulence cascade; (3) kinetic wave-particle interaction powers the solar wind. The existence of alpha particles in a dominant proton/electron plasma can trigger linear mode conversion between oblique fast-whistler and hybrid alpha-proton cyclotron waves. The fast-cyclotron waves undergo both alpha and proton cyclotron resonances. The alpha cyclotron resonance in fast-cyclotron waves is much stronger than that in Alfven-cyclotron waves. ...

  8. Design of a superconducting beam transport channel and beam dynamics for a strong-focusing cyclotron

    Science.gov (United States)

    Badgley, Karie Elizabeth

    There is an increasing interest in high power proton accelerators for use as neutron and muon sources, accelerator driven systems (ADS) for nuclear waste transmutation, high energy physics, medical physics, nuclear physics, and medical isotope production. Accelerating high current beams has a number of challenges; including avoiding harmful resonance crossing, space charge effects and, specific to cyclotrons, sufficient turn separation at injection and extraction. The Accelerator Research Laboratory at Texas A&M University is developing a high-power strong-focusing cyclotron with two main technologies to overcome these challenges. The first is a superconducting RF cavity to provide the energy gain required for fully separated turns. The second is the use of superconducting beam transport channels within the sectors of the cyclotron to provide strong-focusing with alternating focusing and defocusing quadrupoles. A method has been developed to find the equilibrium spiral orbit through the cyclotron which maintains isochronicity. The isochronous spiral orbit was then used to perform full linear optics calculations. The strengths of the quadrupoles were adjusted to hold the horizontal and vertical betatron tunes constant per turn to avoid resonance crossing. Particle tracking was performed with a modified MAD-X-PTC code and Synergia to provide a framework for future space charge studies. Magnetic modeling was performed on a 2D cross section of the beam transport channel. The wire locations were adjusted to reduce the higher order multipoles and a good field region was obtained at 70% of the beam pipe aperture with multipoles less than 10-4 . The 2D model was also used to determine the required current density needed to produce the quadrupole gradients. MgB2 superconducting wire was chosen as it meets all the field and current requirements and can operate at a reduced cryogenic cost. A winding mandrel was also designed and fabricated which minimized the bend radius for

  9. New Trends in on-line Marketing

    OpenAIRE

    Palkovič, Lukáš

    2011-01-01

    This bachelor thesis deals with new trend of internet marketing, it focuses especially on viral marketing. The theoretical part charasterizes the process of viral campaigns, furthermore deals with the components and aspects of on-line environment. Another separated chapter presents social networks, their place in viral marketing and at last but not least the viral video making process. The practical part contains different analyses of specific viral campaigns. The next and equally the last pa...

  10. Electron cyclotron emission measurements at the stellarator TJ-K

    Energy Technology Data Exchange (ETDEWEB)

    Sichardt, Gabriel; Ramisch, Mirko [Institut fuer Grenzflaechenverfahrenstechnik und Plasmatechnologie, Universitaet Stuttgart (Germany); Koehn, Alf [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    2016-07-01

    Electron temperature (T{sub e}) measurements in the magnetised plasmas of the stellarator TJ-K are currently performed by means of Langmuir probes. The use of these probes is restricted to relatively low temperatures and the measurement of temperature profiles requires the acquisition of the local current-voltage characteristics which limits strongly the sampling rate. As an alternative, T{sub e} can be measured using the electron cyclotron emission (ECE) that is generated by the gyration of electrons in magnetised plasmas. Magnetic field gradients in the plasma lead to a spatial distribution of emission frequencies and thus the measured intensity at a given frequency can be related to its point of origin. The T{sub e} dependence of the intensity then leads to a temperature profile along the line of sight for Maxwellian velocity distributions. A diagnostic system for T{sub e} measurements using ECE is currently being set up at TJ-K. When non-thermal electrons are present the emission spectrum changes dramatically. Therefore, the ECE can also be used to investigate the contribution of fast electrons to previously observed toroidal net currents in TJ-K. Simulations are used to examine the role of electron drift orbits in generating these currents.

  11. Ion cyclotron resonance heating system on Aditya

    Indian Academy of Sciences (India)

    D Bora; Sunil Kumar; Raj Singh; S V Kulkarni; A Mukherjee; J P Singh; Raguraj Singh; S Dani; A Patel; Sai Kumar; V George; Y S S Srinivas; P Khilar; M Kushwah; P Shah; H M Jadav; Rajnish Kumar; S Gangopadhyay; H Machhar; B Kadia; K Parmar; A Bhardwaj; Suresh Adav; D Rathi; D S Bhattacharya

    2005-02-01

    An ion cyclotron resonance heating (ICRH) system has been designed, fabricated indigenously and commissioned on Tokamak Aditya. The system has been commissioned to operate between 20·0 and 47·0 MHz at a maximum power of 200 kW continuous wave (CW). Duration of 500 ms is sufficient for operation on Aditya, however, the same system feeds the final stage of the 1·5 MW ICRH system being prepared for the steady-state superconducting tokamak (SST-1) for a duration of 1000 s. Radio frequency (RF) power (225 kW) has been generated and successfully tested on a dummy load for 100s at 30·0 MHz. Lower powers have been coupled to Aditya in a breakdown experiment. We describe the system in detail in this work.

  12. Simulation of cyclotron resonant scattering features

    Directory of Open Access Journals (Sweden)

    Schwarm Fritz-Walter

    2014-01-01

    Full Text Available X-ray binary systems consisting of a mass donating optical star and a highly magnetized neutron star, under the right circumstances, show quantum mechanical absorption features in the observed spectra called cyclotron resonant scattering features (CRSFs. We have developed a simulation to model CRSFs using Monte Carlo methods. We calculate Green’s tables which can be used to imprint CRSFs to arbitrary X-ray continua. Our simulation keeps track of scattering parameters of individual photons, extends the number of variable parameters of previous works, and allows for more flexible geometries. Here we focus on the influence of bulk velocity of the accreted matter on the CRSF line shapes and positions.

  13. Ion cyclotron emission by spontaneous emission

    Energy Technology Data Exchange (ETDEWEB)

    Da Costa, O. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Gresillon, D. [Ecole Polytechnique, 91 - Palaiseau (France). Lab. de Physique des Milieux Ionises

    1994-07-01

    The goal of the study is to examine whether the spontaneous emission can account for ICE (ion cyclotron emission) experimental results, or part of them. A straightforward approach to plasma emission is chosen, investigating the near equilibrium wave radiation by gyrating ions, and thus building from the majority and fast fusion ions the plasma fluctuations and emission on the fast magnetoacoustic or compressional Alfven wave mode in the IC frequency range. Similarities with the ICE experiments are shown: the emission temperature in the presence of fast ions (even in a very small amount), the strong fast ion emission increase with the harmonic, the fine double-line splitting of each peak, the linear but not proportional increase of the peak width with the harmonic. 3 refs., 2 figs.

  14. Prospects for advanced electron cyclotron resonance and electron beam ion source charge breeding methods for EURISOL

    Energy Technology Data Exchange (ETDEWEB)

    Delahaye, P.; Jardin, P.; Maunoury, L.; Traykov, E.; Varenne, F. [GANIL, CEA/DSM-CNRS/IN2P3, Bd. Becquerel, BP 55027, 14076 Caen Cedex 05 (France); Galata, A.; Porcellato, A. M.; Prete, G. F. [INFN-Laboratori Nazionali di Legnaro, Viale dell' Universita 2, 35020 Legnaro, Padova (Italy); Angot, J.; Lamy, T.; Sortais, P.; Thuillier, T. [LPSC Grenoble, 53, rue des Martyrs, 38026 Grenoble Cedex (France); Ban, G. [LPC Caen, 6 bd Marechal Juin, 14050 Caen Cedex (France); Celona, L.; Lunney, D. [INFN-Laboratori Nazionali del Sud, via S.Sofia 62, 95125 Catania (Italy); Choinski, J.; Gmaj, P.; Jakubowski, A.; Steckiewicz, O. [Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5a, 02 093 Warsaw (Poland); Kalvas, T. [Department of Physics, University of Jyvaeskylae, PB 35 (YFL) 40351 Jyvaeskylae (Finland); and others

    2012-02-15

    As the most ambitious concept of isotope separation on line (ISOL) facility, EURISOL aims at producing unprecedented intensities of post-accelerated radioactive isotopes. Charge breeding, which transforms the charge state of radioactive beams from 1+ to an n+ charge state prior to post-acceleration, is a key technology which has to overcome the following challenges: high charge states for high energies, efficiency, rapidity and purity. On the roadmap to EURISOL, a dedicated R and D is being undertaken to push forward the frontiers of the present state-of-the-art techniques which use either electron cyclotron resonance or electron beam ion sources. We describe here the guidelines of this R and D.

  15. Semi-classical quantum theory for cyclotron radiation

    Institute of Scientific and Technical Information of China (English)

    陈军锋; 邓劲松; 徐毅; 尤峻汉

    1997-01-01

    A semi-classical quantum theory of the cyclotron radiation of the nonrelativistic thermal electrons in a very strong magnetic field is presented.The basic formulae of the absorption coefficient of cyclotron resonance kv and the absorption (scattering) cross-section of cyclotron resonance σv have been derived under the quadrupole approximation.σv is an important quantity in the study of the "magnetic inverse-Compton scattering".It is shown that σv is greatly larger than the Thomson cross-sectron σT,which is important in discussing the magnetic inverse-Compton scattering of the relativistic electrons in a very strong magnetic field.

  16. Accelerators for hadrontherapy: From Lawrence cyclotrons to linacs

    Science.gov (United States)

    Amaldi, U.; Bonomi, R.; Braccini, S.; Crescenti, M.; Degiovanni, A.; Garlasché, M.; Garonna, A.; Magrin, G.; Mellace, C.; Pearce, P.; Pittà, G.; Puggioni, P.; Rosso, E.; Verdú Andrés, S.; Wegner, R.; Weiss, M.; Zennaro, R.

    2010-08-01

    Hadrontherapy with protons and carbon ions is a fast developing methodology in radiation oncology. The accelerators used and planned for this purpose are reviewed starting from the cyclotrons used in the thirties. As discussed in the first part of this paper, normal and superconducting cyclotrons are still employed, together with synchrotrons, for proton therapy while for carbon ion therapy synchrotrons have been till now the only option. The latest developments concern a superconducting cyclotron for carbon ion therapy, fast-cycling high frequency linacs and 'single room' proton therapy facilities. These issues are discussed in the second part of the paper by underlining the present challenges, in particular the treatment of moving organs.

  17. Improving cancer treatment with cyclotron produced radionuclides. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Larson, S.M.; Finn, R.D.

    1993-11-01

    This report describes our continuing long term goal of promoting nuclear medicine applications by improving the scientific basis for tumor diagnosis, treatment and treatment follow-up based on the use of cyclotron produced radiotracers in oncology. The program includes 3 interactive components: Radiochemistry/Cyclotron; Pharmacology; and Immunology. An essential strategy is as follows: novel radionuclides and radiotracers developed in the Radiochemistry/Cyclotron section will be employed in the Pharmacology and Immunology sections during the next year. The development of novel radionuclides and tracers is of course useful in and of itself, but their utility is greatly enhanced by the interaction with the immunology and pharmacology components of the program.

  18. High-current cyclotron to drive an electronuclear assembly

    CERN Document Server

    Alenitsky, Yu G

    2002-01-01

    The proposal on creation of a high-current cyclotron complex for driving an electronuclear assembly reported at the 17th Meeting on Accelerators of Charged Particles is discussed. Some changes in the basic design parameters of the accelerator are considered in view of new results obtained in the recent works. It is shown that the cyclotron complex is now the most real and cheapest accelerator for production of proton beams with a power of up to 10 MW. Projects on design of a high-current cyclotron complex for driving an electronuclear subcritical assembly are presented.

  19. Total on-line purchasing system (TOPS)

    Energy Technology Data Exchange (ETDEWEB)

    Collins, N.

    1995-11-01

    The Information Management Division (IMD) at LLNL is developing a new purchasing system for the Procurement Department. The first major development of this new system is called, {open_quotes}Total On-Line Purchasing System{close_quotes} (TOPS). TOPS will help speed up the requisitioning process by having requisitions electronically entered by requesters and electronically sent to buyers to be put on Purchase Orders. The new purchasing system will use Electronic Commerce (EC)/Electronic Data Interchange (EDI), to help increase transaction flows for shipping notices, RFQs, Quotes, Purchase Orders, and Invoices. ANSI X.12 is the EDI standard that this new EC will use.

  20. Undergraduate Education with the Rutgers 12-Inch Cyclotron

    Science.gov (United States)

    Koeth, Timothy W.

    The Rutgers 12-Inch Cyclotron is a research grade accelerator dedicated to undergraduate education. From its inception, it has been intended for instruction and has been designed to demonstrate classic beam physics phenomena and provides students hands on experience with accelerator technology. The cyclotron is easily reconfigured, allowing experiments to be designed and performed within one academic semester. Our cyclotron offers students the opportunity to operate an accelerator and directly observe many fundamental beam physics concepts, including axial and radial betatron motion, destructive resonances, weak and azimuthally varying field (AVF) focusing schemes, RF and DEE voltage effects, diagnostic techniques, and perform low energy nuclear reactions. This paper emphasizes the unique beam physics measurements and beam manipulations capable at the Rutgers 12-Inch Cyclotron.

  1. Performance of a CW RFQ Injector for the IUCF Cyclotron

    CERN Document Server

    Derenchuk, Vladimir Peter; East, Gary W; Friesel, Dennis; Hamm, Robert W; Jones, William P; Staples, John W

    2005-01-01

    A 750 keV RFQ proton pre-injector was installed in place of a 600 keV Cockroft-Walton high voltage terminal for the IUCF k220 Cyclotron.* The pre-injector consists of a 20 keV microwave ion source and LEBT, a unique design 750 keV CW RFQ, and a short transfer beam line to the k15 injector cyclotron center region.** This pre-injector system was installed and commissioned in June of 2003 and is now in routine service as the sole injection system to the cyclotrons. This contribution will discuss the performance of the CW RFQ pre-injector and the transmission properties of the beam through the cyclotrons.

  2. Design Study Of Cyclotron Magnet With Permanent Magnet

    Science.gov (United States)

    Kim, Hyun Wook; Chai, Jong Seo

    2011-06-01

    Low energy cyclotrons for Positron emission tomography (PET) have been wanted for the production of radio-isotopes after 2002. In the low energy cyclotron magnet design, increase of magnetic field between the poles is needed to make a smaller size of magnet and decrease power consumption. The Permanent magnet can support this work without additional electric power consumption in the cyclotron. In this paper the study of cyclotron magnet design using permanent magnet is shown and also the comparison between normal magnet and the magnet which is designed with permanent magnet is shown. Maximum energy of proton is 8 MeV and RF frequency is 79.3 MHz. 3D CAD design was done by CATIA P3 V5 R18 [1] and the All field calculations had been performed by OPERA-3D TOSCA [2]. The self-made beam dynamics program OPTICY [3] is used for making isochronous field and other calculations.

  3. The fundamental cyclotron line in 4U 1538-52

    CERN Document Server

    Rodes-Roca, J J; Bernabéu, J G

    2009-01-01

    We present pulse phase averaged spectra of the high mass X-ray binary pulsar 4U 1538-52/QV Nor. Observations of this persistent accreting pulsar were made with the Rossi X-ray Timing Explorer (RXTE). We study the variability of cyclotron resonant scattering feature (CRSF or simply cyclotron line) in the high energy spectra of this binary system. We show that the parameters of the CRSF are correlated. The first one is, as suggested by theory, between the width and the energy of the cyclotron line. The second one is between the relative width and the optical depth of the cyclotron line. We discuss these results with studies of other X-ray pulsars and their implications on the line variability.

  4. Single-electron detection and spectroscopy via relativistic cyclotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Asner, David M.; Bradley, Rich; De Viveiros Souza Filho, Luiz A.; Doe, Peter J.; Fernandes, Justin L.; Fertl, M.; Finn, Erin C.; Formaggio, Joseph; Furse, Daniel L.; Jones, Anthony M.; Kofron, Jared N.; LaRoque, Benjamin; Leber, Michelle; MCBride, Lisa; Miller, M. L.; Mohanmurthy, Prajwal T.; Monreal, Ben; Oblath, Noah S.; Robertson, R. G. H.; Rosenberg, Leslie; Rybka, Gray; Rysewyk, Devyn M.; Sternberg, Michael G.; Tedeschi, Jonathan R.; Thummler, Thomas; VanDevender, Brent A.; Woods, N. L.

    2015-04-01

    It has been understood since 1897 that accelerating charges should emit electromagnetic radiation. Cyclotron radiation, the particular form of radiation emitted by an electron orbiting in a magnetic field, was first derived in 1904. Despite the simplicity of this concept, and the enormous utility of electron spectroscopy in nuclear and particle physics, single-electron cyclotron radiation has never been observed directly. Here we demonstrate single-electron detection in a novel radiofrequency spectrometer. We observe the cyclotron radiation emitted by individual electrons that are produced with mildly-relativistic energies by a gaseous radioactive source and are magnetically trapped. The relativistic shift in the cyclotron frequency permits a precise electron energy measurement. Precise beta electron spectroscopy from gaseous radiation sources is a key technique in modern efforts to measure the neutrino mass via the tritium decay endpoint, and this work is a proof-of-concept for future neutrino mass experiments using this technique.

  5. Cyclotron mode frequency shifts in multi-species ion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Affolter, M.; Anderegg, F.; Dubin, D.H.E.; Driscoll, C.F.

    2014-06-27

    In trapped plasmas, electric fields and collective effects shift the cyclotron mode frequencies away from the “bare” cyclotron frequency for each species s. Here, these shifts are measured on a set of cyclotron modes (m=0,1, and 2) with cos(mθ) azimuthal dependence in near rigid-rotor multi-species ion plasmas. We observe that these frequency shifts are dependent on the plasma density, through the E×B rotation frequency f{sub E}, and on the “local” charge concentration δ{sub s} of species s, in close agreement with theory. - Highlights: • Cyclotron modes varying as sin(mθ) with m=0,1and2 are detected. • These mode frequencies shift by factors of the ExB rotation frequency. • These frequency shifts depend on the species charge fraction and radial distribution. • Centrifugal separation of species can greatly modify these frequency shifts.

  6. Cryogenic system for VECC K500 superconducting cyclotron

    CERN Document Server

    Pal, G; Bhattacharyya, T K; Bhandari, R K

    2009-01-01

    VEC Centre, Kolkata in India is at an advanced stage of commissioning a K500 superconducting cyclotron. The superconducting coil of the magnet for cyclotron is cooled by liquid helium. Three liquid helium cooled cryopanels, placed inside the Dees of the radiofrequency system, maintain the vacuum in the acceleration region of the superconducting cyclotron. The cryogenic system for magnet for cyclotron has been tested by cooling the coil and energizing the magnet. The cryogenic system for cryopanels has also been tested. Heater and temperature sensor were placed on the liquid helium cold head for cryopanel. The temperature of the cold head was observed to be below 20 K upto a heat load of 11.7 watt.

  7. Design of 10 MeV cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    R Solhju

    2015-09-01

    Full Text Available Design and construction of 10MeV cyclotron has been started at Amirkabir University of Technology since 2012. So far, the conceptual and detail engineering design phases have been finalized. The main purpose of this baby cyclotron is to generate proton beam for the production of PET radioisotopes. The cyclotron consists of magnet, cavity, ion source, RF and LLRF system, vacuum system, cooling system, power amplifiers and power supplies system. In this paper, a brief of design principles for all the parts of cyclotron and their final simulation results is presented. It should be noted that these simulations have been performed and optimized by the most accurate softwares such as TOSCA, ANSYS, HFSS, SolidWorks and CST. Also, the manufacturing feasibility of all the parts is performed and their dimensions and parameters are synchronized with manufacturing standards

  8. Maryland University sectored isochronous cyclotron (MUSIC): Progress report No. 32

    Energy Technology Data Exchange (ETDEWEB)

    1968-06-28

    Completion of magnet tests, followed by completion of installation of major cyclotron components, are reported. Intermediate level power tests of the rf system are also reported. Design and fabrication of the control system are reported to be under way. (LEW)

  9. Maryland University sectored isochronous cyclotron (MUSIC): Progress report No. 26

    Energy Technology Data Exchange (ETDEWEB)

    1968-01-17

    Progress is reported in the fabrication, installation, and testing of cyclotron components, including magnets and coils, rf components, vacuum and control equipment. Also reported are magnet and rf component measurements. (LEW)

  10. Maryland University sectored isochronous cyclotron (MUSIC): Progress report No. 23

    Energy Technology Data Exchange (ETDEWEB)

    1967-10-09

    Progress is reported in the design, installation of various components of the cyclotron, including coils, magnets, rf system, and vacuum system. Also reported are measurements on magnets and rf components. (LEW)

  11. Maryland University sectored isochronous cyclotron (MUSIC): Progress report No. 20

    Energy Technology Data Exchange (ETDEWEB)

    1967-06-30

    Progress is reported in the fabrication and testing of cyclotron components, including magnet system and rf system components. Work on vacuum components and instrumentation and control equipment is also reported. (LEW)

  12. Variable-Energy Cyclotron for Proton Therapy Application

    CERN Document Server

    Alenitsky, Yu G; Vorozhtsov, A S; Glazov, A A; Mytsyn, G V; Molokanov, A G; Onishchenko, L M

    2004-01-01

    The requirements to characteristics of the beams used for proton therapy are considered. The operation and proposed cyclotrons for proton therapy are briefly described. The technical decisions of creation of the cyclotron with energy variation in the range 70-230 MeV and with current up to 100 nA are estimated. Taking into account the fact, that the size and cost of the cyclotron are approximately determined by the maximum proton energy, it is realistically offered to limit the maximum proton energy to 190 MeV and to elaborate a cyclotron project with a warm winding of the magnet for acceleration of H^{-} ions. The energy of the extracted protons for each run is determined by a stripped target radius in the vacuum chamber of the accelerator, and the radiation dose field for the patient is created by the external devices using the developed techniques.

  13. Fusion Reactivity in the Case of Ion Cyclotron Resonant Heating

    Institute of Scientific and Technical Information of China (English)

    俞国扬; 常永斌; 沈林芳

    2003-01-01

    By applying the integral-variable-change technique,an explicit expression of deuterium-tritium fusion reactivity in the case of second harmonic ion cyclotron resonant heating on deuterium is obtained.

  14. On-line and Mobil Learning Activities

    Science.gov (United States)

    Ackerman, S. A.; Whittaker, T. M.; Jasmin, T.; Mooney, M. E.

    2012-12-01

    Introductory college-level science courses for non-majors are critical gateways to imparting not only discipline-specific information, but also the basics of the scientific method and how science influences society. They are also indispensable for student success to degree. On-line, web-based homework (whether on computers or mobile devices) is a rapidly growing use of the Internet and is becoming a major component of instruction in science, replacing delayed feedback from a few major exams. Web delivery and grading of traditional textbook-type questions is equally effective as having students write them out for hand grading, as measured by student performance on conceptual and problem solving exams. During this presentation we will demonstrate some of the interactive on-line activities used to teach concepts and how scientists approach problem solving, and how these activities have impacted student learning. Evaluation of the activities, including formative and summative, will be discussed and provide evidence that these interactive activities significantly enhance understanding of introductory meteorological concepts in a college-level science course. More advanced interactive activities are also used in our courses for department majors, some of these will be discussed and demonstrated. Bring your mobile devices to play along! Here is an example on teaching contouring: http://profhorn.aos.wisc.edu/wxwise/contour/index.html

  15. Ion-Beam-Excited Electrostatic Ion Cyclotron Waves

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens;

    1976-01-01

    Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field.......Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field....

  16. On-line chemical composition analyzer development

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, M.J.; Garrison, A.A.; Muly, E.C.; Moore, C.F.

    1992-02-01

    The energy consumed in distillation processes in the United States represents nearly three percent of the total national energy consumption. If effective control of distillation columns can be accomplished, it has been estimated that it would result in a reduction in the national energy consumption of 0.3%. Real-time control based on mixture composition could achieve these savings. However, the major distillation processes represent diverse applications and at present there does not exist a proven on-line chemical composition sensor technology which can be used to control these diverse processes in real-time. This report presents a summary of the findings of the second phase of a three phase effort undertaken to develop an on-line real-time measurement and control system utilizing Raman spectroscopy. A prototype instrument system has been constructed utilizing a Perkin Elmer 1700 Spectrometer, a diode pumped YAG laser, two three axis positioning systems, a process sample cell land a personal computer. This system has been successfully tested using industrially supplied process samples to establish its performance. Also, continued application development was undertaken during this Phase of the program using both the spontaneous Raman and Surface-enhanced Raman modes of operation. The study was performed for the US Department of Energy, Office of Industrial Technologies, whose mission is to conduct cost-shared R D for new high-risk, high-payoff industrial energy conservation technologies. Although this document contains references to individual manufacturers and their products, the opinions expressed on the products reported do not necessarily reflect the position of the Department of Energy.

  17. Aprender a innovar: una experiencia on line

    Directory of Open Access Journals (Sweden)

    Joaquín MORENO MARCHAL

    2014-11-01

    Full Text Available La creatividad y la innovación se han convertido en recursos clave en la denominada sociedad del conocimiento, que bien podría ser también llamada sociedad de la innovación. Pero innovar es una actividad compleja, que integra la aplicación de múltiples capacidades, el pensamiento divergente y convergente, la gestión de equipos humanos, la comunicación. Ahora bien, a innovar se puede, y se debe, aprender. Aprender a innovar es un reto y también una obligación para el conjunto del sistema educativo en todos sus niveles. Partiendo de estas consideraciones este trabajo expone una experiencia de aprendizaje de la creatividad y de la innovación a través de un curso totalmente on line basado en la plataforma MOODLE, en el marco del Programa de Formación Permanente de la Universidad de Cádiz. Se presenta un modelo del proceso de innovación, denominado CREALAB, de elaboración propia. Este modelo se ha utilizado como base del proceso de aprendizaje de la creatividad y de la innovación y en el diseño del curso, está organizado en torno a actividades y tiene un carácter iterativo y realimentado. Se presentan además el conjunto del diseño metodológico y los resultados obtenidos en las dos ediciones celebradas hasta el momento. El diseño del curso totalmente on line y los resultados alcanzados permiten estimar un alto potencial de aplicación, tanto a nivel personal como a nivel organizacional.

  18. Electron cyclotron emission diagnostic for ITER.

    Science.gov (United States)

    Rowan, W; Austin, M; Beno, J; Ellis, R; Feder, R; Ouroua, A; Patel, A; Phillips, P

    2010-10-01

    Electron temperature measurements and electron thermal transport inferences will be critical to the nonactive and deuterium phases of ITER operation and will take on added importance during the alpha heating phase. The diagnostic must meet stringent criteria on spatial coverage and spatial resolution during full field operation. During the early phases of operation, it must operate equally well at half field. The key to the diagnostic is the front end design. It consists of a quasioptical antenna and a pair of calibration sources. The radial resolution of the diagnostic is less than 0.06 m. The spatial coverage extends at least from the core to the separatrix with first harmonic O-mode being used for the core and second harmonic X-mode being used for the pedestal. The instrumentation used for the core measurement at full field can be used for detection at half field by changing the detected polarization. Intermediate fields are accessible. The electron cyclotron emission systems require in situ calibration, which is provided by a novel hot calibration source. The critical component for the hot calibration source, the emissive surface, has been successfully tested. A prototype hot calibration source has been designed, making use of extensive thermal and mechanical modeling.

  19. Influence of visualization on consumption during on-line shopping

    OpenAIRE

    Hictaler, Urška

    2013-01-01

    This diploma work studies the influence of visualization on consumption during on-line shopping. The first part of the thesis starts with key areas of visualization, consumption and on-line shopping. Visualization, areas of use, human perception and ways of product presentation in on-line shops are defined discussed first. Next, consumption, consumers and factors that influence their decisions and satisfaction are defined. The last topic in the first part of the thesis discusses on-line shopp...

  20. A small low energy cyclotron for radioisotope measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bertsche, K.J.

    1989-11-01

    Direct detection of {sup 14}C by accelerator mass spectrometry has proved to be a much more sensitive method for radiocarbon dating than the decay counting method invented earlier by Libby. A small cyclotron (the cyclotrino'') was proposed for direct detection of radiocarbon in 1980. This combined the suppression of background through the use of negative ions, which had been used effectively in tandem accelerators, with the high intrinsic mass resolution of a cyclotron. Development of a small electrostatically-focused cyclotron for use as a mass spectrometer was previously reported but the sensitivity needed for detection of {sup 14}C at natural abundance was not achieved. The major contributions of this work are the integration of a high current external ion source with a small flat-field, electrostatically-focused cyclotron to comprise a system capable of measuring {sup 14}C at natural levels, and the analysis of ion motion in such a cyclotron, including a detailed analysis of phase bunching and its effect on mass resolution. A high current cesium sputter negative ion source generates a beam of carbon ions which is pre-separated with a Wien filter and is transported to the cyclotron via a series of electrostatic lenses. Beam is injected radially into the cyclotron using electrostatic deflectors and an electrostatic mirror. Axial focusing is entirely electrostatic. A microchannel plate detector is used with a phase-grated output. In its present form the system is capable of improving the sensitivity of detecting {sup 14}C in some biomedical experiments by a factor of 10{sup 4}. Modifications are discussed which could bring about an additional factor of 100 in sensitivity, which is important for archaeological and geological applications. Possibilities for measurements of other isotopes, such as {sup 3}H, and {sup 10}Be, and {sup 26}Al, are discussed. 70 refs.

  1. A Distributed System for Learning Programming On-Line

    Science.gov (United States)

    Verdu, Elena; Regueras, Luisa M.; Verdu, Maria J.; Leal, Jose P.; de Castro, Juan P.; Queiros, Ricardo

    2012-01-01

    Several Web-based on-line judges or on-line programming trainers have been developed in order to allow students to train their programming skills. However, their pedagogical functionalities in the learning of programming have not been clearly defined. EduJudge is a project which aims to integrate the "UVA On-line Judge", an existing…

  2. On-Line Learning: One Way to Bring People Together

    Science.gov (United States)

    Goff-Kfouri, Carol Ann

    2006-01-01

    The purpose of this study was to demonstrate the benefits of on-line learning for adult learners and to further demystify three common misconceptions concerning on-line learning: students certainly do receive support from their on-line professors, the professor is pro-active rather than passive, and students may be more motivated to learn than in…

  3. SOL: INNOVACIÓN ON-LINE

    Directory of Open Access Journals (Sweden)

    Rubén Faúndez

    2007-11-01

    Full Text Available Las aplicaciones de simulación tienden a ser cada vez más cercanas a usuarios e industrias. Sin embargo, muchas de ellas no poseen ni la capacidad ni el conocimiento como para desarrollar internamente sus modelos de simulación. Por este motivo, y como una forma de apoyar la toma de decisiones basándose en modelos de simulación, se presenta la plataforma SOL (Simulación On Line. La metodología completa de trabajo, así como la interacción entre SOL, Empresa y Asesor, son presentadas. Su base de datos, los niveles de usuarios, sus funcionalidades, y la creación automatizada de información grafica y visual, también son explicadas. En el caso de aplicación, el uso de SOL para apoyar la toma de decisiones en una operación de movimiento de material, permite a los tomadores de decisión acceder a análisis robustos basados en información extraída de los modelos de simulación. SOL, al almacenar información, funcionar vía web, generar análisis automatizados y crear visualizaciones, permite cumplir con las expectativas de los usuarios respecto a una solución integral en simulación.

  4. On-Line Impact Load Identification

    Directory of Open Access Journals (Sweden)

    Krzysztof Sekuła

    2013-01-01

    Full Text Available The so-called Adaptive Impact Absorption (AIA is a research area of safety engineering devoted to problems of shock absorption in various unpredictable scenarios of collisions. It makes use of smart technologies (systems equipped with sensors, controllable dissipaters and specialised tools for signal processing. Examples of engineering applications for AIA systems are protective road barriers, automotive bumpers or adaptive landing gears. One of the most challenging problems for AIA systems is on-line identification of impact loads, which is crucial for introducing the optimum real-time strategy of adaptive impact absorption. This paper presents the concept of an impactometer and develops the methodology able to perform real-time impact load identification. Considered dynamic excitation is generated by a mass M1 impacting with initial velocity V0. An analytical formulation of the problem, supported with numerical simulations and experimental verifications is presented. Two identification algorithms based on measured response of the impacted structure are proposed and discussed. Finally, a concept of the AIA device utilizing the idea of impactometer is briefly presented.

  5. Cyclotron-based of plant gravisensing

    Science.gov (United States)

    Kordyum, E.; Kalinina, Ia.; Bogatina, N.; Kondrachuk, A.

    Roots exhibit positive gravitropism they grow in the direction of a gravitational vector while shoots respond negatively and grow opposite to a gravitational vector We first demonstrated the inversion of roots gravitropism from positive to negative one under gravistimulation in the weak combined magnetic field WCMF consisted of permanent magnetic field PMF with the magnitude of order of 50 mu T and altering magnetic field AMF with the 6 mu T magnitude and a frequency of 32 Hz It was found that the effect of inversion has a resonance nature It means that in the interval of frequencies 1-45 Hz inversion of root gravitropism occurs only at frequency 32 Hz 2-3-day old cress seedlings were gravistimulated in moist chambers which are placed in mu -metal shields Inside mu -metal shields combined magnetic fields have been created The magnitude of magnetic fields was measured by a flux-gate magnetometer Experiments were performed in darkness at temperature 20 pm 1 0 C We measured the divergence angle of a growing root from its horizontal position After 1 h of gravistimulation in the WCMF we observed negative gravitropism of cress roots i e they grow in the opposite direction to a gravitational vector Frequency of 32 Hz for the magnitude of the PMF applied formally corresponds to cyclotron frequency of Ca 2 ions This indicates possible participation of calcium ions in root gravitropism There are many evidences of resonance effects of the WCMF on the biological processes that involve Ca 2 but the nature of

  6. Electric and Magnetic Vertical Focusing Study for 100 MeV High Intensity Proton Cyclotron

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>For the central region design of cyclotrons, the basic problem in the vertical motion is very different from the one in the radial motion. The reason is that vertical tune is almost zero at the center of cyclotrons,

  7. Accelerators for hadrontherapy: From Lawrence cyclotrons to linacs

    Energy Technology Data Exchange (ETDEWEB)

    Amaldi, U.; Bonomi, R.; Braccini, S., E-mail: Saverio.Braccini@cern.ch; Crescenti, M.; Degiovanni, A.; Garlasche, M.; Garonna, A.; Magrin, G.; Mellace, C.; Pearce, P.; Pitta, G.; Puggioni, P.; Rosso, E.; Verdu Andres, S.; Wegner, R.; Weiss, M.; Zennaro, R.

    2010-08-21

    Hadrontherapy with protons and carbon ions is a fast developing methodology in radiation oncology. The accelerators used and planned for this purpose are reviewed starting from the cyclotrons used in the thirties. As discussed in the first part of this paper, normal and superconducting cyclotrons are still employed, together with synchrotrons, for proton therapy while for carbon ion therapy synchrotrons have been till now the only option. The latest developments concern a superconducting cyclotron for carbon ion therapy, fast-cycling high frequency linacs and 'single room' proton therapy facilities. These issues are discussed in the second part of the paper by underlining the present challenges, in particular the treatment of moving organs.

  8. Accelerators for hadrontherapy: From Lawrence cyclotrons to linacs

    CERN Document Server

    Braccini, S; Garlasche, M; Weiss, M; Crescenti, M; Pearce, P; Rosso, E; Wegner, R; Magrin, G; Pitta, G; Amaldi, U; Puggioni, P; Degiovanni, A; Mellace, C; Zennaro, R; Bonomi, R; Garonna, A

    2010-01-01

    Hadrontherapy with protons and carbon ions is a fast developing methodology in radiation oncology. The accelerators used and planned for this purpose are reviewed starting from the cyclotrons used in the thirties. As discussed in the first part of this paper, normal and superconducting cyclotrons are still employed, together with synchrotrons, for proton therapy while for carbon ion therapy synchrotrons have been till now the only option. The latest developments concern a superconducting cyclotron for carbon ion therapy, fast-cycling high frequency linacs and `single room' proton therapy facilities. These issues are discussed in the second part of the paper by underlining the present challenges, in particular the treatment of moving organs. (C) 2010 Elsevier B.V. All rights reserved.

  9. Cassini observations of ion cyclotron waves and ions anisotropy

    Science.gov (United States)

    Crary, F. J.; Dols, V. J.; Cassidy, T. A.; Tokar, R. L.

    2013-12-01

    In Saturn's equatorial, inner magnetosphere, the production of fresh ions in a pick-up distribution generates ion cyclotron waves. These waves are a sensitive indicator of fresh plasma production, but the quantitative relation between wave properties and ionization rates is nontrivial. We present a combined analysis of Cassini MAG and CAPS data, from a variety of equatorial orbits between 2005 and 2012. Using the MAG data, we determine the amplitude and peak frequency of ion cyclotron waves. From the CAPS data we extract the parallel and perpendicular velocity distribution of water group ions. We compare these results with hybrid simulations of the ion cyclotron instability and relate the observed wave amplitudes and ion velocity distributions to the production rate of pickup ions. The resulting relation between wave and plasma properties will allow us to infer ion production rates even at times when no direct ion measurements are available.

  10. Design study of the KIRAMS-430 superconducting cyclotron magnet

    Science.gov (United States)

    Kim, Hyun Wook; Kang, Joonsun; Hong, Bong Hwan; Jung, In Su

    2016-07-01

    Design study of superconducting cyclotron magnet for the carbon therapy was performed at the Korea Institute of Radiological and Medical Science (KIRAMS). The name of this project is The Korea Heavy Ion Medical Accelerator (KHIMA) project and a fixed frequency cyclotron with four spiral sector magnet was one of the candidate for the accelerator type. Basic parameters of the cyclotron magnet and its characteristics were studied. The isochronous magnetic field which can guide the 12C6+ ions up to 430 MeV/u was designed and used for the single particle tracking simulation. The isochronous condition of magnetic field was achieved by optimization of sector gap and width along the radius. Operating range of superconducting coil current was calculated and changing of the magnetic field caused by mechanical deformations of yokes was considered. From the result of magnetic field design, structure of the magnet yoke was planned.

  11. Vertical Electron Cyclotron Emission Diagnostic for TCV Plasmas

    Directory of Open Access Journals (Sweden)

    Goodman T. P.

    2012-09-01

    Full Text Available Electron cyclotron resonance heating (ECRH and electron cyclotron current drive (ECCD are used to heat the plasma, to tailor the current profiles and to achieve different operating regimes of tokamak plasmas. Plasmas with ECRH/ECCD are characterized by non-thermal electrons, which cannot be described by a Maxwellian distribution. Non-thermal electrons are also generated during MHD activity, like sawteeth crashes. Quantifying the non-thermal electron distribution is therefore a key for understanding EC heated fusion plasmas. For this purpose a vertical electron cyclotron emission (V-ECE diagnostic is being installed at TCV. The diagnostic layout, the calibration, the analysis technique for data interpretation, the physics potentials and limitations are discussed.

  12. A strong-focusing 800 MeV cyclotron for high-current applications

    Science.gov (United States)

    Pogue, N.; Assadi, S.; Badgley, K.; Comeaux, J.; Kellams, J.; McInturff, A.; McIntyre, P.; Sattarov, A.

    2013-04-01

    A superconducting strong-focusing cyclotron (SFC) is being developed for high-current applications. It incorporates four innovations. Superconducting quarter-wave cavities are used to provide >20 MV/turn acceleration. The orbit separation is thereby opened so that bunch-bunch interactions between successive orbits are eliminated. Quadrapole focusing channels are incorporated within the sectors so that alternating-gradient strong-focusing transport is maintained throughout. Dipole windings on the inner and outer orbits provide enhanced control for injection and extraction of bunches. Finally each sector magnet is configured as a flux-coupled stack of independent apertures, so that any desired number of independent cyclotrons can be integrated within a common footprint. Preliminary simulations indicate that each SFC should be capable of accelerating 10 mA CW to 800 MeV with very low loss and >50% energy efficiency. A primary motivation for SFC is as a proton driver for accelerator-driven subcritical fission in a molten salt core. The cores are fueled solely with the transuranics from spent nuclear fuel from a conventional nuclear power plant. The beams from one SFC stack would destroy all of the transuranics and long-lived fission products that are produced by a GWe reactor [1]. This capability offers the opportunity to close the nuclear fuel cycle and provide a path to green nuclear energy.

  13. Direct Technetium radiopharmaceuticals production using a 30MeV Cyclotron

    Directory of Open Access Journals (Sweden)

    M Kamali Dehgan

    2011-07-01

    Full Text Available Background and purpose of the study: Technetium-99m is the major radionuclide used in the world and mainly is provided by fission product. However extensive research has been conducted on the use of accelerators for production of 99mTc. This investigation reports the production of 99mTc radioisotope using cyclotrons followed by the preparation, quality control and biodistribution studies of four major Tc-radiopharmaceuticals. Methods: The high purity molybdenum natural target (130mg/cm2 was irradiated in a Cyclone 30 accelerator using 160 µA of 25 MeV proton beam energy for 1000 µA-h. After dissolution, the technetium radionuclides were extracted using methyl ethyl ketone (MEK followed by preparation of Tc-MIBI, Tc-DTPA, Tc-DMSA and Tc-phytate as radiopharmaceutical samples. Results: The results of quality controls and animal biodistribution studies showed successful production of Tc radionuclides (including 99mTc in the bombarded target and subsequent labelling of the kit with Tc. Conclusion: The developed high power Mo target if constructed using enriched 100Mo, could be a practical method for large-scale production of 99mTc and promising as an alternative to fission product 99Mo-99mTc generators for local applications near cyclotron facilities.

  14. A solvent-extraction module for cyclotron production of high-purity technetium-99m.

    Science.gov (United States)

    Martini, Petra; Boschi, Alessandra; Cicoria, Gianfranco; Uccelli, Licia; Pasquali, Micòl; Duatti, Adriano; Pupillo, Gaia; Marengo, Mario; Loriggiola, Massimo; Esposito, Juan

    2016-12-01

    The design and fabrication of a fully-automated, remotely controlled module for the extraction and purification of technetium-99m (Tc-99m), produced by proton bombardment of enriched Mo-100 molybdenum metallic targets in a low-energy medical cyclotron, is here described. After dissolution of the irradiated solid target in hydrogen peroxide, Tc-99m was obtained under the chemical form of (99m)TcO4(-), in high radionuclidic and radiochemical purity, by solvent extraction with methyl ethyl ketone (MEK). The extraction process was accomplished inside a glass column-shaped vial especially designed to allow for an easy automation of the whole procedure. Recovery yields were always >90% of the loaded activity. The final pertechnetate saline solution Na(99m)TcO4, purified using the automated module here described, is within the Pharmacopoeia quality control parameters and is therefore a valid alternative to generator-produced (99m)Tc. The resulting automated module is cost-effective and easily replicable for in-house production of high-purity Tc-99m by cyclotrons.

  15. Electron cyclotron emission diagnostics on the large helical device

    Science.gov (United States)

    Nagayama, Y.; Kawahata, K.; England, A.; Ito, Y.; Bretz, N.; McCarthy, M.; Taylor, G.; Doane, J.; Ikezi, H.; Edlington, T.; Tomas, J.

    1999-01-01

    The electron cyclotron emission (ECE) diagnostic system is installed on the large helical device (LHD). The system includes the following instruments: a heterodyne radiometer, a Michelson spectrometer, and a grating polychromator. A 63.5 mm corrugated waveguide system is fully utilized. Large collection optics and notch filters at the frequency of the LHD electron cyclotron heating (ECH) were developed for this system. In addition to these filters, the rectangular waveguide notch filters, the ECE measurement with the radiometer has been successfully performed during the ECH.

  16. Fluid equations in the presence of electron cyclotron current drive

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, Thomas G.; Kruger, Scott E. [Tech-X Corporation, 5621 Arapahoe Avenue, Boulder, Colorado 80303 (United States)

    2012-12-15

    Two-fluid equations, which include the physics imparted by an externally applied radiofrequency source near electron cyclotron resonance, are derived in their extended magnetohydrodynamic forms using the formalism of Hegna and Callen [Phys. Plasmas 16, 112501 (2009)]. The equations are compatible with the closed fluid/drift-kinetic model developed by Ramos [Phys. Plasmas 17, 082502 (2010); 18, 102506 (2011)] for fusion-relevant regimes with low collisionality and slow dynamics, and they facilitate the development of advanced computational models for electron cyclotron current drive-induced suppression of neoclassical tearing modes.

  17. 2D electron cyclotron emission imaging at ASDEX Upgrade (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Classen, I. G. J. [Max Planck Institut fuer Plasmaphysik, 85748 Garching (Germany); FOM-Institute for Plasma Physics, Rijnhuizen, 3430 BE Nieuwegein (Netherlands); Boom, J. E.; Vries, P. C. de [FOM-Institute for Plasma Physics, Rijnhuizen, 3430 BE Nieuwegein (Netherlands); Suttrop, W.; Schmid, E.; Garcia-Munoz, M.; Schneider, P. A. [Max Planck Institut fuer Plasmaphysik, 85748 Garching (Germany); Tobias, B.; Domier, C. W.; Luhmann, N. C. Jr. [University of California at Davis, Davis, California 95616 (United States); Donne, A. J. H. [FOM-Institute for Plasma Physics, Rijnhuizen, 3430 BE Nieuwegein (Netherlands); Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Jaspers, R. J. E. [Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Park, H. K. [POSTECH, Pohang, Gyeongbuk, 790-784 (Korea, Republic of); Munsat, T. [University of Colorado, Boulder, Colorado 80309 (United States)

    2010-10-15

    The newly installed electron cyclotron emission imaging diagnostic on ASDEX Upgrade provides measurements of the 2D electron temperature dynamics with high spatial and temporal resolution. An overview of the technical and experimental properties of the system is presented. These properties are illustrated by the measurements of the edge localized mode and the reversed shear Alfven eigenmode, showing both the advantage of having a two-dimensional (2D) measurement, as well as some of the limitations of electron cyclotron emission measurements. Furthermore, the application of singular value decomposition as a powerful tool for analyzing and filtering 2D data is presented.

  18. Electron Plasmas Cooled by Cyclotron-Cavity Resonance

    CERN Document Server

    Povilus, A P; Evans, L T; Evetts, N; Fajans, J; Hardy, W N; Hunter, E D; Martens, I; Robicheaux, F; Shanman, S; So, C; Wang, X; Wurtele, J S

    2016-01-01

    We observe that high-Q electromagnetic cavity resonances increase the cyclotron cooling rate of pure electron plasmas held in a Penning-Malmberg trap when the electron cyclotron frequency, controlled by tuning the magnetic field, matches the frequency of standing wave modes in the cavity. For certain modes and trapping configurations, this can increase the cooling rate by factors of ten or more. In this paper, we investigate the variation of the cooling rate and equilibrium plasma temperatures over a wide range of parameters, including the plasma density, plasma position, electron number, and magnetic field.

  19. On-line test using multi-foil SiC target at iThemba LABS

    Science.gov (United States)

    Monetti, A.; Bark, R. A.; Andrighetto, A.; Beukes, P.; Conradie, J. L.; Corradetti, S.; Fourie, D.; Lussi, C.; Manzolaro, M.; Meneghetti, G.; Prete, G.; Rossignoli, M.; Scarpa, D.; Van Schalkwyk, P.; Stoddart, N.; Vasquez, J.

    2016-06-01

    In a collaboration between the INFN-SPES project and iThemba LABS, an on-line test of the power dissipation of a multi-slice target concept for radioactive-ion beam production has been performed. Using the 66MeV proton beam from the iThemba LABS Separated Sector Cyclotron, a total power of 4kW was deposited in the target complex, consisting of 13 Silicon Carbide (SiC) discs of about 1 millimetre thickness housed in a graphite cylinder. The results of the measurements fully validate thermal FEM simulations and confirm that the multi-foil target system is a reliable and affordable device for second-generation ISOL-RIB facilities like SPES.

