Publications

2009

• Principle and Performance of a Dual-Band Search Coil Magnetometer: A New Instrument to Investigate Fluctuating Magnetic Fields in Space
  
  • Coillot Christophe
  • Moutoussamy Joël
  • Lebourgeois Richard
  • Ruocco Sébastien
  • Chanteur Gérard
  IEEE Sensors Journal, Institute of Electrical and Electronics Engineers, 2009, 10 (2), pp.255-260. Search-coil magnetometers are of common use in space physics thanks to their simplicity, robustness and ability to measure weak magnetic fields: their sensitivity can reach a few tens of in the range 10-100 kHz. The frequency band is grossly determined by the resonance of the coil. Simply adding a second coil does not efficiently extend the frequency band beyond the first resonance due to the mutual impedance of the two coils. We present a solution, called "mutual reducer," which allows us to take full benefit of the second coil and efficiently extends the frequency band. The physical principle is described first, followed by a detailed presentation of this "dual-band search-coil" (DBSC) that will be part of the Plasma Wave Instrument (PWI) onboard the Mercury Magnetospheric Orbiter (MMO) of the ESA-JAXA mission BepiColombo dedicated to the exploration of the plasma environment of planet Mercury. (10.1109/JSEN.2009.2030977)
  DOI : 10.1109/JSEN.2009.2030977
• Wave vector directions of whistler-mode chorus
  
  • Santolík O.
  • Pickett J. S.
  • Gurnett D. A.
  • Macusova E.
  • Menietti J. D.
  • Cornilleau-Wehrlin Nicole
  • Tsurutani B. T.
  • Verkhoglyadova O. P.
  , 2009, 44, pp.01. Whistler-mode chorus has been shown to play a significant role in acceleration of relativistic electrons in the outer Van Allen radiation belt. It can also propagate from its source region and influence large regions of the inner magnetosphere. Distribution of the wave energy density in the space of the wave vector directions is a crucial parameter for modeling of both the wave-particle interactions and wave propagation in the inner magnetosphere. We present a survey of observations of whistler-mode chorus emissions by the Plasma Wave Instrument on the Polar spacecraft in 1996 and 1997 together with a large data set obtained by the STAFF-SA instruments onboard the CLUSTER spacecraft. We show that highly oblique propagation needs to be considered in the radiation belt models.
• Cascade and Dissipation of Solar Wind Turbulence at Electron Scales: Whistlers or Kinetic Alfven Waves?
  
  • Sahraoui Fouad
  • Goldstein M. L.
  , 2009, pp.A3.
• Solar wind ablation of terrestrial planet atmospheres
  
  • Moore T. E.
  • Fok M.-C. H.
  • Delcourt Dominique
  , 2009.
• Observation of proton chorus waves close to the equatorial plane by Cluster
  
  • Grison B.
  • Pickett J. S.
  • Santolík O.
  • Robert Patrick
  • Cornilleau-Wehrlin Nicole
  • Engebretson M. J.
  • Constantinescu D. O.
  , 2009, 44, pp.04. Whistler mode chorus waves are a widely studied phenomena. They are present in numerous regions of the magnetosphere and are presumed to originate in the magnetic equatorial region. In a spectrogram they are characterized by narrowband features with rise (or fall) in frequency over short periods of time. Being whistler mode waves around a few tenths of the electron cyclotron frequency they interact mainly with electrons. In the present study we report observations by the Cluster spacecraft of what we call proton chorus waves. They have spectral features with rising frequency, similar to the electron chorus waves, but they are detected in a frequency range that starts roughly at 0.50fH up to fH (the local proton gyro-frequency). The lower part of their spectrum seems to originate from monochromatic Pc 1 waves (1.5 Hz). Proton chorus waves are detected close to the magnetic equatorial plane in both hemispheres during the same event. Our interpretation of these waves as proton chorus is supported by polarization analysis with the Roproc procedures and the Prassadco software using both the magnetic (STAFF-SC) and electric (EFW) parts of the fluctuations spectrum.
• Sources of two-dimensional supercritical perpendicular shock nonstationarity: nonlinear whistler emission versus shock front self-reformation
  
