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Review of Scientific Instruments

Issue 12 • Date Dec 2012

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Displaying Results 1 - 25 of 73
  • Invited Review Article: High-speed flexure-guided nanopositioning: Mechanical design and control issues

    Page(s): 121101 - 121101-22
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    Recent interest in high-speed scanning probe microscopy for high-throughput applications including video-rate atomic force microscopy and probe-based nanofabrication has sparked attention on the development of high-bandwidth flexure-guided nanopositioning systems (nanopositioners). Such nanopositioners are designed to move samples with sub-nanometer resolution with positioning bandwidth in the kilohertz range. State-of-the-art designs incorporate uniquely designed flexure mechanisms driven by compact and stiff piezoelectric actuators. This paper surveys key advances in mechanical design and control of dynamic effects and nonlinearities, in the context of high-speed nanopositioning. Future challenges and research topics are also discussed. View full abstract»

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  • Efficient copper vapor laser using metal (Cu, Ag) chlorides in thermal insulation and performance with new prism resonator configurations

    Page(s): 123101 - 123101-6
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    A copper vapor laser based on the use of copper chloride and silver chloride mixture embedded inside the laser head thermal insulation is successfully demonstrated. The use of external HCl generator cell containing zirconium chloride normally used for its kinetically enhanced mode of operation is completely eliminated. With this new configuration laser power of ∼70 W was achieved from a wide aperture ∼47–50 mm bore discharge tube with input power of ∼5 kW and overall high efficiency of ∼1.4% without external supply of HCl vapors to the laser head. In a typical operational cycle the laser initially operates as low temperature CuCl laser with startup time of few minutes and output power of ∼10 W during low tube temperature range of ∼300–500 °C. Thereafter, the laser transforms itself into efficient kinetically enhanced copper vapor laser (CVL) at high temperature range of ∼1200–1600 °C with maximum laser output power of ∼70 W. This dual mode of operation observed in a single CVL system is unique and has not been reported so far in any high temperature copper vapor laser. New resonator configurations, namely, the prism resonator in stable and unstable form are successfully demonstrated for the first time in a copper vapor laser to achieve low divergence beam with dramatic increase in misalignment tolerance to ∼25 mrad, which is an improvement of about ∼50 times compared to standard CVLs with conventional spherical or plane-plane resonators. With these new resonator configurations the CVL functions almost as an “alignment free laser” system with significantly reduced beam divergence of ∼0.2 mrad and high optical extraction efficiency of ∼70%–80%. View full abstract»

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  • Proton induced quasi-monochromatic x-ray beams for soft x-ray spectroscopy studies and selective x-ray fluorescence analysis

    Page(s): 123102 - 123102-8
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    We present the analytical features and performance of an x-ray spectroscopy end station of moderate energy resolution operating with proton-induced quasi-monochromatic x-ray beams. The apparatus was designed, installed and operated at the 5.5 MV Tandem VdG Accelerator Laboratory of the Institute of Nuclear Physics, N.C.S.R. “Demokritos,” Athens. The setup includes a two-level ultrahigh vacuum chamber that hosts in the lower level up to six primary targets in a rotatable holder; there, the irradiation of pure element materials—used as primary targets—with few-MeV high current (∼μA) proton beams produces intense quasi-monochromatic x-ray beams of selectable energy. In the chamber's upper level, a six-position rotatable sample holder hosts the targets considered for x-ray spectroscopy studies. The proton-induced x-ray beam, after proper collimation, is guided to the sample position whereas various filters can be also inserted along the beam's path to eliminate the backscattered protons or/and to absorb selectively components of the x-ray beam. The apparatus incorporates an ultrathin window Si(Li) spectrometer (FWHM 136 eV at 5.89 keV) coupled with low-noise electronics capable of efficiently detecting photons down to carbon Kα. Exemplary soft x-ray spectroscopy studies and results of selective x-ray fluorescence analysis are presented. View full abstract»

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  • Superconducting single-photon counting system for optical experiments requiring time-resolution in the picosecond range

