Schlieren imaging in a dielectric barrier discharge actuator for airflow control
A. Cristofolini, G. Neretti, F. Roveda, and C. A. Borghi
The operation of a surface dielectric barrier discharge actuator for airflow control has been experimentally investigated. The actuator is constituted by an electrode pair separated by a dielectric Teflon sheet. Several ac supply conditions have been utilized. An electrohydrodynamics interaction was ... [J. Appl. Phys. 111, 033302 (2012)] published Fri Feb 10, 2012.
Study of space charge compensation phenomena in charged particle beams
P. Veltri, M. Cavenago, and G. Serianni
The propagation of a charged particle beam is accompanied by the production of secondary particles created in the interaction of the beam itself with the background gas flowing in the accelerator tube. In the drift region, where the electric field of the electrodes is negligible, secondary particles ... [Rev. Sci. Instrum. 83, 02B709 (2012)] published Fri Feb 10, 2012.
Sheath structure in negative ion sources for fusion (invited)
R. McAdams, D. B. King, A. J. T. Holmes, and E. Surrey
In fusion negative ion sources, the negative ions are formed on the caesiated plasma grid predominantly by hydrogen atoms from the plasma. The space charge of the negative ions leaving the wall is not fully compensated by incoming positive ions and at high enough emission a virtual cathode is formed ... [Rev. Sci. Instrum. 83, 02B109 (2012)] published Fri Feb 10, 2012.
Progress in the MITICA beam source design
P. Zaccaria, P. Agostinetti, D. Marcuzzi, M. Pavei, N. Pilan et al.
In the framework of the development of the ITER neutral beam (NB) system, a test facility is planned to be built in Padova. A full size prototype of the ITER heating NB injector (MITICA) shall be built and tested at full beam power (17 MW) as per ITER requirements. The design of the MITICA beam sour ... [Rev. Sci. Instrum. 83, 02B108 (2012)] published Fri Feb 10, 2012.
Concepts for the magnetic design of the MITICA neutral beam test facility ion accelerator
G. Chitarin, P. Agostinetti, N. Marconato, D. Marcuzzi, E. Sartori et al.
The megavolt ITER injector concept advancement neutral injector test facility will be constituted by a RF-driven negative ion source and by an electrostatic Accelerator, designed to produce a negative Ion with a specific energy up to 1 MeV. The beam is then neutralized in order to obtain a focused 1 ... [Rev. Sci. Instrum. 83, 02B107 (2012)] published Fri Feb 10, 2012.
A close-coupling multi-antenna type radio frequency driven ion source
Y. Oka and T. Shoji
A newly close coupling multi-antenna type radio frequency driven ion source is tested for the purpose of essentially improving plasma coupling on the basis of our old type ion source, which reuses a NNBI (negative ion source for neutral beam injection) ion source used in 1/5th scale of the Large Hel ... [Rev. Sci. Instrum. 83, 02B106 (2012)] published Fri Feb 10, 2012.
A 3D Monte Carlo code for the modeling of plasma dynamics and beam formation mechanism in electron cyclotron resonance ion sources
L. Neri, D. Mascali, L. Celona, S. Gammino, and G. Ciavola
The code here presented is the first part of a Monte Carlo (MC) self-consistent 3D plasma simulator. It is yet able to solve the equation of motion for thousands of independent charged particles. The procedure allows to understand the consequences of each phenomenon introduced in the evolution steps ... [Rev. Sci. Instrum. 83, 02A330 (2012)] published Fri Feb 10, 2012.
Design and fabrication of a superconducting magnet for an 18 GHz electron cyclotron resonance ion/photon source NFRI-ECRIPS
H.-J. You, S.-W. Jang, Y.-H. Jung, T.-H. Lho, and S.-J. Lee
A superconducting magnet was designed and fabricated for an 18 GHz ECR ion/photon source, which will be installed at National Fusion Research Institute (NFRI) in South Korea. The magnetic system consists of a set of four superconducting coils for axial mirror field and 36 pieces of permanent magnets ... [Rev. Sci. Instrum. 83, 02A326 (2012)] published Fri Feb 10, 2012.