  20. Optimal Design of Proposed 800 MeV Proton Cyclotron Beam Dynamics

    Institute of Scientific and Technical Information of China (English)

    YANG; Jian-jun; LI; Ming; ZHANG; Tian-jue; SONG; Guo-fang; AN; Shi-zhong

    2015-01-01

    The high intensity beam dynamic simulation shows that the theoretic beam current limit of the original design version of the 800 MeV proton cyclotron CYCIEA-800is 1mA.In order to further improve the current limit and reduce beam losses in the cyclotron,the layout of the cyclotron

  1. Robust on-line monitoring of biogas processes; Robusta maettekniker on-line foer optimerad biogasproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Nordberg, Aake; Hansson, Mikael; Kanerot, Mija; Krozer, Anatol; Loefving, Bjoern; Sahlin, Eskil

    2010-03-15

    Although demand for biomethane in Sweden is higher than ever, many Swedish codigestion plants are presently operated below their designed capacity. Efforts must be taken to increase the loading rate and guarantee stable operation and high availability of the plants. There are currently no commercial systems for on-line monitoring, and due to the characteristics of the material, including corrosion and tearing, robust applications have to be developed. The objective of this project was to identify and study different monitoring technologies with potential for on-line monitoring of both substrate mixtures and anaerobic digester content. Based on the prerequisites and demands at Boraas Energi och Miljoe AB's (BEMAB, the municipal energy and waste utility in the city of Boraas, Sweden) biogas plant, the extent of the problems, measurement variables and possible ways of managing these issues have been identified and prioritized. The substrate mixtures in question have a high viscosity and are inhomogeneous with variation in composition, which calls for further homogenization, dilution and filtration to achieve high precision in the necessary analyses. Studies of using different mixers and mills showed that the particle size (800 mum) needed for on-line COD measurement could not be achieved. The problem of homogenization can be avoided if indirect measurement methods are used. Laboratory tests with NIR (near-infra red spectroscopy) showed that VS can be predicted (R2=0,78) in the interval of 2-9% VS. Furthermore, impedance can give a measurement of soluble components. However, impedance is not sensitive enough to give a good measurement of total TS. Microwave technology was installed at the production plant and showed a faster response to changes in TS than the existing TS-sensor. However, due to technical problems, the evaluation only could be done during a limited period of ten days. BEMAB will continue the measurements and evaluation of the instrument. The

  2. Adaptive on-line classification of multi-spectral scanner data

    Science.gov (United States)

    Fromm, F. R.; Northouse, R. A.

    1973-01-01

    A possible solution to the analysis of the massive amounts of multi-spectral scanner data from the Earth Resource Technical Satellite (ERTS) program is proposed. This solution is offered as an adaptive on-line classification scheme. The classifier is described as well as its controller which is based on ground truth data. Cluster analysis is presented as an alternative approach to the ground truth data. Adaptive feature selection is discussed and possible mini-computer implementations are offered.

  3. Characteristics comparison between a cyclotron-based neutron source and KUR-HWNIF for boron neutron capture therapy

    Science.gov (United States)

    Tanaka, H.; Sakurai, Y.; Suzuki, M.; Masunaga, S.; Kinashi, Y.; Kashino, G.; Liu, Y.; Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Maruhashi, A.; Ono, K.

    2009-06-01

    At Kyoto University Research Reactor Institute (KURRI), 275 clinical trials of boron neutron capture therapy (BNCT) have been performed as of March 2006, and the effectiveness of BNCT has been revealed. In order to further develop BNCT, it is desirable to supply accelerator-based epithermal-neutron sources that can be installed near the hospital. We proposed the method of filtering and moderating fast neutrons, which are emitted from the reaction between a beryllium target and 30-MeV protons accelerated by a cyclotron accelerator, using an optimum moderator system composed of iron, lead, aluminum and calcium fluoride. At present, an epithermal-neutron source is under construction from June 2008. This system consists of a cyclotron accelerator, beam transport system, neutron-yielding target, filter, moderator and irradiation bed. In this article, an overview of this system and the properties of the treatment neutron beam optimized by the MCNPX Monte Carlo neutron transport code are presented. The distribution of biological effect weighted dose in a head phantom compared with that of Kyoto University Research Reactor (KUR) is shown. It is confirmed that for the accelerator, the biological effect weighted dose for a deeply situated tumor in the phantom is 18% larger than that for KUR, when the limit dose of the normal brain is 10 Gy-eq. The therapeutic time of the cyclotron-based neutron sources are nearly one-quarter of that of KUR. The cyclotron-based epithermal-neutron source is a promising alternative to reactor-based neutron sources for treatments by BNCT.

  4. DOE-EPRI On-Line Monitoring Implementation Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    E. Davis, R. Bickford

    2003-01-02

    Industry and EPRI experience at several plants has shown on-line monitoring to be very effective in identifying out-of-calibration instrument channels or indications of equipment-degradation problems. The EPRI implementation project for on-line monitoring has demonstrated the feasability of on-line monitoring at several participating nuclear plants. The results have been very enouraging, and substantial progress is anticipated in the coming years.

  5. Effects of Magnetic Shear on Ion-Cyclotron Modes.

    Science.gov (United States)

    Ganguli, Gurudas

    Effects of Magnetic Shear on electrostatic Ion -Bernstein Modes (IBM) are examined. Shear affects the mode structure in 3 principal ways: (i) Local effect, (ii) Global effect and (iii) Orbital effect. The role of shear at the above three levels is investigated for IBM in general and in the context of parametric instability of two Ion-Bernstein modes by a magnetosonic wave in a multispecies plasma in particular. An improved marginal stability criterion is presented at Local and Global levels and the region where the Orbital effects are influential is defined and discussed. An electron drift relative to the ions is introduced parallel to the external magnetic field giving rise to Current Driven Ion Cyclotron Instability (CDICI). An improved theory of CDICI in a sheared magnetic field is given. For temperature ratios (tau) = T(,i)/T(,e) > .25, the imaginary part of the local dispersion relation, (as a function of k(,(PARLL)) (('x)), the local parallel wavevector), can be approximated by a parabola, while for weaker (tau) it can be approximated by a pair of straight lines; in each case a second order differential equation is solved for complex roots, (omega). Growth rates ((gamma)/(OMEGA)), are plotted against the square of the normalized pependicular wavevector ((TURN)b) for various values of shear, temperature ratios and electron drift strengths. The main effect of shear is to localize this instability in x-space around some x(,0) such that k(,(PARLL))('0) = ('s)k(,y)x(,0), (('s) being inverse shear length), corresponds to the ((gamma)/(OMEGA))(,max) in the absence of shear. Shear also reduces the growth rate in general: however, ((gamma)/(OMEGA)) for the b values away from the value corresponding to the maximum growth rate are affected more than those which are closer, thereby making the instability more coherent in b. Operator methods employing the Vlasov operator to obtain orbits and velocities in external magnetic fields are studied. Particle orbits and

  6. Unstable Electrostatic Ion Cyclotron Waves Exited by an Ion Beam

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens;

    1976-01-01

    Electrostatic ion cyclotron waves were observed in a quiescent cesium plasma into which a low‐energy beam of sodium ions was injected. The instability appeared when the beam velocity was above 12 times the ion thermal velocity. The waves propagated along the magnetic field with a velocity somewhat...

  7. THE DEMINERALIZED WATER SYSTEM FOR THE NRL CYCLOTRON.

    Science.gov (United States)

    handling system was considered impractical to handle this heat load. Therefore, the demineralized water system for the NRL Sector-Focusing Cyclotron...decided to run the water system on a continuous basis. Continuous operation can be dangerous, because it can cause a large leak to occur, but this

  8. Heavy stable isotope separation by ion cyclotron resonance

    Energy Technology Data Exchange (ETDEWEB)

    Louvet, P.; Compant La Fontaine, A.; Larousse, B.; Patris, M.

    1994-12-31

    The scientific feasibility of the ion cyclotron resonance process (ICR), as well as the technical one, has been investigated carefully for light metallic elements, whose masses lies between 40 and 100/1,2/. The present work deals mainly with the same demonstration for heavier elements such as ytterbium, gadolinium and barium. Recent results, as well as future prospects, are considered here. (authors).

  9. Cyclotrons with Fast Variable and/or Multiple Energy Extraction

    CERN Document Server

    Baumgarten, C

    2013-01-01

    We discuss the principle possibility of stripping extraction in combination with reverse bends in isochronous separate sector cyclotrons (and/or FFAGs). If one uses reverse bends between the sectors (instead of drifts) and places stripper foils at the sector exit edges, the stripped beam has a reduced bending radius and it should be able to leave the cyclotron within the range of the reverse bend - even if the beam is stripped at less than full energy. We are especially interested in $H_2^+$-cyclotrons, which allow to double the charge to mass ratio by stripping. However the principle could be applied to other ions or ionized molecules as well. For the production of proton beams by stripping extraction of an $H_2^+$-beam, we discuss possible designs for three types of machines: First a low-energy cyclotron for the simultaneous production of several beams at multiple energies - for instance 15 MeV, 30 MeV and 70 MeV - thus allowing to have beam on several isotope production targets. In this case it is desired ...

  10. Ion-Beam-Excited, Electrostatic, Ion Cyclotron Instability

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1977-01-01

    The stability limits of the ion‐beam‐excited, electrostatic, ion cyclotron instability were investigated in a Q‐machine plasma where the electrons could be heated by microwaves. In agreement with theory, the beam energy necessary for excitation decreased with increasing electron temperature....

  11. Ion-Beam-Excited Electrostatic Ion Cyclotron Instability

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1977-01-01

    The stability limits of the ion‐beam‐excited, electrostatic, ion cyclotron instability were investigated in a Q‐machine plasma where the electrons could be heated by microwaves. In agreement with theory, the beam energy necessary for excitation decreased with increasing electron temperature....

  12. Vacuum Pre-designing for CYCIAE-230 Superconducting Cyclotron

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Su-ping; PAN; Gao-feng; LI; Zhen-guo; QIN; Jiu-chang

    2015-01-01

    CYCIAE-230superconducting cyclotron has two separate vacuum system,one is for beam chamber,another is for cryostat.Beam chamber and cryostat shall maintain separate vacuum against atmospheric pressure.The pressure of pumps inlet is better than 1×10-4Pa and the

  13. Traveling wave ion transport for the cyclotron gas stopper

    Energy Technology Data Exchange (ETDEWEB)

    Brodeur, M., E-mail: maxime.brodeur.2@nd.edu; Joshi, N.; Gehring, A.E.; Bollen, G.; Morrissey, D.J.; Schwarz, S.

    2013-12-15

    Highlights: • Estimated transport time of thermal ions of 5 ms or less for the cyclotron gas stopper using the ion surfing method. • Experimental investigation of a prototype ion conveyor to transport ions in the magnet magnetic field gradient. • Efficient long-distance ion transport with the conveyor is expected. -- Abstract: Next generation beam thermalization devices such as the cyclotron gas stopper are being developed to efficiently deliver a broad range of radioactive isotopes to experiments. Ion transport methods utilizing a traveling wave were investigated experimentally as part of the developments needed for this device. The “ion surfing” method, which will be used to transports thermal ions inside the main chamber of the cyclotron gas stopper, was found to transport ions at speeds reaching 75 m/s, resulting in net transport times as short as 5 ms. A second traveling wave transport method called the “ion conveyor” was investigated for the challenging task of extracting the ions through the cyclotron gas stopper magnetic field gradient. Results from the first prototype conveyor show a strong pressure and wave amplitude dependance for the transport efficiency. A second prototype designed to operate over a larger pressure range is currently being tested.

  14. Cyclotron waves in a non-neutral plasma column

    Energy Technology Data Exchange (ETDEWEB)

    Dubin, Daniel H. E. [Department of Physics, University of California at San Diego, La Jolla, California 92093 (United States)

    2013-04-15

    A kinetic theory of linear electrostatic plasma waves with frequencies near the cyclotron frequency {Omega}{sub c{sub s}} of a given plasma species s is developed for a multispecies non-neutral plasma column with general radial density and electric field profiles. Terms in the perturbed distribution function up to O(1/{Omega}{sub c{sub s}{sup 2}}) are kept, as are the effects of finite cyclotron radius r{sub c} up to O(r{sub c}{sup 2}). At this order, the equilibrium distribution is not Maxwellian if the plasma temperature or rotation frequency is not uniform. For r{sub c}{yields}0, the theory reproduces cold-fluid theory and predicts surface cyclotron waves propagating azimuthally. For finite r{sub c}, the wave equation predicts that the surface wave couples to radially and azimuthally propagating Bernstein waves, at locations where the wave frequency equals the local upper hybrid frequency. The equation also predicts a second set of Bernstein waves that do not couple to the surface wave, and therefore have no effect on the external potential. The wave equation is solved both numerically and analytically in the WKB approximation, and analytic dispersion relations for the waves are obtained. The theory predicts that both types of Bernstein wave are damped at resonances, which are locations where the Doppler-shifted wave frequency matches the local cyclotron frequency as seen in the rotating frame.

  15. Digital control in LLRF system for CYCIAE-100 cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhiguo, E-mail: bitbearAT@hotmail.com; Fu, Xiaoliang; Ji, Bin; Zhang, Tianjue; Wang, Chuan

    2016-05-21

    As a driven accelerator, the CYCIAE-100 cyclotron is designed by China Institute of Atomic Energy for the Beijing Radio Ion-beam Facility project. The cyclotron RF system is designed to use two RF power sources of 100 kW to drive two half-wavelength cavities respectively. Two Dee accelerating electrodes are kept separately from each other inside the cyclotron, while their accelerating voltages are maintained in phase by the efforts of LLRF control. An analog–digital hybrid LLRF system has been developed to achieve cavity tuning control, dee voltage amplitude and phase stabilization etc. The analog subsystems designs are focused on RF signal up/down conversion, tuning control, and dee voltage regulation. The digital system provides an RF signal source, aligns the cavity phases and maintains a Finite State Machine. The digital parts combine with the analog functions to provide the LLRF control. A brief system hardware introduction will be given in this paper, followed by the review of several major characteristics of the digital control in the 100 MeV cyclotron LLRF system. The commissioning is also introduced, and most of the optimization during the process was done by changing the digital parts.

  16. Radiation safety aspects of the AGOR superconducting cyclotron facility

    NARCIS (Netherlands)

    Beijers, JPM; de Meijer, RJ

    1996-01-01

    This paper describes shielding calculations and skyshine estimates for the new AGOR K=600 superconducting cyclotron facility. Both simple, semi-empirical models and Monte-Carlo simulations were used. The calculations are based on a 200 MeV proton beam incident on a trick aluminum target. Also the de

  17. The development of technology for the improvement of cyclotron performance

    Energy Technology Data Exchange (ETDEWEB)

    Chai, Jong Seo; Kim, Y. S.; Ha, J. H.; Lee, M. Y.; Lee, H. S

    1999-05-01

    We show the first-order beam optics theory which is a simplified theory that can be used to carry out the initial design of a cyclotron. Based on this, a computer program has been developed to determine main cyclotron parameters such as number of magnet sectors, sector angle, hill and valley fields, and overall size of the cyclotron etc. We then show the result of two-dimensional magnetic field calculation using POISSON program. By using this program, one can determine magnet yoke geometry and the average magnetic fields etc. Finally, the three-dimensional computer program OPERA-3D had been invoked to determine magnet pole tips (i.e. sector). Validity of the design can be seen by investigating magnetic fields, radial and vertical focusing frequencies as a function of the beam energy. In this report, we show the results of cyclotron magnet design. And we designed 72 MHz RF system and ion source system. We tested RF resonance each coupling methods. We show the result of RF design and prototype operation. Our developed ion source is PIG type. We described our design methods and implementation. We report the result of getting negative hydrogen ion.

  18. Fokker-Planck Study of Tokamak Electron Cyclotron Resonance Heating

    Institute of Scientific and Technical Information of China (English)

    SHIBingren; LONGYongxing; DONGJiaqi; LIWenzhong; JIAOYiming; WANGAike

    2002-01-01

    In this study, we add a subroutine for describing the electron cyclotron resonant heating calculation to the Fokker-Planck code. By analyzing the wave-particle resonance condition in tokamak plasma and the fast motion of electrons along magnetic field lines, suitable quasi-linear diffusion coefficients are given.

  19. Development of beam instruments at JAERI cyclotron facility

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, Susumu; Fukuda, Mitsuhiro; Ishibori, Ikuo; Agematsu, Takashi; Yokota, Watalu; Nara, Takayuki; Nakamura, Yoshiteru; Arakawa, Kazuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    A beam phase monitor and two kinds of fluence distribution monitors have been developed for measuring characteristics of cyclotron beams. The beam phase monitor provides a beam phase signal for tuning a beam chopping system and a beam phase selection system. A two-dimensional fluence distribution on a large area is measured with fluence distribution monitors. (author)

  20. Electron cyclotron heating and current drive in toroidal geometry

    Energy Technology Data Exchange (ETDEWEB)

    Kritz, A.H.

    1991-11-01

    The Principal Investigator has continued to work on problems associated both with the deposition and with the emission of electron cyclotron power in toroidal plasmas. We have investigated the use of electron cyclotron resonance heating for bringing compact tokamaks (BPX) to ignition-like parameters. This requires that we continue to refine the modeling capability of the TORCH code linked with the BALDUR 1 {1/2} D transport code. Using this computational tool, we have examined the dependence of ignition on heating and transport employing both theoretical (multi-mode) and empirically based transport models. The work on current drive focused on the suppression of tearing modes near the q = 2 surface and sawteeth near the q = 1 surface. Electron cyclotron current drive in CIT near the q =2 surface was evaluated for a launch scenario where electron cyclotron power was launched near the equatorial plane. The work on suppression of sawteeth has been oriented toward understanding the suppression that has been observed in a number of tokamaks, in particular, in the WT-3 tokamak in Kyoto. To evaluate the changes in current profile (shear) near the q =1 surface, simulations have been carried out using the linked BALDUR-TORCH code. We consider effects on shear resulting both from wave-induced current as well as from changes in conductivity associated with changes in local temperature. Abstracts and a paper relating to this work is included in Appendix A.

  1. Maryland University sectored isochronous cyclotron (MUSIC): Progress report No. 35

    Energy Technology Data Exchange (ETDEWEB)

    1986-10-29

    Efforts are reported on the installation and checkout of cyclotron components which had been previously fabricated. Final integration of subsystems and major systems leading to internal beam tests is reported near completion. Progress is reported in relation to control system components, focus and steering magnet design, and rf system testing. (LEW)

  2. Digital control in LLRF system for CYCIAE-100 cyclotron

    Science.gov (United States)

    Yin, Zhiguo; Fu, Xiaoliang; Ji, Bin; Zhang, Tianjue; Wang, Chuan

    2016-05-01

    As a driven accelerator, the CYCIAE-100 cyclotron is designed by China Institute of Atomic Energy for the Beijing Radio Ion-beam Facility project. The cyclotron RF system is designed to use two RF power sources of 100 kW to drive two half-wavelength cavities respectively. Two Dee accelerating electrodes are kept separately from each other inside the cyclotron, while their accelerating voltages are maintained in phase by the efforts of LLRF control. An analog-digital hybrid LLRF system has been developed to achieve cavity tuning control, dee voltage amplitude and phase stabilization etc. The analog subsystems designs are focused on RF signal up/down conversion, tuning control, and dee voltage regulation. The digital system provides an RF signal source, aligns the cavity phases and maintains a Finite State Machine. The digital parts combine with the analog functions to provide the LLRF control. A brief system hardware introduction will be given in this paper, followed by the review of several major characteristics of the digital control in the 100 MeV cyclotron LLRF system. The commissioning is also introduced, and most of the optimization during the process was done by changing the digital parts.

  3. Effect of Quantizing Magnetic Field on Cyclotron Energy and Cyclotron Effective Mass in Size Quantized Films with Non-Parabolic Energy Band

    Institute of Scientific and Technical Information of China (English)

    B.(I). GUL(I)YEV; R. F. EM(I)NBEYL(I); A. KORKUT

    2007-01-01

    The Fermi energy, cyclotron energy and cyclotron effective mass of degenerate electron gas in a size-quantized semiconductor thin film with non-parabolic energy bands are studied. The influences of quantizing magnetic field on these quantities in two-band approximation of the Kane model are investigated. It is shown that the Fermi energy oscillates in a magnetic field. The period and positions of these oscillations are found as a function of film thickness and concentration of electrons. Cyclotron energy and cyclotron effective mass are investigated as a function of film thickness in detail. The results obtained here are compared with experimental data on GaAs quantum wells.

  4. Heavy ion cocktail beams at the 88 inch Cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Leitner, Daniela; McMahan, Margaret A.; Argento, David; Gimpel, Thomas; Guy, Aran; Morel, James; Siero, Christine; Thatcher, Ray; Lyneis, Claude M.

    2002-09-03

    Cyclotrons in combination with ECR ion sources provide the ability to accelerate ''cocktails'' of ions. A cocktail is a mixture of ions of near-identical mass-to-charge (m/q) ratio. The different ions cannot be separated by the injector mass-analyzing magnet and are tuned out of the ion source together. The cyclotron then is utilized as a mass analyzer by shifting the accelerating frequency. This concept was developed soon after the first ECR ion source became operational at the 88-Inch Cyclotron and has since become a powerful tool in the field of heavy ion radiation effects testing. Several different ''cocktails'' at various energies are available at the 88-Inch cyclotron for radiation effect testing, covering a broad range of linear energy transfer and penetration depth. Two standard heavy ion cocktails at 4.5 MeV/nucleon and 10 MeV/nucleon have been developed over the years containing ions from boron to bismuth. Recently, following requests for higher penetration depths, a 15MeV/nucleon heavy ion cocktail has been developed. Up to nine different metal and gaseous ion beams at low to very high charge states are tuned out of the ion source simultaneously and injected together into the cyclotron. It is therefore crucial to balance the ion source very carefully to provide sufficient intensities throughout the cocktail. The paper describes the set-up and tuning of the ion source for the various heavy ion cocktails.

  5. Alternative energies; Energies alternatives

    Energy Technology Data Exchange (ETDEWEB)

    Bonal, J.; Rossetti, P

    2007-07-01

    The earth took millions years to made the petroleum, the gas the coal and the uranium. Only a few centuries will be needed to exhaust these fossil fuels and some years to reach expensive prices. Will the wold continue on this way of energy compulsive consumption? The renewable energies and some citizen attitudes are sufficient to break this spiral. This book proposes to discuss these alternative energies. It shows that this attitude must be supported by the government. It takes stock on the more recent information concerning the renewable energies. it develops three main points: the electricity storage, the housing and the transports. (A.L.B.)

  6. On-line optimal control of greenhouse crop cultivation.

    NARCIS (Netherlands)

    Straten, van G.

    1996-01-01

    Thus far, optimal control has primarily been investigated for seasonal crop growth optimization. On-line aspects have received much less attention. The decomposition between long term strategies and on-line control, however, is not trivial. Appreciable losses occur when set-points generated by seaso

  7. ON-LINE PREEMPTIVE SCHEDULING ON UNIFORM MACHINES

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yuzhong; WANG Shouyang; Bo Chen; ZHANG Shuxia

    2001-01-01

    We address the problem of preemptively schedule on-line jobs on arbitrary muniformly related machines with the objective of minimizing the schedule length. We provide the first on-line algorithm for this general problem, and show that the algorithm being the speeds of the m machines.

  8. From Off-line to On-line Handwriting Recognition

    NARCIS (Netherlands)

    Lallican, P.; Viard-Gaudin, C.; Knerr, S.

    2004-01-01

    On-line handwriting includes more information on time order of the writing signal and on the dynamics of the writing process than off-line handwriting. Therefore, on-line recognition systems achieve higher recognition rates. This can be concluded from results reported in the literature, and has been

  9. On-Line and Off-Line Assessment of Metacognition

    Science.gov (United States)

    Saraç, Seda; Karakelle, Sema

    2012-01-01

    The study investigates the interrelationships between different on-line and off-line measures for assessing metacognition. The participants were 47 fifth grade elementary students. Metacognition was assessed through two off-line and two on-line measures. The off-line measures consisted of a teacher rating scale and a self-report questionnaire. The…

  10. Algorithms for semi on-line multiprocessor scheduling problems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the classical multiprocessor scheduling problems, it is assumed that the problems are considered in off-line or on-line environment. But in practice, problems are often not really off-line or on-line but somehow in between. This means that, with respect to the on-line problem, some further information about the tasks is available, which allows the improvement of the performance of the best possible algorithms. Problems of this class are called semi on-line ones. The authors studied two semi on-line multiprocessor scheduling problems, in which, the total processing time of all tasks is known in advance, or all processing times lie in a given interval. They proposed approximation algorithms for minimizing the makespan and analyzed their performance guarantee. The algorithms improve the known results for 3 or more processor cases in the literature.

  11. Alternative additives; Alternative additiver

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-15

    In this project a number of industrial and agricultural waste products have been characterised and evaluated in terms of alkali-getter performance. The intended use is for biomass-fired power stations aiming at reducing corrosion or slagging related problems. The following products have been obtained, characterised and evaluated: 1) Brewery draff 2) Danish de-gassed manure 3) Paper sludge 4) Moulding sand 5) Spent bleaching earth 6) Anorthosite 7) Sand 8) Clay-sludge. Most of the above alternative additive candidates are deemed unsuitable due to insufficient chemical effect and/or expensive requirements for pre-treatment (such as drying and transportation). 3 products were selected for full-scale testing: de-gassed manure, spent bleaching earth and clay slugde. The full scale tests were undertaken at the biomass-fired power stations in Koege, Slagelse and Ensted. Spent bleaching earth (SBE) and clay sludge were the only tested additive candidates that had a proven ability to react with KCl, to thereby reduce Cl-concentrations in deposits, and reduce the deposit flux to superheater tubes. Their performance was shown to nearly as good as commercial additives. De-gassed manure, however, did not evaluate positively due to inhibiting effects of Ca in the manure. Furthermore, de-gassed manure has a high concentration of heavy metals, which imposes a financial burden with regard to proper disposal of the ash by-products. Clay-sludge is a wet clay slurring, and drying and transportation of this product entails substantial costs. Spent bleaching does not require much pre-treatment and is therefore the most promising alternative additive. On the other hand, bleaching earth contains residual plant oil which means that a range of legislation relating to waste combustion comes into play. Not least a waste combustion fee of 330 DKK/tonne. For all alternative (and commercial) additives disposal costs of the increase ash by-products represents a significant cost. This is

  12. Improved charge breeding efficiency of light ions with an electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Vondrasek, R.; Kutsaev, Sergey [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Delahaye, P.; Maunoury, L. [Grand Accelerateur National d' Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Blvd Henri Becquerel, 14076 Caen (France)

    2012-11-15

    The Californium Rare Isotope Breeder Upgrade is a new radioactive beam facility for the Argonne Tandem Linac Accelerator System (ATLAS). The facility utilizes a {sup 252}Cf fission source coupled with an electron cyclotron resonance ion source to provide radioactive beam species for the ATLAS experimental program. The californium fission fragment distribution provides nuclei in the mid-mass range which are difficult to extract from production targets using the isotope separation on line technique and are not well populated by low-energy fission of uranium. To date the charge breeding program has focused on optimizing these mid-mass beams, achieving high charge breeding efficiencies of both gaseous and solid species including 14.7% for the radioactive species {sup 143}Ba{sup 27+}. In an effort to better understand the charge breeding mechanism, we have recently focused on the low-mass species sodium and potassium which up to present have been difficult to charge breed efficiently. Unprecedented charge breeding efficiencies of 10.1% for {sup 23}Na{sup 7+} and 17.9% for {sup 39}K{sup 10+} were obtained injecting stable Na{sup +} and K{sup +} beams from a surface ionization source.

  13. Summary of EC-17: the 17th Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating (Deurne, The Netherlands, 7-10 May 2012)

    NARCIS (Netherlands)

    Westerhof, E.; Austin, M. E.; Kubo, S.; Lin-Liu, Y. R.; Plaum, B.

    2013-01-01

    An overview is given of the papers presented at the 17th Joint Workshop on Electron Cyclotron Emission (ECE) and Electron Cyclotron Resonance Heating (ECRH). The meeting covered all aspects of the research field ranging from theory to enabling technologies. From the workshop, advanced control by ele

  14. Understanding on-line community: the affordances of virtual space

    Directory of Open Access Journals (Sweden)

    Karen Ruhleder

    2002-01-01

    Full Text Available Increasing numbers of on-line venues for learning are emerging as virtual communities become more accessible and commonplace. This paper looks at one particular virtual community, an on-line degree programme at the University of Illinois, Urbana-Champaign, which offers an M.S. in Library and Information Science (called LEEP. It draws on a framework presented by Mynatt, et al. (1998, which provides a lens for talking about on-line community as a set of affordances. This framework is applied to illustrate the interactions, artefacts, and expectations that shape this community.

  15. On-line Classical Guitar Course: Blogs for Music Education

    OpenAIRE

    José Luis Navarro; Gilles Lavigne; G. Guadalupe Martínez Salgado

    2009-01-01

    This article introduces an on-line course constructed by means of a blog. The tool was the main goal of a research project titled “Develop, Implementation and evaluation of a Hybrid Course Face to face-On Line for Teaching the Beginning to Play the Classical Guitar”. This work was a three steep project in which it was implemented, applied and evaluated. The on-line course was intended to prepare the students to learn the basic principles to start in classical music with the guitar. The result...

  16. On-line Autonomous Learning Based on Leamerg Expectation

    Institute of Scientific and Technical Information of China (English)

    李利娜

    2008-01-01

    On-line autonomous learning of College English is one of the important reforms in colleges recently.This paper aims to explore the changes of teachers'role in the new on-line setting.The article first reviews the theoretical study of learner autonomy,then makes a practical investigation into the attitude and expectation learners have on teachers through a self-designed questionnaire,and explores that teachers should make an adjustment to their role orientation and changes their roles into motivators,evaluators and resources supphers in the new on-line setting.

  17. Cyclotron resonance studies on InAs/GaSb heterostructures

    CERN Document Server

    Petchsingh, C

    2002-01-01

    Far-infrared cyclotron resonance is used to study the magneto-optical properties of semimetallic InAs/GaSb heterostructures. Spatially separated two-dimensional electron and hole gases coexist in this 'broken-gap' type-ll system due to charge transfer across the interfaces. Hybridisations of the overlapping electron and hole wavefunctions are investigated experimentally in samples of varying growth parameters. A self-consistent 8-band k centre dot p model is used to assist in the interpretation of experimental results. In samples subjected to varying magnetic field, hybridisations result in oscillations of cyclotron resonance mass, amplitude and linewidth, accompanied by transition splittings in the vicinity of Landau level anticrossings. Asymmetries introduced by InSb interface biasing enhance these effects. Comparison of samples with varying confinement energies (at specified magnetic field) shows effective mass enhancement greater than the standard nonparabolicity effect. The mass enhancement increases wit...

  18. Studies of radioisotope production with an AVF cyclotron in TIARA

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, Toshiaki [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    The production of radioisotopes to be used mainly for nuclear medicine and biology is studied with an AVF cyclotron in TIARA. A production method of no-carrier-added {sup 186}Re with the {sup 186}W(p,n){sup 186}Re reaction has been developed; this product may be used as a therapeutic agent in radioimmunotherapy due to the adequate nuclear and chemical properties. For the study of the function of plants using a positron-emitter two-dimensional imaging system, a simple method of producing the positron emitter {sup 18}F in water was developed by taking advantage of a highly-energetic {alpha} beam from the AVF cyclotron. (author)

  19. Physics of electron cyclotron current drive on DIII-D

    CERN Document Server

    Petty, C C; Harvey, R W; Kinsey, J E; Lao, L L; Lohr, J; Luce, T C; Makowski, M A; Prater, R

    2002-01-01

    OAK A271 PHYSICS OF ELECTRON CYCLOTRON CURRENT DRIVE ON DIII-D. Recent experiments on the DIII-D tokamak have focused on determining the effect of trapped particles on the electron cyclotron current drive (ECCD) efficiency. The measured ECCD efficiency increases as the deposition location is moved towards the inboard midplane or towards smaller minor radius for both co and counter injection. The measured ECCD efficiency also increases with increasing electron density and/or temperature. The experimental ECCD is compared to both the linear theory (Toray-GA) as well as a quasilinear Fokker-Planck model (CQL3D). The experimental ECCD is found to be in better agreement with the more complete Fokker-Planck calculation, especially for cases of high rf power density and/or loop voltage. The narrow width of the measured ECCD profile is consistent with only low levels of radial transport for the current carrying electrons.

  20. Ernest Orlando Lawrence (1901-1958), Cyclotron and Medicine

    Energy Technology Data Exchange (ETDEWEB)

    Chu, William T.

    2005-09-01

    On August 8, 2001, Lawrence Berkeley National Laboratory celebrated the centennial of the birth of its founder (and namesake), Ernest Orlando Lawrence. For the occasion, many speeches were given and old speeches were remembered. We recall the words of the late Luis Alvarez, a Nobel Laureate and one of the Lawrence's closest colleagues: ''Lawrence will always be remembered as the inventor of the cyclotron, but more importantly, he should be remembered as the inventor of the modern way of doing science''. J. L. Heilbron and R. W. Seidel, in the introduction of their book, ''Lawrence and His Laboratory'' stated, ''The motives and mechanisms that shaped the growth of the Laboratory helped to force deep changes in the scientific estate and in the wider society. In the entrepreneurship of its founder, Ernest Orlando Lawrence, these motives, mechanisms, and changes came together in a tight focus. He mobilized great and small philanthropists, state and local governments, corporations, and plutocrats, volunteers and virtuosos. The work they supported, from astrophysics and atomic bombs, from radiochemistry to nuclear medicine, shaped the way we observe, control, and manipulate our environment.'' Indeed, all over the civilized world, the ways we do science changed forever after Lawrence built his famed Radiation Laboratory. In this editorial, we epitomize his legacy of changing the way we do medicine, thereby affecting the health and well being of all humanity. This year marks the 75th anniversary of the invention of the cyclotron by Ernest Orlando Lawrence at the University of California at Berkeley. Lawrence conceived the idea of the cyclotron early in 1929 after reading an article by Rolf Wideroe on high-energy accelerators. In the spring of 1930 one of his students, Nels Edlefsen, constructed two crude models of a cyclotron. Later in the fall of the same year, another student, M. Stanley Livingston

  1. RF cavity design for KIRAMS-430 superconducting cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Jung, In Su, E-mail: jis@kirams.re.kr [Korea Institute of Radiological & Medical Sciences (KIRMAS), 75 Nowon-Gil, Nowon-Gu, Seoul 139-706 (Korea, Republic of); Hong, Bong Hwan; Kang, Joonsun; Kim, Hyun Wook; Kim, Chang Hyeuk [Korea Institute of Radiological & Medical Sciences (KIRMAS), 75 Nowon-Gil, Nowon-Gu, Seoul 139-706 (Korea, Republic of); Kwon, Key Ho [School of Information and Communication Engineering, Natural Sciences Campus, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2015-03-21

    The Korea Heavy Ion Medical Accelerator (KHIMA) has developed a superconducting cyclotron for the carbon therapy, which is called KIRAMS-430. The cyclotron is designed to accelerate only {sup 12}C{sup 6+} ions up to the energy of 430 MeV/u. It uses two normal conducting RF cavities. The RF frequency is about 70.76 MHz. The nominal dee voltage is 70 kV at the center and 160 kV at the extraction. The RF cavity was designed with 4 stems by using CST microwave studio (MWS). In this paper, we represent the simulation results and the optimized design of the RF cavity for the KIRAMS-430.

  2. Vortex dynamics and shear layer instability in high intensity cyclotrons

    CERN Document Server

    Cerfon, Antoine J

    2016-01-01

    We show that the space charge dynamics of high intensity beams in the plane perpendicular to the magnetic field in cyclotrons is described by the two-dimensional Euler equations for an incompressible fluid. This analogy with fluid dynamics gives a unified and intuitive framework to explain the beam spiraling and beam break up behavior observed in experiments and in simulations. In particular, we demonstrate that beam break up is the result of a classical instability occurring in fluids subject to a sheared flow. We give scaling laws for the instability and predict the nonlinear evolution of beams subject to it. Our work suggests that cyclotrons may be uniquely suited for the experimental study of shear layers and vortex distributions that are not achievable in Penning-Malmberg traps.

  3. Examination of the Plasma located in PSI Ring Cyclotron

    CERN Document Server

    Pogue, Nathaniel; Schneider, Markus; Stingelin, Lukas

    2016-01-01

    A plasma has been observed inside the vacuum chamber of the PSI Ring Cyclotron. This ionized gas cloud maybe a substantial contributor to several interior components having reduced lifetimes. The plasma's generation has been directly linked to the voltage that is applied to the Flat Top Cavity through visual confirmation using CCD cameras. A spectrometer was used to correlate the plasma's intensity and ignition to the Flat Top Cavity voltage as well as to determine the composition of the plasma. This paper reports on the analysis of the plasma using spectroscopy. The spectrometer data was analyzed to determine the composition of the plasma and that the plasma intensity (luminosity) directly corresponds to the Flat Top voltage. The results showed that the plasma was comprised of elements consistent with the cyclotrons vacuum interior

  4. Activity-Based Costing Models for Alternative Modes of Delivering On-Line Courses

    Science.gov (United States)

    Garbett, Chris

    2011-01-01

    In recent years there has been growth in online distance learning courses. This has been prompted by; new technology such as the Internet, mobile learning, video and audio conferencing: the explosion in student numbers in Higher Education, and the need for outreach to a world wide market. Web-based distance learning is seen as a solution to…

  5. Heavy ion beam transmission in the AGOR cyclotron

    NARCIS (Netherlands)

    Sen, Ayanangsha

    2013-01-01

    In the framework of the TRImP program initiated at the KVI in 2002, the AGOR cyclotron was used to accelerate low energy heavy ion beams up to a beam intensity (>=10^12 particles per second). Typical beam ions are: 206Pb accelerated to 8 MeV/amu and 20Ne accelerated to 25 MeV/amu. In the course of b

  6. Design options for an ITER ion cyclotron system

    Science.gov (United States)

    Swain, D. W.; Baity, F. W.; Bigelow, T. S.; Ryan, P. M.; Goulding, R. H.; Carter, M. D.; Stallings, D. C.; Batchelor, D. B.; Hoffman, D. J.

    1996-02-01

    Recent changes have occurred in the design requirements for the ITER ion cyclotron system, requiring in-port launchers in four main horizontal ports to deliver 50 MW of power to the plasma. The design is complicated by the comparatively large antenna-separatrix distance of 10-20 cm. Designs of a conventional strap launcher and a folded waveguide launcher that can meet the new requirements are presented.

  7. Design options for an ITER ion cyclotron system

    Energy Technology Data Exchange (ETDEWEB)

    Swain, D.W.; Baity, F.W.; Bigelow, T.S.; Ryan, P.M.; Goulding, R.H.; Carter, M.D.; Stallings, D.C.; Batchelor, D.B.; Hoffman, D.J. [Oak Ridge National Laboratory, P.O. Box 2009, Oak Ridge, Tennessee 37831 (United States)

    1996-02-01

    Recent changes have occurred in the design requirements for the ITER ion cyclotron system, requiring in-port launchers in four main horizontal ports to deliver 50 MW of power to the plasma. The design is complicated by the comparatively large antenna-separatrix distance of 10{endash}20 cm. Designs of a conventional strap launcher and a folded waveguide launcher that can meet the new requirements are presented. {copyright} {ital 1996 American Institute of Physics.}

  8. Design options for an ITER ion cyclotron system

    Energy Technology Data Exchange (ETDEWEB)

    Swain, D.W.; Baity, F.W.; Bigelow, T.S.; Ryan, P.M.; Goulding, R.H.; Carter, M.D.; Stallings, D.C.; Batchelor, D.B.; Hoffman, D.J.

    1995-09-01

    Recent changes have occurred in the design requirements for the ITER ion cyclotron system, requiring in-port launchers in four main horizontal ports to deliver 50 MW of power to the plasma. The design is complicated by the comparatively large antenna-separatrix distance of 10--20 cm. Designs of a conventional strap launcher and a folded waveguide launcher than can meet the new requirements are presented.

  9. Multimegawatt DAE$\\delta$ALUS Cyclotrons for Neutrino Physics

    CERN Document Server

    Abs, M; Alonso, J R; Barletta, W A; Barlow, R; Calabretta, L; Calanna, A; Campo, D; Celona, L; Conrad, J M; Gammino, S; Kleeven, W; Koeth, T; Maggiore, M; Okuno, H; Piazza, L A C; Seidel, M; Shaevitz, M H; Stingelin, L; Yang, J J; Yeck, J

    2012-01-01

    DAE$\\delta$ALUS (Decay-At-rest Experiment for $\\delta_{CP}$ studies At the Laboratory for Underground Science) provides a new approach to the search for CP violation in the neutrino sector. High-power continuous-wave proton cyclotrons efficiently provide the necessary proton beams with an energy of up to 800 MeV to create neutrinos from pion and muon decay-at-rest. The experiment searches for $\\bar{\

  10. Development of Production Procedure of 64Cu on Cyclotron

    Institute of Scientific and Technical Information of China (English)

    LIANG; Ji-xin; CHEN; Yu-qing; LI; Guang; DENG; Xue-song; SHEN; Yi-jia; QIAO; Lai-cheng; LIU; Yu-ping; JIANG; Hua; LI; Gui-qun

    2013-01-01

    Due to intermediate half-life(12.7 h)and favourable coordination chemistry,64Cu is an important emerging medical radionuclide that is suitable for labeling a wide range of radiopharmaceuticals for PET imaging and radiotherapy of tumor.The aim of this study is to develop the procedure for 64Cu production on Cyclone-30 cyclotron providing energy from 15-30 MeV.

  11. Electron Cyclotron Waves Polarization in the TJII Stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Cappa, A.; Martinez-Fernandez, J.; Wagner, D.

    2013-05-01

    This report describes the theoretical calculations related with the electron cyclotron (EC) waves polarization control in the TJII stellarator. Two main aspects will be distinguished: the determination of the vacuum polarization that the wave must exhibit if a given propagation mode in a cold plasma is desired and the calculation of the behavior of the grooved polarizers and other transmission systems used to launch the vacuum wave with the required polarization. (Author) 13 refs.

  12. Coaxial Ring Cyclotron as a Perspective Nuclear Power Engineering Machine

    OpenAIRE

    Tumanyan, A. R.; Simonyan, Kh. A.; Mkrtchyan, R. L.; Amatuni, A. Ts.; Avakyan, R. O.; Khudaverdyan, A. G.

    1995-01-01

    The circuit arrangement of the proposed coaxial ring cyclotron (CRC) is described, and its main advantages, such as simple injection technique, several injected beams summation option, high efficiency, are considered. The proposed proton accelerator is a perspective machine for the solution of the main problems of the present day nuclear power engineering as well as for the next-generation nuclear power plants, representing a combination of subcritical reactors and particle accelerators. The ...

  13. The cyclotron laboratory and the RFQ accelerator in Bern

    Science.gov (United States)

    Braccini, S.; Ereditato, A.; Kreslo, I.; Nirkko, M.; Scampoli, P.; von Bremen, K.; Weber, M.

    2013-07-01

    Two proton accelerators have been recently put in operation in Bern: an 18 MeV cyclotron and a 2 MeV RFQ linac. The commercial IBA 18/18 cyclotron, equipped with a specifically conceived 6 m long external beam line ending in a separate bunker, will provide beams for routine 18-F and other PET radioisotope production as well as for novel detector, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. The accelerator is embedded into a complex building hosting two physics laboratories and four Good Manufacturing Practice (GMP) laboratories. This project is the result of a successful collaboration between the Inselspital, the University of Bern and private investors, aiming at the constitution of a combined medical and research centre able to provide the most cutting-edge technologies in medical imaging and cancer radiation therapy. The cyclotron is complemented by the RFQ with the primary goals of elemental analysis via Particle Induced Gamma Emission (PIGE), and the detection of potentially dangerous materials with high nitrogen content using the Gamma-Resonant Nuclear Absorption (GRNA) technique. In this context, beam instrumentation devices have been developed, in particular an innovative beam profile monitor based on doped silica fibres and a setup for emittance measurements using the pepper-pot technique. On this basis, the establishment of a proton therapy centre on the campus of the Inselspital is in the phase of advanced study.

  14. The cyclotron laboratory and the RFQ accelerator in Bern

    Energy Technology Data Exchange (ETDEWEB)

    Braccini, S.; Ereditato, A.; Kreslo, I.; Nirkko, M.; Weber, M. [Albert Einstein Center for Fundamental Physics, Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern (Switzerland); Scampoli, P. [Albert Einstein Center for Fundamental Physics, Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland and Department of Physical Sciences, University Federico II, Via Cintia, I-60126 Napoli (Italy); Bremen, K. von [SWAN Isotopen AG, Inselspital, CH-3010 Bern (Switzerland)

    2013-07-18

    Two proton accelerators have been recently put in operation in Bern: an 18 MeV cyclotron and a 2 MeV RFQ linac. The commercial IBA 18/18 cyclotron, equipped with a specifically conceived 6 m long external beam line ending in a separate bunker, will provide beams for routine 18-F and other PET radioisotope production as well as for novel detector, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. The accelerator is embedded into a complex building hosting two physics laboratories and four Good Manufacturing Practice (GMP) laboratories. This project is the result of a successful collaboration between the Inselspital, the University of Bern and private investors, aiming at the constitution of a combined medical and research centre able to provide the most cutting-edge technologies in medical imaging and cancer radiation therapy. The cyclotron is complemented by the RFQ with the primary goals of elemental analysis via Particle Induced Gamma Emission (PIGE), and the detection of potentially dangerous materials with high nitrogen content using the Gamma-Resonant Nuclear Absorption (GRNA) technique. In this context, beam instrumentation devices have been developed, in particular an innovative beam profile monitor based on doped silica fibres and a setup for emittance measurements using the pepper-pot technique. On this basis, the establishment of a proton therapy centre on the campus of the Inselspital is in the phase of advanced study.

  15. Modern compact accelerators of cyclotron type for medical applications

    Science.gov (United States)

    Smirnov, V.; Vorozhtsov, S.

    2016-09-01

    Ion beam therapy and hadron therapy are types of external beam radiotherapy. Recently, the vast majority of patients have been treated with protons and carbon ions. Typically, the types of accelerators used for therapy were cyclotrons and synchrocyclotrons. It is intuitively clear that a compact facility fits best to a hospital environment intended for particle therapy and medical diagnostics. Another criterion for selection of accelerators to be mentioned in this article is application of superconducting technology to the magnetic system design of the facility. Compact isochronous cyclotrons, which accelerate protons in the energy range 9-30 MeV, have been widely used for production of radionuclides. Energy of 230 MeV has become canonical for all proton therapy accelerators. Similar application of a carbon beam requires ion energy of 430 MeV/u. Due to application of superconducting coils the magnetic field in these machines can reach 4-5 T and even 9 T in some cases. Medical cyclotrons with an ironless or nearly ironless magnetic system that have a number of advantages over the classical accelerators are in the development stage. In this work an attempt is made to describe some conceptual and technical features of modern accelerators under consideration. The emphasis is placed on the magnetic and acceleration systems along with the beam extraction unit, which are very important from the point of view of the facility compactness and compliance with the strict medical requirements.

  16. RF control hardware design for CYCIAE-100 cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhiguo, E-mail: bitbearAT@hotmail.com; Fu, Xiaoliang; Ji, Bin; Zhao, Zhenlu; Zhang, Tianjue; Li, Pengzhan; Wei, Junyi; Xing, Jiansheng; Wang, Chuan

    2015-11-21

    The Beijing Radioactive Ion-beam Facility project is being constructed by BRIF division of China Institute of Atomic Energy. In this project, a 100 MeV high intensity compact proton cyclotron is built for multiple applications. The first successful beam extraction of CYCIAE-100 cyclotron was done in the middle of 2014. The extracted proton beam energy is 100 MeV and the beam current is more than 20 μA. The RF system of the CYCIAE-100 cyclotron includes two half-wavelength cavities, two 100 kW tetrode amplifiers and power transmission line systems (all above are independent from each other) and two sets of Low Level RF control crates. Each set of LLRF control includes an amplitude control unit, a tuning control unit, a phase control unit, a local Digital Signal Process control unit and an Advanced RISC Machines based EPICS IOC unit. These two identical LLRF control crates share one common reference clock and take advantages of modern digital technologies (e.g. DSP and Direct Digital Synthesizer) to achieve closed loop voltage and phase regulations of the dee-voltage. In the beam commission, the measured dee-voltage stability of RF system is better than 0.1% and phase stability is better than 0.03°. The hardware design of the LLRF system will be reviewed in this paper.

  17. Emittance Measurement for Beamline Extension at the PET Cyclotron

    Directory of Open Access Journals (Sweden)

    Sae-Hoon Park

    2016-01-01

    Full Text Available Particle-induced X-ray emission is used for determining the elemental composition of materials. This method uses low-energy protons (of several MeV, which can be obtained from high-energy (of tens MeV accelerators. Instead of manufacturing an accelerator for generating the MeV protons, the use of a PET cyclotron has been suggested for designing the beamline for multipurpose applications, especially for the PIXE experiment, which has a dedicated high-energy (of tens MeV accelerator. The beam properties of the cyclotron were determined at this experimental facility by using an external beamline before transferring the ion beam to the experimental chamber. We measured the beam profile and calculated the emittance using the pepper-pot method. The beam profile was measured as the beam current using a wire scanner, and the emittance was measured as the beam distribution at the beam dump using a radiochromic film. We analyzed the measurement results and are planning to use the results obtained in the simulations of external beamline and aligned beamline components. We will consider energy degradation after computing the beamline simulation. The experimental study focused on measuring the emittance from the cyclotron, and the results of this study are presented in this paper.