  • Lembège Bertrand
  • Savoini Philippe
  • Hellinger P.
  • Travnicek Pavel
  , 2009, 31, pp.1452. Two-dimensional (2-D) full particle electromagnetic simulations are used for analysing in detail different nonstationary behaviors of perpendicular supercritical shocks (Lembège et al., 2009). A recent study (Hellinger et al., 2007) has previously evidenced that the shock front is dominated by the emission of coherent large amplitude whistler waves for some plasma conditions and shock regimes. These whistler waves are emitted in two-dimensional perpendicular shocks and inhibit the self-reformation driven by the accumulation of reflected ions: then, the shock front appears almost "quasistationary", a result which could seem in apparent contradiction with previous results. The present study allows to clarify the situation by bringing new complementary results:(i) there exists a transition regime around a critical Mach number threshold Mwwe, within which both self-reformation and whistler waves emission can co-exist. (ii) Below (above) this threshold regime, the self-reformation (whistler waves emission) is fully retrieved and becomes dominant. (iii) As MA is larger than Mwwe, this shock front looks "quasi-stationary" in 1-D y-averaged fields profiles, but in fact is nonstationary in full 2-D profiles. Moreover, this nonstationarity is characterized by a quasi-periodic reinforcement of nonlinear waves emission from the ramp. This effect results from the fact that the emission of nonlinear whistler waves varies in time according to the local need for balancing the nonlinear effects at the shock ramp (steepening). (iv) These results are observed for a strictly perpendicular shock, as B0 is within the simulation plane; in contrast, as B0 is perpendicular to the simulation plane, no whistler waves emission is evidenced even for large Mach number; only self-reformation is observed. The coexistence of both processes within the transition regime is characterized by a rapid occurrence of the self-reformation at early time of a run, while nonlinear waves are dominating the whole shock dynamics at later times of the same run. A parametric study shows that effectively the growth of these nonlinear waves is strongly dependant on the time, and increases drastically as the Mach number is above the threshold Mwwe. Present results, even if unexpected, are shown to be in a good agreement with previous 2D PIC and 2D hybrid simulations these are compared with. References : HELLINGER P., P. TRAVICEK, B. LEMBEGE and P. SAVOINI . Emission of nonlinear whistler waves at the front of perpendicular supercritical shocks: Hybrid versus full particle simulations J. Geophys. Res. , VOL. 34, L14109, doi:10.1029/2007GL030239, 2007 LEMBEGE B. , P. SAVOINI, P. HELLINGER and P.M. TRAVNICEK Nonstationarity of a two-dimensional perpendicular shock: competing mechanims J. Geophys. Res., 114, A03217, doi:10.1029/2008JA013618, 2009
• Statistical study of ionospheric ion beams observed by CLUSTER above the polar caps
  
  • Maggiolo R.
  • Echim M.
  • Fontaine Dominique
  • Teste A. F.
  • Jacquey C.
  , 2009, 33, pp.1569. Above the polar caps and during prolonged periods of Northward IMF, the Cluster spacecraft detect accelerated ion beams with energies up to a few keV. They are associated with downward precipitating electrons and converging electric field structures indicating that the acceleration is caused by a quasi-static field aligned electric field that can extend to altitudes up to 5 RE (Maggiolo et al. 2006, Teste et al. 2007). Using the AMDA science analysis service provided by the Centre de Données de la Physique des Plasmas (CDPP, http://cdpp.cesr.fr), we have been able to extract from the Cluster ion detectors dataset the time periods when Cluster encounters polar cap local ion beams. 6 years of data have been mined with this tool. Almost 200 events have been found giving new insight on these structures. After a description of the method used for the automatic detection of the beams, we will discuss their statistical properties. We analyze their relation to solar wind and IMF. In particular, we estimate the delay between a Northward/Southward turning of the IMF and the appearance/disappearance of these beams. The characteristics of the particles detected inside these structures as well as their size, orientation and location are also presented. We show that these ion beams are located on magnetic field lines mapping close to the high latitude magnetopause and in the central part of the lobes and that 40 % of them are detected together with hot isotropic ions. These results will be discussed in term of magnetotail configuration during prolonged periods of Northward IMF.
• First In-Situ Observation of Rolled-up Kelvin-Helmholtz Vortices under Southward IMF with Evidence of Reconnection
  
  • Goldstein M. L.
  • Hwang J.
  • Sahraoui Fouad
  • Lee E.
  • Parks G. K.
  , 2009, pp.B1530.
• 2D PIC simulations of a curved supercritical shock: dynamics of the whistler precursor
  
