Mammalian plasma membrane proteins as potential biomarkers and drug targets.

PubMed

Rucevic, Marijana; Hixson, Douglas; Josic, Djuro

2011-06-01

Defining the plasma membrane proteome is crucial to understand the role of plasma membrane in fundamental biological processes. Change in membrane proteins is one of the first events that take place under pathological conditions, making plasma membrane proteins a likely source of potential disease biomarkers with prognostic or diagnostic potential. Membrane proteins are also potential targets for monoclonal antibodies and other drugs that block receptors or inhibit enzymes essential to the disease progress. Despite several advanced methods recently developed for the analysis of hydrophobic proteins and proteins with posttranslational modifications, integral membrane proteins are still under-represented in plasma membrane proteome. Recent advances in proteomic investigation of plasma membrane proteins, defining their roles as diagnostic and prognostic disease biomarkers and as target molecules in disease treatment, are presented. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Laboratory simulation of space plasma phenomena*

NASA Astrophysics Data System (ADS)

Amatucci, B.; Tejero, E. M.; Ganguli, G.; Blackwell, D.; Enloe, C. L.; Gillman, E.; Walker, D.; Gatling, G.

2017-12-01

Laboratory devices, such as the Naval Research Laboratory's Space Physics Simulation Chamber, are large-scale experiments dedicated to the creation of large-volume plasmas with parameters realistically scaled to those found in various regions of the near-Earth space plasma environment. Such devices make valuable contributions to the understanding of space plasmas by investigating phenomena under carefully controlled, reproducible conditions, allowing for the validation of theoretical models being applied to space data. By working in collaboration with in situ experimentalists to create realistic conditions scaled to those found during the observations of interest, the microphysics responsible for the observed events can be investigated in detail not possible in space. To date, numerous investigations of phenomena such as plasma waves, wave-particle interactions, and particle energization have been successfully performed in the laboratory. In addition to investigations such as plasma wave and instability studies, the laboratory devices can also make valuable contributions to the development and testing of space plasma diagnostics. One example is the plasma impedance probe developed at NRL. Originally developed as a laboratory diagnostic, the sensor has now been flown on a sounding rocket, is included on a CubeSat experiment, and will be included on the DoD Space Test Program's STP-H6 experiment on the International Space Station. In this presentation, we will describe several examples of the laboratory investigation of space plasma waves and instabilities and diagnostic development. *This work supported by the NRL Base Program.

Langmuir Probe Diagnostics of Pulsed Plasma Doping System

NASA Astrophysics Data System (ADS)

Lei, Yu; Overzet, Lawrence J.; Felch, Susan B.; Fang, Ziwei; Koo, Bon-Woong; Goeckner, Matthew J.

2002-10-01

Pulsed plasma doping (P2LAD) is a potential solution to implement ultra-shallow junctions. In this study, Langmuir probe diagnostics techniques were investigated thoroughly for its application to P2LAD system, and the current sensing scheme using batteries and a 'downstairs' load resistor turned out to be the most reliable. Severe limitations of current transformers were found in diagnostics of pulsed plasma. A floating probe was proven to be good at monitoring the disturbances of the Langmuir probe and the cathode voltage. With the above technique, time-resolved Langmuir probe measurements have been carried out in a P2LAD system. The Langmuir probe data in Ar plasma indicate that during a 20 microns long implant pulse the plasma density ranges from 1E9 1E10 cm-3 and the electron temperature ranges from 0.4 to 14 eV. Between the pulses, the density keeps at the high level for 30 ms and then decays exponentially until reaching the range of 3E8 1E9 cm-3, which demonstrates the presence of residual plasma between pulses. A non-zero plasma density during the afterglow is also observed for BF3 plasma. Significant amounts of primary electron and electron beams are present during the ignition and ensuing steady region in both Ar and BF3 plasmas while they are much stronger in BF3 plasma. Plasma density is observed to increase with cathode voltage and pressure while the electron temperature is mainly influenced by the pressure. An overshoot of the cathode voltage during the afterglow region was found, and it significantly influences the plasma potential during the afterglow.

View of the Challenger's payload bay and the Plasma Diagnostic package

NASA Technical Reports Server (NTRS)

1985-01-01

The solar optical universal polarimeter (SOUP) experiment is visible among the cluster of Spacelab 2 hardware in the cargo bay of the Shuttle Challenger. Various components of the instrument positioning system (IPS) are conspicuous at the center of the frame. The Plasma Diagnostic package (PDP) is seen attached to the remote manipulator system (RMS) above the open payload bay.

Numerical calculation of charge exchange cross sections for plasma diagnostics

NASA Astrophysics Data System (ADS)

Mendez, Luis

2016-09-01

The diagnostics of impurity density and temperature in the plasma core in tokamak plasmas is carried out by applying the charge exchange recombination spectroscopy (CXRS) technique, where a fast beam of H atoms collides with the plasma particles leading to electron capture reactions with the impurity ions. The diagnostics is based on the emission of the excited ions formed in the electron capture. The application of the CXRS requires the knowledge of accurate state-selective cross sections, which in general are not accessible experimentally, and the calculation of cross sections for the high n capture levels, required for the diagnostics in the intermediate energy domain of the probe beam, is particularly difficult. In this work, we present a lattice numerical method to solve the time dependent Schrödinger equation. The method is based on the GridTDSE package, it is applicable in the wide energy range 1 - 500 keV/u and can be used to assess the accuracy of previous calculations. The application of the method will be illustrated with calculations for collisions of multiply charged ions with H. Work partially supported by project ENE2014-52432-R (Secretaria de Estado de I+D+i, Spain).

Plasma/Wall interaction of an insulated material by laser-induced fluorescence diagnostic

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

Claire, N.; Doveil, F.

2015-07-01

We present Argon Ion Velocity Distribution Function (IVDF) in the vicinity of an insulated BNSiO{sub 2} ceramic and a glass plate in a non magnetized plasma by laser-induced fluorescence diagnostic. Results show the rather surprising self-consistent formation of a positive or inverse sheath in the two cases. The positive plasma potential repels ions from the insulated wall and is not explained by any sheath theory. Electron secondary emission of the ceramic can be a good candidate to explain these results. (authors)

Upgrades of edge, divertor and scrape-off layer diagnostics of W7-X for OP1.2

DOE PAGES

Hathiramani, D.; Ali, A.; Anda, G.; ...

2018-02-07

In this work, Wendelstein 7-X (W7-X) is the world’s largest superconducting nuclear fusion experiment of the optimized stellarator type. In the first Operation Phase (OP1.1) helium and hydrogen plasmas were studied in limiter configuration. The heating energy was limited to 4 MJ and the main purpose of that campaign was the integral commissioning of the machine and diagnostics, which was achieved very successfully. Already from the beginning a comprehensive set of diagnostics was available to study the plasma. On the path towards high-power, high-performance plasmas, W7-X will be stepwise upgraded from an inertially cooled (OP1.2, limited to 80 MJ) tomore » an actively cooled island divertor (OP2, 10 MW steady-state plasma operation). The machine is prepared for OP1.2 with 10 inertially cooled divertor units, and the experimental campaign has started recently.The paper describes a subset of diagnostics which will be available for OP1.2 to study the plasma edge, divertor and scrape-off layer physics including those already available for OP1.1, plus modifications, upgrades and new systems. In conclusion, the focus of this summary will be on technical and engineering aspects, like feasibility and assembly but also on reliability, thermal loads and shielding against magnetic fields.« less

Note: Additionally refined new possibilities of plasma probe diagnostics.

PubMed

Riaby, V A; Savinov, V P; Masherov, P E; Yakunin, V G

2018-03-01

In two previous Notes published in this journal, a method of measuring probe sheath thickness and ion mass was described using Langmuir probe diagnostics in low pressure xenon plasma close to Maxwellian substance. According to the first Note, this method includes two stages: (i) in a special experiment with known ion mass, the Bohm and Child-Langmuir-Boguslavsky (CLB) equations for cylindrical Langmuir probes used in this xenon plasma were solved jointly to determine the probe sheath thicknesses and Bohm coefficient C BCyl ≈ 1.13; and (ii) in a general experiment, with known C BCyl , the same equations could be solved to obtain the probe sheath thicknesses and the mean ion mass. In the second Note, the (i) stage of this method was refined: the results of the CLB probe sheath model application, which were termed "evaluations," were corrected using the step-front probe sheath model, which was closer to reality in the special experiment with the xenon plasma. This process resulted in a Bohm coefficient of C BCyl ≈ 1.23 for the cylindrical probe. In the present Note, corrected xenon plasma parameters without the influence of the bare probe protective shield were used for the (i) stage of this diagnostic method. This action also refined the Bohm coefficient, lowering it to C BCyl ≈ 0.745 for cylindrical probes. This advance makes the new diagnostics method more objective and reliable.

Note: Additionally refined new possibilities of plasma probe diagnostics

NASA Astrophysics Data System (ADS)

Riaby, V. A.; Savinov, V. P.; Masherov, P. E.; Yakunin, V. G.

2018-03-01

In two previous Notes published in this journal, a method of measuring probe sheath thickness and ion mass was described using Langmuir probe diagnostics in low pressure xenon plasma close to Maxwellian substance. According to the first Note, this method includes two stages: (i) in a special experiment with known ion mass, the Bohm and Child-Langmuir-Boguslavsky (CLB) equations for cylindrical Langmuir probes used in this xenon plasma were solved jointly to determine the probe sheath thicknesses and Bohm coefficient CBCyl ≈ 1.13; and (ii) in a general experiment, with known CBCyl, the same equations could be solved to obtain the probe sheath thicknesses and the mean ion mass. In the second Note, the (i) stage of this method was refined: the results of the CLB probe sheath model application, which were termed "evaluations," were corrected using the step-front probe sheath model, which was closer to reality in the special experiment with the xenon plasma. This process resulted in a Bohm coefficient of CBCyl ≈ 1.23 for the cylindrical probe. In the present Note, corrected xenon plasma parameters without the influence of the bare probe protective shield were used for the (i) stage of this diagnostic method. This action also refined the Bohm coefficient, lowering it to CBCyl ≈ 0.745 for cylindrical probes. This advance makes the new diagnostics method more objective and reliable.

Diagnostics for the plasma liner experiment.

PubMed

Lynn, A G; Merritt, E; Gilmore, M; Hsu, S C; Witherspoon, F D; Cassibry, J T

2010-10-01

The goal of the Plasma Liner Experiment (PLX) is to explore and demonstrate the feasibility of forming imploding spherical "plasma liners" via merging high Mach number plasma jets to reach peak liner pressures of ∼0.1 Mbar using ∼1.5 MJ of initial stored energy. Such a system would provide HED plasmas for a variety of fundamental HEDLP, laboratory astrophysics, and materials science studies, as well as a platform for experimental validation of rad-hydro and rad-MHD simulations. It could also prove attractive as a potential standoff driver for magnetoinertial fusion. Predicted parameters from jet formation to liner stagnation cover a large range of plasma density and temperature, varying from n(i)∼10(16) cm(-3), T(e)≈T(i)∼1 eV at the plasma gun mouth to n(i)>10(19) cm(-3), T(e)≈T(i)∼0.5 keV at stagnation. This presents a challenging problem for the plasma diagnostics suite which will be discussed.

High temperature UF6 RF plasma experiments applicable to uranium plasma core reactors

NASA Technical Reports Server (NTRS)

Roman, W. C.

1979-01-01

An investigation was conducted using a 1.2 MW RF induction heater facility to aid in developing the technology necessary for designing a self critical fissioning uranium plasma core reactor. Pure, high temperature uranium hexafluoride (UF6) was injected into an argon fluid mechanically confined, steady state, RF heated plasma while employing different exhaust systems and diagnostic techniques to simulate and investigate some potential characteristics of uranium plasma core nuclear reactors. The development of techniques and equipment for fluid mechanical confinement of RF heated uranium plasmas with a high density of uranium vapor within the plasma, while simultaneously minimizing deposition of uranium and uranium compounds on the test chamber peripheral wall, endwall surfaces, and primary exhaust ducts, is discussed. The material tests and handling techniques suitable for use with high temperature, high pressure, gaseous UF6 are described and the development of complementary diagnostic instrumentation and measurement techniques to characterize the uranium plasma, effluent exhaust gases, and residue deposited on the test chamber and exhaust system components is reported.

Diagnostic study of multiple double layer formation in expanding RF plasma

NASA Astrophysics Data System (ADS)

Chakraborty, Shamik; Paul, Manash Kumar; Roy, Jitendra Nath; Nath, Aparna

2018-03-01

Intensely luminous double layers develop and then expand in size in a visibly glowing RF discharge produced using a plasma source consisting of a semi-transparent cylindrical mesh with a central electrode, in a linear plasma chamber. Although RF discharge is known to be independent of device geometry in the absence of magnetic field, the initiation of RF discharge using such a plasma source results in electron drift and further expansion of the plasma in the vessel. The dynamics of complex plasma structures are studied through electric probe diagnostics in the expanding RF plasma. The measurements made to study the parametric dependence of evolution of double layer structures are analyzed and presented here. The plasma parameter measurements suggest that the complex potential structures initially form with low potential difference between the layers and then gradually expand producing burst oscillations. The present study provides interesting information about the stability of plasma sheath and charge particle dynamics in it that are important to understand the underlying basic sheath physics along with applications in plasma acceleration and propulsion.

Talbot-Lau x-ray deflectometer electron density diagnostic for laser and pulsed power high energy density plasma experiments (invited)

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

Valdivia, M. P., E-mail: mpvaldivia@pha.jhu.edu; Stutman, D.; Stoeckl, C.

2016-11-15

Talbot-Lau X-ray deflectometry (TXD) has been developed as an electron density diagnostic for High Energy Density (HED) plasmas. The technique can deliver x-ray refraction, attenuation, elemental composition, and scatter information from a single Moiré image. An 8 keV Talbot-Lau interferometer was deployed using laser and x-pinch backlighters. Grating survival and electron density mapping were demonstrated for 25–29 J, 8–30 ps laser pulses using copper foil targets. Moiré pattern formation and grating survival were also observed using a copper x-pinch driven at 400 kA, ∼1 kA/ns. These results demonstrate the potential of TXD as an electron density diagnostic for HED plasmas.

The cluster charge identification in the GEM detector for fusion plasma imaging by soft X-ray diagnostics

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

Czarski, T., E-mail: tomasz.czarski@ifpilm.pl; Chernyshova, M.; Malinowski, K.

2016-11-15

The measurement system based on gas electron multiplier detector is developed for soft X-ray diagnostics of tokamak plasmas. The multi-channel setup is designed for estimation of the energy and the position distribution of an X-ray source. The focal measuring issue is the charge cluster identification by its value and position estimation. The fast and accurate mode of the serial data acquisition is applied for the dynamic plasma diagnostics. The charge clusters are counted in the space determined by 2D position, charge value, and time intervals. Radiation source characteristics are presented by histograms for a selected range of position, time intervals,more » and cluster charge values corresponding to the energy spectra.« less

Circular RNA hsa_circ_0000745 may serve as a diagnostic marker for gastric cancer.

PubMed

Huang, Mei; He, Yi-Ren; Liang, Li-Chuan; Huang, Qiang; Zhu, Zhi-Qiang

2017-09-14

To determine whether circular RNAs (circRNAs) are involved in pathological processes of gastric cancer (GC). Three circRNAs with differential expression in GC and colorectal cancer were randomly selected for validation by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), using 20 pairs of gastric tissues and normal tissues. Based on the predicted circRNA-miRNA network, we then focused on hsa_circ_0000745, which was found to be down-regulated in 20 GC tissues compared with normal tissues. The hsa_circ_0000745 levels were further analyzed by qRT-PCR in 60 GC tissues and paired adjacent non-tumor tissues, as well as 60 plasma samples from GC patients and 60 plasma samples from healthy controls. The associations between the levels of hsa_circ_0000745 and the clinicopathological features of GC patients were statistically assessed. A receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of hsa_circ_0000745 in GC. Hsa_circ_0000745 was down-regulated in GC tissues vs non-tumorous tissues ( P < 0.001) and in plasma samples from patients with GC vs healthy controls ( P < 0.001). The expression level of hsa_circ_0000745 in GC tissues correlated with tumor differentiation, while the expression level in plasma correlated with tumor-node-metastasis stage. The area under the ROC curve (AUC) of hsa_circ_0000745 in plasma was 0.683, suggesting good diagnostic value. Plasma hsa_circ_0000745 level combined with carcinoembryogenic antigen (CEA) level increased the AUC to 0.775. Hsa_circ_0000745 plays an important role in GC and its expression level in plasma in combination with CEA level is a promising diagnostic marker for this malignancy.

Electron density measurements in STPX plasmas

NASA Astrophysics Data System (ADS)

Clark, Jerry; Williams, R.; Titus, J. B.; Mezonlin, E. D.; Akpovo, C.; Thomas, E.

2017-10-01

Diagnostics have been installed to measure the electron density of Spheromak Turbulent Physics Experiment (STPX) plasmas at Florida A. & M. University. An insertable probe, provided by Auburn University, consisting of a combination of a triple-tipped Langmuir probe and a radial array consisting of three ion saturation current / floating potential rings has been installed to measure instantaneous plasma density, temperature and plasma potential. As the ramp-up of the experimental program commences, initial electron density measurements from the triple-probe show that the electron density is on the order of 1019 particles/m3. For a passive measurement, a CO2 interferometer system has been designed and installed for measuring line-averaged densities and to corroborate the Langmuir measurements. We describe the design, calibration, and performance of these diagnostic systems on large volume STPX plasmas.

Quantifying Fusion Born Ion Populations in Magnetically Confined Plasmas using Ion Cyclotron Emission

DOE PAGES

Carbajal, L.; Warwick Univ., Coventry; Dendy, R. O.; ...

2017-03-07

Ion cyclotron emission (ICE) offers unique promise as a diagnostic of the fusion born alpha-particle population in magnetically confined plasmas. Pioneering observations from JET and TFTR found that ICE intensity P ICE scales approximately linearly with the measured neutron flux from fusion reactions, and with the inferred concentration, n /n i , of fusion-born alpha-particles confined within the plasma. We present fully nonlinear self-consistent kinetic simulations that reproduce this scaling for the first time. This resolves a longstanding question in the physics of fusion alpha particle confinement and stability in MCF plasmas. It confirms the MCI as the likely emissionmore » mechanism and greatly strengthens the basis for diagnostic exploitation of ICE in future burning plasmas.« less

Quantifying Fusion Born Ion Populations in Magnetically Confined Plasmas using Ion Cyclotron Emission

NASA Astrophysics Data System (ADS)

Carbajal, L.; Dendy, R. O.; Chapman, S. C.; Cook, J. W. S.

2017-03-01

Ion cyclotron emission (ICE) offers a unique promise as a diagnostic of the fusion born alpha-particle population in magnetically confined plasmas. Pioneering observations from JET and TFTR found that ICE intensity PICE scales approximately linearly with the measured neutron flux from fusion reactions, and with the inferred concentration, nα/ni, of fusion born alpha particles confined within the plasma. We present fully nonlinear self-consistent kinetic simulations that reproduce this scaling for the first time. This resolves a long-standing question in the physics of fusion alpha-particle confinement and stability in magnetic confinement fusion plasmas. It confirms the magnetoacoustic cyclotron instability as the likely emission mechanism and greatly strengthens the basis for diagnostic exploitation of ICE in future burning plasmas.

Diagnostic value of plasma morphology in patients with coronary heart disease

NASA Astrophysics Data System (ADS)

Malinova, Lidia I.; Sergeeva, Yuliya V.; Simonenko, Georgy V.; Tuchin, Valery V.; Denisova, Tatiana P.

2006-08-01

Blood plasma can be considered as a special water system with self-organization possibilities. Plasma slides as the results of wedge dehydration reflect its stereochemical interaction and their study can be used in diagnostic processes. 46 patients with coronary heart disease were studied. The main group was formed of men in age ranged from 54 to 72 years old with stable angina pectoris of II and III functional class (by Canadian classification) (n=25). The group of compare was of those who was hospitalized with diagnosis of acute coronary syndrome, men in age range 40-82. Clinical examination, basic biochemical tests and functional plasma morphology characteristics were studied. A number of qualitative and quantitative differences of blood plasma morphology of patients with chronic and acute coronary disease forms was revealed.

Quantifying Fusion Born Ion Populations in Magnetically Confined Plasmas using Ion Cyclotron Emission.

PubMed

Carbajal, L; Dendy, R O; Chapman, S C; Cook, J W S

2017-03-10

Ion cyclotron emission (ICE) offers a unique promise as a diagnostic of the fusion born alpha-particle population in magnetically confined plasmas. Pioneering observations from JET and TFTR found that ICE intensity P_{ICE} scales approximately linearly with the measured neutron flux from fusion reactions, and with the inferred concentration, n_{α}/n_{i}, of fusion born alpha particles confined within the plasma. We present fully nonlinear self-consistent kinetic simulations that reproduce this scaling for the first time. This resolves a long-standing question in the physics of fusion alpha-particle confinement and stability in magnetic confinement fusion plasmas. It confirms the magnetoacoustic cyclotron instability as the likely emission mechanism and greatly strengthens the basis for diagnostic exploitation of ICE in future burning plasmas.

The motional stark effect with laser-induced fluorescence diagnostic

NASA Astrophysics Data System (ADS)

Foley, E. L.; Levinton, F. M.

2010-05-01

The motional Stark effect (MSE) diagnostic is the worldwide standard technique for internal magnetic field pitch angle measurements in magnetized plasmas. Traditionally, it is based on using polarimetry to measure the polarization direction of light emitted from a hydrogenic species in a neutral beam. As the beam passes through the magnetized plasma at a high velocity, in its rest frame it perceives a Lorentz electric field. This field causes the H-alpha emission to be split and polarized. A new technique under development adds laser-induced fluorescence (LIF) to a diagnostic neutral beam (DNB) for an MSE measurement that will enable radially resolved magnetic field magnitude as well as pitch angle measurements in even low-field (<1 T) experiments. An MSE-LIF system will be installed on the National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Laboratory. It will enable reconstructions of the plasma pressure, q-profile and current as well as, in conjunction with the existing MSE system, measurements of radial electric fields.

Plasma plume diagnostics of low power stationary plasma thruster (SPT-20M8) with collisional radiative model

NASA Astrophysics Data System (ADS)

Uttamsing Rajput, Rajendrasing; Alona, Khaustova; Loyan, Andriy V.

2017-03-01

Electric propulsion offers higher specific impulse compared to the chemical propulsion systems. It reduces the overall propellant mass and enables high operational lifetimes. Scientific Technological Center of Space Power and Energy (STC SPE), KhAI is involved in designing, manufacturing and testing of stationary plasma thrusters (SPT). Efforts are made to perform plasma diagnostics with corona and collisional radiative models (C-R model), as expected corona model falls short below 4 eV because of the heavy particle collisions elimination, whereas the C-R model's applicability is confirmed. Several tests are performed to analyze the electron temperature at various operational parameters of thruster like discharge voltage and mass flow rate. SPT-20M8 far and near-field plumes diagnostics are performed. Feasibility of C-R model by comparing its result to optical emission spectroscopy (OES) to investigate the electron temperature is validated with the probe measurements within the 10% of discrepancy.

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

Carbajal, L.; Warwick Univ., Coventry; Dendy, R. O.

Ion cyclotron emission (ICE) offers unique promise as a diagnostic of the fusion born alpha-particle population in magnetically confined plasmas. Pioneering observations from JET and TFTR found that ICE intensity P ICE scales approximately linearly with the measured neutron flux from fusion reactions, and with the inferred concentration, n /n i , of fusion-born alpha-particles confined within the plasma. We present fully nonlinear self-consistent kinetic simulations that reproduce this scaling for the first time. This resolves a longstanding question in the physics of fusion alpha particle confinement and stability in MCF plasmas. It confirms the MCI as the likely emissionmore » mechanism and greatly strengthens the basis for diagnostic exploitation of ICE in future burning plasmas.« less

Development of High-Resolution UV-VIS Diagnostics for Space Plasma Simulation

NASA Astrophysics Data System (ADS)

Taylor, Andrew; Batishchev, Oleg

2012-10-01

Non-invasive far-UV-VIS plasma emission allows remote diagnostics of plasma, which is particularly important for space application. Accurate vacuum tank space plasma simulations require monochromators with high spectral resolution (better than 0.01A) to capture important details of atomic and ionic lines, such as Ly-alpha, etc. We are building a new system based on the previous work [1], and will discuss the development of a spectrometry system that combines a single-pass vacuum far-UV-NIR spectrometer and a tunable Fabry-Perot etalon. [4pt] [1] O. Batishchev and J.L. Cambier, Experimental Study of the Mini-Helicon Thruster, Air Force Research Laboratory Report, AFRL-RZ-ED-TR-2009-0020, 2009.

Measurements of the internal magnetic field using the B-Stark motional Stark effect diagnostic on DIII-D (inivited).

PubMed

Pablant, N A; Burrell, K H; Groebner, R J; Holcomb, C T; Kaplan, D H

2010-10-01

Results are presented from the B-Stark diagnostic installed on the DIII-D tokamak. This diagnostic provides measurements of the magnitude and direction of the internal magnetic field. The B-Stark system is a version of a motional Stark effect (MSE) diagnostic based on the relative line intensities and spacing of the Stark split D(α) emission from injected neutral beams. This technique may have advantages over MSE polarimetry based diagnostics in future devices, such as the ITER. The B-Stark diagnostic technique and calibration procedures are discussed. The system is shown to provide accurate measurements of B(θ)/B(T) and ∣B∣ over a range of plasma conditions. Measurements have been made with toroidal fields in the range of 1.2-2.1 T, plasma currents in the range 0.5-2.0 MA, densities between 1.7 and 9.0×10(19) m(-3), and neutral beam voltages between 50 and 81 keV. The viewing direction and polarization dependent transmission properties of the collection optics are found using an in situ beam into gas calibration. These results are compared to values found from plasma equilibrium reconstructions and the MSE polarimetry system on DIII-D.

Integration of process diagnostics and three dimensional simulations in thermal spraying

NASA Astrophysics Data System (ADS)

Zhang, Wei

Thermal spraying is a group of processes in which the metallic or ceramic materials are deposited in a molten or semi-molten state on a prepared substrate. In atmospheric plasma spray process, a thermal plasma jet is used to heat up and accelerate loading particles. The process is inherently complex due to the deviation from equilibrium conditions, three dimensional nature, multitude of interrelated variables involved, and stochastic variability at different stages. This dissertation is aimed at understanding the in-flight particle state and plasma plume characteristics in atmospheric plasma spray process through the integration of process diagnostics and three-dimensional simulation. Effects of injection angle and carrier gas flow rate on in-flight particle characteristics are studied experimentally and interpreted through numerical simulation. Plasma jet perturbation by particle injection angle, carrier gas, and particle loading are also identified. Maximum particle average temperature and velocity at any given spray distance is systematically quantified. Optimum plasma plume position for particle injection which was observed in experiments was verified numerically along with description of physical mechanisms. Correlation of spray distance with in-flight particle behavior for various kinds of materials is revealed. A new strategy for visualization and representation of particle diagnostic results for thermal spray processes has been presented. Specifically, 1 st order process maps (process-particle interactions) have been addressed by converting the Temperature-Velocity of particles obtained via diagnostics into non-dimensional group parameters [Melting Index-Reynolds number]. This approach provides an improved description of the thermal and kinetic energy of particles and allows for cross-comparison of diagnostic data within a given process for different materials, comparison of a single material across different thermal spray processes, and detailed assessment of the melting behavior through recourse to analysis of the distributions. An additional group parameter, Oxidation Index, has been applied to relatively track the oxidation extent of metallic particles under different operating conditions. The new mapping strategies have also been proposed in circumstances where only ensemble particle diagnostics are available. Through the integration of process diagnostics and numerical simulation, key issues concerning in-flight particle status as well as the controlling physical mechanisms have been analyzed. A scientific and intellectual strategy for universal description of particle characteristics has been successfully developed.

High power arcjet

NASA Technical Reports Server (NTRS)

Auweter-Kurtz, M.; Glocker, B.; Goelz, T. M.; Habiger, H.; Kurtz, H. L.; Schrade, H. O.; Wegmann, T.

1990-01-01

The activities on the development of the high power arc jet HIPARC, the thrust balance, and plasma diagnostic probes are discussed. Modifications of the HIPARC design and a synopsis of the materials used are given. Further experimental results with the TT30 thruster in the 50 kW range are presented. Some first calibration measurements of the thrust balance are also included. Progress concerning the development of plasma diagnostic devices is documented.

The application of high-speed photography in z-pinch high-temperature plasma diagnostics

NASA Astrophysics Data System (ADS)

Wang, Kui-lu; Qiu, Meng-tong; Hei, Dong-wei

2007-01-01

This invited paper is presented to discuss the application of high speed photography in z-pinch high temperature plasma diagnostics in recent years in Northwest Institute of Nuclear Technology in concentrative mode. The developments and applications of soft x-ray framing camera, soft x-ray curved crystal spectrometer, optical framing camera, ultraviolet four-frame framing camera and ultraviolet-visible spectrometer are introduced.

Plasma diagnostics of non-equilibrium atmospheric plasma jets

NASA Astrophysics Data System (ADS)

Shashurin, Alexey; Scott, David; Keidar, Michael; Shneider, Mikhail

2014-10-01

Intensive development and biomedical application of non-equilibrium atmospheric plasma jet (NEAPJ) facilitates rapid growth of the plasma medicine field. The NEAPJ facility utilized at the George Washington University (GWU) demonstrated efficacy for treatment of various cancer types (lung, bladder, breast, head, neck, brain and skin). In this work we review recent advances of the research conducted at GWU concerned with the development of NEAPJ diagnostics including Rayleigh Microwave Scattering setup, method of streamer scattering on DC potential, Rogowski coils, ICCD camera and optical emission spectroscopy. These tools allow conducting temporally-resolved measurements of plasma density, electrical potential, charge and size of the streamer head, electrical currents flowing though the jet, ionization front propagation speed etc. Transient dynamics of plasma and discharge parameters will be considered and physical processes involved in the discharge will be analyzed including streamer breakdown, electrical coupling of the streamer tip with discharge electrodes, factors determining NEAPJ length, cross-sectional shape and propagation path etc.

Interpretation of STS-3/plasma diagnostics package results in terms of large space structure plasma interactions

NASA Technical Reports Server (NTRS)

Kurth, W. S.

1984-01-01

The Plasma Diagnostics Package, which was flown aboard STS-3 recorded various chemical releases from the Orbiter. Changes in the plasma environment were observed to occur during Flash Evaporator System (FES) releases, water dumps and maneuvering thruster operations. During flash evaporator operations, broadband Orbiter-generated electro-static noise is enhanced and plasma density irregularity (delta n/N) is observed to increase by as much as 4 times and is strongly peaked below 6 Hz. In the case of water dumps, background electrostatic noise is enhanced or suppressed depending on frequency and Delta N/N is also seen to increase by as much as 4 times. Various changes in the plasma environment are effected by primary and vernier thruster operations. In addition, thruster activity stimulates electrostatic noise with a spectrum which is most intense at frequencies below 10 kHz.

The diagnostics of ultra-short pulse laser-produced plasma

NASA Astrophysics Data System (ADS)

Roth, Markus

2011-09-01

Since the invention of the laser, coherent light has been used to break down solid or gaseous material and transform it into a plasma. Over the last three decades two things have changed. Due to multiple advancements and design of high power lasers it is now possible to increase the electric and magnetic field strength that pushed the electron motion towards the regime of relativistic plasma physics. Moreover, due to the short pulse duration of the driving laser the underlying physics has become so transient that concepts like thermal equilibrium (even a local one) or spatial isotropy start to fail. Consequently short pulse laser-driven plasmas have become a rich source of new phenomena that we are just about beginning to explore. Such phenomena, like particle acceleration, nuclear laser-induced reactions, the generation of coherent secondary radiation ranging from THz to high harmonics and the production of attosecond pulses have excited an enormous interest in the study of short pulse laser plasmas. The diagnostics of such ultra-short pulse laser plasmas is a challenging task that involves many and different techniques compared to conventional laser-produced plasmas. While this review cannot cover the entire field of diagnostics that has been developed over the last years, we will try to give a summarizing description of the most important techniques that are currently being used.

Hypervelocity Dust Injection for Plasma Diagnostic Applications

NASA Astrophysics Data System (ADS)

Ticos, Catalin

2005-10-01

Hypervelocity micron-size dust grain injection was proposed for high-temperature magnetized plasma diagnosis. Multiple dust grains are launched simultaneously into high temperature plasmas at several km/s or more. The hypervelocity dust grains are ablated by the electron and ion fluxes. Fast imaging of the resulting luminous plumes attached to each grain is expected to yield local magnetic field vectors. Combination of multiple local magnetic field vectors reproduces 2D or even 3D maps of the internal magnetic field topology. Key features of HDI are: (1) a high spatial resolution, due to a relatively small transverse size of the elongated tail, and (2) a small perturbation level, as the dust grains introduce negligible number of particles compared to the plasma particle inventory. The latter advantage, however, could be seriously compromised if the gas load from the accelerator has an unobstructed access to the diagnosed plasma. Construction of a HDI diagnostic for National Spherical Torus Experiment (NSTX), which includes a coaxial plasma gun for dust grain acceleration, is underway. Hydrogen and deuterium gas discharges inside accelerator are created by a ˜ 1 mF capacitor bank pre-charged up to 10 kV. The diagnostic apparatus also comprises a dust dispenser for pre-loading the accelerator with dust grains, and an imaging system that has a high spatial and temporal resolution.

Plasma water as a diagnostic tool in the assessment of dehydration in children with acute gastroenteritis.

PubMed

Plaisier, Annemarie; Maingay-de Groof, Femke; Mast-Harwig, Roechama; Kalkman, Patricia M J; Wulkan, Remi W; Verwers, Renee; Neele, Marjolein; Hop, Wim C J; Groeneweg, Michael

2010-07-01

Acute gastroenteritis is common in childhood. The estimation of the degree of dehydration is essential for management of acute gastroenteritis. Plasma water was assessed as a diagnostic tool in children with acute gastroenteritis and dehydration admitted to hospital. In a prospective cohort study, 101 patients presenting at the emergency department with dehydration were included. Clinical assessment, routine laboratory tests, and plasma water measurement were performed. Plasma water was measured as a percentage of water content using dry weight method. During admission, patients were rehydrated in 12 h. Weight gain at the end of the rehydration period and 2 weeks thereafter was used to determine the percentage of weight loss as a gold standard for the severity of dehydration. Clinical assessment of dehydration was not significantly associated with the percentage of weight loss. Blood urea nitrogen (r = 0.3, p = 0.03), base excess (r =-0.31, p = 0.03), and serum bicarbonate (r = 0.32, p = 0.02) were significantly correlated with the percentage of weight loss. Plasma water did not correlate with the percentage of weight loss. On the basis of the presented data, plasma water should not be used as a diagnostic tool in the assessment of dehydration in children with acute gastroenteritis.

Spectroscopic studies of non-thermal plasma jet at atmospheric pressure formed in low-current nonsteady-state plasmatron for biomedical applications

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

Demkin, V. P.; Melnichuk, S. V.; Demkin, O. V.

The optical and electrophysical characteristics of the nonequilibrium low-temperature plasma formed by a low-current nonsteady-state plasmatron are experimentally investigated in the present work. It is demonstrated that experimental data on the optical diagnostics of the plasma jet can provide a basis for the construction of a self-consistent physical and mathematical plasma model and for the creation of plasma sources with controllable electrophysical parameters intended for the generation of the required concentration of active particles. Results of spectroscopic diagnostics of plasma of the low-current nonsteady-state plasmatron confirm that the given source is efficient for the generation of charged particles and short-wavelengthmore » radiation—important plasma components for biomedical problems of an increase in the efficiency of treatment of biological tissues by charged particles. Measurement of the spatial distribution of the plasma jet potential by the probe method has demonstrated that a negative space charge is formed in the plasma jet possibly due to the formation of electronegative oxygen ions.« less

Circulating metastasis associated in colon cancer 1 transcripts in gastric cancer patient plasma as diagnostic and prognostic biomarker

PubMed Central

Burock, Susen; Herrmann, Pia; Wendler, Ina; Niederstrasser, Markus; Wernecke, Klaus-Dieter; Stein, Ulrike

2015-01-01

AIM: To evaluate the diagnostic and prognostic value of circulating Metastasis Associated in Colon Cancer 1 (MACC1) transcripts in plasma of gastric cancer patients. METHODS: We provide for the first time a blood-based assay for transcript quantification of the metastasis inducer MACC1 in a prospective study of gastric cancer patient plasma. MACC1 is a strong prognostic biomarker for tumor progression and metastasis in a variety of solid cancers. We conducted a study to define the diagnostic and prognostic power of MACC1 transcripts using 76 plasma samples from gastric cancer patients, either newly diagnosed with gastric cancer, newly diagnosed with metachronous metastasis of gastric cancer, as well as follow-up patients. Findings were controlled by using plasma samples from 54 tumor-free volunteers. Plasma was separated, RNA was isolated, and levels of MACC1 as well as S100A4 transcripts were determined by quantitative RT-PCR. RESULTS: Based on the levels of circulating MACC1 transcripts in plasma we significantly discriminated tumor-free volunteers and gastric cancer patients (P < 0.001). Levels of circulating MACC1 transcripts were increased in gastric cancer patients of each disease stage, compared to tumor-free volunteers: patients with tumors without metastasis (P = 0.005), with synchronous metastasis (P = 0.002), with metachronous metastasis (P = 0.005), and patients during follow-up (P = 0.021). Sensitivity was 0.68 (95%CI: 0.45-0.85) and specificity was 0.89 (95%CI: 0.77-0.95), respectively. Importantly, gastric cancer patients with high circulating MACC1 transcript levels in plasma demonstrated significantly shorter survival when compared with patients demonstrating low MACC1 levels (P = 0.0015). Furthermore, gastric cancer patients with high circulating transcript levels of MACC1 as well as of S100A4 in plasma demonstrated significantly shorter survival when compared with patients demonstrating low levels of both biomarkers or with only one biomarker elevated (P = 0.001). CONCLUSION: Levels of circulating MACC1 transcripts in plasma of gastric cancer patients are of diagnostic value and are prognostic for patient survival in a prospective study. PMID:25574109

Physics in Europe--A Data File of Selected Research.

DTIC Science & Technology

1984-06-18

Negev Sapir Proc. 16th Euro. Conf. on Laser Interac. with Matter, London 26-30 Sept. 1983 1025 CPBICF laser plasma soft x-ray refractometry France...CPBICF laser plasma Schlieren diagnostic France 623 CPBICF laser plasma self focusing numerics UK 1025 CPBICF laser plasma soft x-ray refractometry

Additive Manufacture of Plasma Diagnostic Components Final Report Phase II

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

Woodruff, Simon; Romero-Talamas, Carlos; You, Setthivoine

There is now a well-established set of plasma diagnostics (see e.g. [3]), but these remain some of the mostexpensive assemblies in fusion systems since for every system they have to be custom built, and time fordiagnostic development can pace the project. Additive manufacturing (AM) has the potential to decreaseproduction cost and significantly lower design time of fusion diagnostic subsystems, which would realizesignificant cost reduction for standard diagnostics. In some cases, these basic components can be additivelymanufactured for less than 1/100th costs of conventional manufacturing.In our DOE Phase II SBIR, we examined the impact that AM can have on plasma diagnosticmore » cost bytaking 15 separate diagnostics through an engineering design using Conventional Manufacturing (CM) tech-niques, then optimizing the design to exploit the benefits of AM. The impact of AM techniques on cost isfound to be in several areas. First, the cost of materials falls because AM parts can be manufactured withlittle to no waste, and engineered to use less material than CM. Next, the cost of fabrication falls for AMparts relative to CM since the fabrication time can be computed exactly, and often no post-processing isrequired for the part to be functional. We find that AM techniques are well suited for plasma diagnosticssince typical diagnostic complexity comes at no additional cost. Cooling channels, for example, can be builtin to plasma-facing components at no extra cost. Fabrication costs associated with assembly are lower forAM parts because many components can be combined and printed as monoliths, thereby mitigating the needfor alignment or calibration. Finally, the cost of engineering is impacted by exploiting AM design tools thatallow standard components to be customized through web-interfaces. Furthermore, we find that conceptdesign costs can be impacted by scripting interfaces for online engineering design tools.« less

Comparative evaluation of neonatal bilirubin using Radiometer whole blood co-oximetry and plasma bilirubin methods from Roche Diagnostics and Ortho Clinical Diagnostics.

PubMed

Lano, Ian Marie; Lyon, Andrew W; Wang, Li; Ruskin, Rob; Lyon, Martha E

2018-03-01

Clinically significant variation has been reported within and between plasma and whole blood total bilirubin methods used to identify neonates for whom clinical intervention for hyperbilirubinemia may be required. To evaluate total bilirubin measurements between the Radiometer whole blood co-oximeter and plasma bilirubin methods from Roche Diagnostics and Ortho Clinical Diagnostics using neonatal specimens. Total bilirubin levels were analyzed by whole blood co-oximetry (Radiometer® ABL90). Specimens were centrifuged and plasma analyzed for total bilirubin with a diazo method (Roche Cobas® C-601) and a reflectance spectrophotometric BuBc dry film method (Ortho Clinical Diagnostics VITROS® 350). Results were evaluated by regression, Bland-Altman comparisons and t-tests. The patient correlation study yielded the following regression equations in μmol/L: a) Radiometer=1.03 Roche - 3.5μmol/L b) Radiometer=0.98 Ortho - 5.7μmol/L c) Roche=0.97 Ortho - 2.4μmol/L. The mean bias over the range of total bilirubin levels examined was -1.0μmol/L for the Radiometer versus the Roche (p≤0.305); -4.4μmol/L for the Radiometer versus Ortho (p≤0.005) and -4.4μmol/L for the Roche versus Ortho (p≤0.002). Whole blood total bilirubin measurement using the Radiometer ABL90 blood gas analyzer provides accurate and precise results compared to the Roche plasma diazo method. Compared to the reflectance spectrophotometric method, results are precise and had a small but statistically significant bias of -4.4μmol/L. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

The diagnostic value of long non-coding RNA MIR31HG and its role in esophageal squamous cell carcinoma.

PubMed

Sun, Kaiyan; Zhao, Xinwei; Wan, Junhu; Yang, Lijun; Chu, Jie; Dong, Shuling; Yin, Huiqing; Ming, Liang; He, Fucheng

2018-06-01

This study aimed to assess plasma lncRNA microRNA-31 hist gene (MIR31HG) as a novel diagnostic and therapeutic biomarker for esophageal squamous cell carcinoma (ESCC) and to investigate its role in ESCC. The expression of MIR31HG, Furin and MMP1 was examined via quantitative real-time polymerase chain reaction. MIR31HG expression between plasma and ESCC tissues was compared using Pearson correlation analysis; furthermore, the association between Furin/MMP1 levels and MIR31HG levels in ESCC tissues was analyzed. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of plasma MIR31HG. A WST-1 assay was performed to assess cell proliferation. The migratability and invasiveness of cells was determined via Transwell assays. MIR31HG was significantly upregulated in ESCC tissues and plasma (P < 0.01). A significant positive association was obtained between plasma and tissue MIR31HG expression in ESCC (r = 0.78, P < 0.01). Furthermore, MIR31HG displayed high diagnostic sensitivity and specificity for predicting ESCC occurance. Furthermore, knockdown of MIR31HG suppressed the capacity for proliferation, migration, and invasion of ESCC cells (P < 0.01). In addition, silencing of MIR31HG inhibited the expression of Furin and MMP1 in EC9706 and EC1 and the level of Furin/MMP1 in ESCC tissues displayed a significant positive correlation with MIR31HG (P < 0.01). MIR31HG can be used as a novel potential diagnostic biomarker and a potential therapeutic target for ESCC. Copyright © 2018 Elsevier Inc. All rights reserved.

Evidence cross-validation and Bayesian inference of MAST plasma equilibria

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

Nessi, G. T. von; Hole, M. J.; Svensson, J.

2012-01-15

In this paper, current profiles for plasma discharges on the mega-ampere spherical tokamak are directly calculated from pickup coil, flux loop, and motional-Stark effect observations via methods based in the statistical theory of Bayesian analysis. By representing toroidal plasma current as a series of axisymmetric current beams with rectangular cross-section and inferring the current for each one of these beams, flux-surface geometry and q-profiles are subsequently calculated by elementary application of Biot-Savart's law. The use of this plasma model in the context of Bayesian analysis was pioneered by Svensson and Werner on the joint-European tokamak [Svensson and Werner,Plasma Phys. Controlledmore » Fusion 50(8), 085002 (2008)]. In this framework, linear forward models are used to generate diagnostic predictions, and the probability distribution for the currents in the collection of plasma beams was subsequently calculated directly via application of Bayes' formula. In this work, we introduce a new diagnostic technique to identify and remove outlier observations associated with diagnostics falling out of calibration or suffering from an unidentified malfunction. These modifications enable a good agreement between Bayesian inference of the last-closed flux-surface with other corroborating data, such as that from force balance considerations using EFIT++[Appel et al., ''A unified approach to equilibrium reconstruction'' Proceedings of the 33rd EPS Conference on Plasma Physics (Rome, Italy, 2006)]. In addition, this analysis also yields errors on the plasma current profile and flux-surface geometry as well as directly predicting the Shafranov shift of the plasma core.« less

Neutral Beam Source and Target Plasma for Development of a Local Electric Field Fluctuation Diagnostic

NASA Astrophysics Data System (ADS)

Bakken, M. R.; Burke, M. G.; Fonck, R. J.; Lewicki, B. T.; Rhodes, A. T.; Winz, G. R.

2016-10-01

A new diagnostic measuring local E-> (r , t) fluctuations is being developed for plasma turbulence studies in tokamaks. This is accomplished by measuring fluctuations in the separation of the π components in the Hα motional Stark spectrum. Fluctuations in this separation are expected to be Ẽ / ẼEMSE 10-3EMSE 10-3 . In addition to a high throughput, high speed spectrometer, the project requires a low divergence (Ω 0 .5°) , 80 keV, 2.5 A H0 beam and a target plasma test stand. The beam employs a washer-stack arc ion source to achieve a high species fraction at full energy. Laboratory tests of the ion source demonstrate repeatable plasmas with Te 10 eV and ne 1.6 ×1017 m-3, sufficient for the beam ion optics requirements. Te and ne scalings of the ion source plasma are presented with respect to operational parameters. A novel three-phase resonant converter power supply will provide 6 mA/cm2 of 80 keV H0 at the focal plane for pulse lengths up to 15 ms, with low ripple δV / 80 keV 0.05 % at 280 kHz. Diagnostic development and validation tests will be performed on a magnetized plasma test stand with 0.5 T field. The test chamber will utilize a washer-stack arc source to produce a target plasma comparable to edge tokamak plasmas. A bias-plate with programmable power supply will be used to impose Ẽ within the target plasma. Work supported by US DOE Grant DE-FG02-89ER53296.

Diagnostics of Plasma Propulsion Devices

NASA Astrophysics Data System (ADS)

Cappelli, Mark A.

1998-11-01

Plasma rockets are rapidly emerging as critical technologies in future space flight. These devices take on various forms, ranging from electro-thermal to electromagnetic accelerators, generally categorized by the method in which electrical energy is converted to thrust. As is the case in many plasma devices, non-intrusive optical (emission, or laser-based) diagnostics is an essential element in the characterization of these plasma sources, as access to the discharges in these plasma engines is often limited. Furthermore, laser-based diagnostics offer additional benefits, including improved spatial resolution, and can provide state-specific measurements of species densities, velocities and energy distributions. In recent years, we have developed and applied a variety of emission and laser-based diagnostics strategies to the characterization of arcjet plasma and closed-drift xenon Hall plasma accelerators. Both of these types of plasma propulsion devices are of immediate interest to the space propulsion community, and are under varying stages of development. Arcjet thrusters have unique properties, with strong plasma density, temperature and velocity gradients, which enhance the coupling between the gasdynamic and plasma physics. Closed-drift Hall plasma thrusters are low density electrostatic devices that are inherently turbulent, and exhibit varying degrees of anomalous cross-field electron transport. Our most extensive, collective effort has been to apply laser-induced fluorescence, Doppler-free laser absorption, and Raman scattering to the characterization of hydrogen and helium arcjet flows. Detailed measurements of velocity, temperatures, and electron densities are compared to the results of magneto-hydrodynamic flowfield simulations. The results show that while the simulations capture many aspects of the flow, there are still some unresolved discrepancies. The database established for Hall thrusters is less extensive, as the laser absorption spectroscopy of xenon is somewhat more complicated due to the hyperfine and isotopic structure of electronic transitions. With an understanding of the spectroscopic absorption lineshape for two select transitions in neutral and ionized xenon, we have successfully mapped out the neutral and singly ionized xenon velocities in the acceleration zone of Hall thrusters. These results indicate that the acceleration zone in a short-channel thruster is outside of the device, consistent with the measurements of plasma potential using more conventional Langmuir electrostatic probes. The spectroscopic data has also been used to identify limitations in ground-test facilities.

Flight Plasma Diagnostics for High-Power, Solar-Electric Deep-Space Spacecraft

NASA Technical Reports Server (NTRS)

Johnson, Lee; De Soria-Santacruz Pich, Maria; Conroy, David; Lobbia, Robert; Huang, Wensheng; Choi, Maria; Sekerak, Michael J.

2018-01-01

NASA's Asteroid Redirect Robotic Mission (ARRM) project plans included a set of plasma and space environment instruments, the Plasma Diagnostic Package (PDP), to fulfill ARRM requirements for technology extensibility to future missions. The PDP objectives were divided into the classes of 1) Plasma thruster dynamics, 2) Solar array-specific environmental effects, 3) Plasma environmental spacecraft effects, and 4) Energetic particle spacecraft environment. A reference design approach and interface requirements for ARRM's PDP was generated by the PDP team at JPL and GRC. The reference design consisted of redundant single-string avionics located on the ARRM spacecraft bus as well as solar array, driving and processing signals from multiple copies of several types of plasma, effects, and environments sensors distributed over the spacecraft and array. The reference design sensor types were derived in part from sensors previously developed for USAF Research Laboratory (AFRL) plasma effects campaigns such as those aboard TacSat-2 in 2007 and AEHF-2 in 2012.

Application of Dynamic Logic Algorithm to Inverse Scattering Problems Related to Plasma Diagnostics

NASA Astrophysics Data System (ADS)

Perlovsky, L.; Deming, R. W.; Sotnikov, V.

2010-11-01

In plasma diagnostics scattering of electromagnetic waves is widely used for identification of density and wave field perturbations. In the present work we use a powerful mathematical approach, dynamic logic (DL), to identify the spectra of scattered electromagnetic (EM) waves produced by the interaction of the incident EM wave with a Langmuir soliton in the presence of noise. The problem is especially difficult since the spectral amplitudes of the noise pattern are comparable with the amplitudes of the scattered waves. In the past DL has been applied to a number of complex problems in artificial intelligence, pattern recognition, and signal processing, resulting in revolutionary improvements. Here we demonstrate its application to plasma diagnostic problems. [4pt] Perlovsky, L.I., 2001. Neural Networks and Intellect: using model-based concepts. Oxford University Press, New York, NY.