  18. Ion cyclotron resonance detection techniques at TRIGA-TRAP

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, K.; Eberhardt, K.; Ketelaer, J. [Johannes Gutenberg-Universitaet, Mainz (Germany); Beyer, T.; Blaum, K. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Ruprecht-Karls-Universitaet, Heidelberg (Germany); Block, M.; Herfurth, F. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Eibach, M.; Smorra, C. [Johannes Gutenberg-Universitaet, Mainz (Germany); Ruprecht-Karls-Universitaet, Heidelberg (Germany); Nagy, S. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)

    2010-07-01

    In Penning trap mass spectrometry the mass of stored ions is obtained via a determination of the cyclotron frequency ({nu}{sub c}=qB/(2 {pi} m)), for which two different techniques are available. The destructive time-of-flight ion cyclotron resonance (TOF-ICR) technique, based on the measurement of the flight time of excited ions, is the established method for measurements on short-lived radionuclides. It is not ideally suited for rarely produced ion species, since typically some hundred ions are required for a single resonance spectrum. At the Penning trap mass spectrometer TRIGA-TRAP therefore a non-destructive narrow-band Fourier transform ion cyclotron resonance (FT-ICR) detection system is being developed. It is based on the detection of the image currents induced by the stored ions in the trap electrodes and will ultimately reach single ion sensitivity. TRIGA-TRAP also features broad-band FT-ICR detection for the coarse identification of the trap content. Additionally, the TOF-ICR detection system has been recently improved to utilize the Ramsey excitation technique to gain in precision, and the position information of the ion impact to further suppress background events in the final time-of-flight spectrum.

  19. An On-line Ferrograph for Monitoring Machine Wear

    Institute of Scientific and Technical Information of China (English)

    L(U) Xiao-jun; JING Min-qing; XIE You-bai

    2005-01-01

    In order to improve an on-line ferrograph, this paper simulates a three dimensional magnetic field distribution of an electromagnet, builds a sinking motion model of a wear particle, and investigates the motion law of wear particles under two different conditions. Both numeric results and experimental results show that the on-line ferrograph is capable of monitoring machine wear conditions by measuring the concentration and size distribution of wear particles in lubricating oil.

  20. From User Comments to On-line Conversations

    OpenAIRE

    Wang, Chunyan; Ye, Mao; Huberman, Bernardo A.

    2012-01-01

    We present an analysis of user conversations in on-line social media and their evolution over time. We propose a dynamic model that accurately predicts the growth dynamics and structural properties of conversation threads. The model successfully reconciles the differing observations that have been reported in existing studies. By separating artificial factors from user behaviors, we show that there are actually underlying rules in common for on-line conversations in different social media web...

  1. ON-LINE SCHEDULING WITH REJECTION ON IDENTICAL PARALLEL MACHINES

    Institute of Scientific and Technical Information of China (English)

    Cuixia MIAO; Yuzhong ZHANG

    2006-01-01

    In this paper, we consider the on-line scheduling of unit time jobs with rejection on m identical parallel machines. The objective is to minimize the total completion time of the accepted jobs plus the total penalty of the rejected jobs. We give an on-line algorithm for the problem with competitive ratio 1/2(2 + √3) ≈ 1.86602.

  2. The cyclotron maser theory of AKR and Z-mode radiation. [Auroral Kilometric Radiation

    Science.gov (United States)

    Wu, C. S.

    1985-01-01

    The cyclotron maser mechanism which may be responsible for the generation of auroral kilometric radiation and Z-mode radiation is discussed. Emphasis is placed on the basic concepts of the cyclotron maser theory, particularly the relativistic effect of the cyclotron resonance condition. Recent development of the theory is reviewed. Finally, the results of a computer simulation study which helps to understand the nonlinear saturation of the maser instability are reported.

  3. Linear and nonlinear physics of the magnetoacoustic cyclotron instability of fusion-born ions in relation to ion cyclotron emission

    Energy Technology Data Exchange (ETDEWEB)

    Carbajal, L., E-mail: L.Carbajal-Gomez@warwick.ac.uk; Cook, J. W. S. [Centre for Fusion, Space and Astrophysics, Department of Physics, The University of Warwick, Coventry CV4 7AL (United Kingdom); Dendy, R. O. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, Oxfordshire (United Kingdom); Centre for Fusion, Space and Astrophysics, Department of Physics, The University of Warwick, Coventry CV4 7AL (United Kingdom); Chapman, S. C. [Centre for Fusion, Space and Astrophysics, Department of Physics, The University of Warwick, Coventry CV4 7AL (United Kingdom); Department of Mathematics and Statistics, University of Tromsø, N-9037, Tromsø (Norway); Max Planck Institute for the Physics of Complex Systems, D-01187, Dresden (Germany)

    2014-01-15

    The magnetoacoustic cyclotron instability (MCI) probably underlies observations of ion cyclotron emission (ICE) from energetic ion populations in tokamak plasmas, including fusion-born alpha-particles in JET and TFTR [Dendy et al., Nucl. Fusion 35, 1733 (1995)]. ICE is a potential diagnostic for lost alpha-particles in ITER; furthermore, the MCI is representative of a class of collective instabilities, which may result in the partial channelling of the free energy of energetic ions into radiation, and away from collisional heating of the plasma. Deep understanding of the MCI is thus of substantial practical interest for fusion, and the hybrid approximation for the plasma, where ions are treated as particles and electrons as a neutralising massless fluid, offers an attractive way forward. The hybrid simulations presented here access MCI physics that arises on timescales longer than can be addressed by fully kinetic particle-in-cell simulations and by analytical linear theory, which the present simulations largely corroborate. Our results go further than previous studies by entering into the nonlinear stage of the MCI, which shows novel features. These include stronger drive at low cyclotron harmonics, the re-energisation of the alpha-particle population, self-modulation of the phase shift between the electrostatic and electromagnetic components, and coupling between low and high frequency modes of the excited electromagnetic field.

  4. Microwave emission related to cyclotron instabilities in a minimum-B electron cyclotron resonance ion source plasma

    Science.gov (United States)

    Izotov, I.; Tarvainen, O.; Mansfeld, D.; Skalyga, V.; Koivisto, H.; Kalvas, T.; Komppula, J.; Kronholm, R.; Laulainen, J.

    2015-08-01

    Electron cyclotron resonance ion sources (ECRIS) have been essential in the research and applications of nuclear physics over the past 40 years. They are extensively used in a wide range of large-scale accelerator facilities for the production of highly charged heavy ion beams of stable and radioactive elements. ECRISs are susceptible to kinetic instabilities due to resonance heating mechanism leading to anisotropic electron velocity distribution function. Instabilities of cyclotron type are a proven cause of frequently observed periodic bursts of ‘hot’ electrons and bremsstrahlung, accompanied with emission of microwave radiation and followed by considerable drop of multiply charged ions current. Detailed studies of the microwave radiation associated with the instabilities have been performed with a minimum-B 14 GHz ECRIS operating on helium, oxygen and argon plasmas. It is demonstrated that during the development of cyclotron instability ‘hot’ electrons emit microwaves in sub-microsecond scale bursts at temporally descending frequencies in the 8-15 GHz range with two dominant frequencies of 11.09 and 12.59 GHz regardless of ECRIS settings i.e. magnetic field strength, neutral gas pressure or species and microwave power. The experimental data suggest that the most probable excited plasma wave is a slow extraordinary Z-mode propagating quasi-longitudinally with respect to the external magnetic field.

  5. Sport Management Taught On-Line: A Discussion

    Directory of Open Access Journals (Sweden)

    William F. Stier Jr

    2009-01-01

    Full Text Available An introduction to the world of on-line courses (distance education/learning is presented. In addition, the world of on-line learning, as it pertains to sport management, is examined within the framework of (a pedagogy, (b finances,(c assessment, and (d choosing to transition from the traditional classroom to on-line learning. Pertinent points relative to each of the four categories are presented from the literature. In an effort to stimulate thought and discussion to the subject of on-line learning for sport management programs/courses the authors provide their reactions to the literature points by presenting their comments/reactions from a sport management perspective. Sport management professors and administrators are encouraged to critically examine the feasibility of such on-line courses (distance education/learning within their own curricula while maintaining an appropriate framework revolving around sound theoretical instructional strategies, methods as well as appropriate use of instructional tools, including but not limited to, computersand the WWW.

  6. Experimentally obtaining on-line FRA in transformers by injecting controlled pulses

    Directory of Open Access Journals (Sweden)

    Eduardo Gómez-Luna

    2013-04-01

    Full Text Available Transformer monitoring based on the operating condition (on-line test has boomed in recent years because it allows early detection of risk situations or limitations regarding use to make appropriate decisions before a failure occurs. Frequency response analysis (FRA is one of the most heavily researched techniques for on-line development; it is based on obtaining a transformer’s frequency response (admittance, impedance or transfer function in a given bandwidth. This paper presents an experimental method for obtaining the frequency response with the transformer in service by injecting controlled pulses of the voltage signal using an external electronic circuit. Once the voltage and current signals had been recorded, the wavelet transform was used via multi-resolution analysis (MRA for filtering. This led to results being obtained without noise interference from the electrical system. The transfer function was obtained in terms of impedance, using the fast Fourier transform (FFT. The proposed method represented an alternative in solving some problems arising from the on-line FRA technique such as filtering and results’ repeatability. The tests involved a 5-kVA 1150/345 V three-phase transformer and a 3-kVA, 7620/240 V single-phase transformer in the Universidad del Valle’s High Voltage Laboratory.

  7. On-line monitoring of the crystallization process: relationship between crystal size and electrical impedance spectra

    Science.gov (United States)

    Zhao, Yanlin; Yao, Jun; Wang, Mi

    2016-07-01

    On-line monitoring of crystal size in the crystallization process is crucial to many pharmaceutical and fine-chemical industrial applications. In this paper, a novel method is proposed for the on-line monitoring of the cooling crystallization process of L-glutamic acid (LGA) using electrical impedance spectroscopy (EIS). The EIS method can be used to monitor the growth of crystal particles relying on the presence of an electrical double layer on the charged particle surface and the polarization of double layer under the excitation of alternating electrical field. The electrical impedance spectra and crystal size were measured on-line simultaneously by an impedance analyzer and focused beam reflectance measurement (FBRM), respectively. The impedance spectra were analyzed using the equivalent circuit model and the equivalent circuit elements in the model can be obtained by fitting the experimental data. Two equivalent circuit elements, including capacitance (C 2) and resistance (R 2) from the dielectric polarization of the LGA solution and crystal particle/solution interface, are in relation with the crystal size. The mathematical relationship between the crystal size and the equivalent circuit elements can be obtained by a non-linear fitting method. The function can be used to predict the change of crystal size during the crystallization process.

  8. On-line tribochemical strengthening of gear surface

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It has been found that under favorable friction conditions some antiwear elements inlubricating additives can permeate into subsurface of metal which can strengthens the friction sur-faces and improves anti-wear capacity of frication pairs. It is in many ways similar to chemical heattreatment. A new concept, technology of on-line strengthening, was logically put forward. Based oncurrent gear surface treatment technology, the on-line strengthen of gear surface is proposed. Itsdesign method is established. Based on it, the on-line strengthen of gear is achieved on CL-100gear test machine. A new method is put forward for strengthen treatment of gear surface. Andthree kinds of surface film were suggested.

  9. Strengthening weak ties through on-line gaming

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana Virginia; Kirchner, Kathrin

    On-line gaming became widespread in the last couple of years. The aim of the research presented in the paper is to figure out to what extent does game playing helps to strengthen weak ties and what additional factors influence this process. The approach is rather exploratory – some factors...... are grounded in theory, some are new. These factors are age, gender, place of origin, number of their Facebook connections (friends in Facebook terminology), the amount of time they are on Facebook, the amount of time they keep the Facebook site open, the amount of time they play on-line games, and the reasons...... for starting to play on-line games. Regarding the latter, we chose to focus only on escapist reasons....

  10. On-Line Voltage Stability Assessment based on PMU Measurements

    DEFF Research Database (Denmark)

    Garcia-Valle, Rodrigo; P. Da Silva, Luiz C.; Nielsen, Arne Hejde

    2009-01-01

    through statistic analysis. During the off-line analysis, a memory of high-risk situations following a pre-defined voltage stability criterion is obtained. Thereafter, basic statistics analyses are applied resulting in the definition of voltage regions. During on-line operation, voltage magnitudes......This paper presents a method for on-line monitoring of risk voltage collapse based on synchronised phasor measurement. As there is no room for intensive computation and analysis in real-time, the method is based on the combination of off-line computation and on-line monitoring, which are correlated...... of critical buses obtained by phasor measurements are monitored in relation to the risk regions. Comprehensive studies demonstrate that the proposed method could assist operators to avoid voltage collapse events, by taking preventive or emergency actions....

  11. On-line laser spectroscopy with thermal atomic beams

    CERN Document Server

    Thibault, C; De Saint-Simon, M; Duong, H T; Guimbal, P; Huber, G; Jacquinot, P; Juncar, P; Klapisch, Robert; Liberman, S; Pesnelle, A; Pillet, P; Pinard, J; Serre, J M; Touchard, F; Vialle, J L

    1981-01-01

    On-line high resolution laser spectroscopy experiments have been performed in which the light from a CW tunable dye laser interacts at right angles with a thermal atomic beam. /sup 76-98/Rb, /sup 118-145 /Cs and /sup 208-213/Fr have been studied using the ionic beam delivered by the ISOLDE on-line mass separator at CERN while /sup 30-31/Na and /sup 38-47/K have been studied by setting the apparatus directly on-line with the PS 20 GeV proton beam. The principle of the method is briefly explained and some results concerning nuclear structure are given. The hyperfine structure, spins and isotope shifts of the alkali isotopes and isomers are measured. (8 refs).

  12. On-line Payment System Survey – eCash

    Directory of Open Access Journals (Sweden)

    Marius Popa

    2009-12-01

    Full Text Available The paper presents the main aspects regarding an on-line payment system. Some characteristics of such system are presented and an existing system is analyzed. On its fundamental sense, the electronic commerce is a concept that represents the purchase and sale process or exchange of products, services, information, using o computer network, inclusively the Internet. In the most part of the cases, the electronic commerce imply on-line payments that lead to creation of some kinds of electronic money and some specific payment systems. There are described the some electronic payment mechanisms and the architecture and the functions of the on-line payment system E-Cash are depicted.

  13. Electromagnetic waves near the proton cyclotron frequency: Stereo observations

    Energy Technology Data Exchange (ETDEWEB)

    Jian, L. K. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Wei, H. Y.; Russell, C. T. [Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095 (United States); Luhmann, J. G. [Space Science Laboratory, University of California, Berkeley, CA 94720 (United States); Klecker, B. [Max-Planck-Institut für Extraterrestrische Physik, D-85741 Garching (Germany); Omidi, N. [Solana Scientific Inc., Solana Beach, CA 92075 (United States); Isenberg, P. A. [Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824 (United States); Goldstein, M. L.; Figueroa-Viñas, A. [Heliophysics Science Division, NASA Goddard Space Flight Center, MD 20771 (United States); Blanco-Cano, X., E-mail: lan.jian@nasa.gov [Instituto de Geofisica, Universidad Nacional Autónoma de México, Coyoacán D.F. (Mexico)

    2014-05-10

    Transverse, near-circularly polarized, parallel-propagating electromagnetic waves around the proton cyclotron frequency were found sporadically in the solar wind throughout the inner heliosphere. They could play an important role in heating and accelerating the solar wind. These low-frequency waves (LFWs) are intermittent but often occur in prolonged bursts lasting over 10 minutes, named 'LFW storms'. Through a comprehensive survey of them from Solar Terrestrial Relations Observatory A using dynamic spectral wave analysis, we have identified 241 LFW storms in 2008, present 0.9% of the time. They are left-hand (LH) or right-hand (RH) polarized in the spacecraft frame with similar characteristics, probably due to Doppler shift of the same type of waves or waves of intrinsically different polarities. In rare cases, the opposite polarities are observed closely in time or even simultaneously. Having ruled out interplanetary coronal mass ejections, shocks, energetic particles, comets, planets, and interstellar ions as LFW sources, we discuss the remaining generation scenarios: LH ion cyclotron instability driven by greater perpendicular temperature than parallel temperature or by ring-beam distribution, and RH ion fire hose instability driven by inverse temperature anisotropy or by cool ion beams. The investigation of solar wind conditions is compromised by the bias of the one-dimensional Maxwellian fit used for plasma data calibration. However, the LFW storms are preferentially detected in rarefaction regions following fast winds and when the magnetic field is radial. This preference may be related to the ion cyclotron anisotropy instability in fast wind and the minimum in damping along the radial field.

  14. The Cyclotron Production and Nuclear Imaging of BROMINE-77.

    Science.gov (United States)

    Galiano, Eduardo

    In this investigation, bromine-77 was produced with a medical cyclotron and imaged with gamma cameras. Br -77 emits a 240 kev photon with a half life of 56 hours. The C-Br bond is stronger than the C-I bond and bromine is not collected in the thyroid. Bromine can be used to label many organic molecules by methods analogous to radioiodination. The only North American source of Br-77 in the 70's and 80's was Los Alamos National Laboratory, but it discontinued production in 1989. In this method, a p,3n reaction on Br-77 produces Kr-77 which decays with a 1.2 hour half life to Br-77. A cyclotron generated 40 MeV proton beam is incident on a nearly saturated NaBr or LiBr solution contained in a copper or titanium target. A cooling chamber through which helium gas is flowed separates the solution from the cyclotron beam line. Helium gas is also flowed through the solution to extract Kr-77 gas. The mixture flows through a nitrogen trap where Kr-77 freezes and is allowed to decay to Br-77. Eight production runs were performed, three with a copper target and five with a titanium target with yields of 40, 104, 180, 679, 1080, 685, 762 and 118 uCi respectively. Gamma ray spectroscopy has shown the product to be very pure, however corrosion has been a major obstacle, causing the premature retirement of the copper target. Phantom and in-vivo rat nuclear images, and an autoradiograph in a rat are presented. The quality of the nuclear scans is reasonable and the autoradiograph reveals high isotope uptake in the renal parenchyma, a more moderate but uniform uptake in pulmonary and hepatic tissue, and low soft tissue uptake. There is no isotope uptake in the brain or the gastric mucosa.

  15. Hospital based superconducting cyclotron for neutron therapy: Medical physics perspective

    Science.gov (United States)

    Yudelev, M.; Burmeister, J.; Blosser, E.; Maughan, R. L.; Kota, C.

    2001-12-01

    The neutron therapy facility at the Gershenson Radiation Oncology Center, Harper University Hospital in Detroit has been operational since September 1991. The d(48.5)+Be beam is produced in a gantry mounted superconducting cyclotron designed and built at the National Superconducting Cyclotron Laboratory (NSCL). Measurements were performed in order to obtain the physical characteristics of the neutron beam and to collect the data necessary for treatment planning. This included profiles of the dose distribution in a water phantom, relative output factors and the design of various beam modifiers, i.e., wedges and tissue compensators. The beam was calibrated in accordance with international protocol for fast neutron dosimetry. Dosimetry and radiobiology intercomparions with three neutron therapy facilities were performed prior to clinical use. The radiation safety program was established in order to monitor and reduce the exposure levels of the personnel. The activation products were identified and the exposure in the treatment room was mapped. A comprehensive quality assurance (QA) program was developed to sustain safe and reliable operation of the unit at treatment standards comparable to those for conventional photon radiation. The program can be divided into three major parts: maintenance of the cyclotron and related hardware; QA of the neutron beam dosimetry and treatment delivery; safety and radiation protection. In addition the neutron beam is used in various non-clinical applications. Among these are the microdosimetric characterization of the beam, the effects of tissue heterogeneity on dose distribution, the development of boron neutron capture enhanced fast neutron therapy and variety of radiobiology experiments.

  16. Cyclotron resonance studies on InAs/GaSb heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Petchsingh, Cattleya

    2002-07-01

    Far-infrared cyclotron resonance is used to study the magneto-optical properties of semimetallic InAs/GaSb heterostructures. Spatially separated two-dimensional electron and hole gases coexist in this 'broken-gap' type-ll system due to charge transfer across the interfaces. Hybridisations of the overlapping electron and hole wavefunctions are investigated experimentally in samples of varying growth parameters. A self-consistent 8-band k{center_dot}p model is used to assist in the interpretation of experimental results. In samples subjected to varying magnetic field, hybridisations result in oscillations of cyclotron resonance mass, amplitude and linewidth, accompanied by transition splittings in the vicinity of Landau level anticrossings. Asymmetries introduced by InSb interface biasing enhance these effects. Comparison of samples with varying confinement energies (at specified magnetic field) shows effective mass enhancement greater than the standard nonparabolicity effect. The mass enhancement increases with hybridisation strength. A simple two-band minigap model gives good agreement with experimental results. Tilled field measurements show that hybridisation suppresses electron cyclotron resonance transitions. Increased resonance amplitudes at higher temperatures are therefore ascribed to reduced hybridisation strength. Strong evidence of Coulomb interactions between different single particle transitions shows the interactions increasing with temperature, leading to a single motion-averaged transition at sufficiently high temperature. High magnetic field measurements near the quantum limit show transition features generally consistent with electron-hole Landau level hybridisation. Multiple splittings in this field range (14-27T) are ascribed to spin splitting and subband coupling effects. Breaking of selection rules is suggested to be due to inherent band asymmetries in the samples. For narrow well samples, some transition features remain unexplained

  17. The User-friendly On-Line Diffusion Chamber

    CERN Document Server

    Aviles Acosta, Jaime

    2015-01-01

    The On-Line Diffusion Chamber is a stand-alone apparatus built to carry out short-live radiotracer diffusion studies. The availability of the on-demand production of isotopes in the ISOLDE facility, and the design of the apparatus to streamline the implantation process, annealing treatment, ion gun ablation with a tape transport system, and radiation intensity measurement with a Ge gamma detector all in the same apparatus, gives the On-Line Diffusion Chamber a unique ability to studies with short-lived radioisotopes or isomer states that are not possible in any other facility in the world.

  18. On-line measurement of heat of combustion

    Science.gov (United States)

    Chaturvedi, S. K.; Chegini, H.

    1988-01-01

    An experimental method for an on-line measurement of heat of combustion of a gaseous hydrocarbon fuel mixture of unknown composition is developed. It involves combustion of a test gas with a known quantity of air to achieve a predetermined oxygen concentration level in the combustion products. This is accomplished by a feedback controller which maintains the gas volumetric flow rate at a level consistent with the desired oxygen concentration in the products. The heat of combustion is determined from a known correlation with the gas volumetric flow rate. An on-line microcomputer accesses the gas volumetric flow data, and displays the heat of combustion values at desired time intervals.

  19. 5th Computer Science On-line Conference

    CERN Document Server

    Senkerik, Roman; Oplatkova, Zuzana; Silhavy, Petr; Prokopova, Zdenka

    2016-01-01

    This volume is based on the research papers presented in the 5th Computer Science On-line Conference. The volume Artificial Intelligence Perspectives in Intelligent Systems presents modern trends and methods to real-world problems, and in particular, exploratory research that describes novel approaches in the field of artificial intelligence. New algorithms in a variety of fields are also presented. The Computer Science On-line Conference (CSOC 2016) is intended to provide an international forum for discussions on the latest research results in all areas related to Computer Science. The addressed topics are the theoretical aspects and applications of Computer Science, Artificial Intelligences, Cybernetics, Automation Control Theory and Software Engineering.

  20. On-Line Generation of 3D-Waves

    DEFF Research Database (Denmark)

    Frigaard, Peter

    1992-01-01

    The paper describes the technique of filtering white noise for on-line generation of 3D-waves on a small computer in the laboratory. The wave generation package is implemented and tested in the 3D-wave basin at the University of Aalborg.......The paper describes the technique of filtering white noise for on-line generation of 3D-waves on a small computer in the laboratory. The wave generation package is implemented and tested in the 3D-wave basin at the University of Aalborg....

  1. Effects of electron-cyclotron instabilities on gyrotron beam quality

    Energy Technology Data Exchange (ETDEWEB)

    Jost, G.; Tran, T.M.; Appert, K. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP); Wuethrich, S. [CRAY Research, PATP/PSE, EPFL, Lausanne (Switzerland)

    1996-02-01

    A two-dimensional PIC code aimed at the investigation of electron-cyclotron beam instabilities in gyrotrons and their effects on the beam quality is presented. The code is based on recently developed techniques for handling charge conservation and open boundaries. It has been implemented on the massively parallel computer CRAY T3D. First results show an electromagnetic backward instability periodically growing and decaying to energy levels close to those obtained from the electrostatic Bernstein wave instability. On the average, the resulting beam degradation is 3 to 4 times larger than that predicted by electrostatic models. (author) 8 figs., 14 refs.

  2. Cyclotron production of Ac-225 for targeted alpha therapy.

    Science.gov (United States)

    Apostolidis, C; Molinet, R; McGinley, J; Abbas, K; Möllenbeck, J; Morgenstern, A

    2005-03-01

    The feasibility of producing Ac-225 by proton irradiation of Ra-226 in a cyclotron through the reaction Ra-226(p,2n)Ac-225 has been experimentally demonstrated for the first time. Proton energies were varied from 8.8 to 24.8 MeV and cross-sections were determined by radiochemical analysis of reaction yields. Maximum yields were reached at incident proton energies of 16.8 MeV. Radiochemical separation of Ac-225 from the irradiated target yielded a product suitable for targeted alpha therapy of cancer.

  3. RF sources for ITER Ion Cyclotron H and CD system

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian, F., E-mail: fabienne.kazarian@iter.org [ITER Organization, CS 90 046, 13067 Sain-Paul-Les-Durance (France); Beaumont, B.; Arambhadiya, B.; Gassmann, T.; Lamalle, Ph.; Rathi, D. [ITER Organization, CS 90 046, 13067 Sain-Paul-Les-Durance (France); Mukherjee, A.; Ajesh, P.; Machchhar, H.; Patadia, D.; Patel, M.; Rajnish, K.; Singh, R.; Suthar, G.; Trivedi, R. [ITER India, IPR, Bhat, Gandhinagar 382428, Gujarat (India); Kumazawa, R.; Seki, T.; Saito, K.; Kasahara, H.; Mutoh, T. [National Institute for Fusion Science, Toki 509-5292 (Japan)

    2011-10-15

    The Ion Cyclotron Heating and Current Drive (IC H and CD) system for ITER will provide 20 MW to the plasma. The associated Radio Frequency (RF) source system has to be compliant with all operation modes foreseen in that frame. Their specifications are fully described in this paper and constraints on IC RF source components are detailed, in particular concerning the final stage tube of the amplifier. Results of tests performed under a collaborative work at the National Institute for Fusion Science (NIFS) facility are presented. Consequences on the procurement process by ITER India (II) are deduced.

  4. Calibration of electron cyclotron emission radiometer for KSTAR.

    Science.gov (United States)

    Kogi, Y; Jeong, S H; Lee, K D; Akaki, K; Mase, A; Kuwahara, D; Yoshinaga, T; Nagayama, Y; Kwon, M; Kawahata, K

    2010-10-01

    We developed and installed an electron cyclotron emission radiometer for taking measurements of Korea Superconducting Tokamak Advanced Research (KSTAR) plasma. In order to precisely measure the absolute value of electron temperatures, a calibration measurement of the whole radiometer system was performed, which confirmed that the radiometer has an acceptably linear output signal for changes in input temperature. It was also found that the output power level predicted by a theoretical calculation agrees with that obtained by the calibration measurement. We also showed that the system displays acceptable noise-temperature performance around 0.23 eV.

  5. Solar Wind Electric Fields in the Ion Cyclotron Frequency Range

    CERN Document Server

    Kellogg, P J; Mozer, F S; Horbury, T S; Reme, H

    2006-01-01

    Measurements of fluctuations of electric fields in the frequency range from a fraction of one Hz to 12.5 Hz are presented, and corrected for the Lorentz transformation of magnetic fluctuations to give the electric fields in the plasma frame. The electric fields are large enough to provide the dominant force on the ions of the solar wind in the region near the ion cyclotron frequency of protons, larger than the force due to magnetic fluctuations. They provide sufficient velocity space diffusion or heating to counteract conservation of magnetic moment in the expanding solar wind to maintain nearly isotropic velocity distributions.

  6. Calibration of electron cyclotron emission radiometer for KSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Kogi, Y. [Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Jeong, S. H. [Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Lee, K. D.; Kwon, M. [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Akaki, K.; Mase, A. [KASTEC, Kyushu University, Kasuga 816-8580 (Japan); Kuwahara, D. [Tokyo Institute of Technology, Tokyo 152-8550 (Japan); Yoshinaga, T.; Nagayama, Y.; Kawahata, K. [National Institute for Fusion Science, Toki 509-5292 (Japan)

    2010-10-15

    We developed and installed an electron cyclotron emission radiometer for taking measurements of Korea Superconducting Tokamak Advanced Research (KSTAR) plasma. In order to precisely measure the absolute value of electron temperatures, a calibration measurement of the whole radiometer system was performed, which confirmed that the radiometer has an acceptably linear output signal for changes in input temperature. It was also found that the output power level predicted by a theoretical calculation agrees with that obtained by the calibration measurement. We also showed that the system displays acceptable noise-temperature performance around 0.23 eV.

  7. Automated cyclotron magnetic field measurement at the University of Manitoba

    Science.gov (United States)

    Derenchuk, V.; Bruckshaw, J.; Gusdal, I.; Lancaster, J.; McIlwain, A.; Oh, S.; Pogson, R.; McKee, J. S. C.

    The magnetic field of the University of Manitoba compact cyclotron has been measured in high vacuum by polar scanning with 52 flip coils. This was a unique invacuo operation was required because the Curie effect on invar material is used to trim the field. The data acquisition controller was a Digital Equipment Corporation LSI-11 with CAMAC and IEEE-488 interfaces. Filtering, display and conventional equilibrium orbit analysis were performed off-line by means of a VAX-11/750 computer. A description of the apparatus and software is given.

  8. Field Simulation of Main Magnet for 230 MeV Superconducting Cyclotron

    Institute of Scientific and Technical Information of China (English)

    WANG; Chuan; LI; Ming; ZHANG; Dong-sheng; YIN; Meng; YANG; Jian-jun; CUI; Tao; LV; Yin-long; AN; Shi-zhong; ZHANG; Tian-jue

    2015-01-01

    Superconducting proton cyclotrons have many advantages over competitive accelerators in medium energy range,namely,lower construction cost,lower operation cost,more compact thus more suitable to be installed in limited cite like hospitals.More specifically,as superconducting proton cyclotrons provide CW proton

  9. Electromagnetism applications in nuclear engineering: cyclotron; Aplicacoes do eletromagnetismo na engenharia nuclear; ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Nobrega Bastos; Dalla Riva, Maria Teresa Cristina da

    1995-08-01

    Particle accelerators, with special emphasis on cyclotrons, are presented. Other electromagnetic devices and their importance in technology and research are also shown. An experimental arrangement for positrons source productions using a cyclotron aiming at non-destructive testing for radiations damage studies is presented. 46 refs., 23 figs., 2 tabs.

  10. Monte-Carlo Simulation of Cryopanel Parameter in CYCIAE-100 Cyclotron

    Institute of Scientific and Technical Information of China (English)

    PAN; Gao-feng; ZHANG; Su-ping; XING; Jian-sheng; LI; Zhen-guo; QIN; Jiu-chang

    2015-01-01

    The diameter of CYCIAE-100cyclotron main magnet is 4m,the angle of magnet valley is 35°and its height is about 500mm.Due to restrictions on the size of compact cyclotron structure,the available vacuum suction space is limited.According to the beam loss theory,particles

  11. Theoretical Formula and Simulation of Cyclotron Magnet Shimming in High Field Environment

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Dong-sheng; YANG; Jian-jun; LI; Ming

    2015-01-01

    In the computation of cyclotron magnet shimming,trim-rod and magnetic channel,one common process is to calculate the variation of magnet field caused by a small iron piece.Under the circumstance of superconducting cyclotron,high field approximate can be used and we can derive

  12. Analysis of radionuclide concentration in air released through the stack of a radiopharmaceutical production facility based on a medical cyclotron

    Science.gov (United States)

    Giardina, M.; Tomarchio, E.; Greco, D.

    2015-11-01

    Positron emitting radionuclides are increasingly used in medical diagnostics and the number of radiopharmaceutical production facilities have been estimated to be growing worldwide. During the process of production and/or patient administration of radiopharmaceuticals, an amount of these radionuclides might become airborne and escape into the environment. Therefore, the analysis of radionuclide concentration in the air released to the stack is a very important issue to evaluate the dose to the population living around the plant. To this end, sampling and measurement of radionuclide concentration in air released through the stack of a Nuclear Medicine Center (NMC), provided with a cyclotron for radiopharmaceuticals production, must be routinely carried out with an automatic measurement system. In this work is presented the air monitoring system realized at "San Gaetano" NMC at Bagheria (Italy) besides the analysis of the recorded stack relesead air concentration data. Sampling of air was carried out continuously and gamma-ray spectrometric measurement are made on-line and for a short time by using a shielded Marinelli beaker filled with sampled air and a gamma detector. The use of this system allows to have 1440 values of air concentration per day from 2002, year of the start of operation with the cyclotron. Therefore, the concentration values are very many and an analysis software is needed to determine the dose to the population. A comparison with the results of a simulation code based on a Gaussian Plume air dispersion modelling allow us to confirm the no-radiological significance of the stack effluent releases in terms of dose to population and to evaluate possible improvements in the plant devices to reduce the air concentration at stack.

  13. A new generation of medical cyclotrons for the 90's

    Energy Technology Data Exchange (ETDEWEB)

    Milton, B.F

    1995-08-01

    Cyclotrons continue to be efficient accelerators for use in radio-isotope production. In recent years, developments in accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicates a strong future for commercial cyclotrons. In this paper we will survey recent developments in the areas of cyclotron technology as they relate to the new generation of commercial cyclotrons. Existing and potential markets for these cyclotrons will be presented. We will also discuss the possibility of systems capable of extracted energies up to 150 MeV and extracted beam currents of up to 2.0 mA. (author)

  14. The dynamics of on-line principal component analysis

    NARCIS (Netherlands)

    Biehl, M.; Schlösser, E.

    1998-01-01

    The learning dynamics of an on-line algorithm for principal component analysis is described exactly in the thermodynamic limit by means of coupled ordinary differential equations for a set of order parameters. It is demonstrated that learning is delayed significantly because existing symmetries amon

  15. On-line sample treatment - Capillary gas chromatography

    NARCIS (Netherlands)

    Goosens, EC; de Jong, D; de Jong, GJ; Brinkman, UAT

    1998-01-01

    Sample pretreatment is often the bottleneck of a trace level analytical procedure. In order to increase performance, increasing attention is therefore being devoted to combining sample pretreatment on-line with the separation technique that has to be used. In the present review, a variety of procedu

  16. Specialization processes in on-line unsupervised learning

    NARCIS (Netherlands)

    Biehl, M.; Freking, A.; Reents, G.; Schlösser, E.

    1998-01-01

    From the recent analysis of supervised learning by on-line gradient descent in multilayered neural networks it is known that the necessary process of student specialization can be delayed significantly. We demonstrate that this phenomenon also occurs in various models of unsupervised learning. A sol

  17. On-Line Learning and the Implications for School Design

    Science.gov (United States)

    Stack, Greg

    2011-01-01

    "Disrupting Class," published in 2008, is the story of how disruptive innovation, innovation that changes the business model organizations, will fundamentally change the American school system. The book's most startling prediction is that half of all high school classes will be on-line by 2019. In considering these predictions, the author began to…

  18. On-line EM algorithm for the normalized gaussian network.

    Science.gov (United States)

    Sato, M; Ishii, S

    2000-02-01

    A normalized gaussian network (NGnet) (Moody & Darken, 1989) is a network of local linear regression units. The model softly partitions the input space by normalized gaussian functions, and each local unit linearly approximates the output within the partition. In this article, we propose a new on-line EMalgorithm for the NGnet, which is derived from the batch EMalgorithm (Xu, Jordan, &Hinton 1995), by introducing a discount factor. We show that the on-line EM algorithm is equivalent to the batch EM algorithm if a specific scheduling of the discount factor is employed. In addition, we show that the on-line EM algorithm can be considered as a stochastic approximation method to find the maximum likelihood estimator. A new regularization method is proposed in order to deal with a singular input distribution. In order to manage dynamic environments, where the input-output distribution of data changes over time, unit manipulation mechanisms such as unit production, unit deletion, and unit division are also introduced based on probabilistic interpretation. Experimental results show that our approach is suitable for function approximation problems in dynamic environments. We also apply our on-line EM algorithm to robot dynamics problems and compare our algorithm with the mixtures-of-experts family.

  19. A New On-Line Resource for Psycholinguistic Studies

    Science.gov (United States)

    Szekely, Anna; Jacobsen, Thomas; D'Amico, Simona; Devescovi, Antonella; Andonoa, Elena; Herron, Daniel; Lu, Ching Ching; Pechmann, Thomas; Pleh, Csaba; Wicha, Nicole; Federmeier, Kara; Gerdjikova, Irina; Gutierrez, Gabriel; Hung, Daisy, Hsu, Jeanne; Iyer, Gowri; Kohnert, Kathryn; Mehotcheva, Teodora; Orozco-Figueroa, Araceli; Tzeng, Angela; Tzeng, Ovid; Arevalo, Analia; Vargha, Andras; Butler, Andrew C.; Buffington, Robert; Bates, Elizabeth

    2004-01-01

    Picture naming is a widely used technique in psycholinguistic studies. Here, we describe new on-line resources that our project has compiled and made available to researchers on the world wide web at http://crl.ucsd.edu/~aszekely/ipnp/. The website provides access to a wide range of picture stimuli and related norms in seven languages. Picture…

  20. Why do People Stop playing On-Line Games?

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana

    2012-01-01

    The recent initial public offering of shares of Zynga, probably the most important on-line game provider, drew interest of potential investors but also of general public to their business model. What the most interested people learned so far is that if Zynga had not changed their accounting...

  1. Developing an On-Line Interactive Health Psychology Module

    Science.gov (United States)

    Upton, Dominic; Cooper, Carol

    2006-01-01

    On-line teaching material in health psychology was developed which ensured a range of students could access appropriate material for their course and level of study. This material has been developed around the concept of smaller "content chunks" which can be combined into whole units of learning (topics), and ultimately, a module. On the basis of…

  2. Efficiently Building On-line Tools for Distributed Heterogeneous Environments

    Directory of Open Access Journals (Sweden)

    Günther Rackl

    2002-01-01

    Full Text Available Software development is getting more and more complex, especially within distributed middleware-based environments. A major drawback during the overall software development process is the lack of on-line tools, i.e. tools applied as soon as there is a running prototype of an application. The MIMO MIddleware MOnitor provides a solution to this problem by implementing a framework for an efficient development of on-line tools. This paper presents a methodology for developing on-line tools with MIMO. As an example scenario, we choose a distributed medical image reconstruction application, which represents a test case with high performance requirements. Our distributed, CORBA-based application is instrumented for being observed with MIMO and related tools. Additionally, load balancing mechanisms are integrated for further performance improvements. As a result, we obtain an integrated tool environment for observing and steering the image reconstruction application. By using our rapid tool development process, the integration of on-line tools shows to be very convenient and enables an efficient tool deployment.

  3. Investigating on-line pornography at the University of Johannesburg

    Directory of Open Access Journals (Sweden)

    P. Laughton

    2008-01-01

    Full Text Available The on-line user of today has access to a vast collection of information resources. In addition, the developments in Internet and Web technologies have made it even easier for surfers to anonymously get access to on-line pornography. The purpose of this research was to investigate the extent to which access to on-line pornography at the University of Johannesburg can be managed. For the empirical part of this research 1037 questionnaires were proportionally distributed to and completed by students on all five campuses of the university. The questionnaire consisted of four sections: biographical information; university computer facility usage; university acceptable use policy; and personal experience with university computer facilities. The gender distribution for the sample was almost even, with a total of 49,4% male participants and 50,6% female, with the largest grouping of respondents (61,6% aged between 19 years and 21 years. Of the respondents, 36,7% indicated that exposure to unsolicited pornography did not bother them. When asked to what extent students should have access to pornography, 60,5% stated 'None' while 32,6% believed that 'Restricted' access should be granted for research purposes and 6,9% believed that students should be granted 'Total' access to pornography. Results from the research will be used to manage access to on-line resources at the University of Johannesburg better.

  4. Investigating on-line pornography at the University of Johannesburg

    Directory of Open Access Journals (Sweden)

    P. Laughton

    2007-12-01

    Full Text Available The on-line user of today has access to a vast collection of information resources. In addition, the developments in Internet and Web technologies have made it even easier for surfers to anonymously get access to on-line pornography. The purpose of this research was to investigate the extent to which access to on-line pornography at the University of Johannesburg can be managed. For the empirical part of this research 1037 questionnaires were proportionally distributed to and completed by students on all five campuses of the university. The questionnaire consisted of four sections: biographical information; university computer facility usage; university acceptable use policy; and personal experience with university computer facilities. The gender distribution for the sample was almost even, with total of 49,4% male participants and 50,6% female, with the largest grouping of respondents(61,6% aged between 19 years and 21 years. Of the respondents, 36,7% indicated that exposure to unsolicited pornography did not bother them. When asked to what extent students should have access to pornography, 60,5% stated 'None' while 32,6% believed that 'Restricted' access should be granted for research purposes and 6,9% believed that students should be granted 'Total' access to pornography. Results from the research will be used to manage access to on-line resources at the University of Johannesburg better.

  5. On-line multidimensional separation systems for peptide analysis

    NARCIS (Netherlands)

    Stroink, T.

    2005-01-01

    Today, there is an increasing interest in selective and sensitive analysis of proteins and peptides with a relatively high speed. The first chapter of this thesis describes several strategies for the on-line multidimensional analysis of peptides and proteins in biological samples. This overview of t

  6. On-line probabilistic classification with particle filters

    DEFF Research Database (Denmark)

    Højen-Sørensen, Pedro; de Freitas, N.; Fog, Torben L.

    2000-01-01

    We apply particle filters to the problem of on-line classification with possibly overlapping classes. This allows us to compute the probabilities of class membership as the classes evolve. Although we adopt neural network classifiers, the work can be extended to any other parametric classification...

  7. On-Line Synthesis and Analysis by Mass Spectrometry

    Science.gov (United States)

    Bain, Ryan M.; Pulliam, Christopher J.; Raab, Shannon A.; Cooks, R. Graham

    2015-01-01

    In this laboratory experiment, students learn how to use ESI to accelerate chemical synthesis and to couple it with on-line mass spectrometry for structural analysis. The Hantzsch synthesis of symmetric 1,4-dihydropyridines is a classic example of a one-pot reaction in which multiple intermediates can serve to indicate the progress of the reaction…

  8. Why do People Stop Playing On-Line Games?

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana

    2012-01-01

    The recent initial public offering of shares of Zynga, probably the most important on-line game provider, drew interest of potential investors but also of general public to their business model. What the most interested people learned so far is that if Zynga had not changed their accounting...

  9. On-Line NDE for Advanced Reactor Designs

    Science.gov (United States)

    Nakagawa, N.; Inanc, F.; Thompson, R. B.; Junker, W. R.; Ruddy, F. H.; Beatty, J. M.; Arlia, N. G.

    2003-03-01

    This expository paper introduces the concept of on-line sensor methodologies for monitoring the integrity of components in next generation power systems, and explains general benefits of the approach, while describing early conceptual developments of suitable NDE methodologies. The paper first explains the philosophy behind this approach (i.e. the design-for-inspectability concept). Specifically, we describe where and how decades of accumulated knowledge and experience in nuclear power system maintenance are utilized in Generation IV power system designs, as the designs are being actively developed, in order to advance their safety and economy. Second, we explain that Generation IV reactor design features call for the replacement of the current outage-based maintenance by on-line inspection and monitoring. Third, the model-based approach toward design and performance optimization of on-line sensor systems, using electromagnetic, ultrasonic, and radiation detectors, will be explained. Fourth, general types of NDE inspections that are considered amenable to on-line health monitoring will be listed. Fifth, we will describe specific modeling developments to be used for radiography, EMAT UT, and EC detector design studies.

  10. Design of the ion cyclotron system for TPX

    Energy Technology Data Exchange (ETDEWEB)

    Swain, D.; Shipley, S.; Yugo, J.; Goulding, R.; Batchelor, D.; Stallings, D. [Oak Ridge National Lab., TN (United States); Fredd, E. [Princeton Univ., NJ (United States). Plasma Physics Lab.

    1993-06-01

    The TPX experiment will operate for very long pulse times ({ge} 1000 s) and will require current drive of several different types to explore the advanced physics operating modes as one of its main missions. Fast wave current drive (FWCD) using ion cyclotron waves in the 40--80 MHz range will be used as one of the main current-drive mechanisms. For initial operation, 8 MW of rf will be supplied, along with 8 MW of neutral beams and 1.5 MW of lower hybrid power. The ion cyclotron (IC) system is a major part of the TPX heating and current drive system. The IC system must: supply 8 MW of power through two main horizontal ports; be upgradable to provide up to 12 MW of rf power through two ports; operate, for 1000-s pulses every 75 min; drive current using FWCD with high reliability; be bakeable to 350{degree}C for cleaning; and incorporate shielding to attenuate the neutron and gamma flux from DD operation so that hands-on maintenance can be performed exterior to the vacuum vessel. The system will consist of four modified FMIT power units that will be upgraded to deliver 2 MW each to the plasma. Two antennas, each with six current straps, will be located in adjacent ports. A sophisticated matching system is needed to provide experimental flexibility and reliability.

  11. Design of the ion cyclotron system for TPX

    Energy Technology Data Exchange (ETDEWEB)

    Swain, D.; Shipley, S.; Yugo, J.; Goulding, R.; Batchelor, D.; Stallings, D. (Oak Ridge National Lab., TN (United States)); Fredd, E. (Princeton Univ., NJ (United States). Plasma Physics Lab.)

    1993-01-01

    The TPX experiment will operate for very long pulse times ([ge] 1000 s) and will require current drive of several different types to explore the advanced physics operating modes as one of its main missions. Fast wave current drive (FWCD) using ion cyclotron waves in the 40--80 MHz range will be used as one of the main current-drive mechanisms. For initial operation, 8 MW of rf will be supplied, along with 8 MW of neutral beams and 1.5 MW of lower hybrid power. The ion cyclotron (IC) system is a major part of the TPX heating and current drive system. The IC system must: supply 8 MW of power through two main horizontal ports; be upgradable to provide up to 12 MW of rf power through two ports; operate, for 1000-s pulses every 75 min; drive current using FWCD with high reliability; be bakeable to 350[degree]C for cleaning; and incorporate shielding to attenuate the neutron and gamma flux from DD operation so that hands-on maintenance can be performed exterior to the vacuum vessel. The system will consist of four modified FMIT power units that will be upgraded to deliver 2 MW each to the plasma. Two antennas, each with six current straps, will be located in adjacent ports. A sophisticated matching system is needed to provide experimental flexibility and reliability.

  12. Response of thermal ions to electromagnetic ion cyclotron waves

    Science.gov (United States)

    Anderson, B. J.; Fuselier, S. A.

    1994-01-01

    Electromagnetic ion cyclotron waves generated by 10 - 50 keV protons in the Earth's equatorial magnetosphere will interact with the ambient low-energy ions also found in this region. We examine H(+) and He(+) distribution functions from approx. equals 1 to 160 eV using the Hot Plasma Composition Experiment instrument on AMPTE/CCE to investigate the thermal ion response to the waves. A total of 48 intervals were chosen on the basis of electromagnetic ion cyclotron (EMIC) wave activity: 24 with prevalent EMIC waves and 24 with no EMIC waves observed on the orbit. There is a close correlation between EMIC waves and perpendicular heated ion distributions. For protons the perpendicular temperature increase is modest, about 5 eV, and is always observed at 90 deg pitch angles. This is consistent with a nonresonant interaction near the equator. By contrast, He(+) temperatures during EMIC wave events averaged 35 eV and sometimes exceeded 100 eV, indicating stronger interaction with the waves. Furthermore, heated He(+) ions have X-type distributions with maximum fluxes occurring at pitch angles intermediate between field-aligned and perpendicular directions. The X-type He(+) distributions are consistent with a gyroresonant interaction off the equator. The concentration of He(+) relative to H(+) is found to correlate with EMIC wave activity, but it is suggested that the preferential heating of He(+) accounts for the apparent increase in relative He(+) concentration by increasing the proportion of He(+) detected by the ion instrument.

  13. Response of thermal ions to electromagnetic ion cyclotron waves

    Science.gov (United States)

    Anderson, B. J.; Fuselier, S. A.