    Page(s): 123103 - 123103-5
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    We have developed a cryogenic measurement system for single-photon counting, which can be used in optical experiments requiring high time resolution in the picosecond range. The system utilizes niobium nitride superconducting nanowire single-photon detectors which are integrated in a time-correlated single-photon counting (TCSPC) setup. In this work, we describe details of the mechanical design, the electrical setup, and the cryogenic optical components. The performance of the complete system in TCSPC mode is tentatively benchmarked using 140 fs long laser pulses at a repetition frequency of 75 MHz. Due to the high temporal stability of these pulses, the measured time resolution of 35 ps (FWHM) is limited by the timing jitter of the measurement system. The result was cross-checked in a Coherent Anti-stokes Raman Scattering (CARS) setup, where scattered pulses from a β-barium borate crystal have been detected with the same time resolution. View full abstract»

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  • A high precision instrument to measure angular and binocular deviation introduced by aircraft windscreens by using a shadow casting technique

    Page(s): 123104 - 123104-5
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    Objects viewed through transparent sheets with residual non-parallelism and irregularity appear shifted and distorted. This distortion is measured in terms of angular and binocular deviation of an object viewed through the transparent sheet. The angular and binocular deviations introduced are particularly important in the context of aircraft windscreens and canopies as they can interfere with decision making of pilots especially while landing, leading to accidents. In this work, we have developed an instrument to measure both the angular and binocular deviations introduced by transparent sheets. This instrument is especially useful in the qualification of aircraft windscreens and canopies. It measures the deviation in the geometrical shadow cast by a periodic dot pattern trans-illuminated by the distorted light beam from the transparent test specimen compared to the reference pattern. Accurate quantification of the shift in the pattern is obtained by cross-correlating the reference shadow pattern with the specimen shadow pattern and measuring the location of the correlation peak. The developed instrument is handy to use and computes both angular and binocular deviation with an accuracy of less than ±0.1 mrad (≈0.036 mrad) and has an excellent repeatability with an error of less than 2%. View full abstract»

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  • Development of vacuum ultraviolet absorption spectroscopy system for wide measurement range of number density using a dual-tube inductively coupled plasma light source

    Page(s): 123105 - 123105-3
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    A vacuum ultraviolet absorption spectroscopy system for a wide measurement range of atomic number densities is developed. Dual-tube inductively coupled plasma was used as a light source. The probe beam profile was optimized for the target number density range by changing the mass flow rate of the inner and outer tubes. This system was verified using cold xenon gas. As a result, the measurement number density range was extended from the conventional two orders to five orders of magnitude. View full abstract»

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  • Active diffraction gratings: Development and tests

    Page(s): 123106 - 123106-5
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    We present the realization and characterization of an active spherical diffraction grating with variable radius of curvature to be used in grazing-incidence monochromators. The device consists of a bimorph deformable mirror on the top of which a diffraction grating with laminar profile is realized by UV lithography. The experimental results show that the active grating can optimize the beam focalization of visible wavelengths through its rotation and focus accommodation. View full abstract»

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  • Electron-recoil ion and recoil ion-projectile coincidence techniques applied to obtain absolute partial collision cross sections

    Page(s): 123107 - 123107-8
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    We present in detail an alternative experimental set-up and data analysis, based on the electron-recoil ion and recoil ion-projectile coincidence techniques, that enable the measurement of partial pure ionization and partial charge exchange cross sections for an effusive gas jet set-up, where the absolute target density and recoil ion efficiency cannot be measured directly. The method is applied to the ionization of helium atoms due to collision with partially stripped C3 + projectiles. In order to check the method, the results are compared to data available in the literature where the target density and recoil ion detection efficiency were measured directly. The pure ionization channel is compared to the electron capture channel. View full abstract»

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  • High precision magnetic linear dichroism measurements in (Ga,Mn)As

    Page(s): 123108 - 123108-10
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    Investigation of magnetic materials using the first-order magneto-optical Kerr effects (MOKEs) is well established and is frequently used. On the other hand, the utilization of the second-order (or quadratic) magneto-optical (MO) effects for the material research is rather rare. This is due to the small magnitude of quadratic MO signals and the fact that the signals are even in magnetization (i.e., they do not change a sign when the magnetization orientation is reversed), which makes it difficult to separate second-order MO signals from various experimental artifacts. In 2005 a giant quadratic MO effect—magnetic linear dichroism (MLD)—was observed in the ferromagnetic semiconductor (Ga,Mn)As. This discovery not only provided a new experimental tool for the investigation of in-plane magnetization dynamics in (Ga,Mn)As using light at normal incidence, but it also motivated the development of experimental techniques for the measurement of second-order MO effects in general. In this paper we compare four different experimental techniques that can be used to measure MLD and to separate it from experimental artifacts. We show that the most reliable results are obtained when we monitor the polarization of reflected light while the magnetization of the sample is rotated by applying an external magnetic field. Using this technique we measure the MLD spectra of (Ga,Mn)As in a broad spectral range from 0.1 eV to 2.7 eV and we observe that MLD has a magnitude comparable to the polar MOKE signals in this material. View full abstract»