  • Stienlet J.
  • Lembège Bertrand
  • Savoini Philippe
  , 2009, 31, pp.1454. The whistler precursor emitted from the curved terrestrial shock front plays an important role in pre-decelerating and heating the incoming solar wind. Most previous works have mainly analyzed the features of the whistler precursor emission for a 1D planar shock where it is forced to propagate along the shock normal (Liewer and al, 1991) or to propagate obliquely with respect to a fixed shock normal direction in 2D planar shock simulation (Krauss-Varban et al., 1995). In the present case, the dynamics of the precursor is analyzed for a full curved shock with the help of a 2D full particle simulation where full curvature effects and both electrons and ions dynamics are described by a self consistent approach. Curvature effects continously cover all shock normal directions within the angular range 90° <= thetaBn <= 45° where thetaBn is the angle between the shock normal and the upstream magnetostatic field. This approach allows a free accessibility of the whistler precursor to a large angular range without any constraint. Preliminary results show that : (i) the whistler precursor strongly extends far from the shock front mainly along the magnetostatic field (projected on the simulation plane) but this extension is progressively reduced outside this privileged direction; (ii) wave fronts of the whistler precursor have a curvature similar to that of the main curved shock front but the width of these curved wave fronts strongly decreases when moving far from the shock front; (iii) near the shock front, the precursor is emitted within an angular range much larger than that predicted by linear theory; (iv) the critical angle of occurrence of the precursor fits with the theoretical value expected from Krasnoselskikh et al. (2002) model but this angle is not associated to a transition between stationary and non-stationary shocks in contrast with a statement announced by this theoretical model; and (v) the damping rate of the whistler precursor is analyzed for different directions of the shock normal and compared with previous modes (Gary et Mellott, 1985). These results will be discussed and compared with previous 1D and 2D simulations of planar shocks. References: Gary S. P. and M.M.Mellott, Whistler Damping at oblique propagation: Laminar Shock Precursors, J. Geophys .Res., 1985. Liewer J., K. Decyk, J.M. Dawson and B. Lembege, Numerical Studies of Electron Dynamics in Oblique Quasi-Perpendicular Collisionless Shock Waves, J. Geophys.Res. ,96, 9455, 1991. Krauss-Varban D., F. Pantellini et D. Burgess, Electron dynamics and whistler waves at quasi-perpendicular shocks , G. Res. Lett., 22, 16, 2091, 1995 Krasnoselskikh V. , B. Lembège, P. Savoini and V.V. Lobzin, Nonstationarity of strong Collisionless quasiperpendicular shocks: theory and full particle simulations, Phys. Plasma, 9, 4, 1192, 2002.
• Electron scale turbulence in the solar wind
  
  • Sahraoui Fouad
  • Goldstein M. L.
  • Belmont Gérard
  • Khotyaintsev Y. V.
  • Kiyani K. H.
  • Robert Patrick
  , 2009.
• Dynamic Martian Magnetosphere: Transient Twist Induced by a Rotation of the IMF
  
  • Chanteur Gérard
  • Modolo Ronan
  • Dubinin Eduard
  , 2009, 14, pp.abstract id.P14B-06. Simulation studies of the Martian environment are usually restricted to stationary situations under various static conditions of the solar wind and solar radiation. Dynamic transients and their implications have so far attracted little attention although global simulation models can provide valuable insights to understand disagreements between simulations and in situ observations. We make use for the first time of the three dimensional multispecies hybrid simulation model that we have developed (Modolo et al., Ann. Geophys., 23, 433, 2005) to investigate the response of the Martian plasma environment to a sudden rotation of the IMF. The simulation model couples charged and neutral species via three ionisation mechanisms: the absorption of solar extreme ultraviolet radiation, the impacts of solar wind electrons, and the charge exchanges between ions and neutral atoms or molecules. When a rotational discontinuity conveyed by the solar wind reaches the Martian environment the bow shock adapts quickly to the new solar wind conditions in contrast to the induced magnetosphere, especially the magnetic lobes in the wake. Timescales necessary to recover a stationary state can be estimated from such simulations, and implications for space observations will be discussed, especially the use of magnetic field proxies for ordering particle measurements made by a spacecraft like Mars Express without an onboard magnetometer. Moreover the spatial distribution of escaping ion fluxes being significantly modified by time dependant solar wind conditions, a reassessment of simulated escape is worth the effort in order to improve the comparison with fluxes derived from observations.
• Nouvelles solutions de capteurs à effet de magnétoimpédance géante : principe, modélisation et performances
  