Multicharged ion source based on Penning-type discharge with electron cyclotron resonance heating by millimeter waves
A. V. Vodopyanov, I. V. Izotov, D. A. Mansfeld, and G. Yu. Yushkov
We suggest a Penning-type discharge as a trigger discharge for fast development of pulsed electron cyclotron resonance plasma. The Penning-type discharge glows at a low pressure as needed. Gyrotron radiation (75 GHz, 200 kW, 1 ms) was used for plasma heating. Fully striped helium ions were demonstra ... [Rev. Sci. Instrum. 83, 02A325 (2012)] published Fri Feb 10, 2012.
Assessment of ozone generation in dry air fed silent discharge reactors
Ashraf Yehia
Two equations have been derived in this paper for expecting the ozone generation inside dry air fed silent discharge reactors. The derived equations have been built on theories of the silent discharges and their applications, reported in the literature. The two equations have been investigated indiv ... [Phys. Plasmas 19, 023503 (2012)] published Thu Feb 9, 2012.
Nonplanar electron acoustic shock waves in a plasma with electrons featuring Tsallis distribution
Biswajit Sahu and Mouloud Tribeche
The properties of cylindrical and spherical electron acoustic shock waves (EASWs) in an unmagnetized plasma consisting of cold electrons, immobile ions, and hot electrons featuring Tsallis statistics are investigated by employing the reductive perturbation technique. A Korteweg-de Vries Burgers (KdV ... [Phys. Plasmas 19, 022304 (2012)] published Thu Feb 9, 2012.
Changes in density fluctuations as a result of resonant magnetic perturbations correlate with the density inverse scale length
S. Mordijck, R. A. Moyer, and G. R. McKee
In this paper we show that the changes in ion-scale density fluctuations n/n induced by resonant magnetic perturbations (RMPs) exhibit the same trends as modifications to the inverse density scale length, a/L in the pedestal area. In a series of ITER similar shape (ISS) H-mode discharges in DIII-D, ... [Phys. Plasmas 19, 024504 (2012)] published Thu Feb 9, 2012.
Relativistic critical density increase and relaxation and high-power pulse propagation
S. M. Weng, P. Mulser, and Z. M. Sheng
High-power laser pulse propagation in an overdense plasma due to the relativistic critical density increase has been investigated in one dimension. In a first step the conditions for the existence of a relativistic critical density are delimited and supported by particle-in-cell simulations. Its acc ... [Phys. Plasmas 19, 022705 (2012)] published Thu Feb 9, 2012.
Excitation wavelength dependence of water-window line emissions from boron-nitride laser-produced plasmas
M. Crank, S. S. Harilal, S. M. Hassan, and A. Hassanein
We investigated the effects of laser excitation wavelength on water-window emission lines of laser-produced boron-nitride plasmas. Plasmas are produced by focusing 1064 nm and harmonically generated 532 and 266 nm radiation from a Nd:YAG laser on BN target in vacuum. Soft x-ray emission lines in the ... [J. Appl. Phys. 111, 033301 (2012)] published Thu Feb 9, 2012.
Target normal sheath acceleration analytical modeling, comparative study and developments
C. Perego, D. Batani, A. Zani, and M. Passoni
Ultra-intense laser interaction with solid targets appears to be an extremely promising technique to accelerate ions up to several MeV, producing beams that exhibit interesting properties for many foreseen applications. Nowadays, most of all the published experimental results can be theoretically ex ... [Rev. Sci. Instrum. 83, 02B502 (2012)] published Thu Feb 9, 2012.
Electron cyclotron resonance plasma production by using pulse mode microwaves and dependences of ion beam current and plasma parameters on the pulse condition
Ryutaro Kiriyama, Tomoya Takenaka, Yousuke Kurisu, Dai Nozaki, Fuminobu Sato et al.
We measure the ion beam current and the plasma parameters by using the pulse mode microwave operation in the first stage of a tandem type ECRIS. The time averaged extracted ion beam current in the pulse mode operation is larger than that of the cw mode operation with the same averaged microwave powe ... [Rev. Sci. Instrum. 83, 02A324 (2012)] published Thu Feb 9, 2012.