Quantum Cascade Laser Absorption Spectroscopy as a Plasma Diagnostic Tool: An Overview

PubMed Central

Welzel, Stefan; Hempel, Frank; Hübner, Marko; Lang, Norbert; Davies, Paul B.; Röpcke, Jürgen

2010-01-01

The recent availability of thermoelectrically cooled pulsed and continuous wave quantum and inter-band cascade lasers in the mid-infrared spectral region has led to significant improvements and new developments in chemical sensing techniques using in-situ laser absorption spectroscopy for plasma diagnostic purposes. The aim of this article is therefore two-fold: (i) to summarize the challenges which arise in the application of quantum cascade lasers in such environments, and, (ii) to provide an overview of recent spectroscopic results (encompassing cavity enhanced methods) obtained in different kinds of plasma used in both research and industry. PMID:22163581

Dynamics of blood plasma by spectropolarimetry and biochemical techniques

NASA Astrophysics Data System (ADS)

Voloshynska, Katerina; Ilashchuka, Tetjana; Prydij, Olexander; Gruia, Maria

2014-08-01

The aim of the study was to establish objective parameters of the field of laser and incoherent radiation of different spectral ranges (UV, visible, IR) as a non-invasive optical method of interaction with different samples of biological tissues and fluids of patients to determine the dynamics of metabolic syndrome and choosing the best personal treatment. As diagnostic methods have been used ultraviolet spectrometry samples of blood plasma in the liquid state, infrared spectroscopy middle range (2,5 - 25 microns) dry residue of plasma polarization and laser diagnostic technique of thin histological sections of biological tissues.

Spectropolarimetry of blood plasma in optimal molecular targeted therapy

NASA Astrophysics Data System (ADS)

Voloshynska, Katerina; Ilashchuk, Tetjana; Yermolenko, Sergey

2015-02-01

The aim of the study was to establish objective parameters of the field of laser and incoherent radiation of different spectral ranges (UV, visible, IR) as a non-invasive optical method of interaction with different samples of biological tissues and fluids of patients to determine the dynamics of metabolic syndrome and choosing the best personal treatment. As diagnostic methods have been used ultraviolet spectrometry samples of blood plasma in the liquid state, infrared spectroscopy middle range (2,5 - 25 microns) dry residue of plasma polarization and laser diagnostic technique of thin histological sections of biological tissues.

The degree of mutual anisotropy of biological liquids polycrystalline nets as a parameter in diagnostics and differentiations of hominal inflammatory processes

NASA Astrophysics Data System (ADS)

Angelsky, O. V.; Ushenko, Yu. A.; Balanetska, V. O.

2011-09-01

To characterize the degree of consistency of parameters of the optically uniaxial birefringent protein nets of blood plasma a new parameter - complex degree of mutual anisotropy is suggested. The technique of polarization measuring the coordinate distributions of the complex degree of mutual anisotropy of blood plasma is developed. It is shown that statistic approach to the analysis of the complex degree of mutual anisotropy distributions of blood plasma is effective during the diagnostics and differentiation of an acute inflammatory processes as well as acute and gangrenous appendicitis.

Quantum cascade laser absorption spectroscopy as a plasma diagnostic tool: an overview.

PubMed

Welzel, Stefan; Hempel, Frank; Hübner, Marko; Lang, Norbert; Davies, Paul B; Röpcke, Jürgen

2010-01-01

The recent availability of thermoelectrically cooled pulsed and continuous wave quantum and inter-band cascade lasers in the mid-infrared spectral region has led to significant improvements and new developments in chemical sensing techniques using in-situ laser absorption spectroscopy for plasma diagnostic purposes. The aim of this article is therefore two-fold: (i) to summarize the challenges which arise in the application of quantum cascade lasers in such environments, and, (ii) to provide an overview of recent spectroscopic results (encompassing cavity enhanced methods) obtained in different kinds of plasma used in both research and industry.

An accurate automated technique for quasi-optics measurement of the microwave diagnostics for fusion plasma

NASA Astrophysics Data System (ADS)

Hu, Jianqiang; Liu, Ahdi; Zhou, Chu; Zhang, Xiaohui; Wang, Mingyuan; Zhang, Jin; Feng, Xi; Li, Hong; Xie, Jinlin; Liu, Wandong; Yu, Changxuan

2017-08-01

A new integrated technique for fast and accurate measurement of the quasi-optics, especially for the microwave/millimeter wave diagnostic systems of fusion plasma, has been developed. Using the LabVIEW-based comprehensive scanning system, we can realize not only automatic but also fast and accurate measurement, which will help to eliminate the effects of temperature drift and standing wave/multi-reflection. With the Matlab-based asymmetric two-dimensional Gaussian fitting method, all the desired parameters of the microwave beam can be obtained. This technique can be used in the design and testing of microwave diagnostic systems such as reflectometers and the electron cyclotron emission imaging diagnostic systems of the Experimental Advanced Superconducting Tokamak.

Multi-dimensional optical and laser-based diagnostics of low-temperature ionized plasma discharges

DOE PAGES

Barnat, Edward V.

2011-09-15

In this paper, a review of work centered on the utilization of multi-dimensional optical diagnostics to study phenomena arising in radiofrequency plasma discharges is given. The diagnostics range from passive techniques such as optical emission to more active techniques utilizing nanosecond lasers capable of both high temporal and spatial resolution. In this review, emphasis is placed on observations that would have been more difficult, if not impossible, to make without the use of such diagnostic techniques. Examples include the sheath structure around an electrode consisting of two different metals, double layers that arise in magnetized hydrogen discharges, or a largemore » region of depleted argon 1s 4 levels around a biased probe in an rf discharge.« less

CONFERENCE REPORT: Summary of the 16th IAEA Technical Meeting on 'Research using Small Fusion Devices'

NASA Astrophysics Data System (ADS)

Gribkov, V.; Van Oost, G.; Malaquias, A.; Herrera, J.

2006-10-01

Common research topics that are being studied in small, medium and large devices such as H-mode like or improved confinement, turbulence and transport are reported. These included modelling and diagnostic developments for edge and core, to characterize plasma density, temperature, electric potential, plasma flows, turbulence scale, etc. Innovative diagnostic methods were designed and implemented which could be used to develop experiments in small devices (in some cases not possible in large devices due to higher power deposition) to allow a better understanding of plasma edge and core properties. Reports are given addressing research in linear devices that can be used to study particular plasma physics topics relevant for other magnetic confinement devices such as the radial transport and the modelling of self-organized plasma jets involved in spheromak-like plasma formation. Some aspects of the work presented are of interest to the astrophysics community since they are believed to shed light on the basis of the physics of stellar jets. On the dense magnetized plasmas (DMP) topic, the present status of research, operation of new devices, plasma dynamics modelling and diagnostic developments is reported. The main devices presented belong to the class of Z-pinches, mostly plasma foci, and several papers were presented under this topic. The physics of DMP is important both for the main-stream fusion investigations as well as for providing the basis for elaboration of new concepts. New high-current technology introduced in the DMP devices design and construction make these devices nowadays more reliably fitted to various applications and give the possibility to widen the energy range used by them in both directions—to the multi-MJ level facilities and down to miniature plasma focus devices with energy of just a few J.

Analysis of staged Z-pinch implosion trajectories from experiments on Zebra

NASA Astrophysics Data System (ADS)

Ross, Mike P.; Conti, F.; Darling, T. W.; Ruskov, E.; Valenzuela, J.; Wessel, F. J.; Beg, F.; Narkis, J.; Rahman, H. U.

2017-10-01

The Staged Z-pinch plasma confinement concept relies on compressing an annular liner of high-Z plasma onto a target plasma column of deuterium fuel. The interface between the liner and target is stable against the Magneto-Rayleigh-Taylor Instability, which leads to effective fuel compression and makes the concept interesting as a potential fusion reactor. The liner initiates as a neutral gas puff, while the target plasma is a partially ionized (Zeff < 10 percent column ejected from a coaxial plasma gun. The Zebra pulsed power generator (1 MA peak current, 100 ns rise time) provides the discharge that ionizes the liner and drives the Z-pinch implosion. Diverse diagnostics observe the 100-300 km/s implosions including silicon diodes, photo-conducting detectors (PCDs), laser shadowgraphy, an XUV framing camera, and a visible streak camera. The imaging diagnostics track instabilities smaller than 0.1 mm, and Z-pinch diameters below 2.5 mm are seen at peak compression. This poster correlates the data from these diagnostics to elucidate implosion behavior dependencies on liner gas, liner pressure, target pressure, and applied, axial-magnetic field. Funded by the Advanced Research Projects Agency - Energy, DE-AR0000569.

Development of Simple Designs of Multitip Probe Diagnostic Systems for RF Plasma Characterization

PubMed Central

Naz, M. Y.; Shukrullah, S.; Ghaffar, A.; Rehman, N. U.

2014-01-01

Multitip probes are very useful diagnostics for analyzing and controlling the physical phenomena occurring in low temperature discharge plasmas. However, DC biased probes often fail to perform well in processing plasmas. The objective of the work was to deduce simple designs of DC biased multitip probes for parametric study of radio frequency plasmas. For this purpose, symmetric double probe, asymmetric double probe, and symmetric triple probe diagnostic systems and their driving circuits were designed and tested in an inductively coupled plasma (ICP) generated by a 13.56 MHz radio frequency (RF) source. Using I-V characteristics of these probes, electron temperature, electron number density, and ion saturation current was measured as a function of input power and filling gas pressure. An increasing trend was noticed in electron temperature and electron number density for increasing input RF power whilst a decreasing trend was evident in these parameters when measured against filling gas pressure. In addition, the electron energy probability function (EEPF) was also studied by using an asymmetric double probe. These studies confirmed the non-Maxwellian nature of the EEPF and the presence of two groups of the energetic electrons at low filling gas pressures. PMID:24683326

High density plasmas and new diagnostics: An overview (invited).

PubMed

Celona, L; Gammino, S; Mascali, D

2016-02-01

One of the limiting factors for the full understanding of Electron Cyclotron Resonance Ion Sources (ECRISs) fundamental mechanisms consists of few types of diagnostic tools so far available for such compact machines. Microwave-to-plasma coupling optimisation, new methods of density overboost provided by plasma wave generation, and magnetostatic field tailoring for generating a proper electron energy distribution function, suitable for optimal ion beams formation, require diagnostic tools spanning across the entire electromagnetic spectrum from microwave interferometry to X-ray spectroscopy; these methods are going to be implemented including high resolution and spatially resolved X-ray spectroscopy made by quasi-optical methods (pin-hole cameras). The ion confinement optimisation also requires a complete control of cold electrons displacement, which can be performed by optical emission spectroscopy. Several diagnostic tools have been recently developed at INFN-LNS, including "volume-integrated" X-ray spectroscopy in low energy domain (2-30 keV, by using silicon drift detectors) or high energy regime (>30 keV, by using high purity germanium detectors). For the direct detection of the spatially resolved spectral distribution of X-rays produced by the electronic motion, a "pin-hole camera" has been developed also taking profit from previous experiences in the ECRIS field. The paper will give an overview of INFN-LNS strategy in terms of new microwave-to-plasma coupling schemes and advanced diagnostics supporting the design of new ion sources and for optimizing the performances of the existing ones, with the goal of a microwave-absorption oriented design of future machines.

Non-axisymmetric equilibrium reconstruction of a current-carrying stellarator using external magnetic and soft x-ray inversion radius measurements

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

Ma, X., E-mail: xzm0005@auburn.edu; Maurer, D. A.; Knowlton, S. F.

2015-12-15

Non-axisymmetric free-boundary equilibrium reconstructions of stellarator plasmas are performed for discharges in which the magnetic configuration is strongly modified by ohmically driven plasma current. These studies were performed on the compact toroidal hybrid device using the V3FIT reconstruction code with a set of 50 magnetic diagnostics external to the plasma. With the assumption of closed magnetic flux surfaces, the reconstructions using external magnetic measurements allow accurate estimates of the net toroidal flux within the last closed flux surface, the edge safety factor, and the plasma shape of these highly non-axisymmetric plasmas. The inversion radius of standard sawteeth is used tomore » infer the current profile near the magnetic axis; with external magnetic diagnostics alone, the current density profile is imprecisely reconstructed.« less

Non-axisymmetric equilibrium reconstruction of a current-carrying stellarator using external magnetic and soft x-ray inversion radius measurements

NASA Astrophysics Data System (ADS)

Ma, X.; Maurer, D. A.; Knowlton, S. F.; ArchMiller, M. C.; Cianciosa, M. R.; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Hebert, J. D.; Herfindal, J. L.; Pandya, M. D.; Roberds, N. A.; Traverso, P. J.

2015-12-01

Non-axisymmetric free-boundary equilibrium reconstructions of stellarator plasmas are performed for discharges in which the magnetic configuration is strongly modified by ohmically driven plasma current. These studies were performed on the compact toroidal hybrid device using the V3FIT reconstruction code with a set of 50 magnetic diagnostics external to the plasma. With the assumption of closed magnetic flux surfaces, the reconstructions using external magnetic measurements allow accurate estimates of the net toroidal flux within the last closed flux surface, the edge safety factor, and the plasma shape of these highly non-axisymmetric plasmas. The inversion radius of standard sawteeth is used to infer the current profile near the magnetic axis; with external magnetic diagnostics alone, the current density profile is imprecisely reconstructed.

Transport properties of plasmas in microwave electrothermal thrusters. Master's thesis

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

Haraburda, S.S.

1990-01-01

The microwave electrothermal thruster is a potential propulsion system for spacecraft applications such as platform station keeping. It is a thruster which allows no contact between the electrodes and the propellant. For this thruster, the electromagnetic energy is transferred to the electrons in the plasma region of the propellant using the TM011 and TM012 modes of a microwave cavity system. The collisional processes by the electrons with the propellant causes transfer of the energy. Work was done to study these processes using several diagnostic techniques - calorimetry, photography, and spectroscopy. Experimental results of these techniques for nitrogen and helium gasesmore » are included. These diagnostic techniques are important in understanding plasma phenomena and designing practical plasma rocket thrusters. In addition, a broad theoretical background is included to provide a fundamental description of the plasma phenomena.« less

1 μs broadband frequency sweeping reflectometry for plasma density and fluctuation profile measurements

NASA Astrophysics Data System (ADS)

Clairet, F.; Bottereau, C.; Medvedeva, A.; Molina, D.; Conway, G. D.; Silva, A.; Stroth, U.; ASDEX Upgrade Team; Tore Supra Team; Eurofusion Mst1 Team

2017-11-01

Frequency swept reflectometry has reached the symbolic value of 1 μs sweeping time; this performance has been made possible, thanks to an improved control of the ramp voltage driving the frequency source. In parallel, the memory depth of the acquisition system has been upgraded and can provide up to 200 000 signals during a plasma discharge. Additional improvements regarding the trigger delay determination of the acquisition and the voltage ramp linearity required by this ultra-fast technique have been set. While this diagnostic is traditionally dedicated to the plasma electron density profile measurement, such a fast sweeping rate can provide the study of fast plasma events and turbulence with unprecedented time and radial resolution from the edge to the core. Experimental results obtained on ASDEX Upgrade plasmas are presented to demonstrate the performances of the diagnostic.

Non-axisymmetric equilibrium reconstruction of a current-carrying stellarator using external magnetic and soft x-ray inversion radius measurements

DOE PAGES

Ma, X.; Maurer, D. A.; Knowlton, Stephen F.; ...

2015-12-22

Non-axisymmetric free-boundary equilibrium reconstructions of stellarator plasmas are performed for discharges in which the magnetic configuration is strongly modified by ohmically driven plasma current. These studies were performed on the compact toroidal hybrid device using the V3FIT reconstruction code with a set of 50 magnetic diagnostics external to the plasma. With the assumption of closed magnetic flux surfaces, the reconstructions using external magnetic measurements allow accurate estimates of the net toroidal flux within the last closed flux surface, the edge safety factor, and the plasma shape of these highly non-axisymmetric plasmas. Lastly, the inversion radius of standard saw-teeth is usedmore » to infer the current profile near the magnetic axis; with external magnetic diagnostics alone, the current density profile is imprecisely reconstructed.« less

Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited).

PubMed

Krychowiak, M; Adnan, A; Alonso, A; Andreeva, T; Baldzuhn, J; Barbui, T; Beurskens, M; Biel, W; Biedermann, C; Blackwell, B D; Bosch, H S; Bozhenkov, S; Brakel, R; Bräuer, T; Brotas de Carvalho, B; Burhenn, R; Buttenschön, B; Cappa, A; Cseh, G; Czarnecka, A; Dinklage, A; Drews, P; Dzikowicka, A; Effenberg, F; Endler, M; Erckmann, V; Estrada, T; Ford, O; Fornal, T; Frerichs, H; Fuchert, G; Geiger, J; Grulke, O; Harris, J H; Hartfuß, H J; Hartmann, D; Hathiramani, D; Hirsch, M; Höfel, U; Jabłoński, S; Jakubowski, M W; Kaczmarczyk, J; Klinger, T; Klose, S; Knauer, J; Kocsis, G; König, R; Kornejew, P; Krämer-Flecken, A; Krawczyk, N; Kremeyer, T; Książek, I; Kubkowska, M; Langenberg, A; Laqua, H P; Laux, M; Lazerson, S; Liang, Y; Liu, S C; Lorenz, A; Marchuk, A O; Marsen, S; Moncada, V; Naujoks, D; Neilson, H; Neubauer, O; Neuner, U; Niemann, H; Oosterbeek, J W; Otte, M; Pablant, N; Pasch, E; Sunn Pedersen, T; Pisano, F; Rahbarnia, K; Ryć, L; Schmitz, O; Schmuck, S; Schneider, W; Schröder, T; Schuhmacher, H; Schweer, B; Standley, B; Stange, T; Stephey, L; Svensson, J; Szabolics, T; Szepesi, T; Thomsen, H; Travere, J-M; Trimino Mora, H; Tsuchiya, H; Weir, G M; Wenzel, U; Werner, A; Wiegel, B; Windisch, T; Wolf, R; Wurden, G A; Zhang, D; Zimbal, A; Zoletnik, S

2016-11-01

Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. An overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.

Ion source research and development at University of Jyväskylä: Studies of different plasma processes and towards the higher beam intensities.

PubMed

Koivisto, H; Kalvas, T; Tarvainen, O; Komppula, J; Laulainen, J; Kronholm, R; Ranttila, K; Tuunanen, J; Thuillier, T; Xie, D; Machicoane, G

2016-02-01

Several ion source related research and development projects are in progress at the Department of Physics, University of Jyväskylä (JYFL). The work can be divided into investigation of the ion source plasma and development of ion sources, ion beams, and diagnostics. The investigation covers the Electron Cyclotron Resonance Ion Source (ECRIS) plasma instabilities, vacuum ultraviolet (VUV) and visible light emission, photon induced electron emission, and the development of plasma diagnostics. The ion source development covers the work performed for radiofrequency-driven negative ion source, RADIS, beam line upgrade of the JYFL 14 GHz ECRIS, and the development of a new room-temperature-magnet 18 GHz ECRIS, HIISI.

Preliminary design of laser-induced breakdown spectroscopy for proto-Material Plasma Exposure eXperiment

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

Shaw, G., E-mail: shawgc@ornl.gov; University of Tennessee, Knoxville, Tennessee 37996; Martin, M. Z.

2014-11-15

Laser-induced breakdown spectroscopy (LIBS) is a technique for measuring surface matter composition. LIBS is performed by focusing laser radiation onto a target surface, ablating the surface, forming a plasma, and analyzing the light produced. LIBS surface analysis is a possible diagnostic for characterizing plasma-facing materials in ITER. Oak Ridge National Laboratory has enabled the initial installation of a laser-induced breakdown spectroscopy diagnostic on the prototype Material-Plasma Exposure eXperiment (Proto-MPEX), which strives to mimic the conditions found at the surface of the ITER divertor. This paper will discuss the LIBS implementation on Proto-MPEX, preliminary design of the fiber optic LIBS collectionmore » probe, and the expected results.« less

Can we estimate plasma density in ICP driver through electrical parameters in RF circuit?

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

Bandyopadhyay, M., E-mail: mainak@iter-india.org; Sudhir, Dass, E-mail: dass.sudhir@iter-india.org; Chakraborty, A., E-mail: arunkc@iter-india.org

2015-04-08

To avoid regular maintenance, invasive plasma diagnostics with probes are not included in the inductively coupled plasma (ICP) based ITER Neutral Beam (NB) source design. Even non-invasive probes like optical emission spectroscopic diagnostics are also not included in the present ITER NB design due to overall system design and interface issues. As a result, negative ion beam current through the extraction system in the ITER NB negative ion source is the only measurement which indicates plasma condition inside the ion source. However, beam current not only depends on the plasma condition near the extraction region but also on the perveancemore » condition of the ion extractor system and negative ion stripping. Nevertheless, inductively coupled plasma production region (RF driver region) is placed at distance (∼ 30cm) from the extraction region. Due to that, some uncertainties are expected to be involved if one tries to link beam current with plasma properties inside the RF driver. Plasma characterization in source RF driver region is utmost necessary to maintain the optimum condition for source operation. In this paper, a method of plasma density estimation is described, based on density dependent plasma load calculation.« less

Improving spatial and spectral resolution of TCV Thomson scattering

NASA Astrophysics Data System (ADS)

Hawke, J.; Andrebe, Y.; Bertizzolo, R.; Blanchard, P.; Chavan, R.; Decker, J.; Duval, B.; Lavanchy, P.; Llobet, X.; Marlétaz, B.; Marmillod, P.; Pochon, G.; Toussaint, M.

2017-12-01

The recently completed MST2 upgrade to the Thomson scattering (TS) system on TCV (Tokamak à Configuration Variable) at the Swiss Plasma Center aims to provide an enhanced spatial and spectral resolution while maintaining the high level of diagnostic flexibility for the study of TCV plasmas. The MST2 (Medium Sized Tokamak) is a work program within the Eurofusion ITER physics department, aimed at exploiting Europe's medium sized tokamak programs for a better understanding of ITER physics. This upgrade to the TCV Thomson scattering system involved the installation of 40 new compact 5-channel spectrometers and modifications to the diagnostics fiber optic design. The complete redesign of the fiber optic backplane incorporates fewer larger diameter fibers, allowing for a higher resolution in both the core and edge of TCV plasmas along the laser line, with a slight decrease in the signal to noise ratio of Thomson measurements. The 40 new spectrometers added to the system are designed to cover the full range of temperatures expected in TCV, able to measure electron temperatures (Te) with high precision between (6 eV and 20 keV) . The design of these compact spectrometers stems originally from the design utilized in the MAST (Mega Amp Spherical Tokamak) TS system located in Oxfordshire, United Kingdom. This design was implemented on TCV with an overall layout of optical fibers and spectrometers to achieve an overall increase in the spatial resolution, specifically a resolution of approximately 1% of the minor radius within the plasma pedestal region. These spectrometers also enhance the diagnostic spectral resolution, especially within the plasma edge, due to the low Te measurement capabilities. These additional spectrometers allow for a much greater diagnostic flexibility, allowing for quality full Thomson profiles in 75% of TCV plasma configurations.

Overview of diagnostic implementation on Proto-MPEX at ORNL

NASA Astrophysics Data System (ADS)

Biewer, T. M.; Bigelow, T.; Caughman, J. B. O.; Fehling, D.; Goulding, R. H.; Gray, T. K.; Isler, R. C.; Martin, E. H.; Meitner, S.; Rapp, J.; Unterberg, E. A.; Dhaliwal, R. S.; Donovan, D.; Kafle, N.; Ray, H.; Shaw, G. C.; Showers, M.; Mosby, R.; Skeen, C.

2015-11-01

The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) recently began operating with an expanded diagnostic set. Approximately 100 sightlines have been established, delivering the plasma light emission to a ``patch panel'' in the diagnostic room for distribution to a variety of instruments: narrow-band filter spectroscopy, Doppler spectroscopy, laser induced breakdown spectroscopy, optical emission spectroscopy, and Thomson scattering. Additional diagnostic systems include: IR camera imaging, in-vessel thermocouples, ex-vessel fluoroptic probes, fast pressure gauges, visible camera imaging, microwave interferometry, a retarding-field energy analyzer, rf-compensated and ``double'' Langmuir probes, and B-dot probes. A data collection and archival system has been initiated using the MDSplus format. This effort capitalizes on a combination of new and legacy diagnostic hardware at ORNL and was accomplished largely through student labor. This work was supported by the US. D.O.E. contract DE-AC05-00OR22725.

The Set of Diagnostics for the First Operation Campaign of the Wendelstein 7-X Stellarator

NASA Astrophysics Data System (ADS)

König, Ralf; Baldzuhn, J.; Biel, W.; Biedermann, C.; Bosch, H. S.; Bozhenkov, S.; Bräuer, T.; Brotas de Carvalho, B.; Burhenn, R.; Buttenschön, B.; Cseh, G.; Czarnecka, A.; Endler, M.; Erckmann, V.; Estrada, T.; Geiger, J.; Grulke, O.; Hartmann, D.; Hathiramani, D.; Hirsch, M.; Jabłonski, S.; Jakubowski, M.; Kaczmarczyk, J.; Klinger, T.; Klose, S.; Kocsis, G.; Kornejew, P.; Krämer-Flecken, A.; Kremeyer, T.; Krychowiak, M.; Kubkowska, M.; Langenberg, A.; Laqua, H. P.; Laux, M.; Liang, Y.; Lorenz, A.; Marchuk, A. O.; Moncada, V.; Neubauer, O.; Neuner, U.; Oosterbeek, J. W.; Otte, M.; Pablant, N.; Pasch, E.; Pedersen, T. S.; Rahbarnia, K.; Ryc, L.; Schmitz, O.; Schneider, W.; Schuhmacher, H.; Schweer, B.; Stange, T.; Thomsen, H.; Travere, J.-M.; Szepesi, T.; Wenzel, U.; Werner, A.; Wiegel, B.; Windisch, T.; Wolf, R.; Wurden, G. A.; Zhang, D.; Zimbal, A.; Zoletnik, S.; the W7-X Team

2015-10-01

Wendelstein 7-X (W7-X) is a large optimized stellarator (B=2.5T, V=30m3) aiming at demonstrating the reactor relevance of the optimized stellarators. In 2015 W7-X will begin its first operation phase (OP1.1) with five inertially cooled inboard limiters made of graphite. Assuming the heat loads can be spread out evenly between the limiters, 1 second discharges at 2 MW of ECRH heating power could be run in OP1.1. The expected plasma parameters will be sufficient to demonstrate the readiness of the installed diagnostics and even to run a first physics program. The diagnostics available for this first operation phase, including some special limiter diagnostics, and their capabilities are being presented. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

2D imaging X-ray diagnostic for measuring the current density distribution in a wide-area electron beam produced in a multiaperture diode with plasma cathode

NASA Astrophysics Data System (ADS)

Kurkuchekov, V.; Kandaurov, I.; Trunev, Y.

2018-05-01

A simple and inexpensive X-ray diagnostic tool was designed for measuring the cross-sectional current density distribution in a low-relativistic pulsed electron beam produced in a source based on an arc-discharge plasma cathode and multiaperture diode-type electron optical system. The beam parameters were as follows: Uacc = 50–110 kV, Ibeam = 20–100 A, τbeam = 0.1–0.3 ms. The beam effective diameter was ca. 7 cm. Based on a pinhole camera, the diagnostic allows one to obtain a 2D profile of electron beam flux distribution on a flat metal target in a single shot. The linearity of the diagnostic system response to the electron flux density was established experimentally. Spatial resolution of the diagnostic was also estimated in special test experiments. The optimal choice of the main components of the diagnostic technique is discussed.

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

Feder, Russell; Youssef, Mahamoud; Klabacha, Jonathan

USITER is one of seven partner domestic agencies (DA) contributing components to the ITER project. Four diagnostic port plug packages (two equatorial ports and two upper ports) will be engineered and fabricated by Princeton Plasma Physics Lab (PPPL). Diagnostic port plugs as illustrated in Fig. 1 are large primarily stainless steel structures that serve several roles on ITER. The port plugs are the primary vacuum seal and tritium confinement barriers for the vessel. The port plugs also house several plasma diagnostic systems and other machine service equipment. Finally, each port plug must shield high energy neutrons and gamma photons frommore » escaping and creating radiological problems in maintenance areas behind the port plugs. The optimization of the balance between adequate shielding and the need for high performance, high throughput diagnostics systems is the focus of this paper. Neutronics calculations are also needed for assessing nuclear heating and nuclear damage in the port plug and diagnostic components. Attila, the commercially available discrete-ordinates software package, is used for all diagnostic port plug neutronics analysis studies at PPPL.« less

Size-based molecular diagnostics using plasma DNA for noninvasive prenatal testing.

PubMed

Yu, Stephanie C Y; Chan, K C Allen; Zheng, Yama W L; Jiang, Peiyong; Liao, Gary J W; Sun, Hao; Akolekar, Ranjit; Leung, Tak Y; Go, Attie T J I; van Vugt, John M G; Minekawa, Ryoko; Oudejans, Cees B M; Nicolaides, Kypros H; Chiu, Rossa W K; Lo, Y M Dennis

2014-06-10

Noninvasive prenatal testing using fetal DNA in maternal plasma is an actively researched area. The current generation of tests using massively parallel sequencing is based on counting plasma DNA sequences originating from different genomic regions. In this study, we explored a different approach that is based on the use of DNA fragment size as a diagnostic parameter. This approach is dependent on the fact that circulating fetal DNA molecules are generally shorter than the corresponding maternal DNA molecules. First, we performed plasma DNA size analysis using paired-end massively parallel sequencing and microchip-based capillary electrophoresis. We demonstrated that the fetal DNA fraction in maternal plasma could be deduced from the overall size distribution of maternal plasma DNA. The fetal DNA fraction is a critical parameter affecting the accuracy of noninvasive prenatal testing using maternal plasma DNA. Second, we showed that fetal chromosomal aneuploidy could be detected by observing an aberrant proportion of short fragments from an aneuploid chromosome in the paired-end sequencing data. Using this approach, we detected fetal trisomy 21 and trisomy 18 with 100% sensitivity (T21: 36/36; T18: 27/27) and 100% specificity (non-T21: 88/88; non-T18: 97/97). For trisomy 13, the sensitivity and specificity were 95.2% (20/21) and 99% (102/103), respectively. For monosomy X, the sensitivity and specificity were both 100% (10/10 and 8/8). Thus, this study establishes the principle of size-based molecular diagnostics using plasma DNA. This approach has potential applications beyond noninvasive prenatal testing to areas such as oncology and transplantation monitoring.

Size-based molecular diagnostics using plasma DNA for noninvasive prenatal testing

PubMed Central

Yu, Stephanie C. Y.; Chan, K. C. Allen; Zheng, Yama W. L.; Jiang, Peiyong; Liao, Gary J. W.; Sun, Hao; Akolekar, Ranjit; Leung, Tak Y.; Go, Attie T. J. I.; van Vugt, John M. G.; Minekawa, Ryoko; Oudejans, Cees B. M.; Nicolaides, Kypros H.; Chiu, Rossa W. K.; Lo, Y. M. Dennis

2014-01-01

Noninvasive prenatal testing using fetal DNA in maternal plasma is an actively researched area. The current generation of tests using massively parallel sequencing is based on counting plasma DNA sequences originating from different genomic regions. In this study, we explored a different approach that is based on the use of DNA fragment size as a diagnostic parameter. This approach is dependent on the fact that circulating fetal DNA molecules are generally shorter than the corresponding maternal DNA molecules. First, we performed plasma DNA size analysis using paired-end massively parallel sequencing and microchip-based capillary electrophoresis. We demonstrated that the fetal DNA fraction in maternal plasma could be deduced from the overall size distribution of maternal plasma DNA. The fetal DNA fraction is a critical parameter affecting the accuracy of noninvasive prenatal testing using maternal plasma DNA. Second, we showed that fetal chromosomal aneuploidy could be detected by observing an aberrant proportion of short fragments from an aneuploid chromosome in the paired-end sequencing data. Using this approach, we detected fetal trisomy 21 and trisomy 18 with 100% sensitivity (T21: 36/36; T18: 27/27) and 100% specificity (non-T21: 88/88; non-T18: 97/97). For trisomy 13, the sensitivity and specificity were 95.2% (20/21) and 99% (102/103), respectively. For monosomy X, the sensitivity and specificity were both 100% (10/10 and 8/8). Thus, this study establishes the principle of size-based molecular diagnostics using plasma DNA. This approach has potential applications beyond noninvasive prenatal testing to areas such as oncology and transplantation monitoring. PMID:24843150

Plasma endotoxin activity in kangaroos with oral necrobacillosis (lumpy jaw disease) using an automated handheld testing system

PubMed Central

SOTOHIRA, Yukari; SUZUKI, Kazuyuki; SASAKI, Haruka; SANO, Tadashi; TSUCHIYA, Masakazu; SUZUKI, Yohko; SHIMAMORI, Toshio; TSUKANO, Kenji; SATO, Ayano; YOKOTA, Hiroshi; ASAKAWA, Mitsuhiko

2016-01-01

The aim of the present study was to evaluate the reliability and effectiveness of directly determining endotoxin activity in plasma samples from kangaroos with lumpy jaw disease (LJD, n=15) and healthy controls (n=12). Prior to the present study, the ability of the commercially available automated handheld portable test system (PTSTM) to detect endotoxin activity in kangaroo plasma was compared with that of the traditional LAL-kinetic turbidimetric (KT) assay. Plasma samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTSTM was not significantly different from that of the traditional LAL-based assay. The data obtained using PTSTM correlated with those using KT (r2=0.963, P<0.001). These findings indicated that the PTSTM is applicable as a simplified system to assess endotoxin activity in macropods. In the present study, we demonstrated the diagnostic value of plasma endotoxin activity in kangaroos with systemic inflammation caused by oral necrobacillosis and identified plasma endotoxin activity as a sensitive marker of systemic inflammation in kangaroos with LJD. Based on ROC curves, we proposed a diagnostic cut-off point for endotoxin activity of >0.22 EU/ml for the identification of LJD. Our results indicate that the assessment of plasma endotoxin activity is a promising diagnostic tool for determining the outcome of LJD in captive macropods. PMID:26902804

Plasma endotoxin activity in kangaroos with oral necrobacillosis (lumpy jaw disease) using an automated handheld testing system.

PubMed

Sotohira, Yukari; Suzuki, Kazuyuki; Sasaki, Haruka; Sano, Tadashi; Tsuchiya, Masakazu; Suzuki, Yohko; Shimamori, Toshio; Tsukano, Kenji; Sato, Ayano; Yokota, Hiroshi; Asakawa, Mitsuhiko

2016-07-01

The aim of the present study was to evaluate the reliability and effectiveness of directly determining endotoxin activity in plasma samples from kangaroos with lumpy jaw disease (LJD, n=15) and healthy controls (n=12). Prior to the present study, the ability of the commercially available automated handheld portable test system (PTS(TM)) to detect endotoxin activity in kangaroo plasma was compared with that of the traditional LAL-kinetic turbidimetric (KT) assay. Plasma samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTS(TM) was not significantly different from that of the traditional LAL-based assay. The data obtained using PTS(TM) correlated with those using KT (r(2)=0.963, P<0.001). These findings indicated that the PTS(TM) is applicable as a simplified system to assess endotoxin activity in macropods. In the present study, we demonstrated the diagnostic value of plasma endotoxin activity in kangaroos with systemic inflammation caused by oral necrobacillosis and identified plasma endotoxin activity as a sensitive marker of systemic inflammation in kangaroos with LJD. Based on ROC curves, we proposed a diagnostic cut-off point for endotoxin activity of >0.22 EU/ml for the identification of LJD. Our results indicate that the assessment of plasma endotoxin activity is a promising diagnostic tool for determining the outcome of LJD in captive macropods.

Investigation of Singly Ionized Iodine Spectroscopy in Support of Electrostatic Propulsion Diagnostics Development

DTIC Science & Technology

2012-07-02

from complex user interactions due to the use of liquid lasing medium with finite lifetime. Solid state lasers such as titanium sapphire (Ti:Sapphire...transitions for laser -induced fluorescence of an accelerated atomic iodine singly charged ion (I+). While the second spectrum of iodine has been analyzed...diagnostics tools, such as laser -induced fluorescence (LIF), to examine the plasma acceleration within an electro-static plasma propulsion thruster. While

Remote network control plasma diagnostic system for Tokamak T-10

NASA Astrophysics Data System (ADS)

Troynov, V. I.; Zimin, A. M.; Krupin, V. A.; Notkin, G. E.; Nurgaliev, M. R.

2016-09-01

The parameters of molecular plasma in closed magnetic trap is studied in this paper. Using the system of molecular diagnostics, which was designed by the authors on the «Tokamak T-10» facility, the radiation of hydrogen isotopes at the plasma edge is investigated. The scheme of optical radiation registration within visible spectrum is described. For visualization, identification and processing of registered molecular spectra a new software is developed using MatLab environment. The software also includes electronic atlas of electronic-vibrational-rotational transitions for molecules of protium and deuterium. To register radiation from limiter cross-section a network control system is designed using the means of the Internet/Intranet. Remote control system diagram and methods are given. The examples of web-interfaces for working out equipment control scenarios and viewing of results are provided. After test run in Intranet, the remote diagnostic system will be accessible through Internet.

Progress On The Thomson Scattering Diagnostic For The Helicon Plasma Experiment (HPX)

NASA Astrophysics Data System (ADS)

Green, A.; Emami, T.; Davies, R.; Frank, J.; Hopson, J.; Karama, J.; James, R. W.; Hopson, J.; Paolino, R. N.; Sandri, E.; Turk, J.; Wicke, M.; Cgapl Team

2017-10-01

A high-performance spectrometer utilizing volume-phase-holographic (VPH) grating and a charge coupled device (CCD) camera with a range of 380-1090 nm and resolution of 1024x1024 has been assembled on HPX at the Coast Guard Academy Plasma Laboratory (CGAPL). This spectrometer will collect doppler shifted photons, emitted from the plasma by the first harmonic (1064 nm) of a 2.5 J Nd:YAG laser. Direct measurements of the plasma's temperature and density will be determined using HPX's Thomson Scattering (TS) single spatial point diagnostic system. A zero order half wave plate rotates the polarization of the second harmonic TS laser beam when operating at a wavelength of 532 nm. A linear actuated periscope has been constructed to remotely redirect the beam so that 532 and 1064 nm wavelengths can both be used. TS has the capability of determining plasma properties on short time scales and will be used to create a robust picture of the internal plasma parameters. Operating at both 532 and 1064 nm results in a self-consistent measurement and better use our existing spectrometer and soon to be constructed polychrometer. A prototype spectrometer has been constructed to explore the Andor CCD camera's resolution and sensitivity. The current status of the diagnostic development, spectrometer, and collection optics system will be reported. Supported by U.S. DEPS Grant [HEL-JTO] PRWJFY17.

A synthetic diagnostic for beam emission spectroscopy in the helically symmetric experiment stellarator

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

Dobbins, T. J., E-mail: tdobbins@wisc.edu; Kumar, S. T. A.; Anderson, D. T.

The Helically Symmetric Experiment (HSX) has a number of active spectroscopy diagnostics. Due to the relatively large beam width compared to the plasma minor radius, it is difficult to achieve good spatial resolution at the core of the HSX plasma. This is due to the fact that the optical sightline cuts through many flux surfaces with varying field vectors within the beam. In order to compare the experimental results with theoretical models it is important to accurately model the beam width effects. A synthetic diagnostic has been developed for this purpose. This synthetic diagnostic calculates the effect of spot sizemore » and beam width on the measurements of quantities of interest, including radial electric field, flow velocity, and Stark polarization.« less

A synthetic diagnostic for beam emission spectroscopy in the helically symmetric experiment stellarator

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

Dobbins, T. J.; Kumar, S. T. A.; Anderson, D. T.

The Helically Symmetric Experiment (HSX) has a number of active spectroscopy diagnostics. Due to the relatively large beam width compared to the plasma minor radius, it is difficult to achieve good spatial resolution at the core of the HSX plasma. This is due to the fact that the optical sightline cuts through many flux surfaces with varying field vectors within the beam. It is important to accurately model the beam width effects in order to compare the experimental results with theoretical models. We've developed a synthetic diagnostic for this purpose. This synthetic diagnostic calculates the effect of spot size andmore » beam width on the measurements of quantities of interest, including radial electric field, flow velocity, and Stark polarization.« less

A synthetic diagnostic for beam emission spectroscopy in the helically symmetric experiment stellarator

DOE PAGES

Dobbins, T. J.; Kumar, S. T. A.; Anderson, D. T.

2016-08-03

The Helically Symmetric Experiment (HSX) has a number of active spectroscopy diagnostics. Due to the relatively large beam width compared to the plasma minor radius, it is difficult to achieve good spatial resolution at the core of the HSX plasma. This is due to the fact that the optical sightline cuts through many flux surfaces with varying field vectors within the beam. It is important to accurately model the beam width effects in order to compare the experimental results with theoretical models. We've developed a synthetic diagnostic for this purpose. This synthetic diagnostic calculates the effect of spot size andmore » beam width on the measurements of quantities of interest, including radial electric field, flow velocity, and Stark polarization.« less

Dust dynamics and diagnostic applications in quasi-neutral plasmas and magnetic fusion

NASA Astrophysics Data System (ADS)

Wang, Zhehui; Ticos, Catalin M.; Si, Jiahe; Delzanno, Gian Luca; Lapenta, Gianni; Wurden, Glen

2007-11-01

Little is known about dust dynamics in highly ionized quasi-neutral plasmas with ca. 1.0 e+20 per cubic meter density and ion temperature at a few eV and above, including in magnetic fusion. For example, dust motion in fusion, better known as UFO's, has been observed since 1980's but not explained. Solid understanding of dust dynamics is also important to International Thermonuclear Experimental Reactor (ITER) because of concerns about safety and dust contamination of fusion core. Compared with well studied strongly-coupled dusty plasma regime, new physics may arise in the higher density quasi-neutral plasma regime because of at least four orders of magnitude higher density and two orders of magnitude hotter ion temperature. Our recent laboratory experiments showed that plasma-flow drag force dominates over other forces in a quasi-neutral flowing plasma. In contrast, delicate balance among different forces in dusty plasma has led to many unique phenomena, in particular, the formation of dust crystal. Based on our experiments, we argue that 1) dust crystal will not form in the highly ionized plasmas with flows; 2) the UFO's are moving dust dragged by plasma flows; 3) dust can be used to measure plasma flow. Two diagnostic applications using dust for laboratory quasi-neutral plasmas and magnetic fusion will also be presented.

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

Koivisto, H., E-mail: hannu.koivisto@phys.jyu.fi; Kalvas, T.; Tarvainen, O.

Several ion source related research and development projects are in progress at the Department of Physics, University of Jyväskylä (JYFL). The work can be divided into investigation of the ion source plasma and development of ion sources, ion beams, and diagnostics. The investigation covers the Electron Cyclotron Resonance Ion Source (ECRIS) plasma instabilities, vacuum ultraviolet (VUV) and visible light emission, photon induced electron emission, and the development of plasma diagnostics. The ion source development covers the work performed for radiofrequency-driven negative ion source, RADIS, beam line upgrade of the JYFL 14 GHz ECRIS, and the development of a new room-temperature-magnetmore » 18 GHz ECRIS, HIISI.« less

Betatron radiation based diagnostics for plasma wakefield accelerated electron beams at the SPARC_LAB test facility

NASA Astrophysics Data System (ADS)

Shpakov, V.; Anania, M. P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Curcio, A.; Dabagov, S.; Ferrario, M.; Filippi, F.; Marocchino, A.; Paroli, B.; Pompili, R.; Rossi, A. R.; Zigler, A.

2016-09-01

Recent progress with wake-field acceleration has shown a great potential in providing high gradient acceleration fields, while the quality of the beams remains relatively poor. Precise knowledge of the beam size at the exit from the plasma and matching conditions for the externally injected beams are the key for improvement of beam quality. Betatron radiation emitted by the beam during acceleration in the plasma is a powerful tool for the transverse beam size measurement, being also non-intercepting. In this work we report on the technical solutions chosen at SPARC_LAB for such diagnostics tool, along with expected parameters of betatron radiation.

Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

NASA Astrophysics Data System (ADS)

Brombin, M.; Spolaore, M.; Serianni, G.; Pomaro, N.; Taliercio, C.; Palma, M. Dalla; Pasqualotto, R.; Schiesko, L.

2014-11-01

A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors' holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from Radio Frequency plasma) experiment: tests in BATMAN (BAvarian Test Machine for Negative ions).

PubMed

Brombin, M; Spolaore, M; Serianni, G; Pomaro, N; Taliercio, C; Dalla Palma, M; Pasqualotto, R; Schiesko, L

2014-11-01

A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors' holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

Generation of disc-like plasma from laser-matter interaction in the presence of a strong external magnetic field

NASA Astrophysics Data System (ADS)

Ivanov, V. V.; Maximov, A. V.; Betti, R.; Wiewior, P. P.; Hakel, P.; Sherrill, M. E.

2017-08-01

Dynamics of laser produced plasma in a strong magnetic field was studied using a 1 MA pulsed power generator coupled to an intense, high-energy laser. A 2-2.5 MG magnetic field was generated on the surface of a rod load 0.8-1.2 mm in diameter. A sub-nanosecond laser pulse with intensity of 3 × 1015 W cm-2 was focused on the rod load surface. Side-on laser diagnostics showed the generation of two collimated jets 1-3 mm long on the front and rear sides of the load. End-on laser diagnostics reveal that the laser produced plasma in the MG magnetic field takes the form of a thin disc as the plasma propagates along the magnetic field lines. The disc-like plasma expands radially across the magnetic field with a velocity of 250 km s-1. An electron temperature of 400 eV was measured in the laser-produced plasma on the rod load.

Compact, accurate description of diagnostic neutral beam propagation and attenuation in a high temperature plasma for charge exchange recombination spectroscopy analysis.

PubMed

Bespamyatnov, Igor O; Rowan, William L; Granetz, Robert S

2008-10-01

Charge exchange recombination spectroscopy on Alcator C-Mod relies on the use of the diagnostic neutral beam injector as a source of neutral particles which penetrate deep into the plasma. It employs the emission resulting from the interaction of the beam atoms with fully ionized impurity ions. To interpret the emission from a given point in the plasma as the density of emitting impurity ions, the density of beam atoms must be known. Here, an analysis of beam propagation is described which yields the beam density profile throughout the beam trajectory from the neutral beam injector to the core of the plasma. The analysis includes the effects of beam formation, attenuation in the neutral gas surrounding the plasma, and attenuation in the plasma. In the course of this work, a numerical simulation and an analytical approximation for beam divergence are developed. The description is made sufficiently compact to yield accurate results in a time consistent with between-shot analysis.

Comprehensive Study of Plasma-Wall Sheath Transport Phenomena

DTIC Science & Technology

2012-09-10

environment, a Langmuir probe and a Retarding Potential Analyzer (RPA). The Langmuir probe could be considered the seminal plasma diagnostic, and a large...plasma-sheath interface. Electric field is normalized by Te/LD (LD is the Debye length) and velocity is normalized by the Bohm speed. Figure 14...studying the interaction of the near-wall plasma sheath with a magnetic field , and modeled the plasma sheath of the GT thick-sheath (~10mm) plasma

Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)—Patient Version

Cancer.gov

Plasma cell neoplasms occur when abnormal plasma cells or myeloma cells form tumors in the bones or soft tissues of the body. Multiple myeloma, plasmacytoma, lymphoplasmacytic lymphoma, and monoclonal gammopathy of undetermined significance (MGUS) are different types of plasma cell neoplasms. Find out about risk factors, symptoms, diagnostic tests, prognosis, and treatment for these diseases.

A novel ABCD1 mutation detected by next generation sequencing in presumed hereditary spastic paraplegia: A 30-year diagnostic delay caused by misleading biochemical findings.

PubMed

Koutsis, Georgios; Lynch, David S; Tucci, Arianna; Houlden, Henry; Karadima, Georgia; Panas, Marios

2015-08-15

To present a Greek family in which 5 male and 2 female members developed progressive spastic paraplegia. Plasma very long chain fatty acids (VLCFA) were reportedly normal at first testing in an affected male and for over 30 years the presumed diagnosis was hereditary spastic paraplegia (HSP). Targeted next generation sequencing (NGS) was used as a further diagnostic tool. Targeted exome sequencing in the proband, followed by Sanger sequencing confirmation; mutation segregation testing in multiple family members and plasma VLCFA measurement in the proband. NGS of the proband revealed a novel frameshift mutation in ABCD1 (c.1174_1178del, p.Leu392Serfs*7), bringing an end to diagnostic uncertainty by establishing the diagnosis of adrenomyeloneuropathy (AMN), the myelopathic phenotype of X-linked adrenoleukodystrophy (ALD). The mutation segregated in all family members and the diagnosis of AMN/ALD was confirmed by plasma VLCFA measurement. Confounding factors that delayed the diagnosis are presented. This report highlights the diagnostic utility of NGS in patients with undiagnosed spastic paraplegia, establishing a molecular diagnosis of AMN, allowing proper genetic counseling and management, and overcoming the diagnostic delay that can be rarely caused by false negative VLCFA analysis. Copyright © 2015 Elsevier B.V. All rights reserved.

Feasibility, strategy, methodology, and analysis of probe measurements in plasma under high gas pressure

NASA Astrophysics Data System (ADS)

Demidov, V. I.; Koepke, M. E.; Kurlyandskaya, I. P.; Malkov, M. A.

2018-02-01

This paper reviews existing theories for interpreting probe measurements of electron distribution functions (EDF) at high gas pressure when collisions of electrons with atoms and/or molecules near the probe are pervasive. An explanation of whether or not the measurements are realizable and reliable, an enumeration of the most common sources of measurement error, and an outline of proper probe-experiment design elements that inherently limit or avoid error is presented. Additionally, we describe recent expanded plasma-condition compatibility for EDF measurement, including in applications of large wall probe plasma diagnostics. This summary of the authors’ experiences gained over decades of practicing and developing probe diagnostics is intended to inform, guide, suggest, and detail the advantages and disadvantages of probe application in plasma research.

Effect of Energetic Plasma Flux on Flowing Liquid Lithium Surfaces

NASA Astrophysics Data System (ADS)

Kalathiparambil, Kishor; Jung, Soonwook; Christenson, Michael; Fiflis, Peter; Xu, Wenyu; Szott, Mathew; Ruzic, David

2014-10-01

An operational liquid lithium system with steady state flow driven by thermo-electric magneto-hydrodynamic force and capable of constantly refreshing the plasma exposed surface have been demonstrated at U of I. To evaluate the system performance in reactor relevant conditions, specifically to understand the effect of disruptive plasma events on the performance of the liquid metal PFCs, the setup was integrated to a pulsed plasma generator. A coaxial plasma generator drives the plasma towards a theta pinch which preferentially heats the ions, simulating ELM like flux, and the plasma is further guided towards the target chamber which houses the flowing lithium system. The effect of the incident flux is examined using diagnostic tools including triple Langmuir probe, calorimeter, rogowski coils, Ion energy analyzers, and fast frame spectral image acquisition with specific optical filters. The plasma have been well characterized and a density of ~1021 m-3, with electron temperature ~10 - 20 eV is measured, and final plasma velocities of 34 - 74 kms-1 have been observed. Calorimetric measurements using planar molybdenum targets indicate a maximum plasma energy (with 6 kV plasma gun and 20 kV theta pinch) of 0.08 MJm-2 with plasma divergence effects resulting in marginal reduction of 40 +/- 23 J in plasma energy. Further results from the other diagnostic tools, using the flowing lithium targets and the planar targets coated with lithium will be presented. DOE DE-SC0008587.