  • Moutoussamy Joël
  , 2009. Parmi les principes de la mesure du champ magnétique haute sensibilité, éligibles pour l'investigation des ondes plasmas des environnements terrestre et planétaire, les capteurs à effet de magnétoimpédance géante (GMI) suscitent un intérêt certain, qui dépasse les applications spatiales. Connue comme la variation de l'impédance de micro-fils, de films ou de sandwichs ferromagnétiques provoquée par l'amplitude du champ magnétique, ils sont excités directement par un courant, de fréquence de quelques mégahertz à plusieurs dizaines de mégahertz. La modification de la profondeur de peau à travers la variation de la perméabilité provoque une atténuation géante de l'impédance. Héritant du même principe, les nouvelles solutions de GMI utilisent soit un ruban ferromagnétique sur lequel est enroulé un bobinage de N spires à la manière d'inductances planaires soit deux rubans enserrant un bobinage à la manière de sandwichs bobinés. Le bobinage isolé électriquement, réalise à la fois l'excitation magnétique et la prise de mesure et son comportement inductif permet de transposer dans les très basses fréquences (5kHz- 1MHz) la détection du champ magnétique statique ou lentement variable (F<1kHz). La structure bobinée simplifie le procédé de fabrication et améliore l'excitation magnétique qui peut être dirigée dans les deux directions du plan du ruban ferromagnétique permettant ainsi d'accéder à toutes les composantes du tenseur anisotrope des perméabilités associées aux différentes directions relatives entre l'anisotropie magnétique et le champ magnétique statique tout en bénéficiant du champ démagnétisant le plus favorable. Le début des travaux concerne une étude expérimentale des GMI classiques puis des GMI bobinées utilisant différents matériaux magnétiques tels que les rubans nanocristallins recuit sous champ transverse ou longitudinal, les rubans mumetal ou encore les noyaux ferrite. Cette étude montre également l'influence principale de l'effet de la forme géométrique du ruban ferromagnétique sur la sensibilité intrinsèque et le champ de polarisation. La caractérisation des performances repose sur la mesure de l'impédance et de la sensibilité intrinsèque en lieu et place du MI ratio. Concluant sur le rôle majeur de la perméabilité différentielle, la suite des travaux concerne le calcul du tenseur des perméabilités à partir de l'équation de Landau-Lifshitz-Gilbert couplé à un modèle de perméabilité de décroissance monotone corrélée avec l'expérience. Le modèle proposé repose sur la combinaison d'une perméabilité transversale et longitudinale de rotation de l'aimantation d'une part et d'une perméabilité longitudinale de déplacement de parois magnétiques d'autre part. A partir d'un modèle électromagnétique tenant compte de l'effet de peau et de la parité du champ magnétique inhérente à ces structures bobinées, le concept de GMI bobiné est généralisé aux deux positions possibles du bobinage qui permet d'exploiter en plus des composantes diagonales du tenseur des perméabilités, les perméabilités croisées. Les modèles des impédances et des sensibilités intrinsèques sont comparés aux résultats associés au ruban à anisotropie transversale associé au bobinage transverse puis longitudinal.
• Transport non linéaire dans un réacteur hélicon
  
  • Liard Laurent
  , 2009. Radiofrequencies Plasmas, widely used microelectronics, requires sufficiently low ionization rates so that the diffusion of plasma is governed by charges particles interaction with the neutral gas. Space propulsion requires higher ionization rates (few %), modifying considerably the transport of the species towards the walls. This thesis presents a theoretical and experimental analysis of these strongly ionized plasmas in the presence of an external magnetic field. Several unidimensional fluid models including neutral dynamics in various modes of pressure are studied. Their analysis, primarily analytical, highlights the presence of a neutral depletion at the center of the discharge which involves an increase in the ion flux at the wall. The power balance and the particle balance become coupled. The addition of the neutral energy balance shows that the gas heating is the principal cause of the neutral depletion. Various measurements in the diffusion chamber of an helicon reactor corroborate these theoretical forecasts. The increase in temperature of gas is quantified by LIF on argon metastables. The neutral gas density, measured by TALIF, is minimum in the center of the discharge and also presents a decrease of its mean value, very sensitive to the magnetic field. A temporal study of this phenomenon shows that the minimum of depletion in the center appears in a typical time of diffusion (milliseconds) whereas the mean density, resulting from balance between injection and gas pumping, spends more than one second to be stabilized.
• Sources of energetic backstreaming particles in the electron foreshock: 2D PIC simulation of a curved supercritical shock
  
