Publications

2013

• Conditions for ion-ion plasma formation in the PEGASES II thruster
  
  • Grondein Pascaline
  • Bredin Jérôme
  • Aanesland Ane
  , 2013.
• Physics and design of wide-aperture bipolar particle sources
  
  • Stanislav Dudin
  • Aanesland Ane
  , 2013.
• Status on the Project of Laser Based Production, Acceleration and Neutralization of High Power Neutral (H or D) Beam for Demo Application
  
  • Moustaizis Stavros
  • Auvray Philippe
  • Larour Jean
  • Perrakis C.
  • Ducret J.-E.
  , 2013. communication orale
• Origin of extracted H- ions at different plasma grid bias in caesiated ion sources
  
  • Bacal M.
  • Mcadams R.
  • Surrey E.
  , 2013.
• Generation of High Pulsed magnetic field using low inductance switches
  
  • Auvray Philippe
  • Larour Jean
  • Moustaizis Stavros
  , 2013. On présente plusieurs dispositifs de production de courants intenses (jusqu'à 900 kA sous 30 kV) pour magnétiser des volumes d'interaction laser-matière de quelques cm3 pendant environ 1 µs. L'accent est mis sur la réalisation de deux types d'éclateur à très faible inductance et sur la connexion à une chambre à vide.
• Numerical Evaluation of the Role of Reflectors to Maximize the Power Efficiency of an Axial Vircator (keynote)
  
  • Champeaux Stéphanie
  • Gouard Philippe
  • Cousin Richard
  • Larour Jean
  , 2013, pp.4A-High Power Microwaves I. Keynote speech on HPM. The effects of introducing one or more reflectors inside an axial Vircator are analyzed using CST-Particle Studio (TM) PIC simulation. The power conversion efficiency is shown to be enhanced from 1% to 13% at 3 GHz. The optimum output power is obtained with three reflectors. Abstract disponible sur http://www.ivec2013.org/ Texte de 2 pages sur clé USB distribué aux participants mais non public.
• Propagation of Plasmas in Liquids
  
  • Rousseau Antoine
  , 2013.
• Guiding of meter scale AC discharges by laser filamentation in air
  
  • Houard Aurélien
  • Brelet Yohann
  • Point G.
  • Carbonnel Jérôme
  • André Y-B.
  • Prade Bernard S.
  • Arantchouk Léonid
  • Mysyrowicz André
  , 2013. We report experiments of laser-guided discharges obtained in air with high voltage bursts delivered by a compact Tesla coil. Characteristics of the guided discharges are studied for electrode gaps ranging from 30 to 170 cm.
• Plasma column from laser filamentation in air as a virtual radio-frequency antenna
  
  • Point G.
  • Brelet Yohann
  • Houard Aurélien
  • Carbonnel Jérôme
  • Arantchouk Léonid
  • Prade Bernard S.
  • André Y-B.
  • Mysyrowicz André
  , 2013. We demonstrate the use of a plasma column created by femtosecond filamentation and heated by means of a high-voltage discharge communication orale CD-10.1
• Dynamics of Cl<SUB>2</SUB> inductively-coupled plasmas: Role of electronic and vibrational excitation
  
  • Booth Jean-Paul
  • Sirse Nishant
  • Chabert Pascal
  • Indelicato P.
  • Surzhykov A.
  • Kushner M.J.
  , 2013.
• Development of plasma and beam diagnostics for the PEGASES thruster experiment
  
  • Rafalskyi D.V.
  • Aanesland Ane
  , 2013.
• A simple high-voltage high current spark gap with subnanosecond jitter triggered by femtosecond laser filamentation
  