Design advances of the Core Plasma Thomson Scattering diagnostic for ITER

NASA Astrophysics Data System (ADS)

Scannell, R.; Maslov, M.; Naylor, G.; O'Gorman, T.; Kempenaars, M.; Carr, M.; Bilkova, P.; Bohm, P.; Giudicotti, L.; Pasqualotto, R.; Bassan, M.; Vayakis, G.; Walsh, M.; Huxford, R.

2017-11-01

The Core Plasma Thomson Scattering (CPTS) diagnostic on ITER performs measurements of the electron temperature and density profiles which are critical to the understanding of the ITER plasma. The diagnostic must satisfy the ITER project requirements, which translate to requirements on performance as well as reliability, safety and engineering. The implications are particularly challenging for beam dump lifetime, the need for continuous active alignment of the diagnostic during operation, allowable neutron flux in the interspace and the protection of the first mirror from plasma deposition. The CPTS design has been evolving over a number of years. One recent improvement is that the collection optics have been modified to include freeform surfaces. These freeform surfaces introduce extra complexity to the manufacturing but provide greater flexibility in the design. The greater flexibility introduced allows for example to lower neutron throughput or use fewer surfaces while improving optical performance. Performance assessment has shown that scattering from a 1064 nm laser will be sufficient to meet the measurement requirements, at least for the system at the start of operations. Optical transmission at λ < 600 nm is expected to degrade over the ITER lifetime due to fibre darkening and deposition on the first mirror. For this reason, it is proposed that the diagnostic should additionally include measurements of TS 'depolarised light' and a 1319 nm laser system. These additional techniques have different spectral and polarisation dependencies compared to scattering from a 1064 nm laser and hence provide greater robustness into the inferred measurements of Te and ne in the core.

Plasma free metanephrines in healthy cats, cats with non-adrenal disease and a cat with suspected phaeochromocytoma.

PubMed

Wimpole, Justin A; Adagra, Carl F M; Billson, Mark F; Pillai, Dilo N; Foster, Darren J

2010-06-01

Phaeochromocytomas are catecholamine-secreting tumours of the adrenal glands and are rare in cats. Plasma metanephrine levels are widely considered the diagnostic test of choice for phaeochromocytoma in people but have not been investigated in cats. In this study plasma free normetanephrine and metanephrine levels were measured using high-pressure liquid chromatography in healthy cats, sick cats with non-adrenal disease and in a cat with a suspected phaeochromocytoma. Plasma normetanephrine was significantly higher in sick cats with non-adrenal disease compared to healthy cats (P<0.05) and markedly higher in the cat with a suspected phaeochromocytoma when compared to either group. Plasma metanephrine was not significantly different in any of the groups. This study establishes a first-line guide reference range for plasma metanephrine and normetanephrine levels in healthy cats and cats with non-adrenal disease. These results provide rationale for further studies to establish the use of plasma normetanephrine levels as a potential diagnostic test for phaeochromocytoma in the cat. Copyright 2009 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.

Diagnostics of recombining laser plasma parameters based on He-like ion resonance lines intensity ratios

NASA Astrophysics Data System (ADS)

Ryazantsev, S. N.; Skobelev, I. Yu; Faenov, A. Ya; Pikuz, T. A.; Grum-Grzhimailo, A. N.; Pikuz, S. A.

2016-11-01

While the plasma created by powerful laser expands from the target surface it becomes overcooled, i.e. recombining one. Improving of diagnostic methods applicable for such plasma is rather important problem in laboratory astrophysics nowadays because laser produced jets are fully scalable to young stellar objects. Such scaling is possible because of the plasma hydrodynamic equations invariance under some transformations. In this paper it is shown that relative intensities of the resonance transitions in He-like ions can be used to measure the parameters of recombining plasma. Intensity of the spectral lines corresponding to these transitions is sensitive to the density in the range of 1016-1020 cm-3 while the temperature ranges from 10 to 100 eV for ions with nuclear charge Zn ∼ 10. Calculations were carried out for F VIII ion and allowed to determine parameters of plasma jets created by nanosecond laser system ELFIE (Ecole Polytechnique, France) for astrophysical phenomenon modelling. Obtained dependencies are quite universal and can be used for any recombining plasma containing He-like fluorine ions.

In situ measurement of plasma and shock wave properties inside laser-drilled metal holes

NASA Astrophysics Data System (ADS)

Brajdic, Mihael; Hermans, Martin; Horn, Alexander; Kelbassa, Ingomar

2008-10-01

High-speed imaging of shock wave and plasma dynamics is a commonly used diagnostic method for monitoring processes during laser material treatment. It is used for processes such as laser ablation, cutting, keyhole welding and drilling. Diagnosis of laser drilling is typically adopted above the material surface because lateral process monitoring with optical diagnostic methods inside the laser-drilled hole is not possible due to the hole walls. A novel method is presented to investigate plasma and shock wave properties during the laser drilling inside a confined environment such as a laser-drilled hole. With a novel sample preparation and the use of high-speed imaging combined with spectroscopy, a time and spatial resolved monitoring of plasma and shock wave dynamics is realized. Optical emission of plasma and shock waves during drilling of stainless steel with ns-pulsed laser radiation is monitored and analysed. Spatial distributions and velocities of shock waves and of plasma are determined inside the holes. Spectroscopy is accomplished during the expansion of the plasma inside the drilled hole allowing for the determination of electron densities.

Power accounting of plasma discharges in the linear device Proto-MPEX

NASA Astrophysics Data System (ADS)

Showers, M.; Piotrowicz, P. A.; Beers, C. J.; Biewer, T. M.; Caneses, J.; Canik, J.; Caughman, J. B. O.; Donovan, D. C.; Goulding, R. H.; Lumsdaine, A.; Kafle, N.; Owen, L. W.; Rapp, J.; Ray, H.

2018-06-01

Plasma material interaction (PMI) studies are crucial to the successful development of future fusion reactors. Prototype Material Plasma Exposure eXperiment (Proto-MPEX) is a prototype design for the MPEX, a steady-state linear device being developed to study PMI. The primary purpose of Proto-MPEX is developing the plasma heating source concepts for MPEX. A power accounting study of Proto-MPEX works to identify machine operating parameters that could improve its performance, thereby increasing its PMI research capabilities, potentially impacting the MPEX design concept. To build a comprehensive power balance, an analysis of the helicon region has been performed implementing a diagnostic suite and software modeling to identify mechanisms and locations of heat loss from the main plasma. Of the 106.3 kW of input power, up to 90.5% of the power has been accounted for in the helicon region. When the analysis was extended to encompass the device to its end plates, 49.2% of the input power was accounted for and verified diagnostically. Areas requiring further diagnostic analysis are identified. The required improvements will be implemented in future work. The data acquisition and analysis processes will be streamlined to form a working model for future power balance studies of Proto-MPEX. ).

Energetic particle instabilities in fusion plasmas

NASA Astrophysics Data System (ADS)

Sharapov, S. E.; Alper, B.; Berk, H. L.; Borba, D. N.; Breizman, B. N.; Challis, C. D.; Classen, I. G. J.; Edlund, E. M.; Eriksson, J.; Fasoli, A.; Fredrickson, E. D.; Fu, G. Y.; Garcia-Munoz, M.; Gassner, T.; Ghantous, K.; Goloborodko, V.; Gorelenkov, N. N.; Gryaznevich, M. P.; Hacquin, S.; Heidbrink, W. W.; Hellesen, C.; Kiptily, V. G.; Kramer, G. J.; Lauber, P.; Lilley, M. K.; Lisak, M.; Nabais, F.; Nazikian, R.; Nyqvist, R.; Osakabe, M.; Perez von Thun, C.; Pinches, S. D.; Podesta, M.; Porkolab, M.; Shinohara, K.; Schoepf, K.; Todo, Y.; Toi, K.; Van Zeeland, M. A.; Voitsekhovich, I.; White, R. B.; Yavorskij, V.; TG, ITPA EP; Contributors, JET-EFDA

2013-10-01

Remarkable progress has been made in diagnosing energetic particle instabilities on present-day machines and in establishing a theoretical framework for describing them. This overview describes the much improved diagnostics of Alfvén instabilities and modelling tools developed world-wide, and discusses progress in interpreting the observed phenomena. A multi-machine comparison is presented giving information on the performance of both diagnostics and modelling tools for different plasma conditions outlining expectations for ITER based on our present knowledge.

Low Energy X-Ray and Electron Physics and Technology for High-Temperature Plasma Diagnostics

DTIC Science & Technology

1987-10-01

This program in low-energy x-ray physics and technology has expanded into a major program with the principal objective of supporting research and application programs at the new large x-ray source facilities, particularly the high temperature plasma and synchrotron radiation sources. This program addresses the development of absolute x-ray diagnostics for the fusion energy and x-ray laser research and development. The new laboratory includes five specially designed

Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)

DOE PAGES

Krychowiak, M.

2016-10-27

Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered amore » MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. Finally, an overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.« less

Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)

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

Krychowiak, M.

Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered amore » MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. Finally, an overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.« less

RF attenuation as a dusty plasma diagnostic

NASA Astrophysics Data System (ADS)

Doyle, Brandon; Konopka, Uwe; Thomas, Edward

2017-10-01

When a dusty plasma is formed by adding dust to a plasma environment, the electron density of the background plasma is depleted as the dust particles acquire their negative charge. The magnitude of the electron depletion depends on the dust particle charge, and thus its properties, as well as the dust number density. A direct measurement of the electron density in a dusty plasma therefore contains information about the charging state of the dust particles. This measurement is difficult to obtain without influencing the system. For example, Langmuir probes influence the system by creating voids, or they become unreliable due to their potential contamination with dust. A less invasive diagnostic tool might be realized using plasma chamber electrodes for a plasma impedance measurement as it depends on the excitation frequency: the spatially averaged electron density is derived from the electron plasma frequency, which is related to the radio frequency attenuation characteristic. We present preliminary experiments using two impedance probe designs: probes immersed in a plasma and electrodes located at the edge of the plasma. We evaluate the potential application of this method for ground-based laboratory experiments and future microgravity experiment facilities aboard the ISS. This work was supported by JPL/NASA (JPL-RSA 1571699) the US Dept. of Energy (DE-SC0016330) and NSF (PHY-1613087).

Development of an energy analyzer as diagnostic of beam-generated plasma in negative ion beam systems

NASA Astrophysics Data System (ADS)

Sartori, E.; Carozzi, G.; Veltri, P.; Spolaore, M.; Cavazzana, R.; Antoni, V.; Serianni, G.

2017-08-01

The measurement of the plasma potential and the energy spectrum of secondary particles in the drift region of a negative ion beam offers an insight into beam-induced plasma formation and beam transport in low pressure gasses. Plasma formation in negative-ion beam systems, and the characteristics of such a plasma are of interest especially for space charge compensation, plasma formation in neutralizers, and the development of improved schemes of beam-induced plasma neutralisers for future fusion devices. All these aspects have direct implications in the ITER Heating Neutral Beam and the operation of the prototypes, SPIDER and MITICA, and also have important role in the conceptual studies for NBI systems of DEMO, while at present experimental data are lacking. In this paper we present the design and development of an ion energy analyzer to measure the beam plasma formation and space charge compensation in negative ion beams. The diagnostic is a retarding field energy analyzer (RFEA), and will measure the transverse energy spectra of plasma molecular ions. The calculations that supported the design are reported, and a method to interpret the measurements in negative ion beam systems is also proposed. Finally, the experimental results of the first test in a magnetron plasma are presented.

Plasma flow measurements in the Prototype-Material Plasma Exposure eXperiment (Proto-MPEX) and comparison with B2.5-Eirene modeling

NASA Astrophysics Data System (ADS)

Kafle, N.; Owen, L. W.; Caneses, J. F.; Biewer, T. M.; Caughman, J. B. O.; Donovan, D. C.; Goulding, R. H.; Rapp, J.

2018-05-01

The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) at Oak Ridge National Laboratory is a linear plasma device that combines a helicon plasma source with additional microwave and radio frequency heating to deliver high plasma heat and particle fluxes to a target. Double Langmuir probes and Thomson scattering are being used to measure local electron temperature and density at various radial and axial locations. A recently constructed Mach-double probe provides the added capability of simultaneously measuring electron temperatures ( T e), electron densities ( n e), and Mach numbers (M). With this diagnostic, it is possible to infer the plasma flow, particle flux, and heat flux at different locations along the plasma column in Proto-MPEX. Preliminary results show Mach numbers of 0.5 (towards the dump plate) and 1.0 (towards the target plate) downstream from the helicon source, and a stagnation point (no flow) near the source for the case where the peak magnetic field was 1.3 T. Measurements of particle flow and ne and Te profiles are discussed. The extensive coverage provided by these diagnostics permits data-constrained B2.5-Eirene modeling of the entire plasma column, and comparison with results of modeling in the high-density helicon plasmas will be presented.

RPR test

MedlinePlus

Rapid plasma reagin test; Syphilis screening test ... Chernecky CC, Berger BJ. Rapid plasma regain (RPR) test – blood. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures . 6th ed. St Louis, MO: Elsevier ...

Temperature and Electron Density Determination on Laser-Induced Breakdown Spectroscopy (LIBS) Plasmas: A Physical Chemistry Experiment

ERIC Educational Resources Information Center

Najarian, Maya L.; Chinni, Rosemarie C.

2013-01-01

This laboratory is designed for physical chemistry students to gain experience using laser-induced breakdown spectroscopy (LIBS) in understanding plasma diagnostics. LIBS uses a high-powered laser that is focused on the sample causing a plasma to form. The emission of this plasma is then spectrally resolved and detected. Temperature and electron…

Formation of Imploding Plasma Liners for HEDP and MIF Applications - Diagnostics

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

Gilmore, Mark; Hsu, Scott; Witherspoon, F. Douglas

The goal of the plasma liner experiment (PLX) was to explore and demonstrate the feasibility of forming imploding spherical plasma liners that can reach High Energy Density (HED)-relevant (~ 0.1 Mbar) pressures upon stagnation. The plasma liners were to be formed by a spherical array of 30 – 36 railgun-driven hypervelocity plasma jets (Mach 10 – 50). Due to funding and project scope reductions in year two of the project, this initial goal was revised to focus on studies of individual jet propagation, and on two jet merging physics. PLX was a collaboration between a number of partners including Losmore » Alamos National Laboratory, HyperV Technologies, University of New Mexico (UNM), University of Alabama, Huntsville, and University of Nevada, Reno. UNM’s part in the collaboration was primary responsibility for plasma diagnostics. Though full plasma liner experiments could not be performed, the results of single and two jet experiments nevertheless laid important groundwork for future plasma liner investigations. Though challenges were encountered, the results obtained with one and two jets were overwhelmingly positive from a liner formation point of view, and were largely in agreement with predictions of hydrodynamic models.« less

An Overview of NSTX Research Facility and Recent Experimental Results

NASA Astrophysics Data System (ADS)

Ono, Masayuki

2006-10-01

The 2006 NSTX experimental campaign yielded significant new experimental results in many areas. Improved plasma control achieved the highest elongation of 2.9 and plasma shape factor q95Ip/aBT = 42 MA/m.T. Active feedback correction of error fields sustained the plasma rotation and increased the pulse length of high beta discharges. Active feedback stabilization of the resistive wall mode in high-beta, low-rotation plasmas was demonstrated for ˜100 resistive wall times. Operation at higher toroidal field showed favorable plasma confinement and HHFW heating efficiency trends with the field. A broader current profile, measured by the 12-channel MSE diagnostic in high beta discharges revealed an outward anomalous diffusivity of energetic ions due to the n=1 MHD modes. A tangential microwave scattering diagnostic measured localized electron gyro-scale fluctuations in L-mode, H-mode and reversed-shear plasmas. Evaporation of lithium onto plasma facing surfaces yielded lower density, higher temperature and improved confinement. A strong dependence of the divertor heat load and ELM behavior on the plasma triangularity was observed. Coaxial helicity injection produced a start-up current of 160 kA on closed flux surfaces.

Characterization of a linear device developed for research on advanced plasma imaging and dynamicsa)

NASA Astrophysics Data System (ADS)

Chung, J.; Lee, K. D.; Seo, D. C.; Nam, Y. U.; Choi, M. C.

2010-10-01

Within the scope of long term research on imaging diagnostics for steady-state plasmas and understanding of edge plasma physics through diagnostics with conventional spectroscopic methods, we have constructed a linear electron cyclotron resonance (ECR) plasma device named Research on Advanced Plasma Imaging and Dynamics (RAPID). It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. Here, a 6 kW 2.45 GHz magnetron is used to produce steady-state hydrogen, helium, and argon plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). In order to achieve the highest possible plasma performance within the limited input parameters, wall conditioning experiments were carried out. Chamber bake-out was achieved with heating coils that were wound covering the vessel, and long-pulse electron cyclotron heating discharge cleaning was also followed after 4 days of bake-out. A uniform bake-out temperature (150 °C) was achieved by wrapping the vessel in high temperature thermal insulation textile and by controlling the heating coil current using a digital control system. The partial pressure changes were observed using a residual gas analyzer, and a total system pressure of 5×10-8 Torr was finally reached. Diagnostic systems including a millimeter-wave interferometer, a high resolution survey spectrometer, a Langmuir probe, and an ultrasoft x-ray detector were used to provide the evidence that the plasma performance was improved as we desired. In this work, we present characterization of the RAPID device for various system conditions and configurations.

Combination of plasma HA and circulating M2-like monocytes may serve as a diagnostic marker for breast cancer.

PubMed

Zhang, Boke; Cao, Manlin; He, Yiqing; Liu, Yiwen; Zhang, Guoliang; Yang, Cuixia; Du, Yan; Xu, Jing; Hu, Jiajie; Gao, Feng

2017-01-01

Background: Breast cancer (BC)-derived hyaluronan (HA) can induce the formation of M2-like tumor-associated macrophages (TAMs) in tumor context. However, little is known about the correlation between circulating M2-like monocytes and plasma HA in BC patients. This study focused on evaluating the relationship between circulating M2-like monocytes and plasma HA, and further appraised the diagnostic value of them in BC. Methods: The expression of M2-like TAMs and HA was determined in pathological tissues by immunohistochemistry. Flow cytometry was used to detect the levels of circulating CD14 + CD204 + M2-like monocytes in 81 BC patients, 45 patients with breast benign diseases, and 46 healthy subjects. The levels of HA, CEA, and CA15-3 were measured in plasma samples using chemiluminescence method. Results: M2-like TAMs and HA expressions were elevated in BC tissues compared with benign tissues. In correspondence, the frequency of circulating CD14 + CD204 + M2-like monocytes and the plasma HA levels were significantly higher in patients with BC than those in control groups. Importantly, there was a positive correlation between circulating M2-like monocytes and the plasma HA (Spearman r = 0.404, p < 0.001). Area under receiver operating characteristic curve (ROC) for the combination of circulating M2-like monocytes and HA was 0.899 (95% CI: 0.853-0.946), which was higher than the panel of CEA and CA15-3. Conclusions: The frequency of circulating CD14 + CD204 + M2-like monocytes was positively correlated to plasma HA levels. The combination of circulating CD14 + CD204 + M2-like monocytes and plasma HA could provide considerable diagnostic value in BC.

Laser-induced breakdown spectroscopy (LIBS), part I: review of basic diagnostics and plasma-particle interactions: still-challenging issues within the analytical plasma community.

PubMed

Hahn, David W; Omenetto, Nicoló

2010-12-01

Laser-induced breakdown spectroscopy (LIBS) has become a very popular analytical method in the last decade in view of some of its unique features such as applicability to any type of sample, practically no sample preparation, remote sensing capability, and speed of analysis. The technique has a remarkably wide applicability in many fields, and the number of applications is still growing. From an analytical point of view, the quantitative aspects of LIBS may be considered its Achilles' heel, first due to the complex nature of the laser-sample interaction processes, which depend upon both the laser characteristics and the sample material properties, and second due to the plasma-particle interaction processes, which are space and time dependent. Together, these may cause undesirable matrix effects. Ways of alleviating these problems rely upon the description of the plasma excitation-ionization processes through the use of classical equilibrium relations and therefore on the assumption that the laser-induced plasma is in local thermodynamic equilibrium (LTE). Even in this case, the transient nature of the plasma and its spatial inhomogeneity need to be considered and overcome in order to justify the theoretical assumptions made. This first article focuses on the basic diagnostics aspects and presents a review of the past and recent LIBS literature pertinent to this topic. Previous research on non-laser-based plasma literature, and the resulting knowledge, is also emphasized. The aim is, on one hand, to make the readers aware of such knowledge and on the other hand to trigger the interest of the LIBS community, as well as the larger analytical plasma community, in attempting some diagnostic approaches that have not yet been fully exploited in LIBS.

Tailoring non-equilibrium atmospheric pressure plasmas for healthcare technologies

NASA Astrophysics Data System (ADS)

Gans, Timo

2012-10-01

Non-equilibrium plasmas operated at ambient atmospheric pressure are very efficient sources for energy transport through reactive neutral particles (radicals and metastables), charged particles (ions and electrons), UV radiation, and electro-magnetic fields. This includes the unique opportunity to deliver short-lived highly reactive species such as atomic oxygen and atomic nitrogen. Reactive oxygen and nitrogen species can initiate a wide range of reactions in biochemical systems, both therapeutic and toxic. The toxicological implications are not clear, e.g. potential risks through DNA damage. It is anticipated that interactions with biological systems will be governed through synergies between two or more species. Suitable optimized plasma sources are improbable through empirical investigations. Quantifying the power dissipation and energy transport mechanisms through the different interfaces from the plasma regime to ambient air, towards the liquid interface and associated impact on the biological system through a new regime of liquid chemistry initiated by the synergy of delivering multiple energy carrying species, is crucial. The major challenge to overcome the obstacles of quantifying energy transport and controlling power dissipation has been the severe lack of suitable plasma sources and diagnostic techniques. Diagnostics and simulations of this plasma regime are very challenging; the highly pronounced collision dominated plasma dynamics at very small dimensions requires extraordinary high resolution - simultaneously in space (microns) and time (picoseconds). Numerical simulations are equally challenging due to the inherent multi-scale character with very rapid electron collisions on the one extreme and the transport of chemically stable species characterizing completely different domains. This presentation will discuss our recent progress actively combining both advance optical diagnostics and multi-scale computer simulations.

First Plasma Results from the Levitated Dipole Experiment

NASA Astrophysics Data System (ADS)

Garnier, Darren T.

2005-04-01

On August 13, 2004, the first plasma physics experiments were conducted using the Levitated Dipole Experiment(LDX)http://www.psfc.mit.edu/ldx/. LDX was built at MIT's Plasma Science and Fusion Center as a joint research project of Columbia University and MIT. LDX is a first-of-its-kind experiment incorporating three superconducting magnets and exploring the physics of high-temperature plasma confined by dipole magnetic fields, similar to planetary magnetospheres. It will test recent theories that suggest that stable, high-β plasma can be confined without good curvature or magnetic shear, instead using plasma compressibility to provide stability. (Plasma β is the ratio of plasma pressure to magnetic pressure.) In initial experiments, 750 kA of current was induced in the dipole coil which was physically supported in the center of the 5 m diameter vacuum chamber. Deuterium plasma discharges, lasting from 4 to 10 seconds, were formed with multi-frequency ECRH microwave heating of up to 6.2 kW. Each plasma contained a large fraction of energetic and relativistic electrons that created a significant pressure that caused outward expansion of the magnetic field. Reconstruction of the magnetic equilibrium from external magnetic diagnostics indicate local peak plasma β 7 %. Along with an overview of the LDX device, results from numerous diagnostics operating during this initial supported campaign measuring the basic plasma parameters will be presented. In addition, observations of instabilities leading to rapid plasma loss and the effects of changing plasma compressibility will be explored.

ENO1 Overexpression in Pancreatic Cancer Patients and Its Clinical and Diagnostic Significance

PubMed Central

Yin, Hang; Wang, Lei

2018-01-01

We investigated in this study the expression of ENO1 in tissues and plasma of PDAC patients to evaluate its clinicopathological and diagnostic significance. ENO1 protein expression was detected in tissue microarray of human PDAC and adjacent noncancer tissues. Electrochemiluminescence immunoassay and amplified luminescent proximity homogeneous assay (AlphaLISA) were performed to measure CA19-9 and ENO1 concentration in plasma from PDAC patients and healthy controls. We demonstrated that ENO1 overexpression is positively correlated with clinical stage, lymph node metastasis, and poor prognosis of PDAC; ENO1 may function as a hopeful candidate diagnostic marker in combination with CA19-9 in PDAC diagnosis. PMID:29483925

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

Stutman, D.; Tritz, K.; Finkenthal, M.

New diagnostic and sensor designs are needed for future burning plasma (BP) fusion experiments, having good space and time resolution and capable of prolonged operation in the harsh BP environment. We evaluate the potential of multi-energy x-ray imaging with filtered detector arrays for BP diagnostic and control. Experimental studies show that this simple and robust technique enables measuring with good accuracy, speed, and spatial resolution the T{sub e} profile, impurity content, and MHD activity in a tokamak. Applied to the BP this diagnostic could also serve for non-magnetic sensing of the plasma position, centroid, ELM, and RWM instability. BP compatiblemore » x-ray sensors are proposed using 'optical array' or 'bi-cell' detectors.« less

Comparison of Plasma and Urine Biomarker Performance in Acute Kidney Injury

PubMed Central

Schley, Gunnar; Köberle, Carmen; Manuilova, Ekaterina; Rutz, Sandra; Forster, Christian; Weyand, Michael; Formentini, Ivan; Kientsch-Engel, Rosemarie; Eckardt, Kai-Uwe; Willam, Carsten

2015-01-01

Background New renal biomarkers measured in urine promise to increase specificity for risk stratification and early diagnosis of acute kidney injury (AKI) but concomitantly may be altered by urine concentration effects and chronic renal insufficiency. This study therefore directly compared the performance of AKI biomarkers in urine and plasma. Methods This single-center, prospective cohort study included 110 unselected adults undergoing cardiac surgery with cardiopulmonary bypass between 2009 and 2010. Plasma and/or urine concentrations of creatinine, cystatin C, neutrophil gelatinase-associated lipocalin (NGAL), liver fatty acid-binding protein (L-FABP), kidney injury molecule 1 (KIM1), and albumin as well as 15 additional biomarkers in plasma and urine were measured during the perioperative period. The primary outcome was AKI defined by AKIN serum creatinine criteria within 72 hours after surgery. Results Biomarkers in plasma showed markedly better discriminative performance for preoperative risk stratification and early postoperative (within 24h after surgery) detection of AKI than urine biomarkers. Discriminative power of urine biomarkers improved when concentrations were normalized to urinary creatinine, but urine biomarkers had still lower AUC values than plasma biomarkers. Best diagnostic performance 4h after surgery had plasma NGAL (AUC 0.83), cystatin C (0.76), MIG (0.74), and L-FAPB (0.73). Combinations of multiple biomarkers did not improve their diagnostic power. Preoperative clinical scoring systems (EuroSCORE and Cleveland Clinic Foundation Score) predicted the risk for AKI (AUC 0.76 and 0.71) and were not inferior to biomarkers. Preexisting chronic kidney disease limited the diagnostic performance of both plasma and urine biomarkers. Conclusions In our cohort plasma biomarkers had higher discriminative power for risk stratification and early diagnosis of AKI than urine biomarkers. For preoperative risk stratification of AKI clinical models showed similar discriminative performance to biomarkers. The discriminative performance of both plasma and urine biomarkers was reduced by preexisting chronic kidney disease. PMID:26669323

Diagnostics of jaundice from the change of the transmission coefficient of the human body

NASA Astrophysics Data System (ADS)

Guminetskiy, S. G.; Kirsh, N. L.; Lomanets, V. S.; Lazurka, I. I.; Yakobets, I. I.

2004-06-01

The paper deals with the absorption spectra of bilirubin solutions, patient blood plasma with jaundice manifestations with a different degree of disease and whole blood. Using as an analysis base the dependencies of blood plasma absorption spectra on bilirubin concentration in this blood there has been proposed the method of disease diagnostics with jaundice manifestations, and there has been realized the corresponding portable laboratory device, the functioning of which is based on registering the radiation propagated through the ear lobule.

Nuclear diagnostic for fast alpha particles

DOEpatents

Grisham, L.R.; Post, D.E. Jr.; Dawson, J.M.

1983-11-23

This invention relates generally to high energy confined plasmas and more particularly is directed to measuring the velocity distribution of confined energetic alpha particles resulting from deuterium-tritium fusion reactions in a confined energetic plasma.

Screening spectroscopy of prostate cancer

NASA Astrophysics Data System (ADS)

Yermolenko, S. B.; Voloshynskyy, D. I.; Fedoruk, O. S.

2015-11-01

The aim of the study was to establish objective parameters of the field of laser and incoherent radiation of different spectral ranges (UV, visible, IR) as a non-invasive optical method of interaction with different samples of biological tissues and fluids of patients to determine the state of prostate cancer and choosing the best personal treatment. The objects of study were selected venous blood plasma of patient with prostate cancer, histological sections of rat prostate gland in the postoperative period. As diagnostic methods have been used ultraviolet spectrometry samples of blood plasma in the liquid state, infrared spectroscopy middle range (2,5-25 microns) dry residue of plasma by spectral diagnostic technique of thin histological sections of biological tissues.

Summary of ECE presentations at EC-18

DOE PAGES

Taylor, G.

2015-03-12

There were nine ECE and one EBE presentation at EC-18. Four of the presentations were on various aspects of ECE on ITER. The ITER ECE diagnostic has entered an important detailed preliminary design phase and faces several design challenges in the next 2-3 years. Most of the other ECE presentations at the workshop were focused on applications of ECE diagnostics to plasma measurements, rather than improvements in technology, although it was apparent that heterodyne receiver technology continues to improve. CECE, ECE imaging and EBE imaging are increasingly providing valuable insights into plasma behavior that is important to understand if futuremore » burning plasma devices, such as ITER, FNSF and DEMO, are to be successful.« less

The TFTR E Parallel B Spectrometer for Mass and Energy Resolved Multi-Ion Charge Exchange Diagnostics

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

A.L. Roquemore; S.S. Medley

1998-01-01

The Charge Exchange Neutral Analyzer diagnostic for the Tokamak Fusion Test Reactor was designed to measure the energy distributions of both the thermal ions and the supra thermal populations arising from neutral-beam injection and ion cyclotron radio-frequency heating. These measurements yield the plasma ion temperature, as well as several other plasma parameters necessary to provide an understanding of the plasma condition and the performance of the auxiliary heating methods. For this application, a novel charge-exchange spectrometer using a dee-shaped region of parallel electric and magnetic fields was developed at the Princeton Plasma Physics Laboratory. The design and performance of thismore » spectrometer is described in detail, including the effects of exposure of the microchannel plate detector to magnetic fields, neutrons, and tritium.« less

A review of the findings of the plasma diagnostic package and associated laboratory experiments: Implications of large body/plasma interactions for future space technology

NASA Technical Reports Server (NTRS)

Murphy, Gerald B.; Lonngren, Karl E.

1986-01-01

The discoveries and experiments of the Plasma Diagnostic Package (PDP) on the OSS 1 and Spacelab 2 missions are reviewed, these results are compared with those of other space and laboratory experiments, and the implications for the understanding of large body interactions in a low Earth orbit (LEO) plasma environment are discussed. First a brief review of the PDP investigation, its instrumentation and experiments is presented. Next a summary of PDP results along with a comparison of those results with similar space or laboratory experiments is given. Last of all the implications of these results in terms of understanding fundamental physical processes that take place with large bodies in LEO is discussed and experiments to deal with these vital questions are suggested.

Development and characterization of semiconductor ion detectors for plasma diagnostics in the range over 0.3 keV

NASA Astrophysics Data System (ADS)

Cho, T.; Sakamoto, Y.; Hirata, M.; Kohagura, J.; Makino, K.; Kanke, S.; Takahashi, K.; Okamura, T.; Nakashima, Y.; Yatsu, K.; Tamano, T.; Miyoshi, S.

1997-01-01

For the purpose of plasma-ion-energy analyses in a wide-energy range from a few hundred eV to hundreds of keV, upgraded semiconductor detectors are newly fabricated and characterized using a test-ion-beam line from 0.3 to 12 keV. In particular, the detectable lowest-ion energy is drastically improved at least down to 0.3 keV; this energy is one to two orders-of-magnitude better than those for commercially available Si-surface-barrier diodes employed for previous plasma-ion diagnostics. A signal-to-noise ratio of two to three orders-of-magnitude better than that for usual metal-collector detectors is demonstrated for the compact-sized semiconductor along with the availability of the use under conditions of a good vacuum and a strong-magnetic field. Such characteristics are achieved due to the improving methods of the optimization of the thicknesses of a Si dead layer and a SiO2 layer, as well as the nitrogen-doping technique near the depletion layer along with minimizing impurity concentrations in Si. Such an upgraded capability of an extremely low-energy-ion detection with the low-noise characteristics enlarges research regimes of plasma-ion behavior using semiconductor detectors not only in the divertor regions of tokamaks but in wider spectra of open-field plasma devices including tandem mirrors. An application of the semiconductor ion detector for plasma-ion diagnostics is demonstrated in a specially designed ion-spectrometer structure.

[The possibility of using PlasmaDeepDive™ MRM panel in clinical diagnostics].

PubMed

Miroshnichenko, Iu V; Petushkova, N A; Moskaleva, N E; Teryaeva, N B; Zgoda, V G; Ilgisonis, E V; Belyaev, A Yu

2015-01-01

Concentrations of 46 proteins have been determined in human blood plasma using PlasmaDeepDive™ MRM Panel ("Biognosys AG", Switzerland). 18 of them were included into the group of proteins with higher concentrations, also identified by the shotgun proteomic analysis. Based on literature data it is concluded that the PlasmaDeepDive™ MRM Panel is applicable for studies of human plasma samples for potential biomarkers of various nervous system disorders.

Direct-Coupled Plasma-Assisted Combustion Using a Microwave Waveguide Torch

DTIC Science & Technology

2011-12-01

enhance combustion by coupling an atmospheric plasma dis- charge to a premixed methane/air flame. The absorbed microwave power ranges from 60 to 150 W...The plasma system allows for complete access of the plasma- enhanced flame for laser and optical diagnostics 0093-3813/$26.00 © 2011 IEEE Report...microwave waveguide is used to initiate and enhance combustion by coupling an atmospheric plasma discharge to a premixed methane/air flame. The

Biomarker Development for Intraductal Papillary Mucinous Neoplasms Using Multiple Reaction Monitoring Mass Spectrometry.

PubMed

Kim, Yikwon; Kang, MeeJoo; Han, Dohyun; Kim, Hyunsoo; Lee, KyoungBun; Kim, Sun-Whe; Kim, Yongkang; Park, Taesung; Jang, Jin-Young; Kim, Youngsoo

2016-01-04

Intraductal papillary mucinous neoplasm (IPMN) is a common precursor of pancreatic cancer (PC). Much clinical attention has been directed toward IPMNs due to the increase in the prevalence of PC. The diagnosis of IPMN depends primarily on a radiological examination, but the diagnostic accuracy of this tool is not satisfactory, necessitating the development of accurate diagnostic biomarkers for IPMN to prevent PC. Recently, high-throughput targeted proteomic quantification methods have accelerated the discovery of biomarkers, rendering them powerful platforms for the evolution of IPMN diagnostic biomarkers. In this study, a robust multiple reaction monitoring (MRM) pipeline was applied to discovery and verify IPMN biomarker candidates in a large cohort of plasma samples. Through highly reproducible MRM assays and a stringent statistical analysis, 11 proteins were selected as IPMN marker candidates with high confidence in 184 plasma samples, comprising a training (n = 84) and test set (n = 100). To improve the discriminatory power, we constructed a six-protein panel by combining marker candidates. The multimarker panel had high discriminatory power in distinguishing between IPMN and controls, including other benign diseases. Consequently, the diagnostic accuracy of IPMN can be improved dramatically with this novel plasma-based panel in combination with a radiological examination.

Ionization-potential depression and other dense plasma statistical property studies - Application to spectroscopic diagnostics.

NASA Astrophysics Data System (ADS)

Calisti, Annette; Ferri, Sandrine; Mossé, Caroline; Talin, Bernard

2017-02-01

The radiative properties of an emitter surrounded by a plasma, are modified through various mechanisms. For instance the line shapes emitted by bound-bound transitions are broadened and carry useful information for plasma diagnostics. Depending on plasma conditions the electrons occupying the upper quantum levels of radiators no longer exist as they belong to the plasma free electron population. All the charges present in the radiator environment contribute to the lowering of the energy required to free an electron in the fundamental state. This mechanism is known as ionization potential depression (IPD). The knowledge of IPD is useful as it affects both the radiative properties of the various ionic states and their populations. Its evaluation deals with highly complex n-body coupled systems, involving particles with different dynamics and attractive ion-electron forces. A classical molecular dynamics (MD) code, the BinGo-TCP code, has been recently developed to simulate neutral multi-component (various charge state ions and electrons) plasma accounting for all the charge correlations. In the present work, results on IPD and other dense plasma statistical properties obtained using the BinGo-TCP code are presented. The study focuses on aluminum plasmas for different densities and several temperatures in order to explore different plasma coupling conditions.

Array-based disease diagnostics using lipid/polydiacetylene vesicles encapsulated in a sol-gel matrix.

PubMed

Kolusheva, S; Yossef, R; Kugel, A; Katz, M; Volinsky, R; Welt, M; Hadad, U; Drory, V; Kliger, M; Rubin, E; Porgador, A; Jelinek, R

2012-07-17

We demonstrate a novel array-based diagnostic platform comprising lipid/polydiacetylene (PDA) vesicles embedded within a transparent silica-gel matrix. The diagnostic scheme is based upon the unique chromatic properties of PDA, which undergoes blue-red transformations induced by interactions with amphiphilic or membrane-active analytes. We show that constructing a gel matrix array hosting PDA vesicles with different lipid compositions and applying to blood plasma obtained from healthy individuals and from patients suffering from disease, respectively, allow distinguishing among the disease conditions through application of a simple machine-learning algorithm, using the colorimetric response of the lipid/PDA/gel matrix as the input. Importantly, the new colorimetric diagnostic approach does not require a priori knowledge on the exact metabolite compositions of the blood plasma, since the concept relies only on identifying statistically significant changes in overall disease-induced chromatic response. The chromatic lipid/PDA/gel array-based "fingerprinting" concept is generic, easy to apply, and could be implemented for varied diagnostic and screening applications.

The polarization evolution of electromagnetic waves as a diagnostic method for a motional plasma

NASA Astrophysics Data System (ADS)

Shahrokhi, Alireza; Mehdian, Hassan; Hajisharifi, Kamal; Hasanbeigi, Ali

2017-12-01

The polarization evolution of electromagnetic (EM) radiation propagating through an electron beam-ion channel system is studied in the presence of self-magnetic field. Solving the fluid-Maxwell equations to obtain the medium dielectric tensor, the Stokes vector-Mueller matrix approach is employed to determine the polarization of the launched EM wave at any point in the propagation direction, applying the space-dependent Mueller matrix on the initial polarization vector of the wave at the plasma-vacuum interface. Results show that the polarization evolution of the wave is periodic in space along the beam axis with the specified polarization wavelength. Using the obtained results, a novel diagnostic method based on the polarization evolution of the EM waves is proposed to evaluate the electron beam density and velocity. Moreover, to use the mentioned plasma system as a polarizer, the fraction of the output radiation power transmitted through a motional plasma crossed with the input polarization is calculated. The results of the present investigation will greatly contribute to design a new EM amplifier with fixed polarization or EM polarizer, as well as a new diagnostic approach for the electron beam system where the polarimetric method is employed.

MD-miniRNA could be a more accurate biomarker for prostate cancer screening compared with serum prostate-specific antigen level.

PubMed

Xue, Dong; Zhou, Cui-Xing; Shi, Yun-Bo; Lu, Hao; He, Xiao-Zhou

2015-05-01

Prostate cancer and prostatic hyperplasia detection remains a great challenge, lacking of effective non-invasive and specific diagnostic biomarkers. In the current study, we aimed to identify the relative expression of plasma MD-miniRNA and its diagnostic performance in differentiating prostate cancer and prostatic hyperplasia patients from healthy controls, compared with serum prostate-specific antigen (PSA) level. All of the clinical participants (63 prostate cancer patients, 32 prostatic hyperplasia patients, and 50 healthy controls) were obtained from the Third Affiliated Hospital of Suzhou University in China between January 2013 and April 2014. Clinical characteristics were well matched. Plasma samples were extracted to test the relative expression of MD-miniRNA using the method of qRT-PCR. SPSS 22.0 statistical software package was used to analyze the data and GraphPad Prism 6.0 was used to generate the graphs. Relativity expression of plasma MD-miniRNA was significantly upregulated in prostate cancer, compared with prostatic hyperplasia patients and healthy controls. Serum PSA level revealed similar differences among these groups. MD-miniRNA presented a relatively high diagnostic accuracy with AUC of 0.86 (95 % CI 0.80-0.93) in differentiating prostate cancer patients from healthy controls. Simultaneously, MD-miniRNA was able to discriminate prostate cancer patients from prostatic hyperplasia controls with AUC of 0.79 (95 % CI 0.70-0.88). In addition, MD-miniRNA displayed a better diagnostic performance than PSA level. However, the panel of these two biomarkers revealed the best diagnostic performance, compared with either single biomarker. Results of this study showed that plasma MD-miniRNA could serve as a promising and noninvasive biomarker for diagnosing prostate cancer. Further large-scale studies are needed to confirm its clinical diagnosis accuracy.

Glypican-3 level assessed by the enzyme-linked immunosorbent assay is inferior to alpha-fetoprotein level for hepatocellular carcinoma diagnosis.

PubMed

Jeon, Yejoo; Jang, Eun Sun; Choi, Yun Suk; Kim, Jin-Wook; Jeong, Sook-Hyang

2016-09-01

Glypican-3 (GPC3) protein is highly expressed in hepatocellular carcinoma (HCC) tissue. It has been suggested as a diagnostic biomarker, but its inconsistent performance means that it requires further assessment. We therefore investigated the diagnostic value of the plasma GPC3 level compared to the alpha-fetoprotein (AFP) level as a diagnostic biomarker of HCC. We enrolled 157 consecutive patients with newly diagnosed HCC and 156 patients with liver cirrhosis (LC) as the control group. GPC3 plasma levels were measured using two commercially available enzyme-linked immunosorbent assays (ELISAs, named as Assay 1 and 2), and AFP levels were measured using an enzyme-linked chemiluminescent immunoassay. The diagnostic accuracy was analyzed using the receiver operating characteristics (ROC) curve. Plasma GPC3 levels in HCC patients were very low (0-3.09 ng/mL) in Assay 1, while only 3 of the 157 patients (1.9%) showed detectable GPC3 levels in Assay 2. The median GPC3 level was not significantly elevated in the HCC group (0.80 ng/mL) compared with the LC group (0.60 ng/mL). The area under the ROC curve (AUC) for GPC3 was 0.559 in Assay 1. In contrast, the median AFP level was significantly higher in HCC (27.72 ng/mL) than in LC (4.74 ng/mL), with an AUC of 0.729. The plasma level of GPC3 is a poor diagnostic marker for HCC, being far inferior to AFP. The development of a consistent detection system for the blood level of GPC3 is warranted.

Diagnostic evaluation of the MRP-8/14 for the emergency assessment of chest pain.

PubMed

Vora, Amit N; Bonaca, Marc P; Ruff, Christian T; Jarolim, Petr; Murphy, Sabina; Croce, Kevin; Sabatine, Marc S; Simon, Daniel I; Morrow, David A

2012-08-01

Elevated levels of myeloid-related protein (MRP)-8/14 (S100A8/A9) are associated with first cardiovascular events in healthy individuals and worse prognosis in patients with acute coronary syndrome (ACS). The diagnostic utility of MRP-8/14 in patients presenting to the emergency room with symptoms concerning for ACS is uncertain. MRP-8/14 was measured in serial serum and plasma samples in a single center prospective cohort-study of patients presenting to the emergency room with non-traumatic chest pain concerning for ACS. Final diagnosis was adjudicated by an endpoint committee. Of patients with baseline MRP-8/14 results (n = 411), the median concentration in serum was 1.57 μg/ml (25th, 75th: 0.87, 2.68) and in plasma was 0.41 μg/ml (<0.4, 1.15) with only moderate correlation between serum and plasma (ρ = 0.40). A final diagnosis of MI was made in 106 (26%). Peak serum MRP-8/14 was higher in patients presenting with MI (p < 0.001). However, the overall diagnostic performance of MRP-8/14 was poor: sensitivity 28% (95% CI 20-38), specificity 82% (78-86), positive predictive value 36% (26-47), and negative predictive value 77% (72-81). The area under the ROC curve for diagnosis of MI with MRP-8/14 was 0.55 (95% CI 0.51-0.60) compared with 0.95 for cTnI. The diagnostic performance was not improved in early-presenters, patients with negative initial cTnI, or using later MRP-8/14 samples. Patients presenting with MI had elevated levels of serum MRP-8/14 compared to patients with non-cardiac chest pain. However, overall diagnostic performance of MRP-8/14 was poor and neither plasma nor serum MRP-8/14 offered diagnostic utility comparable to cardiac troponin.

Plasma levels of miRNA-155 as a powerful diagnostic marker for dedifferentiated liposarcoma

PubMed Central

Boro, Aleksandar; Bauer, David; Born, Walter; Fuchs, Bruno

2016-01-01

Atypic lipomatous tumors (ALT) and dedifferentiated liposarcomas (DDLS) are closely related liposarcoma subtypes, often difficult to distinguish but they exhibit an entirely different clinical outcome. Recently discovered regulatory functions of miRNAs in liposarcoma progression prompted us to investigate miRNAs as potential diagnostic biomarkers in liposarcoma with a main focus on circulating miRNAs for fast and reliable differential diagnosis. Tumor and blood samples of 35 patients with lipomatous lesions collected between June 2011 and September 2014 were analyzed by qRT-PCR. They included 10 lipomas, 7 ALT, 5 DDLS and 13 myxoid liposarcomas (MLS). Ten samples of normal fat tissue and blood from 20 healthy volunteers were used as controls. A meta-analysis of public data on miRNA expression in liposarcoma revealed 9 miRNAs with potential diagnostic power. Out of these, miRNA-155 was found significantly elevated in the circulation of DDLS patients as compared to the plasma levels detected in all other liposarcoma subtypes and in healthy subjects. miRNA-155 levels in the plasma samples correlated significantly (r=0.41, p=0.02) with those in corresponding tumor extracts. This correlation was even more pronounced in an analysis of plasma and tumor extracts of malignant liposarcoma subtypes alone (r=0.51, p=0.02). Receiver operating characteristic analysis indicated that plasma miRNA-155 levels have a high diagnostic accuracy for distinguishing DDLS from healthy subjects (AUC=0.91, p=0.005) and from lipomas (AUC=0.86, p=0.02), MLS (AUC=0.92, p=0.006) and most importantly ALT (AUC=0.91, p=0.01) patients. In conclusion, this study identified miRNA-155 as a first blood biomarker for the differential diagnosis of DDLS. PMID:27186423

Optical Diagnostics for Plasma-based Particle Accelerators

NASA Astrophysics Data System (ADS)

Muggli, Patric

2009-05-01

One of the challenges for plasma-based particle accelerators is to measure the spatio-temporal characteristics of the accelerated particle bunch. ``Optical'' diagnostics are particularly interesting and useful because of the large number of techniques that exits to determine the properties of photon pulses. The accelerated bunch can produce photons pulses that carry information about its characteristics for example through synchrotron radiation in a magnet, Cherenkov radiation in a gas, and transition radiation (TR) at the boundary between two media with different dielectric constants. Depending on the wavelength of the emission when compared to the particle bunch length, the radiation can be incoherent or coherent. Incoherent TR in the optical range (or OTR) is useful to measure the transverse spatial characteristics of the beam, such as charge distribution and size. Coherent TR (or CTR) carries information about the bunch length that can in principle be retrieved by standard auto-correlation or interferometric techniques, as well as by spectral measurements. A measurement of the total CTR energy emitted by bunches with constant charge can also be used as a shot-to-shot measurement for the relative bunch length as the CTR energy is proportional to the square of the bunch population and inversely proportional to its length (for a fixed distribution). Spectral interferometry can also yield the spacing between bunches in the case where multiple bunches are trapped in subsequent buckets of the plasma wave. Cherenkov radiation can be used as an energy threshold diagnostic for low energy particles. Cherenkov, synchrotron and transition radiation can be used in a dispersive section of the beam line to measure the bunch energy spectrum. The application of these diagnostics to plasma-based particle accelerators, with emphasis on the beam-driven, plasma wakefield accelerator (PWFA) at the SLAC National Accelerator Laboratory will be discussed.

Optical diagnostics on the Magnetized Shock Experiment (MSX)

NASA Astrophysics Data System (ADS)

Boguski, J. C.; Weber, T. E.; Intrator, T. P.; Smith, R. J.; Dunn, J. P.; Hutchinson, T. M.; Gao, K. W.

2013-10-01

The Magnetized Shock Experiment (MSX) at Los Alamos National Laboratory was built to investigate the physics of high Alfvén Mach number, supercritical, magnetized shocks through the acceleration and subsequent stagnation of a Field Reversed Configuration (FRC) plasmoid against a magnetic mirror and/or plasma target. A suite of optical diagnostics has recently been fielded on MSX to characterize plasma conditions during the formation, acceleration, and stagnation phases of the experiment. CCD-backed streak and framing cameras, and a fiber-based visible light array, provide information regarding FRC shape, velocity, and instability growth. Time-resolved narrow and broadband spectroscopy provides information on pre-shock plasma temperature, impurity levels, shock location, and non-thermal ion distributions within the shock region. Details of the diagnostic design, configuration, and characterization will be presented along with initial results. This work is supported by the Center for Magnetic Self Organization, DoE OFES and NNSA under LANS contract DE-AC52-06NA25369. Approved for public release: LA-UR- 13-25190.

Submillimeter Spectroscopic Diagnostics in Semiconductor Processing Plasmas

NASA Astrophysics Data System (ADS)

Helal, Yaser H.; Neese, Christopher F.; De Lucia, Frank C.; Ewing, Paul R.; Stout, Phillip J.; Walker, Quentin; Armacost, Michael D.

2014-06-01

Submillimeter absorption spectroscopy was used to study semiconductor processing plasmas. Abundances and temperatures of molecules, radicals, and ions can be determined without altering any of the properties of the plasma. The behavior of these measurements provides useful applications in monitoring process steps. A summary of such applications will be presented, including etching and cleaning endpoint detection.

Velocity Space Degrees of Freedom of Plasma Fluctuations

NASA Astrophysics Data System (ADS)

Mattingly, Sean

2017-10-01

Small scale wave modes are becoming more important in plasma physics. Examples include turbulent cascades in the solar wind, the energetics of fusion plasma electrostatic turbulence and transport, and low temperature basic plasma physics experiments. In order to improve our understanding of these modes, I present an advance in experimental plasma diagnostics and use it to show the first measurement of a plasma ion velocity-space cross-correlation matrix. From this matrix I determine the eigenmodes of fluctuations on the ion distribution function as a function of frequency. I also determine the relative strengths of these modes - these are the velocity space degrees of freedom of plasma fluctuations. This measurement can detect the aforementioned smaller scale modes in plasmas through a localized measurement. The locality of this measurement means that it may be applied to plasmas in which a single - point velocity sensitive diagnostic is available and multipoint measurements may be difficult. Examples include in situ measurements of space plasmas, fusion plasmas, trapped plasmas, and laser cooled plasmas. This fact, combined with the new perspective it can give on small scale plasma fluctuations, means it may be used to further research on the above cited subjects. Much work remains on fully understanding this measurement. This measurement opens a velocity space interpretation of small scale plasma wave modes, and understanding this perspective from theory requires the application or invention of new mathematical tools. I discuss open problems to follow up on, which include questions from experimental, theoretical, and instrumentation perspectives. NSF-DOE Program Grant DE-FG02-99ER54543.