    1994-10-01

    Electromagnetic ion cyclotron waves generated by 10 - 50 keV protons in the Earth's equatorial magnetosphere will interact with the ambient low-energy ions also found in this region. We examine H(+) and He(+) distribution functions from approx. equals 1 to 160 eV using the Hot Plasma Composition Experiment instrument on AMPTE/CCE to investigate the thermal ion response to the waves. A total of 48 intervals were chosen on the basis of electromagnetic ion cyclotron (EMIC) wave activity: 24 with prevalent EMIC waves and 24 with no EMIC waves observed on the orbit. There is a close correlation between EMIC waves and perpendicular heated ion distributions. For protons the perpendicular temperature increase is modest, about 5 eV, and is always observed at 90 deg pitch angles. This is consistent with a nonresonant interaction near the equator. By contrast, He(+) temperatures during EMIC wave events averaged 35 eV and sometimes exceeded 100 eV, indicating stronger interaction with the waves. Furthermore, heated He(+) ions have X-type distributions with maximum fluxes occurring at pitch angles intermediate between field-aligned and perpendicular directions. The X-type He(+) distributions are consistent with a gyroresonant interaction off the equator. The concentration of He(+) relative to H(+) is found to correlate with EMIC wave activity, but it is suggested that the preferential heating of He(+) accounts for the apparent increase in relative He(+) concentration by increasing the proportion of He(+) detected by the ion instrument.

  14. Polarization in cyclotron radiation in strong magnetic fields

    Institute of Scientific and Technical Information of China (English)

    Luidmila Semionova; Denis Leahy; Jorge Paez

    2010-01-01

    We revisit the problem of radiative transitions of electrons in the presence of a strong magnetic field.We derive fully relativistic cyclotron transition rates for an arbitrary magnetic field,for any orientation of electron spin and for any polarization of the emitted radiation.Also,we obtain the transition rates for any value of the initial electron's parallel momentum.For very strong magnetic fields,transitions to the ground state predominate.Transition rates summed over the electron's spin orientation and for unpolarized radiation are also obtained,which confirm previous results by Latal.Transition widths are calculated for different electron spin orientations and different polarizations of radiation.We obtain general expressions for transition rates that reduce to the results for the non-relativistic case and for unpolarized radiation.Additionally we get,for the non-relativistic approximation,the transition rates for any polarization of radiation.As an application,the first five emission lines are evaluated and compared to the X-ray emitting neutron star V0332+53,which has multiple observable cyclotron lines,taking into account gravitational redshift.The most probable polarization is ∈(2).

  15. Robust Matching System for the ITER Ion Cyclotron System

    Science.gov (United States)

    Swain, D.; Goulding, R.; Rasmussen, D.; Vervier, M.; Messiaen, A.; Dumortier, P.

    2008-11-01

    The ITER ion cyclotron system is required to deliver 20 MW to the ITER plasma under a number of different operating scenarios. The EU will fabricate the antenna, the US will supply the matching system and transmission lines, and India will deliver the rf sources and high-voltage power supplies. A brief description of the complete ion cyclotron system will be presented, and different design options for the matching system will be discussed. Emphasis will be on analyzing the ability of the system to operate effectively during sudden changes caused by plasma perturbations (e. g., ELMs), and on the robustness of matching algorithms. Particular challenges are: the possibility of relatively low loading of the antenna by the plasma because of a large plasma-antenna distance; the resulting high voltages in the matching system (which must be minimized by good system design); the need to install a number of large matching components in the tight space available near the tokamak; and the requirement for operation and maintenance in a radiation environment.

  16. Superconducting Ring Cyclotron for Riken RI Beam Factory in Japan

    Science.gov (United States)

    Okuno, H.; Dantsuka, T.; Yamada, K.; Kase, M.; Maie, T.; Kamigaito, O.

    2010-04-01

    Since 1997, RIKEN Nishina Center has been constructing the Radioactive Isotope Beam Factory (RIBF) and succeeded in beam commissioning of its accelerator complex at the end of 2006. The world's first superconducting ring cyclotron (SRC) is the final booster in the RIBF accelerator complex which is able to accelerate all-element heavy ions to a speed of about 70% of the velocity of light. The ring cyclotron consists of 6 major superconducting sector magnets with a maximum field of 3.8 T. The total stored energy is 235 MJ, and its overall sizes are 19 m diameter, 8 m height and 8,300 tons. The magnet system assembly was completed in August 2005, and successfully reached the maximum field in November 2005. The first beam was extracted at the end of 2006 and the first uranium beam was extracted in March 2007. However operation of the helium refrigerator was not satisfactory although the commissioning of SRC was successful. Operation was stopped every two month due to degradation of its cooling power. In February 2008 the reason of the degradation was revealed to be oil contamination. Operation of the cryogenic system was restarted from August 2008 after hard task to clean up the helium refrigerator and to add oil separators to the compressor. After restoration long-term steady operation to keep the magnet superconducting continued for about 8 months with no sign of degradation of cooling capacity.

  17. Improvement of dose distribution in phantom by using epithermal neutron source based on the Be(p,n) reaction using a 30 MeV proton cyclotron accelerator.

    Science.gov (United States)

    Tanaka, H; Sakurai, Y; Suzuki, M; Takata, T; Masunaga, S; Kinashi, Y; Kashino, G; Liu, Y; Mitsumoto, T; Yajima, S; Tsutsui, H; Takada, M; Maruhashi, A; Ono, K

    2009-07-01

    In order to generate epithermal neutrons for boron neutron capture therapy (BNCT), we proposed the method of filtering and moderating fast neutrons, which are emitted from the reaction between a beryllium target and 30 MeV protons accelerated by a cyclotron, using an optimum moderator system composed of iron, lead, aluminum, calcium fluoride, and enriched (6)LiF ceramic filter. At present, the epithermal-neutron source is under construction since June 2008 at Kyoto University Research Reactor Institute. This system consists of a cyclotron to supply a proton beam of about 1 mA at 30 MeV, a beam transport system, a beam scanner system for heat reduction on the beryllium target, a target cooling system, a beam shaping assembly, and an irradiation bed for patients. In this article, an overview of the cyclotron-based neutron source (CBNS) and the properties of the treatment neutron beam optimized by using the MCNPX Monte Carlo code are presented. The distribution of the RBE (relative biological effectiveness) dose in a phantom shows that, assuming a (10)B concentration of 13 ppm for normal tissue, this beam could be employed to treat a patient with an irradiation time less than 30 min and a dose less than 12.5 Gy-eq to normal tissue. The CBNS might be an alternative to the reactor-based neutron sources for BNCT treatments.

  18. Mentoring Narratives ON-LINE:Teaching the Principalship

    Directory of Open Access Journals (Sweden)

    Allison I. Griffith

    2002-05-01

    Full Text Available The need to develop new models for preparation of school administrators has been a prominent concern in educational discourse in the last decade. Having been criticized for the inadequate preparation of the school leadership cadre, academic departments responsible for training future school administrators have had to revisit their approaches and to reframe their teaching philosophies to ensure the readiness of their graduates for the challenges and complexities of school leadership. This article reports on the new model of principals' training that has been used in York University's Principals' Qualification Program (PQP from the late 1990s onward. One component of the program brings traditional case methodology into a computer-mediated/on-line environment. The on-line cases are narratives from the everyday lives of the Ontario school administrators who serve as mentors in the on-line environment. Situating our discussion within the context of the rapidly changing educational landscape of Ontario, we focus on the PQP model to explore experientially generated case narratives as one method for teaching and learning the work of the local school administrator. We focus particularly on the teaching and learning embedded in computer-mediated or on-line case narratives used in training teachers for school leadership. We argue that the complexities of school leadership—the social, cultural, relational, ethical and moral context of school leadership—can be taught effectively through the reflective processes of on-line case narratives. We seek to contribute to the ongoing dialogue on the potential of new pedagogies and new technologies to help prepare the competent and responsible leaders for tomorrow's schools.

  19. Astronomy On-Line Programme Enters "hot Week"

    Science.gov (United States)

    1996-11-01

    World's Biggest Astronomy WWW-Event Attracts Thousands of Students The Astronomy On-line Programme (See ESO Press Release 09/96 of 18 June 1996) began officially on 1 October and is now about to enter its most intense phase, known as the Hot Week . On 18 - 22 November, an estimated 4000 astronomy-interested, mostly young people in Europe and on four other continents will get together during five days in what - not unexpected - has become the world's biggest astronomy event ever organised on the World Wide Web. This carefully structured Programme is carried out in collaboration between the European Association for Astronomy Education (EAAE), the European Southern Observatory and the European Commission, under the auspices of the Fourth European Week for Scientific and Technological Culture. The Programme has already had a most visible impact on the school education of natural sciences in various countries; for instance, the Internet-connection of schools has been advanced in some, in order to allow groups to participate. There have been numerous contacts among the groups across the borders and there are clear signs that many Astronomy On-line participants have progressed to use the impressive possibilities of the Web in an efficient and structured way. There has been a lively media interest in Astronomy On-line all over Europe and it is expected to increase during the next week. The current status of Astronomy On-line It is obvious that the pilot function of the Astronomy On-line Programme in the use of the Web has been very effective and that the associated dissemination of astronomical knowledge has been successful. At this time, more than 650 groups have registered with Astronomy On-line. Most come from 31 different European countries and a few dozen groups are located in North and South America as well as in Asia and Australia. Together they have experienced the steady build-up of Astronomy On-line over the past weeks, by means of numerous contributions from a

  20. Power requirements for electron cyclotron current drive and ion cyclotron resonance heating for sawtooth control in ITER

    CERN Document Server

    Chapman, I T; Sauter, O; Zucca, C; Asunta, O; Buttery, R J; Coda, S; Goodman, T; Igochine, V; Johnson, T; Jucker, M; La Haye, R J; Lennholm, M; Contributors, JET-EFDA

    2013-01-01

    13MW of electron cyclotron current drive (ECCD) power deposited inside the q = 1 surface is likely to reduce the sawtooth period in ITER baseline scenario below the level empirically predicted to trigger neo-classical tearing modes (NTMs). However, since the ECCD control scheme is solely predicated upon changing the local magnetic shear, it is prudent to plan to use a complementary scheme which directly decreases the potential energy of the kink mode in order to reduce the sawtooth period. In the event that the natural sawtooth period is longer than expected, due to enhanced alpha particle stabilisation for instance, this ancillary sawtooth control can be provided from > 10MW of ion cyclotron resonance heating (ICRH) power with a resonance just inside the q = 1 surface. Both ECCD and ICRH control schemes would benefit greatly from active feedback of the deposition with respect to the rational surface. If the q = 1 surface can be maintained closer to the magnetic axis, the efficacy of ECCD and ICRH schemes sig...

  1. Alternative metrics

    Science.gov (United States)

    2012-11-01

    As the old 'publish or perish' adage is brought into question, additional research-impact indices, known as altmetrics, are offering new evaluation alternatives. But such metrics may need to adjust to the evolution of science publishing.

  2. Enhanced ion acoustic lines due to strong ion cyclotron wave fields

    Directory of Open Access Journals (Sweden)

    H. Bahcivan

    2008-07-01

    Full Text Available The Fast Auroral Snapshot Explorer (FAST satellite detected intense and coherent 5–20 m electric field structures in the high-latitude topside auroral ionosphere between the altitudes of 350 km and 650 km. These electric fields appear to belong to electrostatic ion cyclotron (EIC waves in terms of their frequency and wavelengths. Numerical simulations of the response of an electron plasma to the parallel components of these fields show that the waves are likely to excite a wave-driven parallel ion acoustic (IA instability, through the creation of a highly non-Maxwellian electron distribution function, which when combined with the (assumed Maxwellian ion distribution function provides inverse Landau damping. Because the counter-streaming threshold for excitation of EIC waves is well below that for excitation of IA waves (assuming Maxwellian statistics our results suggest a possible two step mechanism for destabilization of IA waves. Combining this simulation result with the observational fact that these EIC waves share a common phenomenology with the naturally enhanced IA lines (NEIALS observed by incoherent scatter radars, especially that they both occur near field-aligned currents, leads to the proposition that this two-step mechanism is an alternative path to NEIALS.

  3. Fractal groups: Emergent dynamics in on-line learning communities

    Directory of Open Access Journals (Sweden)

    Junia de Carvalho Fidelis Braga

    Full Text Available Drawing on complexity theory, this work discusses the complex dynamics and emergent patterns of on-line learning communities based on a doctoral study in the area of Applied Linguistics. The analysis will center on the interlocutions of fifty students who interacted in small groups without the teacher's direct intervention, in an undergraduate course offered by the School of Languages and Literature at the Federal University of Minas Gerais. By analyzing the data, I demonstrate that out of the interactions among the peers of autonomous on-line learning communities arise opportunities for the construction of shared meaning, distributed leadership, as well as other dynamics. I also demonstrate the fractal nature of these communities. Moreover, I discuss how these findings shed light on the creation and development of course designs for large groups.

  4. Escapist Motives for Playing On-Line Games

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana

    , Harteveld and Mayer’s framework (2009) of escapist motives, which identifies four main motives for playing on-line games: mundane breaking, stress relieving, pleasure seeking, and imagination conjuring. In the paper, we report preliminary findings from an exploratory questionnaire survey. Besides importance...... of escapist motives for playing Facebook and other on-line games, we investigate how they are linked to demographic data such as: age, gender, place of origin, along with other social interactions patterns and social network usage behavior, current gaming status and an estimate of gaming time. According......Social games have become popular along with the tremendous growth of social networking sites, esp. Facebook. There is a gap in literature on what motivates people to play Facebook games. This paper studies social games usage behavior of students. We focus on escapist reasons, based on Warmelink...

  5. On-line Measuring Method for Shell Chamber Volume

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li-zhong; WANG De-min; JIANG Tao; CAO Guo-hua; WANG Qi

    2005-01-01

    Using the ideal gas state equation, an on-line measuring method for the shell chamber volume is studied in this paper. After analyzing how various measurement parameters affect the measurement accuracy, the system parameters are optimized in this method. Because the shape and volume of the tested items are similar, the method of using "tamping" to raise the accuracy and speed of the measurement is put forward. Based on the work above, a prototype of the testing instrument for shell chamber volume was developed, automatically testing and controlling. Compared with the method of "water weight", this method is more accurate, quicker and more automotive, so it is adaptable for the use of on-line detection.

  6. On-line Dynamic Security Assessment in Power Systems

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel

    tools may no longer be feasible, since they are generally based on extensive off-line studies. A core component of an efficient on-line dynamic security assessment is a fast and reliable contingency screening. As part of this thesis a contingency screening method is developed and its performance......The thesis concerns the development of tools and methods for on-line dynamic security assessment (DSA). In a future power system with low-dependence or even independence of fossil fuels, generation will be based to a large extent on noncontrollable renewable energy sources (RES), such as wind...... and solar radiation. Moreover, ongoing research suggests that demand response will be introduced to maintain power balance between generation and consumption at all times. Due to these changes the operating point of the power system will be less predictable and today’s stability and security assessment...

  7. On-line Ramsey Numbers for Paths and Stars

    Directory of Open Access Journals (Sweden)

    Jaroslaw Grytczuk

    2008-08-01

    Full Text Available We study on-line version of size-Ramsey numbers of graphs defined via a game played between Builder and Painter: in one round Builder joins two vertices by an edge and Painter paints it red or blue. The goal of Builder is to force Painter to create a monochromatic copy of a fixed graph H in as few rounds as possible. The minimum number of rounds (assuming both players play perfectly is the on-line Ramsey number r(H of the graph H. We determine exact values of r(H for a few short paths and obtain a general upper bound r(Pn ≤ 4n-7. We also study asymmetric version of this parameter when one of the target graphs is a star Sn with n edges. We prove that r(Sn,H≤n ·e(H when H is any tree, cycle or clique.

  8. Two Types of Designs for On-Line Circulation Systems

    Directory of Open Access Journals (Sweden)

    Rob McGee

    1972-09-01

    Full Text Available On-line circulation systems divide into two types. One type contains records only for charged or otherwise absent items. The other contains a file of records for all titles or volumes in the library collection, regardless of their circulation status. This paper traces differences between the two types, examining different kinds of files and terminals, transaction evidence, the quality of bibliographic data, querying, and the possibility of functions outside circulation. Aspects of both operational and potential systems are considered.

  9. On-line Corrosion Monitoring in District Heating Systems

    DEFF Research Database (Denmark)

    Richter, Sonja; Thorarinsdottir, R.I.; Hilbert, Lisbeth Rischel

    2005-01-01

    The corrosion control in district heating systems is today performed primarily with control of the water quality. The corrosion rate is kept low by assuring low dissolved oxygen concentration, high pH and low conductivity. Corrosion failures can occur, e.g. as a result of unknown oxygen ingress......, precipitation of deposits or crevices. The authors describe methods used for on-line monitoring of corrosion, cover the complications and the main results of a Nordic project....

  10. The new on-line Czech Food Composition Database.

    Science.gov (United States)

    Machackova, Marie; Holasova, Marie; Maskova, Eva

    2013-10-01

    The new on-line Czech Food Composition Database (FCDB) was launched on http://www.czfcdb.cz in December 2010 as a main freely available channel for dissemination of Czech food composition data. The application is based on a complied FCDB documented according to the EuroFIR standardised procedure for full value documentation and indexing of foods by the LanguaL™ Thesaurus. A content management system was implemented for administration of the website and performing data export (comma-separated values or EuroFIR XML transport package formats) by a compiler. Reference/s are provided for each published value with linking to available freely accessible on-line sources of data (e.g. full texts, EuroFIR Document Repository, on-line national FCDBs). LanguaL™ codes are displayed within each food record as searchable keywords of the database. A photo (or a photo gallery) is used as a visual descriptor of a food item. The application is searchable on foods, components, food groups, alphabet and a multi-field advanced search.

  11. Designing effective on-line continuing medical education.

    Science.gov (United States)

    Zimitat, Craig

    2001-03-01

    The Internet, and new information and communication technologies available through the Internet, provides medical educators with an opportunity to develop unique on-line learning environments with real potential to improve physicians' knowledge and effect change in their clinical practice. There are approximately 100 websites offering on-line CME courses in the USA alone. However, few of these CME courses appear to be based on sound educational principles or CME research and may have little chance of achieving the broader goals of CME. The majority of these courses closely resemble their traditional counterparts (e.g. paper-based books are now electronic books) and appear to be mere substitutions for old-technology CME resources. Whilst some CME providers add unique features of the Internet to enrich their websites, they do not employ strategies to optimize the learning opportunities afforded by this new technology. The adoption of adult learning principles, reflective practice and problem-based approaches can be used as a foundation for sound CME course design. In addition, knowledge of Internet technology and the learning opportunities it affords, together with strategies to maintain participation and new assessment paradigms, are all needed for developing online CME. We argue for an evidence-based and strategic approach to the development of on-line CME courses designed to enhance physician learning and facilitate change in clinical behaviour.

  12. Internet Teaching By Style: Profiling the On-line Professor

    Directory of Open Access Journals (Sweden)

    Sharon Strand

    2000-01-01

    Full Text Available The goal of this article is to offer the results of a pilot study which examined the personality type and teaching style preferences of faculty who elected to teach an on-line course. The article will present a description of personality assessments, including the Myers-Briggs Type Indicator (MBTI and Anthony Gregorc's Transaction Ability Inventory used to determine teaching tendencies and styles. In addition, a structured written questionnaire developed by the researchers was used to assess teacher satisfaction with worldwide web-based instruction. Utilizing the results of these psychological assessments, a preliminary analysis of the personal characteristics of college professors who chose to teach on line will be presented. This pilot study found that some preferred teaching styles may be more compatible with the dynamics of distance learning formats. By determining successful teaching styles for on-line courses, we can develop more effective faculty development programs to assist others in successfully transitioning into the cyber-teaching and learning environment.

  13. A note on on-line Ramsey numbers for quadrilaterals

    Directory of Open Access Journals (Sweden)

    Joanna Cyman

    2014-01-01

    Full Text Available We consider on-line Ramsey numbers defined by a game played between two players, Builder and Painter. In each round Builder draws an the edge and Painter colors it either red or blue, as it appears. Builder's goal is to force Painter to create a monochromatic copy of a fixed graph \\(H\\ in as few rounds as possible. The minimum number of rounds (assuming both players play perfectly is the on-line Ramsey number \\(\\widetilde{r}(H\\ of the graph \\(H\\. An asymmetric version of the on-line Ramsey numbers \\(\\widetilde{r}(G,H\\ is defined accordingly. In 2005, Kurek and Ruciński computed \\(\\widetilde{r}(C_3\\. In this paper, we compute \\(\\widetilde{r}(C_4,C_k\\ for \\(3 \\le k \\le 7\\. Most of the results are based on computer algorithms but we obtain the exact value \\(\\widetilde{r}(C_4\\ and do so without the help of computer algorithms.

  14. DEVELOPMENT OF AN ON-LINE COAL WASHABILITY ANALYZER

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Miller; C.L. Lin; G.H. Luttrell; G.T. Adel; Barbara Marin

    2001-06-26

    Washability analysis is the basis for nearly all coal preparation plant separations. Unfortunately, there are no on- line techniques for determining this most fundamental of all coal cleaning information. In light of recent successes at the University of Utah, it now appears possible to determine coal washability on-line through the use of x-ray computed tomography (CT) analysis. The successful development of such a device is critical to the establishment of process control and automated coal blending systems. In this regard, Virginia Tech, Terra Tek Inc., and U.S. coal producers have joined with the University of Utah and to undertake the development of an X-ray CT-based on- line coal washability analyzer with financial assistance from DOE. Each project participant brought special expertise to the project in order to create a new dimension in coal cleaning technology. The project involves development of appropriate software and extensive testing/evaluation of well-characterized coal samples from operating coal preparation plants. Data collected to date suggest that this new technology is capable of serving as a universal analyzer that can not only provide washability analysis, but also particle size distribution analysis, ash analysis, and perhaps pyritic sulfur analysis.

  15. DEVELOPMENT OF AN ON-LINE COAL WASHABILITY ANALYZER

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Miller

    1999-09-30

    Washability analysis is the basis for nearly all coal preparation plant separations. Unfortunately, there are no on-line techniques for determining this most fundamental of all coal cleaning information. In light of recent successes at the University of Utah, it now appears possible to determine coal washability on-line through the use of x-ray computed tomography (CT) analysis. The successful development of such a device is critical to the establishment of process control and automated coal blending systems. In this regard, Virginia Tech, Terra Tek Inc., and several eastern coal companies have joined with the University of Utah and agreed to undertake the development of a x-ray CT-based on-line coal washability analyzer with financial assistance from DOE. The three-year project will cost $594,571, of which 33% ($194,575) will be cost-shared by the participants. The project involves development of appropriate software and extensive testing/evaluation of well-characterized coal samples from operating coal preparation plants. Each project participant brings special expertise to the project which is expected to create a new dimension in coal cleaning technology. Finally, it should be noted that the analyzer may prove to be a universal analyzer capable of providing not only washability analysis, but also particle size distribution analysis, ash analysis and perhaps pyritic sulfur analysis.

  16. Technical Note: Building a combined cyclotron and MRI facility: Implications for interference

    Energy Technology Data Exchange (ETDEWEB)

    Hofman, Mark B. M.; Kuijer, Joost P. A.; Ridder, Jan Willem de; Perk, Lars R.; Verdaasdonk, Rudolf M. [Physics and Medical Technology, VU University Medical Center, Amsterdam 1007 MB (Netherlands) and BV Cyclotron VU, Amsterdam 1081HV (Netherlands)

    2013-01-15

    Purpose: With the introduction of hybrid PET/MRI systems, it has become more likely that the cyclotron and MRI systems will be located close to each other. This study considered the interference between a cyclotron and a superconducting MRI system. Methods: Interactions between cyclotrons and MRIs are theoretically considered. The main interference is expected to be the perturbation of the magnetic field in the MRI due to switching on or off the magnetic field of the cyclotron. MR imaging is distorted by a dynamic spatial gradient of an external inplane magnetic field larger than 0.5-0.04 {mu}T/m, depending on the specific MR application. From the design of a cyclotron, it is expected that the magnetic fringe field at large distances behaves as a magnetic dipolar field. This allows estimation of the full dipolar field and its spatial gradients from a single measurement. Around an 18 MeV cyclotron (Cyclone, IBA), magnetic field measurements were performed on 5 locations and compared with calculations based upon a dipolar field model. Results: At the measurement locations the estimated and measured values of the magnetic field component and its spatial gradients of the inplane component were compared, and found to agree within a factor 1.1 for the magnetic field and within a factor of 1.5 for the spatial gradients of the field. In the specific case of the 18 MeV cyclotron with a vertical magnetic field and a 3T superconducting whole body MR system, a minimum distance of 20 m has to be considered to prevent interference. Conclusions: This study showed that a dipole model is sufficiently accurate to predict the interference of a cyclotron on a MRI scanner, for site planning purposes. The cyclotron and a whole body MRI system considered in this study need to be placed more than 20 m apart, or magnetic shielding should be utilized.

  17. Flash ionisation signature in coherent cyclotron emission from Brown Dwarfs

    CERN Document Server

    Vorgul, Irena

    2016-01-01

    Brown dwarfs form mineral clouds in their atmospheres, where charged particles can produce large-scale discharges in form of lightning resulting in a substantial sudden increase of local ionisation. Brown dwarfs are observed to emit cyclotron radio emission. We show that signatures of strong transient atmospheric ionisation events (flash ionisation) can be imprinted on a pre-existing radiation. Detection of such flash ionisation events will open investigations into the ionisation state and atmospheric dynamics. Such ionisation events can also result from explosion shock waves, bursts or eruptions. We present an analytical model that describes the modulation of a pre-existing electromagnetic radiation by a time-dependent (flash) conductivity that is characteristic for flash ionisation events like lightning. Our conductivity model reproduces the conductivity function derived from observations of Terrestrial Gamma Ray Flashes, and is applicable to astrophysical objects with strong temporal variations in the loca...

  18. Cyclotron resonance maser experiments in a bifilar helical waveguide

    Science.gov (United States)

    Aharony; Drori; Jerby

    2000-11-01

    Oscillator and amplifier cyclotron-resonance-maser (CRM) experiments in a spiral bifilar waveguide are presented in this paper. The slow-wave CRM device employs a low-energy low-current electron beam (2-12 keV, approximately 0.5 A). The pitch angle of the helical waveguide is relatively small; hence, the phase velocity in this waveguide, V(ph) congruent with0.8c (where c is the speed of light), is much faster than the axial velocity of the electrons, V(ez)traveling-wave-tube-type interactions are eliminated in this device. According to the CRM theory, the dominant effect in this operating regime, V(ez)2%). The wide tunable range of this CRM device due to the nondispersive bifilar helix is discussed.

  19. Positron-Cyclotron Maser for the Core Emissions from Pulsars

    CERN Document Server

    Ma, C; Wang, D; Wu, X; Ma, Chun-yu; Mao, Ding-yi; Wang, De-yu; Wu, Xin-ji

    1997-01-01

    We use the cyclotron-maser theory to explain the core emission from the magnetosphere of pulsars. As a kind of direct and efficient maser type of emission, it can give rise to escaping radiation with extremely high brightness temperature and narrow angle with respect to the magnetic axis. We find that the growth rates and real frequencies of the O-mode electromagnetic wave propagating parallel to the magnetic fields depend on the ratio of the plasma frequency $\\omega_p$ and the gyrofrequency $\\omega_b$ rather than the plasma frequency alone, as described by other models. The emission takes place in the region where the magnitude of $\\omega_p/\\omega_b$ is $10^{-2}$. The corresponding altitude is about a few decades of neutron star radius, where the magnetic field strength is about $10^6-10^8 G$. The qualitative spectrum and the lower frequency cut-off of the radio emission is obtained by this model.

  20. Electron Cyclotron Maser Emissions from Evolving Fast Electron Beams

    CERN Document Server

    Tang, J F; Chen, L; Zhao, G Q; Tan, C M

    2016-01-01

    Fast electron beams (FEBs) are common products of solar active phenomena. Solar radio bursts are an important diagnostic tool in the understanding of FEBs as well as the solar plasma environment in which they are propagating along solar magnetic fields. In particular, the evolutions of the energy spectrum and velocity distribution of FEBs due to the interaction with the ambient plasma and field when propagating can significantly influence the efficiency and property of their emissions. In this paper, we discuss some possible evolutions of the energy spectrum and velocity distribution of FEBs due to the energy loss processes and the pitch-angle effect caused by the magnetic field inhomogeneity, and analyze the effects of these evolutions on electron cyclotron maser (ECM) emission, which is one of the most important mechanisms of producing solar radio bursts by FEBs. The results show that the growth rates all decrease with the energy loss factor $Q$, but increase with the magnetic mirror ratio $\\sigma$ as well ...

  1. Cyclotron Resonance Gain for FIR and THz Radiation in Graphene

    CERN Document Server

    Cole, Nightvid

    2016-01-01

    A cyclotron resonance maser source using low-effective-mass conduction electrons in graphene, if successful, would allow for generation of Far Infrared (FIR) and Terahertz (THz) radiation without requiring magnetic fields running into the tens of Tesla. In order to investigate this possibility, we consider a device in which electrons are effectively injected via pumping from the valence band to the conduction band using an infrared (IR) laser source, subsequently gyrate in a magnetic field applied perpendicular to the plane of the graphene, and give rise to gain for a FIR/THz wave crossing the plane of the graphene. A set of integral expressions is derived by assuming that the non-radiative energy loss processes of the electrons can be adequately represented by a damping force proportional and antiparallel to their momentum. Minimal gain may occur at very short electron damping times of hundreds of femtoseconds.

  2. Characteristics of surface sterilization using electron cyclotron resonance plasma

    Science.gov (United States)

    Yonesu, Akira; Hara, Kazufumi; Nishikawa, Tatsuya; Hayashi, Nobuya

    2016-07-01

    The characteristics of surface sterilization using electron cyclotron resonance (ECR) plasma were investigated. High-energy electrons and oxygen radicals were observed in the ECR zone using electric probe and optical emission spectroscopic methods. A biological indicator (BI), Geobacillus stearothermophilus, containing 1 × 106 spores was sterilized in 120 s by exposure to oxygen discharges while maintaining a temperature of approximately 55 °C at the BI installation position. Oxygen radicals and high-energy electrons were found to be the sterilizing species in the ECR region. It was demonstrated that the ECR plasma could be produced in narrow tubes with an inner diameter of 5 mm. Moreover, sterilization tests confirmed that the spores present inside the narrow tube were successfully inactivated by ECR plasma irradiation.

  3. One-electron quantum cyclotron (and implications for cold antihydrogen)

    CERN Document Server

    Gabrielse, G; Odom, B; D'Urso, B

    2001-01-01

    Quantum jumps between Fock states of a one-electron oscillator reveal the quantum limit of a cyclotron accelerator. The states live for seconds when spontaneous emission is inhibited by a factor of 140 within a cylindrical Penning trap cavity. Averaged over hours the oscillator is in thermal equilibrium with black-body photons in the cavity. At 80 mK, quantum jumps occur only when resonant microwave photons are introduced into the cavity, opening a route to improved measurements of the magnetic moments of the electron and positron. The temperature demonstrated is about 60 times lower than the 4.2 K temperature at which charged elementary particles were previously stored. Implications for the production of cold antihydrogen are discussed. (21 refs).

  4. Charge reversal Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Lobodin, Vladislav V; Savory, Joshua J; Kaiser, Nathan K; Dunk, Paul W; Marshall, Alan G

    2013-02-01

    We report the first charge reversal experiments performed by tandem-in-time rather than tandem-in-space MS/MS. Precursor odd-electron anions from fullerene C(60), and even-electron ions from 2,7-di-tert-butylfluorene-9-carboxylic acid and 3,3'-bicarbazole were converted into positive product ions ((-)CR(+)) inside the magnet of a Fourier transform ion cyclotron resonance mass spectrometer. Charge reversal was activated by irradiating precursor ions with high energy electrons or UV photons: the first reported use of those activation methods for charge reversal. We suggest that high energy electrons achieve charge reversal in one step as double electron transfer, whereas UV-activated (-)CR(+) takes place stepwise through two single electron transfers and formally corresponds to a neutralization-reionization ((-)NR(+)) experiment.

  5. Electron cyclotron resonance breakdown studies in a linear plasma system

    Indian Academy of Sciences (India)

    Vipin K Yadav; K Sathyanarayana; D Bora

    2008-03-01

    Electron cyclotron resonance (ECR) plasma breakdown is studied in a small linear cylindrical system with four different gases - hydrogen, helium, argon and nitrogen. Microwave power in the experimental system is delivered by a magnetron at 2.45 ± 0.02 GHz in TE10 mode and launched radially to have extra-ordinary (X) wave in plasma. The axial magnetic field required for ECR in the system is such that the fundamental ECR surface ( = 875.0 G) resides at the geometrical centre of the plasma system. ECR breakdown parameters such as plasma delay time and plasma decay time from plasma density measurements are carried out at the centre using a Langmuir probe. The operating parameters such as working gas pressure (1 × 10-5 -1 × 10-2 mbar) and input microwave power (160{800 W) are varied and the corresponding effect on the breakdown parameters is studied. The experimental results obtained are presented in this paper.

  6. On-line charge breeding using ECRIS and EBIS

    Science.gov (United States)

    Vondrasek, Richard

    2016-06-01

    The efficient and rapid production of a high-quality, pure beam of highly charged ions is at the heart of any radioactive ion beam facility. Whether an electron cyclotron resonance (ECR) ion source or an electron beam ion source (EBIS) is used to produce these highly charged ions, their operating characteristics will set the boundaries on the range of experiments which can be performed. In addition, time structure and duty cycle have to be considered when defining the operating parameters of the accelerator system as a whole. At Argonne National Laboratory (ANL), an ECR charge breeder was developed as part of the Californium Rare Ion Breeder Upgrade (CARIBU) program. The charge breeding efficiency and high charge state production of the source is at the forefront of ECR charge breeders, but its overall performance as part of the accelerator system is limited by pervasive background and relatively long breeding times. As such, an EBIS charge breeder has been developed and is running in an off-line configuration. It has already demonstrated good breeding efficiencies, shorter residence times, and reduced background and is scheduled to replace the ECR charge breeder in late 2015. The resultant change in duty cycle and time structure necessitates changes to the overall operation of the facility. The experiences with these breeders, as well as from several other facilities which already utilize an ECR or EBIS for charge breeding, help to define the operational characteristics of each technology - their strengths, their weaknesses, and the possible paths to improvement.

  7. Conceptual design of CFETR electron cyclotron wave system

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yunying, E-mail: yytang@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Shushanhu Road 350, Hefei 230031, Anhui (China); University of Science and Technology of China, Jinzhai Road 96, Hefei 230026, Anhui (China); Wang, Xiaojie; Liu, Fukun; Zhang, Liyuan; Wei, Wei; Xu, Handong; Xu, Weiye; Wu, Dajun; Feng, Jianqiang [Institute of Plasma Physics, Chinese Academy of Sciences, Shushanhu Road 350, Hefei 230031, Anhui (China)

    2015-05-15

    Highlights: • The conceptual design of 170 GHz/20 MW electron cyclotron wave system was introduced. • The layout of RF sources was given. • The design and layout of transmission lines were shown and series of microwave components were introduced. • The structure of launcher was described in detail. • By the optic calculation and optimization of RF propagation inside the launcher, the quasi-optical parameters for launcher design were given. And then temperature distribution and thermal-stress of the injection mirror were analyzed. - Abstract: China Fusion Engineering Test Reactor (CFETR) is a test tokamak which is built for magnetically confined fusion plasma experiments. The electron cyclotron (EC) wave system of CFETR is designed to inject 20 MW RF power into the plasma for heating and current drive (H&CD) applications. The EC wave system consists of RF sources, twenty transmission lines (TLs) and one equatorial launcher. RF sources contain twenty gyrotrons with the output power 1 MW. There are series of microwave components distributed along the TL and the percentage of power losses of each TL is about 8.7%. In the equatorial launcher, five RF beams are injected into one focusing mirror and then reflected to the plasma via one injection mirror. The focusing mirror is spherical to focus Gaussian beam and the injection mirror which is flat can steer in the toroidal direction. After optic calculation and optimization, all the quasi-optical parameters for launcher design are given. Combining with the thermal stress analysis, the chosen inner diameter of water channel of injection mirror is 12 mm and the suggested water velocity is 3 m/s.

  8. Response of thermal ions to electromagnetic ion cyclotron waves

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, B.J. [Johns Hopkins Univ., Laurel, MD (United States); Fuselier, S.A. [Lockheed Palo Alto Research Lab., CA (United States)

    1994-10-01

    Electromagnetic ion cyclotron waves generated by 10-50 keV protons in the Earth`s equatorial magnetosphere will interact with the ambient low-energy ions also found in this region. The authors examine H{sup +} and He{sup +} distribution functions from {approx} 1 to 160 eV using the Hot Plasma Composition Experiment instrument on AMPTE/CCE to investigate the thermal ion response to the waves. A total of 48 intervals were chosen on the basis of electromagnetic ion cyclotron (EMIC) wave activity: 24 with prevalent EMIC waves and 24 with no EMIC waves observed on the orbit. There is a close correlation between EMIC waves and perpendicularly heated ion distributions. For protons the perpendicular temperature increase is modest, about 5 eV, and is always observed at 90{degrees} pitch angles. This is consistent with a nonresonant interaction near the equator. By contrast, He{sup +} temperatures during EMIC wave events averaged 35 eV and sometimes exceeded 100 eV, indicating stronger interaction with the waves. Furthermore, heated He{sup +} ions have X-type distributions with maximum fluxes occurring at pitch angles intermediate between field-aligned and perpendicular directions. The X-type He{sup +} distributions are consistent with a gyroresonant interaction off the equator. The concentration of He{sup +} relative to H{sup +} is found to correlate with EMIC wave activity, but it is suggested that the preferential heating of He{sup +} accounts for the apparent increase in relative He{sup +} concentration by increasing the proportion of He{sup +} detected by the ion instrument. 35 refs., 8 figs., 1 tab.

  9. Flash ionization signature in coherent cyclotron emission from brown dwarfs

    Science.gov (United States)

    Vorgul, I.; Helling, Ch.

    2016-05-01

    Brown dwarfs (BDs) form mineral clouds in their atmospheres, where charged particles can produce large-scale discharges in the form of lightning resulting in substantial sudden increase of local ionization. BDs are observed to emit cyclotron radio emission. We show that signatures of strong transient atmospheric ionization events (flash ionization) can be imprinted on a pre-existing radiation. Detection of such flash ionization events will open investigations into the ionization state and atmospheric dynamics. Such events can also result from explosion shock waves, material outbursts or (volcanic) eruptions. We present an analytical model that describes the modulation of a pre-existing electromagnetic radiation by a time-dependent (flash) conductivity that is characteristic for flash ionization events like lightning. Our conductivity model reproduces the conductivity function derived from observations of terrestrial gamma-ray flashes, and is applicable to astrophysical objects with strong temporal variations in the local ionization, as in planetary atmospheres and protoplanetary discs. We show that the field responds with a characteristic flash-shaped pulse to a conductivity flash of intermediate intensity. More powerful ionization events result in smaller variations of the initial radiation, or in its damping. We show that the characteristic damping of the response field for high-power initial radiation carries information about the ionization flash magnitude and duration. The duration of the pulse amplification or the damping is consistently shorter for larger conductivity variations and can be used to evaluate the intensity of the flash ionization. Our work suggests that cyclotron emission could be probe signals for electrification processes inside BD atmosphere.

  10. Intelligent Low-level RF System by Non-destructive Beam Monitoring Device for Cyclotrons

    CERN Document Server

    Malafeh, M S Sharifi Asadi; Afarideh, H; Chai, J S

    2015-01-01

    The project of a10MeV PET cyclotron accelerator for medical diagnosis and treatment was started at Amirkabir University of Technology in 2012. The low-level RF system of cyclotron accelerator is designed to stabilize acceleration voltage and control the resonance frequency of the cavity. In this work Intelligent Low Level Radio Frequency Circuit or ILLRF suitable for Most of the AVF cyclotron accelerators was designed by the beam monitoring device and narrow band tunable band-pass filter. In this design, for the RF phase detection does not need to signal processing by microcontroller

  11. The physics design of magnet in 14 MeV cyclotron

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The 14 MeV, 400 μA compact cyclotron is under construction at China Institute of Atomic Energy (CIAE). The design of main magnet and the result of beam dynamics in the cyclotron will be described in this paper, including the choice of main parameters of magnet, the method of shimming isochronous field in the compact cyclotron and optimization of the magnetic field in central region. The beam will be accelerated to 14.6 MeV by optimizing the magnet structure.

  12. BOOK REVIEW: ON-LINE EDUCATION: AN EMANCIPATING VISION

    Directory of Open Access Journals (Sweden)

    Reviewed by Dr. Abdullah KUZU

    2006-04-01

    Full Text Available ON-LINE EDUCATION: AN EMANCIPATING VISION Written by Margarita Victoria Gomez Publisher: Cortez Editora ISBN 85-249-1062-3 São Paulo, Brazil, July 2004. Reviewed by Ricardo Romo TORRES Manuel Moreno Castaneda Maria del Sol Orozco Aguirre Universidad de Guadalajara Virtual MEXICO http://www.udgvirtual.udg.mx "On-line Education " is a book that meets the challenge to present itself as an unfinished text. In addition to demanding an active participation of the reader, it requires a predisposition to complete it through an also inconclusive dialogue. Among its goals we can find the search for education networks that remain under constant reconstruction, maintaining the emancipative vision as an imperative for the reconfiguration, as a constituted tissue for the scaffolding of subjects who impress,imagine, think and have a will. The unfinished part is presented in the following paragraph: "Similar to Babel according to Borges, knowledge is the product of a hazard in which fiction is the universe and where, out of fear of its multiple combinations, individual texts constitute an unfinished tale. In this labyrinth-shaped universe, the mirror and the recurrence do not allow finding the way out" page 134. The sense of being of man within a planetary community is framed by the ontological condition of conclusiveness; the requirement of being more, however, as well. This more is guided by the need for dialogue with others in terms of the opening and maintaining an unconcluded dialogue. The idea of a web or network leads to an articulating demand within the context of the category of wholeness. Based on this category, we will be able to present a reticulum of concepts where we can find included the web, subjectivity, identity, experience, mediation and, of course, digital literacy. This reticulum results in a concept of identified education with a condensed arrival point to something that the author defines as 'the pedagogy of virtuality'. The author is

  13. The Means-End Approach to Understanding Customer Values of a On-Line Newspaper

    Directory of Open Access Journals (Sweden)

    André Luiz Maranhão de Souza Leão

    2007-01-01

    Full Text Available Customer value is understood as one of the constructs that best explains consumer decision making. Its proposal is to understand how consumers translate product or service characteristics and consequences of use into personal self-relevant values. The means-end theory is a way of systematically thinking in this hierarchicalrepresentation. The most commonly used method to achieve means-end chains is laddering. This theory and method were used to understand customer values of an important on-line Brazilian newspaper, which is an innovative approach, since on-line laddering is uncommon. The findings indicate that values related to goals of a personal nature are the most important ones. However, other values indicate the increase of the public man pointing to an alternative vision of what is commonly thought of as the contemporary isolated and selfish human. Academic research could benefit from a broader understanding and use of the means-end theory and laddering on the Web. Future research for managerial practices is warranted in areas such as segmentation, satisfaction measuring and customer value reevaluation, in addition to copy tests.

  14. Magnetostrictive Alternator

    Science.gov (United States)

    Dyson, Rodger; Bruder, Geoffrey

    2013-01-01

    This innovation replaces the linear alternator presently used in Stirling engines with a continuous-gradient, impedance-matched, oscillating magnetostrictive transducer that eliminates all moving parts via compression, maintains high efficiency, costs less to manufacture, reduces mass, and eliminates the need for a bearing system. The key components of this new technology are the use of stacked magnetostrictive materials, such as Terfenol-D, under a biased magnetic and stress-induced compression, continuous-gradient impedance-matching material, coils, force-focusing metallic structure, and supports. The acoustic energy from the engine travels through an impedancematching layer that is physically connected to the magnetostrictive mass. Compression bolts keep the structure under compressive strain, allowing for the micron-scale compression of the magnetostrictive material and eliminating the need for bearings. The relatively large millimeter displacement of the pressure side of the impedance-matching material is reduced to micron motion, and undergoes stress amplification at the magnetostrictive interface. The alternating compression and expansion of the magnetostrictive material creates an alternating magnetic field that then induces an electric current in a coil that is wound around the stack. This produces electrical power from the acoustic pressure wave and, if the resonant frequency is tuned to match the engine, can replace the linear alternator that is commonly used.

  15. Growing Alternatives

    DEFF Research Database (Denmark)

    Bagger-Petersen, Mai Corlin

    2014-01-01

    From 2014, Anhui Province will pilot a reform of the residential land market in China, thus integrating rural Anhui in the national housing market. In contrast, artist and activist Ou Ning has proposed the Bishan time money currency, intending to establish an alternative economic circuit in Bishan...

  16. Alternative Treatments

    Science.gov (United States)

    ... triglyceride (fat) produced by processing coconut oil or palm kernel oil. The body breaks down caprylic acid into substances called “ketone bodies.” The theory behind Axona is that the ketone bodies derived from caprylic acid may provide an alternative energy source for brain cells that have lost ...

  17. A Refreshable, On-line Cache for HST Data Retrieval

    Science.gov (United States)

    Fraquelli, Dorothy A.; Ellis, Tracy A.; Ridgaway, Michael; DPAS Team

    2016-01-01

    We discuss upgrades to the HST Data Processing System, with an emphasis on the changes Hubble Space Telescope (HST) Archive users will experience. In particular, data are now held on-line (in a cache) removing the need to reprocess the data every time they are requested from the Archive. OTFR (on the fly reprocessing) has been replaced by a reprocessing system, which runs in the background. Data in the cache are automatically placed in the reprocessing queue when updated calibration reference files are received or when an improved calibration algorithm is installed. Data in the on-line cache are expected to be the most up to date version. These changes were phased in throughout 2015 for all active instruments.The on-line cache was populated instrument by instrument over the course of 2015. As data were placed in the cache, the flag that triggers OTFR was reset so that OTFR no longer runs on these data. "Hybrid" requests to the Archive are handled transparently, with data not yet in the cache provided via OTFR and the remaining data provided from the cache. Users do not need to make separate requests.Users of the MAST Portal will be able to download data from the cache immediately. For data not in the cache, the Portal will send the user to the standard "Retrieval Options Page," allowing the user to direct the Archive to process and deliver the data.The classic MAST Search and Retrieval interface has the same look and feel as previously. Minor changes, unrelated to the cache, have been made to the format of the Retrieval Options Page.

  18. On-line learning algorithms for locally recurrent neural networks.

    Science.gov (United States)

    Campolucci, P; Uncini, A; Piazza, F; Rao, B D

    1999-01-01

    This paper focuses on on-line learning procedures for locally recurrent neural networks with emphasis on multilayer perceptron (MLP) with infinite impulse response (IIR) synapses and its variations which include generalized output and activation feedback multilayer networks (MLN's). We propose a new gradient-based procedure called recursive backpropagation (RBP) whose on-line version, causal recursive backpropagation (CRBP), presents some advantages with respect to the other on-line training methods. The new CRBP algorithm includes as particular cases backpropagation (BP), temporal backpropagation (TBP), backpropagation for sequences (BPS), Back-Tsoi algorithm among others, thereby providing a unifying view on gradient calculation techniques for recurrent networks with local feedback. The only learning method that has been proposed for locally recurrent networks with no architectural restriction is the one by Back and Tsoi. The proposed algorithm has better stability and higher speed of convergence with respect to the Back-Tsoi algorithm, which is supported by the theoretical development and confirmed by simulations. The computational complexity of the CRBP is comparable with that of the Back-Tsoi algorithm, e.g., less that a factor of 1.5 for usual architectures and parameter settings. The superior performance of the new algorithm, however, easily justifies this small increase in computational burden. In addition, the general paradigms of truncated BPTT and RTRL are applied to networks with local feedback and compared with the new CRBP method. The simulations show that CRBP exhibits similar performances and the detailed analysis of complexity reveals that CRBP is much simpler and easier to implement, e.g., CRBP is local in space and in time while RTRL is not local in space.

  19. Design of Spiral Inflector and Central Region for a Medical Cyclotron

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    CYCIAE-14 is a medical cyclotron designed to accelerate H- ions and extract protons, and it adopts the external ion source and axial injection line. The spiral inflector and the central region are the important

  20. Electrostatic electron cyclotron instabilities near the upper hybrid layer due to electron ring distributions

    Science.gov (United States)

    Eliasson, B.; Speirs, D. C.; Daldorff, L. K. S.

    2016-09-01

    A theoretical study is presented of the electrostatic electron cyclotron instability involving Bernstein modes in a magnetized plasma. The presence of a tenuous thermal ring distribution in a Maxwellian plasma decreases the frequency of the upper hybrid branch of the electron Bernstein mode until it merges with the nearest lower branch with a resulting instability. The instability occurs when the upper hybrid frequency is somewhat above the third, fourth, and higher electron cyclotron harmonics, and gives rise to a narrow spectrum of waves around the electron cyclotron harmonic nearest to the upper hybrid frequency. For a tenuous cold ring distribution together with a Maxwellian distribution an instability can take place also near the second electron cyclotron harmonic. Noise-free Vlasov simulations are used to assess the theoretical linear growth-rates and frequency spectra, and to study the nonlinear evolution of the instability. The relevance of the results to laboratory and ionospheric heating experiments is discussed.