  • Arantchouk Léonid
  • Houard Aurélien
  • Brelet Yohann
  • Carbonnel Jérôme
  • Larour Jean
  • André Yves-Bernard
  • Mysyrowicz André
  Applied Physics Letters, American Institute of Physics, 2013, 102 (16), pp.162502. We describe a simple, sturdy, and reliable spark gap operating with air at atmospheric pressure and able to switch currents in excess of 10 kA with sub-nanosecond jitter. The spark gap is remotely triggered by a femtosecond laser filament. (10.1063/1.4802927)
  DOI : 10.1063/1.4802927
• Observation of a poloidal asymmetry of fluctuation perpendicular velocity measured by Doppler backscattering on Tore Supra plasmas
  
  • Storelli A.
  • Hennequin Pascale
  • Vermare Laure
  • Gürcan Özgür D.
  • Tore Supra Team
  , 2013 (oral).
• Doppler backscattering measurements on TCV
  
  • Vermare Laure
  • Coda S.
  • Hennequin Pascale
  • de Meijere K.
  • Honoré Cyrille
  • Giacalone J-C.
  • Tcv Team
  , 2013 (oral).
• The optimized steerable W-band Doppler reflectometer on ASDEX Upgrade: possibilities and issues
  
  • Happel T.
  • Conway G. D.
  • Hennequin Pascale
  • Honoré Cyrille
  • Giacalone J-C.
  • Simon P.
  • Stroth U.
  • Vermare Laure
  • Asdex Upgrade Team The
  , 2013 (http://www.lptp.polytechnique.fr/News/11/Workshop/papers/Happel_IRW11-paper.pdf).
• Damping of Geodesic Acoustic Modes.
  
  • Vermare Laure
  • Hennequin Pascale
  • Gürcan Özgür D.
  • Morel Pierre
  • Tore Supra Team
  , 2013 (oral).
• Geodesic acoustic modes:ffsimultaneous observation of density,ff magnetic-field, and flow componentsff in the TCV tokamak
  
  • Coda S.
  • de Meijere K.
  • Huang Z.
  • Vermare Laure
  • Vernay T.
  • Vuille V.
  • Brunner Stephan
  • Dominski J.
  • Hennequin Pascale
  • Krämer-Flecken A.
  • Merlo G.
  • Porte L.
  , 2013 (oral).
• Spatial propagation of turbulence and formation of mesoscopic structures in GK simulations
  
  • Dif-Pradalier Guilhem
  • Ghendrih Ph.
  • Diamond P.H.
  • Garbet X.
  • Grandgirard V.
  • Palermo F.
  • Sarazin Y.
  • Strugarek Antoine
  • Abitboul J.
  • Gürcan Özgür D.
  • Hennequin Pascale
  • Morel Pierre
  • Vermare Laure
  , 2013 (http://ttf2013.ucsd.edu/TTF_Meeting/Home.html).
• Formation of the Earth's Ion Foreshock in the quasi-perpendicular collisionless shock region: Full-particle 2D simulation results
  
  • Savoini Philippe
  • Lembège Bertrand
  • Stienlet J.
  , 2013, 15, pp.4978. The ion foreshock located upstream of the Earth's shock front is populated with ions having interacted with the shock and then are reflected back with an high energy gain. In situ spacecrafts measurements have firmly established the existence of two distinct populations in the foreshock usptream of quasi-perpendicular shock region (i.e. for 45° &#8804; &#920;Bn &#8804; 90°, where &#920;Bn is the angle between the shock normal and the upstream magnetostatic field): (i) field-aligned (FAB) ion beams characterized by a gyrotropic distribution, and (ii) gyro-phase bunched (GPB) ions characterized by a NON gyrotropic distribution, which exhibit a non-vanishing perpendicular bulk velocity. Then, the purpose of the present work is to identify the different possible sources of backstreaming ions and is based on the use of 2D PIC simulations of a curved shock, where full curvature effects, time of flight effects and both electrons and ions dynamics are fully described by a self consistent approach. Our analysis evidences that these two populations mentionned above may have different origins identified both in terms of interaction time and distance of penetration. In particular, ours simulations evidence that "GPB" and FAB populations are characterized by a short (&#916;Tinter = 1 to 2 tci) and much larger (&#916;Tinter = 1 to 10 tci) interaction time respectively, where tci is the upstream ion gyroperiod. A deeper analysis of both individual and statistical ion trajectories evidences that: (i) both populations can be discriminated in terms of injection angle into the shock front (i.e. defined between the normal to the shock front and the gyration velocity vector when ions reach the shock). Such a behavior explains how reflected ions can be splitted in the observed two populations "FAB" and "GPB". (ii) ion trajectories differ between the "FAB" and "GPB" populations at the shock front. In particular, FAB and GPB ions suffer respectively multi-bounces and one bounce only. (iii) the drift associated to the "FAB" ions allows them to scan a &#920;Bn range between 10° and 20° (in the quasi-perpendicular domain) which accounts for their gyrotropic distribution (loss of their initial gyro-phase which is not the case for the "GPB" ions). Consequences on parallel energy gain will be illustrated with particles trajectories typical of each population.
• Density Holes, Hot Flow Anomalies and SLAMS Upstream of Earth's Bow Shock
  