Description of the plasma diagnostics package (PDP) for the OSS-1 Shuttle mission and JSC plasma chamber test in conjunction with the fast pulse electron gun (FPEG)

NASA Technical Reports Server (NTRS)

Shawhan, S. D.

1982-01-01

The objectives, equipment, and techniques for the plasma diagnostics package (PDP) carried by the OSS-1 instrument payload of the STS-4 and scheduled for the Spacelab-2 mission are described. The goals of the first flight were to examine the Orbiter-magnetoplasma interactions by measuring the electric and magnetic field strengths, the ionized particle wakes, and the generated waves. The RMS was employed to lift the unit out of the bay in order to allow characterization of the fields, EM interference, and plasma contamination within 15 m of the Orbiter. The PDP will also be used to examine plasma depletion, chemical reaction rates, waves, and energized plasma produced by firing of the Orbiter thrusters. Operation of the PDP was carried out in the NASA Space Environment Simulation Laboratory test chamber, where the PDP was used to assay the fields, fluxes, wave amplitudes, and particle energy spectra. The PDP instrumentation is also capable of detecting thermal ions, thermal electrons suprathermal particles, VHF/UHF EMI levels, and the S-band field strength.

Method for generating a plasma wave to accelerate electrons

DOEpatents

Umstadter, D.; Esarey, E.; Kim, J.K.

1997-06-10

The invention provides a method and apparatus for generating large amplitude nonlinear plasma waves, driven by an optimized train of independently adjustable, intense laser pulses. In the method, optimal pulse widths, interpulse spacing, and intensity profiles of each pulse are determined for each pulse in a series of pulses. A resonant region of the plasma wave phase space is found where the plasma wave is driven most efficiently by the laser pulses. The accelerator system of the invention comprises several parts: the laser system, with its pulse-shaping subsystem; the electron gun system, also called beam source, which preferably comprises photo cathode electron source and RF-LINAC accelerator; electron photo-cathode triggering system; the electron diagnostics; and the feedback system between the electron diagnostics and the laser system. The system also includes plasma source including vacuum chamber, magnetic lens, and magnetic field means. The laser system produces a train of pulses that has been optimized to maximize the axial electric field amplitude of the plasma wave, and thus the electron acceleration, using the method of the invention. 21 figs.

Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

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

Brombin, M., E-mail: matteo.brombin@igi.cnr.it; Spolaore, M.; Serianni, G.

2014-11-15

A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors’ holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation.more » No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.« less

Neutral helium beam probe

NASA Astrophysics Data System (ADS)

Karim, Rezwanul

1999-10-01

This article discusses the development of a code where diagnostic neutral helium beam can be used as a probe. The code solves numerically the evolution of the population densities of helium atoms at their several different energy levels as the beam propagates through the plasma. The collisional radiative model has been utilized in this numerical calculation. The spatial dependence of the metastable states of neutral helium atom, as obtained in this numerical analysis, offers a possible diagnostic tool for tokamak plasma. The spatial evolution for several hypothetical plasma conditions was tested. Simulation routines were also run with the plasma parameters (density and temperature profiles) similar to a shot in the Princeton beta experiment modified (PBX-M) tokamak and a shot in Tokamak Fusion Test Reactor tokamak. A comparison between the simulation result and the experimentally obtained data (for each of these two shots) is presented. A good correlation in such comparisons for a number of such shots can establish the accurateness and usefulness of this probe. The result can possibly be extended for other plasma machines and for various plasma conditions in those machines.

Beam-Plasma Interaction Experiments on the Princeton Advanced Test Stand

NASA Astrophysics Data System (ADS)

Stepanov, A.; Gilson, E. P.; Grisham, L.; Kaganovich, I. D.; Davidson, R. C.

2011-10-01

The Princeton Advanced Test Stand (PATS) is a compact experimental facility for studying the fundamental physics of intense beam-plasma interactions relevant to the Neutralized Drift Compression Experiment - II (NDCX-II). The PATS facility consists of a 100 keV ion beam source mounted on a six-foot-long vacuum chamber with numerous ports for diagnostic access. A 100 keV Ar+ beam is launched into a volumetric plasma, which is produced by a ferroelectric plasma source (FEPS). Beam diagnostics upstream and downstream of the FEPS allow for detailed studies of the effects that the plasma has on the beam. This setup is designed for studying the dependence of charge and current neutralization and beam emittance growth on the beam and plasma parameters. This work reports initial measurements of beam quality produced by the extraction electrodes that were recently installed on the PATS device. The transverse beam phase space is measured with double-slit emittance scanners, and the experimental results are compared to WARP simulations of the extraction system. This research is supported by the U.S. Department of Energy.

Generation of disc-like plasma from laser-matter interaction in the presence of a strong external magnetic field

DOE PAGES

Ivanov, V. V.; Maximov, A. V.; Betti, R.; ...

2017-05-16

Dynamics of laser produced plasma in a strong magnetic field was studied here using a 1 MA pulsed power generator coupled to an intense, high-energy laser. A 2–2.5 MG magnetic field was generated on the surface of a rod load 0.8–1.2 mm in diameter. A sub-nanosecond laser pulse with intensity of 3 × 10 15 W cm -2 was focused on the rod load surface. Side-on laser diagnostics showed the generation of two collimated jets 1–3 mm long on the front and rear sides of the load. End-on laser diagnostics reveal that the laser produced plasma in the MG magneticmore » field takes the form of a thin disc as the plasma propagates along the magnetic field lines. The disc-like plasma expands radially across the magnetic field with a velocity of 250 km s -1. An electron temperature of 400 eV was measured in the laser-produced plasma on the rod load.« less

Method for generating a plasma wave to accelerate electrons

DOEpatents

Umstadter, Donald; Esarey, Eric; Kim, Joon K.

1997-01-01

The invention provides a method and apparatus for generating large amplitude nonlinear plasma waves, driven by an optimized train of independently adjustable, intense laser pulses. In the method, optimal pulse widths, interpulse spacing, and intensity profiles of each pulse are determined for each pulse in a series of pulses. A resonant region of the plasma wave phase space is found where the plasma wave is driven most efficiently by the laser pulses. The accelerator system of the invention comprises several parts: the laser system, with its pulse-shaping subsystem; the electron gun system, also called beam source, which preferably comprises photo cathode electron source and RF-LINAC accelerator; electron photo-cathode triggering system; the electron diagnostics; and the feedback system between the electron diagnostics and the laser system. The system also includes plasma source including vacuum chamber, magnetic lens, and magnetic field means. The laser system produces a train of pulses that has been optimized to maximize the axial electric field amplitude of the plasma wave, and thus the electron acceleration, using the method of the invention.

The effects of magnetic nozzle configurations on plasma thrusters

NASA Technical Reports Server (NTRS)

York, Thomas M.

1989-01-01

Plasma thrusters have been operated at power levels from 10kW to 0.1MW. When these devices have had magnetic fields applied to them which form a nozzle configuration for the expanding plasma, they have shown marked increases in exhaust velocity which is in direct proportion to the magnitude of the applied field. Further, recent results have shown that electrode erosion may be influenced by applied magnetic fields. This research is directed to the experimental and computational study of the effects of applied magnetic field nozzles in the acceleration of plasma flows. Plasma source devices which eliminate the plasma interaction in normal thrusters are studied as most basic. Normal thruster configurations will be studied without applied fields and with applied magnetic nozzle fields. Unique computational studies will utilize existing codes which accurately include transport processes. Unique diagnostic studies will support the experimental studies to generate new data. Both computation and diagnostics will be combined to indicate the physical mechanisms and transport properties that are operative in order to allow scaling and accurate prediction of thruster performance.

Generation of disc-like plasma from laser-matter interaction in the presence of a strong external magnetic field

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

Ivanov, V. V.; Maximov, A. V.; Betti, R.

Dynamics of laser produced plasma in a strong magnetic field was studied here using a 1 MA pulsed power generator coupled to an intense, high-energy laser. A 2–2.5 MG magnetic field was generated on the surface of a rod load 0.8–1.2 mm in diameter. A sub-nanosecond laser pulse with intensity of 3 × 10 15 W cm -2 was focused on the rod load surface. Side-on laser diagnostics showed the generation of two collimated jets 1–3 mm long on the front and rear sides of the load. End-on laser diagnostics reveal that the laser produced plasma in the MG magneticmore » field takes the form of a thin disc as the plasma propagates along the magnetic field lines. The disc-like plasma expands radially across the magnetic field with a velocity of 250 km s -1. An electron temperature of 400 eV was measured in the laser-produced plasma on the rod load.« less

A review of direct experimental measurements of detachment

DOE PAGES

Boedo, J.; McLean, A. G.; Rudakov, D. L.; ...

2018-02-22

Detached divertor plasmas feature strong radial and parallel gradients of density, temperature, electric fields and flow over the divertor volume and therefore, sampling the divertor plasma directly provides crucial knowledge to the interpretation and modeling efforts. Here, we review the contribution of diagnostics that directly sample the plasma to the advancement of knowledge of the physics of detachment and detached divertors, such as the characteristics of the various regimes, discovery and quantification of drifts and identification of convection of heat and particles. We focus on wall probes, scanning probes, retarding field analyzers and Thomson Scattering (TS) in the divertor regionmore » and also include the contribution of measurements away from the divertor that provide insight on how divertor detachment affects core, edge or pedestal conditions. Wall probes are critical as they can be installed in closed volumes of difficult access to other diagnostics and measure plasma parameters at the divertor structures, which define the plasma boundary conditions and where detachment effects are more likely to be strongest.« less

Non-axisymmetric equilibrium reconstruction on the Compact Toroidal Hybrid Experiment using external magnetic and soft x-ray inversion radius measurements

NASA Astrophysics Data System (ADS)

Ma, X.; Cianciosa, M.; Hanson, J. D.; Hartwell, G. J.; Knowlton, S. F.; Maurer, D. A.; Ennis, D. A.; Herfindal, J. L.

2015-11-01

Non-axisymmetric free-boundary equilibrium reconstructions of stellarator plasmas are performed for discharges in which the magnetic configuration is strongly modified by the driven plasma current. Studies were performed on the Compact Toroidal Hybrid device using the V3FIT reconstruction code incorporating a set of 50 magnetic diagnostics external to the plasma, combined with information from soft X-ray (SXR) arrays. With the assumption of closed magnetic flux surfaces, the reconstructions using external magnetic measurements allow accurate estimates of the net toroidal flux within the last closed flux surface, the edge safety factor, and the outer boundary of these highly non-axisymmetric plasmas. The inversion radius for sawtoothing plasmas is used to identify the location of the q = 1 surface, and thus infer the current profile near the magnetic axis. With external magnetic diagnostics alone, we find the reconstruction to be insufficiently constrained. This work is supported by US Department of Energy Grant No. DE-FG02-00ER54610.

A review of direct experimental measurements of detachment

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

Boedo, J.; McLean, A. G.; Rudakov, D. L.

Detached divertor plasmas feature strong radial and parallel gradients of density, temperature, electric fields and flow over the divertor volume and therefore, sampling the divertor plasma directly provides crucial knowledge to the interpretation and modeling efforts. Here, we review the contribution of diagnostics that directly sample the plasma to the advancement of knowledge of the physics of detachment and detached divertors, such as the characteristics of the various regimes, discovery and quantification of drifts and identification of convection of heat and particles. We focus on wall probes, scanning probes, retarding field analyzers and Thomson Scattering (TS) in the divertor regionmore » and also include the contribution of measurements away from the divertor that provide insight on how divertor detachment affects core, edge or pedestal conditions. Wall probes are critical as they can be installed in closed volumes of difficult access to other diagnostics and measure plasma parameters at the divertor structures, which define the plasma boundary conditions and where detachment effects are more likely to be strongest.« less

Implementation of the new multichannel X-mode edge density profile reflectometer for the ICRF antenna on ASDEX Upgrade

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

Aguiam, D. E., E-mail: daguiam@ipfn.tecnico.ulisboa.pt; Silva, A.; Carvalho, P. J.

A new multichannel frequency modulated continuous-wave reflectometry diagnostic has been successfully installed and commissioned on ASDEX Upgrade to measure the plasma edge electron density profile evolution in front of the Ion Cyclotron Range of Frequencies (ICRF) antenna. The design of the new three-strap ICRF antenna integrates ten pairs (sending and receiving) of microwave reflectometry antennas. The multichannel reflectometer can use three of these to measure the edge electron density profiles up to 2 × 10{sup 19} m{sup −3}, at different poloidal locations, allowing the direct study of the local plasma layers in front of the ICRF antenna. ICRF power coupling,more » operational effects, and poloidal variations of the plasma density profile can be consistently studied for the first time. In this work the diagnostic hardware architecture is described and the obtained density profile measurements were used to track outer radial plasma position and plasma shape.« less

A review of direct experimental measurements of detachment

NASA Astrophysics Data System (ADS)

Boedo, J.; McLean, A. G.; Rudakov, D. L.; Watkins, J. G.

2018-04-01

Detached divertor plasmas feature strong radial and parallel gradients of density, temperature, electric fields and flow over the divertor volume and therefore, sampling the divertor plasma directly provides crucial knowledge to the interpretation and modeling efforts. We review the contribution of diagnostics that directly sample the plasma to the advancement of knowledge of the physics of detachment and detached divertors, such as the characteristics of the various regimes, discovery and quantification of drifts and identification of convection of heat and particles. We focus on wall probes, scanning probes, retarding field analyzers and Thomson scattering in the divertor region and also include the contribution of measurements away from the divertor that provide insight on how divertor detachment affects core, edge or pedestal conditions. Wall probes are critical as they can be installed in closed volumes of difficult access to other diagnostics and measure plasma parameters at the divertor structures, which define the plasma boundary conditions and where detachment effects are more likely to be strongest.

Microwave frequency sweep interferometer for plasma density measurements in ECR ion sources: Design and preliminary results

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

Torrisi, Giuseppe; University Mediterranea of Reggio Calabria, Reggio Calabria; Mascali, David

2016-02-15

The Electron Cyclotron Resonance Ion Sources (ECRISs) development is strictly related to the availability of new diagnostic tools, as the existing ones are not adequate to such compact machines and to their plasma characteristics. Microwave interferometry is a non-invasive method for plasma diagnostics and represents the best candidate for plasma density measurement in hostile environment. Interferometry in ECRISs is a challenging task mainly due to their compact size. The typical density of ECR plasmas is in the range 10{sup 11}–10{sup 13} cm{sup −3} and it needs a probing beam wavelength of the order of few centimetres, comparable to the chambermore » radius. The paper describes the design of a microwave interferometer developed at the LNS-INFN laboratories based on the so-called “frequency sweep” method to filter out the multipath contribution in the detected signals. The measurement technique and the preliminary results (calibration) obtained during the experimental tests will be presented.« less

Kinetic Description of the Impedance Probe

NASA Astrophysics Data System (ADS)

Oberrath, Jens; Lapke, Martin; Mussenbrock, Thomas; Brinkmann, Ralf

2011-10-01

Active plasma resonance spectroscopy is a well known diagnostic method. Many concepts of this method are theoretically investigated and realized as a diagnostic tool, one of which is the impedance probe (IP). The application of such a probe in plasmas with pressures of a few Pa raises the question whether kinetic effects have to be taken into account or not. To address this question a kinetic model is necessary. A general kinetic model for an electrostatic concept of active plasma spectroscopy was presented by R.P. Brinkmann and can be used to describe the multipole resonance probe (MRP). In principle the IP is interpretable as a special case of the MRP in lower order. Thus, we are able to describe the IP by the kinetic model of the MRP. Based on this model we derive a solution to investigate the influence of kinetic effects to the resonance behavior of the IP. Active plasma resonance spectroscopy is a well known diagnostic method. Many concepts of this method are theoretically investigated and realized as a diagnostic tool, one of which is the impedance probe (IP). The application of such a probe in plasmas with pressures of a few Pa raises the question whether kinetic effects have to be taken into account or not. To address this question a kinetic model is necessary. A general kinetic model for an electrostatic concept of active plasma spectroscopy was presented by R.P. Brinkmann and can be used to describe the multipole resonance probe (MRP). In principle the IP is interpretable as a special case of the MRP in lower order. Thus, we are able to describe the IP by the kinetic model of the MRP. Based on this model we derive a solution to investigate the influence of kinetic effects to the resonance behavior of the IP. The authors acknowledge the support by the Deutsche Forschungsgemeinschaft (DFG) via the Ruhr University Research School and the Federal Ministry of Education and Research in frame of the PluTO project.

Nonperturbative measurement of the local magnetic field using pulsed polarimetry for fusion reactor conditions (invited)a)

NASA Astrophysics Data System (ADS)

Smith, Roger J.

2008-10-01

A novel diagnostic technique for the remote and nonperturbative sensing of the local magnetic field in reactor relevant plasmas is presented. Pulsed polarimetry [Patent No. 12/150,169 (pending)] combines optical scattering with the Faraday effect. The polarimetric light detection and ranging (LIDAR)-like diagnostic has the potential to be a local Bpol diagnostic on ITER and can achieve spatial resolutions of millimeters on high energy density (HED) plasmas using existing lasers. The pulsed polarimetry method is based on nonlocal measurements and subtle effects are introduced that are not present in either cw polarimetry or Thomson scattering LIDAR. Important features include the capability of simultaneously measuring local Te, ne, and B∥ along the line of sight, a resiliency to refractive effects, a short measurement duration providing near instantaneous data in time, and location for real-time feedback and control of magnetohydrodynamic (MHD) instabilities and the realization of a widely applicable internal magnetic field diagnostic for the magnetic fusion energy program. The technique improves for higher neB∥ product and higher ne and is well suited for diagnosing the transient plasmas in the HED program. Larger devices such as ITER and DEMO are also better suited to the technique, allowing longer pulse lengths and thereby relaxing key technology constraints making pulsed polarimetry a valuable asset for next step devices. The pulsed polarimetry technique is clarified by way of illustration on the ITER tokamak and plasmas within the magnetized target fusion program within present technological means.

Coronal and Prominence Plasmas

NASA Technical Reports Server (NTRS)

Poland, Arthur I. (Editor)

1986-01-01

Various aspects of solar prominences and the solar corona are discussed. The formation of prominences, prominence diagnostics and structure, prominence dissappearance, large scale coronal structure, coronal diagnostics, small scale coronal structure, and non-equilibrium/coronal heating are among the topics covered.

Filterscope diagnostic system on the Experimental Advanced Superconducting Tokamak (EAST)

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

Xu, Z.; Wu, C. R.; Yao, X. J.

2016-11-15

A filterscope diagnostic system has been mounted to observe the line emission and visible bremsstrahlung emission from plasma on the experimental advanced superconducting tokamak during the 2014 campaign. By this diagnostic system, multiple wavelengths including D{sub α} (656.1 nm), D{sub γ} (433.9 nm), He II (468.5 nm), Li I (670.8 nm), Li II (548.3 nm), C III (465.0 nm), O II (441.5 nm), Mo I (386.4 nm), W I (400.9 nm), and visible bremsstrahlung radiation (538.0 nm) are monitored with corresponding wavelength filters. All these multi-channel signals are digitized at up to 200 kHz simultaneously. This diagnostic plays a crucialmore » role in studying edge localized modes and H-mode plasmas, due to the high temporal resolution and spatial resolution that have been designed into it.« less

Large Volume Non-Equilibrium Air Plasma at Atmospheric Pressure: A Novel Method with Low Power Requirements

DTIC Science & Technology

2007-02-28

of magnitude in size. Also unlike corona -like devices such as the plasma needle , which generates 2-3 mm long plasma at the tip of a sharp wire...Distribution Unlimited Table of Contents Abstract AC System with Water Electrode Current voltage characteristics Plasma diagnostics results Experimental setup...Laroussi, PI. 4 AC SYSTEM WITH WATER ELECTRODE Recently, non-equilibrium atmospheric pressure plasmas have been used in a variety of material processing

Study on re-sputtering during CN{sub x} film deposition through spectroscopic diagnostics of plasma

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

Liang, Peipei; Yang, Xu; Li, Hui

2015-10-15

A nitrogen-carbon plasma was generated during the deposition of carbon nitride (CN{sub x}) thin films by pulsed laser ablation of a graphite target in a discharge nitrogen plasma, and the optical emission of the generated nitrogen-carbon plasma was measured for the diagnostics of the plasma and the characterization of the process of CN{sub x} film deposition. The nitrogen-carbon plasma was recognized to contain various species including nitrogen molecules and molecular ions excited in the ambient N{sub 2} gas, carbon atoms and atomic ions ablated from the graphite target and CN radicals. The temporal evolution and spatial distribution of the CNmore » emission and their dependence on the substrate bias voltage show two groups of CN radicals flying in opposite directions. One represents the CN radicals formed as the products of the reactions occurring in the nitrogen-carbon plasma, revealing the reactive deposition of CN{sub x} film due to the reactive expansion of the ablation carbon plasma in the discharge nitrogen plasma and the effective formation of gaseous CN radicals as precursors for CN{sub x} film growth. The other one represents the CN radicals re-sputtered from the growing CN{sub x} film by energetic plasma species, evidencing the re-sputtering of the growing film accompanying film growth. And, the re-sputtering presents ion-induced sputtering features.« less

A High-Efficiency Superhydrophobic Plasma Separator

PubMed Central

Liu, Changchun; Liao, Shih-Chuan; Song, Jinzhao; Mauk, Michael G.; Li, Xuanwen; Wu, Gaoxiang; Ge, Dengteng; Greenberg, Robert M.; Yang, Shu; Bau, Haim H.

2016-01-01

To meet stringent limit-of-detection specifications for low abundance target molecules, a relatively large volume of plasma is needed for many blood-based clinical diagnostics. Conventional centrifugation methods for plasma separation are not suitable for on-site testing or bedside diagnostics. Here, we report a simple, yet high-efficiency, clamshell-style, superhydrophobic plasma separator that is capable of separating a relatively large volume of plasma from several hundred microliters of whole blood (finger-prick blood volume). The plasma separator consists of a superhydrophobic top cover with a separation membrane and a superhydrophobic bottom substrate. Unlike previously reported membrane-based plasma separators, the separation membrane in our device is positioned at the top of the sandwiched whole blood film to increase the membrane separation capacity and plasma yield. In addition, the device’s superhydrophobic characteristics (i) facilitates the formation of well-defined, contracted, thin blood film with a high contact angle; (ii) minimizes biomolecular adhesion to surfaces; (iii) increases blood clotting time; and (iv) reduces blood cell hemolysis. The device demonstrated a “blood in-plasma out” capability, consistently extracting 65±21.5 μL of plasma from 200 μL of whole blood in less than 10 min without electrical power. The device was used to separate plasma from Schistosoma mansoni genomic DNA-spiked whole blood with a recovery efficiency of > 84.5 ± 25.8 %. The S. mansoni genomic DNA in the separated plasma was successfully tested on our custom-made microfluidic chip by using loop mediated isothermal amplification (LAMP) method. PMID:26732765

Low pressure characteristics of the multipole resonance probe

NASA Astrophysics Data System (ADS)

Brinkmann, Ralf Peter; Oberrath, Jens

2014-10-01

The term ``Active plasma resonance spectroscopy'' (APRS) denotes a class of related techniques which utilize, for diagnostic purposes, the natural ability of plasmas to resonate on or near the electron plasma frequency ωpe. The basic idea dates back to the early days of discharge physics but has recently found renewed interest as an approach to industry-compatible plasma diagnostics: A radio frequent signal (in the GHz range) is coupled into the plasma via an antenna or probe, the spectral response is recorded (with the same or another antenna or probe), and a mathematical model is used to determine plasma parameters like the electron density or the electron temperature. When the method is applied to low pressure plasmas (of a few Pa and lower), kinetic effects must be accounted for in the mathematical model. This contribution studies a particular realization of the APRS scheme, the geometrically and electrically symmetric Multipole Resonance Probe (MRP). It is shown that the resonances of the MRP exhibit a residual damping in the limit p --> 0 which cannot be explained by Ohmic dissipation but only by kinetic effects. Supported by the German Federal Ministry of Education and Research (BMBF) in the framework of the PluTO project.

Diagnostic techniques in thermal plasma processing, part 2, volume 2

NASA Astrophysics Data System (ADS)

Boulos, M.; Fauchais, P.; Pfender, E.

1986-02-01

Techniques for diagnostics for thermal plasmas are discussed. These include both optical techniques and in-flight measurements of particulate matter. In the core of the plasma, collisional excitation of the various chemical species is so strong that the population of the corresponding quantum levels becomes high enough for net emission from the plasma. In that case, the classical methods of emission spectroscopy may be applied. But in the regions where the temperatures are below 4000K (these regions are of primary importance for plasma processing), the emission from the plasma is no longer sufficient for emission spectroscopy. In this situation, the population of excited levels must be increased by the absorption of the light from an external source. Such sources, as for example pulsed tunable dye lasers, are now commercially available. The use of such new devices leads to various techniques such as laser induced fluorescence (LIF) or Coherent Anti Stockes Raman Spectroscopy (CARS) that can be used for analyzing plasmas. Particle velocity measurements can be achieved by photography and laser Doppler anemometry. Particle flux measurements are typically achieved by collecting particles on a substrate. Particle size measurements are based on intensity of scattered light.

Study of Stark broadening of Li I 460 and 497 nm spectral lines with independent plasma diagnostics by Thomson scattering

NASA Astrophysics Data System (ADS)

Dzierżȩga, Krzysztof; Piȩta, Tomasz; Zawadzki, Witold; Stambulchik, Evgeny; Gavrilović-Božović, Marijana; Jovićević, Sonja; Pokrzywka, Bartłomiej

2018-02-01

We present results of experimental and theoretical studies of the Stark broadening of the Li I 460 nm spectral line with forbidden components and of the isolated 497 nm line. Plasma was induced by Nd:YAG laser radiation at 1064 nm with pulse duration ˜4.5 ns. Laser-induced plasma was generated in front of the alumina pellet, with some content of Li2CO3, placed in a vacuum chamber filled with argon under reduced pressure. Plasma diagnostics was performed using the laser Thomson scattering technique, free from assumptions about the plasma equilibrium state and its composition and so independently of plasma emission spectra. Spatially resolved spectra with Li lines were obtained from the measured, laterally integrated ones applying the inverse Abel transform. The Stark profiles were calculated by computer simulation method assuming a plasma in the local thermodynamic equilibrium. Calculations were performed for experimentally-inferred electron densities and temperatures, from 1.422 × 1023 to 3.55 × 1022 m-3 and from 1.96 eV to 1.04 eV, respectively. Our studies show very good agreement between experimental Stark profiles and those computer simulated.

Perspective: The physics, diagnostics, and applications of atmospheric pressure low temperature plasma sources used in plasma medicine

NASA Astrophysics Data System (ADS)

Laroussi, M.; Lu, X.; Keidar, M.

2017-07-01

Low temperature plasmas have been used in various plasma processing applications for several decades. But it is only in the last thirty years or so that sources generating such plasmas at atmospheric pressure in reliable and stable ways have become more prevalent. First, in the late 1980s, the dielectric barrier discharge was used to generate relatively large volume diffuse plasmas at atmospheric pressure. Then, in the early 2000s, plasma jets that can launch cold plasma plumes in ambient air were developed. Extensive experimental and modeling work was carried out on both methods and much of the physics governing such sources was elucidated. Starting in the mid-1990s, low temperature plasma discharges have been used as sources of chemically reactive species that can be transported to interact with biological media, cells, and tissues and induce impactful biological effects. However, many of the biochemical pathways whereby plasma affects cells remain not well understood. This situation is changing rather quickly because the field, known today as "plasma medicine," has experienced exponential growth in the last few years thanks to a global research community that engaged in fundamental and applied research involving the use of cold plasma for the inactivation of bacteria, dental applications, wound healing, and the destruction of cancer cells/tumors. In this perspective, the authors first review the physics as well as the diagnostics of the principal plasma sources used in plasma medicine. Then, brief descriptions of their biomedical applications are presented. To conclude, the authors' personal assessment of the present status and future outlook of the field is given.

Characterization and classification of lupus patients based on plasma thermograms

PubMed Central

Chaires, Jonathan B.; Mekmaysy, Chongkham S.; DeLeeuw, Lynn; Sivils, Kathy L.; Harley, John B.; Rovin, Brad H.; Kulasekera, K. B.; Jarjour, Wael N.

2017-01-01

Objective Plasma thermograms (thermal stability profiles of blood plasma) are being utilized as a new diagnostic approach for clinical assessment. In this study, we investigated the ability of plasma thermograms to classify systemic lupus erythematosus (SLE) patients versus non SLE controls using a sample of 300 SLE and 300 control subjects from the Lupus Family Registry and Repository. Additionally, we evaluated the heterogeneity of thermograms along age, sex, ethnicity, concurrent health conditions and SLE diagnostic criteria. Methods Thermograms were visualized graphically for important differences between covariates and summarized using various measures. A modified linear discriminant analysis was used to segregate SLE versus control subjects on the basis of the thermograms. Classification accuracy was measured based on multiple training/test splits of the data and compared to classification based on SLE serological markers. Results Median sensitivity, specificity, and overall accuracy based on classification using plasma thermograms was 86%, 83%, and 84% compared to 78%, 95%, and 86% based on a combination of five antibody tests. Combining thermogram and serology information together improved sensitivity from 78% to 86% and overall accuracy from 86% to 89% relative to serology alone. Predictive accuracy of thermograms for distinguishing SLE and osteoarthritis / rheumatoid arthritis patients was comparable. Both gender and anemia significantly interacted with disease status for plasma thermograms (p<0.001), with greater separation between SLE and control thermograms for females relative to males and for patients with anemia relative to patients without anemia. Conclusion Plasma thermograms constitute an additional biomarker which may help improve diagnosis of SLE patients, particularly when coupled with standard diagnostic testing. Differences in thermograms according to patient sex, ethnicity, clinical and environmental factors are important considerations for application of thermograms in a clinical setting. PMID:29149219

Thruster Plume Plasma Diagnostics: A Ground Chamber Experiment for a 2-Kilowatt Arcjet

NASA Technical Reports Server (NTRS)

Galofaro, Joel T.; Vayner, Boris V.; Hillard, G. Barry; Chornak, Michael T.

2005-01-01

Although detailed near field (0 to 3 cm) information regarding the exhaust plume of a two kilowatt arc jet is available (refs. 1 to 6), there is virtually little or no information (outside of theoretical extrapolations) available concerning the far field (2.6 to 6.1 m). Furthermore real information about the plasma at distances between (3 to 6 m) is of critical importance to high technology satellite companies in understanding the effect of arc jet plume exhausts on space based power systems. It is therefore of utmost importance that one understands the exact nature of the interaction between the arc jet plume, the spacecraft power system and the surrounding electrical plasma environment. A good first step in understanding the nature of the interactions lies in making the needed plume parameter measurements in the far field. All diagnostic measurements are performed inside a large vacuum system (12 m diameter by 18 m high) with a full scale arc jet and solar array panel in the required flight configuration geometry. Thus, necessary information regarding the plume plasma parameters in the far field is obtained. Measurements of the floating potential, the plasma potential, the electron temperature, number density, density distribution, debye length, and plasma frequency are obtained at various locations about the array (at vertical distances from the arc jet nozzle: 2.6, 2.7, 2.8, 3.2, 3.6, 4.0, 4.9, 5.0, 5.4, 5.75, and 6.14 m). Plasma diagnostic parameters are measured for both the floating and grounded configurations of the arc jet anode and array. Spectroscopic optical measurements are then acquired in close proximity to the nozzle, and contamination measurements are made in the vicinity of the array utilizing a mass spectrometer and two Quartz Crystal Microbalances (QCM's).

Circulating Plasma Levels of MicroRNA-21 and MicroRNA-221 Are Potential Diagnostic Markers for Primary Intrahepatic Cholangiocarcinoma

PubMed Central

Kemeny, Nancy; Kingham, T. Peter; Allen, Peter J.; D’Angelica, Michael I.; DeMatteo, Ronald P.; Betel, Doron; Klimstra, David; Jarnagin, William R.; Ventura, Andrea

2016-01-01

Background MicroRNAs (miRNAs) are potential biomarkers in various malignancies. We aim to characterize miRNA expression in intrahepatic cholangiocarcinoma (ICC) and identify circulating plasma miRNAs with potential diagnostic and prognostic utility. Methods Using deep-sequencing techniques, miRNA expression between tumor samples and non-neoplastic liver parenchyma were compared. Overexpressed miRNAs were measured in plasma from an independent cohort of patients with cholangiocarcinoma using RT-qPCR and compared with that healthy volunteers. The discriminatory ability of the evaluated plasma miRNAs between patients and controls was evaluated with receiving operating characteristic (ROC) curves. Results Small RNAs from 12 ICC and 11 tumor-free liver samples were evaluated. Unsupervised hierarchical clustering using the miRNA expression data showed clear grouping of ICC vs. non-neoplastic liver parenchyma. We identified 134 down-regulated and 128 upregulated miRNAs. Based on overexpression and high fold-change, miR21, miR200b, miR221, and miR34c were measured in plasma from an independent cohort of patients with ICC (n = 25) and healthy controls (n = 7). Significant overexpression of miR-21 and miR-221 was found in plasma from ICC patients. Furthermore, circulating miR-21 demonstrated a high discriminatory ability between patients with ICC and healthy controls (AUC: 0.94). Conclusion Among the differentially expressed miRNAs in ICC, miR-21 and miR-221 are overexpressed and detectable in the circulation. Plasma expression levels of these miRNAs, particularly miR-21, accurately differentiates patients with ICC from healthy controls and could potentially serve as adjuncts in diagnosis. Prospective validation and comparison with other hepatobiliary malignancies is required to establish their potential role as diagnostic and prognostic biomarkers. PMID:27685844

Stray light analysis for the Thomson scattering diagnostic of the ETE Tokamak.

PubMed

Berni, L A; Albuquerque, B F C

2010-12-01

Thomson scattering is a well-established diagnostic for measuring local electron temperature and density in fusion plasma, but this technique is particularly difficult to implement due to stray light that can easily mask the scattered signal from plasma. To mitigate this problem in the multipoint Thomson scattering system implemented at the ETE (Experimento Tokamak Esférico) a detailed stray light analysis was performed. The diagnostic system was simulated in ZEMAX software and scattering profiles of the mechanical parts were measured in the laboratory in order to have near realistic results. From simulation, it was possible to identify the main points that contribute to the stray signals and changes in the dump were implemented reducing the stray light signals up to 60 times.

Optimized and Automated design of Plasma Diagnostics for Additive Manufacture

NASA Astrophysics Data System (ADS)

Stuber, James; Quinley, Morgan; Melnik, Paul; Sieck, Paul; Smith, Trevor; Chun, Katherine; Woodruff, Simon

2016-10-01

Despite having mature designs, diagnostics are usually custom designed for each experiment. Most of the design can be now be automated to reduce costs (engineering labor, and capital cost). We present results from scripted physics modeling and parametric engineering design for common optical and mechanical components found in many plasma diagnostics and outline the process for automated design optimization that employs scripts to communicate data from online forms through proprietary and open-source CAD and FE codes to provide a design that can be sent directly to a printer. As a demonstration of design automation, an optical beam dump, baffle and optical components are designed via an automated process and printed. Supported by DOE SBIR Grant DE-SC0011858.

Magnetic diagnostics for equilibrium reconstructions with eddy currents on the lithium tokamak experiment

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

Schmitt, J. C., E-mail: jschmitt@pppl.gov; Lazerson, S.; Majeski, R.

2014-11-15

The Lithium Tokamak eXperiment is a spherical tokamak with a close-fitting low-recycling wall composed of thin lithium layers evaporated onto a stainless steel-lined copper shell. Long-lived non-axisymmetric eddy currents are induced in the shell and vacuum vessel by transient plasma and coil currents and these eddy currents influence both the plasma and the magnetic diagnostic signals that are used as constraints for equilibrium reconstruction. A newly installed set of re-entrant magnetic diagnostics and internal saddle flux loops, compatible with high-temperatures and lithium environments, is discussed. Details of the axisymmetric (2D) and non-axisymmetric (3D) treatments of the eddy currents and themore » equilibrium reconstruction are presented.« less

Diagnostic and prognostic value of preoperative combined GFAP, IGFBP-2, and YKL-40 plasma levels in patients with glioblastoma.

PubMed

Gállego Pérez-Larraya, Jaime; Paris, Sophie; Idbaih, Ahmed; Dehais, Caroline; Laigle-Donadey, Florence; Navarro, Soledad; Capelle, Laurent; Mokhtari, Karima; Marie, Yannick; Sanson, Marc; Hoang-Xuan, Khê; Delattre, Jean-Yves; Mallet, Alain

2014-12-15

Circulating proteins released by tumor cells have recently been investigated as potential single surrogate biomarkers for glioblastoma multiforme (GBM). The aim of the current hypothesis-generating study was to evaluate the diagnostic and prognostic role of preoperative insulin-like growth factor-binding protein 2 (IGFBP-2), chitinase-3-like protein 1 (YKL-40), and glial fibrillary acidic protein (GFAP) plasma levels in patients with GBM, both as single markers and as a combined profile. Plasma samples from 111 patients with GBM and a subset of 40 patients with nonglial brain tumors were obtained preoperatively. Plasma from 99 healthy controls was also analyzed. IGFBP-2, YKL-40, and GFAP levels were determined using enzyme-linked immunoadsorbent assay tests. Their association with histological and radiological variables was assessed. Circulating levels of all 3 proteins were found to be significantly higher in patients with GBM compared with healthy controls (P < .01). Only YKL-40 and GFAP were found to demonstrate significant differences between patients with GBM and nonglial brain tumors (P = .04). GFAP was undetectable (<0.02 ng/mL) in all patients without GBM. A receiver operating characteristic analysis accounting for a 2-step diagnostic procedure including the 3 biomarkers afforded an area under the curve of 0.77 for differentiating patients with GBM from those with nonglial brain tumors. There was a significant correlation between tumor volume and plasma IGFBP-2 level (Spearman Rho correlation coefficient, 0.22; P = .025) and GFAP (Spearman Rho correlation coefficient, 0.36; P < .001) among patients with GBM. Preoperative plasma IGFBP-2 levels were found to be independently associated with worse overall survival among patients with GBM (hazard ratio, 1.3; P = .05). A combined profile of preoperative IGFBP-2, GFAP, and YKL-40 plasma levels could serve as an additional diagnostic tool for patients with inoperable brain lesions suggestive of GBM. In addition, IGFBP-2 levels appear to constitute an independent prognostic factor in patients with GBM. © 2014 American Cancer Society.

Different Detector Types Used in Plasma Physics Experiment

NASA Astrophysics Data System (ADS)

Balovnev, A. V.; Manokhin, I. L.; Grigoryeva, I. G.; Kostyushin, V. A.; Savelov, A. S.; Salakhutdinov, G. Kh.

2017-12-01

We analyzed the possibility of using different detector types (semiconductor, scintillator, thermoluminescent, nuclear emulsions) for plasma diagnostics. We investigated the main characteristics of such detectors, on the basis of which an X-ray spectrometer complex was created.

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

Groth, M; Ellis, R; Brooks, N

A video camera system is described that measures the spatial distribution of visible line emission emitted from the main scrape-off layer (SOL) of plasmas in the DIII-D tokamak. A wide-angle lens installed on an equatorial port and an in-vessel mirror which intercepts part of the lens view provide simultaneous tangential views of the SOL on the low-field and high-field sides of the plasma's equatorial plane. Tomographic reconstruction techniques are used to calculate the 2-D poloidal profiles from the raw data, and 1-D poloidal profiles simulating chordal views of other optical diagnostics from the 2-D profiles. The 2-D profiles can bemore » compared with SOL plasma simulations; the 1-D profiles with measurements from spectroscopic diagnostics. Sample results are presented which elucidate carbon transport in plasmas with toroidally uniform injection of methane and argon transport in disruption mitigation experiments with massive gas jet injection.« less

Use of the Plasma Spectrum RMS Signal for Arc-Welding Diagnostics.

PubMed

Mirapeix, Jesus; Cobo, Adolfo; Fuentes, Jose; Davila, Marta; Etayo, Juan Maria; Lopez-Higuera, Jose-Miguel

2009-01-01

A new spectroscopic parameter is used in this paper for on-line arc-welding quality monitoring. Plasma spectroscopy applied to welding diagnostics has typically relied on the estimation of the plasma electronic temperature, as there is a known correlation between this parameter and the quality of the seams. However, the practical use of this parameter gives rise to some uncertainties that could provoke ambiguous results. For an efficient on-line welding monitoring system, it is essential to prevent the appearance of false alarms, as well as to detect all the possible defects. In this regard, we propose the use of the root mean square signal of the welding plasma spectra, as this parameter will be proven to exhibit a good correlation with the quality of the resulting seams. Results corresponding to several arc-welding field tests performed on Inconel and titanium specimens will be discussed and compared to non-destructive evaluation techniques.

Kinetic equilibrium reconstruction for the NBI- and ICRH-heated H-mode plasma on EAST tokamak

NASA Astrophysics Data System (ADS)

Zhen, ZHENG; Nong, XIANG; Jiale, CHEN; Siye, DING; Hongfei, DU; Guoqiang, LI; Yifeng, WANG; Haiqing, LIU; Yingying, LI; Bo, LYU; Qing, ZANG

2018-04-01

The equilibrium reconstruction is important to study the tokamak plasma physical processes. To analyze the contribution of fast ions to the equilibrium, the kinetic equilibria at two time-slices in a typical H-mode discharge with different auxiliary heatings are reconstructed by using magnetic diagnostics, kinetic diagnostics and TRANSP code. It is found that the fast-ion pressure might be up to one-third of the plasma pressure and the contribution is mainly in the core plasma due to the neutral beam injection power is primarily deposited in the core region. The fast-ion current contributes mainly in the core region while contributes little to the pedestal current. A steep pressure gradient in the pedestal is observed which gives rise to a strong edge current. It is proved that the fast ion effects cannot be ignored and should be considered in the future study of EAST.

Single element of the matrix source of negative hydrogen ions: Measurements of the extracted currents combined with diagnostics

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

Yordanov, D., E-mail: yordanov@phys.uni-sofia.bg; Lishev, St.; Shivarova, A.

2016-02-15

Combining measurements of the extracted currents with probe and laser-photodetachment diagnostics, the study is an extension of recent tests of factors and gas-discharge conditions stimulating the extraction of volume produced negative ions. The experiment is in a single element of a rf source with the design of a matrix of small-radius inductively driven discharges. The results are for the electron and negative-ion densities, for the plasma potential and for the electronegativity in the vicinity of the plasma electrode as well as for the currents of the extracted negative ions and electrons. The plasma-electrode bias and the rf power have beenmore » varied. Necessity of a high bias to the plasma electrode and stable linear increase of the extracted currents with the rf power are the main conclusions.« less

The minimizing of fluorescence background in Raman optical activity and Raman spectra of human blood plasma.

PubMed

Tatarkovič, Michal; Synytsya, Alla; Šťovíčková, Lucie; Bunganič, Bohuš; Miškovičová, Michaela; Petruželka, Luboš; Setnička, Vladimír

2015-02-01

Raman optical activity (ROA) is inherently sensitive to the secondary structure of biomolecules, which makes it a method of interest for finding new approaches to clinical applications based on blood plasma analysis, for instance the diagnostics of several protein-misfolding diseases. Unfortunately, real blood plasma exhibits strong background fluorescence when excited at 532 nm; hence, measuring the ROA spectra appears to be impossible. Therefore, we established a suitable method using a combination of kinetic quenchers, filtering, photobleaching, and a mathematical correction of residual fluorescence. Our method reduced the background fluorescence approximately by 90%, which allowed speedup for each measurement by an average of 50%. In addition, the signal-to-noise ratio was significantly increased, while the baseline distortion remained low. We assume that our method is suitable for the investigation of human blood plasma by ROA and may lead to the development of a new tool for clinical diagnostics.

Measurement of vertical stability metrics in KSTAR

NASA Astrophysics Data System (ADS)

Hahn, Sang-Hee; Humphreys, D. A.; Mueller, D.; Bak, J. G.; Eidietis, N. W.; Kim, H.-S.; Ko, J. S.; Walker, M. L.; Kstar Team

2017-10-01

The paper summarizes results of multi-year ITPA experiments regarding measurement of the vertical stabilization capability of KSTAR discharges, including most recent measurements at the highest achievable elongation (κ 2.0 - 2.1). The measurements of the open-loop growth rate of VDE (γz) and the maximum controllable vertical displacement (ΔZmax) are done by the release-and-catch method. The dynamics of the vertical movement of the plasma is verified by both relevant magnetic reconstructions and non-magnetic diagnostics. The measurements of γz and ΔZmax were done for different plasma currents, βp, internal inductances, elongations and different configurations of the vessel conductors that surround the plasma as the first wall. Effects of control design choice and diagnostics noise are discussed, and comparison with the axisymmetric plasma response model is given for partial accounting for the measured control capability. This work supported by Ministry of Science, ICT, and Future Planning under KSTAR project.

Technical challenges in the construction of the steady-state stellarator Wendelstein 7-X

NASA Astrophysics Data System (ADS)

Bosch, H.-S.; Wolf, R. C.; Andreeva, T.; Baldzuhn, J.; Birus, D.; Bluhm, T.; Bräuer, T.; Braune, H.; Bykov, V.; Cardella, A.; Durodié, F.; Endler, M.; Erckmann, V.; Gantenbein, G.; Hartmann, D.; Hathiramani, D.; Heimann, P.; Heinemann, B.; Hennig, C.; Hirsch, M.; Holtum, D.; Jagielski, J.; Jelonnek, J.; Kasparek, W.; Klinger, T.; König, R.; Kornejew, P.; Kroiss, H.; Krom, J. G.; Kühner, G.; Laqua, H.; Laqua, H. P.; Lechte, C.; Lewerentz, M.; Maier, J.; McNeely, P.; Messiaen, A.; Michel, G.; Ongena, J.; Peacock, A.; Pedersen, T. S.; Riedl, R.; Riemann, H.; Rong, P.; Rust, N.; Schacht, J.; Schauer, F.; Schroeder, R.; Schweer, B.; Spring, A.; Stäbler, A.; Thumm, M.; Turkin, Y.; Wegener, L.; Werner, A.; Zhang, D.; Zilker, M.; Akijama, T.; Alzbutas, R.; Ascasibar, E.; Balden, M.; Banduch, M.; Baylard, Ch.; Behr, W.; Beidler, C.; Benndorf, A.; Bergmann, T.; Biedermann, C.; Bieg, B.; Biel, W.; Borchardt, M.; Borowitz, G.; Borsuk, V.; Bozhenkov, S.; Brakel, R.; Brand, H.; Brown, T.; Brucker, B.; Burhenn, R.; Buscher, K.-P.; Caldwell-Nichols, C.; Cappa, A.; Cardella, A.; Carls, A.; Carvalho, P.; Ciupiński, Ł.; Cole, M.; Collienne, J.; Czarnecka, A.; Czymek, G.; Dammertz, G.; Dhard, C. P.; Davydenko, V. I.; Dinklage, A.; Drevlak, M.; Drotziger, S.; Dudek, A.; Dumortier, P.; Dundulis, G.; Eeten, P. v.; Egorov, K.; Estrada, T.; Faugel, H.; Fellinger, J.; Feng, Y.; Fernandes, H.; Fietz, W. H.; Figacz, W.; Fischer, F.; Fontdecaba, J.; Freund, A.; Funaba, T.; Fünfgelder, H.; Galkowski, A.; Gates, D.; Giannone, L.; García Regaña, J. M.; Geiger, J.; Geißler, S.; Greuner, H.; Grahl, M.; Groß, S.; Grosman, A.; Grote, H.; Grulke, O.; Haas, M.; Haiduk, L.; Hartfuß, H.-J.; Harris, J. H.; Haus, D.; Hein, B.; Heitzenroeder, P.; Helander, P.; Heller, R.; Hidalgo, C.; Hildebrandt, D.; Höhnle, H.; Holtz, A.; Holzhauer, E.; Holzthüm, R.; Huber, A.; Hunger, H.; Hurd, F.; Ihrke, M.; Illy, S.; Ivanov, A.; Jablonski, S.; Jaksic, N.; Jakubowski, M.; Jaspers, R.; Jensen, H.; Jenzsch, H.; Kacmarczyk, J.; Kaliatk, T.; Kallmeyer, J.; Kamionka, U.; Karaleviciu, R.; Kern, S.; Keunecke, M.; Kleiber, R.; Knauer, J.; Koch, R.; Kocsis, G.; Könies, A.; Köppen, M.; Koslowski, R.; Koshurinov, J.; Krämer-Flecken, A.; Krampitz, R.; Kravtsov, Y.; Krychowiak, M.; Krzesinski, G.; Ksiazek, I.; Kubkowska, M.; Kus, A.; Langish, S.; Laube, R.; Laux, M.; Lazerson, S.; Lennartz, M.; Li, C.; Lietzow, R.; Lohs, A.; Lorenz, A.; Louche, F.; Lubyako, L.; Lumsdaine, A.; Lyssoivan, A.; Maaßberg, H.; Marek, P.; Martens, C.; Marushchenko, N.; Mayer, M.; Mendelevitch, B.; Mertens, Ph.; Mikkelsen, D.; Mishchenko, A.; Missal, B.; Mizuuchi, T.; Modrow, H.; Mönnich, T.; Morizaki, T.; Murakami, S.; Musielok, F.; Nagel, M.; Naujoks, D.; Neilson, H.; Neubauer, O.; Neuner, U.; Nocentini, R.; Noterdaeme, J.-M.; Nührenberg, C.; Obermayer, S.; Offermanns, G.; Oosterbeek, H.; Otte, M.; Panin, A.; Pap, M.; Paquay, S.; Pasch, E.; Peng, X.; Petrov, S.; Pilopp, D.; Pirsch, H.; Plaum, B.; Pompon, F.; Povilaitis, M.; Preinhaelter, J.; Prinz, O.; Purps, F.; Rajna, T.; Récsei, S.; Reiman, A.; Reiter, D.; Remmel, J.; Renard, S.; Rhode, V.; Riemann, J.; Rimkevicius, S.; Riße, K.; Rodatos, A.; Rodin, I.; Romé, M.; Roscher, H.-J.; Rummel, K.; Rummel, Th.; Runov, A.; Ryc, L.; Sachtleben, J.; Samartsev, A.; Sanchez, M.; Sano, F.; Scarabosio, A.; Schmid, M.; Schmitz, H.; Schmitz, O.; Schneider, M.; Schneider, W.; Scheibl, L.; Scholz, M.; Schröder, G.; Schröder, M.; Schruff, J.; Schumacher, H.; Shikhovtsev, I. V.; Shoji, M.; Siegl, G.; Skodzik, J.; Smirnow, M.; Speth, E.; Spong, D. A.; Stadler, R.; Sulek, Z.; Szabó, V.; Szabolics, T.; Szetefi, T.; Szökefalvi-Nagy, Z.; Tereshchenko, A.; Thomsen, H.; Thumm, M.; Timmermann, D.; Tittes, H.; Toi, K.; Tournianski, M.; Toussaint, U. v.; Tretter, J.; Tulipán, S.; Turba, P.; Uhlemann, R.; Urban, J.; Urbonavicius, E.; Urlings, P.; Valet, S.; Van Eester, D.; Van Schoor, M.; Vervier, M.; Viebke, H.; Vilbrandt, R.; Vrancken, M.; Wauters, T.; Weissgerber, M.; Weiß, E.; Weller, A.; Wendorf, J.; Wenzel, U.; Windisch, T.; Winkler, E.; Winkler, M.; Wolowski, J.; Wolters, J.; Wrochna, G.; Xanthopoulos, P.; Yamada, H.; Yokoyama, M.; Zacharias, D.; Zajac, J.; Zangl, G.; Zarnstorff, M.; Zeplien, H.; Zoletnik, S.; Zuin, M.