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  • A setup for resonant inelastic soft x-ray scattering on liquids at free electron laser light sources

    Page(s): 123109 - 123109-8
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    We present a flexible and compact experimental setup that combines an in vacuum liquid jet with an x-ray emission spectrometer to enable static and femtosecond time-resolved resonant inelastic soft x-ray scattering (RIXS) measurements from liquids at free electron laser (FEL) light sources. We demonstrate the feasibility of this type of experiments with the measurements performed at the Linac Coherent Light Source FEL facility. At the FEL we observed changes in the RIXS spectra at high peak fluences which currently sets a limit to maximum attainable count rate at FELs. The setup presented here opens up new possibilities to study the structure and dynamics in liquids. View full abstract»

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  • Characteristics of a cylindrical collector mirror for laser-produced xenon plasma soft X-rays and improvement of mirror lifetime by buffer gas

    Page(s): 123110 - 123110-5
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    The focusing characteristics of a ruthenium-coated cylindrical mirror were investigated on the basis of its ability to collect and focus broadband 5–17-nm soft X-rays emitted from a laser-produced plasma. Based on the plasmas spectral intensity distribution and the reflectivity function of the mirror, we defined the optimum position of the integrated cylindrical mirror at which the X-ray energy flux transported and focused through the mirror was maximum. A minimum spot diameter of 22 mm at a distance of approximately 200 mm from a soft X-ray source was confirmed. The maximum intensity of the collected soft X-rays was 1.3 mJ/cm2 at the center of the irradiation zone. Thus, the irradiation intensity was improved by approximately 27 times when compared to that of 47 μJ/cm2 without the mirror. The debris sputtering rate on the reflection surface of the mirror can be reduced to 1/110 by argon gas at 11 Pa, while the attenuation rate of the soft X-rays due to absorption by the buffer gas can be suppressed to less than 10% at the focal point. The focusing property of the mirror is expected to be maintained for 3000 h or longer without significant degradation for a 100 W/320 pps laser shot if the ruthenium layer is thicker than 10 μm. These results suggest that a stand-alone broadband soft X-ray processing system can be realized by using laser-produced plasma soft X-rays. View full abstract»

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  • A scintillator-based online detector for the angularly resolved measurement of laser-accelerated proton spectra

    Page(s): 123301 - 123301-7
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    In recent years, a new generation of high repetition rate (∼10 Hz), high power (∼100 TW) laser systems has stimulated intense research on laser-driven sources for fast protons. Considering experimental instrumentation, this development requires online diagnostics for protons to be added to the established offline detection tools such as solid state track detectors or radiochromic films. In this article, we present the design and characterization of a scintillator-based online detector that gives access to the angularly resolved proton distribution along one spatial dimension and resolves 10 different proton energy ranges. Conceived as an online detector for key parameters in laser-proton acceleration, such as the maximum proton energy and the angular distribution, the detector features a spatial resolution of ∼1.3 mm and a spectral resolution better than 1.5 MeV for a maximum proton energy above 12 MeV in the current design. Regarding its areas of application, we consider the detector a useful complement to radiochromic films and Thomson parabola spectrometers, capable to give immediate feedback on the experimental performance. The detector was characterized at an electrostatic Van de Graaff tandetron accelerator and tested in a laser-proton acceleration experiment, proving its suitability as a diagnostic device for laser-accelerated protons. View full abstract»

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  • Nonlinear transmission line based electron beam driver

    Page(s): 123302 - 123302-4
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    Gated field emission cathodes can provide short electron pulses without the requirement of laser systems or cathode heating required by photoemission or thermionic cathodes. The large electric field requirement for field emission to take place can be achieved by using a high aspect ratio cathode with a large field enhancement factor which reduces the voltage requirement for emission. In this paper, a cathode gate driver based on the output pulse train from a nonlinear transmission line is experimentally demonstrated. The application of the pulse train to a tufted carbon fiber field emission cathode generates short electron pulses. The pulses are approximately 2 ns in duration with emission currents of several mA, and the train contains up to 6 pulses at a frequency of 100 MHz. Particle-in-cell simulation is used to predict the characteristic of the current pulse train generated from a single carbon fiber field emission cathode using the same technique. View full abstract»