  • Parks G. K.
  • Lee E.
  • Lin N.
  • Canu Patrick
  • Fu Suiyan
  • Cao J.B.
  • Dandouras I.
  • Rème H.
  • Goldstein M. L.
  , 2013, 15, pp.EGU2013-5584. Density holes (DH), Hot Flow Anomalies (HFA) and Short Large Amplitude Magnetic Structures (SLAMS) are transient structures observed in the upstream region of Earth's bow shock. The densities in these structures are depleted and in some cases as much as 99% of the ambient solar wind (SW) density. Moreover, the velocity moments of the SW show slow down and diversion in front of these structures. These structures, which can be as short as 4s (spin period of the spacecraft), are seen only when back-streaming particles are present. But not all backstreaming particles produce upstream structures and the conditions for forming these structures still remain unknown. In 2010 and 2011, the Cluster plasma ion experiment was configured to sample 3D distributions of the SW and the backstreaming particles with spin period time resolution (4s). These results show the SW beam in the hole is persistent and that evolving structures can be produced within existing DHs, HFAs and SLAMS. We present new observations of upstream structures including examples of how the structures can evolve into shocks.
• Heavy ion dynamics at Mercury
  
  • Delcourt Dominique
  , 2013. The MESSENGER spacecraft was inserted into orbit about Mercury on March 18 2011. Particle measurements from the FIPS instrument onboard this spacecraft reveal abundant populations of heavy ions such as O and Na in all magnetospheric regions. These ions appear to significantly contribute to thermal pressure, particularly in the nightside equatorial region where they can account for up to one third of the proton pressure. These heavy ion populations that originate from the planet surface via a variety of processes (e.g., thermal desorption, solar wind sputtering, micro-meteoritic bombardment...) thus have to be considered for a comprehensive investigation of the magnetosphere structure and dynamics at Mercury. We will review some transport features of these heavy ions of planetary origin. These features include : large scale convection from dayside cusp to nightside plasma sheet and subsequent nonadiabatic transport in the magnetotail, impulsive energization during short-lived reconfigurations of the magnetosphere, as well as centrifugally stimulated escape from the exosphere. We will also discuss the fate of planetary ions entering into the magnetosphere from the magnetosheath and their ring-like distribution at low latitudes.
• Eleven years of Cluster observations of whistler-mode chorus
  
  • Santolík O.
  • Macusova E.
  • Kolmasova Ivana
  • Cornilleau-Wehrlin Nicole
  • Pickett J. S.
  , 2013, 15, pp.EGU2013-10234. Electromagnetic emissions of whistler-mode chorus carry enough power to increase electron fluxes in the outer Van Allen radiation belt at time scales on the order of one day. However, the ability of these waves to efficiently interact with relativistic electrons is controlled by the wave propagation directions and time-frequency structure. Eleven years of measurements of the STAFF-SA and WBD instruments onboard the Cluster spacecraft are systematically analyzed in order to determine the probability density functions of propagation directions of chorus as a function of geomagnetic latitude, magnetic local time, L* parameter, and frequency. A large database of banded whistler-mode emissions and time-frequency structured chorus has been used for this analysis. This work has received EU support through the FP7-Space grant agreement no 284520 for the MAARBLE collaborative research project.
• Broadband AC/DC hybrid magnetometer for space plasmas science
  