Performance and operation of advanced superconducting electron cyclotron resonance ion source SECRAL at 24 GHz
H. W. Zhao, W. Lu, X. Z. Zhang, Y. C. Feng, J. W. Guo et al.
SECRAL (superconducting ECR ion source with advanced design in Lanzhou) ion source has been in routine operation for Heavy Ion Research Facility in Lanzhou (HIRFL) accelerator complex since May 2007. To further enhance the SECRAL performance in order to satisfy the increasing demand for intensive hi ... [Rev. Sci. Instrum. 83, 02A320 (2012)] published Thu Feb 9, 2012.
Influence of the shear flow on electron cyclotron resonance plasma confinement in an axisymmetric magnetic mirror trap of the electron cyclotron resonance ion source
I. V. Izotov, S. V. Razin, A. V. Sidorov, V. A. Skalyga, V. G. Zorin et al.
Influence of shear flows of the dense plasma created under conditions of the electron cyclotron resonance (ECR) gas breakdown on the plasma confinement in the axisymmetric mirror trap (vortex confinement) was studied experimentally and theoretically. A limiter with bias potential was set inside the ... [Rev. Sci. Instrum. 83, 02A318 (2012)] published Thu Feb 9, 2012.
Optimizing conversion efficiency and reducing ion energy in a laser-produced Gd plasma
Thomas Cummins, Takamitsu Otsuka, Noboru Yugami, Weihua Jiang, Akira Endo et al.
We have demonstrated an efficient extreme ultraviolet (EUV) source at 6.7 nm by irradiating Gd targets with 0.8 and 1.06 [mu]m laser pulses of 140 fs to 10 ns duration. Maximum conversion efficiency of 0.4% was observed within a 0.6% bandwidth. A Faraday cup observed ion yield and time of flight sig ... [Appl. Phys. Lett. 100, 061118 (2012)] published Thu Feb 9, 2012.
Publisher's Note: Controlled Betatron X-Ray Radiation from Tunable Optically Injected Electrons [Phys. Rev. Lett. 107, 255003 (2011)]
S. Corde, K. Ta Phuoc, R. Fitour, J. Faure, A. Tafzi et al.
Abstract not available. [Phys. Rev. Lett. 108, 069901 ] published .
Electronic Detection of Collective Modes of an Ultracold Plasma
K. A. Twedt and S. L. Rolston
Using a new technique to directly detect current induced on a nearby electrode, we measure plasma oscillations in ultracold plasmas, which are influenced by the inhomogeneous and time-varying density and changing neutrality. Electronic detection avoids heating and evaporation dynamics associated wit ... [Phys. Rev. Lett. 108, 065003 ] published .
Transport-Driven Toroidal Rotation in the Tokamak Edge
T. Stoltzfus-Dueck
The interaction of passing-ion drift orbits with spatially inhomogeneous but purely diffusive radial transport is demonstrated to cause spontaneous toroidal spin-up in a simple model of the tokamak edge. Physically, major-radial orbit shifts cause orbit-averaged diffusivities to depend on v, includi ... [Phys. Rev. Lett. 108, 065002 ] published .
Fully kinetic description of the linear excitation and nonlinear saturation of fast-ion-driven geodesic acoustic mode instability
D. Zarzoso, X. Garbet, Y. Sarazin, R. Dumont, and V. Grandgirard
We show in this paper that geodesic acoustic modes (GAMs) can be efficiently excited by a population of fast ions even when Landau damping on thermal ions is accounted for. We report in particular fully kinetic calculations of the GAM dispersion relation and its complete solution. Written under a va ... [Phys. Plasmas 19, 022102 (2012)] published Wed Feb 8, 2012.