  1. High performance computation on beam dynamics problems in high intensity compact cyclotrons

    Institute of Scientific and Technical Information of China (English)

    ADELMANN; Andreas

    2011-01-01

    This paper presents the research progress in the beam dynamics problems for future high intensity compact cyclotrons by utilizing the state-of-the-art high performance computation technology. A "Start-to-Stop" model, which includes both the interaction of the internal particles of a single bunch and the mutual interaction of neighboring multiple bunches in the radial direction, is established for compact cyclotrons with multi-turn extraction. This model is then implemented in OPAL-CYCL, which is a 3D object-oriented parallel code for large scale particle simulations in cyclotrons. In addition, to meet the running requirement of parallel computation, we have constructed a small scale HPC cluster system and tested its performance. Finally, the high intensity beam dynamics problems in the 100 MeV compact cyclotron, which is being constructed at CIAE, are studied using this code and some conclusions are drawn.

  2. Cyclotron-based nuclear science. Progress report, April 1, 1979-March 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    Research at the cyclotron institute is summarized. These major areas are covered: nuclear structure; nuclear reactions and scattering; polarization studies; interdisciplinary nuclear science; instrumentation and systems development; and publications. (GHT)

  3. Efficient and Secure Comparison for On-Line Auctions

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Krøigaard, Mikkel; Geisler, Martin Joakim

    2007-01-01

    We propose a protocol for secure comparison of integers based on homomorphic encryption. We also propose a homomorphic encryption scheme that can be used in our protocol and makes it more efficient than previous solutions. Our protocol is well-suited for application in on-line auctions, both...... with respect to functionality and performance. It minimizes the amount of information bidders need to send, and for comparison of 16 bit numbers with security based on 1024 bit RSA (executed by two parties), our implementation takes 0.28 seconds including all computation and communication. Using precomputation...

  4. On-line Monitoring and Active Control for Transformer Noise

    Science.gov (United States)

    Liang, Jiabi; Zhao, Tong; Tian, Chun; Wang, Xia; He, Zhenhua; Duan, Lunfeng

    This paper introduces the system for on-line monitoring and active noise control towards the transformer noise based on LabVIEW and the hardware equipment including the hardware and software. For the hardware part, it is mainly focused on the composition and the role of hardware devices, as well as the mounting location in the active noise control experiment. And the software part introduces the software flow chats, the measurement and analysis module for the sound pressure level including A, B, C weighting methods, the 1/n octave spectrum and the power spectrum, active noise control module and noise data access module.

  5. Robust Control Methods for On-Line Statistical Learning

    Directory of Open Access Journals (Sweden)

    Capobianco Enrico

    2001-01-01

    Full Text Available The issue of controlling that data processing in an experiment results not affected by the presence of outliers is relevant for statistical control and learning studies. Learning schemes should thus be tested for their capacity of handling outliers in the observed training set so to achieve reliable estimates with respect to the crucial bias and variance aspects. We describe possible ways of endowing neural networks with statistically robust properties by defining feasible error criteria. It is convenient to cast neural nets in state space representations and apply both Kalman filter and stochastic approximation procedures in order to suggest statistically robustified solutions for on-line learning.

  6. On-line matrix addition for detecting aerosol particles

    Institute of Scientific and Technical Information of China (English)

    ZHOU; Liuzhu; ZHU; Yuan; GUO; Xiaoyong; ZHAO; Wenwu; ZHENG; Haiyang; Gu; Xuejun; FANG; Li; ZHANG; Weijun

    2006-01-01

    Single aerosol particles were measured by matrix-assisted laser desorption/ionization (MALDI) with an aerosol time-of-flight mass spectrometer (ATOFMS). The inlet to the ATOFMS was coupled with an evaporation/condensation flow cell that allowed matrix addition by condensation onto the particles. The coated particles entered the ion source through three-stage differentially pumped capillary inlet and were then ionized by a focused 266 nm Nd:YAG laser. The mass spectra and aerodynamic size of the single particles can be obtained simultaneously. The on-line matrix addition technique makes it possible to identify biological aerosols in real-time.

  7. On-line Adaptive Radiation Treatment of Prostate Cancer

    Science.gov (United States)

    2008-01-01

    volume (GTV), mandible, rainstem, parotids , and lymph nodes. Another physician repeated he contouring on all planning and on-line images...computed entation. Note the consistency of delineation of gross olume; light blue, nodes; purple, parotid glands; green,k com ostregicomp urs on e...0.9 1.0 Mandible D S C in de x Patient # 1 2 3 4 5 6 7 0.5 0.6 0.7 0.8 0.9 1.0 Left Parotid D S C in de x Patient # Fig. 6. Dice similarity

  8. Enhancing Learner Autonomy in an On-line Editing Programme

    Directory of Open Access Journals (Sweden)

    Hebe Wong

    2011-09-01

    Full Text Available Little (1999 argues that in formal educational contexts, “the basis of learner autonomy is acceptance of responsibility for one’s own learning” (p.11. An autonomous learner takes responsibility for various aspects of learning (Benson & Voller, 1997; Holec, 1981. This study examines how learner autonomy opportunities were provided at various stages of writing in an on-line editing programme for a group of electronic engineering students and how the students took charge of their language learning when receiving feedback on their technical writing. The impact on their own learning effectiveness of the decisions students made is also discussed.

  9. On-line Measurements of Settling Charateristics in Activated Sludge

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Larsen, Torben

    1997-01-01

    An on-line settling column for measuring the dynamic variations of settling velocity of activated sludge has been developed. The settling column is automatic and self-cleansing insuring continuous and reliable measurements. The settling column was tested on sludge from a batch reactor where sucrose...... was added as an impulse to activated sludge. The continuous measurement of settling velocity revealed a highly dynamic response after the sucrose was added. The result were verified with simultaneous measurement of the initial settling rate. A 200 hour experiment showed variations in settling velocity...

  10. Lower Bounds and Semi On-line Multiprocessor Scheduling

    Directory of Open Access Journals (Sweden)

    T.C. Edwin Cheng

    2003-10-01

    Full Text Available We are given a set of identical machines and a sequence of jobs from which we know the sum of the job weights in advance. The jobs have to be assigned on-line to one of the machines and the objective is to minimize the makespan. An algorithm with performance ratio 1.6 and a lower bound of 1.5 is presented. This improves recent results by Azar and Regev who published an algorithm with performance ratio 1.625 for the less general problem that the optimal makespan is known in advance.

  11. TELCAL: The On-line Calibration Software for ALMA

    Science.gov (United States)

    Broguière, D.; Lucas, R.; Pardo, J.; Roche, J.-C.

    2011-07-01

    The ALMA on-line calibration regroups all the operations needed to maintain the ALMA interferometer optimally tuned to successfully execute the planned observations. The results of the calibrations are used in quasi-real time by the ALMA Control System. Since the first ALMA antennas were put into operation in 2009, TELCAL has been used for all the basic calibration operations and is still being improved following the project advancement. We describe here the calibrations done by TELCAL, its relationships with the other ALMA software subsystems and, briefly, the architecture of the software based on CORBA.

  12. On-line yields obtained with the ISOLDE RILIS

    Energy Technology Data Exchange (ETDEWEB)

    Koester, U. E-mail: ulli.koster@cern.ch; Fedoseyev, V.N.; Andreyev, A.N.; Bergmann, U.C.; Catherall, R.; Cederkaell, J.; Dietrich, M.; De Witte, H.; Fedorov, D.V.; Fraile, L.; Franchoo, S.; Fynbo, H.; Georg, U.; Giles, T.; Gorska, M.; Hannawald, M.; Huyse, M.; Joinet, A.; Jonsson, O.C.; Kratz, K.L.; Kruglov, K.; Lau, Ch.; Lettry, J.; Mishin, V.I.; Oinonen, M.; Partes, K.; Peraejaervi, K.; Pfeiffer, B.; Ravn, H.L.; Seliverstov, M.D.; Thirolf, P.; Van de Vel, K.; Van Duppen, P.; Van Roosbroeck, J.; Weissman, L

    2003-05-01

    The ISOLDE resonance ionization laser ion source (RILIS) allows to ionize efficiently and selectively many metallic elements. In recent yield surveys and on-line experiments with the ISOLDE RILIS we observed {sup 23-34}Mg, {sup 26-34}Al, {sup 98-132}Cd, {sup 149}Tb, {sup 155-177}Yb, {sup 179-200}Tl, {sup 183-215}Pb and {sup 188-218}Bi. The obtained yields are presented together with measured release parameters which allow to extrapolate the release efficiency towards more exotic (short-lived) nuclides of the same elements.

  13. Adaptive calibration method with on-line growing complexity

    Directory of Open Access Journals (Sweden)

    Šika Z.

    2011-12-01

    Full Text Available This paper describes a modified variant of a kinematical calibration algorithm. In the beginning, a brief review of the calibration algorithm and its simple modification are described. As the described calibration modification uses some ideas used by the Lolimot algorithm, the algorithm is described and explained. Main topic of this paper is a description of a synthesis of the Lolimot-based calibration that leads to an adaptive algorithm with an on-line growing complexity. The paper contains a comparison of simple examples results and a discussion. A note about future research topics is also included.

  14. Integrated sensor array for on-line monitoring micro bioreactors

    NARCIS (Netherlands)

    Krommenhoek, Erik Eduard

    2007-01-01

    In this thesis the development of a microbioreactor array with integrated sensoss suitable for on-line screening of micro organisms is described. Therefore, an array of 2 micro bioreactors compatible with the 96-well microtiterplate format has been made and tested. The developed system was shown to 

  15. Molecularly imprinted polymers for on-line extraction techniques.

    Science.gov (United States)

    Moein, Mohammad M; Abdel-Rehim, Mohamed

    2015-01-01

    Recent years have seen an increasing interest in the use of molecularly imprinted polymers (MIPs) as a sorbent for different extraction methods and this is due to its high selectivity. The MIP is designed to show specificity for the analyte of interest. Moreover, MIPs show physical robustness, resistance to high temperatures and pressures, and stability in the presence of acids, bases and a wide range of organic solvents. In the present article, various novel sample preparation techniques which MIPs applied as sorbent and on-line connected with analytical instruments were highlighted and discussed. The future aspects of MIPs as well were described.

  16. Infra red active modes due to coupling of cyclotron excitation and LO phonons in polar semiconductor

    Science.gov (United States)

    Agrawal, Ratna; Dubey, Swati; Ghosh, S.

    2013-06-01

    Effects of free carrier concentration, external magnetic field and Callen effective charge on infra red active modes in a polar semiconductor have been analytically investigated using simple harmonic oscillator model. Callen effective charge considerably enhances reflectivity and shifts minima towards lower values of energy. Presence of magnetic field leads towards the coupling of collective cyclotron excitations with LO phonon giving rise to maximum reflectivity whereas cyclotron resonance absorption results into minimum reflectivity.

  17. Bi-directional Alfv\\'en Cyclotron Instabilities in the Mega-Amp Spherical Tokamak

    CERN Document Server

    Sharapov, S E; Akers, R; Ayed, N Ben; Cecconello, M; Cook, J W C; Cunningham, G; Verwichte, E; Tea, the MAST

    2014-01-01

    Alfv\\'en cyclotron instabilities excited by velocity gradients of energetic beam ions were investigated in MAST experiments with super-Alfv\\'enic NBI over a wide range of toroidal magnetic fields from ~0.34 T to ~0.585 T. In MAST discharges with high magnetic field, a discrete spectrum of modes in the sub-cyclotron frequency range is excited toroidally propagating counter to the beam and plasma current (toroidal mode numbers n < 0).

  18. Optically detected cyclotron resonance in a single GaAs/AlGaAs heterojunction

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, Gregor

    2011-09-23

    Optically detected far-infrared cyclotron resonance (FIR-ODCR) in GaAs/AlGaAs HJs is interpreted in the frame of an exciton-dissociation mechanism. It is possible to explain the ODR mechanism by an exciton drag, mediated by ballistically propagating phonons. Furthermore, very narrow resonances are presented and realistic electron mobility values can be calculated. The exceptionally narrow ODCRs allow to measure conduction-band nonparabolicity effects and resolve satellite resonances, close to the main cyclotron resonance line.

  19. Extraction and diagnostic systems of the CIME cyclotron for SPIRAL project; Systemes d`ejection et de diagnostics du cyclotron CIME du projet SPIRAL

    Energy Technology Data Exchange (ETDEWEB)

    Bibet, D.; Bourgarel, M.P. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Laune, B.; Malard, M.; Mormiche, M.; Serafini, A.; Szott, Ph. [Services Techniques, Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

    1999-11-01

    The extraction of the CIME cyclotron of the SPIRAL R.I.B. facility is composed of two electrostatic deflectors followed by two magnetostatic channels. For the diagnostics, a radial probe carrying a plastic scintillator for the radioactive beams, has been built, as well as dedicated probes in front of each of the channels. A set of 15 electrostatic pick up probes will enable the phase tuning for the stable beams. All these elements have been built and fully tested at the IPN, prior to there final installation on the CIME cyclotron. (authors) 4 figs.

  20. Evaluation of the latent radiation dose from the activated radionuclides in a cyclotron vault

    Science.gov (United States)

    Kim, Hyunduk; Cho, Gyuseong; Kim, Sun A.; Kang, Bo Sun

    2015-02-01

    The production of short-lived radioisotopes for the synthesis of radiopharmaceuticals typically takes advantage of a cyclotron that accelerates a proton beam up to a few tens of MeV. The number of cyclotrons has been continuously increasing since the first operation of the MC-50 for the production of radiopharmaceuticals at the Korea Institute of Radiological & Medical Sciences (KIRAMS) in 1986, and currently 35 cyclotrons are under operation throughout the nation. As the number of operating cyclotrons has increased, concerns about radiation safety for the persons who are working at the facilities and dwelling in the vicinity of the facilities are becoming important issues. Radiation that could emit a time-dependent dose was shown to exist in a cyclotron vault after its shutdown. The calculation of the latent radiation dose rate was performed by using the MCNPX and the FISPACT. The calculated results for the activated long-lived radioisotopes in the concrete wall and the structural components of the cyclotron facility were compared with the measured data that were obtained by using gamma-ray spectroscopy with a HPGe detector.

  1. Influence of injection beam emittance on beam transmission efficiency in a cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Kurashima, Satoshi, E-mail: kurashima.satoshi@jaea.go.jp; Kashiwagi, Hirotsugu; Miyawaki, Nobumasa; Yoshida, Ken-Ichi; Okumura, Susumu [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2014-02-15

    The JAEA AVF cyclotron accelerates various kinds of high-energy ion beams for research in biotechnology and materials science. Beam intensities of an ion species of the order of 10{sup −9}–10{sup −6} ampere are often required for various experiments performed sequentially over a day. To provide ion beams with sufficient intensity and stability, an operator has to retune an ion source in a short time. However, the beam intensity downstream of the cyclotron rarely increases in proportion to the intensity at the ion source. To understand the cause of this beam behavior, transmission efficiencies of a {sup 12}C{sup 5+} beam from an electron cyclotron resonance ion source to the cyclotron were measured for various conditions of the ion source. Moreover, a feasible region for acceleration in the emittance of the injection beam was clarified using a transverse-acceptance measuring system. We confirmed that the beam emittance and profile were changed depending on the condition of the ion source and that matching between the beam emittance and the acceptance of the cyclotron was degraded. However, after fine-tuning to improve the matching, beam intensity downstream of the cyclotron increased.

  2. Multi-Species Test of Ion Cyclotron Resonance Heating at High Altitudes

    Science.gov (United States)

    Persoon, A. M.; Peterson, W. K.; Andre, M.; Chang, T.; Gurnett, D. A.; Retterer, J. M.; Crew, G. B.

    1997-01-01

    Observations of ion distributions and plasma waves obtained by the Dynamics Explorer 1 satellite in the high-altitude, nightside auroral zone are used to study ion energization for three ion species. A number of theoretical models have been proposed to account for the transverse heating of these ion populations. One of these, the ion cyclotron resonance heating (ICRH) mechanism, explains ion conic formation through ion cyclotron resonance with broadband electromagnetic wave turbulence in the vicinity of the characteristic ion cyclotron frequency. The cyclotron resonant heating of the ions by low-frequency electromagnetic waves is an important energy source for the transport of ions from the ionosphere to the magnetosphere. In this paper we test the applicability of the ICRH mechanism to three simultaneously heated and accelerated ion species by modelling the ion conic formation in terms of a resonant wave-particle interaction in which the ions extract energy from the portion of the broadband electromagnetic wave spectrum which includes the ion cyclotron frequency. Using a Monte Carlo technique we evaluate the ion heating produced by the electromagnetic turbulence at low frequencies and find that the wave amplitudes near the ion cyclotron frequencies are sufficient to explain the observed ion energies.

  3. Increased Cortical Thickness in Professional On-Line Gamers

    Science.gov (United States)

    Hyun, Gi Jung; Shin, Yong Wook; Kim, Bung-Nyun; Cheong, Jae Hoon; Jin, Seong Nam

    2013-01-01

    Objective The bulk of recent studies have tested whether video games change the brain in terms of activity and cortical volume. However, such studies are limited by several factors including cross-sectional comparisons, co-morbidity, and short-term follow-up periods. In the present study, we hypothesized that cognitive flexibility and the volume of brain cortex would be correlated with the career length of on-line pro-gamers. Methods High-resolution magnetic resonance scans were acquired in twenty-three pro-gamers recruited from StarCraft pro-game teams. We measured cortical thickness in each individual using FreeSurfer and the cortical thickness was correlated with the career length and the performance of the pro-gamers. Results Career length was positively correlated with cortical thickness in three brain regions: right superior frontal gyrus, right superior parietal gyrus, and right precentral gyrus. Additionally, increased cortical thickness in the prefrontal cortex was correlated with winning rates of the pro-game league. Increased cortical thickness in the prefrontal and parietal cortices was also associated with higher performance of Wisconsin Card Sorting Test. Conclusion Our results suggest that in individuals without pathologic conditions, regular, long-term playing of on-line games is associated with volume changes in the prefrontal and parietal cortices, which are associated with cognitive flexibility. PMID:24474988

  4. Polar On-Line Acquisition Relay and Transmission System (POLARATS)

    Energy Technology Data Exchange (ETDEWEB)

    Yuracko, K.

    2004-07-15

    POLARATS (Polar On-Line Acquisition Relay And Transmission System) is being developed by YAHSGS LLC (YAHSGS) and Oak Ridge National Laboratory (ORNL) to provide remote, unattended monitoring of environmental parameters under harsh environmental conditions. In particular, instrumental design and engineering is oriented towards protection of human health in the Arctic, and with the additional goal of advancing Arctic education and research. POLARATS will obtain and transmit environmental data from hardened monitoring devices deployed in locations important to understanding atmospheric and aquatic pollutant migration as it is biomagnified in Arctic food chains. An Internet- and personal computer (PC)-based educational module will provide real time sensor data, on-line educational content, and will be integrated with workbooks and textbooks for use in middle and high school science programs. The educational elements of POLARATS include an Internet-based educational module that will instruct students in the use of the data and how those data fit into changing Arctic environments and food chains. POLARATS will: (1) Enable students, members of the community, and scientific researchers to monitor local environmental conditions in real time over the Internet; and (2) Provide additional educational benefits through integration with middle- and high-school science curricula. Information will be relayed from POLARATS devices to classrooms and libraries along with custom-designed POLARATS teaching materials that will be integrated into existing curricula to enhance the educational benefits realized from the information obtained.

  5. Fully On-line Introductory Physics with a Lab

    Science.gov (United States)

    Schatz, Michael

    We describe the development and implementation of a college-level introductory physics (mechanics) course and laboratory that is suited for both on-campus and on-line environments. The course emphasizes a ``Your World is Your Lab'' approach whereby students first examine and capture on video (using cellphones) motion in their immediate surroundings, and then use free, open-source software both to extract data from the video and to apply physics principles to build models that describe, predict, and visualize the observations. Each student reports findings by creating a video lab report and posting it online; these video lab reports are then distributed to the rest of the class for peer review. In this talk, we will discuss the student and instructor experiences in courses offered to three distinct audiences in different venues: (1) a Massively Open On-line Course (MOOC) for off-campus participants, (2) a flipped/blended course for on-campus students, and, most recently, (3) a fully-online course for off-campus students.

  6. On-line structure-lossless digital mammogram image compression

    Science.gov (United States)

    Wang, Jun; Huang, H. K.

    1996-04-01

    This paper proposes a novel on-line structure lossless compression method for digital mammograms during the film digitization process. The structure-lossless compression segments the breast and the background, compresses the former with a predictive lossless coding method and discards the latter. This compression scheme is carried out during the film digitization process and no additional time is required for the compression. Digital mammograms are compressed on-the-fly while they are created. During digitization, lines of scanned data are first acquired into a small temporary buffer in the scanner, then they are transferred to a large image buffer in an acquisition computer which is connected to the scanner. The compression process, running concurrently with the digitization process in the acquisition computer, constantly checks the image buffer and compresses any newly arrived data. Since compression is faster than digitization, data compression is completed as soon as digitization is finished. On-line compression during digitization does not increase overall digitizing time. Additionally, it reduces the mammogram image size by a factor of 3 to 9 with no loss of information. This algorithm has been implemented in a film digitizer. Statistics were obtained based on digitizing 46 mammograms at four sampling distances from 50 to 200 microns.

  7. On-line estimation of concentration parameters in fermentation processes

    Institute of Scientific and Technical Information of China (English)

    XIONG Zhi-hua; HUANG Guo-hong; SHAO Hui-he

    2005-01-01

    It has long been thought that bioprocess, with their inherent measurement difficulties and complex dynamics, posed almost insurmountable problems to engineers. A novel software sensor is proposed to make more effective use of those measurements that are already available, which enable improvement in fermentation process control. The proposed method is based on mixtures of Gaussian processes (GP) with expectation maximization (EM) algorithm employed for parameter estimation of mixture of models. The mixture model can alleviate computational complexity of GP and also accord with changes of operating condition in fermentation processes, i.e., it would certainly be able to examine what types of process-knowledge would be most relevant for local models' specific operating points of the process and then combine them into a global one. Demonstrated by on-line estimate of yeast concentration in fermentation industry as an example, it is shown that soft sensor based state estimation is a powerful technique for both enhancing automatic control performance of biological systems and implementing on-line monitoring and optimization.

  8. Precise On-line Position Measurement for Particle Therapy

    CERN Document Server

    Actis, O; König, S

    2014-01-01

    An on-line beam position monitoring and regular beam stability tests are of utmost importance for the Quality Assurance (QA) of the patient treatment at any particle therapy facility. The Gantry${0.5 mm}2$ at the Paul Scherrer Institute uses a strip ionization chamber for the on-line beam position verification. The design of the strip chamber placed in the beam in front of the patient allows for a small beam penumbra in order to achieve a high-quality lateral beam delivery. The detector granularity and the low noise allow the reconstruction of the signals offered by Gantry${0.5 mm}2$ with a precision of about 0.1 mm. The frond-end electronics and the whole data processing sequence have been optimized for minimizing the dead time between the beam applications to about 2 ms: the charge collection is performed in about 1 ms, read-out takes place in 100 $\\mu$s while data verification and logging are completed in less than 1 ms. The sub-millimeter precision of the lateral reconstruction allows the dose inhomogenei...

  9. Research of on-line detection system for power capacitor

    Science.gov (United States)

    Yao, Junda; Qian, Zheng; Yu, Hao; Xia, Jiuyun

    2016-01-01

    The hidden danger exists in the power capacitor of power system due to long-time operation under the environment of high voltage. Thus, it is possible to induce serious fault, and the on-line detection system is urgently required. In this paper, two methods of the on-line detection system are compared in order to realize the better real-time condition detection. The first method is based on the STM microprocessor with an internal 12 bit A/D converter, which converts analog signals which is arrived from the sample circuit into digital signals, and then the FFT algorithm is used to accomplish the measurement of the voltage and current values of the capacitor. The second method is based on the special electric energy metering IC, which can obtain RMS (Root Mean Square) of voltage and current by processing the sampled data of the voltage and current, and store RMS of voltage and current in its certain registers. The operating condition of the capacitor can be obtained after getting the values of voltage and current. By comparing the measuring results of two methods, the second method could achieve a higher measurement accuracy and more simple construction.

  10. On-line documentation of patient care orders.

    Science.gov (United States)

    Prophet, C M

    1995-01-01

    The INFORMM NIS (Information Network For Online Retrieval & Medical Management Nursing Information System) provides on-line documentation of patient care orders. These orders, generated by the nurse or the physician, prescribe direct patient care and do not include interdepartmental orders such as laboratory, radiology, or pharmacy. The order charting functions support charting efficiency by defaulting previous responses so that the user enters only updates to earlier findings or new data. Available in tables maintained by NIS staff, charting responses provide decision support by suggesting valid results for each order. Using point-of-care devices, nursing staff chart patient data that are immediately available for review by all authorized members of the health care team. These data are printed automatically on computer-generated chart forms every twenty-four hours, but may be printed also on demand. Additionally, the patient data report, containing patient data entered on-line in the sixteen or twenty-four hours immediately preceding the print request, provides a summary that is useful for nurses' report and physicians' rounds.

  11. Short-chain fluorescent tryptophan tags for on-line detection of functional recombinant proteins

    Directory of Open Access Journals (Sweden)

    Siepert Eva-Maria

    2012-09-01

    Full Text Available Abstract Background Conventional fluorescent proteins, such as GFP, its derivatives and flavin mononucleotide based fluorescent proteins (FbFPs are often used as fusion tags for detecting recombinant proteins during cultivation. These reporter tags are state-of-the-art; however, they have some drawbacks, which can make on-line monitoring challenging. It is discussed in the literature that the large molecular size of proteins of the GFP family may stress the host cell metabolism during production. In addition, fluorophore formation of GFP derivatives is oxygen-dependent resulting in a lag-time between expression and fluorescence detection and the maturation of the protein is suppressed under oxygen-limited conditions. On the contrary, FbFPs are also applicable in an oxygen-limited or even anaerobic environment but are still quite large (58% of the size of GFP. Results As an alternative to common fluorescent tags we developed five novel tags based on clustered tryptophan residues, called W-tags. They are only 5-11% of the size of GFP. Based on the property of tryptophan to fluoresce in absence of oxygen it is reasonable to assume that the functionality of our W-tags is also given under anaerobic conditions. We fused these W-tags to a recombinant protein model, the anti-CD30 receptor single-chain fragment variable antibody (scFv Ki-4(scFv and the anti-MucI single-chain fragment variable M12(scFv. During cultivation in Microtiter plates, the overall tryptophan fluorescence intensity of all cultures was measured on-line for monitoring product formation via the different W-tags. After correlation of the scattered light signal representing biomass concentration and tryptophan fluorescence for the uninduced cultures, the fluorescence originating from the biomass was subtracted from the overall tryptophan signal. The resulting signal, thus, represents the product fluorescence of the tagged and untagged antibody fragments. The product fluorescence signal

  12. FEDIX on-line information service: Design, develop, test, and implement, an on-line research and education information service

    Energy Technology Data Exchange (ETDEWEB)

    Rodman, J.A.

    1992-01-01

    The FEDIX Annual Status Report provides details regarding an on-line information project designed, developed and implemented by Federal Information Exchange, Inc., a diversified information services company. This document details the project design activities, summarizes the developmental phases of the project and describes the implementation activities generated to fulfill the project's objectives. The information contained in this document illustrates FIE's continuing commitment to serve as the link that facilitates the dissemination of federal information to the education community. This report reviews the project accomplishments and describes intended service enhancements.

  13. Lower hybrid current drive favoured by electron cyclotron radiofrequency heating

    Energy Technology Data Exchange (ETDEWEB)

    Cesario, R.; Cardinali, A.; Castaldo, C.; Marinucci, M.; Tuccillo, A. A. [Associazione EURATOM/ENEA sulla Fusione, Centro Ricerche Frascati, 00044, Frascati (Italy); Amicucci, L.; Galli, A. [Università di Roma Sapienza, Dipartimento Ingegneria Elettronica, Rome (Italy); Giruzzi, G. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Napoli, F.; Schettini, G. [Università di Roma Tre, Dipartimento Ingegneria Elettronica, Rome (Italy)

    2014-02-12

    The important goal of adding to the bootstrap a fraction of non-inductive plasma current, which would be controlled for obtaining and optimizing steady-state profiles, can be reached by using the Current Drive produced by Lower Hybrid waves (LHCD). FTU (Frascati Tokamak Upgrade) experiments demonstrated, indeed, that LHCD is effective at reactor-graded high plasma density, and the LH spectral broadening is reduced, operating with higher electron temperature in the outer region of plasma column (T{sub e-periphery}). This method was obtained following the guidelines of theoretical predictions indicating that the broadening of launched spectrum produced by parametric instability (PI) should be reduced, and the LHCD effect at high density consequently enabled, under higher (T{sub e-periphery}). In FTU, the temperature increase in the outer plasma region was obtained by operating with reduced particle recycling, lithized walls and deep gas fuelling by means of fast pellet. Heating plasma periphery with electron cyclotron resonant waves (ECRH) will provide a further tool for achieving steady-state operations. New FTU experimental results are presented here, demonstrating that temperature effect at the plasma periphery, affecting LH penetration, occurs in a range of plasma parameters broader than in previous work. New information is also shown on the modelling assessing frequencies and growth rates of the PI coupled modes responsible of spectral broadening. Finally, we present the design of an experiment scheduled on FTU next campaign, where ECRH power is used to slightly increase the electron temperature in the outer plasma region of a high-density discharge aiming at restoring LHCD. Consequent to model results, by operating with a toroidal magnetic field of 6.3 T, useful for locating the electron cyclotron resonant layer at the periphery of the plasma column (r/a∼0.8, f{sub 0}=144 GHz), an increase of T{sub e} in the outer plasma (from 40 eV to 80 eV at r/a∼0.8) is

  14. Status of the ITER Ion Cyclotron H and CD system

    Energy Technology Data Exchange (ETDEWEB)

    Lamalle, P., E-mail: philippe.lamalle@iter.org [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Beaumont, B.; Kazarian, F.; Gassmann, T. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Agarici, G. [Fusion for Energy, Carrer Josep Pla 2, Torres Diagonal Litoral Edificio B3, 08019 Barcelona (Spain); Ajesh, P. [ITER India, Institute for Plasma Research, Bhat, Gandhinagar 382424, Gujarat (India); Alonzo, T. [Solution F, Allée du Verdon, 13770 Venelles (France); Arambhadiya, B. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Argouarch, A. [CEA Cadarache, IRFM, F-13108 St-Paul-lez-Durance (France); Bamber, R. [EURATOM/CCFE Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Berger-By, G.; Bernard, J.-M.; Brun, C. [CEA Cadarache, IRFM, F-13108 St-Paul-lez-Durance (France); Carpentier, S. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Clairet, F.; Colas, L.; Courtois, X. [CEA Cadarache, IRFM, F-13108 St-Paul-lez-Durance (France); Davis, A. [EURATOM/CCFE Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Dechelle, C.; Doceul, L. [CEA Cadarache, IRFM, F-13108 St-Paul-lez-Durance (France); and others

    2013-10-15

    Highlights: ► We summarize the progress and outstanding issues in the development of the ITER Ion Cyclotron Heating and Current Drive (IC H and CD) system. ► The system is designed to robustly couple 20 MW in quasi-CW operation for a broad range of plasma scenarios, and is upgradeable to up to 40 MW. ► The design is rendered challenging by the wide spectrum of requirements and interface constraints to which it is subject. ► R and D is ongoing to validate key antenna components, and to qualify the radio-frequency (RF) sources and the transmission and matching components. ► Intensive numerical modeling and experimental studies on antenna mock-ups have been conducted to validate and optimize the RF design. -- Abstract: The ongoing design of the ITER Ion Cyclotron Heating and Current Drive system (20 MW, 40–55 MHz) is rendered challenging by the wide spectrum of requirements and interface constraints to which it is subject, several of which are conflicting and/or still in a high state of flux. These requirements include operation over a broad range of plasma scenarios and magnetic fields (which prompts usage of wide-band phased antenna arrays), high radio-frequency (RF) power density at the first wall (and associated operation close to voltage and current limits), resilience to ELM-induced load variations, intense thermal and mechanical loads, long pulse operation, high system availability, efficient nuclear shielding, high density of antenna services, remote-handling ability, tight installation tolerances, and nuclear safety function as tritium confinement barrier. R and D activities are ongoing or in preparation to validate critical antenna components (plasma-facing Faraday screen, RF sliding contacts, RF vacuum windows), as well as to qualify the RF power sources and the transmission and matching components. Intensive numerical modeling and experimental studies on antenna mock-ups have been conducted to validate and optimize the RF design. The paper

  15. Quantitative analysis of relationships between irradiation parameters and the reproducibility of cyclotron-produced (99m)Tc yields.

    Science.gov (United States)

    Tanguay, J; Hou, X; Buckley, K; Schaffer, P; Bénard, F; Ruth, T J; Celler, A

    2015-05-21

    Cyclotron production of (99m)Tc through the (100)Mo(p,2n) (99m)Tc reaction channel is actively being investigated as an alternative to reactor-based (99)Mo generation by nuclear fission of (235)U. An exciting aspect of this approach is that it can be implemented using currently-existing cyclotron infrastructure to supplement, or potentially replace, conventional (99m)Tc production methods that are based on aging and increasingly unreliable nuclear reactors. Successful implementation will require consistent production of large quantities of high-radionuclidic-purity (99m)Tc. However, variations in proton beam currents and the thickness and isotopic composition of enriched (100)Mo targets, in addition to other irradiation parameters, may degrade reproducibility of both radionuclidic purity and absolute (99m)Tc yields. The purpose of this article is to present a method for quantifying relationships between random variations in production parameters, including (100)Mo target thicknesses and proton beam currents, and reproducibility of absolute (99m)Tc yields (defined as the end of bombardment (EOB) (99m)Tc activity). Using the concepts of linear error propagation and the theory of stochastic point processes, we derive a mathematical expression that quantifies the influence of variations in various irradiation parameters on yield reproducibility, quantified in terms of the coefficient of variation of the EOB (99m)Tc activity. The utility of the developed formalism is demonstrated with an example. We show that achieving less than 20% variability in (99m)Tc yields will require highly-reproducible target thicknesses and proton currents. These results are related to the service rate which is defined as the percentage of (99m)Tc production runs that meet the minimum daily requirement of one (or many) nuclear medicine departments. For example, we show that achieving service rates of 84.0%, 97.5% and 99.9% with 20% variations in target thicknesses requires producing on average

  16. Electron cyclotron plasma startup in the GDT experiment

    Science.gov (United States)

    Yakovlev, D. V.; Shalashov, A. G.; Gospodchikov, E. D.; Solomakhin, A. L.; Savkin, V. Ya.; Bagryansky, P. A.

    2017-01-01

    We report on a new plasma startup scenario in the gas dynamic trap (GDT) magnetic mirror device. The primary 5 MW neutral beam injection (NBI) plasma heating system fires into a sufficiently dense plasma target (‘seed plasma’), which is commonly supplied by an arc plasma generator. In the reported experiments, a different approach to seed plasma generation is explored. One of the channels of the electron cyclotron resonance (ECR) heating system is used to ionize the neutral gas and build up the density of plasma to a level suitable for NBI capture. After a short transition of approximately 1 ms the discharge becomes essentially similar to a standard one initiated by the plasma gun. This paper presents the discharge scenario and experimental data on the seed plasma evolution during ECRH, along with the dependencies on incident microwave power, magnetic configuration and pressure of a neutral gas. The characteristics of the consequent high-power NBI discharge are studied and differences from the conventional scenario are discussed. A theoretical model describing the ECR breakdown and the seed plasma accumulation in a large-scale mirror trap is developed on the basis of the GDT experiment.

  17. Cyclotron Production of Radionuclides for Nuclear Medicine at Academic Centers

    Science.gov (United States)

    Lapi, Suzanne

    2016-09-01

    The increase in use of radioisotopes for medical imaging has led to the development of new accelerator targetry and separation techniques for isotope production. For example, the development of longer-lived position emitting radionuclides has been explored to allow for nuclear imaging agents based on peptides, antibodies and nanoparticles. These isotopes (64Cu, 89Zr, 86Y) are typically produced via irradiation of solid targets on smaller cyclotrons (10-25 MeV) at academic or hospital based facilities. Recent research has further expanded the toolbox of PET tracers to include additional isotopes such as 52Mn, 55Co, 76Br and others. The smaller scale of these types of facilities can enable the straightforward involvement of students, thus adding to the next generation of nuclear science leaders. Research pertaining to development of robust and larger scale production technologies including solid target systems and remote systems for transport and purification of these isotopes has enabled both preclinical and clinical imaging research for many diseases. In particular, our group has focused on the use of radiolabeled antibodies for imaging of receptor expression in preclinical models and in a clinical trial of metastatic breast cancer patients.

  18. Applied research with cyclotron beams at FLNR JINR

    Energy Technology Data Exchange (ETDEWEB)

    Oganessian, Yu.Ts.; Apel, P.Yu.; Didyk, A.Yu.; Dmitriev, S.N.; Gulbekian, G.G. [Joint Inst. for Nuclear Research, Dubna, Moscow (Russian Federation). Flerov Lab. of Nuclear Reactions

    1997-03-01

    The Center of Applied Physics at the Flerov Laboratory carries out an R and D program comprising development of track membrane technology, materials research with heavy ion beams and production of radioisotopes. Experiments are performed on three cyclotrons: U-400, U-200 and IC-100 providing a wide variety of ion beams with the energies of 1 to 10 MeV/u. The activity on track membranes (TMs) includes studies of track formation in polymers and latent track structure, track sensitization and etching, methods of membrane testing, development of track membranes on the basis of new materials, surface modification of TMs, design and construction of facilities for track membrane production. Recent experiments on heavy ion-induced radiation damage in non-polymeric substances have been devoted to defect creation in semiconductor and dielectric single crystals. TEM, SEM, STM and `in situ` luminescent spectroscopy are used to investigate heavy ion effects. Methods for producing several isotopes of high radiochemical and isotopic purity for medical, biomedical and environmental protection applications have been developed. (author)

  19. Isotope exchange by Ion Cyclotron Wall Conditioning on JET

    Energy Technology Data Exchange (ETDEWEB)

    Wauters, T., E-mail: t.wauters@fz-juelich.de [Laboratory for Plasma Physics, ERM/KMS, TEC Partner, 1000 Brussels (Belgium); Douai, D.; Kogut, D. [CEA, IRFM, F-13108 St-Paul-Lez-Durance (France); Lyssoivan, A. [Laboratory for Plasma Physics, ERM/KMS, TEC Partner, 1000 Brussels (Belgium); Brezinsek, S. [Forschungszentrum Jülich, Institut für Energie- und Klimaforschung Plasmaphysik, 52425 Jülich (Germany); Belonohy, E. [Max-Planck Institut für Plasmaphysik, 85748 Garching (Germany); Blackman, T. [JET-EFDA, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Bobkov, V. [Max-Planck Institut für Plasmaphysik, 85748 Garching (Germany); Crombé, K. [Laboratory for Plasma Physics, ERM/KMS, TEC Partner, 1000 Brussels (Belgium); Drenik, A. [Jožef Stefan Institute, 1000 Ljubljana (Slovenia); Graham, M. [JET-EFDA, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Joffrin, E. [CEA, IRFM, F-13108 St-Paul-Lez-Durance (France); Lerche, E. [Laboratory for Plasma Physics, ERM/KMS, TEC Partner, 1000 Brussels (Belgium); Loarer, T. [CEA, IRFM, F-13108 St-Paul-Lez-Durance (France); Lomas, P.L.; Mayoral, M.-L.; Monakhov, I. [JET-EFDA, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Oberkofler, M. [Max-Planck Institut für Plasmaphysik, 85748 Garching (Germany); Philipps, V. [Forschungszentrum Jülich, Institut für Energie- und Klimaforschung Plasmaphysik, 52425 Jülich (Germany); Plyusnin, V. [IST, Instituto de Plasmas e Fusão Nuclear, 1049-001 Lisboa (Portugal); and others

    2015-08-15

    The isotopic exchange efficiencies of JET Ion Cyclotron Wall Conditioning (ICWC) discharges produced at ITER half and full field conditions are compared for JET carbon (C) and ITER like wall (ILW). Besides an improved isotope exchange rate on the ILW providing cleaner plasma faster, the main advantage compared to C-wall is a reduction of the ratio of retained discharge gas to removed fuel. Complementing experimental data with discharge modeling shows that long pulses with high (∼240 kW coupled) ICRF power maximizes the wall isotope removal per ICWC pulse. In the pressure range 1–7.5 × 10{sup −3} Pa, this removal reduces with increasing discharge pressure. As most of the wall-released isotopes are evacuated by vacuum pumps in the post discharge phase, duty cycle optimization studies for ICWC on JET-ILW need further consideration. The accessible reservoir by H{sub 2}-ICWC at ITER half field conditions on the JET-ILW preloaded by D{sub 2} tokamak operation is estimated to be 7.3 × 10{sup 22} hydrogenic atoms, and may be exchanged within 400 s of cumulated ICWC discharge time.

  20. Electron-cyclotron plasma startup in the GDT experiment

    CERN Document Server

    Yakovlev, D V; Gospodchikov, E D; Solomakhin, A L; Savkin, V Ya; Bagryansky, P A

    2016-01-01

    The paper reports on a new plasma startup scenario in the Gas Dynamic Trap (GDT) magnetic mirror device. The primary 5 MW neutral beam injection (NBI) plasma heating system fires into a sufficiently dense plasma target ("seed plasma"), which is commonly supplied by an arc plasma generator. In the reported experiments, a different approach to seed plasma generation is explored. One of the channels of the electron cyclotron resonance (ECR) heating system is used to ionize the neutral gas and build up the density of plasma to a level suitable for NBI capture. After a short transition (about 1 ms) the discharge becomes essentially similar to a standard one initiated by the plasma gun. The paper presents the discharge scenario and experimental data on the seed plasma evolution during ECR heating, along with the dependencies on incident microwave power, magnetic configuration and pressure of a neutral gas. The characteristics of consequent high-power NBI discharge are studied and differences to the conventional sce...

  1. ATLAS 10 GHz electron cyclotron resonance ion source upgrade project

    CERN Document Server

    Moehs, D P; Pardo, R C; Xie, D

    2000-01-01

    A major upgrade of the first ATLAS 10 GHz electron cyclotron resonance (ECR) ion source, which began operations in 1987, is in the planning and procurement phase. The new design will convert the old two-stage source into a single-stage source with an electron donor disk and high gradient magnetic field that preserves radial access for solid material feeds and pumping of the plasma chamber. The new magnetic-field profile allows for the possibility of a second ECR zone at a frequency of 14 GHz. An open hexapole configuration, using a high-energy-product Nd-Fe-B magnet material, having an inner diameter of 8.8 cm and pole gaps of 2.4 cm, has been adopted. Models indicate that the field strengths at the chamber wall, 4 cm in radius, will be 9.3 kG along the magnet poles and 5.6 kG along the pole gaps. The individual magnet bars will be housed in austenitic stainless steel, allowing the magnet housing within the aluminum plasma chamber to be used as a water channel for direct cooling of the magnets. Eight solenoid...

  2. Polarization of electron cyclotron emission spectra in LHD

    Energy Technology Data Exchange (ETDEWEB)

    Vries, P.C. de; Nagayama, Y.; Kawahata, K.; Inagaki, S.; Sasao, H. [National Inst. for Fusion Science, Toki, Gifu (Japan); Nagasaki, K.

    1999-07-01

    Electron cyclotron emission (ECE) can be used to determine the electron temperature profile in magnetized plasmas. The complex structure of the magnetic field configuration in the Large Helical Device (LHD), which has a large shear, complicates the analysis of the ECE spectrum. In a sheared magnetic field the propagation of X and O-mode polarization through the plasma are coupled, causing mode conversion and polarization rotation. Mode scrambling is also caused by wall reflections. In this report, this mode conversion in LHD is numerically analyzed. It was found that at low density mode conversion scrambles the ECE spectra. However, at higher density (n{sub eo} > 1.0{center_dot}10{sup 19} m{sup -3}) the polarization mode is found to rotate with the sheared magnetic field, yielding only a negligible mode conversion. Wall reflections are found to depolarize the ECE spectrum. Notwithstanding the LHD magnetic configuration, it is shown that temperature profiles could be revealed from the ECE spectra. (author)

  3. Fourier transform ion cyclotron resonance mass spectrometry: a primer.

    Science.gov (United States)

    Marshall, A G; Hendrickson, C L; Jackson, G S

    1998-01-01

    This review offers an introduction to the principles and generic applications of FT-ICR mass spectrometry, directed to readers with no prior experience with the technique. We are able to explain the fundamental FT-ICR phenomena from a simplified theoretical treatment of ion behavior in idealized magnetic and electric fields. The effects of trapping voltage, trap size and shape, and other nonidealities are manifested mainly as perturbations that preserve the idealized ion behavior modified by appropriate numerical correction factors. Topics include: effect of ion mass, charge, magnetic field, and trapping voltage on ion cyclotron frequency; excitation and detection of ICR signals; mass calibration; mass resolving power and mass accuracy; upper mass limit(s); dynamic range; detection limit, strategies for mass and energy selection for MSn; ion axialization, cooling, and remeasurement; and means for guiding externally formed ions into the ion trap. The relation of FT-ICR MS to other types of Fourier transform spectroscopy and to the Paul (quadrupole) ion trap is described. The article concludes with selected applications, an appendix listing accurate fundamental constants needed for ultrahigh-precision analysis, and an annotated list of selected reviews and primary source publications that describe in further detail various FT-ICR MS techniques and applications.

  4. ATLAS 10 GHz electron cyclotron resonance ion source upgrade project

    Energy Technology Data Exchange (ETDEWEB)

    Moehs, D. P. [Argonne National Laboratory, Physics Division, Argonne, Illinois 60439 (United States); Vondrasek, R. [Argonne National Laboratory, Physics Division, Argonne, Illinois 60439 (United States); Pardo, R. C. [Argonne National Laboratory, Physics Division, Argonne, Illinois 60439 (United States); Xie, D. [Berkeley Ion Equipment Inc., Santa Clara, California 95054 (United States)

    2000-02-01

    A major upgrade of the first ATLAS 10 GHz electron cyclotron resonance (ECR) ion source, which began operations in 1987, is in the planning and procurement phase. The new design will convert the old two-stage source into a single-stage source with an electron donor disk and high gradient magnetic field that preserves radial access for solid material feeds and pumping of the plasma chamber. The new magnetic-field profile allows for the possibility of a second ECR zone at a frequency of 14 GHz. An open hexapole configuration, using a high-energy-product Nd-Fe-B magnet material, having an inner diameter of 8.8 cm and pole gaps of 2.4 cm, has been adopted. Models indicate that the field strengths at the chamber wall, 4 cm in radius, will be 9.3 kG along the magnet poles and 5.6 kG along the pole gaps. The individual magnet bars will be housed in austenitic stainless steel, allowing the magnet housing within the aluminum plasma chamber to be used as a water channel for direct cooling of the magnets. Eight solenoid coils from the existing ECR will be enclosed in an iron yoke to produce the axial mirror. Based on a current of 500 A, the final model predicts a minimum B field of 3 kG with injection and extraction mirror ratios of 4.4 and 2.9, respectively. (c) 2000 American Institute of Physics.

  5. A Michelson Interferometer for Electron Cyclotron Emission Measurements on EAST

    Science.gov (United States)

    Liu, Yong; Stefan, Schmuck; Zhao, Hailin; John, Fessey; Paul, Trimble; Liu, Xiang; Zhu, Zeying; Zang, Qing; Hu, Liqun

    2016-12-01

    A Michelson interferometer, on loan from EFDA-JET (Culham, United Kingdom) has recently been commissioned on the experimental advanced superconducting tokamak (EAST, ASIPP, Hefei, China). Following a successful in-situ absolute calibration the instrument is able to measure the electron cyclotron emission (ECE) spectrum, from 80 GHz to 350 GHz in extraordinary mode (X-mode) polarization, with high accuracy. This allows the independent determination of the electron temperature profile from observation of the second harmonic ECE and the possible identification of non-Maxwellian features by comparing higher harmonic emission with numerical simulations. The in-situ calibration results are presented together with the initial measured temperature profiles. These measurements are then discussed and compared with other independent temperature profile measurements. This paper also describes the main hardware features of the diagnostic and the associated commissioning test results. supported by National Natural Science Foundation of China (Nos. 11405211, 11275233), and the National Magnetic Confinement Fusion Science Program of China (Nos. 2013GB106002, 2015GB101000), and the RCUK Energy Programme (No. EP/I501045), partly supported by the JSPS-NRF-NSFC A3 Foresight Program in the Field of Plasma Physics (NSFC: No. 11261140328)

  6. Maryland University sectored isochronous cyclotron (MUSIC): Progress report No. 14

    Energy Technology Data Exchange (ETDEWEB)

    1967-01-10

    The past quarter has seen further progress in the solution of the problem of achieving a cyclotron which meets or exceeds the performance requirements. The magnet system, with the exception of the trim coils and their supplies, is all on order or about to be ordered, and a high confidence level exists that the system will meet all requirements. The rf system studies, nearly complete, have indicated that the solution chosen will meet the frequency requirements and will be within the power expected. The center studies, complete in the first phase, have resulted in a preliminary center design of the electrostatic focusing system and a design of the magnetic center which provides the required axial focusing. A high degree of cooperation on the center study programs between the U of M and CSF has efficiently yielded these results. The overall schedule continues to be maintained, and the program is expected to be completed on the 37-month schedule. For better control and greater visibility on schedule progress, two reference points have been selected as more immediate objectives. These are 17 July 1967 for the start of the magnet testing program and 2 October 1967 as the start of the rf high power tests. Each task involved is being analyzed with these dates in mind, and they appear to be reasonable.