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  • Magnetic emittance suppression using a bucking coil for a dc photocathode electron gun

    Page(s): 123303 - 123303-5
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    Magnetic emittance suppression was demonstrated using a bucking coil for a dc photocathode electron gun. The magnetic emittance is derived from a leakage magnetic field on the cathode surface originating from a solenoid lens, and is important for realizing a high brightness dc photocathode electron gun. In order to solve this problem, a bucking coil integrated solenoid lens has been developed. The solenoid lens consists of a main coil, a bucking coil, and a pure iron yoke. The bucking coil and the main coil are integrated in the same yoke in order to prevent distortion of the magnetic field due to misalignment of the two coils. The emittance was measured and calculated as a function of the exciting current of the bucking coil and as a function of the electron beam size on the cathode. View full abstract»

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  • A model of the generation and transport of ozone in high-tension nozzle driven corona inside a novel diode

    Page(s): 123304 - 123304-11
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    The genesis and transport of ozone (O3) are investigated in a novel plasma diode and described in this paper. The innovative cathode (K) of this axial symmetric diode which operated at the high voltage (ϕ0), has a large number of sharpened nozzles located on different radial planes of its central tubular-mast and is encircled by the anode (A). The nozzles played the dual role of oxygen (O2) injection as well as creation of high electric field (E) in the A-K gap, enabled the formation of a cold corona. Electrons in the corona under the influence of E moved towards anode, collided with O2 and created the O radicals. O in turn joined the free O2 and formed O3. The evolution of O3 here is modeled in various O2 pressure (P), electron density (ne), and temperature (T) in terms of the major reaction modes involving e, O, O2, and O3. Typical steady state O3 density attained so in P ∼ bar, ne ∼ 1015 m-3 and T ∼ 300 K is over 1025 m-3 and that of O lower ∼1020 m-3. Both the O and O3 densities increased with an enhanced ne of avalanche multiplications in corona. O3 increased also with a higher P but the temporal O reversed in trend midway and reduced with P towards the steady state. A sharp decline in diode resistance with smaller A-K gap induced finite discharge current and led to the undesired heating of corona. It is shown that the O3 density reduced with the temperature rise but O density reduced with the T rise up to 500 K and then rose modestly with the further T increase. View full abstract»

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  • Controllable evaporation of cesium from a dispenser oven

    Page(s): 123305 - 123305-5
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    This instrument allows controlled evaporation of the alkali metal cesium over a wide range of evaporation rates. The oven has three unique features. The first is an alkali metal reservoir that uses a dispenser as a cesium source. The heating current of the dispenser controls the evaporation rate allowing generation of an adjustable and stable flow of pure cesium. The second is a blocking valve, which is fully metallic as is the body of the oven. This construction both reduces contamination of the dispenser and enables the oven to be operated up to 300 °C, with only small temperature variations (<5 °C). By minimizing the temperature variation, the built up of the alkali metal at a cold spot is significantly hindered. The last feature is an integral surface ionization detector for measuring and controlling the evaporation rate. The dispenser oven can be easily transferred to the other alkali-metals. View full abstract»

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  • Polarization pyrometry: An improvement to multi-wavelength optical pyrometry

    Page(s): 123501 - 123501-6
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    We describe a new method that improves upon temperature measurement by optical pyrometry. The main uncertainty in the traditional pyrometry technique is the surface emissivity, which is generally unknown and hard to measure. A common approach to deal with this problem is to measure the thermal emission at multiple wavelengths – an approach called multi-wavelength pyrometry. However, this technique can still result in a level of uncertainty in the surface temperature that is unsatisfactory for scientific applications, such as a measurement of equation of state of warm dense matter. In contrast to the conventional multi-wavelength technique, in the polarization pyrometry approach described herein, p- and s-polarization components of thermal radiation at multiple-angles are used to deduce the temperature. This paper describes the concept and the results of an initial proof-of-principle static experiment with an electrically heated tungsten ribbon. It was found that in the same experiment, the accuracy of the polarization pyrometry measurement was substantially greater than that achieved using conventional multi-wavelength pyrometry. View full abstract»