2013-12-01

The next step in the Wendelstein stellarator line is the large superconducting device Wendelstein 7-X, currently under construction in Greifswald, Germany. Steady-state operation is an intrinsic feature of stellarators, and one key element of the Wendelstein 7-X mission is to demonstrate steady-state operation under plasma conditions relevant for a fusion power plant. Steady-state operation of a fusion device, on the one hand, requires the implementation of special technologies, giving rise to technical challenges during the design, fabrication and assembly of such a device. On the other hand, also the physics development of steady-state operation at high plasma performance poses a challenge and careful preparation. The electron cyclotron resonance heating system, diagnostics, experiment control and data acquisition are prepared for plasma operation lasting 30 min. This requires many new technological approaches for plasma heating and diagnostics as well as new concepts for experiment control and data acquisition.

Use of the Plasma Spectrum RMS Signal for Arc-Welding Diagnostics

PubMed Central

Mirapeix, Jesus; Cobo, Adolfo; Fuentes, Jose; Davila, Marta; Etayo, Juan Maria; Lopez-Higuera, Jose-Miguel

2009-01-01

A new spectroscopic parameter is used in this paper for on-line arc-welding quality monitoring. Plasma spectroscopy applied to welding diagnostics has typically relied on the estimation of the plasma electronic temperature, as there is a known correlation between this parameter and the quality of the seams. However, the practical use of this parameter gives rise to some uncertainties that could provoke ambiguous results. For an efficient on-line welding monitoring system, it is essential to prevent the appearance of false alarms, as well as to detect all the possible defects. In this regard, we propose the use of the root mean square signal of the welding plasma spectra, as this parameter will be proven to exhibit a good correlation with the quality of the resulting seams. Results corresponding to several arc-welding field tests performed on Inconel and titanium specimens will be discussed and compared to non-destructive evaluation techniques. PMID:22346696

[Role of plasma procalcitonin in the diagnosis of ventilator-associated pneumonia: systematic review and metaanalysis].

PubMed

Sotillo-Díaz, J C; Bermejo-López, E; García-Olivares, P; Peral-Gutiérrez, J A; Sancho-González, M; Guerrero-Sanz, J E

2014-01-01

To determine the role of plasma procalcitonin (PCT) levels in diagnosing ventilator-associated pneumonia. A systematic review of publications prospectively assessing the diagnostic role of PCT in ventilator-associated pneumonia was carried out. The search was performed using Medline, Embase, the Cochrane Collaboration and MEDION, with reviewing of the references of retrieved articles. We extracted data that allowed the calculation of sensitivity, specificity, likelihood ratios and diagnostic odds ratio. Intervention Metaregression was performed to determine whether exposure to previous antibiotic treatment, the time to occurrence of ventilator-associated pneumonia and the type of patients had an impact upon the diagnostic performance of procalcitonin. Seven studies were considered (373 patients, 434 episodes). We found no publication bias or threshold effect. High plasma PCT levels were associated to an increased risk of suffering ventilator-associated pneumonia (OR: 8.39; 95% CI: 5.4-12.6). The pooled data on sensitivity, specificity, positive and negative likelihood ratio, and diagnostic odds ratio found were 76% (69-82), 79% (74-84), 4.35 (2.48-7.62), 0.26 (0.15-0.46) and 17.9 (10.1-31.7), respectively. Diagnostic yield was modified by prior exposure to antibiotics (rDOR 0.11, 0.02-0.069), but not by the type of critically ill patient or the time to occurrence of ventilator-associated pneumonia. Our results suggest that PCT provides additional information on the risk of VAP. Inclusion of PCT in diagnostic algorithms could improve their effectiveness. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.

Evaluating the Gifted Students' Understanding Related to Plasma State Using Plasma Experimental System and Two-Tier Diagnostic Test

ERIC Educational Resources Information Center

Korkmaz, Saadet Deniz; Ayas, Bahadir; Aybek, Eren Can; Pat, Suat

2018-01-01

The purpose of this study was to investigate the effectiveness of the experimental system design related to plasma state on the gifted students' understanding on the subject of the plasma state. To test the research hypothesis, one group pretest-posttest research model was carried out with 18 eighth-grade (4 girls and 14 boys) gifted students in…

Spectrometer Development in Support of Thomson Scattering Investigations for the Helicon Plasma Experiment (HPX)

NASA Astrophysics Data System (ADS)

Sandri, Eva; Davies, Richard; Azzari, Phil; Frank, John; Frank, Jackson; James, Royce; Hopson, Jordon; Duke-Tinson, Omar; Paolino, Richard; Sherman, Justin; Wright, Erin; Turk, Jeremy

2016-10-01

Now that reproducible plasmas have been created on the Helicon Plasma Experiment (HPX) at the Coast Guard Academy Plasma Laboratory (CGAPL), a high-performance spectrometer utilizing volume-phase-holographic (VPH) grating and a charge coupled device (CCD) camera with a range of 380-1090 nm and resolution of 1024x1024 is being assembled. This spectrometer will collect doppler shifted photons created by exciting the plasma with the first harmonic of a 2.5 J Nd:YAG laser at a wavelength of 1064 nm. Direct measurements of the plasma's temperature and density will be determined using HPX's Thomson Scattering (TS) system as a single spatial point diagnostic. TS has the capability of determining plasma properties on short time scales and will be used to create a robust picture of the internal plasma parameters. A prototype spectrometer has been constructed to explore the Andor CCD camera's resolution and sensitivity. Concurrently, through intensive study of the high energy TS system, safety protocols and standard operation procedures (SOP) for the Coast Guard's largest and most powerful Laser have been developed. The current status of the TS SOP, diagnostic development, and the collection optic's spectrometer will be reported. Supported by U.S. DEPS Grant [HEL-JTO] PRWJFY15-16.

Understanding the Effect of Gas Dynamics in Plasma Gun Performance for Simulating Fusion Wall Response to Disruption Events

NASA Astrophysics Data System (ADS)

Riedel, Will; Underwood, Thomas; Righetti, Fabio; Cappelli, Mark

2017-10-01

In this work, the suitability of a pulsed coaxial plasma accelerator to simulate the interaction of edge-localized modes with plasma first wall materials is investigated. Experimental measurements derived from a suite of diagnostics are presented that focus on both the properties of the plasma flow and the manner in which such jets couple with material interfaces. Specific emphasis is placed on quantifying the variation in these properties using tungsten tokens exposed to the plasma plume as the gun volume is progressively filled with more neutral gas. These results are mapped to the operational dynamics of the gun via a time-resolved Schlieren cinematic visualization of the density gradient within the flow. Resulting videos indicate the existence of two distinct modes with vastly different characteristic timescales, spatial evolution, and plasma properties. Time resolved quantification of the associated plasma heat flux for both modes, including a range spanning 150 MW m-2 - 10 GW m-2, is presented using both a fast thermocouple gauge and an IR camera. Both diagnostics in conjunction with a heat transfer model provide an accurate description of the energy transfer dynamics and operational characteristics of plasma guns. This work is supported by the U.S. Department of Energy Stewardship Science Academic Program.

ZaP-HD: High Energy Density Z-Pinch Plasmas using Sheared Flow Stabilization

NASA Astrophysics Data System (ADS)

Golingo, R. P.; Shumlak, U.; Nelson, B. A.; Claveau, E. L.; Doty, S. A.; Forbes, E. G.; Hughes, M. C.; Kim, B.; Ross, M. P.; Weed, J. R.

2015-11-01

The ZaP-HD flow Z-pinch project investigates scaling the flow Z-pinch to High Energy Density Plasma, HEDP, conditions by using sheared flow stabilization. ZaP used a single power supply to produce 100 cm long Z-pinches that were quiescent for many radial Alfven times and axial flow-through times. The flow Z-pinch concept provides an approach to achieve HED plasmas, which are dimensionally large and persist for extended durations. The ZaP-HD device replaces the single power supply from ZaP with two separate power supplies to independently control the plasma flow and current in the Z-pinch. Equilibrium is determined by diagnostic measurements of the density with interferometry and digital holography, the plasma flow and temperature with passive spectroscopy, the magnetic field with surface magnetic probes, and plasma emission with optical imaging. The diagnostics fully characterize the plasma from its initiation in the coaxial accelerator, through the pinch, and exhaust from the assembly region. The plasma evolution is modeled with high resolution codes: Mach2, WARPX, and NIMROD. Experimental results and scaling analyses are presented. This work is supported by grants from the U.S. Department of Energy and the U.S. National Nuclear Security Administration.

Singular structure of Mueller matrices images of biological crystal networks for diagnostic human tissues pathological changes

NASA Astrophysics Data System (ADS)

Sakhnovskiy, M. Y.; Ushenko, V. A.

2013-09-01

The process of converting of laser radiation by optically anisotropic crystals of biological networks are singular in the sense of total (simultaneous) of mechanisms of orientation and phase (birefringence) anisotropy the formation of polarization-inhomogeneous field of scattered radiation. This work is aimed at developing a method of polarization selection mechanisms of blood plasma polycrystalline networks anisotropy. The relationship between statistics, correlation and fractal parameters of polarization-inhomogeneous images of blood plasma and by linear dichroism and linear birefringence of polycrystalline networks albumin and globulin was found. The criteria of differentiation and diagnostic images of polarization-inhomogeneous plasma samples of the control group (donor) and a group of patients with malignant changes of breast tissue was identified.

Plasma CVD of Carbon Nanotubes

NASA Technical Reports Server (NTRS)

Delzeit, Lance; Cruden, B.; Hash, D.; Meyyappan, M.; DeVincenzi, Donald L. (Technical Monitor)

2001-01-01

Carbon nanotubes(CNT) exhibit remarkable mechanical and unique electronic properties and thus have created excitement in the research community about their potential in electronics, computing, sensor and structural applications. Realization of these applications critically depends on the ability to control the properties(such as diameter, chirality) as well purity. We have investigated CNT growth using an inductively coupled plasma(ICP) process using hydrocarbon feedstock. The catalyst required for nanotube growth consists of thin sputtered layers of aluminum and iron(10 nm each) and aligned carbon nanotubes have been obtained. Optical emission diagnostics as well as a plasma modeling effort have been undertaken to understand growth mechanisms. This presentation will discuss growth characteristics under various pressure, power and feedgas compositions and our understanding from modeling and diagnostics.

Beam deviation method as a diagnostic tool for the plasma focus.

PubMed

Schmidt, H; Rückle, B

1978-04-15

The application of an optical method for density measurements in cylindrical plasmas is described. The angular deviation of a probing light beam sent through a plasma is proportional to the maximum of the density in the plasma column. The deviation does not depend on the plasma dimensions; however, it is influenced to a certain degree by the density profile. The method is successfully applied to the investigation of a dense plasma focus with a time resolution of 2 nsec and a spatial resolution (in axial direction) of 2 mm.

Plasma neutrophil gelatinase-associated lipocalin: a marker of acute pyelonephritis in children.

PubMed

Kim, Byung Kwan; Yim, Hyung Eun; Yoo, Kee Hwan

2017-03-01

This study was designed to compare the diagnostic accuracy of plasma neutrophil gelatinase-associated lipocalin (NGAL) with procalcitonin (PCT), C-reactive protein (CRP), and white blood cells (WBCs) for predicting acute pyelonephritis (APN) in children with febrile urinary tract infections (UTIs). In total, 138 children with febrile UTIs (APN 59, lower UTI 79) were reviewed retrospectively. Levels of NGAL, PCT, CRP, and WBCs in blood were measured on admission. The diagnostic accuracy of the biomarkers was investigated. Independent predictors of APN were identified by multivariate logistic regression analysis. Receiver operating curve (ROC) analyses showed good diagnostic profiles of NGAL, PCT, CRP, and WBCs for identifying APN [area under the curve (AUC) 0.893, 0.855, 0.879, and 0.654, respectively]. However, multivariate analysis revealed only plasma NGAL level was an independent predictor of APN (P = 0.006). At the best cutoff values of all examined biomarkers for identifying APN, sensitivity (86 %), specificity (85 %), positive predictive value (81 %), and negative predictive value (89 %) of plasma NGAL levels were the highest. The optimal NGAL cutoff value was 117 ng/ml. The positive likelihood ratio [odds ratio (OR) 5.69, 95 % confidence interval (CI) 3.56-8.78], and negative likelihood ratio (OR 0.16, 95 % CI 0.08-0.29) of plasma NGAL for APN diagnosis also showed it seemed to be more accurate than serum PCT, CRP, and WBCs. Plasma NGAL can be more useful than serum PCT, CRP, and WBC levels for identifying APN in children with febrile UTIs.

Stark width and shift for electron number density diagnostics of low temperature plasma: Application to silicon Laser Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

Ivković, M.; Konjević, N.

2017-05-01

In this work we summarize, analyze and critically evaluate experimental procedures and results of LIBS electron number density plasma characterization using as examples Stark broadened Si I and Si II line profiles. Selected publications are covering the time period from very beginning of silicon LIBS studies until the end of the year 2015. To perform the analysis of experimental LIBS data, the testing of available semiclassical theoretical Stark broadening parameters for Si I and Si II lines was accomplished first. This is followed by the description of experimental setups, results and details of experimental procedure relevant for the line shape analysis of spectral lines used for plasma characterization. Although most of results and conclusions of this analysis are related to the application of silicon lines for LIBS characterization they are of general importance and may be applied to other elements and different low-temperature plasma sources. The analysis of experimental procedures used for LIBS diagnostics from emission profiles of non-hydrogenic spectral lines is carried out in the following order: the influence of laser ablation and crater formation, spatial and temporal plasma observation, line self-absorption and experimental profile deconvolution, the contribution of ion broadening in comparison with electron impacts contributions to the line width in case of neutral atom line and some other aspects of line shape analysis are considered. The application of Stark shift for LIBS diagnostics is demonstrated and discussed. Finally, the recommendations for an improvement of experimental procedures for LIBS electron number density plasma characterization are offered.

Development of Methods for Diagnostics of Discharges in Supersonic Flows

DTIC Science & Technology

2001-09-01

probe. As it was carried out in [I.21] the calculations of equilibrium structure of combustion products of hydrocarbonaceous fuel have shown, that at...fiber line for the required distance and the inverse transformation of the digit code to the analogue signal. New methods of plasma diagnostics are...plasma …. 137 2.3.1 Non-stationary kinetic model of a discharge in a dry air ………………………………………... 140 2.3.2 Results of numerical calculations of gas

Spatial and temporal analysis of DIII-D 3D magnetic diagnostic data

DOE PAGES

Strait, E. J.; King, J. D.; Hanson, J. M.; ...

2016-08-11

An extensive set of magnetic diagnostics in DIII-D is aimed at measuring non-axisymmetric "3D" features of tokamak plasmas, with typical amplitudes ~10 -3 to 10 -5 of the total magnetic field. We describe hardware and software techniques used at DIII-D to condition the individual signals and analysis to estimate the spatial structure from an ensemble of discrete measurements. Lastly, applications of the analysis include detection of non-rotating MHD instabilities, plasma control, and validation of MHD stability and 3D equilibrium models.

Optical diagnostics of the arc plasma using fast intensified CCD-spectrograph system

NASA Astrophysics Data System (ADS)

Pavelescu, Gabriela; Guillot, Stephane; Braic, Mariana T.; Hong, Dunpin; Pavelescu, D.; Fleurier, Claude; Braic, Viorel; Gherendi, F.; Dumitrescu, G.; Anghelita, P.; Bauchire, J. M.

2004-10-01

Spectroscopic diagnostics, using intensified high speed CCD camera, was applied to study the arc dynamics in low voltage circuit breakers, in vacuum and in air. Time-resolved emission spectroscopy of the vacuum arc plasma, generated during electrode separation, provided information about the interruption process. The investigations were focused on the partial unsuccessful interruption around current zero. Absorption spectroscopy, in a peculiar setup, was used in order to determine the metallic atoms densities in the interelectrode space of a low voltage circuit breaker, working in ambient air.

Characteristics of switching plasma in an inverse-pinch switch

NASA Technical Reports Server (NTRS)

Lee, Ja H.; Choi, Sang H.; Venable, Demetrius D.; Han, Kwang S.; Nam, Sang H.

1993-01-01

Characteristics of the plasma that switches on tens of giga volt-ampere in an inverse-pinch plasma switch (INPIStron) have been made. Through optical and spectroscopic diagnostics of the current carrying plasma, the current density, the motion of current paths, dominant ionic species have been determined in order to access their effects on circuit parameters and material erosion. Also the optimum operational condition of the plasma-puff triggering method required for azimuthally uniform conduction in the INPIStron has been determined.

An Experimental Study of the Plasma Focus Device as a Charged Particle Accelerator

DTIC Science & Technology

1988-11-01

The dense plasma focus has been investigated at many laboratories as a possible fusion device. Typical plasma parameters for this device are electron...temperatures of 1 keV, densities of 10 to the 19th power per cc, and confinement times of 100 ns. Characteristic of the plasma focus discharge are...neutrons. The emphasis of this work is to investigate the electron and ion emission from the plasma focus and the development of appropriate diagnostics to

Secure web-based invocation of large-scale plasma simulation codes

NASA Astrophysics Data System (ADS)

Dimitrov, D. A.; Busby, R.; Exby, J.; Bruhwiler, D. L.; Cary, J. R.

2004-12-01

We present our design and initial implementation of a web-based system for running, both in parallel and serial, Particle-In-Cell (PIC) codes for plasma simulations with automatic post processing and generation of visual diagnostics.

New advanced netted ground based and topside radio diagnostics for Space Weather Program

NASA Astrophysics Data System (ADS)

Rothkaehl, Hanna; Krankowski, Andrzej; Morawski, Marek; Atamaniuk, Barbara; Zakharenkova, Irina; Cherniak, Iurii

2014-05-01

To give a more detailed and complete understanding of physical plasma processes that govern the solar-terrestrial space, and to develop qualitative and quantitative models of the magnetosphere-ionosphere-thermosphere coupling, it is necessary to design and build the next generation of instruments for space diagnostics and monitoring. Novel ground- based wide-area sensor networks, such as the LOFAR (Low Frequency Array) radar facility, comprising wide band, and vector-sensing radio receivers and multi-spacecraft plasma diagnostics should help solve outstanding problems of space physics and describe long-term environmental changes. The LOw Frequency ARray - LOFAR - is a new fully digital radio telescope designed for frequencies between 30 MHz and 240 MHz located in Europe. The three new LOFAR stations will be installed until summer 2015 in Poland. The LOFAR facilities in Poland will be distributed among three sites: Lazy (East of Krakow), Borowiec near Poznan and Baldy near Olsztyn. All they will be connected via PIONIER dedicated links to Poznan. Each site will host one LOFAR station (96 high-band+96 low-band antennas). They will most time work as a part of European network, however, when less charged, they can operate as a national network The new digital radio frequency analyzer (RFA) on board the low-orbiting RELEC satellite was designed to monitor and investigate the ionospheric plasma properties. This two-point ground-based and topside ionosphere-located space plasma diagnostic can be a useful new tool for monitoring and diagnosing turbulent plasma properties. The RFA on board the RELEC satellite is the first in a series of experiments which is planned to be launched into the near-Earth environment. In order to improve and validate the large scales and small scales ionospheric structures we will used the GPS observations collected at IGS/EPN network employed to reconstruct diurnal variations of TEC using all satellite passes over individual GPS stations and the data retrieved from FORMOSAT-3/COSMIC radio occultation measurements. The main purpose of this presentation is to describe new advanced diagnostic techniques of the near-Earth space plasma and point out the scientific challenges of the radio frequency analyser located on board of low orbiting satellites and LOFAR facilities. This research is partly supported by grant O N517 418440

Plasma Radiation Source Development Program

DTIC Science & Technology

2006-03-01

shell mass distributions perform belter than thin shells. The dual plenum, double shell load has unique diagnostic features that enhance our...as implosion time increases. 13. SUBJECT TERMS Zpinch x-ray diagnostics Rayleigh-Taylor instability pulsed-power x-ray spectroscopy supersonic...feature permits some very useful diagnostics that shed light on critical details of the implosion process. See Section 3 for details. We have

Development of a sub-cm high resolution ion Doppler tomography diagnostics for fine structure measurement of guide field reconnection in TS-U

NASA Astrophysics Data System (ADS)

Tanabe, Hiroshi; Koike, Hideya; Hatano, Hironori; Hayashi, Takumi; Cao, Qinghong; Himeno, Shunichi; Kaneda, Taishi; Akimitsu, Moe; Sawada, Asuka; Ono, Yasushi

2017-10-01

A new type of high-throughput/high-resolution 96CH ion Doppler tomography diagnostics has been developed using ``multi-slit'' spectroscopy technique for detailed investigation of fine structure formation during high guide field magnetic reconnection. In the last three years, high field merging experiment in MAST pioneered new frontiers of reconnection heating: formation of highly peaked structure around X-point in high guide field condition (Bt > 0.3 T), outflow dissipation under the influence of better plasma confinement to form high temperature ring structure which aligns with closed flux surface of toroidal plasma, and interaction between ion and electron temperature profile during transport/confinement phase to form triple peak structure (τeiE 4 ms). To investigate more detailed mechanism with in-situ magnetic measurement, the university of Tokyo starts the upgrade of plasma parameters and spatial resolution of optical diagnostics as in MAST. Now, a new type of high-throughput/high-resolution 96CH ion Doppler tomography diagnostics system construction has been completed and it successfully resolved fine structure of ion heating downstream, aligned with closed flux surface formed by reconnected field. This work was supported by JSPS KAKENHI Grant Numbers 15H05750, 15K14279 and 17H04863.

Experimental investigation of adiabatic compression and heating using collision of an MHD-driven jet with a gas target cloud for magnetized target fusion

NASA Astrophysics Data System (ADS)

Seo, Byonghoon; Li, Hui; Bellan, Paul

2017-10-01

We are studying magnetized target fusion using an experimental method where an imploding liner compressing a plasma is simulated by a high-speed MHD-driven plasma jet colliding with a gas target cloud. This has the advantage of being non-destructive so orders of magnitude more shots are possible. Since the actual density and temperature are much more modest than fusion-relevant values, the goal is to determine the scaling of the increase in density and temperature when an actual experimental plasma is adiabatically compressed. Two new-developed diagnostics are operating and providing data. The first new diagnostic is a fiber-coupled interferometer which measures line-integrated electron density not only as a function of time, but also as a function of position along the jet. The second new diagnostic is laser Thomson scattering which measures electron density and temperature at the location where the jet collides with the cloud. These diagnostics show that when the jet collides with a target cloud the jet slows down substantially and both the electron density and temperature increase. The experimental measurements are being compared with 3D MHD and hybrid kinetic numerical simulations that model the actual experimental geometry.

First experiment on LMJ facility: pointing and synchronisation qualification, sequences qualification

NASA Astrophysics Data System (ADS)

Henry, Olivier; Raffestin, Didier; Bretheau, Dominique; Luttmann, Michel; Graillot, Herve; Ferri, Michel; Seguineau, Frederic; Bar, Emmanuel; Patissou, Loic; Canal, Philippe; Sautarel, Françoise; Tranquille-Marques, Yves

2015-11-01

The LMJ (Laser mega Joule) facility at the CESTA site (Aquitaine, France) is a tool designed to deliver up to 1.2 MJ at 351 nm. The experiment system will include plasma diagnostics: UV and X energy balances, imagers (Streak and stripe camera, CCD), spectrometers, and a Visar/pyrometer. The facility must be able to deliver, within the hour following the shot, all the results of the plasma diagnostics, alignment images and laser diagnostic measurements. Part of the end of 2014 was devoted to the qualification of system pointing on target and synchronization within and between beams. The shots made with one chain (divided in 2 quads - 8 laser beams) have achieved 50 μm of misalignment accuracy and a synchronization accuracy in the order of 50 ps. The performances achieved for plasma diagnostic (in the order of less 100 μm of alignment and timing accuracy less than 150 ps) comply with expectations. At the same time the first automatic sequences were tested. They allowed a shot on target every 6h:30 and in some case twice a day by reducing preparation actions, leading to a sequence of 4h:00. These shooting sequences are managed by an operating team of 7 people helped by 3 people for security aspects.

First experiment on LMJ facility: pointing and synchronisation qualification

NASA Astrophysics Data System (ADS)

Henry, Olivier; Raffestin, Didier; Bretheau, Dominique; Luttmann, Michel; Graillot, Herve; Ferri, Michel; Seguineau, Frederic; Bar, Emmanuel; Patissou, Loic; Canal, Philippe; Sautarel, Franöise; Tranquille-Marques, Yves

2017-10-01

The LMJ (Laser mega Joule) facility at the CESTA site (Aquitaine, France) is a tool designed to deliver up to 1.2 MJ at 351 nm for plasma experiments. The experiment system will include 11 diagnostics: UV and X energy balances, imagers (Streak and stripe camera, CCD), spectrometers, and a Visar/pyrometer. The facility must be able to deliver, within the hour following the shot, all the results of the plasma diagnostics, alignment images and laser diagnostic measurements. These results have to be guaranteed in terms of conformity to the request and quality of measurement. The end of 2016 was devoted to the qualification of system pointing on target and synchronization within and between beams. The shots made with two chains (divided in 4 quads - 8 laser beams) have achieved 50 µm of misalignment accuracy (chain and quad channel) and a synchronization accuracy in the order of 50 ps . The performances achieved for plasma diagnostic (in the order of less 100 µm of alignment and timing accuracy less than 150 ps) comply with expectations. At the same time the first automatic sequences were tested. They allowed a shot on target every 6h:30 and in some case twice a day by reducing preparation actions, leading to a sequence of 4h:00.

[Spectroscopic diagnostics of DC argon plasma at atmospheric pressure].

PubMed

Tu, Xin; Lu, Sheng-yong; Yan, Jian-hua; Ma, Zeng-yi; Pan, Xin-chao; Cen, Ke-fa; Cheron, Bruno

2006-10-01

The optical emission spectra of DC argon plasma at atmospheric pressure were measured inside and outside the arc chamber. The electron temperature was determined from the Boltzmann plot, and the electron density was derived from Stark broadening of Ar I lines. The criteria for the existence of local thermodynamic equilibrium (LTE)in the plasma was discussed. The results indicate that the DC argon plasma at atmospheric pressure under our experimental conditions is in LTE.

International Workshop on Magneto-Plasma Aerodynamics (8th)

DTIC Science & Technology

2010-05-14

outer conductor of coaxial waveguide. (b) (1 − 3) − different positions of a plasma channel in nonsteady-state plasmatron. The microwave power is...out at MIPT. Nanosecond DBD discharge in a special coaxial geometry of electrodes was used to produce a thin layer of quasi-uniform plasma in the...discharge cell, diagnostics means, high-voltage sources and commutation units. Cell commutation was effected by a plasma gun actuated by a start unit

Plasma cell gingivitis - A rare case related to Colocasia (arbi) leaves.

PubMed

Bali, Deepika; Gill, Sanjeet; Bali, Amit

2012-09-01

Plasma cell gingivitis is an uncommon inflammatory condition of uncertain etiology often flavoured chewing gum, spices, foods, candies, or dentifrices. The diagnosis of plasma cell gingivitis is based on comprehensive history taking, clinical examination, and appropriate diagnostic tests. Here we are presenting a rare case of plasma cell gingivitis caused by consumption of colocasia (arbi) leaves. Colocasia is a kind of vegetable, very commonly consumed in the regions of North India.

Recent Advances in Narrowband Stimulated Electromagnetic Emission NSEE Investigations at HAARP and EISCAT

NASA Astrophysics Data System (ADS)

Scales, Wayne

2016-07-01

Investigation of stimulated radiation, commonly known as Stimulated Electromagnetic Emissions (SEE), produced by the interaction of high-power, High Frequency HF radiowaves with the ionospheric plasma has been a vibrant area of research since the early 1980's. Substantial diagnostic information about ionospheric plasma characteristics, dynamics, and turbulence can be obtained from the frequency spectrum of the stimulated radiation. During the past several decades, so-called wideband SEE (WSEE) which exists in a frequency band of ±100 KHz or so of the transmit wave frequency (which is several MHz) has been investigated relatively thoroughly. Upgrades both in transmitter power and diagnostic receiver frequency sensitivity at major ionosphere interaction facilities (i.e. HAARP and EISCAT) have allowed new breakthroughs in the ability to study a plethora of processes associated with the ionospheric plasma during these active experiments. A primary advance is in observations of so-called narrowband SEE (NSEE) which exists roughly within ±1 kHz of the transmit wave frequency. NSEE investigation has opened the door for a potentially powerful tool for aeronomy investigations as well. An overview of several important new results associated with NSEE are discussed in this presentation, including observations, theory, computational modeling, as well as implications to new diagnostics of space plasma physics occurring during ionospheric interaction experiments.

Atomic and molecular gas phase spectrometry

NASA Astrophysics Data System (ADS)

Winefordner, J. D.

1985-10-01

The major goals of this research have been to develop diagnostical spectroscopic methods for measuring spatial/temporal temperatures and species of combustion flames and plasmas and to develop sensitive, selective, precise, reliable, rapid spectrometric methods of trace analysis of elements present in jet engine lubricating oils, metallurgical samples, and engine exhausts. The diagnostical approaches have been based upon the measurement of metal probes introduced into the flame or plasmas and the measurement of OH in flames. The measurement approaches have involved the use of laser-excited fluorescence, saturated absorption, polarization, and linear absorption. The spatial resolution in most studies is less than 1 cu mm and the temporal resolution is less than 10 ns with the use of pulsed lasers. Single pulse temperature and species measurements have also been carried out. Other diagnostical studies have involved the measurement of collisional redistribution of radiatively excited levels of Na and Tl in acetylene/02/Ar flames and the measurement of lifetimes and quantum efficiencies of atoms and ions in the inductively coupled plasmas, ICP. The latter studies indicate that the high electron number densities in ICPs are not efficient quenchers of excited atoms/ions. Temperatures of microwave atmospheric plasmas produced capacitatively and cool metastable N2 discharge produced by a dielectric discharge have also been measured.

ORNL diagnostic and modeling development for LAPD ICRF experiments

NASA Astrophysics Data System (ADS)

Isler, R. C.; Caughman, J. B. O.; Lau, C.; Martin, E. H.; Perkins, R. J.; Compernolle, B. Van; Vincena, S.; Tripathi, S. K. P.; Gekelman, W.

2017-10-01

PPPL, UCLA, and ORNL scientists have recently collaborated on a three week ICRF campaign at the upgraded LAPD device to study near field-plasma interactions associated with a single strap antenna driven at 2.38 MHz with 100 kW of RF power. This poster highlights ORNL involvement through implementation of the following diagnostics: an optical emission probe to measure neutral density, a retarding field energy analyzer to measure fast ions, phase locked imaging to measure line integrated RF-driven optical emission fluctuations, and an RF compensated triple Langmuir probe to measure density and temperature. To interpret the results of the experimental campaign a 3D cold plasma finite element model with realistic antenna and vacuum vessel geometry was developed in COMSOL. A summary of these results will be discussed. Highlights include a proof of principle localized and spatially resolved measurement of the neutral density, a strong increase in RF-driven optical emission fluctuations directly in front of the RF antenna strap, a shift in fast ion energies near the plasma edge, and qualitative agreement between the COMSOL cold plasma model with the various diagnostics. Funded by the DOE OFES (DE-AC05-00OR22725, DE-AC02-09CH11466, and DE-FC02-07ER54918) and the Univ. of California (12-LR-237124).

Real-time plasma control based on the ISTTOK tomography diagnostica)

NASA Astrophysics Data System (ADS)

Carvalho, P. J.; Carvalho, B. B.; Neto, A.; Coelho, R.; Fernandes, H.; Sousa, J.; Varandas, C.; Chávez-Alarcón, E.; Herrera-Velázquez, J. J. E.

2008-10-01

The presently available processing power in generic processing units (GPUs) combined with state-of-the-art programmable logic devices benefits the implementation of complex, real-time driven, data processing algorithms for plasma diagnostics. A tomographic reconstruction diagnostic has been developed for the ISTTOK tokamak, based on three linear pinhole cameras each with ten lines of sight. The plasma emissivity in a poloidal cross section is computed locally on a submillisecond time scale, using a Fourier-Bessel algorithm, allowing the use of the output signals for active plasma position control. The data acquisition and reconstruction (DAR) system is based on ATCA technology and consists of one acquisition board with integrated field programmable gate array (FPGA) capabilities and a dual-core Pentium module running real-time application interface (RTAI) Linux. In this paper, the DAR real-time firmware/software implementation is presented, based on (i) front-end digital processing in the FPGA; (ii) a device driver specially developed for the board which enables streaming data acquisition to the host GPU; and (iii) a fast reconstruction algorithm running in Linux RTAI. This system behaves as a module of the central ISTTOK control and data acquisition system (FIRESIGNAL). Preliminary results of the above experimental setup are presented and a performance benchmarking against the magnetic coil diagnostic is shown.

Modernized active spectroscopic diagnostics (CXRS) of the T-10 tokamak

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

Krupin, V. A., E-mail: Krupin-VA@nrcki.ru; Klyuchnikov, L. A., E-mail: Lklyuchnikov@list.ru; Korobov, K. V., E-mail: Korobov-KV@nrcki.ru

2015-12-15

This work presents the results of modernization of the CXRS (charge exchange recombination spectroscopy) diagnostics [1] at the T-10 tokamak. The relevance of this work is due to the importance of measurements of the ion temperature and nuclei density of the working gas and impurities for analysis of transport processes in the plasma ion component. Measurements of radial profiles of the ion temperature are extremely important for investigating the geodesic acoustic mode behavior which is conducted at the T-10 [2]. The modernized scheme of CXRS measurements, as well as the design and operational features of the spectrometer created for themore » new diagnostics, is described. Principles of data recording and further processing are considered in detail; attention is given to the problem of calibration of the whole complex of equipment. The performed changes in diagnostics allow the measurements to be taken simultaneously in three spectral intervals: in the region of the beam line H{sub α}, the CXRS line of carbon ion C{sup 5+}, and the CXRS line of one of the hydrogen-like ions: He{sup 1+}, Li{sup 2+}, N{sup 6+}, O{sup 7+} or Ne{sup 9+}. This makes it possible to measure the density profiles of two plasma impurities simultaneously, as well as the ion temperature from CXRS lines of different elements. The modernized diagnostics significantly broadens the possibilities of studying the physics of transport processes and quasi-coherent modes of plasma oscillations at the T-10.« less

Consistency between real and synthetic fast-ion measurements at ASDEX Upgrade

NASA Astrophysics Data System (ADS)

Rasmussen, J.; Nielsen, S. K.; Stejner, M.; Geiger, B.; Salewski, M.; Jacobsen, A. S.; Korsholm, S. B.; Leipold, F.; Michelsen, P. K.; Moseev, D.; Schubert, M.; Stober, J.; Tardini, G.; Wagner, D.; The ASDEX Upgrade Team

2015-07-01

Internally consistent characterization of the properties of the fast-ion distribution from multiple diagnostics is a prerequisite for obtaining a full understanding of fast-ion behavior in tokamak plasmas. Here we benchmark several absolutely-calibrated core fast-ion diagnostics at ASDEX Upgrade by comparing fast-ion measurements from collective Thomson scattering, fast-ion {{\\text{D}}α} spectroscopy, and neutron rate detectors with numerical predictions from the TRANSP/NUBEAM transport code. We also study the sensitivity of the theoretical predictions to uncertainties in the plasma kinetic profiles. We find that theory and measurements generally agree within these uncertainties for all three diagnostics during heating phases with either one or two neutral beam injection sources. This suggests that the measurements can be described by the same model assuming classical slowing down of fast ions. Since the three diagnostics in the adopted configurations probe partially overlapping regions in fast-ion velocity space, this is also consistent with good internal agreement among the measurements themselves. Hence, our results support the feasibility of combining multiple diagnostics at ASDEX Upgrade to reconstruct the fast-ion distribution function in 2D velocity space.

Development and Implementation of a New HELIOS Diagnostic using a Fast Piezoelectric Valve on the Prototype Material Plasma Exposure eXperiment

NASA Astrophysics Data System (ADS)

Ray, Holly; Biewer, Theodore; Caneses, Juan; Green, Jonathan; Lindquist, Elizabeth; McQuown, Levon; Schmitz, Oliver

2017-10-01

A new helium line-ratio spectral monitoring (HELIOS) diagnostic, using a piezoelectric valve with high duty cycles (on/off times ms), allowing for good background correction, and measured particle flowrates on the order of 1020 particles/second is being implemented on Oak Ridge National Laboratory's (ORNL) Prototype Material Plasma Exposure eXperiment (Proto-MPEX). Built in collaboration with the University of Wisconsin - Madison, the HELIOS diagnostic communicates with a Labview program for controlled bursts of helium into the vessel. The open magnetic geometry of Proto-MPEX is ideal for testing and characterizing a HELIOS diagnostic. The circular cross-section with four ports allows for cross comparison between different diagnostics: 1) Helium injection with the piezoelectric puff valve, 2) HELIOS line-of-sight high-gain observation, 3) scan-able Double Langmuir probe, and 4) HELIOS 2D imaging observation. Electron density and temperature measurements from the various techniques will be compared. This work was supported by the US. D.O.E. contract DE-AC05-00OR22725 and DE-SC00013911.

The neutron imaging diagnostic at NIF (invited).

PubMed

Merrill, F E; Bower, D; Buckles, R; Clark, D D; Danly, C R; Drury, O B; Dzenitis, J M; Fatherley, V E; Fittinghoff, D N; Gallegos, R; Grim, G P; Guler, N; Loomis, E N; Lutz, S; Malone, R M; Martinson, D D; Mares, D; Morley, D J; Morgan, G L; Oertel, J A; Tregillis, I L; Volegov, P L; Weiss, P B; Wilde, C H; Wilson, D C

2012-10-01

A neutron imaging diagnostic has recently been commissioned at the National Ignition Facility (NIF). This new system is an important diagnostic tool for inertial fusion studies at the NIF for measuring the size and shape of the burning DT plasma during the ignition stage of Inertial Confinement Fusion (ICF) implosions. The imaging technique utilizes a pinhole neutron aperture, placed between the neutron source and a neutron detector. The detection system measures the two dimensional distribution of neutrons passing through the pinhole. This diagnostic has been designed to collect two images at two times. The long flight path for this diagnostic, 28 m, results in a chromatic separation of the neutrons, allowing the independently timed images to measure the source distribution for two neutron energies. Typically the first image measures the distribution of the 14 MeV neutrons and the second image of the 6-12 MeV neutrons. The combination of these two images has provided data on the size and shape of the burning plasma within the compressed capsule, as well as a measure of the quantity and spatial distribution of the cold fuel surrounding this core.

A high-speed two-frame, 1-2 ns gated X-ray CMOS imager used as a hohlraum diagnostic on the National Ignition Facility (invited).

PubMed

Chen, Hui; Palmer, N; Dayton, M; Carpenter, A; Schneider, M B; Bell, P M; Bradley, D K; Claus, L D; Fang, L; Hilsabeck, T; Hohenberger, M; Jones, O S; Kilkenny, J D; Kimmel, M W; Robertson, G; Rochau, G; Sanchez, M O; Stahoviak, J W; Trotter, D C; Porter, J L

2016-11-01

A novel x-ray imager, which takes time-resolved gated images along a single line-of-sight, has been successfully implemented at the National Ignition Facility (NIF). This Gated Laser Entrance Hole diagnostic, G-LEH, incorporates a high-speed multi-frame CMOS x-ray imager developed by Sandia National Laboratories to upgrade the existing Static X-ray Imager diagnostic at NIF. The new diagnostic is capable of capturing two laser-entrance-hole images per shot on its 1024 × 448 pixels photo-detector array, with integration times as short as 1.6 ns per frame. Since its implementation on NIF, the G-LEH diagnostic has successfully acquired images from various experimental campaigns, providing critical new information for understanding the hohlraum performance in inertial confinement fusion (ICF) experiments, such as the size of the laser entrance hole vs. time, the growth of the laser-heated gold plasma bubble, the change in brightness of inner beam spots due to time-varying cross beam energy transfer, and plasma instability growth near the hohlraum wall.

HIV-1 tropism testing in subjects achieving undetectable HIV-1 RNA: diagnostic accuracy, viral evolution and compartmentalization.

PubMed

Pou, Christian; Codoñer, Francisco M; Thielen, Alexander; Bellido, Rocío; Pérez-Álvarez, Susana; Cabrera, Cecilia; Dalmau, Judith; Curriu, Marta; Lie, Yolanda; Noguera-Julian, Marc; Puig, Jordi; Martínez-Picado, Javier; Blanco, Julià; Coakley, Eoin; Däumer, Martin; Clotet, Bonaventura; Paredes, Roger

2013-01-01

Technically, HIV-1 tropism can be evaluated in plasma or peripheral blood mononuclear cells (PBMCs). However, only tropism testing of plasma HIV-1 has been validated as a tool to predict virological response to CCR5 antagonists in clinical trials. The preferable tropism testing strategy in subjects with undetectable HIV-1 viremia, in whom plasma tropism testing is not feasible, remains uncertain. We designed a proof-of-concept study including 30 chronically HIV-1-infected individuals who achieved HIV-1 RNA <50 copies/mL during at least 2 years after first-line ART initiation. First, we determined the diagnostic accuracy of 454 and population sequencing of gp120 V3-loops in plasma and PBMCs, as well as of MT-2 assays before ART initiation. The Enhanced Sensitivity Trofile Assay (ESTA) was used as the technical reference standard. 454 sequencing of plasma viruses provided the highest agreement with ESTA. The accuracy of 454 sequencing decreased in PBMCs due to reduced specificity. Population sequencing in plasma and PBMCs was slightly less accurate than plasma 454 sequencing, being less sensitive but more specific. MT-2 assays had low sensitivity but 100% specificity. Then, we used optimized 454 sequence data to investigate viral evolution in PBMCs during viremia suppression and only found evolution of R5 viruses in one subject. No de novo CXCR4-using HIV-1 production was observed over time. Finally, Slatkin-Maddison tests suggested that plasma and cell-associated V3 forms were sometimes compartmentalized. The absence of tropism shifts during viremia suppression suggests that, when available, testing of stored plasma samples is generally safe and informative, provided that HIV-1 suppression is maintained. Tropism testing in PBMCs may not necessarily produce equivalent biological results to plasma, because the structure of viral populations and the diagnostic performance of tropism assays may sometimes vary between compartments. Thereby, proviral DNA tropism testing should be specifically validated in clinical trials before it can be applied to routine clinical decision-making.

Diagnostic for Plasma Enhanced Chemical Vapor Deposition and Etch Systems

NASA Technical Reports Server (NTRS)

Cappelli, Mark A.

1999-01-01

In order to meet NASA's requirements for the rapid development and validation of future generation electronic devices as well as associated materials and processes, enabling technologies ion the processing of semiconductor materials arising from understanding etch chemistries are being developed through a research collaboration between Stanford University and NASA-Ames Research Center, Although a great deal of laboratory-scale research has been performed on many of materials processing plasmas, little is known about the gas-phase and surface chemical reactions that are critical in many etch and deposition processes, and how these reactions are influenced by the variation in operating conditions. In addition, many plasma-based processes suffer from stability and reliability problems leading to a compromise in performance and a potentially increased cost for the semiconductor manufacturing industry. Such a lack of understanding has hindered the development of process models that can aid in the scaling and improvement of plasma etch and deposition systems. The research described involves the study of plasmas used in semiconductor processes. An inductively coupled plasma (ICP) source in place of the standard upper electrode assembly of the Gaseous Electronics Conference (GEC) radio-frequency (RF) Reference Cell is used to investigate the discharge characteristics and chemistries. This ICP source generates plasmas with higher electron densities (approximately 10(exp 12)/cu cm) and lower operating pressures (approximately 7 mTorr) than obtainable with the original parallel-plate version of the GEC Cell. This expanded operating regime is more relevant to new generations of industrial plasma systems being used by the microelectronics industry. The motivation for this study is to develop an understanding of the physical phenomena involved in plasma processing and to measure much needed fundamental parameters, such as gas-phase and surface reaction rates. species concentration, temperature, ion energy distribution, and electron number density. A wide variety of diagnostic techniques are under development through this consortium grant to measure these parameters. including molecular beam mass spectrometry (MBMS). Fourier transform infrared (FTIR) spectroscopy, broadband ultraviolet (UV) absorption spectroscopy, a compensated Langmuir probe. Additional diagnostics. Such as microwave interferometry and microwave absorption for measurements of plasma density and radical concentrations are also planned.

Measurement of Two-Plasmon-Decay Dependence on Plasma Density Scale Length

NASA Astrophysics Data System (ADS)

Haberberger, D.

2013-10-01

An accurate understanding of the plasma scale-length (Lq) conditions near quarter-critical density is important in quantifying the hot electrons generated by the two-plasmon-decay (TPD) instability in long-scale-length plasmas. A novel target platform was developed to vary the density scale length and an innovative diagnostic was implemented to measure the density profiles above 1021 cm-3 where TPD is expected to have the largest growth. A series of experiments was performed using the four UV (351-nm) beams on OMEGA EP that varied the Lq by changing the radius of curvature of the target while maintaining a constant Iq/Tq. The fraction of laser energy converted to hot electrons (fhot) was observed to increase rapidly from 0.005% to 1% by increasing the plasma scale length from 130 μm to 300 μm, corresponding to target diameters of 0.4 mm to 8 mm. A new diagnostic was developed based on refractometry using angular spectral filters to overcome the large phase accumulation in standard interferometric techniques. The angular filter refractometer measures the refraction angles of a 10-ps, 263-nm probe laser after propagating through the plasma. An angular spectral filter is used in the Fourier plane of the probe beam, where the refractive angles of the rays are mapped to space. The edges of the filter are present in the image plane and represent contours of constant refraction angle. These contours are used to infer the phase of the probe beam, which are used to calculate the plasma density profile. In long-scale-length plasmas, the diagnostic currently measures plasma densities from ~1019 cm-3 to ~2 × 1021 cm-3. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944. In collaboration with D. H. Edgell, S. X. Hu, S. Ivancic, R. Boni, C. Dorrer, and D. H. Froula (Laboratory for Laser Energetics, U. of Rochester).

Low Temperature Atmospheric Argon Plasma: Diagnostics and Medical Applications

NASA Astrophysics Data System (ADS)

Ermolaeva, Svetlana; Petrov, Oleg; Zigangirova, Nailya; Vasiliev, Mikhail; Sysolyatina, Elena; Antipov, Sergei; Alyapyshev, Maxim; Kolkova, Natalia; Mukhachev, Andrei; Naroditsky, Boris; Shimizu, Tetsuji; Grigoriev, Anatoly; Morfill, Gregor; Fortov, Vladimir; Gintsburg, Alexander

This study was devoted to diagnostic of low temperature plasma produced by microwave generator and investigation of its bactericidal effect against bacteria in biofilms and within eukaryotic cells. The profile of gas temperature near the torch outlet was measured. The spectrum in a wide range of wavelengths was derived by the method of optical emission spec-troscopy. Probe measurements of the floating potential of plasma were car-ried out. The estimation and adaptation of parameters of plasma flow (tem-perature, velocity, ion number density) according to medico-technical requirements were produced. The model of immersed surface-associated biofilms formed by Gram-negative bacteria, Pseudomonas aeruginosa and Burkholderia cenocepacia, and Gram-positive bacteria, Staphylococcus aureus, was used to assess bactericidal effects of plasma treatment. Reduction in the concentration of live bacteria in biofilms treated with plasma for 5 min was demonstrated by measuring Live/Dead fluorescent labeling and using direct plating. The intracellular infection model with the pathogenic bacterium, Chlamydia trachomatis, was used to study the efficacy of microwave argon plasma against intracellular parasites. A 2 min plasma treatment of mouse cells infected with C. trachomatis reduced infectious bacteria by a factor of 2×106. Plasma treatment diminished the number of viable host cells by about 20%. When the samples were covered with MgF2 glass to obstruct active particles and UV alone was applied, the bactericidal effect was re-duced by 5×104 fold compared to the whole plasma.

[Evaluation of NMR relaxation method as a diagnostic tool for donor blood analysis and patients with hematologic diseases and burns].

PubMed

Gangardt, M G; Popova, O V; Shmarov, D A; Kariakina, N F; Papish, E A; Kozinets, G I

2002-08-01

Diagnostic value of the NMR-relaxation method in the blood plasma was estimated in the patients with different pathologies. The time of hydrogen nuclei longitudinal relaxation (T1) in the health donors of the blood, in the patients with oncopathology (hemoblastoses) and in the cases with anemia and burning disease were investigated. The time of the longitudinal relaxation (T1) was measured by automated NMR-relaxometer "Palma" (Russia). The working frequency was equal to 35 MHz, the temperature was 45 +/- 0.1 degrees C. For the single measurement 0.2 ml of blood obtained from heparinized venous blood 1.5 hours after its taking was used. The time of the longitudinal relaxation (T1) was shown to be 1.78 +/- 0.02 in the health donors, 1.70 +/- 0.06 s in cases with anemia, 1.97 +/- 0.48 c in patients with leucosis, 2.40 +/- 0.12 s in patients with burns. The sensitivity and the specificity of diagnostics of leucosis based upon the results of the only single T1 measurement in blood plasma were concluded to be 75%. It proves the significant T1 change both in patients with anemia and burning disease of the II-III degree. However it is evidently insufficient for selective use of NMR-relaxation blood plasma (serum) in the diagnostics of anemia and leucosis. The data obtained prove also the possibility of use of NMR-relaxation blood plasma (serum) for control of the hemostasis state during treatment or remission.

Nonperturbative measurement of the local magnetic field using pulsed polarimetry for fusion reactor conditions (invited).

PubMed

Smith, Roger J

2008-10-01

A novel diagnostic technique for the remote and nonperturbative sensing of the local magnetic field in reactor relevant plasmas is presented. Pulsed polarimetry [Patent No. 12/150,169 (pending)] combines optical scattering with the Faraday effect. The polarimetric light detection and ranging (LIDAR)-like diagnostic has the potential to be a local B(pol) diagnostic on ITER and can achieve spatial resolutions of millimeters on high energy density (HED) plasmas using existing lasers. The pulsed polarimetry method is based on nonlocal measurements and subtle effects are introduced that are not present in either cw polarimetry or Thomson scattering LIDAR. Important features include the capability of simultaneously measuring local T(e), n(e), and B(parallel) along the line of sight, a resiliency to refractive effects, a short measurement duration providing near instantaneous data in time, and location for real-time feedback and control of magnetohydrodynamic (MHD) instabilities and the realization of a widely applicable internal magnetic field diagnostic for the magnetic fusion energy program. The technique improves for higher n(e)B(parallel) product and higher n(e) and is well suited for diagnosing the transient plasmas in the HED program. Larger devices such as ITER and DEMO are also better suited to the technique, allowing longer pulse lengths and thereby relaxing key technology constraints making pulsed polarimetry a valuable asset for next step devices. The pulsed polarimetry technique is clarified by way of illustration on the ITER tokamak and plasmas within the magnetized target fusion program within present technological means.