  7. Electron cyclotron resonance heating in a short cylindrical plasma system

    Indian Academy of Sciences (India)

    Vipin K Yadav; D Bora

    2004-09-01

    Electron cyclotron resonance (ECR) plasma is produced and studied in a small cylindrical system. Microwave power is delivered by a CW magnetron at 2.45 GHz in TE10 mode and launched radially to have extraordinary (X) wave in plasma. The axial magnetic field required for ECR in the system is such that the first two ECR surfaces ( = 875.0 G and = 437.5 G) reside in the system. ECR plasma is produced with hydrogen with typical plasma density e as 3.2 × 1010 cm-3 and plasma temperature e between 9 and 15 eV. Various cut-off and resonance positions are identified in the plasma system. ECR heating (ECRH) of the plasma is observed experimentally. This heating is because of the mode conversion of X-wave to electron Bernstein wave (EBW) at the upper hybrid resonance (UHR) layer. The power mode conversion efficiency is estimated to be 0.85 for this system. The experimental results are presented in this paper.

  8. A Fingerprint Minutiae Matching Method Based on Line Segment Vector

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Minutiae-based fingerprint matching is the most commonly used in an automatic fingerprint identification system. In this paper, we propose a minutia matching method based on line segment vector. This method uses all the detected minutiae (the ridge ending and the ridge bifurcation) in a fingerprint image to create a set of new vectors (line segment vector). Using these vectors, we can determine a truer reference point more efficiently. In addition, this new minutiae vector can also increase the accuracy of the minutiae matching. By experiment on the public domain collections of fingerprint images fvc2004 DB3 set A and DB4 set A, the result shows that our algorithm can obtain an improved verification performance.

  9. BCal: an on-line Bayesian radiocarbon calibration tool

    Directory of Open Access Journals (Sweden)

    Caitlin E. Buck

    1999-09-01

    Full Text Available In this paper we describe newly launched software for on-line Bayesian calibration of archaeological radiocarbon determinations. The software is known as BCal and we invite members of the world-wide archaeological research community to use it should they so wish. All that is required to gain access to the software is a computer connected to the Internet with a modern World-wide Web browser (of the sort you are probably using to read this. BCal does not require access to any additional 'Plug-ins' on your machine. Since the computations needed to obtain the calibrations are undertaken on the BCal server, if you have enough computer power to run your World-wide Web browser you have enough power to use BCal.

  10. On-line blind separation of non-stationary signals

    Directory of Open Access Journals (Sweden)

    Todorović-Zarkula Slavica

    2005-01-01

    Full Text Available This paper addresses the problem of blind separation of non-stationary signals. We introduce an on-line separating algorithm for estimation of independent source signals using the assumption of non-stationary of sources. As a separating model, we apply a self-organizing neural network with lateral connections, and define a contrast function based on correlation of the network outputs. A separating algorithm for adaptation of the network weights is derived using the state-space model of the network dynamics, and the extended Kalman filter. Simulation results obtained in blind separation of artificial and real-world signals from their artificial mixtures have shown that separating algorithm based on the extended Kalman filter outperforms stochastic gradient based algorithm both in convergence speed and estimation accuracy.

  11. On-Line Adaptive Radiation Therapy: Feasibility and Clinical Study

    Directory of Open Access Journals (Sweden)

    Taoran Li

    2010-01-01

    Full Text Available The purpose of this paper is to evaluate the feasibility and clinical dosimetric benefit of an on-line, that is, with the patient in the treatment position, Adaptive Radiation Therapy (ART system for prostate cancer treatment based on daily cone-beam CT imaging and fast volumetric reoptimization of treatment plans. A fast intensity-modulated radiotherapy (IMRT plan reoptimization algorithm is implemented and evaluated with clinical cases. The quality of these adapted plans is compared to the corresponding new plans generated by an experienced planner using a commercial treatment planning system and also evaluated by an in-house developed tool estimating achievable dose-volume histograms (DVHs based on a database of existing treatment plans. In addition, a clinical implementation scheme for ART is designed and evaluated using clinical cases for its dosimetric qualities and efficiency.

  12. On-line methods for rotorcraft aeroelastic mode identification

    Science.gov (United States)

    Molusis, J. A.; Kleinman, D. L.

    1982-01-01

    The requirements for the on-line identification of rotorcraft aeroelastic blade modes from random response test data are presented. A recursive maximum likelihood (RML) technique is used in conjunction with a bandpass filter to identify isolated blade mode damping and frequency. The RML technique is demonstrated to have excellent convergence characteristics in random measurement noise and random process noise excitation. The RML identification technique uses an ARMA representation for the aeroelastic stochastic system and requires virtually no user interaction while providing accurate confidence bands on the parameter estimates. Comparisons are made with an off-line Newton type maximum likelihood algorithm which uses a state variable model representation. Results are presented from simulation random response data which quantify the identifed parameter convergence behavior for various levels of random excitation which is typical of wind tunnel turbulence levels. The RML technique is applied to hingless rotor test data from the NASA Langley Research Center Helicopter Hover Facility.

  13. 3rd Computer Science On-line Conference

    CERN Document Server

    Senkerik, Roman; Oplatkova, Zuzana; Silhavy, Petr; Prokopova, Zdenka

    2014-01-01

    This book is based on the research papers presented in the 3rd Computer Science On-line Conference 2014 (CSOC 2014).   The conference is intended to provide an international forum for discussions on the latest high-quality research results in all areas related to Computer Science. The topics addressed are the theoretical aspects and applications of Artificial Intelligences, Computer Science, Informatics and Software Engineering.   The authors provide new approaches and methods to real-world problems, and in particular, exploratory research that describes novel approaches in their field. Particular emphasis is laid on modern trends in selected fields of interest. New algorithms or methods in a variety of fields are also presented.   This book is divided into three sections and covers topics including Artificial Intelligence, Computer Science and Software Engineering. Each section consists of new theoretical contributions and applications which can be used for the further development of knowledge of everybod...

  14. On-line control of the nonlinear dynamics for synchrotrons

    Science.gov (United States)

    Bengtsson, J.; Martin, I. P. S.; Rowland, J. H.; Bartolini, R.

    2015-07-01

    We propose a simple approach to the on-line control of the nonlinear dynamics in storage rings, based on compensation of the nonlinear resonance driving terms using beam losses as the main indicator of the strength of a resonance. The correction scheme is built on the analysis of the resonance driving terms in first perturbative order and on the possibility of using independent power supplies in the sextupole magnets, which is nowadays present in many synchrotron light sources. Such freedom allows the definition of "smart sextupole knobs" attacking each resonance separately. The compensation scheme has been tested at the Diamond light source and proved to be effective in opening up the betatron tune space, resonance free, available to the electron beam and to improve the beam lifetime.

  15. On-line Test for Train Communication Based System

    Institute of Scientific and Technical Information of China (English)

    Zeng Xiaoqing; Masayuki Matsumoto; Kinji Mori; XU Fucang

    2002-01-01

    This paper gives out a new train automatic control system, which is based on train communication, and proposes a high assurance method to construct the system from current system. In current automatic train control (ATC) system, the central logic device detects position of each train and calculates permissible speed of each blocking section. Therefore, the central logic device controls speed of all trains. On the contrary, in the new system proposed in this paper, there is no central logical device and, train can communicate each other. The train detects the position and calculates the permissible speed itself according to the received position information of the preceding train. In the traditional method of changing an old system to a new one, test must be done off-line.While the integration technique proposed in this paper achieves on-line properties, and high assurance can be satisfied.

  16. The Monitor System for the LHCb on-line farm

    CERN Document Server

    Bonifazi, F; Carbone, A; Galli, D; Gregori, D; Marconi, U; Peco, G; Vagnoni, V

    2005-01-01

    The aim of the LHCb on-line farm Monitor System is to keep under control all the working indicators which are relevant for the farm operation, and to set the appropriate alarms whenever an error or a critical condition comes up. Since the most stressing tasks of the farm are the data transfer and processing, relevant indicators includes the CPU and the memory load of the system, the network interface and the TCP/IP stack parameters, the rates of the interrupts raised by the network interface card and the detailed status of the running processes. The monitoring of computers’ physical conditions (temperatures, fan speeds and motherboard voltages) are the subject of a separate technical note, since they are accessed in a different way, by using the IPMI protocol.

  17. The Message Logger for the LHCb on-line farm

    CERN Document Server

    Bonifazi, F; Carbone, A; Galli, D; Gregori, D; Marconi, U; Peco, G; Vagnoni, V

    2005-01-01

    The Message Logger is a utility which provide a logger facility for the processes running on the nodes of the on-line farm. It can also be used to collect the processes stdout/stderr. The Message Logger can be exploited using two different policies: either as a no-drop logger facility (messages cannot be lost, but a write to the logger facility blocks in case of full-buffer condition, due e.g. to a network congestion) or as a congestion-proof logger facility (a write to the logger facility never locks even in case of network congestion, but, in this case, messages are dropped). The Message Logger package includes a Linux DIM server (logSrv), a Linux terminal/command-line DIM client (logViewer) and a PVSS DIM client.

  18. The Task Manager for the LHCb On-Line Farm

    CERN Document Server

    Bonifazi, F; Carbone, A; Galli, D; Gregori, D; Marconi, U; Peco, G; Vagnoni, V

    2004-01-01

    The Task Manager is a utility to start, stop and list processes on the on-line farm. Each process started by the Task Manager has a string environment variable set, named UTGID (User defined unique Thread Group Identifier) which allows to identify the process. The Task Manager uses the UTGID to list the running processes and to identify the processes to be stopped. It has also the ability to start a process using a particular user name and to set the scheduler type and the priority for the process itself. The Task Manager package includes a Linux DIM server (tmSrv), four Linux command line DIM clients (tmStart, tmLs, tmKill and tmStop) and a JCOP (Joint Control Project) PVSS client.

  19. On-line corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Richter, Sonja; Thorarinsdottir, R.I.; Hilbert, Lisbeth Rischel

    2004-01-01

    Traditionally corrosion monitoring in district heating systems has been performed offline via weight loss coupons. These measurements give information about the past and not the present situation and require long exposure time (weeks or months). The good quality of district heating medium makes...... corrosion monitoring a challenge. Under normal conditions the pH is high (app. 9), conductivity is low (app. 10-200 µS/cm) and the concentration of dissolved oxygen is negligible. The low corrosion rates (in the order of µm/y) are difficult to measure and furthermore, factors such as hydrogen sulphide......), Electrochemical Noise (EN) and Zero Resistance Ammetry (ZRA). Electrochemical Resistance (ER) has also been used to measure corrosion. The method traditionally only measures corrosion off-line but with newly developed high-sensitive ER technique developed by MetriCorr in Denmark, on-line monitoring is possible...

  20. Review of Worcestershire On-line Fabric Type Series website

    Directory of Open Access Journals (Sweden)

    Beverley Nenk

    2003-06-01

    Full Text Available The study of archaeological ceramics is advanced through the creation and development of regional and national pottery type-series, which contain samples of each type of pottery identified from a particular area or region. Pottery researchers working in any period, from prehistoric to post-medieval, require access to such type-series, and to their associated data, in order to be able to advance the identification of all types of pottery, not only those types produced in the local area, but those produced in surrounding regions, as well as those imported from abroad. The publication of such type-series, as well as their accessibility to researchers, is essential if the information they contain is to be disseminated. The development of the Worcestershire On-Line Fabric Type Series is the first stage in a remarkable project designed to make the complete fabric and form type series for Worcestershire ceramics accessible on the internet. As part of the Historic Environment Record for Worcestershire, formerly the Sites and Monuments Record, it is designed to improve access to finds and environmental data, with the aim of encouraging and facilitating research. Funded by Worcestershire County Council as part of its commitment to e-government, it is being developed by Worcestershire County Council Archaeology Service with OxfordArchDigital. It is one of a proposed series of on-line specialist resources (to include, for example, clay pipes, environmental archaeology, flint tools, historic buildings, which are also designed to stand alone as research tools. The ceramics website is the first part of Pottery in Perspective, a web-based project to provide information on the pottery used and made in Worcestershire from prehistory to c. 1900AD.

  1. A revolutionary concept to improve the efficiency of ion cyclotron antennas

    Science.gov (United States)

    Milanesio, D.; Maggiora, R.

    2014-06-01

    The successful design of an ion cyclotron (IC) antenna mainly relies on the capability of coupling high power to the plasma (MW), feature that is currently reached by allowing rather high voltages (tens of kV) on the unavoidable unmatched part of the feeding lines. This requirement is often responsible of arcs along the transmission lines and other unwanted phenomena, such as rectification discharges or hotspots, that considerably limit the usage of IC launchers. In this work, we suggest and describe a revolutionary approach based on high impedance surfaces, which allows to increase the antenna radiation efficiency and, hence, to highly reduce the imposed voltages to couple the same level of power to the plasma. High-impedance surfaces are periodic metallic structures (patches) displaced usually on top of a dielectric substrate and grounded by means of vertical posts usually embedded inside a dielectric, in a mushroom-like shape. In terms of working properties, high impedance surfaces are electrically thin in-phase reflectors, i.e., they present a high impedance, within a given frequency band, such that the image currents are in-phase with the currents of the antenna itself, thus determining a significant efficiency increase. While the usual design of a high impedance surface requires the presence of a dielectric layer, some alternative solutions can be realised in vacuum, taking advantage of double layers of metallic patches. After an introductory part on the properties of high impedance surfaces, this work documents both their design by means of numerical codes and their implementation on a scaled mock-up.

  2. Evaluation of Mo99 and Tc99m Productions Based on a High-Performance Cyclotron

    Directory of Open Access Journals (Sweden)

    J. Esposito

    2013-01-01

    Full Text Available Following preliminary feasibility studies which started at Legnaro National Laboratories (LNL in 2011, the Italian National Institute for Nuclear Physics (INFN research activities are underway aiming at the alternative, accelerator-driven, Mo99/Tc99m production routes. One of the most promising approaches is to use 100Mo-enriched (i.e., >99% molybdenum metallic targets, bombarded with high-beam-current, high-energy proton cyclotrons. In order to get a comprehensive map of radionuclides expected, a detailed theoretical investigation has been carried out using the TALYS-TENDL 2012 excitation functions extended up to (p,6n, (p,p5n, and (p,2p4n levels. A series of quality parameters have thus been calculated both at the end of beam (EOB and at longer times. Results point out that accelerator-99Mo is of limited interest for a possible massive production because of the quite low specific activity with respect to reactor-99Mo. Accelerator-Tc99m quality parameters (i.e., radionuclidic purity (RNP, isotopic purity (IP, and specific activities calculated are instead quite close to the generator-Tc. Calculations at 15, 20, and 25 MeV have thus been performed to assess the best operative irradiation condition for Tc99m production while minimizing both the short-lived and long-lived Tc contaminant radionuclides. Although present in minimum quantities, Tc contaminants may indeed have an impact either on the pharmaceutical labeling procedures or on contributing to patient radiation dose during the diagnostic procedures.

  3. A revolutionary concept to improve the efficiency of ion cyclotron antennas

    Energy Technology Data Exchange (ETDEWEB)

    Milanesio, D., E-mail: daniele.milanesio@polito.it; Maggiora, R., E-mail: riccardo.maggiora@polito.it [Politecnico di Torino, Dipartimento di Elettronica e Telecomunicazioni (DET), Torino (Italy)

    2014-06-15

    The successful design of an ion cyclotron (IC) antenna mainly relies on the capability of coupling high power to the plasma (MW), feature that is currently reached by allowing rather high voltages (tens of kV) on the unavoidable unmatched part of the feeding lines. This requirement is often responsible of arcs along the transmission lines and other unwanted phenomena, such as rectification discharges or hotspots, that considerably limit the usage of IC launchers. In this work, we suggest and describe a revolutionary approach based on high impedance surfaces, which allows to increase the antenna radiation efficiency and, hence, to highly reduce the imposed voltages to couple the same level of power to the plasma. High-impedance surfaces are periodic metallic structures (patches) displaced usually on top of a dielectric substrate and grounded by means of vertical posts usually embedded inside a dielectric, in a mushroom-like shape. In terms of working properties, high impedance surfaces are electrically thin in-phase reflectors, i.e., they present a high impedance, within a given frequency band, such that the image currents are in-phase with the currents of the antenna itself, thus determining a significant efficiency increase. While the usual design of a high impedance surface requires the presence of a dielectric layer, some alternative solutions can be realised in vacuum, taking advantage of double layers of metallic patches. After an introductory part on the properties of high impedance surfaces, this work documents both their design by means of numerical codes and their implementation on a scaled mock-up.

  4. Determination of anions with an on-line capillary electrophoresis method; Anionien on-line maeaeritys kapillaarielektroforeesilla - MPKT 10

    Energy Technology Data Exchange (ETDEWEB)

    Siren, H.; Saerme, T.; Kotiaho, T.; Hiissa, T.; Savolahti, P.; Komppa, V. [VTT Chemical Technology, Espoo (Finland)

    1998-12-31

    The aim of the study was to set-up an on-line capillary electrophoresis method for determination of anions in process waters of pulp and paper industry with exporting the results to the process control system of the mill. The quantification is important, since it will give information about the possible causes of precipitation. In recent years, the capillary electrophoresis (CE) due to its high separation efficiency has been shown as a method to take into consideration when analyzing chemical species ranging from small inorganic anions to different macromolecules. Many compounds are not easily detected in their native state, why analysis methods must be developed to improve their detection. Especially, small inorganic and organic anions which do not have chromophores are not sensitive enough for direct-UV detection. In such analyses the anions are mostly detected with indirect-UV technique. Capillary electrophoresis instruments are used to analyze samples in off-line, which seldom represent the situation in process. Therefore, on-line instrument technology with autoanalyzing settings will be needed in quality control. The development of a fully automatic capillary electrophoresis system is underway in co-operation with KCL (The Finnish Pulp and Paper Research Institute). In our research, we have first concentrated on the determination of sulphate in waters of paper industry. The method used for detection of sulphate is based on indirect-UV detection with CE, where the background electrolyte (BGE) is an absorbing mixture of secondary amines. The whole procedure for quantification of sulphate is performed within 15 minutes, after which a new sample is analyzed automatically. The only sample pretreatment is filtration, which is necessary before analysis. The concentrations of sulphate in process waters tested were between 300 and 800 ppm. Our tests show that a simultaneous determination of chloride, sulphate, nitrate, nitrite, sulphite, carbonate and oxalate is also

  5. Alternative Energies

    Energy Technology Data Exchange (ETDEWEB)

    Planting, A.; De saint Jacob, Y.; Verwijs, H.; Belin, H.; Preesman, L.

    2009-03-15

    In two articles, one interview and one column attention is paid to alternative energies. The article 'A new light on saving energy' discusses the option to save energy by modernising lighting systems in urban areas. The column 'View from Paris' focuses on investment decisions in France with regard to renewable energy and energy savings. The article 'Europe turns a blind eye to big battery' discusses developments in batteries to store energy. The interview concerns fuel cell expert and formerly President of UTC Power Jan van Dokkum. The last article gives a brief overview of the European Energy Research Alliance (EERA) and the challenges this alliance will have to face with regard to climate change and energy security.

  6. [Hemodiafiltration with on-line production of bicarbonate infusate: 5 years of clinical experience].

    Science.gov (United States)

    Canaud, B; N'Guyen, Q V; Bouloux-Polito, C; Stec, F; Mion, C

    1992-01-01

    Despite its potential advantages HDF has not gained large clinical acceptance among nephrologist due to its technical complexity and to the large quantity of pharmaceutical substitution fluid needed. HDF with on-line production of substitution fluid from dialysate simplifies the procedure and reduces the cost of treatment session. We treated regularly 13 high risk and/or non-compliant patients (9 males, 4 females) with HDF for 46 +/- 17 months. HDF program consisted of 3 sessions weekly lasting 210 +/- 10 mn with blood flow rate 350 +/- 20 ml/mn and fluid volume exchange of 20 liters/session. High flux dialyzers (HF80, Filtral 16) were reused 6 to 13 times automatically on a Renatron machine with peroxyacetic acid solution as sole cleaning and disinfecting agent. Microbiologic quality of infusate was assessed by membrane filtration culturing method and LAL endotoxin determination. 3937 HDF sessions were performed. 57.140 I of substitution fluid were infused IV to patients. Eight pyrogenic reactions were observed: 2 due to septicemia related to catheter infection and 6 from unknown origin. Adequacy of program was achieved in all patients. Blood pressure control was satisfactorily obtained without antihypertensive medication in 12/13 patients. Effective weekly integrated urea clearances was 150 +/- 15 l/wk, KT/V index was 1.50 +/- 0.10, urea TAC 20 +/- 2 mM/l and protein catabolic rate 1.40 +/- 0.10 g/kg/24 h. We conclude that HDF with on-line production of bicarbonate substitution fluid is a safe and highly efficient method cost-competitive with bicarbonate HD, which offers an interesting alternative for renal replacement therapy.

  7. Women Physicians Are Early Adopters of On-Line Continuing Medical Education

    Science.gov (United States)

    Harris, John M., Jr.; Novalis-Marine, Cheryl; Harris, Robin B.

    2003-01-01

    Introduction: On-line continuing medical education (CME) provides advantages to physicians and to medical educators. Although practicing physicians increasingly use on-line CME to meet their educational needs, the overall use of on-line CME remains limited. There are few data to describe the physicians who use this new educational medium; yet,…

  8. 77 FR 55811 - Manufacturing Extension Partnership Advisory Board On-line Open Meeting

    Science.gov (United States)

    2012-09-11

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board On-line... Manufacturing Extension Partnership (MEP) Advisory Board will hold an open, on-line meeting via webcast on... their remote location. Questions regarding the on-line meeting should be sent to the...

  9. Electron-cyclotron heating in the Constance 2 mirror experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mauel, Michael E.

    1982-09-01

    Electron cyclotron heating of a highly-ionized plasma in mirror geometry is investigated. The experimental diagnosis of the electron energy distribution and the comparison of the results of this diagnosis with a two dimensional, time-dependent Fokker-Planck simulation are accomplished in four steps. (1) First, the power balance of the heated and unheated Constance 2 plasma is analyzed experimentally. It is concluded that the heated electrons escape the mirror at a rate dominated by a combination of the influx of cool electrons from outside the mirror and the increased loss rate of the ions. (2) The microwave parameters at the resonance zones are then calculated by cold-plasma ray tracing. High N/sub parallel/ waves are launched and for these waves, strong first-pass absorption is predicted. The absorption strength is qualitatively checked in the experiment by surrounding the plasma with non-reflecting liners. (3) A simplified quasilinear theory including the effect of N/sub parallel/ is developed to model the electrons. An analytic expression is derived for the RF-induced pump-out of the magnetically-confined warm electrons. Results of the Fokker-Planck simulations show the development of the electron energy distribution for several plasma conditions and verify the scaling of the analytic expression for RF-induced diffusion into the loss cone. (4) Sample x-ray and endloss data are presented, and the overall comparison between the simulation and experiment is discussed. The x-ray signals indicate that, for greater RF power, the hot electrondensity increases more rapidly than its temperature. The time history of the endloss data, illustrating RF-enhancement, suggests the predicted scaling for warm-electron pump-out. Finally, a comparison between the measured and predicted energy distribution shows that the bulk, warm and hot components of the heated Constance 2 electrons are indeed reproduced by the simulation.

  10. Modeling whistler wave generation regimes in magnetospheric cyclotron maser

    Directory of Open Access Journals (Sweden)

    D. L. Pasmanik

    2004-11-01

    Full Text Available Numerical analysis of the model for cyclotron instability in the Earth's magnetosphere is performed. This model, based on the self-consistent set of equations of quasi-linear plasma theory, describes different regimes of wave generation and related energetic particle precipitation. As the source of free energy the injection of energetic electrons with transverse anisotropic distribution function to the interaction region is considered. A parametric study of the model is performed. The main attention is paid to the analysis of generation regimes for different characteristics of energetic electron source, such as the shape of pitch angle distributions and its intensity. Two mechanisms of removal of energetic electrons from a generation region are considered, one is due to the particle precipitation through the loss cone and another one is related to the magnetic drift of energetic particles.

    It was confirmed that two main regimes occur in this system in the presence of a constant particle source, in the case of precipitation losses. At small source intensity relaxation oscillations were found, whose parameters are in good agreement with simplified analytical theory developed earlier. At a larger source intensity, transition to a periodic generation occurs. In the case of drift losses the regime of self-sustained periodic generation regime is realized for source intensity higher than some threshold. The dependencies of repetition period and dynamic spectrum shape on the source parameters were studied in detail. In addition to simple periodic regimes, those with more complex spectral forms were found. In particular, alteration of spikes with different spectral shape can take place. It was also shown that quasi-stationary generation at the low-frequency band can coexist with periodic modulation at higher frequencies.

    On the basis of the results obtained, the model for explanation of

  11. Heating and Current Drive by Electron Cyclotron Waves

    Science.gov (United States)

    Prater, R.

    2003-10-01

    The physics model of electron cyclotron heating (ECH) and current drive (ECCD) is becoming well validated through systematic comparisons of theory and experiment. Work has shown that ECCD can be highly localized and robustly controlled, leading to applications including stabilization of MHD instabilities like neoclassical tearing modes, control and sustainment of desired profiles of current density and plasma pressure, and studies of localized transport. These physics applications and the study of the basic physics of ECH and ECCD were enabled by the advent of the gyrotron in the 1980s and of the diamond window for megawatt gyrotrons in the 1990s. The experimental work stimulated a broad base of theory based on first principles which is encapsulated in linear ray tracing codes and fully relativistic quasilinear Fokker-Planck codes. Recent experiments use measurements of the local poloidal magnetic field through the motional Stark effect to determine the magnitude and profile of the locally driven current. The subtle balance between wave-induced diffusion and Coulomb relaxation in velocity space provides an understanding of the effects of trapping of current-carrying electrons in the magnetic well, an effect which can be used to advantage. Strong quasilinear effects and radial transport of electrons which may broaden the driven current profile have also been observed under some conditions and appear to be consistent with theory, but in large devices these are usually insignificant. Additional advantages of ECH compared with other rf heating methods are that the antenna can be far removed from the plasma and the power density can be very high. The agreement of theory and experiment, the broad base of established applications, and the technical advantages of ECH support the application of ECH in next-step tokamaks and stellarators.

  12. The beam commissioning of BRIF and future cyclotron development at CIAE

    Science.gov (United States)

    Zhang, Tianjue; Yang, Jianjun

    2016-06-01

    As an upgrade project of the existing HI-13 tandem accelerator facility, the Beijing Radioactive Ion-beam Facility (BRIF) is being constructed in China Institute of Atomic Energy (CIAE). This project consists of an 100 MeV proton compact cyclotron, a two-stage ISOL system, a superconducting linac booster and various experimental terminals. The beam commissioning of the cyclotron was launched by the end of 2013 and on July 4, 2014 the first 100 MeV proton beam was received on a temporary target which was positioned at the outlet of the cyclotron. The beam current was stably maintained at above 25 μA for about 9 h on July 25, 2014 and the cyclotron is now ready for providing CW proton beam on target-source for RIB production. The beam current is expected to be increased to 200-500 μA in the coming years. The installation of the ISOL system is finished and the stable ion beam test shows it can reach a mass resolution better than 10,000. It is expected to generate dozens of RIB by 100 MeV proton beam. In addition, this paper also introduces the recent progress of the pre-study of an 800 MeV, 3-4 MW separate-sector proton cyclotron, which is aimed to provide high power proton beam for various applications, such as neutron and neutrino physics, proton radiography and nuclear data measurement and ADS system.

  13. Ion beam driven resonant ion-cyclotron instability in a magnetized dusty plasma

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, Ved; Vijayshri [School of Sciences, Indira Gandhi National Open University, Maidan Garhi, New Delhi 110 068 (India); Sharma, Suresh C. [Department of Applied Physics, Delhi Technological University, Shahbad Daulatpur, Bawana Road, Delhi 110 042 (India); Gupta, Ruby [Department of Physics, Swami Shraddhanand College, University of Delhi, Alipur, Delhi 110 036 (India)

    2014-03-15

    Electrostatic ion cyclotron waves are excited by axial ion beam in a dusty plasma via Cerenkov and slow cyclotron interaction. The dispersion relation of the instability is derived in the presence of positively/negatively charged dust grains. The minimum beam velocity needed for the excitation is estimated for different values of relative density of negatively charged dust grains. It is shown that the minimum beam velocity needed for excitation increases as the charge density carried by dust increases. Temperature of electrons and ions, charge and mass of dust grains, external static magnetic field and finite boundary of dusty plasma significantly modify the dispersion properties of these waves and play a crucial role in the growth of resonant ion cyclotron instability. The ion cyclotron modes with phase velocity comparable to the beam velocity possess a large growth rate. The maximum value of growth rate increases with the beam density and scales as the one-third power of the beam density in Cerenkov interaction and is proportional to the square root of beam density in slow cyclotron interaction.

  14. Predictive ion source control using artificial neural network for RFT-30 cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Young Bae, E-mail: ybkong@kaeri.re.kr; Hur, Min Goo; Lee, Eun Je; Park, Jeong Hoon; Park, Yong Dae; Yang, Seung Dae

    2016-01-11

    An RFT-30 cyclotron is a 30 MeV proton accelerator for radioisotope production and fundamental research. The ion source of the RFT-30 cyclotron creates plasma from hydrogen gas and transports an ion beam into the center region of the cyclotron. Ion source control is used to search source parameters for best quality of the ion beam. Ion source control in a real system is a difficult and time consuming task, and the operator should search the source parameters by manipulating the cyclotron directly. In this paper, we propose an artificial neural network based predictive control approach for the RFT-30 ion source. The proposed approach constructs the ion source model by using an artificial neural network and finds the optimized parameters with the simulated annealing algorithm. To analyze the performance of the proposed approach, we evaluated the simulations with the experimental data of the ion source. The performance results show that the proposed approach can provide an efficient way to analyze and control the ion source of the RFT-30 cyclotron.

  15. On the origin of cyclotron lines in the spectra of X-ray pulsars

    Directory of Open Access Journals (Sweden)

    Mushtukov A. A.

    2014-01-01

    Full Text Available Cyclotron resonance scattering features are observed in the spectra of some X-ray pulsars and show significant changes in the line energy with the pulsar luminosity. In a case of bright sources, the line centroid energy is anti-correlated with the luminosity. Such a behaviour is often associated with the onset and growth of the accretion column, which is believed to be the origin of the observed emission and the cyclotron lines. However, this scenario inevitably implies large gradient of the magnetic field strength within the line-forming region, and it makes the formation of the observed line-like features problematic. Moreover, the observed variation of the cyclotron line energy is much smaller than could be anticipated for the corresponding luminosity changes. We argue that a more physically realistic situation is that the cyclotron line forms when the radiation emitted by the accretion column is reflected from the neutron star surface. The idea is based on the facts that a substantial part of column luminosity is intercepted by the neutron star surface and the reflected radiation should contain absorption features. The reflection model is developed and applied to explain the observed variations of the cyclotron line energy in a bright X-ray pulsar V 0332+53 over a wide range of luminosities.

  16. Support vector machine based fault detection approach for RFT-30 cyclotron

    Science.gov (United States)

    Kong, Young Bae; Lee, Eun Je; Hur, Min Goo; Park, Jeong Hoon; Park, Yong Dae; Yang, Seung Dae

    2016-10-01

    An RFT-30 is a 30 MeV cyclotron used for radioisotope applications and radiopharmaceutical researches. The RFT-30 cyclotron is highly complex and includes many signals for control and monitoring of the system. It is quite difficult to detect and monitor the system failure in real time. Moreover, continuous monitoring of the system is hard and time-consuming work for human operators. In this paper, we propose a support vector machine (SVM) based fault detection approach for the RFT-30 cyclotron. The proposed approach performs SVM learning with training samples to construct the classification model. To compensate the system complexity due to the large-scale accelerator, we utilize the principal component analysis (PCA) for transformation of the original data. After training procedure, the proposed approach detects the system faults in real time. We analyzed the performance of the proposed approach utilizing the experimental data of the RFT-30 cyclotron. The performance results show that the proposed SVM approach can provide an efficient way to control the cyclotron system.

  17. The on-line low temperature nuclear orientation facility NICOLE

    Science.gov (United States)

    Ohtsubo, T.; Roccia, S.; Stone, N. J.; Stone, J. R.; Gaulard, C.; Köster, U.; Nikolov, J.; Simpson, G. S.; Veskovic, M.

    2017-04-01

    We review major experiments and results obtained by the on-line low temperature nuclear orientation method at the NICOLE facility at ISOLDE, CERN since the year 2000 and highlight their general physical impact. This versatile facility, providing a large degree of controlled nuclear polarization, was used for a long-standing study of magnetic moments at shell closures in the region Z = 28, N = 28–50 but also for dedicated studies in the deformed region around A ∼ 180. Another physics program was conducted to test symmetry in the weak sector and constrain weak coupling beyond V–A. Those two programs were supported by careful measurements of the involved solid state physics parameters to attain the full sensitivity of the technique and provide interesting interdisciplinary results. Future plans for this facility include the challenging idea of measuring the beta–gamma–neutron angular distributions from polarized beta delayed neutron emitters, further test of fundamental symmetries and obtaining nuclear structure data used in medical applications. The facility will also continue to contribute to both the nuclear structure and fundamental symmetry test programs.

  18. EXPANDING ACADEMIC VOCABULARY WITH AN INTERACTIVE ON-LINE DATABASE

    Directory of Open Access Journals (Sweden)

    Marlise Horst

    2005-05-01

    Full Text Available University students used a set of existing and purpose-built on-line tools for vocabulary learning in an experimental ESL course. The resources included concordance, dictionary, cloze-builder, hypertext, and a database with interactive self-quizzing feature (all freely available at www.lextutor.ca. The vocabulary targeted for learning consisted of (a Coxhead's (2000 Academic Word List, a list of items that occur frequently in university textbooks, and (b unfamiliar words students had met in academic texts and selected for entry into the class database. The suite of tools were designed to foster retention by engaging learners in deep processing, an aspect that is often described as missing in computer exercises for vocabulary learning. Database entries were examined to determine whether context sentences supported word meanings adequately and whether entered words reflected the unavailability of cognates in the various first languages of the participants. Pre- and post-treatment performance on tests of knowledge of words targeted for learning in the course were compared to establish learning gains. Regression analyses investigated connections between use of specific computer tools and gains.

  19. On-line catalytic upgrading of biomass fast pyrolysis products

    Institute of Scientific and Technical Information of China (English)

    LU Qiang; ZHU XiFeng; LI WenZhi; ZHANG Ying; CHEN DengYu

    2009-01-01

    Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was employed to achieve fast pyrolysis of biomass and on-line analysis of the pyrolysis vapors. Four biomass materials (poplar wood, fir wood, cotton straw and rice husk) were pyrolyzed to reveal the difference among their products. Moreover, catalytic cracking of the pyrolysis vapors from cotton straw was performed by using five catalysts, including two microporous zeolites (HZSM-5 and HY) and three mesoporous catalysts (ZrO2&TiO2, SBA-15 and AI/SBA-15). The results showed that the distribution of the pyrolytic products from the four materials differed a little from each other, while catalytic cracking could significantly alter the pyrolytic products. Those important primary pyrolytic products such as levoglucosen, hydroxyacetaldehyde and 1-hydroxy-2-propanone were decreased greatly after catalysis. The two microporous zeolites were ef-fective to generate high yields of hydrocarbons, while the three mesoporous materials favored the formation of furan, furfural and other furan compounds, as well as acetic acid.

  20. On-Line Condition Monitoring using Computational Intelligence

    CERN Document Server

    Vilakazi, C B; Mautla, P; Moloto, E

    2007-01-01

    This paper presents bushing condition monitoring frameworks that use multi-layer perceptrons (MLP), radial basis functions (RBF) and support vector machines (SVM) classifiers. The first level of the framework determines if the bushing is faulty or not while the second level determines the type of fault. The diagnostic gases in the bushings are analyzed using the dissolve gas analysis. MLP gives superior performance in terms of accuracy and training time than SVM and RBF. In addition, an on-line bushing condition monitoring approach, which is able to adapt to newly acquired data are introduced. This approach is able to accommodate new classes that are introduced by incoming data and is implemented using an incremental learning algorithm that uses MLP. The testing results improved from 67.5% to 95.8% as new data were introduced and the testing results improved from 60% to 95.3% as new conditions were introduced. On average the confidence value of the framework on its decision was 0.92.

  1. Using on-line altered auditory feedback treating Parkinsonian speech

    Science.gov (United States)

    Wang, Emily; Verhagen, Leo; de Vries, Meinou H.

    2005-09-01

    Patients with advanced Parkinson's disease tend to have dysarthric speech that is hesitant, accelerated, and repetitive, and that is often resistant to behavior speech therapy. In this pilot study, the speech disturbances were treated using on-line altered feedbacks (AF) provided by SpeechEasy (SE), an in-the-ear device registered with the FDA for use in humans to treat chronic stuttering. Eight PD patients participated in the study. All had moderate to severe speech disturbances. In addition, two patients had moderate recurring stuttering at the onset of PD after long remission since adolescence, two had bilateral STN DBS, and two bilateral pallidal DBS. An effective combination of delayed auditory feedback and frequency-altered feedback was selected for each subject and provided via SE worn in one ear. All subjects produced speech samples (structured-monologue and reading) under three conditions: baseline, with SE without, and with feedbacks. The speech samples were randomly presented and rated for speech intelligibility goodness using UPDRS-III item 18 and the speaking rate. The results indicted that SpeechEasy is well tolerated and AF can improve speech intelligibility in spontaneous speech. Further investigational use of this device for treating speech disorders in PD is warranted [Work partially supported by Janus Dev. Group, Inc.].

  2. The Efficiency of the On-line Samplings

    Directory of Open Access Journals (Sweden)

    Ileana Gabriela NICULESCU-ARON

    2006-01-01

    Full Text Available The rapid growth of the technology from the last decades led to the collateral development of many other sciences. One of the most important inventions was the Internet and the web technologies with a tremendous impact on the society. Statistics, as a social science, at its turn in ongoing development has only to gain from that. Lately, the on line sampling technique greatly developed. Each web site of a certain importance includes in various forms of the questionnaires. These vary from a mere question to lengthy ones and are a part of daily life of those who access the World Wide Web. The main question is how feasible are the results derived from these samplings as the main issue is the representativiness. A nonrepresentative sampling is a futile one. It is a more convenient solution to post a question on the web page and to wait for an answer from the page’s visitors? But how representative is this answer for the target audience? The present paper aims to list the on-lone methodology as well as analyze their efficiency through presenting their advantages and drawbacks.

  3. Chromatographic on-line detection of bioactives in food

    Directory of Open Access Journals (Sweden)

    Remmelt Van der Werf

    2013-08-01

    Full Text Available ABSTRACTFindings were focused on the anti-oxidative activity of numerous fruits and vegetables by means of an on-line HPLC radical scavenging detection method. The reactant used was the ABTS•+ green radical cation. The system has been optimized in terms of reactor design, and chemical reactions kinetics. It has been qualified to classify molecules in order of their increasing activity to scavenge exogenous radicals. It may be used as a powerful high resolution screening tool to investigate the radical scavenging activities of natural plants. Bioassays consisting in cellular in vitro antioxidant assay using pancreatic β-cells have been used to confirm the bioactivity of the selected micronutrients. This study demonstrated that it is possible to screen at the molecular level, the bioactivity of numerous natural samples and to point out the richness of the local biodiversity in terms of natural resource of functional food ingredients usable for their potential benefits for consumer’s health, wellbeing and wellaging.Key words: HPLC radical scavenging detection method, bioactivity of natural samples

  4. On-line range images registration with GPGPU

    Science.gov (United States)

    Będkowski, J.; Naruniec, J.

    2013-03-01

    This paper concerns implementation of algorithms in the two important aspects of modern 3D data processing: data registration and segmentation. Solution proposed for the first topic is based on the 3D space decomposition, while the latter on image processing and local neighbourhood search. Data processing is implemented by using NVIDIA compute unified device architecture (NIVIDIA CUDA) parallel computation. The result of the segmentation is a coloured map where different colours correspond to different objects, such as walls, floor and stairs. The research is related to the problem of collecting 3D data with a RGB-D camera mounted on a rotated head, to be used in mobile robot applications. Performance of the data registration algorithm is aimed for on-line processing. The iterative closest point (ICP) approach is chosen as a registration method. Computations are based on the parallel fast nearest neighbour search. This procedure decomposes 3D space into cubic buckets and, therefore, the time of the matching is deterministic. First technique of the data segmentation uses accele-rometers integrated with a RGB-D sensor to obtain rotation compensation and image processing method for defining pre-requisites of the known categories. The second technique uses the adapted nearest neighbour search procedure for obtaining normal vectors for each range point.

  5. Development of on-line laser power monitoring system

    Science.gov (United States)

    Ding, Chien-Fang; Lee, Meng-Shiou; Li, Kuan-Ming

    2016-03-01

    Since the laser was invented, laser has been applied in many fields such as material processing, communication, measurement, biomedical engineering, defense industries and etc. Laser power is an important parameter in laser material processing, i.e. laser cutting, and laser drilling. However, the laser power is easily affected by the environment temperature, we tend to monitor the laser power status, ensuring there is an effective material processing. Besides, the response time of current laser power meters is too long, they cannot measure laser power accurately in a short time. To be more precisely, we can know the status of laser power and help us to achieve an effective material processing at the same time. To monitor the laser power, this study utilize a CMOS (Complementary metal-oxide-semiconductor) camera to develop an on-line laser power monitoring system. The CMOS camera captures images of incident laser beam after it is split and attenuated by beam splitter and neutral density filter. By comparing the average brightness of the beam spots and measurement results from laser power meter, laser power can be estimated. Under continuous measuring mode, the average measuring error is about 3%, and the response time is at least 3.6 second shorter than thermopile power meters; under trigger measuring mode which enables the CMOS camera to synchronize with intermittent laser output, the average measuring error is less than 3%, and the shortest response time is 20 millisecond.

  6. Virtual laboratories: Collaborative environments and facilities-on-line

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, C.E. Jr. [Oak Ridge National Lab., TN (United States). I and C Div.; Cavallini, J.S.; Seweryniak, G.R.; Kitchens, T.A.; Hitchcock, D.A.; Scott, M.A.; Welch, L.C. [Dept. of Energy, Germantown, MD (United States). Mathematical Information, and Computational Sciences Div.; Aiken, R.J. [Dept. of Energy, Germantown, MD (United States). Mathematical Information, and Computational Sciences Div.]|[Lawrence Livermore National Lab., CA (United States); Stevens, R.L. [Argonne National Lab., IL (United States). Mathematics and Computer Sciences Div.

    1995-07-01

    The Department of Energy (DOE) has major research laboratories in a number of locations in the US, typically co-located with large research instruments or research facilities valued at tens of millions to even billions of dollars. Present budget exigencies facing the entire nation are felt very deeply at DOE, just as elsewhere. Advances over the last few years in networking and computing technologies make virtual collaborative environments and conduct of experiments over the internetwork structure a possibility. The authors believe that development of these collaborative environments and facilities-on-line could lead to a ``virtual laboratory`` with tremendous potential for decreasing the costs of research and increasing the productivity of their capital investment in research facilities. The majority of these cost savings would be due to increased productivity of their research efforts, better utilization of resources and facilities, and avoiding duplication of expensive facilities. A vision of how this might all fit together and a discussion of the infrastructure necessary to enable these developments is presented.

  7. Status report of the Jyvaskyla ion guide isotope separator on-line facility

    NARCIS (Netherlands)

    Penttila, H; Dendooven, P; Honkanen, A; Huhta, M; Jauho, PP; Jokinen, A; Lhersonneau, G; Oinonen, M; Parmonen, JM; Perajarvi, K; Aysto, J

    1997-01-01

    The ion guide isotope separator facility IGISOL of the University of Jyvaskyla has been moved to the new K-130 heavy ion cyclotron laboratory. The totally reconstructed facility is described in detail. The primary beams and targets, helium pumping, separator beam line construction and separator beam

  8. Central region design for a 10 MeV internal ion source cyclotron

    Institute of Scientific and Technical Information of China (English)

    QIN Bin; LIU Kai-Feng; FENG Yi-Zhang; FAN Ming-Wu

    2009-01-01

    Internal ion sources are widely adopted in commercial cyclotrons used for short-life isotopes produc-tion. Without beam manipulation provided by the external beam injection line, the central region of this type of cyclotron is more sensitive and should be carefully designed. A design study and beam dynamics simulation for the central region of a 10 MeV compact cyclotron is presented. The OPERA3D/TOSCA code was used to calculate the electric field from a parameterized three dimensional (3D) central region model. With iterative structure optimizations of the central region, the beam centering and vertical focusing is well controlled, and the RF phase acceptance is around 25° A c++ code for beam simulation in the central region was developed and tested.

  9. Ensemble Simulations of Proton Heating in the Solar Wind via Turbulence and Ion Cyclotron Resonance

    CERN Document Server

    Cranmer, Steven R

    2014-01-01

    Protons in the solar corona and heliosphere exhibit anisotropic velocity distributions, violation of magnetic moment conservation, and a general lack of thermal equilibrium with the other particle species. There is no agreement about the identity of the physical processes that energize non-Maxwellian protons in the solar wind, but a traditional favorite has been the dissipation of ion cyclotron resonant Alfven waves. This paper presents kinetic models of how ion cyclotron waves heat protons on their journey from the corona to interplanetary space. It also derives a wide range of new solutions for the relevant dispersion relations, marginal stability boundaries, and nonresonant velocity-space diffusion rates. A phenomenological model containing both cyclotron damping and turbulent cascade is constructed to explain the suppression of proton heating at low alpha-proton differential flow speeds. These effects are implemented in a large-scale model of proton thermal evolution from the corona to 1 AU. A Monte Carlo...

  10. Excitation of ion-cyclotron harmonic waves in lower-hybrid heating

    Science.gov (United States)

    Villalon, E.

    1981-06-01

    The parametric excitation of ion-cyclotron waves by a lower-hybrid pump field is studied in the assumption that the magnitude of the pump is constant. The spatial amplification factor is given as a function of the wavenumber mismatch as produced by the plasma density gradient, and of the linear damping rates of the excited ion-cyclotron and sideband waves. The analysis is applied to plasma edge parameters relevant to the JFT2 heating experiment. It is found that ion-cyclotron harmonic modes are excited depending on pump frequency and plasma density. These modes are shown to have finite damping rates. The parallel refractive indices n1z of the excited sideband fields are found to be always larger than that of the driven pump field. Transition to quasi-mode decay occurs either by decreasing the pump frequency or by increasing the applied RF-power.

  11. The study of acceptance and the transmission efficiency of separated sector cyclotron

    Directory of Open Access Journals (Sweden)

    Li Xiaoni

    2015-01-01

    Full Text Available In this paper we present the study of the transversal and longitudinal acceptance and the transmission efficiency in the injection, acceleration, and extraction systems in the separated sector cyclotron of the heavy ion research facility in Lanzhou, China. The study of cyclotron acceptance is done for 238U36+ with energy of 97 MeV/u and for 70Zn10+ with energy of 5.62 MeV/u under the theoretical isochronous and real magnetic field distribution. From the simulation results it can be seen that the transmission efficiency and the acceptances of separated sector cyclotron can be improved by redesign the curvature of MSI3 deflector or by introducing the magnet shim in MSI3 deflector region to change the distribution of the inner magnetic field. [Projekat Ministarstva nauke Republike Srbije, br. OI-171018

  12. Improving cancer treatment with cyclotron produced radionuclides. Comprehensive progress report, February 1, 1990--January 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Larson, S.M. Finn, R.D.

    1992-08-04

    This report describes the author`s continuing long term goal of promoting nuclear medicine applications by improving the scientific basis for tumor diagnosis treatment and treatment follow-up based on the use of cyclotron produced radiotracers in oncology. The program has 3 interactive components: Radiochemistry /Cyclotron; Pharmacology; and Immunology. An essential strategy is as follows: novel radionuclides and radiotracers developed in the Radiochemistry/Cyclotron section under the DOE grant during the 1989--1992 grant period, will be employed in the Pharmacology and Immunology sections of the DOE grant during the 1992--1995 grant period. The development of novel radionuclides and tracers is of course useful in and of itself, but their utility is greatly enhanced by the interaction with the immunology and pharmacology components of the program.