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  • Development of large volume double ring penning plasma discharge source for efficient light emissions

    Page(s): 123502 - 123502-7
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    In this paper, the development of large volume double ring Penning plasma discharge source for efficient light emissions is reported. The developed Penning discharge source consists of two cylindrical end cathodes of stainless steel having radius 6 cm and a gap 5.5 cm between them, which are fitted in the top and bottom flanges of the vacuum chamber. Two stainless steel anode rings with thickness 0.4 cm and inner diameters 6.45 cm having separation 2 cm are kept at the discharge centre. Neodymium (Nd2Fe14B) permanent magnets are physically inserted behind the cathodes for producing nearly uniform magnetic field of ∼0.1 T at the center. Experiments and simulations have been performed for single and double anode ring configurations using helium gas discharge, which infer that double ring configuration gives better light emissions in the large volume Penning plasma discharge arrangement. The optical emission spectroscopy measurements are used to complement the observations. The spectral line-ratio technique is utilized to determine the electron plasma density. The estimated electron plasma density in double ring plasma configuration is ∼2 × 1011 cm-3, which is around one order of magnitude larger than that of single ring arrangement. View full abstract»

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  • Compact high-speed reciprocating probe system for measurements in a Hall thruster discharge and plume

    Page(s): 123503 - 123503-5
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    A compact high-speed reciprocating probe system has been developed in order to perform measurements of the plasma parameters by means of electrostatic probes in the discharge and the plume of a Hall thruster. The system is based on a piezoelectric linear drive that can achieve a speed of up to 350 mm/s over a travel range of 90 mm. Due to the high velocity of the linear drive the probe can be rapidly moved in and out the measurement region in order to minimize perturbation of the thruster discharge due to sputtering of probe material. To demonstrate the impact of the new system, a heated emissive probe, installed on the high-speed translation stage, was used to measure the plasma potential and the electron temperature in the near-field plume of a low power Hall thruster. View full abstract»

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  • A laser-induced repetitive fast neutron source applied for gold activation analysis

    Page(s): 123504 - 123504-5
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    A laser-induced repetitively operated fast neutron source was developed for applications in laser-driven nuclear physics research. The developed neutron source, which has a neutron yield of approximately 4 × 105 n/pulse and can be operated up to a pulse repetition rate of 10 Hz, was applied for a gold activation analysis. Relatively strong delayed gamma spectra of the activated gold were measured at 333 keV and 355 keV, and proved the possibility of the neutron source for activation analyses. In addition, the nuclear reactions responsible for the measured gamma spectra of gold were elucidated by the 14 MeV fast neutrons resulting from the D(t,n)He4 nuclear reaction, for which the required tritium originated from the primary fusion reaction, D(d,p)T3. View full abstract»

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  • Advanced Thomson scattering system for high-flux linear plasma generator

    Page(s): 123505 - 123505-12
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    An advanced Thomson scattering system has been built for a linear plasma generator for plasma surface interaction studies. The Thomson scattering system is based on a Nd:YAG laser operating at the second harmonic and a detection branch featuring a high etendue (f /3) transmission grating spectrometer equipped with an intensified charged coupled device camera. The system is able to measure electron density (ne) and temperature (Te) profiles close to the output of the plasma source and, at a distance of 1.25 m, just in front of a target. The detection system enables to measure 50 spatial channels of about 2 mm each, along a laser chord of 95 mm. By summing a total of 30 laser pulses (0.6 J, 10 Hz), an observational error of 3% in ne and 6% in Te (at ne = 9.4 × 1018 m-3) can be obtained. Single pulse Thomson scattering measurements can be performed with the same accuracy for ne > 2.8 × 1020 m-3. The minimum measurable density and temperature are ne < 1 × 1017 m-3 and Te < 0.07 eV, respectively. In addition, using the Rayleigh peak, superimposed on the Thomson scattered spectrum, the neutral density (n0) of the plasma can be measured with an accuracy of 25% (at n0 = 1 × 1020 m-3). In this report, the performance of the Thomson scattering system will be shown along with unprecedented accurate Thomson-Rayleigh scattering measurements on a low-temperature argon plasma expansion into a low-pressure background. View full abstract»

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  • New dual gas puff imaging system with up-down symmetry on experimental advanced superconducting tokamak