Channeling dynamics of relativistic-intensity laser pulses
A. Friou, E. Lefebvre, and L. Gremillet
Two-dimensional particle-in-cell simulations were performed to study the channeling in long (>500[mu]m) underdense plasmas of long duration (>10 ps), relativistic-intensity (I=10 W/cm) laser pulses. We describe five different types of channeling behaviors, and the corresponding ranges of plasmas and ... [Phys. Plasmas 19, 022704 (2012)] published Wed Feb 8, 2012.
Characterization of cluster/monomer ratio in pulsed supersonic gas jets
X. Gao, X. Wang, B. Shim, A. V. Arefiev, R. Korzekwa et al.
We determine cluster mass fraction f(r,t) at position r within, and time t after firing, a pulsed supersonic gas jet by measuring femtosecond evolution of the jet's refractive index by single-shot frequency domain holography. A fs pump pulse singly ionizes monomers, while quasi-statically ionizing a ... [Appl. Phys. Lett. 100, 064101 (2012)] published Wed Feb 8, 2012.
Plasma resonances in a microwave-driven microdischarge
J. Xue, R. S. Urdahl, and J. E. Cooley
This work investigates resonances in a capacitively coupled, low pressure krypton microdischarge operated at 2.5 GHz. A circuit model for the device, which has a length dimension of approximately 1 mm, calculates impedance values for a range of electron densities. The model results predict several p ... [Appl. Phys. Lett. 100, 064102 (2012)] published Wed Feb 8, 2012.
Dynamical Coupling between Gradients and Transport in Fusion Plasmas
C. Hidalgo, C. Silva, B. A. Carreras, B. van Milligen, H. Figueiredo et al.
The dynamical coupling between density gradients and particle transport has been investigated using similar experimental tools in the plasma boundary of different tokamak (JET, ISTTOK) and stellarator (TJ-II) devices, showing that the size of turbulent events is minimum in the proximity of the most ... [Phys. Rev. Lett. 108, 065001 ] published .
Effects of magnetic shear on magneto-Rayleigh-Taylor instability
Peng Zhang, Y. Y. Lau, I. M. Rittersdorf, M. R. Weis, R. M. Gilgenbach et al.
The magnetized liner inertial fusion concept [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] consists of a cylindrical metal liner enclosing a preheated plasma that is embedded in an axial magnetic field. Because of its diffusion into the liner, the pulsed azimuthal magnetic field may exhibit ... [Phys. Plasmas 19, 022703 (2012)] published Tue Feb 7, 2012.
Measurement of ion and electron temperatures in plasma blobs by using an improved ion sensitive probe system and statistical analysis methods
K. Okazaki, H. Tanaka, N. Ohno, N. Ezumi, Y. Tsuji et al.
We have measured ion temperature as well as electron temperature in plasma blobs observed in a linear plasma device by using an improved ion sensitive probe. Currentvoltage characteristics of the ion sensitive probe inside and outside plasma blobs were re-constructed with a conditional sampling meth ... [Rev. Sci. Instrum. 83, 023502 (2012)] published Tue Feb 7, 2012.
The dependence of extracted current on discharge gas pressure in neutral beam ion sources on HL-2A tokamak
H. L. Wei, J. Y. Cao, J. Rao, G. J. Lei, S. F. Jiang et al.
The discharge gas pressure is a key factor to influence the extracted current of ion source. In this paper, the dependence of extracted current on discharge gas pressure was investigated in detail at different arc discharge currents. The discharge gas pressure with a very broad range (0.1 Pa2.7 Pa) ... [Rev. Sci. Instrum. 83, 023302 (2012)] published Tue Feb 7, 2012.
In situ crystallization kinetics studies of plasma-deposited, hydrogenated amorphous silicon layers
K. Sharma, M. A. Verheijen, M. C. M. van de Sanden, and M. Creatore
The impact of the amorphous silicon properties, i.e., the microstructure parameter R* and the medium range order (MRO), on the crystallization process is highlighted and discussed. In agreement with literature, the development of large grains extending through the thickness of the poly-Si layer is f ... [J. Appl. Phys. 111, 033508 (2012)] published Mon Feb 6, 2012.