  13. Production parameters of the therapeutic 105Rh radionuclide using medium energy cyclotron

    Indian Academy of Sciences (India)

    Mayeen Uddin Khandaker; Kwangsoo Kim; Guinyun Kim

    2012-08-01

    Production cross-sections of the therapeutic 105Rh radionuclide from proton-induced reactions on natural palladium target were measured using stacked-foil activation technique combined with high resolution -ray spectrometry at the MC50 cyclotron of the Korea Institute of Radiological and Medical Sciences. Note that cyclotron production of the 105Rh radionuclide from natural palladium target was measured here for the first time. Results are compared with the theoretical values obtained using the model codes TALYS and ALICE-IPPE. Thick target integral yields for the investigated 105Rh radionuclide were deduced from the threshold energy to 40 MeV. Measured data of the 105Rh radionuclide are important because of its potential applications in nuclear medicine and/or therapeutic purposes. Optimal production circumstances for the therapeutic 105Rh radionuclide using a cyclotron are discussed elaborately.

  14. Design and Experimental Study of the External H~- Ion Source for a 10 MeV Medical Cyclotron

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A 10 MeV medical cyclotron has been designed by the BRIF Division at CIAE, for which the H- beam is axially injected to the machine. To satisfy the requirement for the cyclotron with H- ion source, a compact multicusp H- ion source has

  15. Worldwide On-line Distance Learning University Astronomy

    Science.gov (United States)

    Eyres, S. P. S.; Hassall, B. J. M.; Butchart, I.; Bromage, G. E.

    2006-08-01

    The University of Central Lancashire operates a suite of distance learning courses in Astronomy, available both on-line and via CD-ROM. The courses are available worldwide, and emphasise flexibility of study. To this end students can study anything from a single module (1/6^th of a full year at degree level) all the way up to an entire degree entirely by distance learning. Study rates vary from one to four modules each year, and students can move on to Level 2 modules (equivalent to second year level in a UK degree) before completing the full set of Level 1 modules. Over 1000 awards have been made to date. The core syllabus is Astronomy and Cosmology at Level 1, alongside skills in literature research, using computers, and basic observing. We also offer a basic history of European astronomy. At Level 2 we look at the astrophysics of the Sun, the stars, and galaxies including the Milky Way. By Level 3 students are expected to engage in a large individual project, and a collaborative investigation with other students, alongside high-level courses in cosmology, relativity, extreme states of matter and the origins of the elements, life and astronomical objects. While many students are retired people looking to exercise their brains, keen amateur amateurs or professionals with disposable incomes, and significant fraction are teachers seeking to improve their subject knowledge or high school students gaining an edge in the UK University entrance competition. Via our involvement with SALT we offer our courses to members of previously disadvantaged communities. This leads to an incredibly diverse and lively student body.

  16. Cyclotron resonance of figure-of-eight orbits in a type-II Weyl semimetal

    Science.gov (United States)

    Koshino, Mikito

    2016-07-01

    We study the cyclotron resonance in the electron-hole joint Fermi surface of a type-II Weyl semimetal. In magnetic field, the electron and hole pockets touching at the Weyl node are hybridized to form quantized Landau levels corresponding to semiclassical 8-shaped orbits. We calculate the dynamical conductivities for the electric fields oscillating in x and y directions and find that the resonant frequencies in x and y differ by a factor of two, reflecting the figure-of-eight electron motion in real space. The peculiar anisotropy in the cyclotron resonance serves as a unique characteristic of the dumbbell-like Fermi surface.

  17. Beam Loss by Lorentz Stripping in a 100 MeV Compact H~- Cyclotron

    Institute of Scientific and Technical Information of China (English)

    Larry; Root

    2002-01-01

    The success of TRIUMF’s ISAC facility demonstrates that a 500 MeV 100 μ A H cyclotron is agood choice for the driver stage of an ISOL type RIB facility. As a result, China Institute of AtomicEnergy is proposing the construction of a 75~100 MeV 200~500μA H~- cyclotron as an upgrade to theBeijing Tandem Laboratory. This would be a multiple user facility, which would include a RIB target

  18. The electrostatic ion-cyclotron instability-a two-dimensional potential relaxation instability

    DEFF Research Database (Denmark)

    Popa, G.; Schrittwieser, R.; Juul Rasmussen, Jens;

    1985-01-01

    An experimental investigation shows that the electrostatic ion-cyclotron instability, driven by an electron current to a positively biased collector, is accompanied by strong coherent two-dimensional fluctuations of the plasma potential in front of the collector. These results suggest that this i......An experimental investigation shows that the electrostatic ion-cyclotron instability, driven by an electron current to a positively biased collector, is accompanied by strong coherent two-dimensional fluctuations of the plasma potential in front of the collector. These results suggest...

  19. Development of an 18 GHz superconducting electron cyclotron resonance ion source at RCNP.

    Science.gov (United States)

    Yorita, Tetsuhiko; Hatanaka, Kichiji; Fukuda, Mitsuhiro; Kibayashi, Mitsuru; Morinobu, Shunpei; Okamura, Hiroyuki; Tamii, Atsushi

    2008-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source has recently been developed and installed in order to extend the variety and the intensity of ions at the RCNP coupled cyclotron facility. Production of several ions such as O, N, Ar, Kr, etc., is now under development and some of them have already been used for user experiments. For example, highly charged heavy ion beams like (86)Kr(21+,23+) and intense (16)O(5+,6+) and (15)N(6+) ion beams have been provided for experiments. The metal ion from volatile compounds method for boron ions has been developed as well.

  20. Purification of cyclotron-produced {sup 203}Pb for labeling Herceptin

    Energy Technology Data Exchange (ETDEWEB)

    Garmestani, Kayhan [Radioimmune and Inorganic Chemistry Section, Radiation Oncology Branch, NCI, Bethesda, MD 20892-1002 (United States); Milenic, Diane E. [Radioimmune and Inorganic Chemistry Section, Radiation Oncology Branch, NCI, Bethesda, MD 20892-1002 (United States); Brady, Erik D. [Radioimmune and Inorganic Chemistry Section, Radiation Oncology Branch, NCI, Bethesda, MD 20892-1002 (United States); Plascjak, Paul S. [PET Department, Clinical Center, NIH, Bethesda, MD 20892-1002 (United States); Brechbiel, Martin W. [Radioimmune and Inorganic Chemistry Section, Radiation Oncology Branch, NCI, Bethesda, MD 20892-1002 (United States)]. E-mail: martinwb@mail.nih.gov

    2005-04-01

    A simple and rapid procedure was developed for the purification of cyclotron-produced {sup 203}Pb via the {sup 203}Tl(d,2n) {sup 203}Pb reaction. A Pb(II) selective ion-exchange resin, with commercial name Pb Resin from Eichrom Technologies, Inc., was used to purify {sup 203}Pb from the cyclotron-irradiated Tl target with excellent recovery of the enriched Tl target material. The purified {sup 203}Pb was used to radiolabel the monoclonal antibody Herceptin. The in vitro and in vivo properties of the {sup 203}Pb radioimmunoconjugate were evaluated.

  1. First results of electron cyclotron emission measurements at the GDT magnetic mirror

    CERN Document Server

    Shalashov, A G; Gospodchikov, E D; Lubyako, L V; Yakovlev, D V; Bagryansky, P A

    2016-01-01

    This paper summarizes the results of experiments on electron cyclotron emission (ECE) measurements at the fundamental harmonic recently performed at the axially symmetric magnetic mirror device GDT (Budker Institute, Novosibirsk). New ECE diagnostics is installed to facilitate the successful electron cyclotron resonance heating experiment and operates in the vicinity of the heating frequency of 54.5 GHz. Besides expected emission of thermal electrons, a clearly resolved non-thermal ECE is observed indicating the presence of suprathermal electrons driven by high-power microwave heating. The particulars of plasma emission are studied experimentally in a broad range of discharge scenarios.

  2. Cyclotron resonance in InAs/GaSb heterostructure in inclined magnetic field

    CERN Document Server

    Greshnov, A A; Vasilev, Yu B; Suchalkin, S D; Meltser, B Y; Ivanov, S V; Kopev, P S

    2002-01-01

    The mechanism of splitting the cyclotron resonance line in the InAs/GaSb heterostructure in the inclined magnetic field is experimentally and theoretically studied. It is shown that the electrons and holes mixing in leads to the anticrossing Landau levels and consequently to the cyclotron resonance line splitting. Splitting in the case of the inclined magnetic field was not observed which is explained by damping the electrons and holes states mixing in on the account of originating the additional barrier for the electrons and holes by availability of the magnetic field longitudinal constituent

  3. Nonlinear sub-cyclotron resonance as a formation mechanism for gaps in banded chorus

    CERN Document Server

    Fu, Xiangrong; Dong, Chuanfei; Gary, S Peter

    2015-01-01

    An interesting characteristic of magnetospheric chorus is the presence of a frequency gap at $\\omega \\simeq 0.5\\Omega_e$, where $\\Omega_e$ is the electron cyclotron angular frequency. Recent chorus observations sometimes show additional gaps near $0.3\\Omega_e$ and $0.6\\Omega_e$. Here we present a novel nonlinear mechanism for the formation of these gaps using Hamiltonian theory and test-particle simulations in a homogeneous, magnetized, collisionless plasma. We find that an oblique whistler wave with frequency at a fraction of the electron cyclotron frequency can resonate with electrons, leading to effective energy exchange between the wave and particles.

  4. Cyclotron resonance in two-dimensional electron system with self-organized antidots

    CERN Document Server

    Suchalkin, S D; Zundel, M; Nachtwei, G; Klitzing, K V; Eberl, K

    2001-01-01

    The data on the experimental study on the cyclotron resonance in the two-dimensional electron system with the random scattering potential, conditioned by the massif of the AlInAs self-organized quantum islands, formed in the AlGaAs/GaAs heterotransition plane, are presented. The sharp narrowing of the cyclotron resonance with increase in the magnetic field, explained by the charge scattering peculiarities in the given potential is established. The obtained results suggest the strongly correlated electron state in the strong magnetic fields by the carriers concentrations lesser than the antidots concentrations

  5. Biomedical research with cyclotron produced radionuclides. Progress report, October 1, 1977--September 30, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Laughlin, J.S.; Benua, R.S.; Tilbury, R.S.; Bigler, R.E.

    1978-09-30

    Progress is reported on biomedical studies using cyclotron-produced /sup 18/F, /sup 15/O, /sup 11/C, /sup 13/N, /sup 52/Fe, /sup 38/K, /sup 206/Bi, /sup 73/Se, /sup 53/Co, and /sup 43/K. The following research projects are described: tumor detection and diagnosis; neurological studies; radiopharmaceutical development; /sup 38/K as an indicator of blood flow to the myocardium; dosimetry for internally deposited isotopes in animals and man; cyclotron development; positron tomographic imaging with the TOKIM System; and review of positron emission transaxial tomograph instruments. (HLW)

  6. Ordinary-mode fundamental electron cyclotron resonance absorption and emission in the Princeton Large Torus

    Energy Technology Data Exchange (ETDEWEB)

    Efthimion, P.C.; Arunasalam, V.; Hosea, J.C.

    1979-11-01

    Fundamental electron cyclotron resonance damping for 4 mm waves with ordinary polarization is measured for propagation along the major radius traversing the midplane of the plasma in the Princeton Large Torus (PLT). Optical depths obtained from the data are in good agreement with those predicted by the relativistic hot plasma theory. Near blackbody emission over much of the plasma midplane is obtained and, in conjunction with the damping measurements, indicates that the vessel reflectivity is high. The practical use of ordinary mode fundamental electron cyclotron resonance heating (ECRH) in existing and future toroidal devices is supported by these results.

  7. New Cyclotron Targetry to Enhance F-18 clinical Position Emission Tomography

    Energy Technology Data Exchange (ETDEWEB)

    J. Michael Doster

    2008-12-19

    This project proposes to develop cyclotron targets that produce F-18 for clinical Positron Emission Tomography (PET) at significantly higher rates than that available from current targetry. This production rate of 18F is directly proportional to the beam current. Higher beam currents would result in increased 18F production but would be accompanied by higher heat loads to the target. The beam power available in most commercial cyclotrons exceeds the heat removal capacity of current target technology by a factor of two to four, significantly limiting the production rate of Fluorine-18.

  8. Solid targets for production of radioisotopes with cyclotron; Blancos solidos para produccion de radioisotopos con ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.; Balcazar G, M. [Instituto Nacional de Investigaciones Nucleares, Direccion de Investigacion Tecnologica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    The design of targets for production of radioisotopes and radiopharmaceuticals of cyclotron to medical applications requires a detailed analysis of several variables such as: cyclotron operation conditions, choice of used materials as target and their physicochemical characteristics, activity calculation, the yielding of each radioisotope by irradiation, the competition of nuclear reactions in function of the projectiles energy and the collision processes amongst others. The objective of this work is to determine the equations for the calculation for yielding of solid targets at the end of the proton irradiation. (Author)

  9. Space Charge Limits in the Dae$\\delta$alus DIC Compact Cyclotron

    CERN Document Server

    Baartman, Rick

    2016-01-01

    The Dae$\\delta$alus DIC compact cyclotron is proposed to achieve an extracted current of 5 mA of singly-charged hydrogen molecules, even though unlike other compact cyclotrons, the extraction is not by stripping. The authors of the proposal consistently use perveance as a scaling argument that such high current is possible. The argument is shown to be incorrect and a realistic limit is calculated. This limit is likely about 0.2 mA and certainly no higher than 0.5 mA.

  10. Kinetic instabilities in pulsed operation mode of a 14 GHz electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, O., E-mail: olli.tarvainen@jyu.fi; Kalvas, T.; Koivisto, H.; Komppula, J.; Kronholm, R.; Laulainen, J. [Department of Physics, University of Jyväskylä, 40500 Jyväskylä (Finland); Izotov, I.; Mansfeld, D. [Institute of Applied Physics, RAS, 46 Ul‘yanova St., 603950 Nizhny Novgorod (Russian Federation); Skalyga, V. [Institute of Applied Physics, RAS, 46 Ul‘yanova St., 603950 Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina St., 603950 Nizhny Novgorod (Russian Federation)

    2016-02-15

    The occurrence of kinetic plasma instabilities is studied in pulsed operation mode of a 14 GHz A-electron cyclotron resonance type electron cyclotron resonance ion source. It is shown that the temporal delay between the plasma breakdown and the appearance of the instabilities is on the order of 10-100 ms. The most important parameters affecting the delay are magnetic field strength and neutral gas pressure. It is demonstrated that kinetic instabilities limit the high charge state ion beam production in the unstable operating regime.

  11. High harmonics of the cyclotron resonance in a weak magnetic field

    Science.gov (United States)

    Gramada, A.; Raikh, M. E.

    1998-03-01

    Harmonics of the cyclotron resonance have their origin in the disorder-induced mixing of the Landau levels which leads to the violation of the Kohn theorem. In a strong magnetic field, ω_cτ>> 1, (ωc is the cyclotron frequency and τ is the relaxation time) the amplitudes of the harmonics, σ^n, fall off rapidly^1 with the number n: σ^n∝ n-2. We have studied theoretically the opposite case, ω_cτPhys. Soc. Japan, 38, 989 (1975). 2. M. A. Zudov, R. R. Du, J. A. Simmons, J. L. Reno, preprint cond-mat/9711149.

  12. Field structure and electron life times in the MEFISTO electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Bodendorfer, M. [EPFL - Ecole Polytechnique Federale de Lausanne (Switzerland); University of Berne, Institute of Physics, Space Research and Planetary Sciences, Siedlerstrasse 5, 3012 Berne (Switzerland)], E-mail: michael.bodendorfer@space.unibe.ch; Altwegg, K. [University of Berne, Institute of Physics, Space Research and Planetary Sciences, Siedlerstrasse 5, 3012 Berne (Switzerland); Shea, H. [EPFL - Ecole Polytechnique Federale de Lausanne (Switzerland); Wurz, P. [University of Berne, Institute of Physics, Space Research and Planetary Sciences, Siedlerstrasse 5, 3012 Berne (Switzerland)

    2008-03-15

    The complex magnetic field of the permanent magnet electron cyclotron resonance (ECR) ion source MEFISTO located at the University of Berne has been numerically simulated. For the first time the magnetized volume qualified for electron cyclotron resonance at 2.45 GHz and 87.5 mT has been analyzed in highly detailed 3D simulations with unprecedented resolution. New results were obtained from the numerical simulation of 25,211 electron trajectories. The evident characteristic ion sputtering trident of hexapole confined ECR ion sources has been identified with the field and electron trajectory distribution. Furthermore, unexpected long electron trajectory lifetimes were found.

  13. Field structure and electron life times in the MEFISTO electron cyclotron resonance ion source

    Science.gov (United States)

    Bodendorfer, M.; Altwegg, K.; Shea, H.; Wurz, P.

    2008-03-01

    The complex magnetic field of the permanent magnet electron cyclotron resonance (ECR) ion source MEFISTO located at the University of Berne has been numerically simulated. For the first time the magnetized volume qualified for electron cyclotron resonance at 2.45 GHz and 87.5 mT has been analyzed in highly detailed 3D simulations with unprecedented resolution. New results were obtained from the numerical simulation of 25,211 electron trajectories. The evident characteristic ion sputtering trident of hexapole confined ECR ion sources has been identified with the field and electron trajectory distribution. Furthermore, unexpected long electron trajectory lifetimes were found.

  14. Field structure and electron life times in the MEFISTO Electron Cyclotron Resonance Ion Source

    CERN Document Server

    Bodendorfer, Michael; Shea, Herbert; Wurz, Peter

    2008-01-01

    The complex magnetic field of the permanent-magnet electron cyclotron resonance (ECR) ion source MEFISTO located at the University of Bern have been numerically simulated. For the first time the magnetized volume qualified for electron cyclotron resonance at 2.45 GHz and 87.5 mT has been analyzed in highly detailed 3D simulations with unprecedented resolution. New results were obtained from the numerical simulation of 25211 electron trajectories. The evident characteristic ion sputtering trident of hexapole confined ECR sources has been identified with the field and electron trajectory distribution. Furthermore, unexpected long electron trajectory lifetimes were found.

  15. Second-harmonic ion cyclotron resonance heating scenarios of Aditya tokamak plasma

    Indian Academy of Sciences (India)

    Asim Kumar Chattopadhyay; S V Kulkarni; R Srinivasan; Aditya Team

    2015-10-01

    Plasma heating with the fast magnetosonic waves in the ion cyclotron range of frequencies (ICRF) is one of the auxiliary heating schemes of Aditya tokamak. Numerical simulation of second-harmonic resonance heating scenarios in low-temperature, low-density Aditya plasma has been carried out for fast magnetosonic wave absorption in ICRF range, using full-wave ion cyclotron heating code TORIC combined with Fokker–Planck quasilinear solver SSFPQL and the results are explained. In such low-temperature, low-density plasma, ion absorption for second-harmonic resonance heating is less but significant amount of direct electron heating is observed.

  16. Magnetic signatures of ion cyclotron waves during Cassini's high-inclination orbits of Saturn

    Science.gov (United States)

    Meeks, Zachary; Simon, Sven

    2017-02-01

    Based on magnetic field data from Cassini's high-inclination orbits of Saturn (radius RS = 60 , 268 km), we analyze the latitudinal distribution of ion cyclotron waves in the giant planet's magnetosphere. Our survey takes into account magnetic field data from all high-inclination orbits between 2004 and 2015. We analyze the dependency of the occurrence rate and amplitude of the ion cyclotron waves on radial distance ρ to Saturn's rotation axis, vertical distance z to Saturn's equatorial plane, and magnetic latitude λ. The occurrence rate of ion cyclotron waves is approximately 100% in Saturn's equatorial plane between the orbits of Enceladus and Dione and decreases to 50% at altitudes of | z | ≈ 0.6RS . Ion cyclotron waves were detected up to | z | = 2.0RS . The occurrence rate displays strong, non-monotonic variations with respect to ρ, z, and λ. The vertical amplitude profile of the waves exhibits an M-like pattern with two distinct peaks near z = ± 0.3RS and the central minimum at z=0. Compared to earlier observations, we find this M-like structure to be inflated in±z direction by a factor of three. The available magnetic field data provides only weak evidence for a local impact of Enceladus and Dione on the ion cyclotron wave field. Using the observed Doppler shift of the ion cyclotron wave frequency during Cassini's high-inclination orbits, we demonstrate the existence of a narrow band of bidirectional wave propagation. This band is centered around Saturn's equatorial plane and possesses a half-width of | z | = 0.15RS , which agrees well with the vertical scale height of Saturn's neutral cloud. To the north of this band, all ion cyclotron waves propagate towards the north (z > 0); and to the south, all waves propagate towards the south (z < 0). In companion with our previous study (Meeks et al., 2016), this survey provides the complete three-dimensional picture of the ion cyclotron wave field between the orbits of Enceladus and Rhea during the Cassini

  17. Narrow heavy-hole cyclotron resonances split by the cubic Rashba spin-orbit interaction in strained germanium quantum wells

    Science.gov (United States)

    Failla, M.; Myronov, M.; Morrison, C.; Leadley, D. R.; Lloyd-Hughes, J.

    2015-07-01

    The spin-orbit interaction was found to split the cyclotron resonance of heavy holes confined in high-mobility, compressively strained germanium quantum wells. The interference between coherent spin-split cyclotron resonances was tracked on picosecond time scales using terahertz time-domain spectroscopy. Analysis in the time domain, or using a time-frequency decomposition based on the Gabor-Morlet wavelet, was necessary when the difference between cyclotron frequencies was comparable to the linewidth. The cubic Rashba spin-orbit coefficient β was determined via two methods: (i) the magnetic-field dependence of the cyclotron frequencies, and (ii) the spin-resolved subband densities. An enhanced β and spin polarization was created by tailoring the strain to enhance the spin-orbit interaction. The amplitude modulation of the narrow, interfering cyclotron resonances is a signature of spin coherences persisting for more than 10 ps.

  18. Looking for an Alternative.

    Science.gov (United States)

    Kennedy, Jack

    1999-01-01

    Argues that high school newspapers might do well to create stronger ties with alternative weeklies. Discusses issues of niche marketing, alternative content, and alternative presentation. Notes that high school papers could learn a lot from alternative newspapers. (SR)

  19. On-line Geoscience Data Resources for Today's Undergraduates

    Science.gov (United States)

    Goodwillie, A. M.; Ryan, W.; Carbotte, S.; Melkonian, A.; Coplan, J.; Arko, R.; O'Hara, S.; Ferrini, V.; Leung, A.; Bonckzowski, J.

    2008-12-01

    Broadening the experience of undergraduates can be achieved by enabling free, unrestricted and convenient access to real scientific data. With funding from the U.S. National Science Foundation, the Marine Geoscience Data System (MGDS) (http://www.marine-geo.org/) serves as the integrated data portal for various NSF-funded projects and provides free public access and preservation to a wide variety of marine and terrestrial data including rock, fluid, biology and sediment samples information, underway geophysical data and multibeam bathymetry, water column and multi-channel seismics data. Users can easily view the locations of cruise tracks, sample and station locations against a backdrop of a multi-resolution global digital elevation model. A Search For Data web page rapidly extracts data holdings from the database and can be filtered on data and device type, field program ID, investigator name, geographical and date bounds. The data access experience is boosted by the MGDS use of standardised OGC-compliant Web Services to support uniform programmatic interfaces. GeoMapApp (http://www.geomapapp.org/), a free MGDS data visualization tool, supports map-based dynamic exploration of a broad suite of geosciences data. Built-in land and marine data sets include tectonic plate boundary compilations, DSDP/ODP core logs, earthquake events, seafloor photos, and submersible dive tracks. Seamless links take users to data held by external partner repositories including PetDB, UNAVCO, IRIS and NGDC. Users can generate custom maps and grids and import their own data sets and grids. A set of short, video-style on-line tutorials familiarises users step- by-step with GeoMapApp functionality (http://www.geomapapp.org/tutorials/). Virtual Ocean (http://www.virtualocean.org/) combines the functionality of GeoMapApp with a 3-D earth browser built using the NASA WorldWind API for a powerful new data resource. MGDS education involvement (http://www.marine-geo.org/, go to Education tab

  20. Dual electrospray ionization source for confident generation of accurate mass tags using liquid chromatography Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Nepomuceno, Angelito I; Muddiman, David C; Bergen, H Robert; Craighead, James R; Burke, Michael J; Caskey, Patrick E; Allan, Jonathan A

    2003-07-15

    Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) has rapidly established a prominent role in proteomics because of its unparalleled resolving power, sensitivity and ability to achieve high mass measurement accuracy (MMA) simultaneously. However, space-charge effects must be quantitatively, routinely, and confidently corrected because they are known to profoundly influence MMA. We argue that the most effective way to account for space-charge effects is to introduce an internal mass calibrant (IMC) using a dual electrospray ionization (ESI) source where the IMC is added from a separate ESI emitter. The major disadvantage of our initial dual ESI source to achieve high MMA, and arguably the only one, was the time required to switch between the analyte emitter and IMC emitter (i.e., >300 ms). While this "switching time" was acceptable for direct infusion experiments, it did not lend itself to high-throughput applications or when conducting on-line liquid separations. In this report, we completely redesigned the dual ESI source and demonstrate several key attributes. First, the new design allows for facile alignment of ESI emitters, undetectable vibration, and the ability to extend to multiple emitters. Second, the switching time was reduced to IMC to be accumulated "simultaneously" in the external ion reservoir and injected as a single ion packet into the ion cyclotron resonance cell, eliminating the need for a separate accumulation and ion injection event for the IMC. Third, by using a high concentration of the IMC, the residence time on this emitter could be reduced to approximately 80 ms, allowing for more time spent accumulating analyte ions of significantly lower concentration. Fourth, multiplexed on-line separations can be carried out providing increased throughput. Specifically, the new dual ESI source has demonstrated its ability to produce a stable ion current over a 45-min time period at 7 T resulting in mass accuracies of 1.08 ppm +/- 0

  1. Electromagnetic waves near the proton cyclotron frequency in the solar wind

    Science.gov (United States)

    Jian, Lan; Alexander, Robert; Wicks, Robert; Stevens, Michael; Figueroa-Vinas, Adolfo; Russell, Christopher

    2015-04-01

    Strong narrow-band electromagnetic waves around the proton cyclotron frequency have been found sporadically in the solar wind throughout the inner heliosphere. They are nearly-circularly polarized and propagate close to the magnetic field. Electromagnetic waves near the proton cyclotron frequency can be ion cyclotron waves or magnetosonic waves. They can play an important role in modulating the solar wind ion distribution, and contribute to the heating and acceleration of solar wind. Since the waves are left-hand or right-hand polarized in the spacecraft frame with similar characteristics, they are probably due to Doppler shift of a same type of waves, or there could be a mixture of waves with intrinsically different polarizations. Through the assistance of audification, we have studied the long-lasting low frequency wave events in 2005 using high-cadence magnetic field data from the Wind mission. The Solar Wind Experiment team of the Wind mission has provided the temperature anisotropies for core protons, beam protons, and alpha particles, as well as the beam drift for selected cases. We conduct wave dispersion analysis using these ion moments to examine if these waves can be explained by ion cyclotron anisotropy instability or ion beam instability related to the solar wind inhomogeneities.

  2. Advanced launcher design options for electron cyclotron current drive on ITER based on remote steering

    NARCIS (Netherlands)

    Graswinckel, M. R.; Bongers, W. A.; M.R. de Baar,; van den Berg, M. A.; Denisov, G.; Donne, A. J. H.; Elzendoorn, B. S. Q.; Goede, A. P. H.; Heidinger, R.; Kuzikov, S.; Kruijt, O. G.; Kruizinga, B.; Moro, A.; Poli, E.; Ronden, D. M. S.; Saibene, G.; Thoen, D. J.; Verhoeven, A. G. A.

    2008-01-01

    Electron cyclotron current drive will become the main scheme on ITER for the stabilization of neoclassical tearing modes (NTMs) and the control of sawtooth oscillations. The effectiveness of this scheme forms the basis for the requirements of the ITER Upper Port Launcher. These requirements include

  3. Design and installation of the electron cyclotron wave system for the TCV tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, T.P.; Alberti, S.; Henderson, M.A.; Pochelon, A.; Tran, M.Q. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1996-10-01

    The design of a combined 82.7 GHz and 118 GHz, 4.5 MW, 2.0 s electron cyclotron wave (ECW) system for heating and current drive on TCV is described. Low and high power test results of the RF source, transmission line and launching antenna are presented. (author) 3 figs., 5 refs.

  4. Tomsk Polytechnic University cyclotron as a source for neutron based cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Lisin, V. A. [Cancer Research Institute, 5 Kooperativny St., Tomsk 634050 (Russian Federation); Tomsk Polytechnic University, 30 Lenina av., Tomsk 634050 (Russian Federation); Bogdanov, A. V.; Golovkov, V. M.; Sukhikh, L. G.; Verigin, D. A., E-mail: verigin@tpu.ru [Tomsk Polytechnic University, 30 Lenina av., Tomsk 634050 (Russian Federation); Musabaeva, L. I. [Cancer Research Institute, 5 Kooperativny St., Tomsk 634050 (Russian Federation)

    2014-02-15

    In this paper we present our cyclotron based neutron source with average energy 6.3 MeV generated during the 13.6 MeV deuterons interactions with beryllium target, neutron field dosimetry, and dosimetry of attendant gamma fields. We also present application of our neutron source for cancer treatment.

  5. Fast Ion Induced Shearing of 2D Alfven Eigenmodes Measured by Electron Cyclotron Emission Imaging

    NARCIS (Netherlands)

    Tobias, B. J.; Classen, I.G.J.; Domier, C.W.; Heidbrink, W. W.; N C Luhmann Jr.,; Nazikian, R.; Park, H. K.; Spong, D. A.; VanZeeland, M. A.

    2011-01-01

    Two-dimensional images of electron temperature perturbations are obtained with electron cyclotron emission imaging (ECEI) on the DIII-D tokamak and compared to Alfven eigenmode structures obtained by numerical modeling using both ideal MHD and hybrid MHD-gyrofluid codes. While many features of the o

  6. Simulation on the electronic wave packet cyclotron motion in a Weyl semimetal slab.

    Science.gov (United States)

    Yao, Haibo; Zhu, Mingfeng; Jiang, Liwei; Zheng, Yisong

    2017-04-20

    We perform a numerical simulation on the time evolution of an electronic wave packet in a Weyl semimetal (WSM) slab driven by a magnetic field. We find that the evolution trajectory of the wave packet depends sensitively on its initial spin state. Only with initial spin state identical to that of the Fermi arc state at the surface it localized, does the wave packet evolution demonstrate the characteristic cyclotron orbit of WSM previously predicted from a semiclassical viewpoint. By analyzing the eigen-expansion of the electronic wave packet, we find the chiral Landau levels (LLs) of the WSM slab, as ingredients of the wave packet, to be responsible for establishing the characteristic WSM cyclotron orbit. In contrast, the nonchiral LLs contribute irregular oscillations to the wave packet evolution, going against the formation of a well-defined cyclotron orbit. In addition, the tilted magnetic field does not affect the motion of the electronic wave packet along the Fermi arcs in the momentum space. It does, however, alter the evolution trajectory of the electronic wave packet in real space and spin space. Finally, the energy disalignment of the Weyl nodes results in a 3D cyclotron orbit in real space.

  7. Determining Contents of Five Impurities in Cyclotron- Produced ~(64)Cu Solution by Emission Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    64Cu ( β+=17%, β-=39%, IEC=43%) is an important emerging biomedical radionuclide, which is useful for PET as well as a promising radiotherapy agent for the treatment of cancer. It can be produced on a small biomedical cyclotron utilizing 64Ni(p, n)64Cu nuclear reaction.

  8. Dispersion equations for field-aligned cyclotron waves in axisymmetric magnetospheric plasmas

    Directory of Open Access Journals (Sweden)

    N. I. Grishanov

    2006-03-01

    Full Text Available In this paper, we derive the dispersion equations for field-aligned cyclotron waves in two-dimensional (2-D magnetospheric plasmas with anisotropic temperature. Two magnetic field configurations are considered with dipole and circular magnetic field lines. The main contribution of the trapped particles to the transverse dielectric permittivity is estimated by solving the linearized Vlasov equation for their perturbed distribution functions, accounting for the cyclotron and bounce resonances, neglecting the drift effects, and assuming the weak connection of the left-hand and right-hand polarized waves. Both the bi-Maxwellian and bi-Lorentzian distribution functions are considered to model the ring current ions and electrons in the dipole magnetosphere. A numerical code has been developed to analyze the dispersion characteristics of electromagnetic ion-cyclotron waves in an electron-proton magnetospheric plasma with circular magnetic field lines, assuming that the steady-state distribution function of the energetic protons is bi-Maxwellian. As in the uniform magnetic field case, the growth rate of the proton-cyclotron instability (PCI in the 2-D magnetospheric plasmas is defined by the contribution of the energetic ions/protons to the imaginary part of the transverse permittivity elements. We demonstrate that the PCI growth rate in the 2-D axisymmetric plasmasphere can be significantly smaller than that for the straight magnetic field case with the same macroscopic bulk parameters.

  9. Closure of the single fluid magnetohydrodynamic equations in presence of electron cyclotron current drive

    NARCIS (Netherlands)

    Westerhof, E.; Pratt, J.

    2014-01-01

    In the presence of electron cyclotron current drive (ECCD), the Ohm's law of single fluid magnetohydrodynamics is modified as E + v × B = η(J – J EC). This paper presents a new closure relation for the EC driven current density appearing in this modified Ohm's law. The new relation faithfu

  10. Commissioning of electron cyclotron emission imaging instrument on the DIII-D tokamak and first data

    NARCIS (Netherlands)

    Tobias, B.; Domier, C.W.; Liang, T.; Kong, X.; Yu, L.; Yun, G. S.; Park, H. K.; Classen, I.G.J.; Boom, J. E.; Donne, A. J. H.; Munsat, T.; Nazikian, R.; Van Zeeland, M.; Boivin, R. L.; N C Luhmann Jr.,

    2010-01-01

    A new electron cyclotron emission imaging diagnostic has been commissioned on the DIII-D tokamak. Dual detector arrays provide simultaneous two-dimensional images of T-e fluctuations over radially distinct and reconfigurable regions, each with both vertical and radial zoom capability. A total of 320

  11. Design Study of Superconducting Coil of 230 MeV Superconducting Cyclotron

    Institute of Scientific and Technical Information of China (English)

    WANG; Chuan; YIN; Meng; ZHANG; Su-ping; LI; Ming; CUI; Tao; LIN; Jun; LV; Yin-long; GE; Tao; YIN; Zhi-guo; ZHANG; Tian-jue

    2015-01-01

    The superconducting coil system of CYCIAE-230superconducting proton cyclotron consists of two coil windings,cryostat,GM coolers,and the liquid helium condenser(Fig.1),along with multiple thermometers,pressure gauges,liquid level gauges,load cells,a vacuum pump,a

  12. Distorted cyclotron line profile in Cep X-4 as observed by NuSTAR

    DEFF Research Database (Denmark)

    Fürst, F.; Pottschmidt, K.; Miyasaka, H.;

    2015-01-01

    a powerlaw with a Fermi-Dirac cutoff at high energies. Cep X-4 has a very strong cyclotron resonant scattering feature (CRSF) around 30 keV. A simple absorption-like line with a Gaussian optical depth or a pseudo-Lorentzian profile both fail to describe the shape of the CRSF accurately, leaving significant...

  13. Cyclotron laboratory of the Institute for Nuclear Research and Nuclear Energy

    Science.gov (United States)

    Tonev, D.; Goutev, N.; Georgiev, L. S.

    2016-06-01

    An accelerator laboratory is presently under construction in Sofia at the Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences. The laboratory will use a TR24 type of cyclotron, which provides a possibility to accelerate a proton beam with an energy of 15 to 24 MeV and current of up to 0.4 mA. An accelerator with such parameters allows to produce a large variety of radioisotopes for development of radiopharmaceuticals. The most common radioisotopes that could be produced with such a cyclotron are PET isotopes like: 11C, 13N, 15O, 18F, 124I, 64Cu, 68Ge/68Ga, and SPECT isotopes like: 123I, 111In, 67Ga, 57Co, 99m Tc. Our aim is to use the cyclotron facility for research in the fields of radiopharmacy, radiochemistry, radiobiology, nuclear physics, solid state physics, applied research, new materials and for education in all these fields including nuclear energy. The building of the laboratory will be constructed nearby the Institute for Nuclear Research and Nuclear Energy and the cyclotron together with all the equipment needed will be installed there.

  14. Design study of a 9 MeV compact cyclotron system for PET

    Science.gov (United States)

    Lee, Byeong-No; Shin, Seung-Wook; Song, Hoseung; Kim, Hyun-Wook; Chai, Jong-Seo

    2013-06-01

    A cyclotron is an accelerator which can be applied to both cancer diagnosis and treatment. Among commercially sold cyclotrons, the major energy is used for positron emission tomography (PET) ranges from 10 to 20 MeV. In this research, 9 MeV compact cyclotron for PET was designed. The research was conducted on the response cross section and the yield for the energy distribution to decide the design features. Also, it was determined the specifications on the basis of the fluoro-deoxy-glucose (FDG) maximum dose. The machine, which has a 20 uA beam current, is designed to be installed in small-to-medium-sized hospitals in local cities because of its relatively light weight (6 tons). This compact cyclotron, which provides 9-MeV proton beams, is composed of a azimuthally varying field (AVF) electromagnet, 83-MHz RF systems with a 20 kW amplifier, a panning ion gauge (PIG) type ion-source for negative hydrogen, and a double-stage high-vacuum system. The basic model design was done by using 3-D CAD program, CATIA and all the field calculations were performed using commercial electromagnetic field analysis code, OPERA-3D TOSCA. From this research, we expect a time reduction for FDG production, a decrease of radioactive exposure for workers, and an equipment cost reduction.

  15. Electron cyclotron emission measurements on JET: Michelson interferometer, new absolute calibration, and determination of electron temperature

    NARCIS (Netherlands)

    Schmuck, S.; Fessey, J.; Gerbaud, T.; Alper, B.; Beurskens, M. N. A.; de la Luna, E.; Sirinelli, A.; Zerbini, M.

    2012-01-01

    At the fusion experiment JET, a Michelson interferometer is used to measure the spectrum of the electron cyclotron emission in the spectral range 70-500 GHz. The interferometer is absolutely calibrated using the hot/cold technique and, in consequence, the spatial profile of the plasma electron tempe

  16. Buncher Power Source Monitoring System of 100 MeV Cyclotron

    Institute of Scientific and Technical Information of China (English)

    WEI; Jun-yi; FU; Xiao-liang; GUO; Juan-juan; ZHANG; Yi-wang; CAO; Xue-long; YIN; Zhi-guo; JI; Bin

    2015-01-01

    The 100MeV cyclotron provides 70-100MeV and 200μA proton beam,which can be used in astrophysics,medical,defense,energy and other fields.Buncher system can enhance the beam intensity and expand the scope of application of the accelerator.Buncher system is one part of the

  17. Neutron Beams from Deuteron Breakup at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    McMahan, M.A.; Ahle, L.; Bleuel, D.L.; Bernstein, L.; Braquest, B.R.; Cerny, J.; Heilbronn, L.H.; Jewett, C.C.; Thompson, I.; Wilson, B.

    2007-07-31

    Accelerator-based neutron sources offer many advantages, in particular tunability of the neutron beam in energy and width to match the needs of the application. Using a recently constructed neutron beam line at the 88-Inch Cyclotron at LBNL, tunable high-intensity sources of quasi-monoenergetic and broad spectrum neutrons from deuteron breakup are under development for a variety of applications.

  18. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry. Development of instrumentation, data aquisition software and processing methods

    NARCIS (Netherlands)

    Barbu, I.M.

    2008-01-01

    This thesis describes, the use of a Fourier Transform Ion Cyclotron (FTICR) mass spectrometer in the study of biological samples with, imaging mass spectrometry (MS). To achieve this goal experiments were performed on an in-house modified FTICR-MS instrument (for which special acquisition software w

  19. 3-Dimensional Simulations of Multipacting Effects in RF Cavities of CYCIAE-100 Cyclotron

    Institute of Scientific and Technical Information of China (English)

    WANG; Chuan; JI; Bin; LI; Peng-zhan; YIN; Zhi-guo; LEI; Yu; XING; Jian-sheng; ZHANG; Tian-jue

    2013-01-01

    Multipacting phenomena have been observed in various RF structures of accelerators.The multipacting appearing in high-Q RF cavities of cyclotrons,are the well known examples that how disturbing these phenomenon could be during commissioning.The seed electrons will impact the cavity surface,produce new electrons.Under certain conditions(material and geometry of the RF structure,

  20. Stability of electrostatic ion cyclotron waves in a multi-ion plasma

    Indian Academy of Sciences (India)

    M J Kurian; S Jyothi; S K Leju; Molly Isaac; Chandu Venugopal; G Renuka

    2009-12-01

    We have studied the stability of the electrostatic ion cyclotron wave in a plasma consisting of isotropic hydrogen ions (+) and temperature-anisotropic positively (+) and negatively (−) charged oxygen ions, with the electrons drifting parallel to the magnetic field. Analytical expressions have been derived for the frequency and growth/damping rate of ion cyclotron waves around the first harmonic of both hydrogen and oxygen ion gyrofrequencies. We find that the frequencies and growth/damping rates are dependent on the densities and temperatures of all species of ions. A detailed numerical study, for parameters relevant to comet Halley, shows that the growth rate is dependent on the magnitude of the frequency. The ion cyclotron waves are driven by the electron drift parallel to the magnetic field; the temperature anisotropy of the oxygen ions only slightly enhance the growth rates for small values of temperature anisotropies. A simple explanation, in terms of wave exponentiation times, is offered for the absence of electrostatic ion cyclotron waves in the multi-ion plasma of comet Halley.

  1. Status of the PHOENIX electron cyclotron resonance charge breeder at ISOLDE, CERN.

    Science.gov (United States)

    Barton, Charles; Cederkall, Joakim; Delahaye, Pierre; Kester, Oliver; Lamy, Thierry; Marie-Jeanne, Mélanie

    2008-02-01

    We report here on the last progresses made with the PHOENIX electron cyclotron resonance charge breeder test bench at ISOLDE. Recently, an experiment was performed to test the trapping of (61)Fe daughter nuclides from the decay of (61)Mn nuclides. Preliminary results are given.

  2. LIBO - boosting medical cyclotron facilities for cancer therapy Exhibition LEPFest 2000

    CERN Multimedia

    2000-01-01

    Length : Energy boost : From 62 to 200 MeVAccelerating gradient : 10 MeV/metreAccelerating frequency : 3 GHz Collaboration : CERN, INFN and University of Milan, INFN and University of Naples and TERA foundation Prototype test in 2001 : SC cyclotron Catania

  3. Isotopic anomaly for carbon ions in an electron cyclotron resonance ion source

    NARCIS (Netherlands)

    Drentje, A. G.; Kitagawa, A.; Muramatsu, M.

    2010-01-01

    In many experiments methods were applied to increase the highly charged ion output from an electron cyclotron resonance ion source; the gas-mixing method is still generally being applied. The dominant role of the masses of the ions in the gas-mixture was apparent. Two basically differing mechanisms

  4. Techniques and mechanisms applied in electron cyclotron resonance sources for highly charged ions

    NARCIS (Netherlands)

    Drentje, AG

    2003-01-01

    Electron cyclotron resonance ion sources are delivering beams of highly charged ions for a wide range of applications in many laboratories. For more than two decades, the development of these ion sources has been to a large extent an intuitive and experimental enterprise. Much effort has been spent

  5. An overview of control system for the ITER electron cyclotron system

    NARCIS (Netherlands)

    Purohit, D.; Bigelow, T.; Billava, D.; Bonicelli, T.; Caughman, J.; Darbos, C.; Denisov, G.; Gandini, F.; Gassmann, T.; Henderson, M.; Journeux, J. Y.; Kajiwara, K.; Kobayashi, N.; Nazare, C.; Oda, Y.; Omori, T.; Rao, S. L.; Rasmussen, D.; Ronden, D.; Saibene, G.; Sakamoto, K.; Sartori, F.; Takahashi, K.; Temkin, R.

    2011-01-01

    The ITER electron cyclotron (EC) system having capability of up to 26 MW generated power at 170 GHz is being procured by 5 domestic agencies via 10 procurement arrangements. This implies diverse types of equipment and complex interface management. It also places a challenge on control system archite

  6. Observations of rotation in JET plasmas with electron heating by ion cyclotron resonance heating

    NARCIS (Netherlands)

    Hellsten, T.; Johnson, T. J.; Van Eester, D.; Lerche, E.; Lin, Y.; Mayoral, M. L.; Ongena, J.; Calabro, G.; Crombe, K.; Frigione, D.; Giroud, C.; Lennholm, M.; Mantica, P.; Nave, M. F. F.; Naulin, V.; Sozzi, C.; Studholme, W.; Tala, T.; Versloot, T.

    2012-01-01

    The rotation of L-mode plasmas in the JET tokamak heated by waves in the ion cyclotron range of frequencies (ICRF) damped on electrons, is reported. The plasma in the core is found to rotate in the counter-current direction with a high shear and in the outer part of the plasma with an almost constan

  7. Electron cyclotron heating and current drive in toroidal geometry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kritz, A.H.

    1991-11-01

    The Principal Investigator has continued to work on problems associated both with the deposition and with the emission of electron cyclotron power in toroidal plasmas. We have investigated the use of electron cyclotron resonance heating for bringing compact tokamaks (BPX) to ignition-like parameters. This requires that we continue to refine the modeling capability of the TORCH code linked with the BALDUR 1 {1/2} D transport code. Using this computational tool, we have examined the dependence of ignition on heating and transport employing both theoretical (multi-mode) and empirically based transport models. The work on current drive focused on the suppression of tearing modes near the q = 2 surface and sawteeth near the q = 1 surface. Electron cyclotron current drive in CIT near the q =2 surface was evaluated for a launch scenario where electron cyclotron power was launched near the equatorial plane. The work on suppression of sawteeth has been oriented toward understanding the suppression that has been observed in a number of tokamaks, in particular, in the WT-3 tokamak in Kyoto. To evaluate the changes in current profile (shear) near the q =1 surface, simulations have been carried out using the linked BALDUR-TORCH code. We consider effects on shear resulting both from wave-induced current as well as from changes in conductivity associated with changes in local temperature. Abstracts and a paper relating to this work is included in Appendix A.

  8. Geometric analysis of phase bunching in the central region of cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Miyawaki, Nobumasa, E-mail: miyawaki.nobumasa@jaea.go.jp [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Fukuda, Mitsuhiro [Research Center for Nuclear Physics, Osaka University, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Kurashima, Satoshi; Kashiwagi, Hirotsugu; Okumura, Susumu [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Arakawa, Kazuo [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Gunma University Heavy Ion Medical Center, Gunma University, 3-39-22 Showa-Machi, Maebashi, Gunma 371-8511 (Japan); Kamiya, Tomihiro [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2013-07-01

    An optimum condition for realizing phase bunching in the central region of a cyclotron was quantitatively clarified by a simplified geometric trajectory analysis of charged particles from the first to the second acceleration gap. The phase bunching performance was evaluated for a general case of a cyclotron. The phase difference of incident particles at the second acceleration gap depends on the combination of four parameters: the acceleration harmonic number h, the span angle θ{sub D} of the dee electrode, the span angle θ{sub F} from the first to the second acceleration gap, the ratio R{sub V} of the peak acceleration voltage between the cyclotron and ion source. Optimum values of θ{sub F} for phase bunching were limited by the relationship between h and θ{sub D}, which is 90°/h+θ{sub D}/2≤θ{sub F}≤180°/h+θ{sub D}/2, and sin θ{sub F}>0. The phase difference with respect to the reference particle at the second acceleration gap is minimized for voltage-ratios between two and four for an initial phase difference within 40 RF degrees. Although the slope of the first acceleration gap contributes to the RF phase at which the particles reach the second acceleration gap, phase bunching was not affected. An orbit simulation of the AVF cyclotron at the Japan Atomic Energy Agency verifies the evaluation based on geometric analysis.