  • Mansour Malik
  • Coillot Christophe
  • Dau Frédéric Nguyen Van
  • Roux A.
  , 2013, 15, pp.EGU2013-10155. Broadband AC/DC hybrid magnetometer for space plasmas science
• From 1AU solar wind turbulence backward to coronal turbulence: an inverse problem
  
  • Dong Yue
  • Verdini Andrea
  • Grappin Roland
  , 2013, 15, pp.3285. This work deals with the formation of the low-frequency spectrum of solar wind turbulence, including the so-called inertial range and the lower frequency 1/f range. Much is known on the turbulent state of the solar wind plasma at distances larger than 0.3 AU, but few is known on the turbulent state of the plasma at the sources of the wind, like the coronal plasma. Characterizing the turbulence state of plasma in the solar corona is thus an inverse problem. To solve this inverse problem, we use the MHD expanding box model, which consists in incorporating in the MHD equations the effects of expansion on a turbulent plasma volume advected by a wind with constant (radial) velocity, by using comobile coordinates. In spite of its limitations (assumption of constant expansion), the model includes the basic effects of expansion (i) anisotropic damping of velocity and magnetic field (ii) weakening of nonlinear coupling in the perpendicular directions. The code allows in particular to follow the 3D turbulent evolution of the kinetic and magnetic energy spectra. We present here for the first time numerical solutions of the expanding 3D MHD equations by starting with different initial conditions: we follow the turbulent evolution of the plasma box imbedded in a radial wind up to 1 AU and compare the final turbulent state with observations, thus allowing us to determine which initial conditions are acceptable. We vary three kinds of initial parameters: (1) spectral/components anisotropy (2) Alfvén species imbalance (3) kinetic/magnetic imbalance. The connection of the results with available models of the formation of coronal turbulence is discussed at the end.
• Evidence of coherent drift-resonant acceleration of radiation belt particles by ULF waves
  
  • Sauvaud J.-A.
  • Walt M.
  • Delcourt Dominique C.
  • Benoist C.
  • Penou E.
  • Chen Y.
  • Russell Christopher T.
  , 2013, 15, pp.EGU2013-1830. Evidence is presented for frequent, coherent and powerful accelerations of radiation belt electrons and protons during magnetic storms. Geomagnetic storms are indeed frequently associated with the formation of well developed, multiple bands of energetic electrons inside the inner radiation belt at L=1.1-1.9 and with prominent similar energy structures of protons inside the slot region at L=2.2-3.5. These structures typically from 100 keV up to the MeV range result from coherent interactions of energetic particles with quasi- monochromatic Ultra Low Frequency waves (ULF). These waves are induced by magnetospheric changes due to the arrival of dense solar material and related nightside injections of particles from the outer magnetosphere that destabilize field lines in the inner magnetosphere down to L=1.1. We show that, at the low altitudes of the Demeter spacecraft, these structures are best seen near the South Atlantic Anomaly because of lowering of the belt particle mirror point. As evidenced from ground measurements, energy bands are associated with quasi-sinusoidal ULF Pc5 and Pc4 waves with periods in the 1000 second range for L = 1.1-1.9 and in the 60 second range for L=2.2-3.5. Numerical simulations of the coherent drift resonance of energetic particles with Ultra Low Frequency waves show how the particles are accelerated and how the observed structures build up. The structures are formed for interaction times of the order of 20-40 minutes. For longer resonance times, particles are accelerated at energies higher than 1.5 MeV while lower energy particles are decelerated.