    Page(s): 123506 - 123506-7
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    Gas puff imaging (GPI) offers a direct and effective diagnostic to measure the edge turbulence structure and velocity in the edge plasma, which closely relates to edge transport and instability in tokamaks. A dual GPI diagnostic system has been installed on the low field side on experimental advanced superconducting tokamak (EAST). The two views are up-down symmetric about the midplane and separated by a toroidal angle of 66.6°. A linear manifold with 16 holes apart by 10 mm is used to form helium gas cloud at the 130×130 mm (radial versus poloidal) objective plane. A fast camera is used to capture the light emission from the image plane with a speed up to 390 804 frames/s with 64×64 pixels and an exposure time of 2.156 μs. The spatial resolution of the system is 2 mm at the objective plane. A total amount of 200 Pa.L helium gas is puffed into the plasma edge for each GPI viewing region for about 250 ms. The new GPI diagnostic has been applied on EAST for the first time during the recent experimental campaign under various plasma conditions, including ohmic, L-mode, and type-I, and type-III ELMy H-modes. Some of these initial experimental results are also presented. View full abstract»

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  • Separation of finite electron temperature effect on plasma polarimetry

    Page(s): 123507 - 123507-5
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    This study demonstrates the separation of the finite electron temperature on the plasma polarimetry in the magnetic confined fusion plasma for the first time. Approximate solutions of the transformed Stokes equation, including the relativistic effect, suggest that the orientation angle, θ, and ellipticity angle, ε, of polarization state have different dependency on the electron density, ne, and the electron temperature, Te, and that the separation of ne and Te from θ and ε is possible in principle. We carry out the equilibrium and kinetic reconstruction of tokamak plasma when the central electron density was 1020 m-3, and the central electron temperatures were 5, 10, 20, and 30 keV. For both cases when a total plasma current, Ip, is known and when Ip is unknown, the profiles of plasma current density, jϕ, ne, and Te are successfully reconstructed. The reconstruction of jϕ without the information of Ip indicates the new method of Ip measurement applicable to steady state operation of tokamak. View full abstract»

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  • A novel time stamping technique for distributed data acquisition systems

    Page(s): 123508 - 123508-6
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    In this paper, we discuss the design and implementation of a synchronizing technique for data acquisition systems, which can effectively use the normal, standard local area network cables to provide a time stamp, with a range up to 32 days, resolution of 10 ns, and synchronization within ± 5 ns. This system may be used to synchronize data being collected by independent heterogeneous data acquisition modules, that acquire events independently. Such distributed systems are generally designed with a tree-like structure or independent self-triggered acquisition boxes. These leaf edges are connected through branches to the root node, via non-bus based inter-connecting links. The present system has been tested with a set of self-triggered digital signal processing based data acquisition engines, having a 100 MHz analog to digital converter front end. View full abstract»

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  • First results on disruption mitigation by massive gas injection in Korea Superconducting Tokamak Advanced Research

    Page(s): 123509 - 123509-6
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    Massive gas injection (MGI) system was developed on Korea Superconducting Tokamak Advanced Research (KSTAR) in 2011 campaign for disruption studies. The MGI valve has a volume of 80 ml and maximum injection pressure of 50 bar, the diameter of valve orifice to vacuum vessel is 18.4 mm, the distance between MGI valve and plasma edge is ∼3.4 m. The MGI power supply employs a large capacitor of 1 mF with the maximum voltage of 3 kV, the valve can be opened in less than 0.1 ms, and the amount of MGI can be controlled by the imposed voltage. During KSTAR 2011 campaign, MGI disruptions are carried out by triggering MGI during the flat top of circular and limiter discharges with plasma current 400 kA and magnetic field 2–3.5 T, deuterium injection pressure 39.7 bar, and imposed voltage 1.1–1.4 kV. The results show that MGI could mitigate the heat load and prevent runaway electrons with proper MGI amount, and MGI penetration is deeper under higher amount of MGI or lower magnetic field. However, plasma start-up is difficult after some of D2 MGI disruptions due to the high deuterium retention and consequently strong outgassing of deuterium in next shot, special effort should be made to get successful plasma start-up after deuterium MGI under the graphite first wall. View full abstract»

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Review of Scientific Instruments, published by the American Institute of Physics, is devoted to scientific instruments, apparatus, and techniques.

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Albert T. Macrander
Argonne National Laboratory