  9. Alfvenic behavior of alpha particle driven ion cyclotron emission in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Cauffman, S.; Majeski, R. [Princeton Plasma Physics Lab., NJ (United States); McClements, K.G. [UKAEA Government Division, Oxfordshire (United Kingdom). Euratom/UKAEA Fusion Association] [and others

    1995-07-01

    Ion cyclotron emission (ICE) has been observed during D-T discharges in the Tokamak Fusion Test Reactor (TFTR), using rf probes located near the top and bottom of the vacuum vessel. Harmonics of the alpha cyclotron frequency ({Omega}{sub {alpha}}) evaluated at the outer midplane plasma edge are observed at the onset of the beam injection phase of TFTR supershots, and persist for approximately 100-250 ms. These results are in contrast with observations of ICE in JET, in which harmonics of {Omega}{sub {alpha}} evolve with the alpha population in the plasma edge. Such differences are believed to be due to the fact that newly-born fusion alpha particles are super-Alfvenic near the edge of JET plasmas, while they are sub-Alfvenic near the edge of TFTR supershot plasmas. In TFTR discharges with edge densities such that newly-born alpha particles are super-Alfvenic, alpha cyclotron harmonics are observed to persist. These results are in qualitative agreement with numerical calculations of growth rates due to the magnetoacoustic cyclotron instability.

  10. On-line Scheduling Algorithm for Penicillin Fed-batch Fermentation

    Institute of Scientific and Technical Information of China (English)

    XUE Yao-feng; YUAN Jing-qi

    2005-01-01

    An on-line scheduling algorithm to maximize gross profit of penicillin fed-batch fermentation is proposed. According to the on-line classification method, fed-batch fermentation batches are classified into three categories. Using the scheduling strategy, the optimal termination sequence of batches is obtained. Pseudo on-line simulations for testing the proposed algorithm with the data from industrial scale penicillin fermentation are carried out.

  11. On-line determination of anions in pulp mills by capillary electrophoresis (CE); Tehdasoloissa tapahtuva anionien kapillaarielektroforeettinen on-line maeaeritys ja sen hyoedyntaeminen prosessivalvonnassa - MPKY 02

    Energy Technology Data Exchange (ETDEWEB)

    Kokkonen, R.; Holmberg, M.; Vainikka, V. [Finnish Pulp and Paper Research Institute, Espoo (Finland)

    1998-12-31

    The aim of the study was to set-up a process control system for on-line measurement of certain anions. Typical anions which forms precipitates in pulp and paper mills are oxalate, carbonate and sulphate. Thus it is important to develop a continuous process analyzing system to control concentration levels of this anions. For the preliminary tests of continuous determinations of chloride and sulphate anions in tap water a simple on-line system was build in KCL (The Finnish Pulp and Paper Research Institute) and connected to a capillary electroforesis apparatus. In the preliminary tests a chromate buffer (ph = 7.6) was used. Separation of chloride and sulphate was excellent but the stability of buffer was not good enough and it was usable only for few hours. After experimental studies VTT developed a stable capillary electrophoresis method based on mixed amine buffer and this was selected for an on-line method for determination of anions in process waters of the pulp and paper industry. In the preliminary on-line test (r = 20) repeatabilities of migration times of sulphate and chloride with the chromate buffer were < 5 % (RSD) and peak heights < 15 % (RSD). With the mixed amine buffer repeatabilities were better. The preliminary tests showed that it is possible to connect a capillary electrophoresis system to on-line measurements. For the moment no commercial on-line CE apparatus is available. (orig.)

  12. An On-line Assessment System for English-Chinese Translation

    Institute of Scientific and Technical Information of China (English)

    TIAN Yan; LU Ru-zhan; DUAN Jian-yong

    2007-01-01

    On-line assessment of English-Chinese translation is a challenging task as it involves natural language processing. YanFa, an on-line assessment system for English-Chinese translation, is a pilot research project into scoring student's translation on-line. Based on the theory of translation equivalence, an algorithm called "conceptual similarity matching" was developed. YanFa can assess students' translation on-line timely, generate test papers automatically, offer standard versions of translation, and the scores of each sentence to students. The evaluation proves that YanFa is practical compared with the scores given by experts.

  13. On-Line Booking Policies and Competitive Analysis of Medical Examination in Hospital

    Directory of Open Access Journals (Sweden)

    Li Luo

    2014-01-01

    Full Text Available From the on-line point, we consider the hospital’s medical examination appointment problem with hierarchical machines. This approach eliminates the need for both demand forecasts and a risk-neutrality assumption. Due to different unit revenue, uncertain demand, and arrival of patients, we design on-line booking policies for two kinds of different situations from the perspective of on-line policy and competitive analysis. After that, we prove the optimal competitive ratios. Through numerical examples, we compare advantages and disadvantages between on-line policies and traditional policies, finding that there is different superiority for these two policies under different arrival sequences.

  14. Radiologic assessment of a self-shield with boron-containing water for a compact medical cyclotron.

    Science.gov (United States)

    Horitsugi, Genki; Fujibuchi, Toshioh; Yamaguchi, Ichiro; Eto, Akihisa; Iwamoto, Yasuo; Hashimoto, Hiromi; Hamada, Seiki; Obara, Satoshi; Watanabe, Hiroshi; Hatazawa, Jun

    2012-07-01

    The cyclotron at our hospital has a self-shield of boron-containing water. The amount of induced radioactivity in the boron-containing water shield of a compact medical cyclotron has not yet been reported. In this study, we measured the photon and neutron dose rates outside the self-shield during cyclotron operation. We estimated the induced radioactivities of the boron-containing water used for the self-shield and then measured them. We estimated the activation of concrete outside the self-shield in the cyclotron laboratory. The thermal neutron flux during cyclotron operation was estimated to be 4.72 × 10(2) cm(-2) s(-1), and the activation of concrete in a cyclotron laboratory was about three orders of magnitude lower than the clearance level of RS-G-1.7 (IAEA). The activity concentration of the boron-containing water did not exceed the concentration limit for radioactive isotopes in drainage in Japan and the exemption level for Basic Safety Standards. Consequently, the boron-containing water is treatable as non-radioactive waste. Neutrons were effectively shielded by the self-shield during cyclotron operation.

  15. Production of high intensity {sup 48}Ca for the 88-Inch Cyclotron and other updates

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, J. Y.; Hodgkinson, A.; Lyneis, C. M., E-mail: jybenitez@lbl.gov; Strohmeier, M.; Thullier, T.; Todd, D.; Xie, D. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Franzen, K. Y. [Mevion Medical Systems, 300 Foster St., Littleton, Massachusetts 01460 (United States)

    2014-02-15

    Recently the Versatile ECR for NUclear Science (VENUS) ion source was engaged in a 60-day long campaign to deliver high intensity {sup 48}Ca{sup 11+} beam to the 88-Inch Cyclotron. As the first long term use of VENUS for multi-week heavy-element research, new methods were developed to maximize oven to target efficiency. First, the tuning parameters of VENUS for injection into the cyclotron proved to be very different than those used to tune VENUS for maximum beam output of the desired charge state immediately following its bending magnet. Second, helium with no oxygen support gas was used to maximize the efficiency. The performance of VENUS and its low temperature oven used to produce the stable requested 75 eμA of {sup 48}Ca{sup 11+} beam current was impressive. The consumption of {sup 48}Ca in VENUS using the low temperature oven was checked roughly weekly, and was found to be on average 0.27 mg/h with an ionization efficiency into the 11+ charge state of 5.0%. No degradation in performance was noted over time. In addition, with the successful operation of VENUS the 88-Inch cyclotron was able to extract a record 2 pμA of {sup 48}Ca{sup 11+}, with a VENUS output beam current of 219 eμA. The paper describes the characteristics of the VENUS tune used for maximum transport efficiency into the cyclotron as well as ongoing efforts to improve the transport efficiency from VENUS into the cyclotron. In addition, we briefly present details regarding the recent successful repair of the cryostat vacuum system.

  16. Production of high intensity 48Ca for the 88-Inch Cyclotron and other updates

    Science.gov (United States)

    Benitez, J. Y.; Franzen, K. Y.; Hodgkinson, A.; Lyneis, C. M.; Strohmeier, M.; Thullier, T.; Todd, D.; Xie, D.

    2014-02-01

    Recently the Versatile ECR for NUclear Science (VENUS) ion source was engaged in a 60-day long campaign to deliver high intensity 48Ca11+ beam to the 88-Inch Cyclotron. As the first long term use of VENUS for multi-week heavy-element research, new methods were developed to maximize oven to target efficiency. First, the tuning parameters of VENUS for injection into the cyclotron proved to be very different than those used to tune VENUS for maximum beam output of the desired charge state immediately following its bending magnet. Second, helium with no oxygen support gas was used to maximize the efficiency. The performance of VENUS and its low temperature oven used to produce the stable requested 75 eμA of 48Ca11+ beam current was impressive. The consumption of 48Ca in VENUS using the low temperature oven was checked roughly weekly, and was found to be on average 0.27 mg/h with an ionization efficiency into the 11+ charge state of 5.0%. No degradation in performance was noted over time. In addition, with the successful operation of VENUS the 88-Inch cyclotron was able to extract a record 2 pμA of 48Ca11+, with a VENUS output beam current of 219 eμA. The paper describes the characteristics of the VENUS tune used for maximum transport efficiency into the cyclotron as well as ongoing efforts to improve the transport efficiency from VENUS into the cyclotron. In addition, we briefly present details regarding the recent successful repair of the cryostat vacuum system.

  17. Discovery of Cyclotron Resonance Features in the Soft Gamma Repeater SGR 1806-20

    Science.gov (United States)

    Ibrahim, Alaa I.; Safi-Harb, Samar; Swank, Jean H.; Parke, William; Zane, Silvia; Turolla, Roberto

    2002-01-01

    We report evidence of cyclotron resonance features from the Soft Gamma Repeater SGR 1806-20 in outburst, detected with the Rossi X-ray Timing Explorer in the spectrum of a long, complex precursor that preceded a strong burst. The features consist of a narrow 5.0 keV absorption line with modulation near its second and third harmonics (at 11.2 keV and 17.5 keV respectively). The line features are transient and are detected in the harder part of the precursor. The 5.0 keV feature is strong, with an equivalent width of approx. 500 eV and a narrow width of less than 0.4 keV. Interpreting the features as electron cyclotron lines in the context of accretion models leads to a large mass-radius ratio (M/R greater than 0.3 solar mass/km) that is inconsistent with neutron stars or that requires a low (5-7) x 10(exp 11) G magnetic field that is unlikely for SGRs. The line widths are also narrow compared with those of electron cyclotron resonances observed so far in X-ray pulsars. In the magnetar picture, the features are plausibly explained as ion cyclotron resonances in an ultra-strong magnetic field that have recently been predicted from magnetar candidates. In this view, the 5.0 keV feature is consistent with a proton cyclotron fundamental whose energy and width are close to model predictions. The line energy would correspond to a surface magnetic field of 1.0 x 10(exp 15) G for SGR 1806-20, in good agreement with that inferred from the spin-down measure in the source.

  18. A comprehensive analysis of ion cyclotron waves in the equatorial magnetosphere of Saturn

    Science.gov (United States)

    Meeks, Zachary; Simon, Sven; Kabanovic, Slawa

    2016-09-01

    We present a comprehensive analysis of ion cyclotron waves in the equatorial magnetosphere of Saturn, considering all magnetic field data collected during the Cassini era (totaling to over 4 years of data from the equatorial plane). This dataset includes eight targeted flybys of Enceladus, three targeted flybys of Dione, and three targeted flybys of Rhea. Because all remaining orbits of Cassini are high-inclination, our study provides the complete map of ion cyclotron waves in Saturn's equatorial magnetosphere during the Cassini era. We provide catalogs of the radial and longitudinal dependencies of the occurrence rate and amplitude of the ion cyclotron fundamental and first harmonic wave modes. The fundamental wave mode is omnipresent between the orbits of Enceladus and Dione and evenly distributed across all Local Times. The occurrence rate of the fundamental mode displays a Fermi-Dirac-like profile with respect to radial distance from Saturn. Detection of the first harmonic mode is a rare event occurring in only 0.49% of measurements taken and always in conjunction with the fundamental mode. We also search for a dependency of the ion cyclotron wave field on the orbital positions of the icy moons Enceladus, Dione, and Rhea. On magnetospheric length scales, the wave field is independent of the moons' orbital positions. For Enceladus, we analyze wave amplitude profiles of seven close flybys (E9, E12, E13, E14, E17, E18, and E19), which occurred during the studied trajectory segments, to look for any local effects of Enceladan plume variability on the wave field. We find that even in the close vicinity of Enceladus, the wave amplitudes display no discernible dependency on Enceladus' angular distance to its orbital apocenter. Thus, the correlation between plume activity and angular distance to apocenter proposed by Hedman et al. (2013) does not leave a clearly distinguishable imprint in the ion cyclotron wave field.

  19. General Electric PETtrace cyclotron as a neutron source for boron neutron capture therapy

    Science.gov (United States)

    Bosko, Andrey

    This research investigates the use of a PETtrace cyclotron produced by General Electric (GE) as a neutron source for boron neutron capture therapy (BNCT). The GE PETtrace was chosen for this investigation because this type of cyclotron is popular among nuclear pharmacies and clinics in many countries; it is compact and reliable; it produces protons with energies high enough to produce neutrons with appropriate energy and fluence rate for BNCT and it does not require significant changes in design to provide neutrons. In particular, the standard PETtrace 18O target is considered. The cyclotron efficiency may be significantly increased if unused neutrons produced during radioisotopes production could be utilized for other medical modalities such as BNCT at the same time. The resulting dose from the radiation emitted from the target is evaluated using the Monte Carlo radiation transport code MCNP at several depths in a brain phantom for different scattering geometries. Four different moderating materials of various thicknesses were considered: light water, carbon, heavy water, arid Fluental(TM). The fluence rate tally was used to calculate photon and neutron dose, by applying fluence rate-to-dose conversion factors. Fifteen different geometries were considered and a 30-cm thick heavy water moderator was chosen as the most suitable for BNCT with the GE PETtrace cyclotron. According to the Brookhaven Medical Research Reactor (BMRR) protocol, the maximum dose to the normal brain is set to 12.5 RBEGy, which for the conditions of using a heavy water moderator, assuming a 60 muA beam current, would be reached with a treatment time of 258 min. Results showed that using a PETtrace cyclotron in this configuration provides a therapeutic ratio of about 2.4 for depths up to 4 cm inside a brain phantom. Further increase of beam current proposed by GE should significantly improve the beam quality or the treatment time and allow treating tumors at greater depths.

  20. Cyclotron resonance in InAs/AlSb quantum wells in magnetic fields up to 45 T

    Energy Technology Data Exchange (ETDEWEB)

    Spirin, K. E., E-mail: spirink@ipmras.ru; Krishtopenko, S. S. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Sadofyev, Yu. G. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Drachenko, O. [Laboratoire National des Champs Magn’etiques Intenses (France); Helm, M. [Forschungszentrum Dresden–Rossendorf, Dresden High-Magnetic-Field Laboratory and Institute of Ion-Beam Physics and Materials Research (Germany); Teppe, F.; Knap, W. [GIS-TERALAB Universite Montpellier II, Laboratoire Charles Coulomb UMR CNRS 5221 (L2C) (France); Gavrilenko, V. I. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2015-12-15

    Electron cyclotron resonance in InAs/AlSb heterostructures with quantum wells of various widths in pulsed magnetic fields up to 45 T are investigated. Our experimental cyclotron energies are in satisfactory agreement with the results of theoretical calculations performed using the eight-band kp Hamiltonian. The shift of the cyclotron resonance (CR) line, which corresponds to the transition from the lowest Landau level to the low magnetic-field region, is found upon varying the electron concentration due to the negative persistent photoconductivity effect. It is shown that the observed shift of the CR lines is associated with the finite width of the density of states at the Landau levels.

  1. Radiologic assessment of a self-shield with boron-containing water for a compact medical cyclotron

    OpenAIRE

    Horitsugi, Genki; Fujibuchi, Toshioh; Yamaguchi, Ichiro; Eto, Akihisa; Iwamoto, Yasuo; Hashimoto, Hiromi; Hamada, Seiki; Obara, Satoshi; Watanabe, Hiroshi; Hatazawa, Jun

    2012-01-01

    The cyclotron at our hospital has a self-shield of boron-containing water. The amount of induced radioactivity in the boron-containing water shield of a compact medical cyclotron has not yet been reported. In this study, we measured the photon and neutron dose rates outside the self-shield during cyclotron operation. We estimated the induced radioactivities of the boron-containing water used for the self-shield and then measured them. We estimated the activation of concrete outside the self-s...

  2. Analysis and suppression of RF radiation from the PSI 590 MeV cyclotron Flat Top Cavity

    Science.gov (United States)

    Pogue, N. J.; Stingelin, L.; Adelmann, A.

    2016-08-01

    The Flat Top Cavity, located in the PSI HIPA Ring Cyclotron leaks RF power of several kilo Watts into the cyclotron's vacuum space causing several complications. A detailed electromagnetic model was created and simulations performed to analyze the mechanisms by which power is leaking out of the Flat Top Cavity. The tolerances needed to limit the leaked power in future iterations of the Flat Top cavity are reported. Comparison of the model to measurements are described as well as two potential methods to limit power leakage. These studies will have direct impact on future RF cavity designs for cyclotrons as power levels increase and higher RF fields are required.

  3. Two-stream cyclotron radiative instabilities due to the marginally mirror-trapped fraction for fustion alphas in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Arunasalam, V.

    1995-07-01

    It is shown here that the marginally mirror-trapped fraction of the newly-born fusion alpha particles in the deuterium-tritium (DT) reaction dominated tokamak plasmas can induce a two-stream cyclotron radiative instability for the fast Alfven waves propagating near the harmonics of the alpha particle cyclotron frequency {omega}{sub c{alpha}}. This can explain both the experimentally observed time behavior and the spatially localized origin of the fusion product ion cyclotron emission (ICE) in TFTR at frequencies {omega} {approx} m{omega}{sub c{alpha}}.

  4. High School Open On-Line Courses (HOOC): A Case Study from Italy

    Science.gov (United States)

    Canessa, Enrique; Pisani, Armando

    2013-01-01

    The first implementation of complete high school, open on-line courses (HOOC) aiming to support the training and basic scientific knowledge of young students from the Liceo Ginnasio Dante Alighieri in Gorizia, Italy, is discussed. Using the open source and automated recording system openEyA, HOOC give a student the opportunity to watch on-line, at…

  5. On-Line Multichannel Raman Spectroscopic Detection System For Capillary Zone Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An on-line multichannel Raman spectroscopic detection system for capillary electrophoresis was established by using an Ar+ laser and a cryogenically cooled ICCD. Resonant excitation Raman spectra of methyl red and methyl orange were employed to test the system. The result shows that it could yield on-line electrophoretogram and time series of Raman spectra.

  6. Semi-on-line analysis for fast and precise monitoring of bioreaction processes

    DEFF Research Database (Denmark)

    Christensen, L.H.; Marcher, J.; Schulze, Ulrik;

    1996-01-01

    Monitoring of substrates and products during fermentation processes can be achieved either by on-line, in situ sensors or by semi-on-line analysis consisting of an automatic sampling step followed by an ex situ analysis of the retrieved sample. The potential risk of introducing time delays...

  7. A novel, optical, on-line bacteria sensor for monitoring drinking water quality

    DEFF Research Database (Denmark)

    Højris, Bo; Christensen, Sarah Christine Boesgaard; Albrechtsen, Hans-Jørgen;

    2016-01-01

    Today, microbial drinking water quality is monitored through either time-consuming laboratory methods or indirect on-line measurements. Results are thus either delayed or insufficient to support proactive action. A novel, optical, on-line bacteria sensor with a 10-minute time resolution has been...... conditions such as pollution events in drinking water....

  8. Analyze On-line Star Economy Basing on Models of Entrepreneurship

    Institute of Scientific and Technical Information of China (English)

    胡志豪

    2016-01-01

    The outstanding performance of the On-line Star Economy is bound up with social media and promotion by fans, stimulating a new round of consumption upgrading and capital tendency. There is no denying that the On-line Star Economy may be the fortuitous outcome of the times. But the fact remains it can be analyzed rationally using Models of Entrepreneurship.

  9. On-line monitoring and control of animal-cell cultures.

    NARCIS (Netherlands)

    Pol, van der J.J.

    1996-01-01

    On-line analysis and control of biotechnological processes is still the stepchild in industry. In general, only parameters as dissolved-oxygen concentration, pH and temperature are controlled on-line. Important parameters as substrate and inhibitor concentrations are only measured offline. Controlli

  10. Enhancing On-Line Teaching with Verbal Immediacy through Self-Determination Theory

    Science.gov (United States)

    Furlich, Stephen A.

    2013-01-01

    This paper explores the use of instructor verbal immediacy behaviors for on-line classes. Specifically, it demonstrates how instructor verbal immediacy behaviors found in face-to-face classes can also be displayed for on-line classes. It is argued that self-determination theory describes identification of the student as an important role in the…

  11. A New Method of On-line Grid Impedance Estimation for PV Inverter

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Asiminoaei, Lucian; Blaabjerg, Frede

    2004-01-01

    for on-line measuring the grid impedance is presented. The presented method requires no extra hardware being accommodated by typical PV inverters, sensors and CPU, to provide a fast and low cost approach of on-line impedance measurement. By injecting a non-characteristic harmonic current and measuring...

  12. The Anatomy of Program Design for an On-Line Business Management Course

    Science.gov (United States)

    Barger, Bonita

    2008-01-01

    How does one design an on-line course to bridge theory and practice? How can the feedback of on-going stakeholder (student and administration) be incorporated into the design process to enhance quality? This paper presents the theoretical underpinning of designing an on-line management course recognized as best practice for a "well organized…

  13. Alternative medicine - pain relief

    Science.gov (United States)

    Alternative medicine refers to treatments that are used instead of conventional (standard) ones. If you use an alternative ... with conventional medicine or therapy, it is considered complementary therapy. There are many forms of alternative medicine. Acupuncture ...

  14. Comparative study of ion cyclotron waves at Mars, Venus and Earth

    Science.gov (United States)

    Wei, H. Y.; Russell, C. T.; Zhang, T. L.; Blanco-Cano, X.

    2011-08-01

    Ion cyclotron waves are generated in the solar wind when it picks up freshly ionized planetary exospheric ions. These waves grow from the free energy of the highly anisotropic distribution of fresh pickup ions, and are observed in the spacecraft frame with left-handed polarization and a wave frequency near the ion's gyrofrequency. At Mars and Venus and in the Earth's polar cusp, the solar wind directly interacts with the planetary exospheres. Ion cyclotron waves with many similar properties are observed in these diverse plasma environments. The ion cyclotron waves at Mars indicate its hydrogen exosphere to be extensive and asymmetric in the direction of the interplanetary electric field. The production of fast neutrals plays an important role in forming an extended exosphere in the shape and size observed. At Venus, the region of exospheric proton cyclotron wave production may be restricted to the magnetosheath. The waves observed in the solar wind at Venus appear to be largely produced by the solar-wind-Venus interaction, with some waves at higher frequencies formed near the Sun and carried outward by the solar wind to Venus. These waves have some similarity to the expected properties of exospherically produced proton pickup waves but are characterized by magnetic connection to the bow shock or by a lack of correlation with local solar wind properties respectively. Any confusion of solar derived waves with exospherically derived ion pickup waves is not an issue at Mars because the solar-produced waves are generally at much higher frequencies than the local pickup waves and the solar waves should be mostly absorbed when convected to Mars distance as the proton cyclotron frequency in the plasma frame approaches the frequency of the solar-produced waves. In the Earth's polar cusp, the wave properties of ion cyclotron waves are quite variable. Spatial gradients in the magnetic field may cause this variation as the background field changes between the regions in which

  15. Observation of increased ion cyclotron resonance signal duration through electric field perturbations.

    Science.gov (United States)

    Kaiser, Nathan K; Bruce, James E

    2005-09-15

    Ion motion in Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) is complex and the subject of ongoing theoretical and experimental studies. Two predominant pathways for the loss of ICR signals are thought to include damping of cyclotron motion, in which ions lose kinetic energy and radially damp toward the center of the ICR cell, and dephasing of ion coherence, in which ions of like cyclotron frequency become distributed out of phase at similar cyclotron radii. Both mechanisms result in the loss of induced ion image current in FTICR-MS measurements and are normally inseparable during time-domain signal analysis. For conventional ICR measurements which take advantage of ion ensembles, maximization of the ion population size and density can produce the desired effect of increasing phase coherence of ions during cyclotron motion. However, this approach also presents the risk of coalescence of ion packets of similar frequencies. In general, ICR researchers in the past have lacked the tools necessary to distinguish or independently control dephasing and damping mechanisms for ICR signal loss. Nonetheless, the ability to impart greater phase coherence of ions in ICR measurements will allow significant advances in FTICR-MS research by improving the current understanding of ICR signal loss contributions of dephasing and damping of ion ensembles, increasing overall time-domain signal length, and possibly, resulting in more routine ultrahigh resolution measurements. The results presented here demonstrate the ability to employ a high density electron beam to perturb electric fields within the ICR cell during detection of cyclotron motion, in an approach we call electron-promoted ion coherence (EPIC). As such, EPIC reduces ICR signal degradation through loss of phase coherence, and much longer time-domain signals can be obtained. Our results demonstrate that time-domain signals can be extended by more than a factor of 4 with the implementation of EPIC, as

  16. The NASA Astrophysics Data System Free Access to the Astronomical Literature On-Line and through Email

    CERN Document Server

    Eichhorn, G; Grant, C S; Kurtz, M J; Murray, S S

    2001-01-01

    The Astrophysics Data System (ADS) provides access to the astronomical literature through the World Wide Web. It is a NASA funded project and access to all the ADS services is free to everybody world-wide.The ADS Abstract Service allows the searching of four databases with abstracts in Astronomy, Instrumentation, Physics/Geophysics, and the LANL Preprints with a total of over 2.2 million references. The system also provides access to reference and citation information, links to on-line data, electronic journal articles, and other on-line information. The ADS Article Service contains the articles for most of the astronomical literature back to volume 1. It contains the scanned pages of all the major journals (Astrophysical Journal, Astronomical Journal, Astronomy & Astrophysics, Monthly Notices of the Royal Astronomical Society, and Solar Physics), as well as most smaller journals back to volume 1. The ADS can be accessed through any web browser without signup or login. Alternatively an email interface is ...

  17. Applications of ion cyclotron-resonance to stable isotope separation; Les applications de la resonance cyclotron ionique a la separation des isotopes stables

    Energy Technology Data Exchange (ETDEWEB)

    Louvet, P.; Metayer, L. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. des Procedes d`Enrichissement

    1994-12-31

    The principles and the technological basic concepts of the ion cyclotron-resonance process applied to the separation of metallic isotopes which mass ranges from 40 to 200 for medical and nuclear applications, are reviewed. The CEA (France) has developed a prototype plant, ERIC; first results showing high separation factors allow to consider higher production in the future. A modular code has been developed (RICAN) in order to assess the technic-economical feasibility of the process for various isotopes; examples of calculated results (costs and production) for calcium 48 and gadolinium 157 production are presented. 4 figs., 1 tab., 4 refs.

  18. Isotopic separation through ion cyclotron-resonance: results from the ERIC experiment; La separation isotopique par resonance cyclotron ionique: resultats obtenus avec l`experience ERIC

    Energy Technology Data Exchange (ETDEWEB)

    Compant la Fontaine, A.; Louvet, P. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. des Procedes d`Enrichissement

    1994-12-31

    Stable isotope separation by the means of ion cyclotron-resonance is studied at CEA since 1981. Results from the ERIC experiments are of two types: parameter measurements which help characterizing the plasma and optimizing the process, and isotopic separation results. For example, the selective feature of isotope heating was verified in the cases of zinc and calcium using an electrostatic analyzer. The separation factors of various elements (calcium, zinc, barium, chromium...) are depending on the mass relative difference of the isotopes to be separated, difference which must be large compared to the magnetic field inhomogeneities and the Doppler broadening. 2 figs., 1 tab., 3 refs.

  19. FEDIX on-line information service: Design, develop, test, and implement an on-line research and education information service. Annual status report, September 1992--August 1993

    Energy Technology Data Exchange (ETDEWEB)

    Rodman, J.A.

    1993-08-01

    Federal Information Exchange, Inc. (FIE) is a diversified information services company that is recognized as the major electronic link between the higher education community and the Federal government in the field of research administration. FIE provides a range of information related services to the government, academic and private sectors, including database management, software development and technical support. FEDIX is the on-line information service designed, developed and implemented by FIE to accomplish the following objectives: (1). Broaden the participation of the education community in Federal research and education programs by providing free and unrestricted on-line access to information from all participating Federal agencies; and (2). Provide the education community with on-line access to a single keyword-searchable system for research and educational funding opportunities at the participating Federal agencies.

  20. On-line coupling of macroporous resin column chromatography with direct analysis in real time mass spectrometry utilizing a surface flowing mode sample holder.

    Science.gov (United States)

    Zeng, Shanshan; Wang, Lu; Chen, Teng; Qu, Haibin

    2014-02-06

    A surface flowing mode sample holder was designed as an alternative sampling strategy for direct analysis in real time mass spectrometry (DART-MS). With the sample holder, the on-line coupling of macroporous resin column chromatography with DART-MS was explored and the new system was employed to monitor the column chromatography elution process of Panax notoginseng. The effluent from macroporous resin column was first diluted and mixed with a derivatization reagent on-line, and the mixture was then directly transferred into the ionization region of DART-MS by the sample holder. Notoginsenosides were methylated and ionized in a metastable helium gas stream, and was introduced into MS for detection. The on-line system showed reasonable repeatability with a relative standard deviation of 12.3% for the peak area. Three notoginsenosides, i.e. notoginsenoside R1, ginsenoside Rb1 and ginsenoside Rg1, were simultaneously determined during the eluting process. The alteration of the chemical composition in the effluent was accurately identified in 9 min, agreeing well with the off-line analysis. The presented technique is more convenient compared to the traditional UPLC method. These results suggest that the surface flowing mode DART-MS has a good potential for the on-line process monitoring in the pharmaceutical industry.

  1. On the application of electron cyclotron emission imaging to the validation of theoretical models of magnetohydrodynamic activity

    NARCIS (Netherlands)

    Tobias, B. J.; Boivin, R. L.; Boom, J. E.; Classen, I.G.J.; Domier, C.W.; Donne, A. J. H.; Heidbrink, W. W.; N C Luhmann Jr.,; Munsat, T.; Muscatello, C. M.; Nazikian, R.; Park, H. K.; Spong, D. A.; Turnbull, A. D.; VanZeeland, M. A.; Yun, G. S.

    2011-01-01

    Two-dimensional (2D) imaging of electron temperature perturbations provides a powerful constraint for validating theoretical models describing magnetohydrodynamic plasma behavior. In observation of Alfven wave induced temperature fluctuations, electron cyclotron emission imaging provides unambiguous

  2. Cyclotron lines in X-ray pulsars as a probe of relativistic plasmas in superstrong magnetic fields

    CERN Document Server

    Dal Fiume, D; Masetti, N; Orlandini, M; Palazzi, E; Del Sordo, S; Santangelo, A; Segreto, A; Oosterbroek, T; Parmar, A N; Frontera, Filippo; Masetti, Nicola; Orlandini, Mauro; Palazzi, Eliana; Sordo, Stefano Del; Santangelo, Andrea; Segreto, Alberto; Oosterbroek, Tim; Parmar, Arvind N.

    2000-01-01

    The systematic search for the presence of cyclotron lines in the spectra ofaccreting X-ray pulsars is being carried on with the BeppoSAX satellite sincethe beginning of the mission. These highly successful observations allowed thedetection of cyclotron lines in many of the accreting X-ray pulsars observed.Some correlations between the different measured parameters were found. Wepresent these correlations and discuss them in the framework of the currenttheoretical scenario for the X-ray emission from these sources.

  3. Observation of quasi-periodic frequency sweeping in electron cyclotron emission of nonequilibrium mirror-confined plasma

    CERN Document Server

    Viktorov, M E; Mansfeld, D A; Golubev, S V

    2016-01-01

    Chirping frequency patterns have been observed in the electron cyclotron emission from strongly nonequilibrium plasma confined in a table-top mirror magnetic trap. Such patterns are typical for the formation of nonlinear phase space structures in a proximity of the wave-particle resonances of a kinetically unstable plasma, also known as the "holes and clumps" mechanism. Our data provides the first experimental evidence for acting of this mechanism in the electron cyclotron frequency domain.

  4. Ion-Cyclotron Instability in Current-Carrying Lorentzian (Kappa) and Maxwellian Plasmas with Anisotropic Temperatures: A Comparative Study

    Science.gov (United States)

    2011-09-26

    in the solar wind and in many space plasmas often exhibit non - Maxwellian suprathermal tails that decrease as a power-law of the velocity.1 Such...AFRL-RV-PS- AFRL-RV-PS- TR-2011-0164 TR-2011-0164 ION-CYCLOTRON INSTABILITY IN CURRENT- CARRYING LORENTZIAN (KAPPA) AND MAXWELLIAN PLASMAS...1 Oct 2007 – 9 Sep 2011 4. TITLE AND SUBTITLE Ion-Cyclotron Instability in Current-Carrying Lorentzian (Kappa) and Maxwellian Plasmas 5a. CONTRACT

  5. Initial experience with an 11 MeV self-shielded medical cyclotron on operation and radiation safety

    Directory of Open Access Journals (Sweden)

    Pant G

    2007-01-01

    Full Text Available A self-shielded medical cyclotron (11 MeV was commissioned at our center, to produce positron emitters, namely, 18 F, 15 O, 13 N and 11 C for positron emission tomography (PET imaging. Presently the cyclotron has been exclusively used for the production of 18 F - for 18 F-FDG imaging. The operational parameters which influence the yield of 18 F - production were monitored. The radiation levels in the cyclotron and radiochemistry laboratory were also monitored to assess the radiation safety status in the facility. The target material, 18 O water, is bombarded with proton beam from the cyclotron to produce 18 F - ion that is used for the synthesis of 18 F-FDG. The operational parameters which influence the yield of 18 F - were observed during 292 production runs out of a total of more than 400 runs. The radiation dose levels were also measured in the facility at various locations during cyclotron production runs and in the radiochemistry laboratory during 18 F-FDG syntheses. It was observed that rinsing the target after delivery increased the number of production runs in a given target, as well as resulted in a better correlation between the duration of bombardment and the end of bombardment 18 F - activity with absolutely clean target after being rebuilt. The radiation levels in the cyclotron and radiochemistry laboratory were observed to be well within prescribed limits with safe work practice.

  6. Design of the shielding wall of a cyclotron room and the activation interpretation using the Monte Carlo simulation

    Science.gov (United States)

    Jang, D. G.; Kim, J. M.; Kim, J. H.

    2017-01-01

    Medical cyclotron is mainly a facility used for producing radiopharmaceutical products, which secondarily generate high energy radiation when producing a radiopharmaceutical product. In this study, the intention is that the reductions in spatial dose rate for the radiation generated when cyclotron is operated and the absorbed dose rate, according to the width of shielding wall, will be analyzed. The simulation planned targetry and protons of 16.5 MeV, 60μA through a Monte Carlo simulation, and as a result of the simulation, it has been found through an analysis that a concrete shielding wall of 200 cm is needed, according to the absorbed dose rate of the shielding wall thickness of cyclotron, and the concrete gives an external exposure level of 1 μSv/hr after 19 years of cyclotron operation as it is activated by the nuclear reaction of cyclotron. When taking into account the mechanical life span of cyclotron, it is deemed necessary to develop additional shielding and a low activation material.

  7. MM-wave cyclotron auto-resonance maser for plasma heating

    Energy Technology Data Exchange (ETDEWEB)

    Ceccuzzi, S.; Ravera, G. L.; Tuccillo, A. A. [Associazione Euratom-ENEA sulla Fusione, C.R. Frascati, Via Enrico Fermi 45, 00044, Frascati, Roma (Italy); Dattoli, G.; Di Palma, E.; Doria, A.; Gallerano, G. P.; Giovenale, E.; Spassovsky, I.; Surrenti, V. [ENEA UTAPRAD, C.R. Frascati, Via Enrico Fermi 45, 00044, Frascati, Roma (Italy); Mirizzi, F. [Consorzio CREATE, Via Claudio 21, 80125, Napoli (Italy)

    2014-02-12

    Heating and Current Drive systems are of outstanding relevance in fusion plasmas, magnetically confined in tokamak devices, as they provide the tools to reach, sustain and control burning conditions. Heating systems based on the electron cyclotron resonance (ECRH) have been extensively exploited on past and present machines DEMO, and the future reactor will require high frequencies. Therefore, high power (≥1MW) RF sources with output frequency in the 200 - 300 GHz range would be necessary. A promising source is the so called Cyclotron Auto-Resonance Maser (CARM). Preliminary results of the conceptual design of a CARM device for plasma heating, carried out at ENEA-Frascati will be presented together with the planned R and D development.

  8. Magnet tests and status of the superconducting electron cyclotron resonance source SERSE

    Energy Technology Data Exchange (ETDEWEB)

    Ciavola, G.; Gammino, S.; Cafici, M.; Castro, M.; Chines, F.; Marletta, S. [INFN-Laboratorio Nazionale del Sud, Via S. Sofia 44, 95123 Catania (Italy); Alessandria, F. [INFN-LASA, Via F.lli Cervi 201, 20090 Segrate (Midway Islands) (Italy); Bourg, F.; Briand, P.; Melin, G.; Lagnier, R.; Seyfert, P. [CEA-Departement de Recherche Fondamentale sur la Matiere Condensee, Centre detudes Nucleaires de Grenoble, 38054 Grenoble Cedex 9 (France); Gaggero, G.; Losasso, M.; Penco, R. [ANSALDO-GIE, Via N. Lorenzi 8, 16152 Genova (Italy)

    1996-03-01

    At Laboratorio Nazionale del Sud a superconducting 14.5 GHz electron cyclotron resonance (ECR) source will be used as injector for the K-800 superconducting cyclotron. The original project of its magnetic system has been upgraded by taking into account the results of the high B mode operation of the 6.4 GHz SC-ECRIS at MSU-NSCL and now the mirror field may achieve 2.7 T, which is much higher than the confining field of any other ECR source. The magnet design will allow us to operate in a wide range of magnetic configurations making it easy to tune the source. The status of the project will be outlined and the preliminary results of the tests of the superconducting magnets will be described. A brief description of the tests to be carried out on the source during the first period of operation on the test bench in Grenoble follows. {copyright} {ital 1996 American Institute of Physics.}

  9. Results of RIKEN superconducting electron cyclotron resonance ion source with 28 GHz.

    Science.gov (United States)

    Higurashi, Y; Ohnishi, J; Nakagawa, T; Haba, H; Tamura, M; Aihara, T; Fujimaki, M; Komiyama, M; Uchiyama, A; Kamigaito, O

    2012-02-01

    We measured the beam intensity of highly charged heavy ions and x-ray heat load for RIKEN superconducting electron cyclotron resonance ion source with 28 GHz microwaves under the various conditions. The beam intensity of Xe(20+) became maximum at B(min) ∼ 0.65 T, which was ∼65% of the magnetic field strength of electron cyclotron resonance (B(ECR)) for 28 GHz microwaves. We observed that the heat load of x-ray increased with decreasing gas pressure and field gradient at resonance zone. It seems that the beam intensity of highly charged heavy ions with 28 GHz is higher than that with 18 GHz at same RF power.

  10. Studies on a Q/A selector for the SECRAL electron cyclotron resonance ion source

    Science.gov (United States)

    Yang, Y.; Sun, L. T.; Feng, Y. C.; Fang, X.; Lu, W.; Zhang, W. H.; Cao, Y.; Zhang, X. Z.; Zhao, H. W.

    2014-08-01

    Electron cyclotron resonance ion sources are widely used in heavy ion accelerators in the world because they are capable of producing high current beams of highly charged ions. However, the design of the Q/A selector system for these devices is challenging, because it must have a sufficient ion resolution while controlling the beam emittance growth. Moreover, this system has to be matched for a wide range of ion beam species with different intensities. In this paper, research on the Q/A selector system at the SECRAL (Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou) platform both in experiment and simulation is presented. Based on this study, a new Q/A selector system has been designed for SECRAL II. The features of the new design including beam simulations are also presented.

  11. MM-wave cyclotron auto-resonance maser for plasma heating

    Science.gov (United States)

    Ceccuzzi, S.; Dattoli, G.; Di Palma, E.; Doria, A.; Gallerano, G. P.; Giovenale, E.; Mirizzi, F.; Spassovsky, I.; Ravera, G. L.; Surrenti, V.; Tuccillo, A. A.

    2014-02-01

    Heating and Current Drive systems are of outstanding relevance in fusion plasmas, magnetically confined in tokamak devices, as they provide the tools to reach, sustain and control burning conditions. Heating systems based on the electron cyclotron resonance (ECRH) have been extensively exploited on past and present machines DEMO, and the future reactor will require high frequencies. Therefore, high power (≥1MW) RF sources with output frequency in the 200 - 300 GHz range would be necessary. A promising source is the so called Cyclotron Auto-Resonance Maser (CARM). Preliminary results of the conceptual design of a CARM device for plasma heating, carried out at ENEA-Frascati will be presented together with the planned R&D development.

  12. Kinetic Alfv\\'{e}n turbulence below and above ion-cyclotron frequency

    CERN Document Server

    Zhao, J S; Wu, D J; Yu, M Y

    2015-01-01

    Alfv\\'{e}nic turbulent cascade perpendicular and parallel to the background magnetic field is studied accounting for anisotropic dispersive effects and turbulent intermittency. The perpendicular dispersion and intermittency make the perpendicular-wavenumber magnetic spectra steeper and speed up production of high ion-cyclotron frequencies by the turbulent cascade. On the contrary, the parallel dispersion makes the spectra flatter and decelerate the frequency cascade above the ion-cyclotron frequency. Competition of the above factors results in spectral indices distributed in the interval [-2,-3], where -2 is the index of high-frequency space-filling turbulence, and -3 is the index of low-frequency intermittent turbulence formed by tube-like fluctuations. Spectra of fully intermittent turbulence fill a narrower range of spectral indices [-7/3,-3], which almost coincides with the range of indexes measured in the solar wind. This suggests that the kinetic-scale turbulent spectra are shaped mainly by dispersion a...

  13. Medium to large scale radioisotope production for targeted radiotherapy using a small PET cyclotron

    DEFF Research Database (Denmark)

    Thisgaard, Helge; Jensen, Mikael; Elema, Dennis Ringkjøbing

    2011-01-01

    In recent years the use of radionuclides in targeted cancer therapy has increased. In this study we have developed a high-current solid target system and demonstrated that by the use of a typical low-energy medical cyclotron, it is possible to produce tens of GBq's of many unconventional radionuc......In recent years the use of radionuclides in targeted cancer therapy has increased. In this study we have developed a high-current solid target system and demonstrated that by the use of a typical low-energy medical cyclotron, it is possible to produce tens of GBq's of many unconventional...... radionuclides relevant for cancer therapy such as 64Cu and 119Sb locally at the hospitals....

  14. A preliminary study of a negative hydrogen PIG-type ion source for the compact cyclotron

    Institute of Scientific and Technical Information of China (English)

    YANG Zhen; LONG Ji-Dong; DONG Pan; WANG Tao; WEI Tao; HE Xiao-Zhong; ZHANG Kai-Zhi; SHI Jin-Shui

    2012-01-01

    A Penning ion gauge (PIG)-type ion source has been used for the generation of negative hydrogen ions (H-) as the internal ion source of the compact cyclotron.The discharge characteristics of the ion source are systematically studied for hydrogen operation at different discharge currents and gas flow rates on the prototype cyclotron.The preliminary study results for the low DC voltage H- extraction measurements are presented in this paper.The H- beam current is measured by the order of magnitude from several tens to hundreds of microamperes at different parameter conditions.The discussion and analysis for the experimental results are good for improving the design and working stability of the ion source.

  15. Proton and He2+ Temperature Anisotropies in the Solar Wind Driven by Ion Cyclotron Waves

    Institute of Scientific and Technical Information of China (English)

    Quan-Ming Lu; Shui Wang

    2005-01-01

    We carried out one-dimensional hybrid simulations of resonant scattering of protons and He2+ ions by ion cyclotron waves in an initially homogeneous,collisionless and magnetized plasma. The initial ion cyclotron waves have a power spectrum and propagate both outward and inward. Due to the resonant interaction with the protons and He2+ ions, the wave power will be depleted in the resonance region. Both the protons and He2+ ions can be resonantly heated in the direction perpendicular to the ambient magnetic field and leading to anisotropic velocity distributions, with the anisotropy higher for the He2+ ions than for the protons.At the same time, the anisotropies of the protons and He2+ ions are inversely correlated with the plasma β||p = 87πnpkBT||p/B20, consistent with the prediction of the quasilinear theory (QLT).

  16. Vortex Dynamics and Shear-Layer Instability in High-Intensity Cyclotrons

    Science.gov (United States)

    Cerfon, Antoine J.

    2016-04-01

    We show that the space-charge dynamics of high-intensity beams in the plane perpendicular to the magnetic field in cyclotrons is described by the two-dimensional Euler equations for an incompressible fluid. This analogy with fluid dynamics gives a unified and intuitive framework to explain the beam spiraling and beam breakup behavior observed in experiments and in simulations. Specifically, we demonstrate that beam breakup is the result of a classical instability occurring in fluids subject to a sheared flow. We give scaling laws for the instability and predict the nonlinear evolution of beams subject to it. Our work suggests that cyclotrons may be uniquely suited for the experimental study of shear layers and vortex distributions that are not achievable in Penning-Malmberg traps.

  17. Proton Cyclotron Waves Upstream from Mars: Observations from Mars Global Surveyor

    CERN Document Server

    Romanelli, Norberto; Gomez, Daniel; Mazelle, Christian; Delva, Magda

    2013-01-01

    We present a study on the properties of electromagnetic plasma waves in the region upstream of the Martian bow shock, detected by the magnetometer and electron reflectometer (MAG / ER) onboard the Mars Global Surveyor (MGS) spacecraft during the period known as Science Phasing Orbits (SPO). The frequency of these waves, measured in the MGS reference frame (SC), is close to the local proton cyclotron frequency. Minimum variance analysis (MVA) shows that these 'proton cyclotron frequency' waves (PCWs) are characterized - in the SC frame - by a left-hand, elliptical polarization and propagate almost parallel to the background magnetic field. They also have a small degree of compressibility and an amplitude that decreases with the increase of the interplanetary magnetic field (IMF) cone angle and radial distance from the planet. The latter result supports the idea that the source of these waves is Mars. In addition, we find that these waves are not associated with the foreshock . Empirical evidence and theoretica...

  18. Kinetic simulation of the electron-cyclotron maser instability: effect of a finite source size

    CERN Document Server

    Kuznetsov, A A

    2012-01-01

    The electron-cyclotron maser instability is widespread in the Universe, producing, e.g., radio emission of the magnetized planets and cool substellar objects. Diagnosing the parameters of astrophysical radio sources requires comprehensive nonlinear simulations of the radiation process. We simulate the electron-cyclotron maser instability in a very low-beta plasma. The model used takes into account the radiation escape from the source region and the particle flow through this region. We developed a kinetic code to simulate the time evolution of an electron distribution in a radio emission source. The model includes the terms describing the particle injection to and escape from the emission source region. The spatial escape of the emission from the source is taken into account by using a finite amplification time. The unstable electron distribution of the horseshoe type is considered. A number of simulations were performed for different parameter sets typical of the magnetospheres of planets and ultracool dwarf...

  19. Sensitive test for ion-cyclotron resonant heating in the solar wind.

    Science.gov (United States)

    Kasper, Justin C; Maruca, Bennett A; Stevens, Michael L; Zaslavsky, Arnaud

    2013-03-01

    Plasma carrying a spectrum of counterpropagating field-aligned ion-cyclotron waves can strongly and preferentially heat ions through a stochastic Fermi mechanism. Such a process has been proposed to explain the extreme temperatures, temperature anisotropies, and speeds of ions in the solar corona and solar wind. We quantify how differential flow between ion species results in a Doppler shift in the wave spectrum that can prevent this strong heating. Two critical values of differential flow are derived for strong heating of the core and tail of a given ion distribution function. Our comparison of these predictions to observations from the Wind spacecraft reveals excellent agreement. Solar wind helium that meets the condition for strong core heating is nearly 7 times hotter than hydrogen on average. Ion-cyclotron resonance contributes to heating in the solar wind, and there is a close link between heating, differential flow, and temperature anisotropy.

  20. Electron Cyclotron Current Drive at High Electron Temperature on DIII-D

    Science.gov (United States)

    Petty, C. C.; Austin, M. E.; Harvey, R. W.; Lohr, J.; Luce, T. C.; Makowski, M. A.; Prater, R.

    2007-09-01

    Experiments on DIII-D have measured the electron cyclotron current drive (ECCD) efficiency for co- and counter-injection in low density plasmas with radiation temperatures from electron cyclotron emission (ECE) above 20 keV. The radiation temperature is generally higher than the Thomson scattering temperature, indicating that there is a significant population of non-thermal electrons. The experimental ECCD profile measured with motional Stark effect (MSE) polarimetry is found to agree with quasi-linear theory except for the highest power density cases (QEC/ne2≫1). Radial transport of the energetic electrons with diffusion coefficients of ˜0.4 m2/s is needed to model the broadened ECCD profile at high power density.