Serial data acquisition for the X-ray plasma diagnostics with selected GEM detector structures

NASA Astrophysics Data System (ADS)

Czarski, T.; Chernyshova, M.; Pozniak, K. T.; Kasprowicz, G.; Zabolotny, W.; Kolasinski, P.; Krawczyk, R.; Wojenski, A.; Zienkiewicz, P.

2015-10-01

The measurement system based on GEM—Gas Electron Multiplier detector is developed for X-ray diagnostics of magnetic confinement tokamak plasmas. The paper is focused on the measurement subject and describes the fundamental data processing to obtain reliable characteristics (histograms) useful for physicists. The required data processing have two steps: 1—processing in the time domain, i.e. events selections for bunches of coinciding clusters, 2—processing in the planar space domain, i.e. cluster identification for the given detector structure. So, it is the software part of the project between the electronic hardware and physics applications. The whole project is original and it was developed by the paper authors. The previous version based on 1-D GEM detector was applied for the high-resolution X-ray crystal spectrometer KX1 in the JET tokamak. The current version considers 2-D detector structures for the new data acquisition system. The fast and accurate mode of data acquisition implemented in the hardware in real time can be applied for the dynamic plasma diagnostics. Several detector structures with single-pixel sensors and multi-pixel (directional) sensors are considered for two-dimensional X-ray imaging. Final data processing is presented by histograms for selected range of position, time interval and cluster charge values. Exemplary radiation source properties are measured by the basic cumulative characteristics: the cluster position distribution and cluster charge value distribution corresponding to the energy spectra. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

Preanalytical blood sample workup for cell-free DNA analysis using Droplet Digital PCR for future molecular cancer diagnostics.

PubMed

van Ginkel, Joost H; van den Broek, Daan A; van Kuik, Joyce; Linders, Dorothé; de Weger, Roel; Willems, Stefan M; Huibers, Manon M H

2017-10-01

In current molecular cancer diagnostics, using blood samples of cancer patients for the detection of genetic alterations in plasma (cell-free) circulating tumor DNA (ctDNA) is an emerging practice. Since ctDNA levels in blood are low, highly sensitive Droplet Digital PCR (ddPCR) can be used for detecting rare mutational targets. In order to perform ddPCR on blood samples, a standardized procedure for processing and analyzing blood samples is necessary to facilitate implementation into clinical practice. Therefore, we assessed the technical sample workup procedure for ddPCR on blood plasma samples. Blood samples from healthy individuals, as well as lung cancer patients were analyzed. We compared different methods and protocols for sample collection, storage, centrifugation, isolation, and quantification. Cell-free DNA (cfDNA) concentrations of several wild-type targets and BRAF and EGFR-mutant ctDNA concentrations quantified by ddPCR were primary outcome measurements. Highest cfDNA concentrations were measured in blood collected in serum tubes. No significant differences in cfDNA concentrations were detected between various time points of up to 24 h until centrifugation. Highest cfDNA concentrations were detected after DNA isolation with the Quick cfDNA Serum & Plasma Kit, while plasma isolation using the QIAamp Circulating Nucleic Acid Kit yielded the most consistent results. DdPCR results on cfDNA are highly dependent on multiple factors during preanalytical sample workup, which need to be addressed during the development of this diagnostic tool for cancer diagnostics in the future. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Solar Prominence Modelling and Plasma Diagnostics at ALMA Wavelengths

NASA Astrophysics Data System (ADS)

Rodger, Andrew; Labrosse, Nicolas

2017-09-01

Our aim is to test potential solar prominence plasma diagnostics as obtained with the new solar capability of the Atacama Large Millimeter/submillimeter Array (ALMA). We investigate the thermal and plasma diagnostic potential of ALMA for solar prominences through the computation of brightness temperatures at ALMA wavelengths. The brightness temperature, for a chosen line of sight, is calculated using the densities of electrons, hydrogen, and helium obtained from a radiative transfer code under non-local thermodynamic equilibrium (non-LTE) conditions, as well as the input internal parameters of the prominence model in consideration. Two distinct sets of prominence models were used: isothermal-isobaric fine-structure threads, and large-scale structures with radially increasing temperature distributions representing the prominence-to-corona transition region. We compute brightness temperatures over the range of wavelengths in which ALMA is capable of observing (0.32 - 9.6 mm), however, we particularly focus on the bands available to solar observers in ALMA cycles 4 and 5, namely 2.6 - 3.6 mm (Band 3) and 1.1 - 1.4 mm (Band 6). We show how the computed brightness temperatures and optical thicknesses in our models vary with the plasma parameters (temperature and pressure) and the wavelength of observation. We then study how ALMA observables such as the ratio of brightness temperatures at two frequencies can be used to estimate the optical thickness and the emission measure for isothermal and non-isothermal prominences. From this study we conclude that for both sets of models, ALMA presents a strong thermal diagnostic capability, provided that the interpretation of observations is supported by the use of non-LTE simulation results.

Development of a Technique for Measuring Local Electric Field Fluctuations in High Temperature Plasmas

NASA Astrophysics Data System (ADS)

Burke, M. G.; Bakken, M. R.; Fonck, R. J.; Lewicki, B. T.; Rhodes, A. T.; Winz, G. R.

2016-10-01

A novel diagnostic for measuring local electric field fluctuations in high temperature plasmas is being developed. It employs high-speed measurements of the spectral separation and/or line intensities of the motional Stark effect (MSE) Hα multiplet emitted from a low divergence, 80 keV diagnostic neutral beam. A spatial heterodyne spectrometer (SHS) coupled to a 500 kHz CMOS camera provides the high resolution ( 0.025 nm) and throughput (<=0.1 cm2str) required for the measurement. The Fizeau fringe pattern produced by the SHS provides the Fourier transform of the input spectrum. Line broadening due to the large collection lens at the tokamak can be compensated by phase correcting the resulting fringe pattern. Based on simple tokamak turbulence scalings, Ẽ /EMSE 10-3 is expected for the core plasma in present experiments. To observe these low fluctuation levels, cross-correlation between adjacent spatial points and/or simultaneously measured ñ will be employed to suppress photon noise that is comparable to the turbulent signal. The SHS Littrow wavenumber and grating constant can be chosen to reduce the number of detectors needed to resolve changes in the input spectrum. This allows multi-spatial point measurements using 4-6 discrete photodiodes each, with no loss in sensitivity to Ẽ /EMSE . To validate this diagnostic concept, the diagnostic neutral beam will be fired into a magnetized target plasma (B <=0.5 T) comparable to a tokamak edge, with Ẽ applied parallel or perpendicular to EMSE via biased electrodes. Work supported by US DOE Grant DE-FG02-89ER53296.

Measurement of type-I edge localized mode pulse propagation in scrape-off layer using optical system of motional Stark effect diagnostics in JT-60U

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

Suzuki, T.; Oyama, N.; Asakura, N.

2010-04-15

Propagation of plasma ejected by type-I edge localized mode (ELM) has been measured in scrape-off layer (SOL) of the JT-60U tokamak, using optical system of motional Stark effect (MSE) diagnostics as beam emission spectroscopy (BES) diagnostics through a new technique developed. This MSE/BES system measures D{alpha} emission from heating neutral beam excited by collisions with the ejected plasma, as well as background light (e.g., bremsstrahlung). While spatio-temporal change in the beam emission gives information on propagation of the ejected plasma, the background light that is observed simultaneously in all spatial channels veils the information. In order to separate the beammore » emission and the background light, a two-wavelength detector is newly introduced into the MSE/BES system. The detector observes simultaneously at the same spatial point in two distinct wavelengths using two photomultiplier tubes through two interference filters. One of the filters is adjusted to the central wavelength of the beam emission for the MSE diagnostics, and the other is outside the beam emission spectrum. Eliminating the background light, temporal change in the net beam emission in the SOL has been evaluated. Comparing conditionally averaged beam emission with respect to 594 ELMs in a discharge at five spatial channels (0.02-0.3 m outside the main plasma near equatorial plane), radial velocity of the ELM pulse propagation in SOL is evaluated to be 0.8-1.8 km/s ({approx}1.4 km/s for least-mean-squared fitting).« less

Gaseous electron multiplier-based soft x-ray plasma diagnostics development: Preliminary tests at ASDEX Upgrade.

PubMed

Chernyshova, M; Malinowski, K; Czarski, T; Wojeński, A; Vezinet, D; Poźniak, K T; Kasprowicz, G; Mazon, D; Jardin, A; Herrmann, A; Kowalska-Strzęciwilk, E; Krawczyk, R; Kolasiński, P; Zabołotny, W; Zienkiewicz, P

2016-11-01

A Gaseous Electron Multiplier (GEM)-based detector is being developed for soft X-ray diagnostics on tokamaks. Its main goal is to facilitate transport studies of impurities like tungsten. Such studies are very relevant to ITER, where the excessive accumulation of impurities in the plasma core should be avoided. This contribution provides details of the preliminary tests at ASDEX Upgrade (AUG) with a focus on the most important aspects for detector operation in harsh radiation environment. It was shown that both spatially and spectrally resolved data could be collected, in a reasonable agreement with other AUG diagnostics. Contributions to the GEM signal include also hard X-rays, gammas, and neutrons. First simulations of the effect of high-energy photons have helped understanding these contributions.

Gaseous electron multiplier-based soft x-ray plasma diagnostics development: Preliminary tests at ASDEX Upgrade

NASA Astrophysics Data System (ADS)

Chernyshova, M.; Malinowski, K.; Czarski, T.; Wojeński, A.; Vezinet, D.; Poźniak, K. T.; Kasprowicz, G.; Mazon, D.; Jardin, A.; Herrmann, A.; Kowalska-Strzeciwilk, E.; Krawczyk, R.; Kolasiński, P.; Zabołotny, W.; Zienkiewicz, P.

2016-11-01

A Gaseous Electron Multiplier (GEM)-based detector is being developed for soft X-ray diagnostics on tokamaks. Its main goal is to facilitate transport studies of impurities like tungsten. Such studies are very relevant to ITER, where the excessive accumulation of impurities in the plasma core should be avoided. This contribution provides details of the preliminary tests at ASDEX Upgrade (AUG) with a focus on the most important aspects for detector operation in harsh radiation environment. It was shown that both spatially and spectrally resolved data could be collected, in a reasonable agreement with other AUG diagnostics. Contributions to the GEM signal include also hard X-rays, gammas, and neutrons. First simulations of the effect of high-energy photons have helped understanding these contributions.

Stray light analysis for the Thomson scattering diagnostic of the ETE Tokamak

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

Berni, L. A.; Albuquerque, B. F. C.

2010-12-15

Thomson scattering is a well-established diagnostic for measuring local electron temperature and density in fusion plasma, but this technique is particularly difficult to implement due to stray light that can easily mask the scattered signal from plasma. To mitigate this problem in the multipoint Thomson scattering system implemented at the ETE (Experimento Tokamak Esferico) a detailed stray light analysis was performed. The diagnostic system was simulated in ZEMAX software and scattering profiles of the mechanical parts were measured in the laboratory in order to have near realistic results. From simulation, it was possible to identify the main points that contributemore » to the stray signals and changes in the dump were implemented reducing the stray light signals up to 60 times.« less

The LeRC rail accelerators: Test designs and diagnostic techniques

NASA Technical Reports Server (NTRS)

Zana, L. M.; Kerslake, W. R.; Sturman, J. C.; Wang, S. Y.; Terdan, F. F.

1983-01-01

The feasibility of using rail accelerators for various in-space and to-space propulsion applications was investigated. A 1 meter, 24 sq mm bore accelerator was designed with the goal of demonstrating projectile velocities of 15 km/sec using a peak current of 200 kA. A second rail accelerator, 1 meter long with a 156.25 sq mm bore, was designed with clear polycarbonate sidewalls to permit visual observation of the plasma arc. A study of available diagnostic techniques and their application to the rail accelerator is presented. Specific topics of discussion include the use of interferometry and spectroscopy to examine the plasma armature as well as the use of optical sensors to measure rail displacement during acceleration. Standard diagnostics such as current and voltage measurements are also discussed.

Ponderomotive perturbations of low density low-temperature plasma under laser Thomson scattering diagnostics

NASA Astrophysics Data System (ADS)

Shneider, Mikhail N.

2017-10-01

The ponderomotive perturbation in the interaction region of laser radiation with a low density and low-temperature plasma is considered. Estimates of the perturbation magnitude are determined from the plasma parameters, geometry, intensity, and wavelength of laser radiation. It is shown that ponderomotive perturbations can lead to large errors in the electron density when measured using Thomson scattering.

Study of the Role of Vortex Annihilation in the Mechanism of Neutron and X-Ray Production in the Plasma Focus.

DTIC Science & Technology

This paper shows that an understanding of the nature of the x-ray and neutron producing processes in the plasma focus requires a study of the ’fine...structure’ of the plasma focus and that this fine structure study requires diagnostic techniques with spacial resolution down to 50 micrometers and

An investigation into the role of metastable states on excited populations of weakly ionized argon plasmas, with applications for optical diagnostics

NASA Astrophysics Data System (ADS)

Arnold, Nicholas; Loch, Stuart; Ballance, Connor; Thomas, Ed

2017-10-01

Low temperature plasmas (Te < 10 eV) are ubiquitous in the medical, industrial, basic, and dusty plasma communities, and offer an opportunity for researchers to gain a better understanding of atomic processes in plasmas. Here, we report on a new atomic dataset for neutral and low charge states of argon, from which rate coefficients and cross-sections for the electron-impact excitation of neutral argon are determined. We benchmark by comparing with electron impact excitation cross-sections available in the literature, with very good agreement. We have used the Atomic Data and Analysis Structure (ADAS) code suite to calculate a level-resolved, generalized collisional-radiative (GCR) model for line emission in low temperature argon plasmas. By combining our theoretical model with experimental electron temperature, density, and spectral measurements from the Auburn Linear eXperiment for Instability Studies (ALEXIS), we have developed diagnostic techniques to measure metastable fraction, electron temperature, and electron density. In the future we hope to refine our methods, and extend our model to plasmas other than ALEXIS. Supported by the U.S. Department of Energy. Grant Number: DE-FG02-00ER54476.

Phenomenology of beam driven modes in the field reversed configuration

NASA Astrophysics Data System (ADS)

Magee, Richard; Bolte, Nathan; Clary, Ryan; Necas, Ales; Korepanov, Sergey; Smirnov, Artem; Thompson, Matthew; Tajima, Toshiki; THE TAE Team

2016-10-01

The C-2U experiment offers a unique plasma environment combining a high beta field reversed configuration (FRC) embedded in a low beta magnetic mirror with high power neutral beam injection. The beams are injected tangentially into a modest magnetic field so that the orbits of the resulting fast ions encircle the entire plasma. These large orbit particles sustain and stabilize the plasma and suppress turbulence. Measurements of magnetic fluctuations at the edge of the plasma reveal the presence of three coherent beam driven modes: a low frequency, chirping mode, a mode near the ion cyclotron frequency, and a high frequency compressional Alfven mode. Remarkably, none of these modes are observed to have a deleterious effect on global plasma confinement. In fact, the cyclotron mode has the beneficial effect of dramatically enhancing the DD fusion reaction rate by drawing a trail from the plasma ion energy distribution on a sub-collisional timescale. In this presentation, we experimentally characterize the beam driven modes in the C-2U FRC with data from multiple diagnostics including magnetics, spectroscopy, neutral particle analyzers and fusion product diagnostics. Results are compared to a particle-in-cell simulation in a simplified geometry.

Nanoparticle forming reactive plasmas: a multidiagnostic approach

NASA Astrophysics Data System (ADS)

Hinz, Alexander; Wahl, Erik von; Faupel, Franz; Strunskus, Thomas; Kersten, Holger

2018-05-01

With an ever increasing interest in functional materials based on nanoparticles a large amount of research in this field is dedicated to the development of new production methods for nanoparticles. A promising class of methods for the production of nanoparticles is reactive plasmas. However, since the particle formation process and the interaction between the particles and the plasma are so far not completely understood, it remains difficult to control the particle formation. As the interaction between the nanoparticles and the plasma in which they are dispersed is complex the use of one or two diagnostics often provides only an incomplete understanding of the involved processes. Thus a multidiagnostic approach is needed. This contribution reviews the latest results from the study of nanoparticle formation in a hydrocarbon-based reactive plasma by such a multidiagnostic approach. It is shown that the use of various diagnostics like an IV-probe, optical emission spectroscopy, and a multipole resonance probe in conjunction with an investigation of the particle formation provides a much more detailed picture of these interesting, yet challenging, systems. Contribution to the Topical Issue "Fundamentals of Complex Plasmas", edited by Jürgen Meichsner, Michael Bonitz, Holger Fehske, Alexander Piel.

The radio-frequency fluctuation effect on the floating harmonic method

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

Lee, Jaewon; Kim, Kyung-Hyun; Kim, Dong-Hwan

2016-08-15

The radio-frequency (RF) plasma diagnostics with an electrical probe facing a challenge, because the RF fluctuation oscillates the plasma potential and distorts the current-voltage (I-V) curve. As Langmuir probe is widely used in plasma diagnostics, many researchers have been studying the effect of RF fluctuation on probe and compensation methods. On the other hand, there have not been enough studies on the fluctuation effect on the floating harmonic method. Therefore, we investigated the impact of RF fluctuation on the floating harmonic method theoretically and experimentally. When the electrons are in ideal Maxwellian distribution, the floating potential is negatively shifted bymore » the RF fluctuation, but the fluctuation does not distort I-V curve around the floating potential. However, in practical plasmas, the I-V curve and their harmonic components are distorted. This RF fluctuation effect becomes more significant in a low density plasma with a high impedance sheath. The second harmonic current decreases with the RF fluctuation while the first harmonic current is merely affected. Therefore, the electron temperatures measured with the floating harmonic method under low density plasma with uncompensated probe are overestimated than the results obtained with the compensated probe.« less

Foundations of a laser-accelerated plasma diagnostics and beam stabilization with miniaturized Rogowski coils

NASA Astrophysics Data System (ADS)

Gruenwald, J.; Kocoń, D.; Khikhlukha, D.

2018-03-01

In order to introduce spatially resolved measurements of the plasma density in a plasma accelerated by a laser, a novel concept is proposed in this work. We suggest the usage of an array of miniaturized Rogowski coils to measure the current contributions parallel to the laser beam with a spatial resolution in the sub-mm range. The principle of the experimental setup will be shown in 3-D CAD models. The coils are coaxial to the plasma channel (e.g. a hydrogen filled capillary, which is frequently used in laser-plasma acceleration experiments). This plasma diagnostics method is simple, robust and it is a passive measurement technique, which does not disturb the plasma itself. As such coils rely on a Biot-Savart inductivity, they allow to separate the contributions of the parallel from perpendicular currents (with respect to the laser beam). Rogowski coils do not have a ferromagnetic core. Hence, non-linear effects resulting from such a core are to be neglected, which increases the reliability of the obtained data. They also allow the diagnosis of transient signals that carry high currents (up to several hundred kA) on very short timescales. Within this paper some predictions about the time resolution of such coils will be presented along with simple theoretical considerations.

D-Dimer and prothrombin fragment 1 + 2 in urine and plasma in patients with clinically suspected venous thromboembolism.

PubMed

Wexels, Fredrik; Seljeflot, Ingebjørg; Pripp, Are H; Dahl, Ola E

2016-06-01

Increased levels of urine prothrombin fragment 1 + 2 was recently reported to be associated with imaging-verified venous thromboembolism. In this study we evaluated the relationship between plasma D-dimer and plasma and urine prothrombin fragment 1 + 2 in patients with suspected venous thromboembolism. Urine and blood samples were collected from patients with suspected pulmonary embolism or deep vein thrombosis. The samples were analysed with commercially available ELISA kits. The diagnosis of venous thromboembolism was verified with contrast-enhanced computer tomography of the pulmonary arteries or lower extremity deep vein compression ultrasound and venography as appropriate. Venous thromboembolism was diagnosed in 150 of 720 patients. Significantly higher levels of plasma D-dimer and prothrombin fragment 1 + 2 in plasma and urine were found in those with imaging-confirmed venous thromboembolism versus those without (P < 0.001). The correlation between the three biomarkers was statistically significant (range of rs values 0.45-0.65, P < 0.001). Plasma D-dimer had the highest diagnostic accuracy followed by prothrombin fragment 1 + 2 in plasma. Further development of ELISA analyses for urine testing of prothrombin fragment 1 + 2 may improve its diagnostic accuracy.

Plasma free metanephrines are superior to urine and plasma catecholamines and urine catecholamine metabolites for the investigation of phaeochromocytoma.

PubMed

Hickman, Peter E; Leong, Michelle; Chang, Julia; Wilson, Susan R; McWhinney, Brett

2009-02-01

To compare the relative diagnostic efficacy of several different tests used to establish a diagnosis of phaeochromocytoma, in patients with a proven diagnosis of phaeochromocytoma, and in hospital patients with significant disease of other types. We prospectively compared biochemical markers of catecholamine output and metabolism in plasma and urine in 22 patients with histologically proven phaeochromocytoma, 15 intensive care unit (ICU) patients, 30 patients on chronic haemodialysis and both hypertensive (n = 10) and normotensive (n = 16) controls. Receiver operating characteristic curves were plotted. At the point of maximum efficiency, plasma free metanephrines showed 100% sensitivity and 97.6% specificity, compared with plasma catecholamines (78.6% and 70.7%), urine catecholamines (78.6% and 87.8%), urine metanephrines (85.7% and 95.1%), and urine hydroxymethoxymandelic acid (HMMA or VMA) (93.0% and 75.8%). All patients with phaeochromocytoma had plasma free metanephrine concentrations at least 27% above the upper limit of the reference range. Only three other patients (two on haemodialysis and one in ICU) had PFM concentrations more than 50% above the upper limit of the reference range. In patients with phaeochromocytoma, plasma free metanephrines displayed superior diagnostic sensitivity and specificity compared with other biochemical markers of catecholamine output and metabolism.

Capillary whole blood testing by a new portable monitor. Comparison with standard determination of the international normalized ratio.

PubMed

de Miguel, Dunia; Burgaleta, Carmen; Reyes, Eduardo; Pascual, Teresa

2003-07-01

We evaluated a new portable monitor (AvoSure PT PRO, Menarini Diagnostics, Firenze, Italy) developed to test the prothrombin time in capillary blood and plasma by comparing it with the standard laboratory determination. We studied 62 patients receiving acenocoumarol therapy. The international normalized ratio (INR) in capillary blood was analyzed by 2 methods: AvoSure PT PRO and Thrombotrack Nycomed Analyzer (Axis-Shield, Dundee, Scotland). Parallel studies were performed in plasma samples by a reference method using the Behring Coagulation Timer (Behring Diagnostics, Marburg, Germany). Plasma samples also were tested with the AvoSure PT PRO. Correlation was good for INR values for capillary blood and plasma samples by AvoSure PT PRO and our reference method (R2 = 0.8596) and for capillary blood samples tested by the AvoSure PT PRO and Thrombotrack Nycomed Analyzer (R2 = 0.8875). The correlation for INR in capillary blood and plasma samples by AvoSure PT PRO was 0.6939 (P < .0004). Capillary blood determinations are rapid and effective for monitoring oral anticoagulation therapy and have a high correlation to plasma determinations. AvoSure PT PRO is accurate for controlling INR in plasma and capillary blood samples, may be used in outpatient clinics, and has advantages over previous portable monitors.

Measurements by the plasma diagnostics package on STS-3

NASA Technical Reports Server (NTRS)

Shawhan, S. D.; Murphy, G. B.

1982-01-01

A comprehensive set of measurements about the orbiter environment are provided by the plasma diagnostics package (PDP). Ion and electron particle densities, energies, and spatial distribution functions; ion mass for identification of particular molecular ion species; and magnetic fields, electric fields and electromagnetic waves over a broad frequency range are studied. Shuttle environmental measurements will be made both on the pallet and, by use of the remote manipulator system (RMS), the PDP will be maneuvered in and external to the bay area to continue environmental measurements and to carry on a joint plasma experiment with the Utah State University fast-pulsed electron generator. Results of orbiter environment EMI measurements and S-band field strengths as well as preliminary results from wake search operations indicating wake boundary identifiers are reported.

Thomson scattering diagnostics of steady state and pulsed welding processes without and with metal vapor

NASA Astrophysics Data System (ADS)

Kühn-Kauffeldt, M.; Marqués, J.-L.; Schein, J.

2015-01-01

Thomson scattering is applied to measure temperature and density of electrons in the arc plasma of the direct current gas tungsten arc welding (GTAW) process and pulsed gas metal arc welding (GMAW) process. This diagnostic technique allows to determine these plasma parameters independent from the gas composition and heavy particles temperature. The experimental setup is adapted to perform measurements on stationary as well as transient processes. Spatial and temporal electron temperature and density profiles of a pure argon arc in the case of the GTAW process and argon arc with the presence of aluminum metal vapor in the case of the GMAW process were obtained. Additionally the data is used to estimate the concentration of the metal vapor in the GMAW plasma.

Atomic Processes and Diagnostics of Low Pressure Krypton Plasma

NASA Astrophysics Data System (ADS)

Srivastava, Rajesh; Goyal, Dipti; Gangwar, Reetesh; Stafford, Luc

2015-03-01

Optical emission spectroscopy along with suitable collisional-radiative (CR) model is used in plasma diagnostics. Importance of reliable cross-sections for various atomic processes is shown for low pressure argon plasma. In the present work, radially-averaged Kr emission lines from the 2pi --> 1sj were recorded as a function of pressure from 1 to 50mTorr. We have developed a CR model using our fine-structure relativistic-distorted wave cross sections. The various processes considered are electron-impact excitation, ionization and their reverse processes. The required rate coefficients have been calculated from these cross-sections assuming Maxwellian energy distribution. Electron temperature obtained from the CR model is found to be in good agreement with the probe measurements. Work is supported by IAEA Vienna, DAE-BRNS Mumbai and CSIR, New Delhi.

Diagnosing collisions of magnetized, high energy density plasma flows using a combination of collective Thomson scattering, Faraday rotation, and interferometry (invited)

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

Swadling, G. F., E-mail: swadling@imperial.ac.uk; Lebedev, S. V.; Hall, G. N.

2014-11-15

A suite of laser based diagnostics is used to study interactions of magnetised, supersonic, radiatively cooled plasma flows produced using the Magpie pulse power generator (1.4 MA, 240 ns rise time). Collective optical Thomson scattering measures the time-resolved local flow velocity and temperature across 7–14 spatial positions. The scattering spectrum is recorded from multiple directions, allowing more accurate reconstruction of the flow velocity vectors. The areal electron density is measured using 2D interferometry; optimisation and analysis are discussed. The Faraday rotation diagnostic, operating at 1053 nm, measures the magnetic field distribution in the plasma. Measurements obtained simultaneously by these diagnosticsmore » are used to constrain analysis, increasing the accuracy of interpretation.« less

Diagnostics of solar flare plasma on the basis of microwave emission

NASA Astrophysics Data System (ADS)

Granat, A. D.; Stepanov, A. V.; Tsvetkov, L. I.

The diagnostic possibilities of the new four-wavelength (1.95-, 2.25-, 2.8-, and 3.5-cm) polarimeter of the 22-m radio telescope of the Crimean Astrophysical Observatory is illustrated by two events, on November 2 and 12, 1988. The characteristics of the oscillation structure on November 2, 1988 are used to estimate the plasma density (about 7 x 10 exp -11/cu cm) and temperature (about 3 x 10 exp 7 K) of eruptive flare plasma as well as the mean magnetic field through the flare loop (about 400 Gs). The sequence of bursts of November 12, 1988 could have been caused by protuberance oscillations, which makes it possible to estimate the temperature of the active region (about 2.4 x 10 exp 6 K).

Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic

NASA Astrophysics Data System (ADS)

Swadling, G. F.; Ross, J. S.; Datte, P.; Moody, J.; Divol, L.; Jones, O.; Landen, O.

2016-11-01

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause "blanking" (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ˜8 J cm-2. This is significantly above the expected threshold for the onset of "blanking" effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate "blanking." Estimates suggest that an areal density of 1019 cm-2 Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

Determination of eddy current response with magnetic measurements.

PubMed

Jiang, Y Z; Tan, Y; Gao, Z; Nakamura, K; Liu, W B; Wang, S Z; Zhong, H; Wang, B B

2017-09-01

Accurate mutual inductances between magnetic diagnostics and poloidal field coils are an essential requirement for determining the poloidal flux for plasma equilibrium reconstruction. The mutual inductance calibration of the flux loops and magnetic probes requires time-varying coil currents, which also simultaneously drive eddy currents in electrically conducting structures. The eddy current-induced field appearing in the magnetic measurements can substantially increase the calibration error in the model if the eddy currents are neglected. In this paper, an expression of the magnetic diagnostic response to the coil currents is used to calibrate the mutual inductances, estimate the conductor time constant, and predict the eddy currents response. It is found that the eddy current effects in magnetic signals can be well-explained by the eddy current response determination. A set of experiments using a specially shaped saddle coil diagnostic are conducted to measure the SUNIST-like eddy current response and to examine the accuracy of this method. In shots that include plasmas, this approach can more accurately determine the plasma-related response in the magnetic signals by eliminating the field due to the eddy currents produced by the external field.

Heated probe diagnostic inside of the gas aggregation nanocluster source

NASA Astrophysics Data System (ADS)

Kolpakova, Anna; Shelemin, Artem; Kousal, Jaroslav; Kudrna, Pavel; Tichy, Milan; Biederman, Hynek; Surface; Plasma Science Team

2016-09-01

Gas aggregation cluster sources (GAS) usually operate outside common working conditions of most magnetrons and the size of nanoparticles created in GAS is below that commonly studied in dusty plasmas. Therefore, experimental data obtained inside the GAS are important for better understanding of process of nanoparticles formation. In order to study the conditions inside the gas aggregation chamber, special ``diagnostic GAS'' has been constructed. It allows simultaneous monitoring (or spatial profiling) by means of optical emission spectroscopy, mass spectrometry and probe diagnostic. Data obtained from Langmuir and heated probes map the plasma parameters in two dimensions - radial and axial. Titanium has been studied as an example of metal for which the reactive gas in the chamber starts nanoparticles production. Three basic situations were investigated: sputtering from clean titanium target in argon, sputtering from partially pre-oxidized target and sputtering with oxygen introduced into the discharge. It was found that during formation of nanoparticles the plasma parameters differ strongly from the situation without nanoparticles. These experimental data will support the efforts of more realistic modeling of the process. Czech Science Foundation 15-00863S.

Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic.

PubMed

Swadling, G F; Ross, J S; Datte, P; Moody, J; Divol, L; Jones, O; Landen, O

2016-11-01

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause "blanking" (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ∼8 J cm -2 . This is significantly above the expected threshold for the onset of "blanking" effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate "blanking." Estimates suggest that an areal density of 10 19 cm -2 Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.

PREFACE: The 8th Workshop on Frontiers in Low Temperature Plasma Diagnostics The 8th Workshop on Frontiers in Low Temperature Plasma Diagnostics

NASA Astrophysics Data System (ADS)

Sadeghi, Nader; Czarnetzki, Uwe

2010-03-01

The 8th Workshop on Frontiers in Low Temperature Plasma Diagnostics (FLTPD) was held in Blansko, near Brno, Czech Republic. FLTPD is a biennial European event in which scientists working on low temperature plasmas present their recent results, pointing out in particular the originality of the diagnostic techniques used. The idea of starting this series of workshops was born out of a discussion between Frieder Döbele, Bill Graham and one of us when travelling together from Bar Harbor, USA (after the 6th LAPD) to Montreal, Canada, in October 1993. It became evident that we had been lacking a European meeting that could bring together experts in the field of low temperature plasma diagnostics and facilitate sharing the knowledge of these diagnostics with a new generation of scientists. The first FLTPD was held in Les Houches, France, in February 1995. Since then it has been held in the spring of every other year in different European countries, as shown below. The next meeting will be held in Zinnowitz, near Greifswald, Germany, in May 2011. Year Location Chair of LOC 1995 Les Houches, France J Derouard 1997 Bad Honnef, Germany F Döbele 1999 Saillon, Switzerland Ch Hollenstein 2001 Rolduc, The Netherlands R van de Sanden 2003 Specchia, Italy S De Benedictis 2005 Les Houches, France N Sadeghi 2007 Cumbria, United Kingdom M Bowden 2009 Blansko, Czech Republic F Krčma To favour brainstorming and extended discussions between participants, FLTPD meetings have always been organized in isolated locations with the number of attendees limited to about 70. Workshops are held over three and a half days with about ten expert presentations by invited speakers (a few from overseas), as well as short oral or poster contributions. This special issue of Journal of Physics D: Applied Physics contains 20 articles representative of contributions to the last FLTPD in Blansko. All invited speakers and others who gave presentations, as selected by the Scientific Committee, were invited to submit a paper based on their contributions to the workshop. These final 20 articles, peer reviewed by the journal, will bring the 8th FLTPD to a wider audience. They represent a snapshot of current topics in low temperature plasma diagnostics. However, no attempt is made to give a full review of the field, which is in fact much wider and still rapidly developing. We hope, nevertheless, that the reader will find this compilation useful and stimulating for their research and that the special issue will serve as a convenient source of reference. Our special thanks go to the Scientific Committee for their important contributions to the success of the workshop in selecting invited speakers and other contributions to be published. We are also particularly grateful to the Editorial Board of Journal of Physics D: Applied Physics for the publication of this special issue.

Low-Molecular-Weight Plasma Proteome Analysis Using Top-Down Mass Spectrometry.

PubMed

Cheon, Dong Huey; Yang, Eun Gyeong; Lee, Cheolju; Lee, Ji Eun

2017-01-01

While human plasma has a wealth of diagnostic information regarding the state of the human body in heath and disease, low molecular weight (LMW) proteome (<30 kDa) has been shown to contain a rich source of diagnostic biomarkers. Here we describe a protocol for top-down proteomic analysis to identify and characterize the LMW proteoforms present in four types of human plasma samples without immunoaffinity depletion and with depletion of the top two, six, and seven high-abundance proteins. Each type of plasma sample was first fractionated based on molecular weight using gel-eluted liquid fraction entrapment electrophoresis (GELFrEE). Then, the GELFrEE fractions containing up to 30 kDa were subjected to nanocapillary-LC-MS/MS, and the high-resolution MS and MS/MS data were processed using ProSightPC software. As a result, a total of 442 LMW proteins and cleaved products, including those with posttranslational modifications (PTMs) and single amino acid variations (SAAVs), were identified with a threshold E-value of 1 × 10 -4 from the four types of plasma samples.

Measurement of Electron Density Using the Multipole Resonance Probe, Langmuir Probe and Optical Emission Spectroscopy in Low Pressure Plasmas with Different Electron Energy Distribution Functions

NASA Astrophysics Data System (ADS)

Oberberg, Moritz; Bibinov, Nikita; Ries, Stefan; Awakowicz, Peter; Institute of Electrical Engineering; Plasma Technology Team

2016-09-01

In recently publication, the young diagnostic tool Multipole Resonance Probe (MRP) for electron density measurements was introduced. It is based on active plasma resonance spectroscopy (APRS). The probe was simulated und evaluated for different devices. The geometrical and electrical symmetry simplifies the APRS model, so that the electron density can be easily calculated from the measured resonance. In this work, low pressure nitrogen mixture plasmas with different electron energy distribution functions (EEDF) are investigated. The results of the MRP measurement are compared with measurements of a Langmuir Probe (LP) and Optical Emission Spectroscopy (OES). Probes and OES measure in different regimes of kinetic electron energy. Both probes measure electrons with low kinetic energy (<10 eV), whereas the OES is influenced by electrons with high kinetic energy which are needed for transitions of molecule bands. By the determination of the absolute intensity of N2(C-B) and N2+(B-X)electron temperature and density can be calculated. In a non-maxwellian plasma, all plasma diagnostics need to be combined.

The injection of microorganisms into an atmospheric pressure rf-driven microplasma

NASA Astrophysics Data System (ADS)

Maguire, P. D.; Mahony, C. M. O.; Diver, D.; Mariotti, D.; Bennet, E.; Potts, H.; McDowell, D. A.

2013-09-01

The introduction of living organisms, such as bacteria, into atmospheric pressure microplasmas offers a unique means to study certain physical mechanisms in individual microorganisms and also help understand the impact of macroscopic entities and liquid droplets on plasma characteristics. We present the characterization of an RF-APD operating at 13.56 MHz and containing microorganisms in liquid droplets emitted from a nebulizer, with the spray entrained in a gas flow by a gas shroud and passed into the plasma source. We report successful microorganism injection and transmission through the plasma with stable plasma operation of at least one hour. Diagnostics include RF electrical characterization, optical emission spectrometry and electrostatic deflection to investigate microorganism charging. A close-coupled Impedans Octiv VI probe indicates source efficiencies of 10 to 15%. The introduction of the droplets/microorganisms results in increased plasma conductivity and reduced capacitance, due to their impact on electron density and temperature. An electrical model will be presented based on diagnostic data and deflection studies with input from simulations of charged aerosol diffusion and evaporation. Engineering and Physical Sciences Research Council EP/K006088, EP/K006142.

Plasma cell gingivitis - A rare case related to Colocasia (arbi) leaves

PubMed Central

Bali, Deepika; Gill, Sanjeet; Bali, Amit

2012-01-01

Plasma cell gingivitis is an uncommon inflammatory condition of uncertain etiology often flavoured chewing gum, spices, foods, candies, or dentifrices. The diagnosis of plasma cell gingivitis is based on comprehensive history taking, clinical examination, and appropriate diagnostic tests. Here we are presenting a rare case of plasma cell gingivitis caused by consumption of colocasia (arbi) leaves. Colocasia is a kind of vegetable, very commonly consumed in the regions of North India. PMID:23230358

Wavefront-sensor-based electron density measurements for laser-plasma accelerators.

PubMed

Plateau, G R; Matlis, N H; Geddes, C G R; Gonsalves, A J; Shiraishi, S; Lin, C; van Mourik, R A; Leemans, W P

2010-03-01

Characterization of the electron density in laser produced plasmas is presented using direct wavefront analysis of a probe laser beam. The performance of a laser-driven plasma-wakefield accelerator depends on the plasma wavelength and hence on the electron density. Density measurements using a conventional folded-wave interferometer and using a commercial wavefront sensor are compared for different regimes of the laser-plasma accelerator. It is shown that direct wavefront measurements agree with interferometric measurements and, because of the robustness of the compact commercial device, offer greater phase sensitivity and straightforward analysis, improving shot-to-shot plasma density diagnostics.

Wavefront-sensor-based electron density measurements for laser-plasma accelerators

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

Plateau, Guillaume; Matlis, Nicholas; Geddes, Cameron

2010-02-20

Characterization of the electron density in laser produced plasmas is presented using direct wavefront analysis of a probe laser beam. The performance of a laser-driven plasma-wakefield accelerator depends on the plasma wavelength, hence on the electron density. Density measurements using a conventional folded-wave interferometer and using a commercial wavefront sensor are compared for different regimes of the laser-plasma accelerator. It is shown that direct wavefront measurements agree with interferometric measurements and, because of the robustness of the compact commercial device, have greater phase sensitivity, straightforward analysis, improving shot-to-shot plasma-density diagnostics.

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

Kim, Dong-Hwan; Hong, Suk-Ho; National Fusion Research Institute

Plasma characteristics in the far scrape-off layer region of tokamak play a crucial role in the stable plasma operation and its sustainability. Due to the huge facility, electrical diagnostic systems to measure plasma properties have extremely long cable length resulting in large stray current. To overcome this problem, a sideband harmonic method was applied to the Korea Superconducting Tokamak Advanced Research tokamak plasma. The sideband method allows the measurement of the electron temperature and the plasma density without the effect of the stray current. The measured plasma densities are compared with those from the interferometer, and the results show reliabilitymore » of the method.« less

Development of a new virtual diagnostic for V3FIT

NASA Astrophysics Data System (ADS)

Trevisan, G. L.; Cianciosa, M. R.; Terranova, D.; Hanson, J. D.

2014-12-01

The determination of plasma equilibria from diagnostic information is a fundamental issue. V3FIT is a fully three-dimensional reconstruction code capable of solving the inverse problem using both magnetic and kinetic measurements. It uses VMEC as core equilibrium solver and supports both free- and fixed-boundary reconstruction approaches. In fixed-boundary mode VMEC does not use explicit information about currents in external coils, even though it has important effects on the shape of the safety factor profile. Indeed, the edge safety factor influences the reversal position in RFP plasmas, which then determines the position of the m = 0 island chain and the edge transport properties. In order to exploit such information a new virtual diagnostic has been developed, that thanks to Ampère's law relates the external current through the center of the torus to the circulation of the toroidal magnetic field on the outermost flux surface. The reconstructions that exploit the new diagnostic are indeed found to better interpret the experimental data with respect to edge physics.

Plasma Diagnostics For The Investigation of Silane Based Glow Discharge Deposition Processes

NASA Astrophysics Data System (ADS)

Mataras, Dimitrios

2001-10-01

In this work is presented the study of microcrystalline silicon PECVD process through highly diluted silane in hydrogen discharges. The investigation is performed by applying different non intrusive plasma diagnostics (electrical, optical, mass spectrometric and laser interferometric measurements). Each of these measurements is related to different plasma sub-processes (gas physics, plasma chemistry and plasma surface interaction) and compose a complete set, proper for the investigation of the effect of external discharge parameters on the deposition processes. In the specific case these plasma diagnostics are applied for prospecting the optimal experimental conditions from the ic-Si:H deposition rate point of view. Namely, the main characteristics of the effect of frequency, discharge geometry, power consumption and total gas pressure on the deposition process are presented successively. Special attention is given to the study of the frequency effect (13.56 MHz 50 MHz) indicating that the correct way to compare results of different driving frequency discharges is by maintaining constant the total power dissipation in the discharge. The important role of frequency in the achievement of high deposition rates and on the optimization of all other parameters is underlined. Finally, the proper combination of experimental conditions that result from the optimal choice of each of the above-mentioned discharge parameters and lead to high microcrystalline silicon deposition rates (7.5 Å/sec) is presented. The increase of silane dissociation rate towards neutral radicals (frequency effect), the contribution of highly sticking to the surface radicals (discharge geometry optimum) and the controlled production of higher radicals through secondary gas phase reactions (total gas pressure), are presented as prerequisites for the achievement of high deposition rates.

Plasma Neutrophil Gelatinase-Associated Lipocalin diagnosed acute kidney injury in patients with systemic inflammatory disease and sepsis.

PubMed

Md Ralib, Azrina; Mat Nor, Mohd Basri; Pickering, John W

2017-05-01

Sepsis is the leading cause of intensive care unit (ICU) admission. Plasma Neutrophil Gelatinase Associated-Lipocalin (NGAL) is a promising biomarker for acute kidney injury (AKI) detection; however, it is also increased with inflammation and few studies have been conducted in non-Caucasian populations and/or in developing economies. Therefore, we evaluated plasma NGAL's diagnostic performance in the presence of sepsis and systemic inflammatory response syndrome (SIRS) in a Malaysian ICU cohort. This is a prospective observational study on patients with SIRS. Plasma creatinine (pCr) and NGAL were measured on ICU admission. Patients were classified according to the occurrence of AKI and sepsis. Of 225 patients recruited, 129 (57%) had sepsis of whom 67 (52%) also had AKI. 96 patients (43%) had non-infectious SIRS, of whom 20 (21%) also had AKI. NGAL concentrations were higher in AKI patients within both the sepsis and non-infectious SIRS cohorts (both P < 0.0001). The diagnostic area under curve for AKI was 0.81 (95%CI: 0.74 to 0.87). The optimal cut-off was higher in sepsis compared to non-infectious SIRS patients (454 versus 176 ng/mL). Addition of NGAL to a clinical model comprising age, pCr, medical admission category and SAPS II score increased the mean risk of those with AKI by 4% and reduced the mean risk of those without AKI by 3%. Acute kidney injury is more common with sepsis than non-infectious SIRS. Plasma NGAL was diagnostic of AKI in both subgroups. The optimal cut-off for diagnosing AKI was higher in sepsis than in non-infectious SIRS. Addition of plasma NGAL improved the clinical model used to diagnose AKI. © 2016 Asian Pacific Society of Nephrology.

ECR plasma thruster research - Preliminary theory and experiments

NASA Technical Reports Server (NTRS)

Sercel, Joel C.; Fitzgerald, Dennis J.

1989-01-01

A preliminary theory of the operation of the electron-cyclotron-resonance (ECR) plasma thruster is described along with an outline of recent experiments. This work is presented to communicate the status of an ongoing research effort directed at developing a unified theory to quantitatively describe the operation of the ECR plasma thruster. The theory is presented as a set of nonlinear ordinary differential equations and boundary conditions which describe the plasma density, velocity, and electron temperature. Diagnostic tools developed to measure plasma conditions in the existing research device are described.

Heat flux estimates of power balance on Proto-MPEX with IR imaging

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

Showers, M., E-mail: mshower1@vols.utk.edu; Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831; Biewer, T. M.

The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) at Oak Ridge National Laboratory (ORNL) is a precursor linear plasma device to the Material Plasma Exposure eXperiment (MPEX), which will study plasma material interactions (PMIs) for future fusion reactors. This paper will discuss the initial steps performed towards completing a power balance on Proto-MPEX to quantify where energy is lost from the plasma, including the relevant diagnostic package implemented. Machine operating parameters that will improve Proto-MPEX’s performance may be identified, increasing its PMI research capabilities.

Data management software concept for WEST plasma measurement system

NASA Astrophysics Data System (ADS)

Zienkiewicz, P.; Kasprowicz, G.; Byszuk, A.; Wojeński, A.; Kolasinski, P.; Cieszewski, R.; Czarski, T.; Chernyshova, M.; Pozniak, K.; Zabolotny, W.; Juszczyk, B.; Mazon, D.; Malard, P.

2014-11-01

This paper describes the concept of data management software for the multichannel readout system for the GEM detector used in WEST Plasma experiment. The proposed system consists of three separate communication channels: fast data channel, diagnostics channel, slow data channel. Fast data channel is provided by the FPGA with integrated ARM cores providing direct readout data from Analog Front Ends through 10GbE with short, guaranteed intervals. Slow data channel is provided by multiple, fast CPUs after data processing with detailed readout data with use of GNU/Linux OS and appropriate software. Diagnostic channel provides detailed feedback for control purposes.

Signal evaluations using singular value decomposition for Thomson scattering diagnostics.

PubMed

Tojo, H; Yamada, I; Yasuhara, R; Yatsuka, E; Funaba, H; Hatae, T; Hayashi, H; Itami, K

2014-11-01

This paper provides a novel method for evaluating signal intensities in incoherent Thomson scattering diagnostics. A double-pass Thomson scattering system, where a laser passes through the plasma twice, generates two scattering pulses from the plasma. Evaluations of the signal intensities in the spectrometer are sometimes difficult due to noise and stray light. We apply the singular value decomposition method to Thomson scattering data with strong noise components. Results show that the average accuracy of the measured electron temperature (Te) is superior to that of temperature obtained using a low-pass filter (<20 MHz) or without any filters.

Signal evaluations using singular value decomposition for Thomson scattering diagnostics

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

Tojo, H., E-mail: tojo.hiroshi@jaea.go.jp; Yatsuka, E.; Hatae, T.

2014-11-15

This paper provides a novel method for evaluating signal intensities in incoherent Thomson scattering diagnostics. A double-pass Thomson scattering system, where a laser passes through the plasma twice, generates two scattering pulses from the plasma. Evaluations of the signal intensities in the spectrometer are sometimes difficult due to noise and stray light. We apply the singular value decomposition method to Thomson scattering data with strong noise components. Results show that the average accuracy of the measured electron temperature (T{sub e}) is superior to that of temperature obtained using a low-pass filter (<20 MHz) or without any filters.

ACCURACY OF PLASMA FREE METANEPHRINES IN THE DIAGNOSIS OF PHEOCHROMOCYTOMA AND PARAGANGLIOMA: A SYSTEMATIC REVIEW AND META-ANALYSIS.

PubMed

Chen, Yan; Xiao, Huangmeng; Zhou, Xieda; Huang, Xiaoyu; Li, Yanbing; Xiao, Haipeng; Cao, Xiaopei

2017-10-01

Various studies have validated plasma free metanephrines (MNs) as biomarkers for pheochromocytoma and paraganglioma (PPGL). This meta-analysis aimed to estimate the overall diagnostic accuracy of this biochemical test for PPGL. We searched the PubMed, the Cochrane Library, Web of Science, Embase, Scopus, OvidSP, and ProQuest Dissertations & Theses databases from January 1, 1995 to December 2, 2016 and selected studies written in English that assessed plasma free MNs in the diagnosis of PPGL. Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) was used to evaluate the quality of the included studies. We calculated pooled sensitivities, specificities, positive and negative likelihood ratios, diagnostic odds ratios (DORs) and areas under curve (AUCs) with their 95% confidence intervals (95% CIs). Heterogeneity was assessed by I 2 . To identify the source of heterogeneity, we evaluated the threshold effect and performed a meta-regression. Deeks' funnel plot was selected for investigating any potential publication bias. Although the combination of metanephrine (MN) and normetanephrine (NMN) carried lower specificity (0.94, 95% CI 0.90-0.97) than NMN (0.97, 95% CI 0.92-0.99), NMN was generally more accurate than individual tests, with the highest AUC (0.99, 95% CI 0.97-0.99), DOR (443.35, 95% CI 216.9-906.23), and pooled sensitivity (0.97, 95% CI 0.94-0.98) values. Threshold effect and meta-regression analyses showed that different cut-offs, blood sampling positions, study types and test methods contributed to heterogeneity. This meta-analysis suggested an effective value for combined plasma free MNs for the diagnosis of PPGL, but testing for MNs requires more standardization using tightly regulated studies. AUC = area under curve; CI = confidence interval; DOR = diagnostic odds ratio; EIA = enzyme immunoassay; LC-ECD = liquid chromatography-electrochemical detection; LC-MS/MS = liquid chromatography-tandem mass spectrometry; MN = metanephrine; NMN = normetaneprhine; PPGL = pheochromocytoma and paraganglioma; QUADAS-2 = Quality Assessment of Diagnostic Accuracy Studies 2.