  • Savoini Philippe
  • Lembège Bertrand
  , 2009. The electron foreshock located upstream of the shock front is populated with electrons having interacted with the shock and then are reflected back with an high energy gain. These backstreaming particles propagate along the interplanetary magnetic field into the solar wind and are associated to an important wave activity. One of the important unresolved problem is the exact origin of these high-energy backstreaming charged particles. It is widely accepted that the shock back-streaming electrons have been accelerated through a fast-Fermi interaction (Type 1) but such oversimplified picture has to be strongly modified when the internal structure and the nonstationarity of the shock front are taken into account. The purpose of the present work is to identify the different sources of backstreaming electrons. This work is based on the use of two dimensional PIC simulation 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. The analyis is restricted within a quasi-perpendidular shock with 90° ≥ ΘBn ≥ 45°, where ΘBn is the angle between the shock normal and the upstream magnetostatic field. These simulations allow to reproduce salient features of a curved supercritical shock both for particles and for electromagnetic fields (Savoini et Lembege, 2001). Electromagnetic precursor emitted by the shock front as ΘBn decreases is observed and parallel electrostatic turbulence is evidenced in conjonction with the reflected electrons. In complement to previous works, present results evidence almost three -instead of two- different classes of electrons which contribute to the backstreaming population, depending on their interaction with the shock front: (i) the mirrored reflected electrons (Fermi type 1) in the shock front, (ii) the resonant population trapped within the parallel electrostatic potential well in the overshoot region and which gains enough energy to escape back into the upstream region and (iii) the leaked electrons which penetrate more deeply into the downstream region and are also locally accelerated before reaching appropriate conditions at the shock front to escape back into the upstream region. The third population includes particles penetrating the shock front around ΘBn=90° but escaping from the shock front at strongly oblique direction (around 50°). This explains why these so called leaked electrons have not been observed in previous simulations (Savoini et Lembege; 2001) restricted to a narrower angular range (90° ≥ ΘBn ≥ 45°). Details on their acceleration mechanisms will be presented and compared with previous works. Reference : Savoini Ph. et B. Lembège, " Two-dimensional simulations of a curved shock: Self-consistent formation of the electron foreshock ", J. Geophys. Res., Vol. 106, pp 12975-12992, 2001.
• Strong electronegative plasmas applied to space propulsion
  
  • Aanesland Ane
  , 2009.
• Progress on the electronegative plasma thruster PEGASES
  
  • Popelier Lara
  • Aanesland Ane
  • Chabert Pascal
  , 2009.
• eGY-Africa: Addressing the digital divide for science in Africa
  