Nonlinear entropy transfer via zonal flows in gyrokinetic plasma turbulence
M. Nakata, T.-H. Watanabe, and H. Sugama
Nonlinear entropy transfer processes in toroidal ion temperature gradient (ITG) and electron temperature gradient (ETG) driven turbulence are investigated based on the gyrokinetic entropy balance relations for zonal and non-zonal modes, which are coupled through the entropy transfer function regarde ... [Phys. Plasmas 19, 022303 (2012)] published Mon Feb 6, 2012.
Dynamic mitigation of instabilities
S. Kawata
In the paper Phys. Plasmas 18, 092705 (2011), dynamic stabilization mechanism for the Rayleigh-Taylor instability was discussed together with another dynamic migration mechanism, which we proposed and is discussed further in a more general way in this paper. In general, a perturbation of physical qu ... [Phys. Plasmas 19, 024503 (2012)] published Mon Feb 6, 2012.
Comparison between off-resonance and electron Bernstein waves heating regime in a microwave discharge ion source
G. Castro, D. Mascali, F. P. Romano, L. Celona, S. Gammino et al.
A microwave discharge ion source (MDIS) operating at the Laboratori Nazionali del Sud of INFN, Catania has been used to compare the traditional electron cyclotron resonance (ECR) heating with an innovative mechanisms of plasma ignition based on the electrostatic Bernstein waves (EBW). EBW are obtain ... [Rev. Sci. Instrum. 83, 02B501 (2012)] published Mon Feb 6, 2012.
Diagnostics of the ITER neutral beam test facility
R. Pasqualotto, G. Serianni, P. Sonato, M. Agostini, M. Brombin et al.
The ITER heating neutral beam (HNB) injector, based on negative ions accelerated at 1 MV, will be tested and optimized in the SPIDER source and MITICA full injector prototypes, using a set of diagnostics not available on the ITER HNB. The RF source, where the H/D production is enhanced by cesium eva ... [Rev. Sci. Instrum. 83, 02B103 (2012)] published Mon Feb 6, 2012.
Matrix of small-radius radio-frequency discharges as a volume-production based source of negative hydrogen ions
St. Lishev, Ts. Paunska, A. Shivarova, and Kh. Tarnev
Based on experience from a workboth theoretical and experimental oneon negative hydrogen ion beam sources studied regarding fusion applications, a novel design of a rf source with volume production of the ions is proposed. The suggestion is for a source constructed as a matrix of small-radius tandem ... [Rev. Sci. Instrum. 83, 02A702 (2012)] published Mon Feb 6, 2012.
Improved chopping of a lithium beam for plasma edge diagnostic at ASDEX Upgrade
M. Willensdorfer, E. Wolfrum, R. Fischer, J. Schweinzer, M. Sertoli et al.
The lithium beam diagnostic at ASDEX Upgrade routinely delivers electron density profiles in the plasma edge by lithium beam impact excitation spectroscopy. An accurate background subtraction requires a periodically chopped lithium beam. A new, improved chopping system was developed and installed. I ... [Rev. Sci. Instrum. 83, 023501 (2012)] published Mon Feb 6, 2012.
Relativistic magnetohydrodynamics in one dimension
Maxim Lyutikov and Samuel Hadden
We derive a number of solutions for one-dimensional dynamics of relativistic magnetized plasma that can be used as benchmark estimates in relativistic hydrodynamic and magnetohydrodynamic numerical codes. First, we analyze the properties of simple waves of fast modes propagating orthogonally to the ... [Phys. Rev. E 85, 026401 ] published .
On the breaking of a plasma wave in a thermal plasma: I. The structure of the density singularity. (arXiv:1202.1903v1 [physics.plasm-ph])
ePrint arXiv http://arXiv.org/
On the breaking of a plasma wave in a thermal plasma: II. Electromagnetic wave interaction with the breaking plasma wave. (arXiv:1202.1907v1 [physics.plasm-ph])
ePrint arXiv http://arXiv.org/
Electronic detection of collective modes of an ultracold plasma. (arXiv:1110.6909v2 [physics.plasm-ph] UPDATED)
ePrint arXiv http://arXiv.org/