Special issue: diagnostics of atmospheric pressure microplasmas

NASA Astrophysics Data System (ADS)

Bruggeman, Peter; Czarnetzki, Uwe; Tachibana, Kunihide

2013-11-01

In recent decades, a strong revival of non-equilibrium atmospheric pressure plasma studies has developed in the form of microplasmas. Microplasmas have typical scales of 1 mm or less and offer a very exciting research direction in the field of plasma science and technology as the discharge physics can be considerably different due to high collisionality and the importance of plasma-surface interaction. These high-pressure small-scale plasmas have a diverse range of physical and chemical properties. This diversity coincides with various applications including light/UV sources [1], material processing [2], chemical analysis [3], material synthesis [4], electromagnetics [5], combustion [6] and even medicine [7]. At atmospheric pressure, large scale plasmas have the tendency to become unstable due to the high collision rates leading to enhanced heating and ionization compared to their low-pressure counterparts. As low-pressure plasmas typically operate in reactors with sizes of tens of centimetres, scaling up the pressure to atmospheric pressure the size of the plasma reduces to typical sizes below 1 mm. A natural approach of stabilizing atmospheric pressure plasmas is thus the use of microelectrode geometries. Traditionally microplasmas have been produced in confined geometries which allow one to stabilize dc excited discharges. This stabilization is intrinsically connected to the large surface-to-volume ratio which enhances heat transfer and losses of charged and excited species to the walls. Currently challenging boundaries are pushed by producing microcavity geometries with dimensions of the order of 1 µm [8]. The subject of this special issue, diagnostics of microplasmas, is motivated by the many challenges in microplasma diagnostics in view of the complex chemistry and strong spatial (and even temporal) gradients of species densities and plasma properties. Atmospheric pressure plasmas have a very long history dating back more than 100 years, with early work of, e.g. Werner von Siemens [9], who studied a dielectric barrier discharge (DBD) in the context of ozone generation. DBD discharges often consist of numerous filamentary discharges which are inherently transient in nature and with a characteristic size similar to the dimensions of microplasmas. Several groups are investigating the stabilization of such plasma filaments to perform temporal and spatial resolved diagnostics. To this end and due to the many similar challenges for diagnostics, this type of discharge is also included in this special issue. Research on microplasmas is performed in many groups spread all over the world, and a biannual workshop is devoted to the topic. The 7th edition of this International Workshop on Microplasmas was held in Beijing in May 2013. Large research programs consisting of clusters of research labs such as in Japan, Germany, France and the USA have been producing a wealth of information available in the literature. As the editors of this special issue, we are very pleased to have attracted a collection of excellent papers from leading experts in the field covering most of the current diagnostics performed in microplasmas. As an introduction to the regular special issue papers, a review paper is included [10]. It describes the key characteristics of atmospheric pressure plasmas and microplasmas in particular, and reviews the state of the art in plasma diagnostics. Special attention has been given in this review to highlighting the issues and challenges to probe microplasmas. The regular papers cover a large range of different diagnostics including coherent anti-Stokes Raman scattering (CARS) [11], (two-photon) laser induced fluorescence ((Ta)LIF) [12, 13, 18, 24], absorption spectroscopy [13-18], optical emission spectroscopy [12, 16-21, 24], imaging [22, 23], surface diagnostics [24, 25] and mass spectrometry [26, 27]. Different aspects of microplasmas are broadly investigated from a perspective of diagnostics, modelling and applications. Diagnostics are pivotal to both the development of models and the optimization and exploration of novel applications. Consequently, this special issue is focused on the various aspects and challenges for diagnostics in microplasmas. In addition, previous special issues on the topic of microplasmas have already covered many aspects of source development, applications and modelling [28-31]. The reader who wishes to access additional background information on microplasmas is referred to the following review papers [32-35]. We would like to thank all the contributors and the editorial staff who were of tremendous support in the preparation of this special issue. It is our sincere hope that you enjoy reading this special issue and that it will be a reference and helpful guidance for young researchers embarking in the field of microplasmas. The continued effort to increase our understanding of plasmas by modelling and diagnostics is of key importance for plasma science and the development of novel technologies. References [1] Eden J G, Park S-J, Herring C M and Bulson J M 2011 J. Phys. D: Appl. Phys. 44 224011 [2] Lucas N, Ermel V, Kurrat M and Buttgenbach S 2008 J. Phys. D: Appl. Phys. 41 215202 [3] Karnassios V 2004 Spectrochim. Acta B 59 909-28 [4] Mariotti D and Sankaran RM 2010 J. Phys. D: Appl. Phys. 43 323001 [5] Sakai O and Tachibana K 2012 Plasma Sources Sci. Technol. 21 013001 [6] Starikovskaia S M 2006 Plasma assisted ignition and combustion J. Phys. D.: Appl. Phys. 39 R265-99 [7] Fridman G, Friedman G, Gutsol A, Shekhter A B, Vasilets V N and Fridman A 2008 Plasma Process. Polym. 5 503-33 [8] Eden G et al 2013 IEEE Trans. Plasma Sci. 41 661-75 [9] Siemens W 1857 Poggendorffs. Ann. Phys. Chem. 102 66-122 [10] Bruggeman P and Brandenburg R 2013 J. Phys. D: Appl. Phys. 46 464001 [11] Montello A et al 2013 J. Phys. D: Appl. Phys. 46 464002 [12] Schröder D et al 2013 J. Phys. D: Appl. Phys. 46 464003 [13] Verreycken T et al 2013 J. Phys. D: Appl. Phys. 46 464004 [14] Sousa J S and Puech V 2013 J. Phys. D: Appl. Phys. 46 464005 [15] Takeda K et al 2013 J. Phys. D: Appl. Phys. 46 464006 [16] Vallade J and Massines F 2013 J. Phys. D: Appl. Phys. 46 464007 [17] Wang C and Wu W 2013 J. Phys. D: Appl. Phys. 46 464008 [18] Schröter S et al 2013 J. Phys. D: Appl. Phys. 46 464009 [19] Rusterholtz D L et al 2013 J. Phys. D: Appl. Phys. 46 464010 [20] Huang B-D et al 2013 J. Phys. D: Appl. Phys. 46 464011 [21] Pothiraja R et al 2013 J. Phys. D: Appl. Phys. 46 464012 [22] Marinov I et al 2013 J. Phys. D: Appl. Phys. 46 464013 [23] Akishev Y et al 2013 J. Phys. D: Appl. Phys. 46 464014 [24] Brandenburg R et al 2013 J. Phys. D: Appl. Phys. 46 464015 [25] Houlahan T J Jret al 2013 J. Phys. D: Appl. Phys. 46 464016 [26] Benedikt J et al 2013 J. Phys. D: Appl. Phys. 46 464017 [27] McKay K et al 2013 J. Phys. D: Appl. Phys. 46 464018 [28] Selected papers from the 2nd International Workshop on Microplasmas 2005 J. Phys. D: Appl. Phys. 38 1633-759 [29] Special issue: 3rd International Workshop on Microplasmas 2007 Control. Plasma Phys. 47 3-128 [30] Cluster issue on Microplasmas: 4th International Workshop on Microplasmas 2008 J. Phys. D: Appl. Phys. 41 1904001 [31] Microplasmas: scientific challenges and technological opportunities 2010 Eur. Phys. J. D 60 437-608 [32] Becker K H, Schoenbach K H and Eden J G 2006 J. Phys. D: Appl. Phys. 39 R55 [33] Iza F, Kim G J, Lee S M, Lee J K, Walsh J L, Zhang Y T and Kong M G 2008 Plasma Process. Polym. 5 322-44 [34] Tachibana K 2006 Trans. Electr. Electron. Eng. 1 145-55 [35] Samukawa S et al 2012 J. Phys. D: Appl. Phys. 45 253001

New developments in the diagnostics for the fusion products on JET in preparation for ITER (invited).

PubMed

Murari, A; Angelone, M; Bonheure, G; Cecil, E; Craciunescu, T; Darrow, D; Edlington, T; Ericsson, G; Gatu-Johnson, M; Gorini, G; Hellesen, C; Kiptily, V; Mlynar, J; Perez von Thun, C; Pillon, M; Popovichev, S; Syme, B; Tardocchi, M; Zoita, V L

2010-10-01

Notwithstanding the advances of the past decades, significant developments are still needed to satisfactorily diagnose “burning plasmas.” D–T plasmas indeed require a series of additional measurements for the optimization and control of the configuration: the 14 MeV neutrons, the isotopic composition of the main plasma, the helium ash, and the redistribution and losses of the alpha particles. Moreover a burning plasma environment is in general much more hostile for diagnostics than purely deuterium plasmas. Therefore, in addition to the development and refinement of new measuring techniques, technological advances are also indispensable for the proper characterization of the next generation of devices. On JET an integrated program of diagnostic developments, for JET future and in preparation for ITER, has been pursued and many new results are now available. In the field of neutron detection, the neutron spectra are now routinely measured in the energy range of 1–18 MeV by a time of flight spectrometer and they have allowed studying the effects of rf heating on the fast ions. A new analysis method for the interpretation of the neutron cameras measurements has been refined and applied to the data of the last trace tritium campaign (TTE). With regard to technological upgrades, chemical vapor deposition diamond detectors have been qualified both as neutron counters and as neutron spectrometers, with a potential energy resolution of about one percent. The in situ calibration of the neutron diagnostics, in preparation for the operation with the ITER-like wall, is also promoting important technological developments. With regard to the fast particles, for the first time the temperature of the fast particle tails has been obtained with a new high purity Germanium detector measuring the gamma emission spectrum from the plasma. The effects of toroidal Alfven eigenmodes modes and various MHD instabilities on the confinement of the fast particles have been determined with a combination of gamma ray cameras, neutral particle analyzers, scintillator probe, and Faraday cups. From a more technological perspective, various neutron filters have been tested to allow measurement of the gamma ray emission also at high level of neutron yield.

New developments in the diagnostics for the fusion products on JET in preparation for ITER (invited)

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

Murari, A.; Angelone, M.; Pillon, M.

Notwithstanding the advances of the past decades, significant developments are still needed to satisfactorily diagnose ''burning plasmas.'' D-T plasmas indeed require a series of additional measurements for the optimization and control of the configuration: the 14 MeV neutrons, the isotopic composition of the main plasma, the helium ash, and the redistribution and losses of the alpha particles. Moreover a burning plasma environment is in general much more hostile for diagnostics than purely deuterium plasmas. Therefore, in addition to the development and refinement of new measuring techniques, technological advances are also indispensable for the proper characterization of the next generation ofmore » devices. On JET an integrated program of diagnostic developments, for JET future and in preparation for ITER, has been pursued and many new results are now available. In the field of neutron detection, the neutron spectra are now routinely measured in the energy range of 1-18 MeV by a time of flight spectrometer and they have allowed studying the effects of rf heating on the fast ions.A new analysis method for the interpretation of the neutron cameras measurements has been refined and applied to the data of the last trace tritium campaign (TTE). With regard to technological upgrades, chemical vapor deposition diamond detectors have been qualified both as neutron counters and as neutron spectrometers, with a potential energy resolution of about one percent. The in situ calibration of the neutron diagnostics, in preparation for the operation with the ITER-like wall, is also promoting important technological developments. With regard to the fast particles, for the first time the temperature of the fast particle tails has been obtained with a new high purity Germanium detector measuring the gamma emission spectrum from the plasma. The effects of toroidal Alfven eigenmodes modes and various MHD instabilities on the confinement of the fast particles have been determined with a combination of gamma ray cameras, neutral particle analyzers, scintillator probe, and Faraday cups. From a more technological perspective, various neutron filters have been tested to allow measurement of the gamma ray emission also at high level of neutron yield.« less

Plasma free versus deconjugated metanephrines for diagnosis of phaeochromocytoma

PubMed Central

Pamporaki, Christina; Därr, Roland; Bursztyn, Michael; Stephan, Glöckner; Bornstein, Stefan R.; Lenders, Jacques W.M.; Pacak, Karel; Krinner, Axel; Eisenhofer, Graeme

2013-01-01

Summary Background Diagnosis of phaeochromocytoma is commonly performed by measurements of plasma free normetanephrine and metanephrine. Plasma deconjugated normetanephrine and metanephrine have been proposed as alternative equivalent, but easier to measure biomarkers. Objective The aim of this study was to compare the diagnostic performances of plasma free versus deconjugated normetanephrine and metanephrine in patients tested for phaeochromocytoma. Methods The study population included a reference group of 262 normotensive and hypertensive volunteers, 198 patients with phaeochromocytoma and 528 patients initially suspected of having the tumour, but with negative investigations after at least 2 years of follow up. Measurements were performed using liquid chromatography with electrochemical detection. Results Median plasma concentrations of free normetanephrine were 17-fold higher in patients with phaeochromocytoma than in the reference population, a 72% larger (p<0.001) difference than that for the 10-fold higher levels of plasma deconjugated normetanephrine. In contrast, relative increases of plasma concentrations of free and deconjugated metanephrine were similar. Using upper cut-offs established in the reference population, measurements of plasma free metabolites provided superior diagnostic performance than deconjugated metabolites according to measures of both sensitivity (97% vs 92%, p=0.002) and specificity (93 vs 89%, p=0.012). The area under the receiver operating characteristic curve for the free metabolites was larger than that for the deconjugated metabolites (0.986 vs 0.965, p<0.001). Conclusion Measurements of plasma free normetanephrine and metanephrine are superior to the deconjugated metabolites for diagnosis of phaeochromocytoma. PMID:23461656

Studies of RF sheaths and diagnostics on IShTAR

NASA Astrophysics Data System (ADS)

Crombé, K.; Devaux, S.; D'Inca, R.; Faudot, E.; Faugel, H.; Fünfgelder, H.; Heuraux, S.; Jacquot, J.; Louche, F.; Moritz, J.; Ochoukov, R.; Tripsky, M.; Van Eester, D.; Wauters, T.; Noterdaeme, J.-M.

2015-12-01

IShTAR (Ion cyclotron Sheath Test ARrangement) is a linear magnetised plasma test facility for RF sheaths studies at the Max-Planck-Institut für Plasmaphysik in Garching. In contrast to a tokamak, a test stand provides more liberty to impose the parameters and gives better access for the instrumentation and antennas. The project will support the development of diagnostic methods for characterising RF sheaths and validate and improve theoretical predictions. The cylindrical vacuum vessel has a diameter of 1 m and is 1.1 m long. The plasma is created by an external cylindrical plasma source equipped with a helical antenna that has been designed to excite the m=1 helicon mode. In inductive mode, plasma densities and electron temperatures have been characterised with a planar Langmuir probe as a function of gas pressure and input RF power. A 2D array of RF compensated Langmuir probes and a spectrometer are planned. A single strap RF antenna has been designed; the plasma-facing surface is aligned to the cylindrical plasma to ease the modelling. The probes will allow direct measurements of plasma density profiles in front of the RF antenna, and thus a detailed study of the density modifications induced by RF sheaths, which influences the coupling. The RF antenna frequency has been chosen to study different plasma wave interactions: the accessible plasma density range includes an evanescent and propagative behaviour of slow or fast waves, and allows the study of the effect of the lower hybrid resonance layer.

Experimental results from plasma transport on Prototype-Material Plasma Exposure eXperiment and comparison with B2-Eirene modeling

NASA Astrophysics Data System (ADS)

Kafle, N.; Caneses, J. F.; Biewer, T. M.; Owen, L.; Showers, M.; Donovan, D.; Caughman, J. B.; Goulding, R. H.; Rapp, Juergen

2017-10-01

Proto-MPEX at ORNL is a linear plasma device that combines a helicon plasma source with additional microwave and RF heating to deliver high plasma heat and particle fluxes to a target. Double Langmuir probes and Thomson scattering are being used to measure local Te and ne at various radial and axial locations. A recently constructed Mach- double probe provides the added capability of simultaneously measuring Te, ne, and Mach number. With this diagnostic, it is possible to infer the plasma flow, particle flux, and convective heat flux at different locations along the plasma column in Proto-MPEX. Preliminary results show Mach numbers of 0.6 and 0.8 in either direction away from the helicon source, and no flow near the source for the case where the peak magnetic field was 1.0 T. In addition, the Thomson Scattering system has been upgraded to measure ne and Te profiles at two axial locations, upstream at the electron heating location and downstream close to the target. Measurements of particle flow and flux profiles, heat flux, and profiles of ne and Te will be discussed. The extensive coverage provided by these diagnostics permits data-constrained B2-Eirene modeling of the entire plasma column, and comparison with results of modeling of high density mode plasmas will be presented. Supported by the US. D.O.E. contract DE-AC05-00OR22725.

IONIZATION EQUILIBRIUM TIMESCALES IN COLLISIONAL PLASMAS

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

Smith, Randall K.; Hughes, John P., E-mail: rsmith@cfa.harvard.ed, E-mail: jph@physics.rutgers.ed

2010-07-20

Astrophysical shocks or bursts from a photoionizing source can disturb the typical collisional plasma found in galactic interstellar media or the intergalactic medium. The spectrum emitted by this plasma contains diagnostics that have been used to determine the time since the disturbing event, although this determination becomes uncertain as the elements in the plasma return to ionization equilibrium. A general solution for the equilibrium timescale for each element arises from the elegant eigenvector method of solution to the problem of a non-equilibrium plasma described by Masai and Hughes and Helfand. In general, the ionization evolution of an element Z inmore » a constant electron temperature plasma is given by a coupled set of Z + 1 first-order differential equations. However, they can be recast as Z uncoupled first-order differential equations using an eigenvector basis for the system. The solution is then Z separate exponential functions, with the time constants given by the eigenvalues of the rate matrix. The smallest of these eigenvalues gives the scale of the slowest return to equilibrium independent of the initial conditions, while conversely the largest eigenvalue is the scale of the fastest change in the ion population. These results hold for an ionizing plasma, a recombining plasma, or even a plasma with random initial conditions, and will allow users of these diagnostics to determine directly if their best-fit result significantly limits the timescale since a disturbance or is so close to equilibrium as to include an arbitrarily long time.« less

Clinical validation of a novel diagnostic HIV-2 total nucleic acid qualitative assay using the Abbott m2000 platform: Implications for complementary HIV-2 nucleic acid testing for the CDC 4th generation HIV diagnostic testing algorithm.

PubMed

Chang, Ming; Wong, Audrey J S; Raugi, Dana N; Smith, Robert A; Seilie, Annette M; Ortega, Jose P; Bogusz, Kyle M; Sall, Fatima; Ba, Selly; Seydi, Moussa; Gottlieb, Geoffrey S; Coombs, Robert W

2017-01-01

The 2014 CDC 4th generation HIV screening algorithm includes an orthogonal immunoassay to confirm and discriminate HIV-1 and HIV-2 antibodies. Additional nucleic acid testing (NAT) is recommended to resolve indeterminate or undifferentiated HIV seroreactivity. HIV-2 NAT requires a second-line assay to detect HIV-2 total nucleic acid (TNA) in patients' blood cells, as a third of untreated patients have undetectable plasma HIV-2 RNA. To validate a qualitative HIV-2 TNA assay using peripheral blood mononuclear cells (PBMC) from HIV-2-infected Senegalese study participants. We evaluated the assay precision, sensitivity, specificity, and diagnostic performance of an HIV-2 TNA assay. Matched plasma and PBMC samples were collected from 25 HIV-1, 30 HIV-2, 8 HIV-1/-2 dual-seropositive and 25 HIV seronegative individuals. Diagnostic performance was evaluated by comparing the outcome of the TNA assay to the results obtained by the 4th generation HIV screening and confirmatory immunoassays. All PBMC from 30 HIV-2 seropositive participants tested positive for HIV-2 TNA including 23 patients with undetectable plasma RNA. Of the 30 matched plasma specimens, one was HIV non-reactive. Samples from 50 non-HIV-2 infected individuals were confirmed as non-reactive for HIV-2 Ab and negative for HIV-2 TNA. The agreement between HIV-2 TNA and the combined immunoassay results was 98.8% (79/80). Furthermore, HIV-2 TNA was detected in 7 of 8 PBMC specimens from HIV-1/HIV-2 dual-seropositive participants. Our TNA assay detected HIV-2 DNA/RNA in PBMC from serologically HIV-2 reactive, HIV indeterminate or HIV undifferentiated individuals with undetectable plasma RNA, and is suitable for confirming HIV-2 infection in the HIV testing algorithm. Copyright © 2016 Elsevier B.V. All rights reserved.

Miniaturized Plasma and Neutral Diagnostics for JIMO

NASA Technical Reports Server (NTRS)

McHarg, M. G.; Enloe, C. L.; Krause, L. A.; Herrero, F. A.

2003-01-01

We describe a miniaturized suite of instruments which provides both bulk energy resolved plasma properties and coarse neutral mass spectroscopy suitable for measurements on the Jupiter Icy Moons Orbiter (JIMO). The suite is comprised of two instruments; the Miniaturized Electro-Static Analyzer (MESA), and the Flat Plasma Spectrometer (FLAPS), designed to measure the near earth environment on the Air Force Academy small satellite missions Falconsat-2 and 3.

Space experiments with particle accelerators

NASA Technical Reports Server (NTRS)

Obayashi, T.; Kawashima, N.; Kuriki, K.; Nagatomo, M.; Ninomiya, K.; Sasaki, S.; Roberts, W. T.; Chappell, C. R.; Reasoner, D. L.; Garriott, O. K.;

Forbidden line emission from highly ionized atoms in tokamak plasmas

NASA Technical Reports Server (NTRS)

Feldman, U.; Doschek, G. A.; Bhatia, A. K.

1982-01-01

Considerable interest in the observation of forbidden spectral lines from highly ionized atoms in tokamak plasmas is related to the significance of such observations for plasma diagnostic applications. Atomic data for the elements Ti Cr, Mn, Fe, Ni, and Kr have been published by Feldman et al. (1980) and Bhatia et al. (1980). The present investigation is concerned with collisional excitation rate coefficients and radiative decay rates, which are interpolated for ions of elements between calcium, and krypton and for levels of the 2s2 2pk, 2s 2p(k+1), and 2p(k+2) configurations, and for the O I, N I, C I, B I, and Be I isoelectronic sequences. The provided interpolated atomic data can be employed to calculate level populations and relative line intensities for ions of the considered sequences, taking into account levels of the stated configurations. Important plasma diagnostic information provided by the forbidden lines includes the ion temperature

Dynamical transitions associated with turbulence in a helicon plasma

NASA Astrophysics Data System (ADS)

Light, Adam D.; Tian, Li; Chakraborty Thakur, Saikat; Tynan, George R.

2017-10-01

Diagnostic capabilities are often cited as a limiting factor in our understanding of transport in fusion devices. Increasingly advanced multichannel diagnostics are being applied to classify transport regimes and to search for ``trigger'' features that signal an oncoming dynamical event, such as an ELM or an L-H transition. In this work, we explore a technique that yields information about global properties of plasma dynamics from a single time series of a relevant plasma quantity. Electrostatic probe data from the Controlled Shear Decorrelation eXperiment (CSDX) is analyzed using recurrence quantification analysis (RQA) in the context of previous work on the transition to weak drift-wave turbulence. The recurrence characteristics of a phase space trajectory provide a quantitative means to classify dynamics and identify transitions in a complex system. We present and quantify dynamical variations in the plasma variables as a function of the background magnetic field strength. A dynamical transition corresponding to the emergence of broadband fluctuations is identified using RQA measures.

Schlieren, Phase-Contrast, and Spectroscopy Diagnostics for the LBNL HIF Plasma Channel Experiment

NASA Astrophysics Data System (ADS)

Ponce, D. M.; Niemann, C.; Fessenden, T. J.; Leemans, W.; Vandersloot, K.; Dahlbacka, G.; Yu, S. S.; Sharp, W. M.; Tauschwitz, A.

1999-11-01

The LBNL Plasma Channel experiment has demonstrated stable 42-cm Z-pinch discharge plasma channels with peak currents in excess of 50 kA for a 7 torr nitrogen, 30 kV discharge. These channels offer the possibility of transporting heavy-ion beams for inertial fusion. We postulate that the stability of these channels resides in the existance of a neutral-gas density depresion created by a pre-pulse discharge before the main capacitor bank discharge is created. Here, we present the results and experimental diagnostics setup used for the study of the pre-pulse and main bank channels. Observation of both the plasma and neutral gas dynamics is achieved. Schlieren, Zernike's phase-contrast, and spectroscopic techniques are used. Preliminary Schlieren results show a gas shockwave moving radially at a rate of ≈ 10^6 mm/sec as a result of the fast and localized deposited energy during the evolution of the pre-pulse channel. This data will be used to validate simulation codes (BUCKY and CYCLOPS).

A correlation electron cyclotron emission diagnostic and the importance of multifield fluctuation measurements for testing nonlinear gyrokinetic turbulence simulations.

PubMed

White, A E; Schmitz, L; Peebles, W A; Carter, T A; Rhodes, T L; Doyle, E J; Gourdain, P A; Hillesheim, J C; Wang, G; Holland, C; Tynan, G R; Austin, M E; McKee, G R; Shafer, M W; Burrell, K H; Candy, J; DeBoo, J C; Prater, R; Staebler, G M; Waltz, R E; Makowski, M A

2008-10-01

A correlation electron cyclotron emission (CECE) diagnostic has been used to measure local, turbulent fluctuations of the electron temperature in the core of DIII-D plasmas. This paper describes the hardware and testing of the CECE diagnostic and highlights the importance of measurements of multifield fluctuation profiles for the testing and validation of nonlinear gyrokinetic codes. The process of testing and validating such codes is critical for extrapolation to next-step fusion devices. For the first time, the radial profiles of electron temperature and density fluctuations are compared to nonlinear gyrokinetic simulations. The CECE diagnostic at DIII-D uses correlation radiometry to measure the rms amplitude and spectrum of the electron temperature fluctuations. Gaussian optics are used to produce a poloidal spot size with w(o) approximately 1.75 cm in the plasma. The intermediate frequency filters and the natural linewidth of the EC emission determine the radial resolution of the CECE diagnostic, which can be less than 1 cm. Wavenumbers resolved by the CECE diagnostic are k(theta) < or = 1.8 cm(-1) and k(r) < or = 4 cm(-1), relevant for studies of long-wavelength turbulence associated with the trapped electron mode and the ion temperature gradient mode. In neutral beam heated L-mode plasmas, core electron temperature fluctuations in the region 0.5 < r/a < 0.9, increase with radius from approximately 0.5% to approximately 2%, similar to density fluctuations that are measured simultaneously with beam emission spectroscopy. After incorporating "synthetic diagnostics" to effectively filter the code output, the simulations reproduce the characteristics of the turbulence and transport at one radial location r/a = 0.5, but not at a second location, r/a = 0.75. These results illustrate that measurements of the profiles of multiple fluctuating fields can provide a significant constraint on the turbulence models employed by the code.

X-ray lines as a density diagnostic in DT plasmas near 100x solid density

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

Bailey, D.S.

1977-10-19

The use of electron impact broadened resonance lines to diagnose near-term high density diagnostics is discussed. In particular, the question of how to choose seed and pusher materials to have discernible broadening effects while maintaining line visibility is discussed.

A micro-scale plasma spectrometer for space and plasma edge applications (invited)

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

Scime, E. E., E-mail: escime@wvu.edu; Keesee, A. M.; Elliott, D.

2016-11-15

A plasma spectrometer design based on advances in lithography and microchip stacking technologies is described. A series of curved plate energy analyzers, with an integrated collimator, is etched into a silicon wafer. Tests of spectrometer elements, the energy analyzer and collimator, were performed with a 5 keV electron beam. The measured collimator transmission and energy selectivity were in good agreement with design targets. A single wafer element could be used as a plasma processing or fusion first wall diagnostic.

Particle-in-cell modeling of laser Thomson scattering in low-density plasmas at elevated laser intensities

NASA Astrophysics Data System (ADS)

Powis, Andrew T.; Shneider, Mikhail N.

2018-05-01

Incoherent Thomson scattering is a non-intrusive technique commonly used for measuring local plasma density. Within low-density, low-temperature plasmas and for sufficient laser intensity, the laser may perturb the local electron density via the ponderomotive force, causing the diagnostic to become intrusive and leading to erroneous results. A theoretical model for this effect is validated numerically via kinetic simulations of a quasi-neutral plasma using the particle-in-cell technique.

Preheating study by reflectivity measurements in laser-driven shocks

NASA Astrophysics Data System (ADS)

Benuzzi, A.; Koenig, M.; Faral, B.; Krishnan, J.; Pisani, F.; Batani, D.; Bossi, S.; Beretta, D.; Hall, T.; Ellwi, S.; Hüller, S.; Honrubia, J.; Grandjouan, N.

1998-06-01

A study on preheating effects in laser-driven shock waves is presented. Two different diagnostics were used: the color temperature measurement deduced by recording the target rear side emissivity in two spectral bands, and the rear surface reflectivity measurement by using a probe beam. In order to test the response of the two diagnostics to the preheating, three types of targets characterized by different radiative properties were used. The greater sensitivity of the second diagnostic compared with the first was demonstrated. A model which calculates the reflectivity using a one-dimensional hydrodynamic code data was developed. In this model, the wave propagation equations in the expanding plasma using an appropriate model for the electron-ion collision frequency applicable to the cold solid-hot plasma transition were solved. The comparison between the calculated and measured reflectivities allows us to estimate the preheating process.

Gaseous electron multiplier-based soft x-ray plasma diagnostics development: Preliminary tests at ASDEX Upgrade

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

Chernyshova, M., E-mail: maryna.chernyshova@ipplm.pl; Malinowski, K.; Czarski, T.

2016-11-15

A Gaseous Electron Multiplier (GEM)-based detector is being developed for soft X-ray diagnostics on tokamaks. Its main goal is to facilitate transport studies of impurities like tungsten. Such studies are very relevant to ITER, where the excessive accumulation of impurities in the plasma core should be avoided. This contribution provides details of the preliminary tests at ASDEX Upgrade (AUG) with a focus on the most important aspects for detector operation in harsh radiation environment. It was shown that both spatially and spectrally resolved data could be collected, in a reasonable agreement with other AUG diagnostics. Contributions to the GEM signalmore » include also hard X-rays, gammas, and neutrons. First simulations of the effect of high-energy photons have helped understanding these contributions.« less

Diagnostics for a waste processing plasma arc furnace (invited) (abstract)a)

NASA Astrophysics Data System (ADS)

Woskov, P. P.

1995-01-01

Maintaining the quality of our environment has become an important goal of society. As part of this goal new technologies are being sought to clean up hazardous waste sites and to treat ongoing waste streams. A 1 MW pilot scale dc graphite electrode plasma arc furnace (Mark II) has been constructed at MIT under a joint program among Pacific Northwest Laboratory (PNL), MIT, and Electro-Pyrolysis, Inc. (EPI)c) for the remediation of buried wastes in the DOE complex. A key part of this program is the development of new and improved diagnostics to study, monitor, and control the entire waste remediation process for the optimization of this technology and to safeguard the environment. Continuous, real time diagnostics are needed for a variety of the waste process parameters. These parameters include internal furnace temperatures, slag fill levels, trace metals content in the off-gas stream, off-gas molecular content, feed and slag characterization, and off-gas particulate size, density, and velocity distributions. Diagnostics are currently being tested at MIT for the first three parameters. An active millimeter-wave radiometer with a novel, rotatable graphite waveguide/mirror antenna system has been implemented on Mark II for the measurement of surface emission and emissivity which can be used to determine internal furnace temperatures and fill levels. A microwave torch plasma is being evaluated for use as a excitation source in the furnace off-gas stream for continuous atomic emission spectroscopy of trace metals. These diagnostics should find applicability not only to waste remediation, but also to other high temperature processes such as incinerators, power plants, and steel plants.

Diagnostic and prognostic values of serum exosomal microRNA-21 in children with hepatoblastoma: a Chinese population-based study.

PubMed

Liu, Wanbo; Chen, Sheng; Liu, Bing

2016-11-01

Hepatoblastoma (HB) is the most common primary malignant tumor of the liver in young children. The aim of this study is to identify the diagnostic and prognostic values of serum exosomal miR-21 in Chinese patients with HB. We retrospectively reviewed 32 children with HB. The expressions of miR-21 were detected by real-time PCR. The comparison of diagnostic performance of plasmatic, exosomal miR-21 and AFP levels was measured using the Area Under ROC Curve. For patients in HB group, miR-21 concentration was significantly higher in the exosomes compared with the exosome-depleted supernatants and whole plasma. Expression of miR-21 was significantly higher in patients with HB compared with control group in both plasma and exosomes. With respect to the diagnosis of patients with HB, exosomal miR-21 was significantly more accurate compared with the Alpha-fetoprotein levels. Moreover, exosomal miR-21 was an independent predictor of Even-free survival for patients with HB. In this study, we found that expression of miR-21 was significantly higher in patients with HB compared with control group in both plasma and exosomes, and we confirmed that exosomal miR-21 could be defined as a diagnostic and prognostic biomarker for patients with HB.

First experiment on LMJ facility: pointing and synchronisation qualification, sequences qualification

NASA Astrophysics Data System (ADS)

Henry, Olivier; Bretheau, Dominique; Luttmann, Michel; Graillot, Herve; Ferri, Michel; Seguineau, Frederic; Bar, Emmanuel; Patissou, Loic; Canal, Phillipe; Sautarel, Françoise; Tranquille Marques, Yves; Raffestin, Didier

2016-10-01

The LMJ (Laser mega Joule) facility at the CESTA site (Aquitaine, France) is a tool designed to deliver up to 1.2 MJ at 351 nm for plasma experiments. The experiment system will include 11 diagnostics: UV and X energy balances, imagers (Streak and stripe camera, CCD), spectrometers, and a Visar/pyrometer. The facility must be able to deliver, within the hour following the shot, all the results of the plasma diagnostics, alignment images and laser diagnostic measurements. These results have to be guaranteed in terms of conformity to the request and quality of measurement. The end of 2014 was devoted to the qualification of system pointing on target and synchronization within and between beams. The shots made with one chain (divided in 2 quads - 8 laser beams) have achieved 50 µm of misalignment accuracy (chain and quad channel) and a synchronization accuracy in the order of 50 ps. The performances achieved for plasma diagnostic (in the order of less 100 µm of alignment and timing accuracy less than 150 ps) comply with expectations. At the same time the first automatic sequences were tested. They allowed a shot on target every 6h:30 and in some case twice a day by reducing preparation actions, leading to a sequence of 4h:00. These shooting sequences are managed by an operating team of 7 people helped by 3 people for security aspects.

Electron density measurements for plasma adaptive optics

NASA Astrophysics Data System (ADS)

Neiswander, Brian W.

Over the past 40 years, there has been growing interest in both laser communications and directed energy weapons that operate from moving aircraft. As a laser beam propagates from an aircraft in flight, it passes through boundary layers, turbulence, and shear layers in the near-region of the aircraft. These fluid instabilities cause strong density gradients which adversely affect the transmission of laser energy to a target. Adaptive optics provides corrective measures for this problem but current technology cannot respond quickly enough to be useful for high speed flight conditions. This research investigated the use of plasma as a medium for adaptive optics for aero-optics applications. When a laser beam passes through plasma, its phase is shifted proportionally to the electron density and gas heating within the plasma. As a result, plasma can be utilized as a dynamically controllable optical medium. Experiments were carried out using a cylindrical dielectric barrier discharge plasma chamber which generated a sub-atmospheric pressure, low-temperature plasma. An electrostatic model of this design was developed and revealed an important design constraint relating to the geometry of the chamber. Optical diagnostic techniques were used to characterize the plasma discharge. Single-wavelength interferometric experiments were performed and demonstrated up to 1.5 microns of optical path difference (OPD) in a 633 nm laser beam. Dual-wavelength interferometry was used to obtain time-resolved profiles of the plasma electron density and gas heating inside the plasma chamber. Furthermore, a new multi-wavelength infrared diagnostic technique was developed and proof-of-concept simulations were conducted to demonstrate the system's capabilities.

FLOCK cluster analysis of plasma cell flow cytometry data predicts bone marrow involvement by plasma cell neoplasia.

PubMed

Dorfman, David M; LaPlante, Charlotte D; Li, Betty

2016-09-01

We analyzed plasma cell populations in bone marrow samples from 353 patients with possible bone marrow involvement by a plasma cell neoplasm, using FLOCK (FLOw Clustering without K), an unbiased, automated, computational approach to identify cell subsets in multidimensional flow cytometry data. FLOCK identified discrete plasma cell populations in the majority of bone marrow specimens found by standard histologic and immunophenotypic criteria to be involved by a plasma cell neoplasm (202/208 cases; 97%), including 34 cases that were negative by standard flow cytometric analysis that included clonality assessment. FLOCK identified discrete plasma cell populations in only a minority of cases negative for involvement by a plasma cell neoplasm by standard histologic and immunophenotypic criteria (38/145 cases; 26%). Interestingly, 55% of the cases negative by standard analysis, but containing a FLOCK-identified discrete plasma cell population, were positive for monoclonal gammopathy by serum protein electrophoresis and immunofixation. FLOCK-identified and quantitated plasma cell populations accounted for 3.05% of total cells on average in cases positive for involvement by a plasma cell neoplasm by standard histologic and immunophenotypic criteria, and 0.27% of total cells on average in cases negative for involvement by a plasma cell neoplasm by standard histologic and immunophenotypic criteria (p<0.0001; area under the curve by ROC analysis=0.96). The presence of a FLOCK-identified discrete plasma cell population was predictive of the presence of plasma cell neoplasia with a sensitivity of 97%, compared with only 81% for standard flow cytometric analysis, and had specificity of 74%, PPV of 84% and NPV of 95%. FLOCK analysis, which has been shown to provide useful diagnostic information for evaluating patients with suspected systemic mastocytosis, is able to identify neoplastic plasma cell populations analyzed by flow cytometry, and may be helpful in the diagnostic evaluation of bone marrow samples for involvement by plasma cell neoplasia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electron Temperature Fluctuation Measurements and Transport Model Validation at Alcator C-Mod

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

White, Anne

The tokamak is a type of toroidal device used to confine a fusion plasma using large magnetic fields. Tokamaks and stellarators the leading devices for confining plasmas for fusion, and the capability to predict performance in these magnetically confined plasmas is essential for developing a sustainable fusion energy source. The magnetic configuration of tokamaks and stellarators does not exist in Nature, yet, the fundamental processes governing transport in fusion plasmas are universal – turbulence and instabilities, driven by inhomogeneity and asymmetry in the plasma, conspire to transport heat and particles across magnetic field lines and can play critical roles inmore » impurity confinement and generation of intrinsic rotation. Turbulence exists in all plasmas, and in neutral fluids as well. The study of turbulence is essential to developing a fundamental understanding of the nature of the fourth state of matter, plasmas. Experimental studies of turbulence in tokamaks date back to early scattering observations from the late 1970s. Since that time, great advances in turbulence diagnostics have been made, all of which have significantly enhanced our knowledge and understanding of turbulence in tokamaks. Through comparisons with advanced gyrokinetic theory and turbulent-transport models a great deal of evidence exists to implicate turbulent-driven transport as an important mechanism determining transport in all channels: heat, particle and momentum However, prediction and control of turbulent-driven transport remains elusive. Key to development of predictive transport models for magnetically confined fusion plasmas is validation of the nonlinear gyrokinetic transport model, which describes transport due to turbulence. Validation of gyrokinetic codes must include detailed and quantitative comparisons with measured turbulence characteristics, in addition to comparisons with inferred transport levels and equilibrium profiles. For this reason, advanced plasma diagnostics for studying core turbulence are needed in order to assess the accuracy of gyrokinetic models for turbulent-driven particle, heat and momentum transport. New core turbulence diagnostics at the world-class tokamaks Alcator C-Mod at MIT and ASDEX Upgrade at the Max Planck Institute for Plasma Physics have been designed, developed, and operated over the course of this project. These new instruments are capable of measuring electron temperature fluctuations and the phase angle between density and temperature fluctuations locally and quantitatively. These new data sets from Alcator C-Mod and ASDEX Upgrade are being used to fill key gaps in our understanding of turbulent transport in tokamaks. In particular, this project has results in new results on the topics of the Transport Shortfall, the role of ETG turbulence in tokamak plasmas, profile stiffness, the LOC/SOC transition, and intrinsic rotation reversals. These data are used in a rigorous process of “Transport model validation”, and this group is a world-leader on using turbulence models to design new hardware and new experiments at tokamaks. A correlation electron cyclotron emission (CECE) diagnostic is an instrument used to measure micro-scale fluctuations (mm-scale, compared to the machine size of meters) of electron temperature in magnetically confined fusion plasmas, such as those in tokamaks and stellarators. These micro-scale fluctuations are associated with drift-wave type turbulence, which leads to enhanced cooling and mixing of particles in fusion plasmas and limits achieving the required temperatures and densities for self-sustained fusion reactions. A CECE system can also be coupled with a reflectometer system that measured micro-scale density fluctuations, and from these simultaneous measurements, one can extract the phase between the density (n) and temperature (T) fluctuations, creating an nT phase diagnostic. Measurements of the fluctuations and the phase angle between them are extremely useful for testing and validating predictive models for the transport of heat and particles in fusion plasmas due to turbulence. Once validated, the models are used to predict performance in ITER and other burning plasmas, such as the MIT ARC design. Most recently, data from the newly developed, so-called “CECE diagnostic” [Cima 1995, White 2008] and “nT phase angle measurements” [Haese 1999, White 2010] ]will be combined with data from density fluctuation diagnostics at ASDEX Upgrade to support a long-term program of physics research in turbulence and transport that will allow for more stringent testing and validation of gyrokinetic turbulent-transport codes. This work directly impacts the development of predictive transport models in the U.S. FES program, such as TGLF, developed by General Atomics, which are used to predict performance in ITER and other burning plasma devices as part of advancing the development of fusion energy sciences.« less

PLASMA DIAGNOSTICS OF AN EIT WAVE OBSERVED BY HINODE/EIS AND SDO/AIA

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

Veronig, A. M.; Kienreich, I. W.; Muhr, N.

2011-12-10

We present plasma diagnostics of an Extreme-Ultraviolet Imaging Telescope (EIT) wave observed with high cadence in Hinode/Extreme-Ultraviolet Imaging Spectrometer (EIS) sit-and-stare spectroscopy and Solar Dynamics Observatory/Atmospheric Imaging Assembly imagery obtained during the HOP-180 observing campaign on 2011 February 16. At the propagating EIT wave front, we observe downward plasma flows in the EIS Fe XII, Fe XIII, and Fe XVI spectral lines (log T Almost-Equal-To 6.1-6.4) with line-of-sight (LOS) velocities up to 20 km s{sup -1}. These redshifts are followed by blueshifts with upward velocities up to -5 km s{sup -1} indicating relaxation of the plasma behind the wave front.more » During the wave evolution, the downward velocity pulse steepens from a few km s{sup -1} up to 20 km s{sup -1} and subsequently decays, correlated with the relative changes of the line intensities. The expected increase of the plasma densities at the EIT wave front estimated from the observed intensity increase lies within the noise level of our density diagnostics from EIS Fe XIII 202/203 A line ratios. No significant LOS plasma motions are observed in the He II line, suggesting that the wave pulse was not strong enough to perturb the underlying chromosphere. This is consistent with the finding that no H{alpha} Moreton wave was associated with the event. The EIT wave propagating along the EIS slit reveals a strong deceleration of a Almost-Equal-To -540 m s{sup -2} and a start velocity of v{sub 0} Almost-Equal-To 590 km s{sup -1}. These findings are consistent with the passage of a coronal fast-mode MHD wave, pushing the plasma downward and compressing it at the coronal base.« less

Automatization of hardware configuration for plasma diagnostic system

NASA Astrophysics Data System (ADS)

Wojenski, A.; Pozniak, K. T.; Kasprowicz, G.; Kolasinski, P.; Krawczyk, R. D.; Zabolotny, W.; Linczuk, P.; Chernyshova, M.; Czarski, T.; Malinowski, K.

2016-09-01

Soft X-ray plasma measurement systems are mostly multi-channel, high performance systems. In case of the modular construction it is necessary to perform sophisticated system discovery in parallel with automatic system configuration. In the paper the structure of the modular system designed for tokamak plasma soft X-ray measurements is described. The concept of the system discovery and further automatic configuration is also presented. FCS application (FMC/ FPGA Configuration Software) is used for running sophisticated system setup with automatic verification of proper configuration. In order to provide flexibility of further system configurations (e.g. user setup), common communication interface is also described. The approach presented here is related to the automatic system firmware building presented in previous papers. Modular construction and multichannel measurements are key requirement in term of SXR diagnostics with use of GEM detectors.

The implementation and data analysis of an interferometer for intense short pulse laser experiments

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

Park, Jaebum; Baldis, Hector A.; Chen, Hui

We present an interferometry setup and the detailed fringe analysis method for intense short pulse (SP) laser experiments. The interferometry scheme was refined through multiple campaigns to investigate the effects of pre-plasmas on energetic electrons at the Jupiter Laser Facility at Lawrence Livermore National Laboratory. The interferometer used a frequency doubled (more » $${\\it\\lambda}=0.527~{\\rm\\mu}\\text{m}$$) 0.5 ps long optical probe beam to measure the pre-plasma density, an invaluable parameter to better understand how varying pre-plasma conditions affect the characteristics of the energetic electrons. The hardware of the diagnostic, data analysis and example data are presented. Here, the diagnostic setup and the analysis procedure can be employed for any other SP laser experiments and interferograms, respectively.« less

The implementation and data analysis of an interferometer for intense short pulse laser experiments

DOE PAGES

Park, Jaebum; Baldis, Hector A.; Chen, Hui

2016-08-03

We present an interferometry setup and the detailed fringe analysis method for intense short pulse (SP) laser experiments. The interferometry scheme was refined through multiple campaigns to investigate the effects of pre-plasmas on energetic electrons at the Jupiter Laser Facility at Lawrence Livermore National Laboratory. The interferometer used a frequency doubled (more » $${\\it\\lambda}=0.527~{\\rm\\mu}\\text{m}$$) 0.5 ps long optical probe beam to measure the pre-plasma density, an invaluable parameter to better understand how varying pre-plasma conditions affect the characteristics of the energetic electrons. The hardware of the diagnostic, data analysis and example data are presented. Here, the diagnostic setup and the analysis procedure can be employed for any other SP laser experiments and interferograms, respectively.« less

SXR measurement and W transport survey using GEM tomographic system on WEST

NASA Astrophysics Data System (ADS)

Mazon, D.; Jardin, A.; Malard, P.; Chernyshova, M.; Coston, C.; Malard, P.; O'Mullane, M.; Czarski, T.; Malinowski, K.; Faisse, F.; Ferlay, F.; Verger, J. M.; Bec, A.; Larroque, S.; Kasprowicz, G.; Wojenski, A.; Pozniak, K.

2017-11-01

Measuring Soft X-Ray (SXR) radiation (0.1-20 keV) of fusion plasmas is a standard way of accessing valuable information on particle transport. Since heavy impurities like tungsten (W) could degrade plasma core performances and cause radiative collapses, it is necessary to develop new diagnostics to be able to monitor the impurity distribution in harsh fusion environments like ITER. A gaseous detector with energy discrimination would be a very good candidate for this purpose. The design and implementation of a new SXR diagnostic developed for the WEST project, based on a triple Gas Electron Multiplier (GEM) detector is presented. This detector works in photon counting mode and presents energy discrimination capabilities. The SXR system is composed of two 1D cameras (vertical and horizontal views respectively), located in the same poloidal cross-section to allow for tomographic reconstruction. An array (20 cm × 2 cm) consists of up to 128 detectors in front of a beryllium pinhole (equipped with a 1 mm diameter diaphragm) inserted at about 50 cm depth inside a cooled thimble in order to retrieve a wide plasma view. Acquisition of low energy spectrum is insured by a helium buffer installed between the pinhole and the detector. Complementary cooling systems (water) are used to maintain a constant temperature (25oC) inside the thimble. Finally a real-time automatic extraction system has been developed to protect the diagnostic during baking phases or any overheating unwanted events. Preliminary simulations of plasma emissivity and W distribution have been performed for WEST using a recently developed synthetic diagnostic coupled to a tomographic algorithm based on the minimum Fisher information (MFI) inversion method. First GEM acquisitions are presented as well as estimation of transport effect in presence of ICRH on W density reconstruction capabilities of the GEM.

Intermediate frequency band digitized high dynamic range radiometer system for plasma diagnostics and real-time Tokamak control

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

Bongers, W. A.; Beveren, V. van; Westerhof, E.

2011-06-15

An intermediate frequency (IF) band digitizing radiometer system in the 100-200 GHz frequency range has been developed for Tokamak diagnostics and control, and other fields of research which require a high flexibility in frequency resolution combined with a large bandwidth and the retrieval of the full wave information of the mm-wave signals under investigation. The system is based on directly digitizing the IF band after down conversion. The enabling technology consists of a fast multi-giga sample analog to digital converter that has recently become available. Field programmable gate arrays (FPGA) are implemented to accomplish versatile real-time data analysis. A prototypemore » system has been developed and tested and its performance has been compared with conventional electron cyclotron emission (ECE) spectrometer systems. On the TEXTOR Tokamak a proof of principle shows that ECE, together with high power injected and scattered radiation, becomes amenable to measurement by this device. In particular, its capability to measure the phase of coherent signals in the spectrum offers important advantages in diagnostics and control. One case developed in detail employs the FPGA in real-time fast Fourier transform (FFT) and additional signal processing. The major benefit of such a FFT-based system is the real-time trade-off that can be made between frequency and time resolution. For ECE diagnostics this corresponds to a flexible spatial resolution in the plasma, with potential application in smart sensing of plasma instabilities such as the neoclassical tearing mode (NTM) and sawtooth instabilities. The flexible resolution would allow for the measurement of the full mode content of plasma instabilities contained within the system bandwidth.« less

Spatial Expansion and Automation of the Pegasus Thomson Scattering Diagnostic System

NASA Astrophysics Data System (ADS)

Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Reusch, J. A.; Schlossberg, D. J.; Winz, G. R.

2015-11-01

The Pegasus Thomson scattering diagnostic system has recently undergone modifications to increase the spatial range of the diagnostic and automate the Thomson data collection process. Two multichannel spectrometers have been added to the original configuration, providing a total of 24 data channels to view the plasma volume. The new system configuration allows for observation of three distinct regions of the plasma: the local helicity injection (LHI) source (R ~ 67-73.8 cm), the plasma edge (R ~ 51.5-57.6 cm), and the plasma core (R ~ 35-41.1 cm). Each spectrometer utilizes a volume-phase holographic (VPH) grating and a gated-intensified CCD camera. The edge and the LHI spectrometers have been fitted with low-temperature VPH gratings to cover Te = 10 - 100 eV, while the core spectrometer has been fitted with a high-temperature VPH grating to cover Te = 0 . 1 - 1 . 0 keV. The additional spectrometers have been calibrated to account for detector flatness, detector linearity, and vignetting. Operation of the Thomson system has been overhauled to utilize LabVIEW software to synchronize the major components of the Thomson system with the Pegasus shot cycle and to provide intra-shot beam alignment. Multi-point Thomson scattering measurements will be obtained in the aforementioned regions of LHI and Ohmic discharges and will be compared to Langmuir probe measurements. Work supported by US DOE grant DE-FG02-96ER54375.

Secretion of pancreatic polypeptide in patients with pancreatic endocrine tumors.

PubMed

Adrian, T E; Uttenthal, L O; Williams, S J; Bloom, S R

1986-07-31

Pancreatic polypeptide is often secreted by pancreatic endocrine tumors and is considered a marker for such tumors. To investigate the diagnostic value of this marker, we studied 323 patients with proved pancreatic endocrine tumors. We found plasma concentrations of pancreatic polypeptide to be elevated (more than 300 pmol per liter) in 144 patients (diagnostic sensitivity, 45 percent). However, plasma levels of pancreatic polypeptide can also be elevated in the absence of a pancreatic tumor. To ascertain whether the administration of atropine could distinguish between normal and tumor-associated polypeptide secretion, we studied 30 patients with pancreatic tumors and high plasma levels of pancreatic polypeptide, 18 patients without tumors who had elevated levels of pancreatic polypeptide, and eight normal controls. Polypeptide levels in the 18 patients without tumors were substantially lower than in the 30 patients with tumors. Atropine (1 mg intramuscularly) did not suppress polypeptide levels in patients with tumors, but did suppress plasma levels by more than 50 percent in all subjects without tumors. Thus, although its diagnostic sensitivity is low, pancreatic polypeptide appears to be a useful adjunctive marker of many pancreatic endocrine tumors, and the atropine suppression test can be used to distinguish normal from tumor-related secretion of the polypeptide. Identification of the type of pancreatic endocrine tumor still requires measurement of the hormone that is specific for the tumor.

Dust measurements in tokamaks (invited).