  • Barton C. E.
  • Amory-Mazaudier Christine
  • Barry B.
  • Chukwuma V.
  • Cottrell R.L.
  • Kalim U.
  • Mebrahtu A.
  • Petitdidier Monique
  • Rabiu B.
  • Reeves C.
  Russian Journal of Earth Science, American Geophysical Union, 2009, 11, pp.ES1003. Adoption of information and communication technologies and access to the Internet is expanding in Africa, but be- cause of the rapid growth elsewhere, a Digital Divide be- tween Africa and the rest of the world exists, and the gap is growing. In many sub-Saharan African countries, educa- tion and research sector su er some of the worst de cien- cies in access to the Internet, despite progress in develop- ment of NRENs {National Research and Education (cyber) Networks. By contrast, it is widely acknowledged in policy statements from the African Union, the UN, and others that strength in this very sector provides the key to meeting and sustaining Millennium Development Goals. Developed coun- tries with e ective cyber-capabilities proclaim the bene ts to rich and poor alike arising from the Information Revo- lution. This is but a dream for many scientists in African institutions. As the world of science becomes increasingly Internet-dependent, so they become increasingly isolated. eGY-Africa is a bottom-up initiative by African scientists and their collaborators to try to reduce this Digital Divide by a campaign of advocacy for better institutional facili- ties. Four approaches are being taken. The present status of Internet services, problems, and plans are being mapped via a combination of direct measurement of Internet per- formance (the PingER Project) and a questionnaire-based survey. Information is being gathered on policy statements and initiatives aimed at reducing the Digital Divide, which can be used for arguing the case for better Internet facil- ities. Groups of concerned scientists are being formed at the national, regional levels in Africa, building on existing networks as much as possible. Opinion in the international science community is being mobilized. Finally, and perhaps most important of all, eGY-Africa is seeking to engage with the many other programs, initiatives, and bodies that share the goal of reducing the Digital Divide either as a direct policy objective, or indirectly as a means to an end, such as the development of an indigenous capability in science and technology for national development. The expectation is that informed opinion from the scienti c community at the institutional, national, and international levels can be used to in uence the decision makers and donors who are in a position to deliver better Internet capabilities. (10.2205/2009ES000377)
  DOI : 10.2205/2009ES000377
• SMALL-SCALE ELECTRON DENSITY FLUCTUATIONS IN THE HALL THRUSTER, INVESTIGATED BY COLLECTIVE LIGHT SCATTERING
  
  • Tsikata Sedina
  , 2009. Anomalous electron transport across magnetic field lines in the Hall thruster plasma is believed to be due in part to plasma oscillations. Oscillations of frequencies on the order of a few megahertz and of wavelengths on the order of a millimeter have been shown to be likely to lead to transport. Measurements of fluctuations at these length scales is, however, beyond the reach of conventional thruster diagnostics such as probes. This work describes the first application of a specially-designed collective light scattering diagnostic (PRAXIS) to the measurement of electron density fluctuations and the subsequent identification of unstable modes in the thruster plasma. Two main high frequency modes are identified, propagating azimuthally and axially, of millimetric length scales and megahertz frequencies. The propagation directions and angular openings of the modes are determined. The azimuthallypropagating mode, believed to be responsible for transport, is shown to have wave vector components antiparallel to the magnetic field and parallel to the electric field, and to propagate within an extremely limited region. The axially-propagating mode is shown to have features closely related to the ion beam velocity and divergence. The electron density fluctuation level is calculated and is associated with a high electric field amplitude. The experiments, confirming a number of predictions arising from linear kinetic theory, also provide much additional information permitting the improvement and development of models for both modes.
• Absorption spectroscopy diagnostics of a dual-frequency capacitive dielectric etch tool using Ultraviolet Light-Emitting Diodes
  
  • Booth Jean-Paul
  • Bredin Jérôme
  , 2009.
• Benefits of an extended low shear region for the confinement of tokamak plasmas
  
  • Firpo Marie-Christine
  , 2009.
• Impact of load geometry on plasma formation and radiative properties of Z-pinches at stagnation
  
  • Kantsyrev Viktor L.
  • Safronova Alla S.
  • Esaulov A. A.
  • Velikovich A. L.
  • Rudakov Leonid I.
  • Chuvatin Alexandre S.
  • Williamson Kenneth M.
  • Yilmaz M. F.
  • Obsorne G. C.
  • Weller Michael E.
  • Shrestha Ishor
  • Shlyaptseva V. V.
  , 2009, 54 (15), pp.GO5.00013.
• Evidence of production/losses of NO on a pyrex surface under and after plasma exposure
  
  • Marinov Daniil
  • Guaitella Olivier
  • Ionikh Y.
  • Rousseau Antoine
  , 2009.
• Absorption spectroscopy diagnostics of a dual-frequency capacitive dielectric etch tool using Ultraviolet Light-Emitting Diodes
  
  • Bredin Jérôme
  • Booth Jean-Paul
  , 2009.
• Dual-frequency capacitive radiofrequency discharges : Effect of low-frequency power on electron density and flux
  
  • Booth Jean-Paul
  • Curley G.
  • Chabert Pascal
  • Maric D.
  , 2009.
• Structure of a MHCD in the normal regime at medium pressure range in pure argon
  
  • Lazzaroni Claudia
  • Chabert Pascal
  • Rousseau Antoine
  • Sadeghi N.
  , 2009.