PubMed

Rudakov, D L; Yu, J H; Boedo, J A; Hollmann, E M; Krasheninnikov, S I; Moyer, R A; Muller, S H; Pigarov, A Yu; Rosenberg, M; Smirnov, R D; West, W P; Boivin, R L; Bray, B D; Brooks, N H; Hyatt, A W; Wong, C P C; Roquemore, A L; Skinner, C H; Solomon, W M; Ratynskaia, S; Fenstermacher, M E; Groth, M; Lasnier, C J; McLean, A G; Stangeby, P C

2008-10-01

Dust production and accumulation present potential safety and operational issues for the ITER. Dust diagnostics can be divided into two groups: diagnostics of dust on surfaces and diagnostics of dust in plasma. Diagnostics from both groups are employed in contemporary tokamaks; new diagnostics suitable for ITER are also being developed and tested. Dust accumulation in ITER is likely to occur in hidden areas, e.g., between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In the DIII-D tokamak dust diagnostics include Mie scattering from Nd:YAG lasers, visible imaging, and spectroscopy. Laser scattering is able to resolve particles between 0.16 and 1.6 microm in diameter; using these data the total dust content in the edge plasmas and trends in the dust production rates within this size range have been established. Individual dust particles are observed by visible imaging using fast framing cameras, detecting dust particles of a few microns in diameter and larger. Dust velocities and trajectories can be determined in two-dimension with a single camera or three-dimension using multiple cameras, but determination of particle size is challenging. In order to calibrate diagnostics and benchmark dust dynamics modeling, precharacterized carbon dust has been injected into the lower divertor of DIII-D. Injected dust is seen by cameras, and spectroscopic diagnostics observe an increase in carbon line (CI, CII, C(2) dimer) and thermal continuum emissions from the injected dust. The latter observation can be used in the design of novel dust survey diagnostics.

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

Rudakov, D. L.; Yu, J. H.; Boedo, J. A.

Dust production and accumulation present potential safety and operational issues for the ITER. Dust diagnostics can be divided into two groups: diagnostics of dust on surfaces and diagnostics of dust in plasma. Diagnostics from both groups are employed in contemporary tokamaks; new diagnostics suitable for ITER are also being developed and tested. Dust accumulation in ITER is likely to occur in hidden areas, e.g., between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In the DIII-D tokamak dust diagnostics include Mie scattering from Nd:YAG lasers,more » visible imaging, and spectroscopy. Laser scattering is able to resolve particles between 0.16 and 1.6 {mu}m in diameter; using these data the total dust content in the edge plasmas and trends in the dust production rates within this size range have been established. Individual dust particles are observed by visible imaging using fast framing cameras, detecting dust particles of a few microns in diameter and larger. Dust velocities and trajectories can be determined in two-dimension with a single camera or three-dimension using multiple cameras, but determination of particle size is challenging. In order to calibrate diagnostics and benchmark dust dynamics modeling, precharacterized carbon dust has been injected into the lower divertor of DIII-D. Injected dust is seen by cameras, and spectroscopic diagnostics observe an increase in carbon line (CI, CII, C{sub 2} dimer) and thermal continuum emissions from the injected dust. The latter observation can be used in the design of novel dust survey diagnostics.« less

An energy confinement study of the MST (Madison Symmetric Torus) reversed field pinch using a Thomson scattering diagnostic

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

Den Hartog, D.J.

1989-11-01

Thomson scattering measurements of the central electron temperature and density during the plasma current peak have been performed on the MST Reversed Field Pinch (RFP). This Thomson scattering diagnostic was calibrated for absolute electron density measurements. These measurements of T{sub e} and n{sub e}, when combined with profile assumptions, were used to calculate estimates of energy confinement time ({tau}{sub E}) and poloidal beta ({beta}{sub {theta}}). A standard discharge with I{sub p} {approx} 400 kA, F {approx} {minus}0.1, and {theta} {approx} 1.6 typically exhibited T{sub e} {approx} 275 eV, n{sub e} {approx} 2.0 {times} 10{sup 13} cm{sup {minus}3}, {tau}{sub E} {le}more » 1 ms, and {beta}{sub {theta}} {le} 8%. The results of a limited plasma current scaling study did not indicate a strong scaling of T{sub e} or {tau}{sub E} with I{sub p}. The Thomson scattering diagnostic was used in conjunction with a bolometer, VUV radiation monitor, and edge magnetic coils to study the loss of energy from the plasma. Results indicate that thermal transport from stochastic magnetic fields, particle loss, and radiation are important energy loss processes. The experiments done for this study included an F-scan, a paddle limiter insertion series, and an argon doping series. The plasma maintained a constant {beta}{tau} during these perturbation experiments, suggesting that increases in one energy loss channel are compensated by drops in other channels and increases in input power to the plasma.« less

An energy-confinement study of the MST reversed-field pinch using a Thomson-scattering diagnostic

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

Den Hartog, D.J.

1989-01-01

Thomson scattering measurements of the central electron temperature and density during the plasma current peak have been performed on the MST Reversed Field Pinch (RFP). This Thomson scattering diagnostic was calibrated for absolute electron density measurements. These measurements of T{sub e} and n{sub e}, when combined with profile assumptions, were used to calculate estimates of energy confinement time ({tau}{sub E}) and poloidal beta ({beta}{sub {theta}}). A standard discharge with I{sub p} {approx} 400 kA, F {approx} {minus}0.1, and {theta} {approx} 1.6 typically exhibited T{sub e} {approx} 275 eV, n{sub e} {approx} 2.0 {times} 10{sup 13} cm{sup {minus}3}, {tau}{sub E}

Parametric Thermal and Flow Analysis of ITER Diagnostic Shield Module

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

Khodak, A.; Zhai, Y.; Wang, W.

As part of the diagnostic port plug assembly, the ITER Diagnostic Shield Module (DSM) is designed to provide mechanical support and the plasma shielding while allowing access to plasma diagnostics. Thermal and hydraulic analysis of the DSM was performed using a conjugate heat transfer approach, in which heat transfer was resolved in both solid and liquid parts, and simultaneously, fluid dynamics analysis was performed only in the liquid part. ITER Diagnostic First Wall (DFW) and cooling tubing were also included in the analysis. This allowed direct modeling of the interface between DSM and DFW, and also direct assessment of themore » coolant flow distribution between the parts of DSM and DFW to ensure DSM design meets the DFW cooling requirements. Design of the DSM included voids filled with Boron Carbide pellets, allowing weight reduction while keeping shielding capability of the DSM. These voids were modeled as a continuous solid with smeared material properties using analytical relation for thermal conductivity. Results of the analysis lead to design modifications improving heat transfer efficiency of the DSM. Furthermore, the effect of design modifications on thermal performance as well as effect of Boron Carbide will be presented.« less

ITER ECE Diagnostic: Design Progress of IN-DA and the diagnostic role for Physics

NASA Astrophysics Data System (ADS)

Pandya, H. K. B.; Kumar, Ravinder; Danani, S.; Shrishail, P.; Thomas, Sajal; Kumar, Vinay; Taylor, G.; Khodak, A.; Rowan, W. L.; Houshmandyar, S.; Udintsev, V. S.; Casal, N.; Walsh, M. J.

2017-04-01

The ECE Diagnostic system in ITER will be used for measuring the electron temperature profile evolution, electron temperature fluctuations, the runaway electron spectrum, and the radiated power in the electron cyclotron frequency range (70-1000 GHz), These measurements will be used for advanced real time plasma control (e.g. steering the electron cyclotron heating beams), and physics studies. The scope of the Indian Domestic Agency (IN-DA) is to design and develop the polarizer splitter units; the broadband (70 to 1000 GHz) transmission lines; a high temperature calibration source in the Diagnostics Hall; two Michelson Interferometers (70 to 1000 GHz) and a 122-230 GHz radiometer. The remainder of the ITER ECE diagnostic system is the responsibility of the US domestic agency and the ITER Organization (IO). The design needs to conform to the ITER Organization’s strict requirements for reliability, availability, maintainability and inspect-ability. Progress in the design and development of various subsystems and components considering various engineering challenges and solutions will be discussed in this paper. This paper will also highlight how various ECE measurements can enhance understanding of plasma physics in ITER.

Parametric Thermal and Flow Analysis of ITER Diagnostic Shield Module

DOE PAGES

Khodak, A.; Zhai, Y.; Wang, W.; ...

2017-06-19

As part of the diagnostic port plug assembly, the ITER Diagnostic Shield Module (DSM) is designed to provide mechanical support and the plasma shielding while allowing access to plasma diagnostics. Thermal and hydraulic analysis of the DSM was performed using a conjugate heat transfer approach, in which heat transfer was resolved in both solid and liquid parts, and simultaneously, fluid dynamics analysis was performed only in the liquid part. ITER Diagnostic First Wall (DFW) and cooling tubing were also included in the analysis. This allowed direct modeling of the interface between DSM and DFW, and also direct assessment of themore » coolant flow distribution between the parts of DSM and DFW to ensure DSM design meets the DFW cooling requirements. Design of the DSM included voids filled with Boron Carbide pellets, allowing weight reduction while keeping shielding capability of the DSM. These voids were modeled as a continuous solid with smeared material properties using analytical relation for thermal conductivity. Results of the analysis lead to design modifications improving heat transfer efficiency of the DSM. Furthermore, the effect of design modifications on thermal performance as well as effect of Boron Carbide will be presented.« less

Plasma detachment in divertor tokamaks

NASA Astrophysics Data System (ADS)

Leonard, A. W.

2018-04-01

Observations of divertor plasma detachment in tokamaks are reviewed. Plasma detachment is characterized in terms of transport and dissipation of power, momentum and particle flux along the open field lines from the midplane to the divertor. Asymmetries in detachment onset and other characteristics between the inboard and outboard divertor plasmas is found to be primarily driven by plasma E× B drifts. The effect of divertor plate geometry and magnetic configuration on divertor detachment is summarized. Control of divertor detachment has progressed with a development of a number of diagnostics to characterize the detached state in real-time. Finally the compatibility of detached divertor operation with high performance core plasmas is examined.

A technique for plasma velocity-space cross-correlation

NASA Astrophysics Data System (ADS)

Mattingly, Sean; Skiff, Fred

2018-05-01

An advance in experimental plasma diagnostics is presented and used to make the first measurement of a plasma velocity-space cross-correlation matrix. The velocity space correlation function can detect collective fluctuations of plasmas through a localized measurement. An empirical decomposition, singular value decomposition, is applied to this Hermitian matrix in order to obtain the plasma fluctuation eigenmode structure on the ion distribution function. A basic theory is introduced and compared to the modes obtained by the experiment. A full characterization of these modes is left for future work, but an outline of this endeavor is provided. Finally, the requirements for this experimental technique in other plasma regimes are discussed.

Plasma density characterization at SPARC_LAB through Stark broadening of Hydrogen spectral lines

NASA Astrophysics Data System (ADS)

Filippi, F.; Anania, M. P.; Bellaveglia, M.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Di Giovenale, D.; Di Pirro, G.; Ferrario, M.; Mostacci, A.; Palumbo, L.; Pompili, R.; Shpakov, V.; Vaccarezza, C.; Villa, F.; Zigler, A.

2016-09-01

Plasma-based acceleration techniques are of great interest for future, compact accelerators due to their high accelerating gradient. Both particle-driven and laser-driven Plasma Wakefield Acceleration experiments are foreseen at the SPARC_LAB Test Facility (INFN National Laboratories of Frascati, Italy), with the aim to accelerate high-brightness electron beams. In order to optimize the efficiency of the acceleration in the plasma and preserve the quality of the accelerated beam, the knowledge of the plasma electron density is mandatory. The Stark broadening of the Hydrogen spectral lines is one of the candidates used to characterize plasma density. The implementation of this diagnostic for plasma-based experiments at SPARC_LAB is presented.

Overview Experimental Diagnostics for Rarefied Flows - Selected Topics

DTIC Science & Technology

2011-01-01

flows occurring e.g. in electrical thrusters or plasma wind tunnels. Classical intrusive techniques like Pitot, heat flux, and enthalpy probe as well as...and applied at the IRS, especially designed for the characterisation of flows produced by electrical thrusters and within the plasma wind tunnels for...occurring e.g. in electrical thrusters or plasma wind tunnels. Classical intrusive techniques like Pitot, heat flux, and enthalpy probe as well as mass

Development of a GPU-Accelerated 3-D Full-Wave Code for Electromagnetic Wave Propagation in a Cold Plasma

NASA Astrophysics Data System (ADS)

Woodbury, D.; Kubota, S.; Johnson, I.

2014-10-01

Computer simulations of electromagnetic wave propagation in magnetized plasmas are an important tool for both plasma heating and diagnostics. For active millimeter-wave and microwave diagnostics, accurately modeling the evolution of the beam parameters for launched, reflected or scattered waves in a toroidal plasma requires that calculations be done using the full 3-D geometry. Previously, we reported on the application of GPGPU (General-Purpose computing on Graphics Processing Units) to a 3-D vacuum Maxwell code using the FDTD (Finite-Difference Time-Domain) method. Tests were done for Gaussian beam propagation with a hard source antenna, utilizing the parallel processing capabilities of the NVIDIA K20M. In the current study, we have modified the 3-D code to include a soft source antenna and an induced current density based on the cold plasma approximation. Results from Gaussian beam propagation in an inhomogeneous anisotropic plasma, along with comparisons to ray- and beam-tracing calculations will be presented. Additional enhancements, such as advanced coding techniques for improved speedup, will also be investigated. Supported by U.S. DoE Grant DE-FG02-99-ER54527 and in part by the U.S. DoE, Office of Science, WDTS under the Science Undergraduate Laboratory Internship program.

Extreme ultraviolet and Soft X-ray diagnostic upgrade on the HBT-EP tokamak: Progress and Results

NASA Astrophysics Data System (ADS)

Desanto, S.; Levesque, J. P.; Battey, A.; Brooks, J. W.; Mauel, M. E.; Navratil, G. A.; Hansen, C. J.

2017-10-01

In order to understand internal MHD mode structure in a tokamak plasma, it is helpful to understand temperature and density fluctuations within that plasma. In the HBT-EP tokamak, the plasma emits bremsstrahlung radiation in the extreme ultraviolet (EUV) and soft x-ray (SXR) regimes, and the emitted power is primarily related to electron density and temperature. This radiation is detected by photodiode arrays located at several different angular positions near the plasma's edge, each array making several views through a poloidal slice of plasma. From these measurements a 2-d emissivity profile of that slice can be reconstructed with tomographic algorithms. This profile cannot directly tell us whether the emissivity is due to electron density, temperature, line emission, or charge recombination; however, when combined with information from other diagnostics, it can provide strong evidence of the type of internal mode or modes depending on the temporal-spatial context. We present ongoing progress and results on the installation of a new system that will eventually consist of four arrays of 16 views each and a separate two-color, 16-chord tangential system, which will provide an improved understanding of the internal structure of HBT-EP plasmas. Supported by U.S. DOE Grant DE-FG02-86ER5322.

The behavior of neutron emissions during ICRF minority heating of plasma at EAST

NASA Astrophysics Data System (ADS)

Zhong, Guoqiang; Cao, Hongrui; Hu, Liqun; Zhou, Ruijie; Xiao, Min; Li, Kai; Pu, Neng; Huang, Juan; Liu, Guangzhu; Lin, Shiyao; Lyu, Bo; Liu, Haiqing; Zhang, Xinjun; EAST Team

2016-07-01

Ion cyclotron radio frequency (ICRF) wave heating is a primary method to heat ions in the Experimental Advanced Superconducting Tokamak (EAST). Through neutron diagnostics, effective ion heating was observed in hydrogenminority heating (MH) scenarios. At present, investigation of deuterium-deuterium (DD) fusion neutrons is mostly based on time-resolved flux monitor and spectrometer measurements. When the ICRF was applied, the neutron intensity became one order higher. The H/H  +  D ratio was in the range of 5-10%, corresponding to the hydrogen MH dominated scenario, and a strong high energy tail was not displayed on the neutron spectrum that was measured by a liquid scintillator. Moreover, ion temperature in the plasma center (T i) was inversely calculated by the use of neutron source strength (S n) and the plasma density based on classical fusion reaction equations. This result indicates that T i increases by approximately 30% in L-mode plasma, and by more than 50% in H-mode plasma during ICRF heating, which shows good agreement with x-ray crystal spectrometer (XCS) diagnostics. Finally, the DD neutron source strength scaling law, with regard to plasma current (I P) and ICRF coupling power (P RF) on the typical minority heating condition, was obtained by statistical analysis.

Diagnostic and prognostic value of plasma and tissue ubiquitin-like, containing PHD and RING finger domains 1 in breast cancer patients.

PubMed

Geng, Yao; Gao, Yanfang; Ju, Huangxian; Yan, Feng

2013-02-01

Ubiquitin-like, containing PHD and RING finger domains 1 (UHRF1) has been reported to play an important role in breast carcinogenesis. This work investigated the correlation of UHRF1 DNA level in plasma with clinical characteristics of breast cancer and its clinical significance in breast cancer diagnosis. The expression of UHRF1 in primary breast cancer tissue was examined by Western blot. The UHRF1 DNA levels in plasma and UHRF1 mRNA expression in tissues were determined by accurate real-time quantitative PCR. The associations of UHRF1 levels with clinical variables were evaluated using standard statistical methods. The UHRF1 DNA in plasma of 229 breast cancer patients showed higher expression than healthy controls, which showed high specificity up to 76.2% at a sensitivity of 79.2%, and was significantly associated with c-erbB2 positive status, cancer stage and lymph node metastasis. High UHRF1 DNA level in plasma was significantly associated with short progression-free survival. The UHRF1 DNA level in plasma is highly correlative with breast cancer and its status and stage, and may be a potential independent diagnostic and prognostic factor for both breast cancer and the survival of breast cancer patients. © 2012 Japanese Cancer Association.

Electromagnetic diagnostics of ECR-Ion Sources plasmas: optical/X-ray imaging and spectroscopy

NASA Astrophysics Data System (ADS)

Mascali, D.; Castro, G.; Altana, C.; Caliri, C.; Mazzaglia, M.; Romano, F. P.; Leone, F.; Musumarra, A.; Naselli, E.; Reitano, R.; Torrisi, G.; Celona, L.; Cosentino, L. G.; Giarrusso, M.; Gammino, S.

2017-12-01

Magnetoplasmas in ECR-Ion Sources are excited from gaseous elements or vapours by microwaves in the range 2.45-28 GHz via Electron Cyclotron Resonance. A B-minimum, magnetohydrodynamic stable configuration is used for trapping the plasma. The values of plasma density, temperature and confinement times are typically ne= 1011-1013 cm-3, 01 eV

Quantum cascade laser based monitoring of CF{sub 2} radical concentration as a diagnostic tool of dielectric etching plasma processes

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

Hübner, M.; Lang, N.; Röpcke, J.

2015-01-19

Dielectric etching plasma processes for modern interlevel dielectrics become more and more complex by the introduction of new ultra low-k dielectrics. One challenge is the minimization of sidewall damage, while etching ultra low-k porous SiCOH by fluorocarbon plasmas. The optimization of this process requires a deeper understanding of the concentration of the CF{sub 2} radical, which acts as precursor in the polymerization of the etch sample surfaces. In an industrial dielectric etching plasma reactor, the CF{sub 2} radical was measured in situ using a continuous wave quantum cascade laser (cw-QCL) around 1106.2 cm{sup −1}. We measured Doppler-resolved ro-vibrational absorption lines andmore » determined absolute densities using transitions in the ν{sub 3} fundamental band of CF{sub 2} with the aid of an improved simulation of the line strengths. We found that the CF{sub 2} radical concentration during the etching plasma process directly correlates to the layer structure of the etched wafer. Hence, this correlation can serve as a diagnostic tool of dielectric etching plasma processes. Applying QCL based absorption spectroscopy opens up the way for advanced process monitoring and etching controlling in semiconductor manufacturing.« less

Development of Laser Based Plasma Diagnostics for Fusion Research on NSTX-U

NASA Astrophysics Data System (ADS)

Barchfeld, Robert Adam

Worldwide demand for power, and in particular electricity, is growing. Increasing population, expanding dependence on electrical devices, as well as the development of emerging nations, has created significant challenges for the power production. Compounding the issue are concerns over pollution, natural resource supplies, and political obstacles in troubled parts of the world. Many believe that investment in renewable energy will solve the expected energy crisis; however, renewable energy has many shortfalls. Consequently, additional sources of energy should be explored to provide the best options for the future. Electricity from fusion power offers many advantages over competing technologies. It can potentially produce large amounts of clean energy, without the serious concerns of fission power plant safety and nuclear waste. Fuel supplies for fusion are plentiful. Fusion power plants can be operated as needed, without dependence on location, or local conditions. However, there are significant challenges before fusion can be realized. Many factors currently limit the effectiveness of fusion power, which prevents a commercial power plant from being feasible. Scientists in many countries have built, and operate, experimental fusion plants to study the fusion process. The leading examples are magnetic confinement reactors known as tokamaks. At present, reactor gain is near unity, where the fusion power output is nearly the same as the power required to operate the reactor. A tenfold increase in gain is what reactors such as ITER hope to achieve, where 50 MW will be used for plasma heating, magnetic fields, and so forth, with a power output of 500 MW. Before this can happen, further research is required. Loss of particle and energy confinement is a principal cause of low performance; therefore, increasing confinement time is key. There are many causes of thermal and particle transport that are being researched, and the prime tools for conducting this research are plasma diagnostics. Plasma diagnostics collect data from fusion reactors in a number of different ways. Among these are far infrared (FIR) laser based systems. By probing a fusion plasma with FIR lasers, many properties can be measured, such as density and density fluctuations. This dissertation discusses the theory and design of two laser based diagnostic instruments: 1) the Far Infrared Tangential Interferometer and Polarimeter (FIReTIP) systems, and 2) the High-ktheta Scattering System. Both of these systems have been designed and fabricated at UC Davis for use on the National Spherical Torus Experiment - Upgrade (NSTX-U), located at Princeton Plasma Physics Laboratory (PPPL). These systems will aid PPPL scientists in fusion research. The FIReTIP system uses 119 ?m methanol lasers to pass through the plasma core to measure a chord averaged plasma density through interferometry. It can also measure the toroidal magnetic field strength by the way of polarimetery. The High-ktheta Scattering System uses a 693 GHz formic acid laser to measure electron scale turbulence. Through collective Thomson scattering, as the probe beam passes through the plasma, collective electron motion will scatter power to a receiver with the angle determined by the turbulence wavenumber. This diagnostic will measure ktheta from 7 to 40 cm-1 with a 4-channel receiver array. The High-ktheta Scattering system was designed to facilitate research on electron temperature gradient (ETG) modes, which are believed to be a major contributor to anomalous transport on NSTX-U. The design and testing of these plasma diagnostics are described in detail. There are a broad range of components detailed including: optically pumped gas FIR lasers, overmoded low loss waveguide, launching and receiving optical designs, quasi-optical mixers, electronics, and monitoring and control systems. Additionally, details are provided for laser maintenance, alignment techniques, and the fundamentals of nano-CNC-machining.

Plasma chemistry as a tool for green chemistry, environmental analysis and waste management.

PubMed

Mollah, M Y; Schennach, R; Patscheider, J; Promreuk, S; Cocke, D L

2000-12-15

The applications of plasma chemistry to environmental problems and to green chemistry are emerging fields that offer unique opportunities for advancement. There has been substantial progress in the application of plasmas to analytical diagnostics and to waste reduction and waste management. This review discusses the chemistry and physics necessary to a basic understanding of plasmas, something that has been missing from recent technical reviews. The current status of plasmas in environmental chemistry is summarized and emerging areas of application for plasmas are delineated. Plasmas are defined and discussed in terms of their properties that make them useful for environmental chemistry. Information is drawn from diverse fields to illustrate the potential applications of plasmas in analysis, materials modifications and hazardous waste treatments.

Progress in Development of C60 Nanoparticle Plasma Jet for Diagnostic of Runaway Electron Beam-Plasma Interaction and Disruption Mitigation Study for ITER

NASA Astrophysics Data System (ADS)

Bogatu, I. N.; Thompson, J. R.; Galkin, S. A.; Kim, J. S.

2013-10-01

We produced a C60 nanoparticle plasma jet (NPPJ) with uniquely fast response-to-delivery time (~ 1 - 2 ms) and unprecedentedly high momentum (~ 0 . 6 g .km/s). The C60 NPPJ was obtained by using a solid state TiH2/C60 pulsed power cartridge producing ~180 mg of C60 molecular gas by sublimation and by electromagnetic acceleration of the C60 plasma in a coaxial gun (~35 cm length, 96 kJ energy) with the output of a high-density (>1023 m-3) hyper-velocity (>4 km/s) plasma jet. The ~ 75 mg C60/C plasma jet has the potential to rapidly and deeply deliver enough mass to significantly increase electron density (to ne ~ 2 . 4 ×1021 m-3, i.e. ~ 60 times larger than typical DIII-D pre-disruption value, ne 0 ~ 4 ×1019 m-3), and to modify the 'critical electric field' and the runaway electrons (REs) collisional drag during different phases of REs dynamics. The C60 NPPJ, as a novel injection technique, allows RE beam-plasma interaction diagnostic by quantitative spectroscopy of C ions visible/UV line intensity. The system is scalable to ~ 1 - 2 g C60/C plasma jet output and technology is adaptable to ITER acceptable materials (BN and Be) for disruption mitigation. Work supported by US DOE DE-FG02-08ER85196 grant.

Thomson Parabola Spectrometer: a powerful tool to get on-line plasma information

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

Altana, C.; Universita degli Studi di Catania - Dip.to di Fisica e Astronomia - Catania; Schillaci, F.

2015-07-01

In this contribution we report the results of an experimental measurement performed with a TPS developed at INFN-LNS within the ELIMED project, by means of a powerful and self-consistent technique as a diagnostic tool for the ionic acceleration study in laser-generated-plasmas. (authors)

Plasma emission spectroscopy method of tumor therapy

DOEpatents

Fleming, Kevin J.

1997-01-01

Disclosed are a method and apparatus for performing photon diagnostics using a portable and durable apparatus which incorporates the use of a remote sensing probe in fiberoptic communication with an interferometer or spectrometer. Also disclosed are applications for the apparatus including optically measuring high velocities and analyzing plasma/emission spectral characteristics.

Characterization of a dielectric barrier discharge in contact with liquid and producing a plasma activated water

NASA Astrophysics Data System (ADS)

Neretti, G.; Taglioli, M.; Colonna, G.; Borghi, C. A.

2017-01-01

In this work a low-temperature plasma source for the generation of plasma activated water (PAW) is developed and characterized. The plasma reactor was operated by means of an atmospheric-pressure air dielectric barrier discharge (DBD). The plasma generated is in contact with the water surface and is able to chemically activate the liquid medium. Electrodes were supplied by both sinusoidal and nanosecond-pulsed voltage waveforms. Treatment times were varied from 2 to 12 min to increase the energy dose released to the water by the DBD plasma. The physics of the discharge was studied by means of electrical, spectroscopic and imaging diagnostics. The interaction between the plasma and the liquid was investigated as well. Temperature and composition of the treated water were detected. Images of the discharges showed a filamentary behaviour in the sinusoidal case and a more homogeneous behaviour in the nanosecond-pulsed one. The images and the electrical measurements allowed to evaluate an average electron number density of about 4  ×  1019 and 6  ×  1017 m-3 for the sinusoidal and nanosecond-pulsed discharges respectively. Electron temperatures in the range of 2.1÷2.6 eV were measured by using spectroscopic diagnostics. Rotational temperatures in the range of 318-475 K were estimated by fitting synthetic spectra with the measured ones. Water temperature and pH level did not change significantly after the exposure to the DBD plasma. The production of ozone and hydrogen peroxide within the water was enhanced by increasing the plasma treatment time and the energy dose. Numerical simulations of the nanosecond-pulsed discharge were performed by using a self-consistent coupling of state-to-state kinetics of the air mixture with the Boltzmann equation of free electron kinetics. Temporal evolution of the electron energy distribution function shows departure from the Maxwellian distribution especially during the afterglow phase of the discharge. When limited deviations from Maxwellian distribution were observed, calculated electron temperature is in good agreement with the one measured by means of spectroscopic diagnostics. Computed temporal evolution of the energy delivered to the discharge is comparable with the one obtained from electrical measurements. The electrical discharges supplied by both voltage waveforms produce plasma activated water with negligible thermal effects and pH variations.

Interaction of Intense Lasers and Relativistic Electron Beams with Solids, Gases and Plasmas

DTIC Science & Technology

1993-06-01

June 18, 1993. The main subject was the identification of research opportunities and needs that are at- tractive for investigation using the HAARP ...warming and global change. Highly leveraged cooperative or collaborative programs exploring the HAARP facility and diagnostic complement in conjunction...1. Diagnostic issues - HF diagnostics. 1.1 Possible use of HAARP transmitter as a receiving antenna. 1.2 Possible addition of a "big" receiving

Optical Measurements of Air Plasma

DTIC Science & Technology

2008-05-05

beam impact ionization of air was studied in the context of optical diagnostics . The electron beam originates in a pulsed 100 keV 20-mA source and...range of 636 Torr to 1 mTorr with pulse durations from 1 ms to 10 ms. Microwave diagnostics were used to quantify electron density and power; and an...optical diagnostic was used to quantify ozone production. An additional effort to quantify byproducts of electron impact ionization, that are

Neutron monitoring and electrode calorimetry experiments in the HIP-1 Hot Ion Plasma

NASA Technical Reports Server (NTRS)

Reinmann, J. J.; Layman, R. W.

1977-01-01

Results are presented for two diagnostic procedures on HIP-1: neutron diagnostics to determine where neutrons originated within the plasma discharge chamber and electrode calorimetry to measure the steady-state power absorbed by the two anodes and cathodes. Results are also reported for a hot-ion plasma formed with a continuous-cathode rod, one that spans the full length of the test section, in place of the two hollow cathodes. The outboard neutron source strength increased relative to that at the midplane when (1) the cathode tips were moved farther outboard, (2) the anode diameters were increased, and (3) one of the anodes was removed. The distribution of neutron sources within the plasma discharge chamber was insensitive to the division of current between the two cathodes. For the continuous cathode, increasing the discharge current increased the midplane neutron source strength relative to the outboard source strength. Each cathode absorbed from 12 to 15 percent of the input power regardless of the division of current between the cathodes. The anodes absorbed from 20 to 40 percent of the input power. The division of power absorption between the anodes varied with plasma operating conditions and electrode placement.

Development of optical diagnostics for performance evaluation of arcjet thrusters

NASA Technical Reports Server (NTRS)

Cappelli, Mark A.

1995-01-01

Laser and optical emission-based measurements have been developed and implemented for use on low-power hydrogen arcjet thrusters and xenon-propelled electric thrusters. In the case of low power hydrogen arcjets, these laser induce fluorescence measurements constitute the first complete set of data that characterize the velocity and temperature field of such a device. The research performed under the auspices of this NASA grant includes laser-based measurements of atomic hydrogen velocity and translational temperature, ultraviolet absorption measurements of ground state atomic hydrogen, Raman scattering measurements of the electronic ground state of molecular hydrogen, and optical emission based measurements of electronically excited atomic hydrogen, electron number density, and electron temperature. In addition, we have developed a collisional-radiative model of atomic hydrogen for use in conjunction with magnetohydrodynamic models to predict the plasma radiative spectrum, and near-electrode plasma models to better understand current transfer from the electrodes to the plasma. In the final year of the grant, a new program aimed at developing diagnostics for xenon plasma thrusters was initiated, and results on the use of diode lasers for interrogating Hall accelerator plasmas has been presented at recent conferences.

Te and H_α Measurements on the HT-7 Tokamak: A Collaboration between the Fusion Research Center and the Institute of Plasma Physics

NASA Astrophysics Data System (ADS)

Winslow, D. L.; Carter, K. R.; Chatterjee, R.; Huang, H.; Phillips, P. E.; Rowan, W. L.; Kuang, G. L.; Li, J. G.; Luo, J. R.; Wan, B. N.; Wan, Y. X.; Xie, J. K.

1998-11-01

A team from the Fusion Research Center at the University of Texas at Austin visited the HT-7 Tokamak at the Institute of Plasma Physics at the Chinese Academy of Sciences in Hefei, Anhui, China to study the effects of lower hybrid current drive (LHCD) in the HT-7 plasma. HT-7(HT-7 Group, Fusion Energy 1996 Vol. 1, 685 (1997).) is a medium-sized (R = 1.22 m) tokamak with superconducting toroidal field coils and long--pulse capabilities utilizing LHCD to assist ohmic current drive. Core and edge diagnostics supported by a stand-alone data acquisition system were installed for the spring 1998 campaign. The diagnostics included an ECE radiometer which allows determination of both electron temperature profiles and fluctuation levels in the core plasma and an H_α array detector for measurement of turbulence in regions not easily accessible to probes. In addition, a reciprocating Langmuir probe system was developed for use on HT-7 and should be available for the next campaign. The effects of LHCD upon fluctuation levels in the plasma will be discussed.

Runaway electron generation and control

NASA Astrophysics Data System (ADS)

Esposito, B.; Boncagni, L.; Buratti, P.; Carnevale, D.; Causa, F.; Gospodarczyk Martin-Solis, M., Jr.; Popovic, Z.; Agostini, M.; Apruzzese, G.; Bin, W.; Cianfarani, C.; De Angelis, R.; Granucci, G.; Grosso, A.; Maddaluno, G.; Marocco, D.; Piergotti, V.; Pensa, A.; Podda, S.; Pucella, G.; Ramogida, G.; Rocchi, G.; Riva, M.; Sibio, A.; Sozzi, C.; Tilia, B.; Tudisco, O.; Valisa, M.; FTU Team

2017-01-01

We present an overview of FTU experiments on runaway electron (RE) generation and control carried out through a comprehensive set of real-time (RT) diagnostics/control systems and newly installed RE diagnostics. An RE imaging spectrometer system detects visible and infrared synchrotron radiation. A Cherenkov probe measures RE escaping the plasma. A gamma camera provides hard x-ray radial profiles from RE bremsstrahlung interactions in the plasma. Experiments on the onset and suppression of RE show that the threshold electric field for RE generation is larger than that expected according to a purely collisional theory, but consistent with an increase due to synchrotron radiation losses. This might imply a lower density to be targeted with massive gas injection for RE suppression in ITER. Experiments on active control of disruption-generated RE have been performed through feedback on poloidal coils by implementing an RT boundary-reconstruction algorithm evaluated on magnetic moments. The results indicate that the slow plasma current ramp-down and the simultaneous reduction of the reference plasma external radius are beneficial in dissipating the RE beam energy and population, leading to reduced RE interactions with plasma facing components. RE active control is therefore suggested as a possible alternative or complementary technique to massive gas injection.

Soft x-ray pinhole imaging diagnostics for compact toroid plasmas

NASA Astrophysics Data System (ADS)

Crawford, E. A.; Taggart, D. P.; Bailey, A. D., III

1990-10-01

Soft x-ray pinhole imaging has recently become established as a valuable diagnostic for visualization of field reversed configuration (FRC) plasmas in the TRX-2, FRX-C/LSM devices. Gated MCP image converter devices with CsI cathodes and Be filters with a peak response around 11 nm wavelength are used for exposure durations ranging from a few tenths up to several microseconds. Results of experiments with single and Chevron channel plates are discussed along with estimates of linear exposure limitations with both film and CCD cameras as recording media. Plans for multiframe devices on the FRX-C/LSM and the LSX devices are also discussed.

The remarkably high excitation planetary nebula GC 6537

PubMed Central

Aller, Lawrence H.; Hung, Siek; Feibelman, Walter A.

1999-01-01

NGC 6537 is an unusually high excitation point symmetric planetary nebula with a rich spectrum. Its kinematical structures are of special interest. We are here primarily concerned with the high resolution spectrum as revealed by the Hamilton echelle Spectrograph at Lick Observatory (resolution ≈ 0.2 Å) and supplemented by UV and near-UV data. These extensive data permit a determination of interstellar extinction, plasma diagnostics, and ionic concentrations. The photoionization models that have been used successfully for many planetary nebulae are not entirely satisfactory here. The plasma electron temperature of a photoionization model cannot much exceed 20,000 K, but plasma diagnostics show that regions emitting radiation of highly ionized atoms such as [Neiv] and [Nev] are much hotter, showing that shock excitation must be important, as suggested by the remarkable kinematics of this object. Hence, instead of employing a strict photoionization model, we are guided by the nebular diagnostics, which reveal how electron temperature varies with ionization potential and accommodates density effects. The predictions of the photoionization model may be useful in estimating ionization correction factor. In effect, we have estimated the chemical composition by using both photoionization and shock considerations. PMID:10318889

Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic

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

Swadling, G. F.; Ross, J. S.; Datte, P.

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause “blanking” (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimatedmore » to be ∼8 J cm{sup −2}. This is significantly above the expected threshold for the onset of “blanking” effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate “blanking.” Estimates suggest that an areal density of 10{sup 19} cm{sup −2} Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented.« less

Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic

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

Swadling, G. F.; Ross, J. S.; Datte, P.

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Labs (LLNL). This diagnostic is designed to make measurements of hohlraum plasma parameters, such as the electron temperature and density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature hohlraums produce intense soft x-ray emission, which can cause “blanking” (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated tomore » be ~ 8 J cm -2. This is then significantly above the expected threshold for the onset of “blanking” effects. A novel Xenon Plasma X-ray Shield (XPXS) has been proposed to protect the blast shield from x-rays and mitigate “blanking”. Finally, these estimates suggest that an areal density of 10 19 cm -2 Xe atoms will be sufficient to absorb 99.5% the soft x-ray flux. Two potential designs for this shield are presented.« less

Coherent anti-Stokes Raman scattering and spontaneous Raman scattering diagnostics of nonequilibrium plasmas and flows

NASA Astrophysics Data System (ADS)

Lempert, Walter R.; Adamovich, Igor V.

2014-10-01

The paper provides an overview of the use of coherent anti-Stokes Raman scattering (CARS) and spontaneous Raman scattering for diagnostics of low-temperature nonequilibrium plasmas and nonequilibrium high-enthalpy flows. A brief review of the theoretical background of CARS, four-wave mixing and Raman scattering, as well as a discussion of experimental techniques and data reduction, are included. The experimental results reviewed include measurements of vibrational level populations, rotational/translational temperature, electric fields in a quasi-steady-state and transient molecular plasmas and afterglow, in nonequilibrium expansion flows, and behind strong shock waves. Insight into the kinetics of vibrational energy transfer, energy thermalization mechanisms and dynamics of the pulse discharge development, provided by these experiments, is discussed. Availability of short pulse duration, high peak power lasers, as well as broadband dye lasers, makes possible the use of these diagnostics at relatively low pressures, potentially with a sub-nanosecond time resolution, as well as obtaining single laser shot, high signal-to-noise spectra at higher pressures. Possibilities for the development of single-shot 2D CARS imaging and spectroscopy, using picosecond and femtosecond lasers, as well as novel phase matching and detection techniques, are discussed.

The remarkably high excitation planetary nebula GC 6537.

PubMed

Aller, L H; Hung, S; Feibelman, W A

1999-05-11

NGC 6537 is an unusually high excitation point symmetric planetary nebula with a rich spectrum. Its kinematical structures are of special interest. We are here primarily concerned with the high resolution spectrum as revealed by the Hamilton echelle Spectrograph at Lick Observatory (resolution approximately 0.2 A) and supplemented by UV and near-UV data. These extensive data permit a determination of interstellar extinction, plasma diagnostics, and ionic concentrations. The photoionization models that have been used successfully for many planetary nebulae are not entirely satisfactory here. The plasma electron temperature of a photoionization model cannot much exceed 20,000 K, but plasma diagnostics show that regions emitting radiation of highly ionized atoms such as [NeIV] and [NeV] are much hotter, showing that shock excitation must be important, as suggested by the remarkable kinematics of this object. Hence, instead of employing a strict photoionization model, we are guided by the nebular diagnostics, which reveal how electron temperature varies with ionization potential and accommodates density effects. The predictions of the photoionization model may be useful in estimating ionization correction factor. In effect, we have estimated the chemical composition by using both photoionization and shock considerations.

Progress in neutron-, X-ray- and VIS spectroscopic diagnostics of large-scale plasma focus experiments at ICDMP

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

Schmidt, Hellmut

Substantial progress has been made in various diagnostics for investigating results of experiments during the last years performed with the PF1000 device at IPPLM, Warsaw, Poland. In addition to standard diagnostics of the electrical characteristics of up to 1 MJ discharges in a Mather type plasma focus geometry, such as high speed photography, X-ray, fast electron beam and time-integrated neutron measurements, there have been made among others at least three quite successful efforts recently: 1) Setting up of a neutron time-of-flight line with up to five scintillation detectors including optical fibre based data collection equipment, 2) Use of a Mechellemore » spectrometer with CCD registration and possibility to take time-resolved spectra with resolutions down to 100 ns and 3) Setting up and using pinhole cameras equipped with solid state nuclear track detectors for the detection of fusion generated protons. Correlations of emission events as well as plasma and electrical current dynamics are investigated. Neutron emission characteristics and fusion products production mechanisms are discussed considering a generalized beam target model, called Gyrating Particle Model.« less

Design calculations for a xenon plasma x-ray shield to protect the NIF optical Thomson scattering diagnostic

DOE PAGES

Swadling, G. F.; Ross, J. S.; Datte, P.; ...

2016-07-21

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Labs (LLNL). This diagnostic is designed to make measurements of hohlraum plasma parameters, such as the electron temperature and density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature hohlraums produce intense soft x-ray emission, which can cause “blanking” (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated tomore » be ~ 8 J cm -2. This is then significantly above the expected threshold for the onset of “blanking” effects. A novel Xenon Plasma X-ray Shield (XPXS) has been proposed to protect the blast shield from x-rays and mitigate “blanking”. Finally, these estimates suggest that an areal density of 10 19 cm -2 Xe atoms will be sufficient to absorb 99.5% the soft x-ray flux. Two potential designs for this shield are presented.« less

First measurements of Dα spectrum produced by anisotropic fast ions in the gas dynamic trap

NASA Astrophysics Data System (ADS)

Lizunov, A.; Anikeev, A.

2014-11-01

Angled injection of eight deuterium beams in gas dynamic trap (GDT) plasmas builds up the population of fast ions with the distribution function, which conserves a high degree of initial anisotropy in space, energy, and pitch angle. Unlike the Maxwellian distribution case, the fast ion plasma component in GDT cannot be exhaustively characterized by the temperature and density. The instrumentation complex to study of fast ions is comprised of motional Stark effect diagnostic, analyzers of charge exchange atoms, and others. The set of numerical codes using for equilibrium modeling is also an important tool of analysis. In the recent campaign of summer 2014, we recorded first signals from the new fast ion D-alpha diagnostic on GDT. This paper presents the diagnostic description and results of pilot measurements. The diagnostic has four lines of sight, distributed across the radius of an axially symmetric plasma column in GDT. In the present setup, a line-integrated optical signal is measured in each channel. In the transverse direction, the spatial resolution is 18 mm. Collected light comes to the grating spectrometer with the low-noise detector based on a charge-coupled device matrix. In the regime of four spectra stacked vertically on the sensor, the effective spectral resolution of measurements is approximately 0.015 nm. Exposure timing is provided by the fast optical ferroelectric crystal shutter, allowing frames of duration down to 70 μs. This number represents the time resolution of measurements. A large dynamic range of the camera permits for a measurement of relatively small light signals produced by fast ions on top of the bright background emission from the bulk plasma. The fast ion emission has a non-Gaussian spectrum featuring the characteristic width of approximately 4 nm, which can be separated from relatively narrow Gaussian lines of D-alpha and H-alpha coming from the plasma periphery, and diagnostic beam emission. The signal to noise ratio varies from approximately ten for the central channel to approximately five for the outermost channel. We used the special set of Monte Carlo codes to fit the measured spectra. The shape of model fit shows a good agreement with the experimental fast ion D-alpha spectrum.

Plasma-free vs deconjugated metanephrines for diagnosis of phaeochromocytoma.

PubMed

Pamporaki, Christina; Därr, Roland; Bursztyn, Michael; Glöckner, Stephan; Bornstein, Stefan R; Lenders, Jacques W M; Pacak, Karel; Krinner, Axel; Eisenhofer, Graeme

2013-10-01

The diagnosis of phaeochromocytoma is commonly performed by the measurements of plasma-free normetanephrine and metanephrine. Plasma-deconjugated normetanephrine and metanephrine have been proposed as alternative, equivalent, but easier to measure biomarkers. The aim of this study was to compare the diagnostic performance of plasma-free vs deconjugated normetanephrine and metanephrine in patients tested for phaeochromocytoma. The study population included a reference group of 262 normotensive and hypertensive volunteers, 198 patients with phaeochromocytoma and 528 patients initially suspected of having the tumour, but with negative investigations after at least 2 years of follow-up. Measurements were performed using liquid chromatography with electrochemical detection. Plasma concentrations of free normetanephrine were 17-fold higher in patients with phaeochromocytoma than in the reference population, a 72% larger (P < 0·001) difference than that for the 10-fold higher levels of plasma-deconjugated normetanephrine. In contrast, relative increases in plasma concentrations of free and deconjugated metanephrine were similar. Using upper cut-offs established in the reference population, measurements of plasma-free metabolites provided superior diagnostic performance than deconjugated metabolites according to measures of both sensitivity (97% vs 92%, P = 0·002) and specificity (93% vs 89%, P = 0·012). The area under the receiver operating characteristic curve for the free metabolites was larger than that for the deconjugated metabolites (0·986 vs 0·965, P < 0·001). Measurements of plasma-free normetanephrine and metanephrine are superior to the deconjugated metabolites for diagnosis of phaeochromocytoma. © 2013 John Wiley & Sons Ltd.

Studies of RF sheaths and diagnostics on IShTAR

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

Crombé, K., E-mail: Kristel.Crombe@UGent.be; LPP-ERM/KMS, Royal Military Academy, Brussels; Devaux, S.

2015-12-10

IShTAR (Ion cyclotron Sheath Test ARrangement) is a linear magnetised plasma test facility for RF sheaths studies at the Max-Planck-Institut für Plasmaphysik in Garching. In contrast to a tokamak, a test stand provides more liberty to impose the parameters and gives better access for the instrumentation and antennas. The project will support the development of diagnostic methods for characterising RF sheaths and validate and improve theoretical predictions. The cylindrical vacuum vessel has a diameter of 1 m and is 1.1 m long. The plasma is created by an external cylindrical plasma source equipped with a helical antenna that has been designed tomore » excite the m=1 helicon mode. In inductive mode, plasma densities and electron temperatures have been characterised with a planar Langmuir probe as a function of gas pressure and input RF power. A 2D array of RF compensated Langmuir probes and a spectrometer are planned. A single strap RF antenna has been designed; the plasma-facing surface is aligned to the cylindrical plasma to ease the modelling. The probes will allow direct measurements of plasma density profiles in front of the RF antenna, and thus a detailed study of the density modifications induced by RF sheaths, which influences the coupling. The RF antenna frequency has been chosen to study different plasma wave interactions: the accessible plasma density range includes an evanescent and propagative behaviour of slow or fast waves, and allows the study of the effect of the lower hybrid resonance layer.« less

Additive Manufacture (3D Printing) of Plasma Diagnostic Components and Assemblies for Fusion Experiments

NASA Astrophysics Data System (ADS)

Quinley, Morgan; Chun, Katherine; Melnik, Paul; Sieck, Paul; Smith, Trevor; Stuber, James; Woodruff, Simon; Romero-Talamas, Carlos; Rivera, William; Card, Alexander

2016-10-01

We are investigating the potential impact of additive manufacturing (3D printing) on the cost and complexity of plasma diagnostics. We present a survey of the current state-of-the-art in additive manufacture of metals, as well as the design of diagnostic components that have been optimized for and take advantage of these processes. Included among these is a set of retarding field analyzer probe heads that have been printed in tungsten with internal heat sinks and cooling channels. Finite element analysis of these probe heads shows the potential for a 750K reduction in peak temperature, allowing the probe to take data twice as often without melting. Results of the evaluation of these probe heads for mechanical strength and outgassing, as well as their use on Alcator C-Mod will be presented. Supported by DOE SBIR Grant DE-SC0011858.

Final case for a stainless steel diagnostic first wall on ITER

NASA Astrophysics Data System (ADS)

Pitts, R. A.; Bazylev, B.; Linke, J.; Landman, I.; Lehnen, M.; Loesser, D.; Loewenhoff, Th.; Merola, M.; Roccella, R.; Saibene, G.; Smith, M.; Udintsev, V. S.

2015-08-01

In 2010 the ITER Organization (IO) proposed to eliminate the beryllium armour on the plasma-facing surface of the diagnostic port plugs and instead to use bare stainless steel (SS), simplifying the design and providing significant cost reduction. Transport simulations at the IO confirmed that charge-exchange sputtering of the SS surfaces would not affect burning plasma operation through core impurity contamination, but a second key issue is the potential melt damage/material loss inflicted by the intense photon radiation flashes expected at the thermal quench of disruptions mitigated by massive gas injection. This paper addresses this second issue through a combination of ITER relevant experimental heat load tests and qualitative theoretical arguments of melt layer stability. It demonstrates that SS can be employed as material for the port plug plasma-facing surface and this has now been adopted into the ITER baseline.

Reproducible diagnostic metabolites in plasma from typhoid fever patients in Asia and Africa.

PubMed

Näsström, Elin; Parry, Christopher M; Vu Thieu, Nga Tran; Maude, Rapeephan R; de Jong, Hanna K; Fukushima, Masako; Rzhepishevska, Olena; Marks, Florian; Panzner, Ursula; Im, Justin; Jeon, Hyonjin; Park, Seeun; Chaudhury, Zabeen; Ghose, Aniruddha; Samad, Rasheda; Van, Tan Trinh; Johansson, Anders; Dondorp, Arjen M; Thwaites, Guy E; Faiz, Abul; Antti, Henrik; Baker, Stephen

2017-05-09

Salmonella Typhi is the causative agent of typhoid. Typhoid is diagnosed by blood culture, a method that lacks sensitivity, portability and speed. We have previously shown that specific metabolomic profiles can be detected in the blood of typhoid patients from Nepal (Näsström et al., 2014). Here, we performed mass spectrometry on plasma from Bangladeshi and Senegalese patients with culture confirmed typhoid fever, clinically suspected typhoid, and other febrile diseases including malaria. After applying supervised pattern recognition modelling, we could significantly distinguish metabolite profiles in plasma from the culture confirmed typhoid patients. After comparing the direction of change and degree of multivariate significance, we identified 24 metabolites that were consistently up- or down regulated in a further Bangladeshi/Senegalese validation cohort, and the Nepali cohort from our previous work. We have identified and validated a metabolite panel that can distinguish typhoid from other febrile diseases, providing a new approach for typhoid diagnostics.

Innovative single-shot diagnostics for electrons accelerated through laser-plasma interaction at FLAME

NASA Astrophysics Data System (ADS)

Bisesto, F. G.; Anania, M. P.; Chiadroni, E.; Cianchi, A.; Costa, G.; Curcio, A.; Ferrario, M.; Galletti, M.; Pompili, R.; Schleifer, E.; Zigler, A.

2017-05-01

Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (> 100 GV/m), enabling acceleration of electrons to GeV energy in few centimeters. Here we present all the plasma related activities currently underway at SPARC LAB exploiting the high power laser FLAME. In particular, we will give an overview of the single shot diagnostics employed: Electro Optic Sampling (EOS) for temporal measurement and optical transition radiation (OTR) for an innovative one shot emittance measurements. In detail, the EOS technique has been employed to measure for the first time the longitudinal profile of electric field of fast electrons escaping from a solid target, driving the ions and protons acceleration, and to study the impact of using different target shapes. Moreover, a novel scheme for one shot emittance measurements based on OTR, developed and tested at SPARC LAB LINAC, will be shown.